GreenShoot by Infomedia18

INTRODUCTION 2

What is UNIDO? Over the last four decades, UNIDO—a specialised agency of the UN—has been promoting industrial progress in the developing world. UNIDO’s objectives are two-fold: as a global forum, UNIDO generates and disseminates industry-related knowledge and as a technical cooperation agency, it provides technical support and implements projects. Some of the challenges addressed by UNIDO include reduction of poverty through productive activities, promoting the integration of developing countries in global trade through trade capacity building, fostering environmental sustainability in industry and improving access to energy. It is of grave concern that global industrial production and consumption are outpacing the renewal capacity of natural resources and the capacity of governments to manage pollution and wastes. While on one hand, industrial growth has helped draw out tens of millions of people from the shackles of poverty in many countries over the last few decades; on the other hand, this economic growth and urbanisation have come at a price. Urbanisation, particularly in many developing countries, is accompanied by inadequate or non-existent environmental and urban services, including recycling systems, wastewater treatment and sewage systems, drainage, water supply, sanitation and solid waste management. This results in stresses on natural resources apart from endangering public health and causing climate changes. On the whole, such kind of haphazard urbanisation constraints the long-term growth of urban centres. Providing access to modern and reliable energy supplies is considered a prerequisite for economic development in developing countries. For such development to be sustainable, this energy must be used to promote productive uses that create jobs and more income-generation opportunities for local communities. UNIDO, therefore, helps countries increase access to modern energy supplies, especially based on renewable energy, in order to support the development of productive capacities in both rural and urban areas. The growing gap between energy supply and demand has resulted in renewable energy assuming a critical role in meeting the rising demand for energy, especially by industries in developing countries. Several renewable energy technologies have emerged as economically viable and environmentally friendly options, which if suitably adopted, can meet growing energy needs of the industry, particularly, of Small and Medium-sized Enterprises (SMEs). UNIDO promotes industrial applications of renewable energy in energy-intensive manufacturing SMEs. Currently, SMEs satisfy a significant majority of these requirements through electricity derived from fossil fuels or from the direct combustion of such fuels, in the form of furnace oil, kerosene or coal. In view of the rapidly rising cost of these fuels, enhanced use of renewable energy technologies would not only improve the local environment but also increase the productivity and competitiveness of SMEs. It also offsets unreliable energy supplies from national grids. UNIDO advises national and regional planners and decision makers in elaborating strategies for their industrial energy mix, considering all available technologies, with a focus on renewable sources of energy. Further, UNIDO promotes national and regional production as well as renewable energy technologies and adequate support structures, including innovative financial schemes.

UNIDO ICAMT - Background In order to encourage SMEs in South Asia, the UNIDO ICAMT (International Center for Advancement of Manufacturing Technology) has been established in India. Apart from the industry in India, UNIDO ICAMT also caters to the needs of SMEs in Afghanistan, Bangladesh, Bhutan, Maldives, Nepal and Sri Lanka. UNIDO ICAMT’s main objectives include helping the industry, particularly SMEs, and enhancing productivity of the manufacturing industry and its competitiveness through promotion, transfer, commercialisation and diffusion of advances & innovation in manufacturing technologies. UNIDO ICAMT provides a wide range of services— these include project engineering, training courses, demonstrations and assistance in

selecting, assessing, negotiating and transfer of new technologies & innovations in consideration of the needs of partner countries and their economic contexts. Since its inception, UNIDO ICAMT has been instrumental in assisting a number of industries in technology transfer, upgradation and modernisation, skill development as well as policy and strategy formulation & implementation. UNIDO ICAMT partnerships with government and private organisations in South Asia are integrated with national research and production cooperation programmes. In fact, over the years, UNIDO ICAMT, through its programmes, has reached out to regions of Africa, Asia and Latin America and has successfully promoted low-cost housing using local investments and materials gathered from local resources. A similar initiative undertaken in India helped populations in Madhya Pradesh and Bihar implement similar housing principles. ICAMT has, in the past, established National Programs for the Development of the Indian Stone, Toy and Lock industries. More recently, UNIDO ICAMT has been working with the machine tool, plastics and foundry industries in India. Through the focused cluster initiative, ICAMT’s National Experts have helped numerous Micro, Small and Medium Enterprises (MSMEs) integrate best practices and implement the latest manufacturing technologies. Perspective plans that focus on capacity building, technology upgradation and marketing have resulted in companies increasing their revenue and exports in short periods of time.

UNIDO ICAMT’s initiative towards Sustainable Development – A ‘Green’ Compendium As a step towards promoting sustainable development amongst MSMEs in the machine tool, plastics and foundry sectors, UNIDO ICAMT has undertaken the research and compilation of a compendium of environmentally friendly or ‘green’ manufacturing technologies. With rapidly depleting resources, it becomes essential for industry leaders to move towards energy-efficient and cleaner methods of manufacturing. In this context, the following compendium titled Green Shoots, comprising environmentally friendly manufacturing technologies, has been developed. The main motivation towards creating such a database is to facilitate information and technology exchange between companies. The accompanying case studies with each of the discussed ‘green’ technologies ensure that companies realise that these measures are indeed implementable. A minimum of a dozen environmentally friendly manufacturing technologies have been discussed under each of the three sections of the compendium. It should be noted that a technology is ‘green’ if it satisfies at least one of the following parameters: 1. Energy reduction/use of alternate means 2. Minimisation of hazardous materials and use of eco-friendly materials 3. Minimisation of emissions and noise 4. Waste treatment and disposal technology 5. Mechanical and chemical recycling This compendium aims to not only glean the extent of ‘greenness’ but also highlight the present technological and human resource gaps that may hinder ‘green’ technology implementation in the coming years.

Remarks The information contained in this compendium was compiled through use of library resources such as research papers and scientific journals, textbooks, the internet, interactions with industry personnel and also individuals from educational and research institutions. Costs, particularly in the case of MSMEs, have been and will always be a driving factor, but one of the most poignant aspects of this compendium is the realisation that small changes can bring about significant monetary improvements. As legislation pertaining to promoting the environment gradually takes effect, especially in developing nations, companies and manufacturing units must incorporate newer practices and evolve to transform themselves into ‘green’ establishments. It is hoped that the content of this compendium will help educate and provide exposure to the industry. It is also hoped that this ‘green’ compendium will find applications not just within the machine tool, plastics and foundry industries, but will also inspire and motivate other industrial sectors.

2 Introduction 7 Foreword

Dr Kandeh K Yumkella Director General - UNIDO

9 Foreword

Shrinivas G Shirgurkar Managing Director, Ace Designers Limited

11 Foreword

Vikram Kirloskar Vice Chairman, Toyota Kirloskar Motor Pvt Ltd and Chairman, Global Innovation & Technology Alliance Limited

13 Preface

Manas Bastia Senior Editor, Network 18 Publishing Archana Tiwari-Nayudu Editor, Network 18 Publishing

16 Introduction

Indian Machine Tool Sector

17 Foreword

Shailesh Seth Corporate Strategy Advisor & Senior National Consultant - UNIDO

CONTENTS

Machine Tool

18 Machine weight reduction

Lightweight components in the makingâ&#x20AC;Ś

20 22

Minimum quantity lubrication Innovation & efficiency in every drop Dry machining Green machining at its best

Cutting fluids Healthy manufacturing at its best!

Chip compacting Reuse, recycle, regain

28 Pro-active maintenance A world of difference!

30 32

Sound enclosures Shhhhh...! Manufacturing in progress Inverter and servo controlled motors Solution for energy conservation

Plastics

34 Rapid prototyping

48 Injection moulding machine

36 Friction stir welding

50 Injection stretch blow moulding

38 Hydrocarbon cleaning

52 Hot runners in injection moulds

40 Energy savings through Kaizen

54 Upcoming injection moulding

Matched to perfection! Connecting the dots of growth Cleaning it green!

Change for the better!

In an energy-efficient avatar Going light

Channelising savings

technologies Co-existing at its best

56 Solar rotational moulding Casting in the sun

42 Facts & Figures

58 Wood plastic composites

46 Introduction

60 Zero liquid discharge technology

47 Foreword

62 Sugarcane-derived plastics

Indian machine tool sector Indian plastics sector Vijay Merchant President, Indian Plastics Institute

Working together as one! Creating ripples

Sweet source of packaging material

64 Recycling polystyrene

Producing eco-friendly blocks

66 Waste plastics in cement concrete Leading the way

68 Delamination of laminated packaging A cleaner disposal process

Foundry

70 Waste plastics in cement kilns

88 Role of optimised cupola design

Waste plastics in railway sleepers A silent journey

Zero pellet loss Clean sweep!

Use of heat exchanger in cupolas Bartering heat for heat

Duplexing Refurbishing & recarburising the cupola

MF & dual track induction furnace and IGBT technology Increasing melt efficiency

Energy conservation in cooling towers Lightweight cooling

Fuelling an energy-intensive industry

76 Constraint-based planning and

scheduling Energy consumption optimisation

Use of rapid prototypes Developing component plastics

80 Facts & Figures

Indian plastics sector

Introduction Indian foundry sector

Foreword Pradeep Bhargava Director, Cummins India Ltd.

87 Foreword

Harsh K Jha President, Indian Institute of Foundrymen - Kolkata

Better design, better energy Savings

98 Use of VFDs in cooling towers Cooling by drives

100 Environmentally-friendly resins Nature responsive resins

102 Variable frequency drives Adding energy efficiency to screw compressors

104 Simulation casting software

From idea to eco-friendly reality

106 Automatic fettling

Trimming the automatic way

108 Recycling spent foundry sand Building a sustainable future

110 Precision granite

Using alternative materials for long lasting castings

112 Planetary gears in intensive mixers Energy optimisation during sand casting

114 Drying in foundries

Radio signals to the rescue!

116 Facts & Figures

Indian foundry sector

119 Conclusion

Marching towards green

120 Reference 124 Index

Dr Kandeh K Yumkella Director General - UNIDO

It gives me great pleasure in introducing this compendium developed by UNIDO-ICAMT on environmentally friendly manufacturing technologies. Environmentally friendly technologies protect the environment, are less polluting, use all resources in a more sustainable manner, recycle more of their wastes and products and handle residual wastes in a more acceptable manner than the technologies for which they were substitutes. The following compendium is a compilation of manufacturing methods with a focus on three industry sectors- the Indian machine tools industry, the Indian plastics industry and the Indian foundry industry. A minimum of a dozen environmentally friendly manufacturing technologies have been discussed under each of these three sections of the compendium. The study conducted by UNIDOICAMT not only helps the audience determine the extent of ‘greenness’, but also highlights the present technological and human resource gaps that may hinder ‘green’ technology implementation in the coming years. The case studies provided help readers realize that by the implementation of a few new technological practices, organizations can not only go ‘green’ but can also benefit from huge cost savings over time. I would like to state that the information contained in this compendium is extremely relevant – from large corporations to small and medium scale enterprises, and also amongst both, developing and developed nations. To conclude, I would like to congratulate UNIDO-ICAMT for undertaking this initiative towards promoting sustainability in industry through the research and compilation of this compendium on environmentally friendly manufacturing technologies.

Shrinivas G Shirgurkar Managing Director, Ace Designers Limited

It gives me great pleasure in introducing the UNIDOICAMT compendium on ‘Environment friendly’ manufacturing technologies. I believe the UNIDOICAMT document to be an initiative in promoting green, clean, lean and sustainable production amongst the Indian industries, particularly the Small Scale Industry. This compendium focuses on manufacturing technologies in the machine tools, plastics and foundries sectors – Three major sectors impacting Indian economy. The establishment of research and development within Indian companies, with an emphasis on adapting, developing and practicing ‘green’ processes which enables industries to align with the national initiative on manufacturing policies and also keeping pace with the global trends on environment. Green manufacturing is mandatory for industries in the near future and all the industries, especially export oriented industries should implement green practices in manufacturing. Although the technologies discussed and the case studies presented in this compendium are related to the machine tools, plastics and foundry sectors, I believe this document to be relevant to all Indian industry. A document such as this will help raise awareness about the green initiatives in manufacturing. The case studies presented in the document enable industries to adapt and implement number of different methods towards greener practices. To conclude, I would like to congratulate UNIDOICAMT on producing this well-researched and well-presented technical document that will enable small-scale industry reach their true technological potentials.

Vikram Kirloskar Vice Chairman, Toyota Kirloskar Motor Pvt Ltd and Chairman, Global Innovation & Technology Alliance

One of UNIDOâ&#x20AC;&#x2122;s most unique and challenging mandates is supporting sustainable industrial development. Sustainable industrial development encompasses technology transfer, strengthening small-scale units and investment and environmental management within industry i.e. cleaner production and safer work places. With energy and raw material becoming scarce and thereby expensive, it is important for industry to recognize the importance of viable solutions very quickly. In this context, the given compendium aims to address environmentally sustainable manufacturing in the Indian machine tools, plastics and foundries sectors with more than 40 â&#x20AC;&#x2DC;greenâ&#x20AC;&#x2122; manufacturing technologies that have been discussed. What is important to note is that case studies at relevant junctures of the document illustrate the overall benefit companies have availed not only by implementing the technology in question but also through an efficient management of the green technologies. Moreover benefits have been illustrated in terms of mitigating raw material wastage, optimizing energy consumption, minimizing harmful emissions along with the realization of benefits in terms of quantifiable cost reduction for the company. The compendium highlights the fact that the implementation of a few technological changes and adoption of a handful of industrial best practices can result in monumental savings, whilst also reducing the negative impact on the environment. As representatives of the Indian Manufacturing Industry we would like to thank UNIDO ICAMT for this wonderful initiative to better serve the industry and its need for sustainability in the near future.

Preface

An Eco-friendly Edge Manas R Bastia Senior Editor, Network 18 Publishing

The entire gamut of manufacturing seems to be turning a new leaf—green manufacturing. This manufacturing concept involves using green energy and processes in operations as well as in developing green products. With rising concerns on climate change, depleting natural resources, increasing pollution, escalating energy & input costs and growing regulatory pressures with stricter environmental laws, practicing green principles is now an integral part of business and even perceived as conducting good business. Adopting green practices can be as varied as planning for green as a core part of business strategy, executing green initiatives across the value chain by moving towards green energy & processes and promoting green initiatives as part of corporate social responsibility. In the plastics sector, for example, importance is now being laid upon building large capacities for the production of bio-based versions of bulk plastics such as polyethylene and polyethylene terephthalate. Companies that adopt green practices benefit through long-term cost savings, brand enhancement, greater ability to attract talent and higher investor interest. UNIDO, in association with Network 18 Publishing, presents this compilation of the latest green initiatives to help you get closer to several green practices, technologies and products that have a lower impact on the environment. Read on to get more eco-friendly, energy-saving and economical solutions to gain a global business edge.

An Anthem for Ourselves Sprouts, statements, stance & substance for greening the manufacturing ecosystem is all about reconciling economic development with protection of the environment. It represents a very promising approach. Eco- or environmentfriendly manufacturing protects the planet from exploitation and conserves natural resources. Products are made from sustainable materials, while waste is reduced through re-manufacturing, reusing and recycling or by using rapidly renewable materials. Besides being a friend of the earth, being eco-friendly can reduce business costs as well. This is where Business Sense Meets Best Intentions!

Archana Tiwari-Nayudu Editor, Network 18 Publishing

As we expect the industry to ‘turn a new leaf’, we present to you this extensive research-based content, which is presented in the most easy-to-consume way with high aesthetic design and picture support. Sprinkled with interesting stats, facts, history, trivia & anecdotes, the uniqueness of this compendium lies in the compilation of techniques, technologies and case studies of green practices that manufacturers in the machine tool, plastics and foundry sectors have innovated, evolved, indigenised and imbibed. We know that this clogged world needs fresh thoughts, these bogged-down brains need stimulating ideas, the human race needs nature and nature needs you … to protect, preserve & profit from it … yes, we are using the word ‘profit’ in a green book. This is the beginning of the differentiating edge of this initiative— an anthem called Green Shoots! As we splash Green on the Grey canvas, we pose a ponderous question for you to answer: Are you letting ‘Green’ limit you or Liberate you?

Indian Machine Tools Sector

he Indian Machine Tools Manufacturersâ&#x20AC;&#x2122; Association (IMTMA) has, as per the latest available data, placed India at the 12th position in terms of production and at the 7th position in terms of consumption of machine tools. India, as has been predicted, is set to become a key player in the global machine tool industry and is likely to witness substantial high-end machine tool manufacturing. Industry experts say that this phenomenon is linked to the spurt in manufacturing, for which the machine tool sector serves as the mother industry. Since manufacturing capacity is stagnating and the growth rate for the machine tool industry is falling in developed economies, shifting the machine tool capacity to low-cost, high-skill geographies like India has become imperative. For the Indian machine tool sector, this would mean steadily working on ensuring that the industry develops the infrastructure and technical expertise to take advantage of this scenario. To achieve this, it is important to recognise that although the Indian machine tool industry has come a long way since independence, it now needs to be further strengthened in order to cost-effectively produce quality machine tools through technological upgrade and market development. The Indian industry has an abundance of skilled manpower, basic raw materials and a rising class of technical entrepreneurs. It should be noted that the performance of Indian machine tool enterprises can be greatly improved by addressing productivity, quality, reliability and service. Apart from this new technology upgrade through research and development, in particular, technologies addressing the concepts of increased sustainability and â&#x20AC;&#x2DC;greeningâ&#x20AC;&#x2122; the industry will play a vital role in increasing the competitiveness of Indian machine tool makers. This section of the compendium describes sustainable manufacturing technologies that are currently practiced in the industry not only abroad but also in India. This is the first step in educating and exposing companies, in particular, MSMEs, to the importance of sustainable technologies not only from the environmental point of view but also from the viewpoint of long-term economic benefits.

Indian

Machine Tool Sector 16

Shailesh Seth Corporate Strategy Advisor & Senior National Consultant - UNIDO

Alternate Business Models, Looking Ahead Historically, machine tool companies that started in 1960–70s imbibed full vertical integration because back then, the industry was small, volumes were small. This did not permit an economically viable outsourcing-based business model. It was almost forced by circumstances. In the late 70s, because of high investment costs, manufacturers were forced to develop a vendor base wherever it did not exist. Slowly, this culture developed and spread. It allowed companies that started in the late 70s–early 80s to opt for the outsourcing-based business model. There was also another pressure point. New entrepreneurs lacked financial resources and were therefore obliged to work hard to create and strengthen the supply chain. Finally came the champion of outsourcing— the automotive industry—and the impetus to outsourcing started in the right earnest. It became the new mantra.

E P

Globally, business models are directly linked to volumes. Up to a certain volume, an outsourcingbased business model is the most suitable. Beyond that, when economies of scale have to begin to operate, some vertical integration becomes necessary. Therefore, companies should practice a judicious mix of vertical integration and outsourcing with a clearly defined strategy for ‘make vs. buy’. This strategy should also encompass how to develop new vendors, improve current vendors and create a partnership-based commercial relationship that can bring sustainable benefits to both. It is also essential to ensure that the vendors chosen have the capacity to grow with your company’s growth plans and that they do not become a bottleneck in your path.

Y T O T O T R X P E T

As the technology progresses to arenas like multi-axis, multi-tasking machining and high-speed machining, it will require specialised knowledge and experience in the design and manufacture of sub-elements of such machines. It would be too complex a task for a company to employ high cost people with such diverse specialisations. Thus, the future will drive more companies towards lower levels of vertical integration and higher levels of outsourcing. For machine tool manufacturers, it is essential to control functions such as design, assembly, quality assurance, customisation and do small amounts of critical manufacturing in-house. This concept requires a different managerial philosophy—where the management of logistics will outweigh the management of manufacturing processes. A large number of Indian machine tool companies are at this threshold level, where they will have to make decisions about the business model they want to follow. This is a very serious decision and once a path has been chosen, it will be very difficult, if not impossible, to alter it. The Indian machine tool industry has to define its path to destiny ... NOW.

Machine weight reduction

Lightweight

COMPONENTS in the Making…

Accuracy, Reliability, Cost-efficiency … qualities like these define a machine for what it is. In the quest to increase the value of machines while staying true to the environment, several threads are bound together to make machines more efficient and green. One such thread is the optimisation of power consumption through the weight reduction of dynamic machine elements, such as structures under movement, without compromising on stiffness and functionality. However, successful reduction in machine weight depends on the development of new materials and their subsequent deployment in machines, for instance, lightweight structural designs.

he power efficiency of machine tools can be improved by using high-efficiency motors, low-friction feed drive system, high-efficiency cooling systems and techniques of low power consumption during machine idling. The weight reduction of machines can also prove fruitful in reducing consumption. This brings us to think: How does weight reduction actually materialise? A machine’s weight can be substantially reduced by replacing certain parts originally manufactured in metal by those manufactured out of lightweight metals such as composite materials-based metal matrix composites.

HERE’S WHY YOU NEED LIGHTWEIGHT MACHINES Modern machine tools have to meet requirements such as precision, productivity and reliability. Due to the constantly increasing demand, extremely stiff mechanical systems are implemented with the capability to absorb arising inertia forces. As a consequence, the mass of machine structures, such as moving machine components, has to be increased. Here, the majority of the mass serves dynamical stiffness, whereas a fractional part performs the kinematic tasks. The high amount of mass, in turn, requires motors with high torque output, which increase the force needed during acceleration and deceleration. This results in high energy consumption and increase in costs.

A clamping device made of carbon fibre instead of steel is as much as 66% lighter, stronger and even more rigid—with identical clamping force values.

The power used during the cutting process forms only 25% of the total power consumed by the machine’s typical system costs.

UNPLUGGING MACHINE WEIGHT REDUCTION In order to reduce the machine mass and realise energy savings, two strategies can be pursued at the same time: g

Replacement of Currently Implemented Materials with Lightweight Alternatives

An overview of different lightweight materials illustrates that not only material characteristics but also specific costs and technical mastery are of high relevance when choosing a potential material. Therefore, it can be expected that titanium and Carbon Fiber Reinforced Carbon (CFC) materials are applied only to special machine tool parts for highly specific applications, as are hybrid structures. The use of epoxy resins, polymer cement, mineral bed castings, etc. is highly recommended. The more the technological mastery, the higher will be the use of hybrid structures of aluminium, polymer cement, steel and technical ceramics for lightweight constructions.

Structure Optimisation of Machine Components to Allow Material Reduction

Structure optimisation reduces the weight of moving parts and minimises energy consumption and costs. The crucial factors for evaluating structure quality are mass; static stiffness (tool deviation from the predefined path caused by applied forces); natural frequencies (definition of the dynamic behaviour in the closed control loop) and deflection (dead weight during acceleration). Setting these factors into relation, a measure for realising a mass with the required characteristics can be obtained. Traditionally, the design engineer carries out structure optimisation using his/her practical knowledge. In the past, several methods for automated topology optimisation were developed and applied. Using Finite Element Method (FEM) calculations, iterative adjustments of the initial structure to the reduced amount of materials were also realised. Here, the result of the adjustments does not influence the mechanical characteristics of the materials. Mass reduction, i.e. mass optimisation, in principle, is possible for all machine tools. Besides the potentially additional design efforts, there are no additional costs of implementing this option. On the contrary, material savings are directly related to cost and energy savings.

REALISING THE POTENTIAL… National Chung Cheng University (CCU) in Taiwan has developed: l Lightweight structural design based on topology optimisation l Lightweight material made of magnesium matrix composites l Dynamic analysis of parallel kinematic machines

…AND BENEFITTING FROM IT l Bharat Fritz Werner (BFW) India has—through the development of the VMC-Agni machine— implemented the electrical power saving concept of lightweighting. By using the FEM analysis, it optimised the structure of the machine components and thereby reduced material weight. l Trumpf Sachsen GmbH, in cooperation with Fraunhofer IWU, developed a crossbar of a laser cutting machine using a carbon fibre reinforced material. This CFC material is superior to metallic materials in many ways (e.g. stiffness, stability, damping, fatigue strength, thermal expansion). This led to not only a mass reduction of 50% but also a twofold increase in the component stiffness.

Say Yes to Machine Weight Reduction! Remarkable energy saving

Reduction in machine footprint

Conclusion Reducing the size and weight of parts is a good way to improve fuel economy and save resources. Replacement of materials with lightweight alternatives has proven to be one of the best ways to reduce the energy consumption. This process can save high amount of energy and prove fruitful with respect to business as well as environment.

Minimum quantity lubrication

Innovation & Efficiency in Every

The risks involved in machining with coolants have been emphasised for a while now. Coolants are said to be harmful to humans, cause pollution and have a very high maintenance cost. Tackling this problem at the forefront is Minimum Quantity Lubricationâ&#x20AC;&#x201D;a new machining method that delivers the minimum required quantity of lubricant mixed with air and performs machining through a continuous supply of an oil/air mixture to the cutting edges.

inimum Quantity Lubrication is a method that makes it possible to reduce the amount of coolant used. With growing concerns over the negative effects of cutting fluids on people and the

environment as well as high maintenance costs, reduction in the usage of coolants is highly essential. In conventional mass-production systems such as in the automotive industry, a large volume of cutting fluids is used to improve productivity and machining accuracy.

Unplugging Minimum quantity lubrication Minimum Quantity Lubrication refers to the use of cutting fluidsâ&#x20AC;&#x201D;typically with a flow rate of 5 ml/ minâ&#x20AC;&#x201D;rather than the amount commonly used in flood cooling condition, where, for example, up to 5 litres of fluid can be dispensed per minute. The lubricant will be atomised so finely by a precise dosing technology that there will be no visible spray. The resultant thin lubricating film remains there even under high pressure and reduces the friction energy during the machining process.

Types of Minimum quantity lubrication Technological differentiation: In volumetric metering systems, both lubricant and air are supplied to a spray nozzle or mixing point via coaxial feed lines. The lubricant is then atomised using compressed air and applied to the work zone. In a continually dispensing system, oil mist is generated in the supply unit. A feed line supplies the aerosol to the work zone. Application-orientated differentiation: With external Minimum Quantity Lubrication, the aerosol is supplied to the lubrication point from the outside through nozzles. Using internal Minimum Quantity Lubrication, the tool applies the aerosol directly to the lubrication point.

The use of Minimum Quantity Lubrication leads to a 13% decrease in the overall cost as well as a better cutting tool life.

The Green Quotient The concept of Minimum Quantity Lubrication, sometimes referred to as ‘near dry lubrication’ or ‘micro lubrication’, had been suggested a decade ago as a means to address the issues of environmental intrusiveness and occupational hazards associated with airborne cutting fluid particles on factory shop floors. The minimisation of cutting fluids also leads to economical benefits by way of saving lubricant costs and workpiece/tool/machine cleaning cycle time. This technique combines the advantages of dry processing with those of flood lubrication. In addition, the necessity of cleaning machines and workpieces, and disposal is reduced.

Implementing the Technology The Central Manufacturing Technology Institute (CMTI), along with the University of Kansas, US, introduced Minimum Quantity Lubrication with nano particles to improve surface finish. This reduced coolant use from litres per minute (LPM) to millilitres per hour (MPH). An investigation of Minimum Quantity Lubrication grinding was carried out with the scope of documenting the process efficiency of oil-based nanolubricants. The nanolubricants were composed of MoS2 nanoparticles (<100 nm) dispersed in two different base oils—mineral oil (paraffin) and vegetable oil (soybean). Surface grinding tests were carried out on cast iron and EN 24 steel under different lubrication conditions— Minimum Quantity Lubrication using nanolubricants (varying compositional chemistry and concentration of nanoparticles), pure base oils (without nanoparticles) and base oils containing MoS2 microparticles (3–5 μm) and flood grinding using water-based coolants. Specific energy, friction coefficient in grinding and G-ratio were used as measurands for determining the process efficiency. The results indicated that Minimum Quantity Lubrication grinding with nanolubricants increased the process efficiency by reducing energy consumption and frictional losses at the wheel-workpiece interface. The process efficiency was also found to increase with increasing nanoparticle concentration. Soybean-based nanolubricants and paraffin-based nanolubricants performed best for steel and cast iron, respectively, showing a possible functional relationship between the compositional chemistry of nanolubricants and the workpiece material, which will be the focus in future.

Say Yes to Minimum Quantity Lubrication! þ Less maintenance þ Increases safety by reducing harmful vapour þ Environment-friendly þ Includes the advantages of dry process

Conclusion

Minimum Quantity Lubrication is an environmentally viable technology that helps in reducing manufacturing costs. It is the process of applying a small amount of quality lubricant directly into the cutting tool workpiece interface and is effective in a wide variety of metal cutting processes.

Dry machining

Dry machining implies a moratorium on the use of cutting fluids and chemicals in the machining process. However, to pursue dry machining, one has to compensate for the several beneficial effects of cutting fluids without actually using them. It may even be necessary for the industry to lower its expectations by cutting back on speed or removal rates (if the tool materials canâ&#x20AC;&#x2122;t withstand the stringent conditions of dry machining) when forced to limit or avoid the use of cutting fluids.

n the last 20 years, metalworking fluids have undergone intense regulatory scrutiny. The United Auto Workers petitioned the Occupational Safety and Health Administration (OSHA) to lower the permissible exposure limit for metalworking fluids from 5.0 mg/m3 to 0.5 mg/m3. In response, OSHA established the Metalworking Fluid Standards Advisory Committee (MWFSAC) in 1997 to develop standards

Green Machining

or guidelines related to metalworking fluids. In light of stricter environmental regulations and their enforcement, it will be long before cutting fluids can be considered totally harmless and acceptable. Consequently, elimination of the use of cutting fluids, if possible, can be a significant economic incentive. Also, considering the high cost associated with the use of cutting fluids, the choice seems obviousâ&#x20AC;&#x201D;Dry Machining.

at Its BEST

MWFSAC, in its final report in 1999, recommended that the exposure limit be 0.5 mg/m3, and made medical surveillance, exposure monitoring, system management, workplace monitoring and employee training mandatory in order to monitor workers’ exposure to metalworking fluids.

The costs associated with the use of cutting fluids are estimated to be several billion dollars every year.

Studies on drilling have shown that reducing the edge hone to create a sharper drill can reduce the cutting temperature by 40%.

Unplugging Dry Machining In dry machining, one of the approaches is to improve the properties of tool material by making them more refractory, or generate less heat during machining. Constant development of tool materials over the century has led to the advent of highspeed steels, cast cobalt alloys, ceramics, coated carbides, cubic boron nitride, diamond, etc. However, the increasing need to machine difficult-to-machine materials at increasingly higher cutting speeds warrants the development of new tool materials. Tool material manufacturers are accepting this challenge as the rewards can be considerable. In view of this, monolithic tool materials are being replaced by engineered coated tools. One factor affecting the choice of dry machining is the workpiece. Sometimes, a cutting fluid can stain the part or contaminate it. The workpiece’s suitability for a dry process also depends on the material. For instance, low-carbon steel becomes more adhesive as the carbon content falls. Another factor affecting dry machining are the tool parameters. Because the tools designed for dry machining can be sharper than their counterparts for wet machining, they actually generate less friction and help to control heat. Thus, getting good results in dry machining requires more than specifying the correct cutting tools. It is also important to run them at optimum spindle speeds, feed rates and depths of cut.

The Green Quotient The concept of dry machining has been considered as a means to address the issues of environmental and occupational hazards associated with airborne cutting fluid particles on factory shop floors. The minimisation of cutting fluid also leads to economical benefits by way of saving lubricant costs and workpiece/tool/machine cleaning cycle time. The necessity of cleaning, and disposal problems in machines & workpieces are reduced. In addition, workplace exposure to harmful vapour or skin contact with cooling liquids is also considerably reduced.

Implementing the Technology  Oklahoma State University is working with Technology Assessment and Transfer Inc. in Annapolis, MD, on novel multiplelayer nano coatings (literally several hundreds) on cemented tungsten carbide (in contrast with a few layers of micron sized coatings) suitable for dry machining.  Kennametal - Kennametal Inc. (NYSE: KMT), a leading global supplier of tooling, engineered components and advanced materials consumed in production processes, manufactures inserts that are suitable for dry machining.

Say Yes to Dry Machining! Saves lubricant cost Reduces maintenance Less exposure to harmful vapour

þ þ þ

Conclusion Dry machining has definitely opened up many opportunities to save money and reduce machining time, not to forget its environment-friendliness. Is dry machining the future? If you’re machining hard materials, it could be well worth your time and money.

Cutting fluids

Healthy

MANUFACTURING

at its Best!

In any machining process, there are four important elements: the machine itself, cutting tools, materials being machined and the coolant. Considering the constant improvements and upgrades in manufacturing processes today, it has become extremely important to constantly add and deliver value. For instance, the coolant being used, along with the cutting tools, to convert raw material into finish products can give leverage in reducing frictional forces during machining depending upon the design formulation & additivation. It can also work upon aspects such as tool life and productivity improvement.

uring machining operations, machine shops and manufacturers use and dispose of a significant amount of cutting and grinding fluid. The fluid is used as a coolant and lubricant in cutting operations as well as a vehicle to carry away chips and fines produced in machining and cutting operations. There are several types of cutting and grinding fluids in market,

including both water soluble and non-soluble petroleum-based oils. When these fluids lose their efficiency, they are generally disposed of, and the methods used for disposal are often environmentally unsound. Here, the technique of Cutting Fluid without Bactericide comes into play, as it helps make the process as healthy and green as possible.

UNPLUGGING CUTTING FLUID WITHOUT BACTERICIDE In the technique of using cutting fluid without bactericide, emulsions or cutting fluids need no tankside addition of bactericides. Water-miscible emulsions stay biologically stable inherently, without any bactericides. These emulsions have a highly special way of maintaining the long-term bio-stability of metalworking fluid emulsions. It uses the age-old law of nature whereby bacteria normally colonise aqueous media immediately. To keep the emulsions stable, this is deliberately fostered by creating ideal conditions for harmless environmental bacteria. These bacteria, also present in drinking water, build up a naturally stable biotope where undesirable bacteria have no chance of propagating. We call them primary bacteria because they dominate and are the first to colonise the emulsion.

Both water soluble and non-soluble petroleum-based fluids eventually lose their efficiency and have to be disposed of, and the disposal methods used are often environmentally unsound.

THE GREEN QUOTIENT

IMPLEMENTING THE TECHNOLOGY

The most important benefit for users of this technique is outstandingly good human and environmental compatibility. Since there are no undesirable bacteria, no tankside addition of bactericides is required. The cutting fluid avoids skin reactions or irritations of the respiratory tract resulting from overdosing with bactericide. Uncontrolled growth of unknown bacteria in conventionally formulated metalworking fluid emulsions generally shortens their service life. Such bacteria can reduce the pH value and cause bad odour or even corrosion. Fungal filaments can lead to filter clogging as well. This is why bacteria and fungi have to be minimised in conventional metalworking fluid emulsions. Moreover, primary bacteria also prevent the growth of undesirable fungus and bacteria that are bad for the emulsion and the user. This concept is extremely sound and makes an important contribution to keeping the workplace healthy and safe.

Blaser Swisslube, Switzerland, manufactures an extensive range of highperformance cutting fluids and cutting oils suitable for almost all machining operations and materials. Blaser Swisslube metal cutting fluids do not contain bactericide. Swisslube has already started working towards the REACH compliance, which is a highly strict upcoming norm in Europe. The Indian subsidiary, Blaser India, also manufactures the abovementioned cutting liquids.

Say Yes to Cutting Fluid Without Bactericide! No tankside addition of bactericides

No hazardous chemicals

Reduces corrosion

Conclusion While metalworking fluids are one of the significant ingredients of smooth machining, they are also a source of various health ailments on shop floors. With the increasing emphasis laid on the reduction of carbon footprints and adoption of green processes, this technology could prove to be extremely fruitful.

Solution Provider Blaser Swisslube, Switzerland

Chip compacting

Recycling is a concept we are all familiar with, but seldom must you have thought that incorporating such a simple notion could help cut down costs involved in the machining process. Here, we talk about having a proper chip and oil recovery management system in place, which provides substantial savings, frequently involving a rapid return on investment. In machine shops, there is a considerable amount of chip formation during the machining process along with the use of cutting fluids in the processes. These chip and fluids can be recovered and utilised to positively affect your overall business.

hip compacting, which results in the reuse of compacted cakes and the oil recovered, is a process with numerous advantages including the reuse of metal scrap, which would otherwise be disposed of into the environment; recovery of precious oil and better management of chip waste. Interest in the chip compacting technology further increased because of ever increasing pressure from civic authorities on mechanical waste disposal and its harmful effects on the environment.

THE GREEN QUOTIENT The chip compactor machine is said to contribute to climate change mitigation by recycling mechanical waste, which is reused in the system in the form of cakes. This is oil that could otherwise cause considerable damage to the environment if simply dumped. The cakes, as opposed to chips, give more yield of metal when melted—around 5–15% more metal after melting cakes as opposed to chips reuse of waste oil. The other advantages of cakes include reduction in the space that they occupy on shop floors, ease of transportation and cleanliness maintained on shop floors.

The chip compactor machine is said to recover 90% of the oil that is reused.

UNPLUGGING CHIP COMPACTING Chips are a by-product of machining processes such as turning, milling, drilling, etc. The chips are nothing but metal scrap from steel, cast iron, aluminium, bronze, etc. The chip compactor machine converts these chips into briquettes (cakes) at a pressure of 1000– 2000 kg/cm2. Once the cakes are formed, they can be melted by foundries for metal. While compacting, the machine also recovers

the oil from chips (each drop of oil is important), which is drained into a tray. This oil can be reused after filtration. The machine uses no additives for compacting and is a simple plug & play machine. No separate construction is required for mounting the machine and human intervention is minimum. The hopper arrangement is changed according to the size and shape of chips.

IMPLEMENTING THE TECHNOLOGY Yuken India Ltd (YIL), manufacturer of oil hydraulic equipment in India, was one of the first few companies to develop the chip compacting machine. Over the past few years, Yuken has supplied machines to automotive and auto ancillary companies such as Bajaj Auto (Aurangabad), Maruti Suzuki, Suzuki Power Trains, Toyota Kirloskar Autoparts, Ashok Leyland and Anant Enterprises.

Say Yes to Chip Compacting! Recovery of valuable cutting oil/coolant: Aluminium chips carry 20–30% and Copper/Brass carry upto 10% coolant by weight þ Increased metal scrap value: Aluminium: 25–100%; Copper/Brass: 50%; Cast Iron/Steel: 5–10%

Improved plant air quality

Reduced injuries associated with sharp metal scrap þ Reduced scrap transportation cost þ Freeing up of valuable manufacturing space þ Meeting safety/statutory regulations

Availing special depreciation (50%) (Recycling investment saves energy) þ

Conclusion The recycled materials that the industry processes into raw material feedstock every year are used for manufacturing around the world. Recycling scrap metal reduces greenhouse gas emissions and uses less energy than making metal from virgin material. Organisations recycling scrap and oil would save cost and energy in the bargain.

Solution Provider YUKEN INDIA LIMITED (YIL)

Pro-active maintenance

We all are well aware of the veracity of the phrase ‘Prevention is better than cure’, aren’t we? Staying true to this viewpoint, Pro-Active Maintenance is a system or scheduled maintenance process that keeps the production system healthy. It is actually a life extension system, which supplants the philosophy of ‘Failure Reactive’ with the ‘Failure Pro-Active’ approach by preventing the conditions that lead to machine faults and degradation.

A WORLD OF

DIFFERENCE!

he Pro-Active Maintenance technique comprises actions that abolish the root cause of failures and not just symptoms. Pro-Active Maintenance is now receiving recognition as the only means to reduce and save the burgeoning maintenance cost, extend the performance life of systems and conserve oil & energy without much expenditure on the system or equipment.

UNPLUGGING PRO-ACTIVE MAINTENANCE

The increasing number of breakdowns is a clear indication of the necessity of Pro-Active Maintenance. In the absence of the Pro-Active Maintenance technology, the normal approach is ‘Failure Reactive’ rather than ‘Pro-Active’. If the contamination is not controlled and removed from the system, the oil becomes contaminated and loses its properties, resulting in the need to replace the oil. The disposal of discarded oil also damages the environment. Furthermore, contaminants enter the gaps/clearance between the moving parts, as a result of

which the parts start scoring, damaging and restricting the movement. This leads to malfunctioning, loss of production, loss of energy and frequent breakdowns. Keeping the system fluid clean and free from contamination (dirt, moisture/water and heat being the main contaminants in the system fluid) by adopting the systematic approach to Pro-Active Maintenance can keep the plant, machinery and system healthy. This will also extend the life of hydraulic and lubrication systems and components manifold and improve the efficiency, performance and productivity of the plant, machinery and systems, thus conserving energy and expensive oil. The oil filtration-cum-analysis machine also displays the contamination level according to ISO 4406:1999 through a reliable German online laser particle counter, without shutting down the machine or the system. The unit provides filtration, flushing and transfer of oil from bulk containers to the oil reservoir (or vice versa) and it filters & monitors the oil during transfer itself. The unit removes particulate and water contamination from the fluid most effectively.

Over 75% of the breakdowns and maintenance expenses in any industry are a direct result of hydraulic and lubrication oil system failures, often attributed to excessive contamination levels in the system.

OFF LINE FILTRATION - A TOOL FOR PRO-ACTIVE MAINTENANCE

Off -line Filter 3 to 10 micron Rating with an Option of Water Removal

Off- Line Pump & Motor

Primary Filter Integrated with Magnetic Filter

Duty cycle. Pump on load continously meeting the flow demands with pressure compensated control.

IMPLEMENTING THE TECHNOLOGY l After Nippon Steel, Japan, implemented the Pro-Active Maintenance programme plant-wide, involving contamination control, both improved filtration & rigorous fluid cleanliness monitoring, and pump replacement frequencies were reduced to one-fifth and the cumulative frequency of all failures related to wear and contamination was reduced to one-tenth. After a three-year study, Nippon Steel reported that it successfully achieved a 50% reduction in the bearing purchase plant-wide owing to the implementation of Pro-Active Maintenance technology in the lubricating systems involving both journal and roller bearings and maintaining the system fluid through proper contamination control programmes. l Kawasaki Steel, Japan—not to be outdone—implemented a similar Pro-Active Maintenance programme and achieved an almost unbelievable 97% reduction in hydraulic component failures. l Crane-Bel International P Ltd, based in Delhi NCR, developed an innovative and revolutionary portable oil filtration-cum-analysis machine with in-built contamination monitor and water removal options. The product has proven to be an economical and efficient way to protect the hydraulic and lubrication oil system from the damages that can be caused by contamination and it increases the life of pumps, valves and actuators by three to five times and even more.

THE GREEN QUOTIENT The Pro-Active Approach, in place of the Failure Reactive Approach, brings about the following significant results: l Up to 90% savings on oil procurement and environmental protection l Savings on power bills l Protection and retention of additives to avoid deterioration of hydraulic and lubrication oils, thus preventing degradation of oil l No undue wear and tear of parts & components and saving on maintenance cost l Manifold increase in the life of systems, resulting in huge savings for the procurement of costly hydraulic pumps and systems l Increased efficiency of machinery and systems, resulting in higher productivity, higher profits, competitiveness and growth of business l A clean and healthy environment, ecological balance and protection of lakes & rivers

Say Yes to Pro-Active Maintenance! No breakdown

þ No unscheduled maintenance þ No loss of production þ Improvement in efficiency Increase in operational life and performance

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Conclusion The oil filtration-cum-analysis machine, with in-built contamination monitor and water removal options, is an indispensable tool for on-site pro-active life extension maintenance of hydraulic and lubrication system. It removes all types of contamination.

Sound enclosures

Shhhhh...

Manufacturing in PROGRESS Were you aware that in industrial environments, reverberation and reflected noise from machinery can easily exceed statutory limits and cause serious health risks to the production staff? Help is at hand with specially developed sound enclosures that effectively help reduce noise pollution in industrial operations.

oud noise is a type of pollution that often causes much public concern. Noise health effects are the consequences of elevated sound levels. Elevated noise in the workplace can cause hearing impairment, hypertension, ischemic heart disease, annoyance and sleep disturbance. Changes in the immune system and birth defects have been attributed to noise exposure.

Therefore, it is important to take the necessary steps to control this nuisance. Noise can originate from the use of vehicles, construction work and industrial machines. In order to address noise pollution, methods of mitigating the noise at the source need to be developed. This requires in-depth research and development. One immediate way, however, of controlling noise pollution is the use of sound enclosures.

Unplugging Sound Enclosures Sound waves are absorbed by porous material such as perforated sheets and other objects. Just as putting cotton plugs in the ears reduces the noise level for the individual concerned, sound barriers placed around the source of origin of loud noise drastically reduce the intensity of sound on the other side of the obstacle. For example, loud noise in picture halls and auditoria escapes out because of the effective sound proofing and acoustic techniques applied. The same principle can be applied to industrial units as well. Sound or Acoustic enclosures reduce noise pollution from noisy plant & machinery without reducing the efficiency or cleanliness of the plant during normal operations. Acoustic enclosures can be in the form of panels, doors and windows constructed around a noise source so as to contain the noise of the machinery. Sound absorptive panels prevent the build-up of noise and reverberation inside buildings. The panels can attach to walls or hang from ceilings as baffles. Acoustic doors contain reduced noise emissions from production areas and prevent noise pollution problems from affecting nearby communities. Acoustic windows allow visual access to monitor production lines and manufacturing processes at a safe distance from noisy machinery & equipment. Various ranges & properties of panels can be developed using insulated and sound dampening material, such as sound dead steel, to achieve the desired dB (A) level. A combination of isolation material and absorption material are used, wherein absorption materials absorb the sound waves and isolation materials act as sound barriers. The selection of suitable material combinations depends upon the machinery, noise level and vibration frequency. Absorption materials include glass wool, rock wool, sandwiched coir boards and special polyurethane foams, while isolation materials include polyurethane pads, nylon pads and polymer rubber pads.

The ISGEC Tandem line with Klad On enclosure

According to the Central Pollution Control Board, the maximum limit of noise in an industrial area is 75 dB (A).

Say Yes to Sound Enclosures! For better work environment For better productivity

þ þ

‘Quiet’ Tooling Quiet tooling is a noise control measure, which can be effective on older as well as new machines. This type of tooling has an optimised shear angle at the tool face and may have other noise-reducing features such as vibration damping rings. Noise reductions over standard tooling of up to 10 dB (A) are claimed, although this will depend on operating conditions. The machine supplier should always be consulted about the potential of using quiet tooling; wherever possible, it should be offered on a standard basis in new machines.

The Green Quotient Sound enclosures help promote better working conditions. In fact, in metal forming machinery, a noise level reduction from 100–110 dB to 70–75 dB can be achieved. The main benefit of mitigating sound pollution is better work environment for personnel. Nervous system disorders such as hypertension and heart diseases can be averted in people. Quiet workplaces also result in less leave of absences owing to health reasons and better overall productivity.

Implementing the Technology Applying noise control measures to existing machines can involve simple modifications, although occasionally, it may require expert advice from press suppliers, trade associations or noise consultants. Klad On Design, a Bengaluru-based company, developed sound enclosures for a number of applications including industrial machinery. Sound enclosures on industrial machinery not only help in mitigating noise but also help contain lubrication spray and high temperature waste chips that can be detrimental to human health. ISGEC Heavy Engineering Ltd, Haryana, manufacturer of presses, has presence in more than 21 countries.

Conclusion A quiet environment simply amplifies a positive working condition. In addition, industrial workers for long have been facing various health issues due to continuous exposure to noisy environment. With changing times, industrial shop floors also have undergone a drastic change—controlling noise pollution certainly tops the chart.

Solution Provider Klad On Design

Inverter and servo controlled motors

n todayâ&#x20AC;&#x2122;s scenario, where the power situation has become grim and power cuts have become the norm, the availability and cost of energy have become prime concerns for the industry. To meet the gap between demand and supply, the Indian government will have to make large investments in a short period of time. Even in the machine tool industry, manufacturers are becoming increasingly aware of the high energy costs. Take for instance the machine tool builders who participated in the Blue Competence Machine Tools initiative in Europe. They committed themselves to

optimising the use of energy and other resources to enable faster, better and higher quality manufacturing in end-user industries. They believed that the production technology and equipment supplied by the machine tool industry is the key enabler of resource-efficient processes in all other manufacturing industries. In the machine tool industry too, substantial energy saving has been achieved. The objective of using inverter and servo motors in hydraulic power packs rather than conventional induction motors is to introduce end users to lifetime benefits rather than payback period.

Solution for India has a huge population of machines with potential for substantial energy saving. Inverters and servo motors in hydraulic power packs help this cause by saving energy, which can then be used for industrial growth. This helps reduce the investment in infrastructure and results in considerable socio-economic benefits.

A calculation illustrating the benefits of inverter drives in terms of energy saving

18.5

`2590

In this technology, substantial energy saving can be realised by attempting to decrease the rotating speed of electric motors during processes that require low power. For controlling the rotating speed of the motor, either variable frequency drives or servo drives with synchronous motors are used. 14.8 `2072

Conventional Motor

Power consumed (kW)/day (i.e. in 20 hours)

Inverter Drive

Total cost per day (`) (Cost - `7/kWh)

An inverter drive results in 20% saving. In the case of Yuken, this implied a saving of `189,000 every year. Apart from Yuken India, Micromatic Grinding Technologies Ltd India also uses servo motors on grinding machines for better energy optimisation. In addition, M/S Electropnematics Ltd, Pune, offers controller and feed motor packages that are in use on their servo control presses.

Unplugging Inverters and Servo Controlled Motors

Drive source: Hydraulic units require a wide range of low to high power levels for different processes during one cycle. These processes are achieved by using different actuators, but the hydraulic power source uses either one or two. The energy saving level depends on the pump operation. These systems can achieve the maximum operating efficiency and energy saving by controlling their operation so that the net power required for each process (similar to the required flow and pressure) is achieved. Hydraulic pumps: If the pump flow is fixed, the flow above the required control level is wasted energy. However, if the pump is variable displacement, it can control the hydraulic power source flow. Variable displacement pumps can substantially reduce the energy consumption as compared to fixed displacement pumps. Electric motors: Induction motors have been widely used as the source of rotational energy for hydraulic systems. They basically operate at a constant rotating speed. Their rotating speed (N) is determined by the number of poles.

Using Inverters and Servo Motors can help realise over 64% energy saving.

The Green Quotient The main benefit of an inverter drive is energy saving. The instance below illustrates the extent to which an inverter drive can save costs.

Energy Conservation Implementing the Technology YUKEN INDIA LIMITED (YIL), manufacturer of oil hydraulic equipment, has experienced tremendous energy saving by employing this technique.

Energy consumption KWh

The graph below shows the energy savings i.e. 64% with the retrofitment of the inverter drive.

0.77

Energy Saving 64%

0.28 Without Drive

With Drive

Energy savings comparison- Conventional motor vs. Inverter Drive

Conclusion A penny saved is a penny earned. Going forward, inverter and servo controlled motors for hydraulic power units are the solution for substantial energy conservation in every industrial unit.

Rapid prototyping

MATCHED to Perfection!

As a prospect, how does reducing two-third of your production cost sound? Near-net shape is an innovative industrial manufacturing technique that assists manufacturers in realising this. As suggested by its name, in this technique, the initial production of an item is highly close to the final (net) shape. This feature reduces the need for surface finishing. Rapid Prototyping (RP) is one among the many near-net shape manufacturing technologies. Today, this technology is used for a wide range of applications and is even used to manufacture production-quality parts in relatively small numbers.

UNPLUGGING RAPID PROTOTYPING

In 2012, an 83-year-old patient with a serious jaw infection became the first person to receive a completely 3D-printed titanium lower jaw implant.

Econolyst

Rapid prototyping can be defined as a group of techniques used to quickly fabricate a scale model of a physical part or assembly using three-dimensional (3D) Computer Aided Design (CAD) data. Back in the day, construction of the part or assembly was usually done using 3D printing technology. The first techniques for rapid prototyping became available in the late 1980s and were used to produce models and prototype parts. At present, there are at least half a dozen proven RP technologies available in the market that can produce parts with complex geometry using plastics, metals and paper.

THE GREEN QUOTIENT The family of net shape (or near-net shape) manufacturing technologies inspires manufacturers to look at production methods that create an item or component as near as possible to the final (net) shape, thereby avoiding scrap-intense finishing operations such as conventional machining and grinding. These methods are ‘subtractive’. To produce a part, one must cut or grind away material, which typically creates greater weight in scrap than the final part or component itself. Using Rapid Prototyping for near-net shape metal parts opens up the possibility of reducing material usage, which could enable overall reduction in the cost and greenhouse gas emissions related to manufacturing.

IMPLEMENTING THE TECHNOLOGY The photographs below depict two laser-sintered nylon tools. The negative tool to the left was made completely out of nylon, while the one to the right consisted of a backfilled shell. The surface quality of the tools was good, although they were not finished. Also, no stairsteps were visible. About 25 deep drawings were produced in the negative version. The maximum pressure was 700 bar and a lubricant was used. At 450 bar, a well-formed part was produced, barring the 3 mm small radius of the flangings. Furthermore, the parts made in the positive tool even had well-formed flangings. The comparison of the economically relevant data showed that the shell version needed the same working time and was 10% cheaper when compared with the reference process NC milling (The solid version used more than three times the lead time and increased the costs by five times).

FIVE BASIC STEPS FOR CREATING PROTOTYPES: l Create a CAD model of the design l Convert the CAD model to the STL format l Slice the STL file into thin cross-sectional layers l Construct the model one layer atop another l Clean and finish the model

Say Yes to Rapid Prototyping! Helps identify design errors

Is Cost-effective

Helps boost innovation

Increases visualisation capability

Conclusion Rapid Prototyping helps identify errors in the physical functioning or ergonomics of components and products. This, in turn, saves the time taken for redesigning and reiterating the entire production cycle, thereby significantly reducing the costs incurred on repeating the process.

Friction stir welding

Connecting the Dots Welding and joining technologies are fundamental to engineering and manufacturing. Without the ability to make strong and durable connections between materials, it would be impossible to produce the many different items we all rely on in our everyday lives—from the very large (buildings, pipelines, trains and bridges) to the very small (medical implants and electronic devices). However, it is equally important that the welding process uses less energy and does not release harmful gases & radiation.

riction Stir Welding is an ecofriendly process to weld and produce near-nano-grain-sized materials. It is a relatively new solid-state joining process that has been used across the segment. It is also useful for joining

high-strength aerospace aluminum alloys and other metallic alloys that are hard to weld using conventional fusion welding. This environment-friendly technology is considered to be the most significant development in the metal joining process.

Unplugging Friction Stir Welding Friction Stir Welding involves the joining of metals with low melting points without fusion or filler material. The welds are created by the combined action of frictional heating and mechanical deformation by using rotating tools. A rotating tool with a central probe is pressed into the joint and traversed along the weld line. Frictional heat, generated mostly under the tool’s shoulder, softens the material. The shoulder also acts to contain the softened material, which is forced to the back of the tool, becoming consolidated in the process to form a solid phase weld. Provided the components are adequately restrained, a high-quality solid phase weld is formed following considerable hot working of the material at the joint. Friction Stir Welding is most suitable for aluminium components, which are flat and long.

Friction Stir Welding

Say Yes to Friction Stir Welding! Produces no smoke, fumes or arc glare Low environmental impact

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Friction Stir Welding was invented by Wayne Thomas at The Welding Institute (TWI), UK, in December 1991. The Welding Institute holds patents on the process.

of GROWTH

The Green Quotient Friction Stir Welding is an environmentally cleaner process due to the absence of the need for various gases that normally accompany fusion welding. Further, no consumable filler material or profiled edge preparation is normally necessary. Following are the ‘green’ positives of this technology:  No filler wire or shielding gas requirement for aluminium alloys  No fume, spatter, UV radiation  Uses machine tool technology  Easy to automate—reduces the need for skilled welders  Energy efficient

Implementing the Technology ETA Technology is a leading Indian manufacturer of friction welding and friction stir welding machines with international presence. Producing more than 20 machines every year, the company is a global supplier of machines to a wide spectrum of industries. The friction stir welding machines can be used in drive axle housing and trailer axle housing, propeller shafts, valves and other applications.

Conclusion Manufacturers are under increasing pressure to produce stronger and lighter products whilst using less energy and environmentally harmful material, at lower costs. Friction Stir Welding, being a solid state, low energy input, repeatable mechanical process capable of producing welds with high strength in a wide range of materials, offers a potentially lower cost, environmentally benign solution to these challenges.

Solution Provider ETA Technology

Hydrocarbon cleaning

Cleaning it

Green The cleaning of inserts is often done using waterbased cleaning systems. Under such systems, in order to remove a very small portion of oil from the discharged water, the pH levels of water have to be reduced, the oil has to be skimmed and then the pH levels have to be increased again. This creates various problems and has caused considerable wastage of water. Here, the Hydrocarbon Cleaning technology comes into play as a solution to this problem. It is a feasible technology with many advantages over waterbased cleaning.

ydrocarbon fluids have been extensively used for a wide variety of industrial cleaning applications and can be used in place of chlorinated solvents, mineral spirits and kerosene-based cleaners. The technology is environmentally safe, non-hazardous, with biodegradable formulation for use in removing fresh and aged petroleum hydrocarbons. For instance, Hydrocarbon Cleaning systems from Dürr Ecoclean have been successfully used for many years—some for very demanding cleaning jobs—in the finest cleaning environments.

Unplugging Hydrocarbon Cleaning In the Hydrocarbon Cleaning technology, cleaning is done using hydrocarbon-based machines that do not consume any water. Therefore, there is also no discharge of water to the ETP. This technology uses a solvent-based cleaning system that uses non-halogenated hydrocarbons as highly effective cleaning media, allowing for the safe and economical use of solvents for removing oils, greases, emulsions and swarf between or after manufacturing processes.

Even though this technology does not use water-based cleaning media, it effectively cleans grease, grime and swarf.

Say Yes to Hydrocarbon Cleaning! Uses a solvent-based cleaning system Allows safe and economical use of solvents for removing oils Cleaning and drying processes save heat energy Minimal vapour loss, emissions and humidity issues Heat recovery in the entire process helps reduce energy input Results in monetary benefits

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Some Key Features of Hydrocarbon Cleaning: This cleaning technology has several environment-friendly features. The cleaning and drying processes take place in a work chamber under vacuum, thus saving heat energy and minimising vapour loss, emissions and humidity issues in shops. In addition, heat recovery throughout the entire process helps reduce energy input. The solvent in the system is constantly reclaimed and separated from the cutting oil. The solvent used to wash the parts is never returned to the wash tank until it has been separated from the oil through the distillation process. The solvent is thus always pure while washing parts.

The Green Quotient • • • • •

Better energy efficiency due to heat recovery system Free of emissions Excellent drying properties unlike water-based cleaning Does not require expensive disposal systems Easy to separate from oil via distillation

Implementing the Technology Dürr is one of the world’s leading suppliers of products, systems and services, mainly for automobile manufacturing. It also delivers cleaning and filtration systems for the manufacture of engine and transmission components as well as balancing systems and products for the final vehicle assembly. The Dürr Ecoclean Compact 80C is a solvent-based cleaning system that uses non-halogenated hydrocarbons as highly effective cleaning media. This machine is presently being used by Taegutec India for its cleaning operation involving inserts and has brought about several benefits apart from effective cleaning.

Conclusion Hydrocarbon cleaning can certainly prove to be a highly effective cleaning media, which is safe, economical and, of course, environment-friendly.

Solution Provider Dürr Ecoclean

Energy savings through Kaizen

r o f e g n Cha

! r e t t e B the

e view age. With th rt o h s y le, rg e nner possib today is en a y m tr e s v u ti d c in e st-eff ergy. for the the most co nserving en in ry concerns o a c e g m in ri ta n s p e a e iz w s a th One of ate energy ed activitie tential of K o is in p m rd e li a e d th n d g n ta in a s nt of bout recognis to minimise improveme s to bring a ustries are e n d o th in ti h a re g is o u n m a ro aste th d in org more and liminate w n been use e e ft to o s s a h im s a s proce Kaizen . The Kaizen s e s s e c ro p . and provements im l ta n e m environ

aizen—Japanese for ‘improvement’ or ‘change for the better’—refers to philosophy or practices that focus on the continuous improvement of processes in manufacturing, engineering, game development and business management. This concept has been applied in the areas of healthcare, psychotherapy, life-coaching, government, banking and other industries. When used in the business sense and applied to the workplace, Kaizen refers to activities that continually improve all functions, and involves all employees from the CEO to the assembly line workers. It also applies to processes such as purchasing and logistics, which cross organisational boundaries to enter the supply chain.

Unplugging Kaizen

Inserts before Kaizen Implementation

Inserts after Kaizen Implementation

Energy Kaizen is a detailed energy-use assessment with immediate implementation of energy reduction opportunities. In Energy Kaizen, a cross-functional team of employees identifies and implements process changes to reduce waste such as idle time, inventory and defects. Kaizen events create important windows of opportunities to eliminate energy waste. An example of the Kaizen process being implemented in a cutting tool manufacturing company while loading carbide inserts on a tray for sintering was observed. Initially, 50 batches were required to produce 400,000 inserts. The total energy spent was 17,500 kWh and the total cost summed up to `227,500. However, through Energy Kaizen, changes were introduced in loading inserts on the tray. This change in pattern allowed a greater number of inserts to be loaded onto the same tray. Thus, for the same 400,000 inserts, only 47 batches were required. The energy saved was 1050 kWh and the amount saved was `161,910.

Kaizen was first implemented in several Japanese busine sses after the Second World War.

The Green Quotient Reduces waste in areas such as inventory, waiting time, transportation, worker motion, employee skills, over production, excess quality and in processes Improves space utilisation, product quality, use of capital, communication, production capacity and employee retention Provides immediate results. Instead of focusing on large, capital-intensive improvements, Kaizen focuses on creative investments that continually solve a large number of small problems. Large, capital projects and major changes will still be needed, and Kaizen will improve the processes of capital projects, but the real power of Kaizen lies in the ongoing process of continually making small improvements and reducing waste.

Implementing the Technology Taegutec India, the second biggest cutting tool manufacturer in the world, has won several awards for its green initiatives. Taegutec has achieved tremendous energy saving by implementing Kaizen on its shop floor through extensive energy audits.

Say Yes to Kaizen! Understand how energy is used in a particular process Brainstorm opportunities to reduce energy use in that process Implement those ideas in a short time frame

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Conclusion Among various methods of energy management, Kaizen has proved to be one of the most successful methods that conserves energy in the most cost-effective manner.

Solution User Taegutec India

FACTS and

Figures A clamping device made of carbon fibre instead of steel is as much as 66% lighter, stronger and even more rigidâ&#x20AC;&#x201D; with identical clamping force values.

In 2012, an 83-year-old patient with a serious jaw infection became the first person to receive a completely 3D-printed titanium lower jaw implant.

Kaizen was first

implemented in several Japanese businesses after the Second World War.

Studies in drilling have shown that reducing the edge hone to create a sharper drill can reduce the cutting temperature by 40%.

Friction Stir Welding was invented by Wayne Thomas at The Welding Institute (TWI), UK, in December 1991. The Welding Institute holds patents on the process.

MWFSAC, in its final report in 1999, recommended that the exposure limit to fluids be 0.5 mg/m3 and made medical surveillance, exposure monitoring, system management, workplace monitoring and employee training mandatory in order The costs associated with the use of to monitor workersâ&#x20AC;&#x2122; exposure to metalworking fluids. cutting fluids are estimated to be several billion dollars every year.

Both water soluble and nonsoluble petroleum-based fluids eventually lose their efficiency and have to be disposed of, and the disposal methods used are often environmentally unsound.

Friction Stir Welding is most suitable for aluminium components, which are flat and long.

The chip compactor machine is said to

Kaizen reduces waste in areas such as inventory, waiting times, transportation, worker motion, employee skills, over production, excess quality and in processes.

Inverter and Servo controlled motors can help realise over 64% energy saving.

recover 90%

of the oil that is reused.

According to the Central Pollution Control Board, the maximum limit of noise in an industrial area is 75 dB (A). Conventionally, the power used during the cutting process forms only 25% of all the power consumed by the machine. The first techniques for rapid prototyping became available in the late 1980s and were used to produce models and prototype parts. An Inverter drive results in a saving of 20%. In the case of Yuken India Ltd, this meant a saving of `.89 lakh every year. The use of MQL leads

to a 13% decrease

in overall costs as well as better cutting tool life.

Indian Plastics Sector

ndia has made significant economic strides and is one of the leading emerging markets in the world. On the basis of purchase power parity, it is one of the top five global economies. Plastics is one of the fastest growing industries in India. In fact, the Indian plastics industry is expanding at a phenomenal pace. Major international companies from various sectors such as automobiles, electronics, telecommunications, food processing, packaging and healthcare have set up large manufacturing bases in India in an attempt to address the increasingly rapid demand for plastics. At present, the domestic plastics processing industry is highly fragmented and scattered. There are more than 25,000 manufacturing units, most of which are small scale industries. The medium scale operators produce almost 60% of the total production, while the unorganised sector â&#x20AC;&#x201C; with 40% of the balance production â&#x20AC;&#x201C; remains an important player. The total capacity of the industry to process polymers is estimated at over 5 million tonne per annum. Furthermore, about 2 million tonne of plastic materials is recycled into different value-added products. Thus, the total consumption of polymers/plastics (including the recycling segment) is about 7 million tonne per annum. The potential in the Indian market has motivated Indian entrepreneurs to acquire technical expertise, achieve high-quality standards and build capacities in various facets of the booming plastics industry. Phenomenal developments in the plastics machinery sector coupled with matching developments in the petrochemical sector (both of which support the plastics processing sector) have facilitated plastics processors to build capacities to service the domestic market. It has been recognised that current waste disposal and sustainability practices need to be strengthened for the Indian plastics industry to retain its competitive edge. The technologies based on recycling, including energy recovery by incineration, should be complemented by environmentally degradable plastics, and sustainable polymeric materials should replace the conventional commodity plastics in segments where recycling is difficult. The subsequent pages of this document describe plastic manufacturing technologies that promote the environment using safer materials and processes. In this section, UNIDO-ICAMT aims to provide the Indian plastics sector, particularly the Micro, Small and Medium Enterprises (MSMEs), a guide to adopting technologies that not

Indian

Plastics Sector

Vijay Merchant President, Indian Plastics Institute

It is heartening to note that an effort is being made to promote ‘green initiatives’ in our plastics sector – a progressive and responsible sector in our economy. Plastics are already helping businesses and consumers across the world to conserve natural resources, improve energy efficiency, reduce waste, protect human health and support livelihood in several ways. Plastics also have a huge potential to help address several crucial issues of climate change and to meet the challenges of sustainable development. If we seriously want to think long term in our attempts to conserve resources, minimise pollution and yet meet the demands of a growing population, we need to not only think differently once in a while but also embrace the green culture as a religion. I am sure that this book ‘Green Shoots’ will motivate and encourage readers connected with our industry to think green, progress and prosper. At the same time, I believe that this initiative will help improve the quality of life across all income groups in the developed and developing states to ensure a better and healthier tomorrow. This sharing of real-life situations and eco-friendly practices adopted by players and stakeholders would help readers in their endeavour to lower the impact on the environment.

Injection moulding machine IN AN

energy-efficient

avatar When 30% of all plastic products are produced by using the injection moulding process, it is evident that energy-saving practices need to enter this segment. What if these new practices achieve energy efficiency by also improving repeatability, reducing noise and wear & tear and lowering oil temperature?

Environmental benefits

screw run

hold

injection

clamp close

ejector back

80.0

ejector fwd

Power (kw)

100.0

cooling

120.0

clamp open

l Usage of Variable Frequency Drives (VFDs) and servo drives in IMMs can result in significant energy savings l VFDs and servo drives can be retrofit on conventional machines, making it easy for manufacturers to implement this energy-saving technology

kcol

njection moulding is a manufacturing process for producing parts from thermoplastic and thermosetting plastic materials. Material is fed into a heated barrel, mixed and forced into a mould cavity where it cools and hardens to the configuration of the cavity. After a product is designed, usually by an industrial designer or an engineer, moulds are made by a mould maker (or tool maker) from metal, usually either steel or aluminium, and precision-machined to form the features of the desired part. Injection moulding is widely used for manufacturing a variety of parts, from the smallest component to entire body panels of cars. Injection Moulding Machines (IMMs) are classified primarily by the type of driving system used – hydraulic, mechanical, electric or hybrid. In the average IMM, up to 70% of electricity is consumed by peripheral machinery. Energy can neither be created nor destroyed; therefore, it is important to identify where the unused energy goes during the moulding process. Typically, this energy goes into three places: 1. Heating the machine’s hydraulic oil 2. Noise 3. Wear and tear on the machine’s hydraulic system The heating of hydraulic oil explains the need for a cooling tower, ie electricity is first used to heat the oil and subsequently used to cool that oil down. A significant amount of hydraulic oil that is pumped and pressurised to run the machine is not used, but dumped back into the tank through a relief valve. The valve, equivalent to a mechanical brake, converts energy into heat. Sources of excess energy consumption are as follows: • Fixed frequency power supplied by the electrical utilities • Operation of synchronous motors used to drive the hydraulic pumps in almost all IMMs If machines always operated at full capacity (clamp open, close, injection and screw charge at 100% with no cooling time), there would not be a problem. However, machines rarely work at full capacity. This leaves an opportunity to save electricity if there is a way to pump the oil needed by the machine. This was difficult in the past, but with the introduction of the AC inverter drives, a remedy to conserve energy can be incorporated during plastic moulding.

speed = 100% speed control

60.0 40.0 20.0 0.0 0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

Elapsed time (sec) Difference between the power consumption of a moulding machine with (magenta) and without (blue) a frequency controller

45.0

50.0

In the average IMM, up to 70% of electricity is consumed by peripheral machinery. Hair combs and buttons were one of the first products manufactured by a relatively simple injection moulding machine.

VFD and system controller eliminate the wastage of hydraulic oil and energy associated with it.

Possible solution – energy conservation Variable Frequency Drive (VFD)/AC Inverter Drive Recognising the wasted energy and control difficulties created by conventional motors, the electronics industry invented the AC inverter drive or VFD. The VFD controls frequency of AC electrical power and in turn can control the speed of a synchronous motor. This motor can be slowed down, thus increasing the efficiency of a moulding machine. To eliminate wastage of hydraulic oil and energy, two major components, namely, a system controller and an AC inverter drive or VFD are required in the moulding machine. The basic principle behind implementing a VFD and system controller is to eliminate not only wastage of hydraulic oil but also energy associated with it. This is done by simply not pumping the oil if it is not required. Advantages of implementing a VFD l Energy savings l Better repeatability l A quieter machine l Lower oil temperature l Less demand on cooling tower l Less wear and tear on the machine

Signals from machine’s controller (relay or solid state)

Drive system controller

AC power at 12 to 60 Hz depending on machine’s requirements

Role of AC motor controllers in energy efficiency A Sinusoidal Motor Efficiency Controller (SinuMEC) is a new category of AC motor controllers that uses the right voltage to improve efficiency of variable load motors running at constant speeds. Built around patented technology, the SinuMEC provides a pure sinusoidal voltage wave form when the motor starts and during normal operation. SinuMEC continuously monitors the power consumption of the motor and reduces the voltage when the motor load decreases, thus enabling improved motor performance and energy efficiency. A SinuMEC installed in a 100 hp plastic injection machine achieves a reduction of 16% in kWh, 42% in network losses, 38% in reactive power and an increase in the lifetime of the expensive machine, as well as increases reliability and reduces costly downtime. A Servo-Drive Pump Motor uses a precisely controlled servo motor to drive the hydraulic pump. Rather than maintaining line pressure, diverting excessive flow and adjusting servo valves, the flow from the pump is directly sent to the rotary or linear actuator performing the machine function. Because the pump is precisely controlled, the speeds of actions such as injection and screw rotation are controlled directly by the servo motor. Pressure limits are easily controlled by limiting the torque of the motor. Because no unnecessary flow is generated, the efficiency of such machines is about as high as a hydraulic machine. In many cases, these machines consume only 30% of the energy consumed by fixed drive pump motors. Servo drives can be used to operate the injection screw, as precision control is often required for the injection step. Significant energy savings are often realised by replacing hydraulics with electric drive systems on IMMs.

Application Fixed frequency AC power, typically 50 or 60 Hz

Power Electronics Systems Drive

Pump motor turns at rate proportional to machine’s requirements Schematic – VFD

Power Electronics Systems introduced the SinuMEC AC Controller, which utilises patented transformation technology, using a specially designed power transformer, electromechanical contactors and a sophisticated controller. The unique architecture enables pure sinusoidal voltage control, while the use of simple components makes the apparatus reliable.

Conclusion Studies have proved that a VFD retrofit can save 20-50% of the power draw of most IMM hydraulic pump motors. Expanding its industrial scope, this technology can also be applied on other hydraulic systems such as die-casting, stamping or other processes. Perhaps lowering the price tag on this technology would lead to even wider adoption among various industry verticals.

Solution providers Ferromatik Milacron India (FMI); Bosch Rexroth India Ltd

49 49

Injection stretch blow moulding

Going

light How does one produce high-quality plastic containers by maintaining energy and material savings at the same time? Giving a fresh perspective to this paradox is Injection Stretch Blow Moulding (ISBM) technology.

he main application of ISBM is the production of Polyethylene Terephthalate (PET) bottles used commonly for water, juices and other products. This process is used for extremely high volume (multi-million) runs of items such as wide-mouth peanut butter jars, narrow-mouth water bottles, liquor bottles etc. In a bid to promote sustainability through eco design, PET manufacturers are looking to incorporate lightweighting technology in their manufacturing methods to save on raw material consumption and energy, not only during the production process but also during subsequent transportation of PET bottles. ISBM being an expensive process, small improvements also imply significant cost reduction during production.

Stretch blow moulding process

After implementing the ISBM technology, Sidel’s NoBottle technology makes PET bottles that weigh a mere 9.9 g. In the US, the number of blow moulded plastic containers for the soft drink industry went from zero pieces in 1977 to ten billion pieces in 1999.

When Enviroclear barrier coating technology is applied to a 500 ml PET or PP bottle, it provides an oxygen barrier of 0.001 cc/pkg/day (42 x’s uncoated PET) and 0.0025 cc/pkg/day (25 x’s uncoated PET).

ISBM is divided into the following stages: 1. Injection: Molten polymer flows into the injection cavity via the hot runner block to produce the desired shape of the preform with a mandrel (the core pin). After a set time, the injection moulds and core pins part, and the preform is held in a neck carrier that is rotated 90°. 2. Stretching and blowing: Stretch blow moulding is similar to injection blow moulding. When conditioned to the correct temperature, the preform is ready for stretching and blowing to reach the desired shape. When the preform is within the blow mould area, the moulds close. A stretch rod is introduced to stretch the preform longitudinally. Using two levels of air pressure, the preform is blown circumferentially. This method produces a biaxial molecular orientation. The specific molecular orientation provides higher mechanical strength, rigidity and transparency of the material. 3. Discharge: After a set time for cooling, the moulds open and the preform is removed via drop chutes or robotics. In practice, these stages are carried out concurrently using a revolving carousel of moulds.

Environmental benefits Manufacturers all over the world are looking at ways of implementing eco design. Lightweight technology helps not only conserve raw material but also energy. This technology implies energy savings on the machines that handle several tonne of bottles per day and on the distribution networks.

Applications Sidel NoBottle technology A standard 500 ml PET bottle weighs approximately 16 g. The world leader in lightweight PET bottles, Sidel has introduced the NoBottle technology where each PET bottle weighs a mere 9.9 g, ie a weight reduction to the tune of 25–40%. Given that in 2007, about 26.5 million bottles of still water were produced, Sidel has estimated that the NoBottle technology has been instrumental in a potential saving of 160,000 tonne of plastic world wide apart from large energy savings. In fact, 40% savings in container weight translate to energy savings for machines that handle several tonne of bottles everyday and for distribution networks that ship packages to their points of sale. Apart from implementing the ISBM technology, Sidel successfully reduced the weight of the PET bottle by introducing greater flexibility of PET. This means that the bottle does not require added robs for strength. Sidel’s Flex technology takes advantage of PET shape memory, ie the ability of PET to bounce back to its original shape after being squeezed or compressed during shipping. Companies working on lightweight PET bottles in India Jauss Polymers Ltd – production of PET bottles on Nissei machines Pearlpet – manufacturers of PET bottles Technopet Machineries – producers of ISBM machines

Enviroclear Barrier Coating Technology In addition to developing lightweight PET containers, manufacturers are looking at ways of extending product shelf life through the application of coatings. Enviroclear barrier coating technology was developed by the Council for Scientific and Industrial Research, South Africa, to extend product shelf life by significantly reducing the penetration of oxygen and the loss of carbon dioxide through plastic packages. When applied to a 500 ml PET or polypropylene bottle, the Enviroclear barrier coating technology provides an oxygen barrier of 0.001 cc/pkg/day (42 x’s uncoated PET) and 0.0025 cc/pkg/day (25 x’s uncoated PET), respectively. When applied to a PET 12 oz carbonated soft drink bottle, the Barrier Improvement Factor (BIF) is 6.4 times for carbon dioxide retention compared with a standard PET bottle. Combined with Container Corporation of Canada’s Enviroclear technology, which can produce a two-stage injection stretch blow mould, clarified polypropylene bottles and wide-mouth jars are as clear as glass and make a viable, economical alternative for hot fill barrier packaging. As the chemistry is benign, the resin identification number designation on the bottom of the bottle does not change.

Conclusion The scrapless process in ISBM signifies that there is no flash to trim and no requirement to regrind. The high-quality injection moulded neck finish allows for biaxial orientation for strength and clarity. This technology is particularly suited for lower volume production applications that suit Indian processors’ requirements.

Hot runners in injection moulds

Channelising

savings

In spite of being around for more than 40 years, processors know very little about the key business advantages of hot runner systems. Lower processing cost, reduction in cycle time, improved moulding system efficiency and balanced melt flow are the merits of this system. By elaborating on this trail of thought, if achieving energy efficiency is your main agenda, then read on to grasp functionalities of this arrangement.

runner is the channel through which resin enters the gates of the mould cavity. By connecting the gate and the sprue channel, a runner conveys the plastic from the barrel of the injection moulding machine to the part. For this system, delivering the melt to the cavities and balancing the filling of multiple cavities and multi-gate cavities are some of its main functions. Reduction in scrap, easy ejection and maximising efficiency in energy consumption are attributes that are closely related to runner systems. With substantial control extended towards filling/packing/cycle time, there are two main types of injection moulds, namely cold and hot runner systems. Types of cold runner moulds 1. A two plate cold runner mould consists of a simple type of mould with one parting plane which is split into two halves. The runner system must be located on this parting plane; thus, a part can only be gated on its perimeter. 2. A three plate cold runner mould has two parting planes situated behind the cavity plate. The second parting plane, between the cavity plate and top clamp plate, provides for a runner to travel under the mould cavity to any position relative to the part cavity.

Runnerless moulds are more advantageous than cold runner systems as they eliminate waste plastics completely.

In 1963, Mold-Masters was the first company to exclusively manufacture hot runners.

Use of a cold runner system results in additional energy consumption as excess plastic separated from the moulded component is reprocessed completely.

Types of runnerless moulds Insulated runner moulds These have oversized passages formed in the mould plate. The passages are of sufficient size such that under conditions of operation the insulated effect of the plastic (frozen on the runner wall) combined with the heat applied with each shot maintains an open, molten flow path. The insulated runner system should be designed such that, while the runner volume does not exceed the cavity volume, all of the molten material in the runner is injected into the cavity during each shot. This helps prevent excessive build-up of the insulating skin and minimises any drop in melt temperature. Compared to a cold runner system, an insulated runner system provides advantages such as reduction in material shear, faster cycle times, elimination of runner scrap, decreased tool wear, improved part finish, less sensitivity to the requirements for balanced runners and shorter cycle times.

Hot runner moulds Hot runners are more commonly used compared to insulated runners. These fall into two categories â&#x20AC;&#x201C; internally and externally heated. Hot runners retain the advantages of the insulated runner system over the conventional cold runner system and eliminate a number of disadvantages. However, its complex mould design, manufacture operation and maintenance requirement are evident hindrances. Its higher costs and thermal expansion of various components also need to be taken into account. These disadvantages are a result of the need to install a heated manifold, balance heat generated by the manifold and the minimisation of polymer hang-ups. It is often cost effective to produce large volumes with hot runner moulds, in spite of high investments. These systems are used for a wide range of applications.

Cold runner systems

In a cold runner mould, the runner is cooled and ejected with the part. In every cycle, a part and a runner are produced. The cold runner mould is a simple and less expensive alternative to hot runner systems. The specialised temperature controllers keep the injection mould components at the design temperature in order to keep the mould material flowing. In addition to their ease of set up and use and less maintenance requirement, achieving colour changes are easy in cold runner systems.

Hot runner systems Hot runners, also called runnerless moulds, differ from cold runner moulds by extending the injection moulding machineâ&#x20AC;&#x2122;s melt chamber and acting as an extension of the machine nozzle. A portion or all of the polymer melt is at the same temperature and viscosity as the polymer in the barrel of the IMM.

Disadvantages of cold runner systems Plastic waste is generated

Environmental benefits Runnerless moulds are more advantageous than cold runner systems. They eliminate waste plastics completely, thus saving raw material. In a cold runner system, this excess plastic is separated from the moulded component to be reprocessed completely, ie it is ground and then used in the injection moulding process for the fabrication of a new component. This results in additional energy consumption.

Runners are either disposed or reground and reprocessed with the original material, adding a step in the manufacturing process Regrind will increase variation in the injection moulding process and could decrease the plasticâ&#x20AC;&#x2122;s mechanical properties

Applications Runnerless moulds are not popular in India owing to their complex mechanism and high costs. However, there are several manufacturers of hot runner systems abroad. These help in producing a range of items from bottle caps to car body parts to mobile telephone components. Hot runner systems can be customised to the specific need of the component manufacturer such that savings in raw material and energy are easily achievable.

Conclusion Before incorporating any of these systems, it is important that the processor specify the mould for a thermoplastic moulding application. By putting forward the cost and part quality advantages, runnerless moulds do come with many options in order to obtain all the moulding efficiencies and part quality benefits. The addition of consistency and more flexibility for moulding automation works in its favour.

Solution providers Synventive, MA, USA; Beaumont Technologies, PA, USA; DuPont Plastics

Upcoming injection moulding technologies

Best

Co-existing at its

Designers of parts for injection moulding have historically been constrained by the need to maintain relatively constant and thin sections in finished products. Co-injection moulding, a method for improving physical properties and reducing raw material consumption, is achieved by injecting two dissimilar materials simultaneously through concentric nozzles. Read on to know more on how this technology is helping processors leverage recycled plastics without compromising on quality.

aintaining constant and thin sections in finished products continues to be a challenge for designers since thick wall sections require a long cooling time and have a tendency to develop sink marks. In such a situation, with co-injection moulding the designer of the part has the opportunity to design parts with an outer skin made of a material with the desired visual or physical properties and to inject an internal core with a material that is less expensive, stronger or lighter. Gas Assisted Injection Moulding (GAIM) The process features a unit that introduces nitrogen gas into a mould cavity after it has been filled with plastic. The compressed nitrogen displaces a portion of the molten plastic when injected into the cavity. The result is hollow parts that are light and relatively inexpensive to make. Designers can use gas assist moulding to create thin-walled parts. Such parts can be moulded with low clamp tonnage, which reduces not only tooling cost and required injection moulding machine size but also raw material consumption. The gas assist technique is ideal for adding thick, hollowed-out sections to

otherwise thin-walled parts. The process improves upon polymer fill and packing techniques and boosts melt-flow length. A designer can create larger, more complex parts with fewer injection gates than conventional moulding, while minimising costs incurred with complicated hot runner systems. In addition, the sections that are cored out cool rapidly, reducing overall cycle time. Water Assisted Injection Moulding (WAIM) WAIM is one of the latest and most promising developments in â&#x20AC;&#x2122;assistedâ&#x20AC;&#x2122; injection moulding. As in the established GAIM process, WAIM technology uses a fluid under pressure to core out a hollow plastic part in the mould. Because of similarities between the two processes, both provide several of the same benefits: lower material costs, lower tool cost and more part consolidation and less finishing than with unassisted injection moulding or metals. The advantage that WAIM has over GAIM technology is that the water can directly cool the inside of the part. The thermal conductivity of water is 40 times greater than that of gas, and the heat capacity of water is four times greater than that of gas.

In co-injection moulding, a low cost core can be used for cost savings.

Improved aesthetic qualities can be achieved by using co-injection moulding.

Benefits of co-injection moulding l l l l l l l l l

Foamed core for reduced weight and noise transmission Combined property characteristics Glass-filled cores for improved physical properties Low cost core for cost savings High gloss skin material over structural core material for combination of aesthetic and structural properties Post consumer recycled material in core Environment-friendly Industrial recycled material in core Reground painted parts recycled into core

Co-injection is the process of injecting two separate materials into the same mould that allows one polymer to be encapsulated by another, one forming the skin, the other forming the core. The multi-layer plywood effect maintains product integrity and performance while allowing for the maximum recycled material content in the industry. This technology can be categorised as follows: Machine-based co-injection moulding The co-injection process requires two injection/processing units. The units generally inject material through a manifold located at the end of the injection barrels. The manifold ports the two melt streams into a centrally located nozzle. The machine controls the injection units

Co-injection technology allows processors to use the maximum amount of recycled material in products without compromising on quality.

to achieve a skin-core-skin flow sequence through the manifold into the mould. Last skin flow is needed to clear the short nozzle section of core material and to seal the gate area with skin. This arrangement can be used on single or multiple cavities, conventional cold runner mould. Mould-based co-injection moulding This same process can be achieved on a hot runner mould by utilising a hot runner system. This system, sometimes identified as ‘Mould-based co-injection’, still utilises two injection units. The two melt streams are directed into the mould via separate channels. These two channels remain separate until they reach the gate area of the part. At this point, they flow through a nozzle arrangement similar to the normal co-injection manifold.

Application In 2007, Cascade Cart Solutions introduced the EcoCart™ to address the growing demand from the solid waste and recycling industry for products containing recycled content. The challenge was how to incorporate a high amount of recycled content into their containers, which are subjected to weekly pick-ups by automated garbage trucks, without compromising their long-term durability. The solution was to use an innovative injection moulding process – co-injection – to layer recycled material (postconsumer resin) in between two layers of virgin plastic. Utilising co-injection technology, Cascade Cart Solutions is able to manufacture an eco-friendly waste and recycling collection cart that contains up to 50% recycled content and carries a third part certification. With the EcoCart™, recycling has come full circle. By making the carts with recycled content, Cascade helps put back what is thrown out, increasing landfill diversion and enabling cities to promote sustainability.

Say Yes to co-injection moulding Lower cost parts Higher strength core Reduced cooling time for lower temperature core Improved aesthetic qualities Conclusion

Combined property characteristics

þ þ þ þ þ

Co-injection technology will allow processors to use the maximum amount of recycled material in a product without compromising on quality. The multi-layer effect will maintain product integrity and performance. The potential of this technology will also give a much needed impetus to the domestic recycled plastics segment.

Solar rotational moulding

Casting in the

sun!

Solar Rotational Moulding (SRM) is the latest in ‘greening’ plastics manufacturing. Unlike conventional rotomoulding that requires electricity or natural gas, SRM relies on free and widely available energy – solar energy. Besides, it does not need bulky equipment and is a more eco-friendly process than conventional methods of rotational moulding.

plastics processing technology for creating imaginative and conventional product lines beckons Indian plastics processors.. Rotomoulding (RM), also called rotocasting, spin casting and rotation moulding, produces hollow forms with a constant wall thickness. Polymer powder is tumbled around inside the mould to produce virtually stress-free parts. A heated hollow mould is filled with a charge or shot weight of material. It is then slowly rotated (usually two perpendicular axes) causing the softened material to disperse and stick to the walls of the mould. In order to maintain even thickness throughout the part, the mould continues to rotate at all times during the heating phase, and to avoid sagging or deformation, even during the cooling phase. In India, although this technique is majorly used in the manufacture of water tanks, many companies in road safety, toy manufacturing and automotive parts systems are applying it. The concern however remains on the technique’s massive appetite for energy. Rotomoulding requires continuous supply of electricity that compels the need for an alternative source of energy. The ideal solution for this task would be to utilise freely available energy. Thus, the exploration of finding greener alternatives begins.

(1) Unload - load station

Mould (open)

Moulded part

Two-direction rotation of mould Counterweight Indexing unit (2) Heating station (3) Cooling station

Mould (closed)

Water spray

Rotomoulding process 56

Typical system costs

SRM: Varies from $ 50k to $ 150k RM: Varies from $ 300k to $ 1M+

One of the first applications of rotomoulding was in the manufacture of doll heads.

Return on investment

Energy cost of finished product

SRM: 15% RM: 9%

SRM: 0% RM: 10-30%

Solar empowerment SRM, also known as solar thermal moulding, uses concentrated solar thermal energy from a heliostat array of sun-tracking mirrors for heat. This heat beam, which replaces energy inputs from fossil fuel sources, can be refocussed depending upon the target. This allows for simplification of the moulding hardware and large savings on the total equipment cost compared to the traditional process. Heliostats are computer-controlled mirrors that keep the energy from the sun focussed on a target as the sun moves across the sky. The heat from the sun directly heats the mould and melts the plastic. Because the process uses heat directly in the moulding process, the system is highly efficient – 75% efficient as compared to typical photovoltaic efficiency of 15% or less. There is no need to convert light into electricity or transport energy via expensive

SRM has numerous advantages over conventional rotational moulding l Usage of easy-to-install equipment l Machinery is less bulky than conventional rotomoulding machinery l Does not rely on electricity from a grid and is therefore apt for areas with irregular supply of electricity l Installation and maintenance are simple

SRM vs RM Solar Rotational Moulding 299%

Flat or sloped unimproved terrain

Internal rate of return

Site requirements

185%

transmission lines. A 1 sq m heliostat can deliver approximately 1,000 watts of energy to a target. Multiple heliostats combine to form a powerful heat source, which can be moved from target to target. The heat source can also be used for many applications in sustainable manufacturing or residential day lighting or facility heating. The ability to move the heat source allows for a simplified machine design and much lower purchase costs. Although a typical SRM system costs anywhere between $ 50,000 and $ 150,000, the return on investment is also high at 15%. No grid-tie is needed, and the one-time investment is only for the purchase of the heliostat array. In addition, the compact system can be set up quickly at a site with flat or sloped unimproved terrain. The energy cost of the finished product is virtually nil.

No – one time investment in heliostat array

60’ x 60’ & up

Grid-tie needed

Sensitivity to energy costs

System size

Yes – cost & Industrial profitability Yes – gas and building with directly linked electric concrete pad to energy costs

Varies, 45’ x 45’ to much larger

Environmental benefits of SRM l Mostly relies on the heat from the sun l Zero emissions l Dependence on power from oil is limited l Eliminates the use of fossil fuels l Heliostats can be made to be highly efficient (up to 75%) l Enables rotational moulding of oil-based polymers and biopolymers

Say Yes to SRM Zero emissions Quick set-up?

Rotational Moulding

Compact system

þ þ þ

Conclusion Harvesting freely available sunlight accompanied by low-cost hardware is the main benefit of this technology. The need of doing away with a building may seem far-fetched at this point, but SRM could pave the way of putting barren land to good use.

Solution provider LightManufacturing LLC, USA

Wood plastic composites

Working

together

one! AS

Wood Plastic Composites (WPCs) are produced by thoroughly mixing ground wood particles and heated thermoplastic resin. Although relatively new in comparison to the long history of natural lumber as a building material, WPCs can be used for railings, fences, landscaping timbers, cladding and siding, park benches, moulding and trim, window and door frames and indoor furniture.

PCs are composite materials made of wood fibre/flour and plastics. In addition to wood fibre and plastic, WPCs can contain other ligno-cellulosic and/or inorganic filler materials. WPCs are a subset of a larger category of materials called natural fibre plastic composites, which may contain no cellulose-based fibre fillers such as pulp fibres, peanut hulls, bamboo, straw etc. The most common method of production is to extrude the material into the desired shape, though injection moulding is also used. WPCs may be produced from either virgin or recycled thermoplastics including high-density polyethylene, low-density polyethylene, polyvinyl chloride, polypropylene, acrylonitrile butadiene styrene,

polystyrene and polylactic acid. Polyethylene-based WPCs are by far the most common. Additives such as colorants, coupling agents, ultraviolet stabilisers, blowing agents, foaming agents and lubricants help tailor the end product to the target area of application. Extruded WPCs are formed into both solid and hollow profiles. Various injection moulded parts are also produced, from automotive door panels to cell phone covers. In some manufacturing facilities, the constituents are combined and processed in a pelletising extruder, which produces pellets of the new material. The pellets are then re-melted and formed into the final shape. Other manufacturers complete the finished part in a single step of mixing and extrusion.

Features of WPCs l Do not corrode l Highly resistant to rot, decay and marine borer attack l Good workability and can be shaped using conventional woodworking tools l Often considered a sustainable material because they can be made using recycled plastics and the waste products of the wood industry Although these materials continue the lifespan of used and discarded materials and have their own considerable half life, the polymers and adhesives added make WPC difficult to recycle again after use. They can however be recycled easily in a new WPC similar to concrete.

In comparison with wood, WPC has the ability to be moulded to meet almost any desired shape.

WPC can be bent and fixed to form strong arching curves.

WPCs are manufactured in a variety of colours but are widely available in greys and earth tones. Advantage of WPC over wood Resistant to rot and does not need to be painted

Applications Dollplast Group of Companies Dollplast has over three decades of experience in producing plastics processing and recycling machinery. The company has been exporting recycling machinery across the globe. Recently, it has developed a WPC called Plastwud. Plastwud contains wood, plastic waste and additives. Features of Plastwud l Good stiffness and impact resistance l Good dimensional stability l Good chemical resistance and thermal properties l Excellent resistance to rot l Resistant to borer, moisture and warping l Manufactured using plastic waste that would be dumped in landfills or incinerated l Is recyclable l Has a long lifecycle Similar to wood, Plastwud has been processed to make furniture through sawing, drilling and gluing. It can therefore be used outdoors for garden benches and outdoor furniture and decking. Plastwud is made from plastic waste. One way in which waste plastics can be obtained is through processing material in the Dollplast Paper Plastic Separator. Arboform liquid wood Scientists from Fraunhofer Institute for Chemical Technology,

Germany, have developed a substance that could replace plastic: Arboform â&#x20AC;&#x201C; basically, liquid wood. Features of Arboform l Derived from wood pulp-based lignin, which is an abundant renewable resource, non-toxic and biodegradable l Can be mixed with other materials to create a strong, non-toxic alternative to petroleum-based plastics l Not made from felling of trees l Manufactured from the waste products of the paper industry l Eco-friendly alternative to plastic l Can be manufactured on a mass scale as well as moulded into any shape or form l Can be remoulded, reshaped and recycled on heating or cooling it several times l Disposed off in the same manner as wood either through incineration or decomposition When compared with wood and plastics, Arboform has better thermal and mechanical properties than wood and plastic put together. Without splitting at right angles when subjected to strain, this biodegradable thermoplastic engineering material is of superior quality and strength. Arboform can meet the technological demands, replacing the indomitable market giant â&#x20AC;&#x201C; plastic. It does not require any elaborate process to change its chemical composition before disposal and can be discarded off like wood.

Conclusion Due to the incorporation of recycled plastics and waste products of the wood industry, the popularity of WPCs is growing. Being highly resistant to rot and decay, WPCs have good workability and can be shaped using conventional woodworking tools. WPCs can also be recycled easily in a new wood-plastic composite, much like concrete. An essential advantage over wood is the ability of the material to be moulded to meet almost any desired shape.

Creating Zero liquid discharge technology

Could you imagine a process where virtually every litre of wastewater is recycled and reused completely? Such a process would effortlessly allow manufacturing companies to comply with wastewater disposal regulations. Zero Liquid Discharge (ZLD) is a process that completely eliminates liquid discharge from a system and recycles wastewater, which can be pumped back into the system.

Why explore ZLD? It complies with ever-tightening wastewater disposal regulations.

Although developed in the West, ZLD technology is being adopted widely in drought-stricken regions and pollution-sensitive environments.

well-designed ZLD system minimises the volume of wastewater that requires treatment, processes wastewater in an economically feasible manner and produces a clean stream suitable for reuse elsewhere in the facility. In simple words, ZLD is something that every company aspires to accomplish. Describing about the fundamental process, the ZLD system removes dissolved solids from wastewater and returns distilled water to the process (source). Reverse osmosis (membrane filtration) may be used to concentrate a portion of the waste stream and return the clean permeate to the process. In this case, a much smaller volume (the reject) will require evaporation, thus enhancing performance and reducing power consumption. In many cases, falling film evaporation is used to further concentrate the brine prior to crystallisation. Falling film evaporation is an energy-efficient method of evaporation, typically to concentrate the water up to the initial crystallisation point. The resultant brine then enters a

forced-circulation crystalliser, where the water concentrates beyond the solubility of the contaminants and crystals are formed. The crystal-laden brine is dewatered in a filter press or centrifuged, and the filtrate or centrate (â&#x20AC;&#x2DC;mother liquorâ&#x20AC;&#x2122;) is returned to the crystalliser. The collected condensate from the membranes, falling film evaporator and forced-circulation crystalliser is returned to the process, eliminating the discharge of liquids. If any organics are present, condensate polishing may be required for final cleanup prior to reuse. ZLD technology includes pretreatment and evaporation of the industrial effluent until the dissolved solids precipitate as crystals. These crystals are removed and dewatered. The water vapour from evaporation is condensed and returned to the process. This process may utilise all or some of the engineering modules including pre-treatment, membrane filtration, evaporation, crystallisation and solids recovery. Each module can be executed in parallel to expedite the design and implementation process.

Why ZLD? Interest in ZLD technology has grown in the industrial manufacturing sector over the past decade. Companies may begin to explore ZLD because of l Ever-tightening wastewater disposal regulations l Company mandated green initiatives l Public perception of industrial impact on the environment l Concern over the quality and quantity of water supply

The process ZLD technology includes pre-treatment and evaporation of the industrial effluent until the dissolved solids precipitate as crystals.

Suitability ZLD technology is particularly appropriate in water-short areas.

Environmental benefits ZLD systems provide numerous economic and environmental advantages for plant managers. Water is recycled and reused, saving on the cost and treatment of raw water. Since all water is reclaimed, no effluent is discharged from the plant, avoiding the cost of environmental impact. The technology is particularly appropriate in water-short areas.

Application Chemplast Sanmar Ltd Chemplast Sanmar Ltd has installed ZLD facilities at their Mettur plant at an initial investment of ` 27 crore. In fact, the Sanmar Group has installed ZLD facilities at their Cuddalore and Karaikal units at inception. All three units recycle and reuse effluents 100%. The ZLD facility ensures that no treated effluent from the plant is discharged into the environment. In September 2009, Chemplast Sanmar became the first chemical manufacturer to achieve 100% ZLD. Chemplast has been recognised for its contribution towards sustaining the environment by the Confederation of Indian Industry (CII). In December 2010, the company was awarded the 7th National Award for Excellence in Water Management by CII.

Conclusion ZLD is a process that is beneficial to the environment as well as municipal organisations. Through ZLD, precious monetary resources can be saved without any effluent or discharge. By employing some of the most advanced systems to treat, purify and recycle wastewater, ZLDâ&#x20AC;&#x2122;s economic and environmental advantages are translating into better returns for companies.

Sweet

Sugarcane-derived plastics

source of

packaging material

As environmental regulations become more stringent, manufacturers have begun to undertake drastic measures to control the overall impact their products have on the environment. This is restricted to not only the product itself but also all the manufacturing processes associated with developing the product. Through lifecycle assessments, researchers have often found that the packaging of the product has a more severe ecological impact than the product itself. This has prompted several companies to look at ways of developing environment-friendly packaging. One such instance is sugarcane-derived packaging.

sugarcane-derived plastic is a significant development in sustainable packaging. It is made from renewable resources unlike conventional plastics that are made from nonrenewable resources such as petroleum. Polyethylene (PE) derived from sugarcane has been assessed and has been found to emit up to 75% less greenhouse gases during its life span in comparison to conventionally produced plastic packaging. The new material is made through an innovative process that transforms sugarcane

into high-density PE plastic, a type commonly used for product packaging. PE employs ethylene as a monomer, the polymerisation of which produces various grades based on density and branching. The fabrication of this polymer requires ethylene, which is in turn derived from ethanol. Ethanol can be manufactured by conventional sources such as fossil fuel, corn or cellulose. Synthetic ethanol comes from fossil raw materials, and bio-ethanol comes from contemporary materials such as biomass.

Given below is an outline of the process involved in producing ethanol from sugarcane.

Sugarcane

Ethanol

Ethylene

Sugarcane to Ethanol The process has the following steps: a. Fermentation b. Distillation c. Stripping d. Dehydration e. Ethylene f. Polymerisation

150 gm sugarcane + 250 ml water

Boil

Add HCI to adjust pH (4-4.5)

Cool

Add yeast Saccharomyces cerevisiae

Incubate for 40 hrs @ 50oC

99.6% conversion PE

Ethylene

12.29 g of ethanol obtained

A schematic illustration of conversion of molasses to PE

PE derived from sugarcane has been found to emit up to 75% less greenhouse gases during its life span in comparison to conventionally produced plastic packaging.

India is an agricultural nation; there is an abundance of feedstock available for the development and manufacture of biopolymers.

PE derived from sugarcane replaces about 30% or more of the petroleum that would otherwise be used to manufacture generic plastics.

Sugarcane-derived polymers require less energy to process.

Challenges As India is an agricultural nation, there is an abundance of feedstock available for the development and manufacture of biopolymers. Although opportunities exist, there are challenges that sustainable packaging is fraught with. For instance, a majority of Indian companies are yet to develop in-house technologies for manufacturing bioplastics. The companies operating in the Indian market import their raw materials from the EU. Due to this, bioplastics cannot be price-competitive, and hence, there is a need to develop technological expertise to produce biopolymers in India. Also, India does not have stringent government regulations on the consumption of petroleum-based raw materials for packaging. In fact, bio-based packagers do not receive any tax incentives from the government in this respect.

Applications Braskem Braskem, a Brazilian plastics manufacturing company, was the first to come out with ‘green’ certified PE. Over the years, Braskem has been enlisted by companies around the world (eg Ecover in Belgium) for developing environmentally sustainable product packaging. Braskem produces the ‘green’ PE from sugarcane harvested in an efficient manner. Instead of using the traditional practice of cutting the sugarcane by hand and burning off the residue, a mechanical harvesting system has been introduced. This system enables leftover leaves and stalks to be collected and used for energy generation. Coca Cola and India Glycols Coca Cola has been marketing the bio-based PlantBottle PET bottles since 2009. The company has been sourcing the raw material from the Brazilian sugar industry for its global PlantBottle projects. The ethanol syrup is converted into glycol in a refinery process by India Glycols, Kashipur, in India, and then distributed to PET manufacturers in countries where PlantBottle programmes are underway. India Glycols offers bio-based polyols derived from molasses via ethanol. The 30% that the sugarbased glycol constitutes of the final material replaces the equivalent amount of monoethylene glycol, which has been used in PET material until now. The remaining 70% of the material is terephthalic acid.

Advantages of sugarcane-derived polymers over petroleum-based polymers Recyclable and environment-friendly to manufacture Require less energy to process

Manufacturing process

Result in few emissions Reduce dependence on crude oil and natural gas

ASUO2

O2/N2/Ar Bio-Glycols

Molasses

Distillery

Bio-Ethanol

Ethylene

ENA Liquor

Performance Chemicals

Bio-Ethylene oxide Bio-EIDs

Food Grade CO2 Graphical representation of India Glycols’ business

Conclusion With fluctuating oil prices and concerns about greenhouse gas emissions, the plastics industry is exploring renewable feedstock alternatives. In recent years, sugarcane ethanol has emerged as an important substitute for petroleum in the production of plastics. Having the same physical and chemical properties as regular plastics, this bioplastic, if leveraged correctly, could be the game changer for this industry.

Recycling polystyrene

Producing

eCO-friendly

blocks Polystyrene holds DVDs, cups hot brimming tea, secures packaging and insulates your home; although applauded universally, polystyreneâ&#x20AC;&#x2122;s omnipresent nature has now begun to raise concerns regarding its efficient disposal. Recycling polystyrene has not been met with much fervour due to the lack of incentive to invest in the required compactors and logistical systems. In such circumstances, what are the possible solutions?

olystyrene or styrofoam is an excellent packaging material because of its insulating and protective properties. Unfortunately, after the product is delivered and opened, polystyrene becomes a waste material. It is estimated that thousands of tonne of polystyrene are sent to landfills on an annual basis. Polystyrene is large and bulky with extremely low weight, and it is not hard to imagine the volumes of waste polystyrene could occupy in landfills.

Due to the low density of polystyrene foam, it is not economical to collect it.

Since 1990, no chlorofluorocarbons are used in the manufacture of polystyrene foam packaging products in the US.

An initial compaction process radically changes the density of the material and makes it a recyclable commodity of high value.

Polystyrene recycling machines form a dense block of material that is easy to handle.

Polystyrene recycling machines Polystyrene recycling machines essentially melt polystyrene (styrofoam) to form a dense block of material. The densified blocks are l Reduced by over 95% of the original material l Approximately 90 cm × 25 cm × 5 cm (from 2 cubic metre load of polystyrene) l Sterile l Easy to handle l Can be stored indefinitely l Turned into fuels (eg diesel) or products (eg garden furniture)

Several loads can be put through the machine over time until sufficient quantities have been produced for either sale or disposal. There is an emerging market for blocks for incineration, recycling and for the production of fuels. The latest polystyrene recycling machines are safe, simple and economical solutions to recycle polystyrene (styrofoam) waste to achieve large savings in transport and waste disposal costs. For instance, Styromelt is specially designed for applications where traditional hydraulic compaction is not economical, practical or where lingering odours and contaminants are present. The thermal compaction process can achieve a volumetric reduction of waste by up to 95% to dramatically reduce waste storage and traffic.

Market applications

Further benefits l Processed blocks are recyclable as product or fuel and can actually be sold to recyclers l Greater compaction rate – up to 10 times greater than hydraulic compaction l In-situ sterilisation of plastic material means the product can be stored indefinitely l Ability to deal with contaminants (eg blood, organic matter, metal, stone and glass) without damage or failure l Thermal compaction is a batch process and incurs no energy costs until the machine is full; the machine could be described as an ‘electric skip’

Disposing of polystyrene has the following drawbacks: 1. Boxes and packaging can take up large volumes of storage space prior to removal 2. Fish/meat packaging is contaminated with blood/fluids and can be a health hazard and attract vermin when in storage prior to removal 3. Running costs of disposal trucks are high 4. Because boxes and packaging take up a lot of space, transport lorries are filled quickly 5. Landfill disposal is expensive and bad for the environment

Environmental benefits l Recycling polystyrene would mean less dumping into landfills and thus less soil pollution, ie a chance towards clean disposal l Reduction in energy and fuel consumption during transportation of waste polystyrene to landfills l Production of recycled polystyrene that can be reused in a number of applications in a safe manner

l Local authorities l Fisheries industry l Retail l Sports stadiums l Fast food industry l Recycling industry l Cruise/ferry industry l Smoke houses l Hospitals l Arenas l Electronics companies l Waste management

Application Styromelt Ltd, UK l Machinery can be operated with few skills l Machinery occupies a small footprint, ideally suited for retrofitting in supermarket or municipal areas l The machine is weather proofed for outside use l Process is virtually silent running

Conclusion The introduction of polystyrene recycling machines will have positive cost cutting and environmental benefits. The installation of machines in public areas will help bring about awareness regarding this issue. Moreover, the machine’s ability to deal with contaminants is a feature that will definitely help change the way polystyrene is recycled.

Leading the Waste plastics in cement concrete

way

Continuous growth in population and the rapid advancement of developing countries have put enormous pressure on the planetâ&#x20AC;&#x2122;s natural resources. One area of immense concern is waste disposal. The unmitigated growth of non-decaying waste combined with increased consumerism makes it imperative for society, industries and governments to make end-of-life measures part of the product life cycle. One way of dealing with this is to mix waste plastics with cement concrete in the laying of roads.

lot of research and development in the area of recycling and disposal of plastics is currently being undertaken by not just industry but also government organisations. Waste plastics, it has been noted, have huge potential in construction and cement technology. With increase in vehicular volumes, the requirement of roads and pavements has also increased. This has in turn led to greater research in the area of road construction. Studies show that using plastic waste in cement concrete for pavements makes them less susceptible to rutting, fatigue or thermal cracking and low stripping due to moisture. Waste plastics offer greater durability and have low processing costs.

Advantages of using waste plastics as concrete modifier Easily binds to coarse aggregates at medium temperature Does not require any change in road laying practice Material is available locally in the form of shredded plastic being treated as waste The process of incorporating waste plastic modifiers in concrete is fairly easy. Coarse aggregates are heated to about 800Â°C. The waste plastics in powder form are then thoroughly mixed with the coarse aggregate mixture. This mixture is then allowed to cool down for 3â&#x20AC;&#x201C;4 hours and subsequently mixed with the fine aggregates, water and cement to form concrete.

Maintenance cost of plastic roads is almost nil.

Plastic roads have no seepage of water.

Polymer-bituminous-modified mix test performance When tested, this modified mix showed improved properties. The performance of the plastic– bituminous mix was judged on the basis of tensile and rutting tests. Indirect tensile test Tensile testing, also known as tension testing, is a fundamental materials science test in which a sample is subjected to uniaxial tension until failure. The results from the test are commonly used to select a material for an application, for quality control and to predict how a material will react under other types of forces. Properties that are directly measured via a tensile test are ultimate tensile strength, maximum elongation and reduction in area. From these measurements, the following properties can also be determined: Young’s modulus, Poisson’s ratio, yield strength and strain-hardening characteristics. Rutting test Wheel tracking is used to assess the resistance to rutting of asphalt materials under conditions that simulate the effect of traffic. A loaded wheel tracks a sample under specified conditions of speed and temperature while the development of the rut is monitored continuously during the test. The rut resistance can be quantified as the rate of rutting during the test or the rut depth at the conclusion of the test. There are no traces of stripping even after 20,000 cycles, and no pothole formation, rutting or ravelling have been observed after 5 to 6 years after construction.

9.0

6.8

Conventional mix Modified mix kg/sq cm

17554

20000

What makes concrete? The cement and water form a paste that coats the aggregate and sand in the mix. The paste hardens and binds the aggregates and sand together. In addition to the above components, concrete modifiers can be mixed for improving tensile and durability properties of the concrete. Modifiers are generally polymeric materials. Studies are being carried out to see how waste plastics as modifiers can further improve the properties of concrete.

Application

15000

10000

8650

5000

Conventional mix Modified mix Number of repetitions

Environmental benefits

Each 5-member family’s use of 5 g plastic bags a week across India would mean the use of 52,000 tonne of plastics every year. India spends about ` 35,000 crore every year on road construction and repair, and ` 100,000 crore a year only on maintenance. Roads lasting 2–3 times as long as conventional roads will result in savings to the tune of ` 33,000 crore a year in repairs, plus reduced vehicle wear and tear. In addition, 8% by weight of plastic waste in bitumen is equal to a saving of 0.4% of bitumen by weight in roads.

Plastic roads have better binding properties.

The Indian construction segment is a large industry and continues to show an upward trend with the potential of using waste plastics too. Apart from addressing the mounting problems owing to disposal, other reasons to promote the reuse and recycling of plastics are 1. Reduced extraction of raw material 2. Reduced energy consumption due to transportation 3. Easy implementation and greater profits

In India, the Bengaluru municipality has taken steps to incorporate waste plastics in the construction of roads. A new blower developed by KK Waste Management and under patent in Bengaluru introduces waste plastics uniformly into Hot-Mix plants. Polymer-modified bitumen has been in use for a long time. It has been approved in the Indian Roads Congress’ Special Publication 53 guidelines, 1999. The best results are found to be with 8% waste by weight in 80/100 grade bitumen. The result of using polymer-modified bitumen was reduced road cracking after 1 year on the Bengaluru–Mysore State Highway versus an unmodified road. Other roads that have been constructed using waste plastics are Shankar Mutt Road, K H Road, M G Road (towards Trinity Circle), J C Nagar Road and Millers’ Road in Bengaluru.

Say Yes to plastic roads Marshall stability value High tensile strength Better durability

þ þ þ

Conclusion The use of waste plastics in concrete is a simple process that requires no new machinery. Using plastic modifiers, the strength of concrete can be increased. Thus, the use of waste plastics can help reduce the quantity of concrete used during construction. This not only saves material but also fuel, energy and costs. The modified cement concrete mix also helps avoid energy intensive processes, such as incineration, that may be required for plastics recycling.

Delamination of laminated packaging

cleaner disposal process Laminated packaging is a widely used packaging material with applications in a range of food and non-food products. Laminates of plastic and aluminium are commonly used for applications such as pet food, drink pouches, toothpaste tubes and cosmetics. Till recently, there was no technology in place that could recycle laminated packaging, but that has now changed. A process that is technologically and environmentally sound is slowly shaping up.

aminate aluminium foil packaging with plastics has many applications. Such type of packaging can be used with plastic either on one side or on both sides for medicinal strips, toiletries and processed foods. However, the entire packaging process generates a high volume of refuse at almost every stage of production. The chief components of the refuse are thin foils of aluminium and plastics. These are non-recyclable. Incineration and landfilling are expensive methods of disposal, and it has been estimated that the possible recovery of such type of packaging refuse in India would result in monetary savings to the tune of ` 63 million per year.

Delamination technology can be easily carried out at ambient temperature.

Recovery of lamination packaging refuse could result in monetary savings to the tune of ` 63 million per year.

Recycling of laminated packaging The entire refuse can be in the form of sheets, strips, tubes or sometimes in an already shredded form. The first step of the recycling process of laminated packaging involves the shredding of the refuse in strips of equal width. These are then dipped into inorganic solvent, 50–70% nitric acid at ambient temperature. The mass is allowed to stand in the acid for 4–7 hours, ie till delamination is complete. At ambient temperature and 50–70% concentrated nitric acid, the binder adhesive from the lamination dissolves while neither aluminium nor plastics dissolve. The aluminium foil eventually gets fully separated from the plastic, and the constituents remain in a floating/

submerged condition depending on their individual specific gravities. The delaminated constituents are removed from the nitric acid and submerged in a series of baths. First is a fast bath of lime water, followed by one or more baths of water. This enables separation and sorting of the constituents. Fragments of separated plastics and aluminium foils are centrifuged to dryness before a total sun bath for complete dryness. The separated fragments of aluminium foil are now ready for producing aluminium ingots, while the plastic fragments are ready for producing recycled plastic granules.

Application Triplex Inventives Triplex Inventives saw the potential of great economic and ecological benefit and developed a process whereby delamination of laminated packaging refuse through the use of acetone– water could separate the constituents of the waste matter effectively. The technology was a recipient of the Plasticon Award 2009 for Innovation in Recycling Technology. This manufacturing process was developed and patented by Ashutosh Mukhopadhyay of Triplex Inventives.

Advantages of delamination technology Easily carried out at ambient temperature

Disadvantages of delamination technology

Overall production costs are low Difficult to implement on a large scale Produces material that can be subsequently sold for a profit Costly because it is a manual process Utilises inorganic solvents to provide an eco-friendly and effective waste treatment process

Conclusion With the growing preference for lightweight product packaging, the enhanced usage of laminated films compels the industry to find greener recycling solutions. After reviewing the technical, commercial and environmental performances of the delamination process, its suitability for the packaging industry can be evaluated.

Waste plastics in cement kilns

Fuelling energy-intensive industry

Extremely thin plastics are extremely difficult to recycle. This makes their disposal challenging as thin plastic bags can get carried to far-flung areas by wind resulting in soil and water contamination. These thin plastics can be collected and used as fuel and supplementary raw material for cement kilns, thus resulting in their disposal before they cause damage to the environment.

ne of the most-consumed material in our society is cement. The disposal of plastic waste in cement kilns is not only recycling but also another form of end-of-life disposal and an alternative to landfilling. Used polymers such as used tires and rubber wastes, dewatered and treated sewage pellets, hydrocarbon waste (eg oil), contaminated general waste, biomass and finally plastics can be used as secondary fuels in cement kilns. Co-processing Co-processing is the use of waste as raw material or a source of energy or both to replace natural mineral resources and fossil fuels such as coal, petroleum and gas (energy recovery) in industrial processes, mainly in energy-intensive industries such as cement, lime, steel, glass and power generation. Waste materials used for co-processing are referred to as alternative fuels and raw materials.

Co-processing is a proven sustainable development concept that reduces: l Demands on natural resources l Pollution and landfill space l Environmental footprint The reason why co-processing is so relevant is simple. The global industrial demand for energy is roughly 45% of the total demand. Of the total global energy demand, the requirements of the energy-intensive industries are 27%. Worldwide, wastes suitable for co-processing have an energy potential of 20% of the fossil fuel energy. It is estimated that by 2030, the thermal substitution rate of waste could rise to nearly 30%. In the countries of Europe, the available energy potential in waste currently represents nearly 40% of this demand, and this is expected to rise to almost 50% by 2030. About 60% of the waste that could be used for co-processing is biomass and therefore carbon neutral.

Co-processing reduces environmental footprint.

Co-processing reduces pollution and landfill space.

Co-processing is a sustainable development concept that reduces demands on natural resources.

Environmental benefits 1. High-flame temperature (2,000째C) ensures complete destruction of harmful pollutants 2. Complete scrubbing of exhaust gas due to counter current flow of raw material, resulting in trapping of heavy metals, sulphur and other pollutants within clinker 3. High residence time >5 sec in oxygen-rich atmosphere ensures complete destruction of organic compounds found in any waste 4. Inclusion of ashes and residual metals from the wastes within the clinker crystal structure 5. Kiln lines equipped with ESP/bag filters ensures negligible particulate emission 6. Intense contact between solid and gas phases ensures condensation of volatiles, absorbs SO 2 and neutralises acid gases 7. Destruction and removal efficiency of 99%

There are two environmental aspects being addressed through the usage of plastics in the cement industry. These are contribution towards the manufacturing of cement itself and the development of a waste management system for plastic waste. In terms of the cement manufacturing process, the use of alternative fuels and raw materials has the potential to reduce emissions to the environment relative to the use of conventional fossil fuels and conserves non-renewable resources. In terms of the waste management system, cement kilns offer a safe alternative to conventional disposal of waste in dedicated waste incinerators or in landfills, again resulting in overall benefits by reducing environmental burdens and the need for dedicated treatment capacity. Co-processing of plastic waste in cement kilns is suitable for the following reasons:

Application ACC Kymore Cement Works explored the option of co-processing plastic waste in 2008. Over the three-day trial period, several plastics were co-processed. Some of these were polyethylene terephthalate, polypropylene, acrylonitrile butadiene styrene, nylon and polystyrene. ACC had carried out the prerequisite tests to determine co-processing feasibility. The results are illustrated in the graph.

Evaluation of the co-processing feasibility of plastic waste conducted by ACC

Parameter

Units

Dioxin & ng TEQ/Nm3 Furan TOC mgC/Nm3 HCl mg/Nm3 HF mg/Nm3 SO2 mg/Nm3 SPM mg/Nm3 CO mg/Nm3 NOx mg/Nm3 Mercury mg/Nm3 Metals (except mg/Nm3 Cd & Tl) Cd & Tl mg/Nm3

Norm 0.1

Measured stack emission during the trial Before CoAfter co-processing processing co-processing 0.004 0.0033 0.0029

20 50 4 200 50 100 400 0.05 0.5

5.5 ND ND 77 44.9 446 651 0.014 0.047

7.36 ND ND 27.75 48.6 780 600.5 0.046 0.041

6.01 ND ND 12 48.9 313 614 0.006 0.037

0.05

0.002

0.004

Conclusion Economic growth coupled with changing consumption and production patterns is resulting in rapid increase in generation of waste plastics. By putting in place regulations for cement makers to use wastes that can burn, such as plastic wastes and tyre chips, as alternative fuel in cement kilns will prove to be helpful. This can result in reducing greenhouse gas emissions and avoid creation of landfills.

A silent journey Waste plastics in railway sleepers

A railway sleeper is a rectangular support for the rails in railway tracks. Sleepers transfer loads to the track ballast and subgrade, hold the rails upright and keep them spaced to the correct gauge. Railway sleepers were traditionally made of wood, but pre-stressed concrete is now widely used, especially in Europe and Asia. In the midst of burgeoning transport systems, an innovative application of waste plastics in railway sleepers is being explored.

of January 2008, the approximate market share in North America for traditional and wood sleepers was 91.5%, the remainder being concrete, steel, azobĂŠ (red ironwood) and plastic composite. Although far less than wood or concrete, the advent of plastic composite sleepers has made noticeable changes. To address the issue of disposal of waste plastics, research is being conducted to promote the use of plastic waste in the construction of railway sleepers. Successful use of waste plastics in railway sleepers has the potential of l Increasing the life span of railway sleepers by preventing cracking l Reducing noise through damping l Addressing end-of-life options for waste plastics Polymeric composites can be formed into articles of construction to replace similar articles made of wood and concrete.

Composite sleepers are resistant to insect and moisture damage.

Equipment used to install wood and concrete sleepers can be used to install composite sleepers as well.

Composite sleepers are electrically non-conductive.

Composites comprise l Polymer component of polyolefins – preferably obtained as waste or recycled waste l Rubbery polymeric component – preferably obtained from disposed tires l Reinforcing filler component comprising mica – mica preferably of the expanded variety to allow for a reduction in density over similar composites containing traditional mica Evaporation of volatile compounds initially contained within the different components, primarily the rubbery polymeric component, allows for the production of articles of construction having a foamed inner core, in which the foamed cell structure has not been achieved through the use of traditional CO2-generating foam agents.

Composite sleepers are resistant to chemical damage.

Composition of the composite

Polymer component Polymer component is 40–70% polymeric composite – waste or recycled polyolefins; the polyolefins are selected from the group consisting of high-density polyethylene, low-density polyethylene, linear low-density polyethylene, propylene homopolymer, propylene–ethylene copolymer and combinations of these polymers. The polymer component further comprises a stryrenic polymer component. Rubbery polymeric component Crumbed tire fragments and 4–40% of the polymeric composite

Wooden railway sleeper versus composite railway sleeper

Reinforcing filler component Expanded mica and glass fibre and 6–50% of the polymeric composite

Applications

Environmental benefits Advantages of using composite railway sleepers Greater strength Better thermal coefficient of expansion Completely recyclable material Use of waste resources Longer life span than conventional wood sleepers Waste plastics used in the composite material helps in damping vibrations and is superior to conventional wood sleepers

Tietek Inc Tietek Inc, a subsidiary of North American Technology Group Inc, initiated the development of composite railway sleepers in 1993. The railway sleepers were tested at Transportation Technology Center Inc, a subsidiary of the American Association of Railroads in Pueblo, Colorado, and obtained the approval after seeking a load of greater than 400 gross million tonne in use on different tracks. Patil Group of Industries In India, this technology has been implemented by the Patil Group of Industries. They have supplied over 11 million composite railway sleepers to Indian Railways and other industrial giants. In fact, they have been instrumental in the completion of the 760-km-long Mumbai–Goa Konkan Railway project by supplying more than 9 lakh composite railway sleepers within 24 months.

Conclusion Other than being environmentally responsible, composite sleepers are superior in performance and provide significant value to customers. By using these sleepers, railroads can augment the profitability of operations by minimising maintenance costs, reducing downtime and improving performance. Proven to be viable replacements for traditional wood sleepers, this ingenious application of waste plastics is also doing its bit for the environment.

Clean Zero pellet loss

sweep! Over the past few years, researchers have reported deaths and noted poorer health of more marine life. One of the reasons behind the decline in the health of marine life lies in careless disposal of plastic products such as bags, bottles, caps etc. Since minimising the danger of plastic dust escaping into the environment during machining is easily said than done, Operation Clean Sweep (OCS) is a new technique that is helping processors counter attack this issue.

To minimise plastic litter, the pelletising machine must have sharp blades.

Discarded or lost fishing gear is one of the biggest contributors to marine litter.

The zero pellet loss initiative helps manufacturers adhere to environmental regulations while minimising wastage and subsequent costs.

OCS can be implemented by using proper containment procedures during transportation.

lastic litter caused by accidents and spills during manufacturing and careless disposal has entered streams and other water bodies. When these pellets are ingested by wildlife, they are not digested and result in malnutrition and starvation of the animal. To minimise the damage which has resulted in polluting the natural heritage coupled with threatening the existence of animal life, a solution is being fine-tuned. Operation Clean Sweep (OCS) To curb pollution of the environment due to plastics, plastics associations of developed countries such as the US, UK and Canada have initiated the OCS programme. This initiative has been in practice

OCS can be implemented through a few basic measures: l Introducing slopes and berms that will collect plastic pellets l Keeping vacuums and brooms handy for personnel to sweep up any wastes l Providing screens and meshes over drains l Installing valves on site l Using proper containment procedures while transportation l Attaching collection containers on machines

Further, to minimise the danger of plastic dust escaping into the environment during machining: l Keep the machines in good order l The pelletising machine must have well-sharpened blades l Proper-sized granulators must be used l Waste disposal containers must be placed strategically l Conveying systems must be installed to avoid collisions of material with hard surfaces

in the developed world for about 12 years. In the US, it has been undertaken by the Society of Plastics Industry (SPI) and the American Chemistry Council (ACC) to promote sustainability of plastics through cleaner disposal methods. The Canadian Plastics Industry Association (CPIA) and the British Plastics Federation (BPF) have also developed detailed guidelines and manuals for plastics manufacturers to help them implement zero pellet loss. Through OCS, plastics manufacturers are educated on the benefits of upgrading their production sites and machinery as well as training their personnel in the concept of zero pellet loss. The aim of OCS is to contain, reclaim and properly dispose plastic resins.

Environmental benefits The zero pellet loss initiative helps manufacturers adhere to environmental regulations while minimising wastage and subsequent costs. More importantly, it ensures that indiscriminate and careless disposal of plastics that can pollute soil and water bodies is avoided through simple and inexpensive steps such as equipment and technology upgradation, education and personnel training.

Implementation The All India Plastics Manufacturersâ&#x20AC;&#x2122; Association (AIPMA) has signed a MoU with SPI, USA. This MoU was signed in March 2012 to promote not only greater trade between the two countries but also implement a systematic process akin OCS in India.

Conclusion By increasing the efficiency of pelletising machines, companies will be able to use more material in their product manufacture resulting in lesser wastage. In the process, companies will be able to enhance their reputation in the fraternity and egg others on to practice similar techniques. By keeping plastic pellets out of the environment, the plastics industry can drastically reduce its environmental footprint.

Energy Constraint-based planning and scheduling

consumption optimisation

Although energy-saving practices are widely implemented by plastics manufacturers, there remains more potential to reduce energy consumption through technological innovation and research and development. Moreover, the recent economic climate, ie volatile crude oil prices and more stringent environmental legislation, makes it essential for companies to continuously strive towards energy reduction. Many other industries facing similar challenges in energy conservation have turned to technologies that make them more efficient. However, generic industry solutions cannot be applied to the plastics sector. This industry needs tailor-made solutions that will reduce overall energy consumption during production.

ith the recent economic fluctuations, many practices for energy saving such as Enterprise Resource Planning (ERP) and Supply Chain Management (SCM) technologies have been adopted by other industry segments. Experts believe that improved planning and scheduling systems can make a significant difference to the plastics industry. Although optimisation in plastics manufacturing will require significant investments (initial and regular personnel training), several companies abroad, in particular those of the EU, have developed and marketed such software simulation packages. Constraint-based manufacturing Planning and scheduling solutions can help plastics manufacturers reduce energy consumption. Some of these solutions are Activity-based costing when planning Before reducing energy consumption, it is important to understand where, when, why and how much energy is used. Useful energy key performance indicators can be derived and then used to monitor and reduce further consumption of energy. A constraint-based system includes the ability to associate fixed and variable costs with various aspects of production planning, including materials, usage of different machine/mould combinations, performing changeovers and idle time. It therefore enables users to project the energy consumption of alternative production plans. Optimising machine routing and mould allocation decisions A large plastics manufacturer could have 50â&#x20AC;&#x201C;100 injection moulding machines at a given site. These may have several hundred moulds, with perhaps multiple copies of the more popular moulds, and usually any one mould can be fitted to multiple machines. Because several thousand items are made, the combinations of the problem can increase. There may also be practical considerations on the shop floor such as trying to achieve long production runs (to avoid unnecessary and costly

changeovers) that sometimes prevent the least cost machine/mould combination from being used. Considering all of the possible routing options and simultaneously creating a weekly master production plan for 6â&#x20AC;&#x201C;12 months, respecting the myriad constraints becomes impossible using conventional tools such as spreadsheets. Constraint-based systems are simultaneously able to consider all of the possible routing options, both in terms of machines and moulds, deriving a feasible plan in minimal time. Users can let the system manage the constraints and complex capacity/demand calculations, while they apply their considerable planning more effectively, focussing on comparison of different planning strategies and conducting what-if analysis to arrive at the most acceptable trade-off in terms of plant throughput, energy consumption, customer service and machine efficiency. Reducing mould changeovers and machine idling The main reason for machines becoming idle is when performing a mould changeover. A further undesirable consequence of changeovers and restarting machines is increased wastage of costly material. It therefore becomes necessary to plan changeovers in production schedules by l Identifying when machines may be idle for long periods of time to identify opportunities for energy reduction through stopping/ starting machines l If possible, idle time should be minimised by planning long production runs l Minimise the number of changeovers during planning/scheduling to reduce wasted energy and material A constraint-based system is able to represent all typical constraints associated with plastics manufacturing â&#x20AC;&#x201C; including mould changeovers. As a result, any derived plan is feasible and provides more accurate long-term visibility of projected times when specific machines may be idle. Management is therefore better informed in terms of introducing machinery shutdowns at appropriate times and so minimising related energy costs.

A constraint-based system has the ability to associate fixed and variable costs with various aspects of production planning.

Constraint-based systems are simultaneously able to consider all of the possible routing options, both in terms of machines and moulds, deriving a feasible plan in minimal time.

A constraint-based simulation system can allow planners to make informed decisions in their planning process from the point of inventory, throughput or material and energy conservation.

Improved visibility and control In a constraint-based application, long-term demand visibility and future inventory goals can be merged with complex machine/mould constraints. The ability to represent costs and compare plans from a broad range of perspectives (eg customer service, changeover frequency, cost, energy and production throughput) enables the planner to quickly and consistently identify optimal trade-offs between customer, energy and production conflicts. A planning and scheduling system can allow energy monitoring and control objectives to be embraced as an integral part of the planning process.

What-if analysis Plastics companies need to conduct what-if simulations for a variety of reasons. Spreadsheets can be extremely timeconsuming. A constraint-based simulation system can facilitate such strategic analysis. Alternative plans may be created by simply changing constraints/parameters in the model. This can allow planners to make informed decisions in their planning process from the point of inventory, throughput or material and energy conservation.

Environmental benefits l Reduction in overall energy consumption during manufacture l A constraint-based simulation program helps manufacturers anticipate energy consumption

Applications Dow Chemical Company Dow Chemical Company has implemented the use of the Logility Voyager Manufacturing Planning System (Logility Inc, UK). With significant changeover, production and additive constraints, The Dow Chemical Company needed to improve visibility across plants, reduce inventory, decrease the amount of off-grade product produced and increase efficiency. Through better inventory and raw material management, companies can save energy and optimise output. In the future, a module for especially monitoring energy consumption can be incorporated into a constraint-based software system. Bharti Telecom PPS and Nanyang Technological University, Singapore A study carried out by researchers from the Nanyang Techological University, Singapore, details the possible incorporation of simulation software for optimising manufacturing parameters on the shop floor of Bharti Telecom’s Plastic Processing Section. This particular unit that produces plastic components for the assembly of Bharti telephones has forty different plastic components that have one mould for each part. The production line also comprises seven IMMs, two ovens/pre-heaters, three presses, one granulator and one buffing machine. The aim of the simulation support system was to optimise production through meeting due dates, reduce flow time and WIP and maximise machine utilisation by, for instance, reducing idle running time. Although this is a theoretical case study, future work aims to run trials of these scheduling algorithms in conjunction with the plant’s ERP software. Sun Vacuum Formers and Auto Décor These manufacturers of plastic components and auto ancillaries use Eastern Software System (ESS) ERP systems to optimise their outputs and reduce overall wastage. IBM’s ILOG used by BASF Using IBM ILOG’s optimisation-based planning and scheduling solution, BASF, Germany, better aligned its plastics production with demand, while accomplishing planning tasks two to three times faster than the previous planning method.

Conclusion Plastics manufacturing environments are extremely complex and considerably flexible in nature. However, in these times, even a small increase in energy prices can have a dramatic impact on a company’s balance sheets. To survive, companies need to carefully investigate areas of cost savings. With timely planning and scheduling, companies with energy costs significantly in excess of industry averages will find the aforementioned technologies helpful to achieve savings.

Developing Use of rapid prototypes

component plastics

A decade ago, the vocation of mould-making was largely based on skilled istorically, prototyping of components often necessitated the manufacture experience and craftsmanship. The advent of steel moulds. This is both time consuming and costly. Further, design of technology has made mould-makers changes often meant that the initial prototype mould had to be extensively modified or scrapped. In recent years, the following technologies have efficient enough to cut down on time and cost. been developed to produce prototypes directly from computer designs, without However, in contrast to other industries, the the need for moulds: acceptance of technology in mould-designing for plastics has been relatively slow. Until only 1. Stereolithography quite recently, commercial software systems Stereolithography is an additive manufacturing process that employs a vat of liquid ultraviolet curable photopolymer ‘resin’ and an ultraviolet laser to build parts’ layers have begun to appear and are being one at a time. For each layer, the laser beam traces a cross-section of the part pattern adopted in the tool-making and on the surface of the liquid resin. Exposure to ultraviolet laser light cures and solidifies the moulding industry. pattern traced on the resin and joins it to the layer below. After the pattern has been traced,

the stereolithography’s elevator platform descends by a distance equal to the thickness of a single layer, typically 0.05–0.15 mm (0.002” to 0.006”). Then, a resin-filled blade sweeps across the cross section of the part, re-coating it with fresh material. On this new liquid surface, the subsequent layer pattern is traced, joining the previous layer. A complete 3D part is formed by this process. After being built, parts are immersed in a chemical bath to be cleaned of excess resin and are subsequently cured in an ultraviolet oven.

Stereolithography is an additive manufacturing process that employs a vat of liquid ultraviolet curable photopolymer ‘resin’ and an ultraviolet laser to build parts’ layers one at a time.

A rapidly growing application of Selective Laser Sintering (SLS) is in art.

2. Selective Laser Sintering (SLS) SLS is an additive manufacturing technique that uses a high power laser (eg a carbon dioxide laser) to fuse small particles of plastic, metal (direct metal laser sintering), ceramic or glass powders into a mass that has a desired 3D shape. The laser selectively fuses powdered material by scanning cross sections generated from a 3D digital description of the part (eg from a CAD file or scan data) on the surface of a powder bed. After each cross section is scanned, the powder bed is lowered by one layer thickness, a new layer of material is applied on top and the process is repeated until the part is completed. Because finished part density depends on peak laser power rather than laser duration, a SLS machine typically uses a pulsed laser. The SLS machine preheats the bulk powder material in the powder bed somewhat below its melting point to make it easier for the laser to raise the temperature of the selected regions the rest of the way to the melting point. SLS technology is in wide use around the world due to its ability to easily make complex geometries directly from digital CAD data. While it began as a way to build prototype parts early in the design cycle, it is increasingly being used in limited-run manufacturing to produce end-use parts. 3. Ballistic particle manufacturing Ballistic particle manufacturing uses CAD-generated 3D solid model data to direct streams of material (waxes, plastics, photo curable polymers, ceramics or metals) at a target, building 3D objects in much the same manner an ink-jet printer produces 2D images. An object is built by a three-axis robotic system controlling a piezoelectric ink-jet mechanism ”shooting” particles of the material, producing multiple cross sections, onto a target. There are different ink-jet techniques (deposition systems), but all rely on squirting a build material in a liquid or melted state that cools or otherwise hardens to form a solid on impact.

SLS is an additive manufacturing technique that uses a high power laser to fuse small particles of plastic, metal, ceramic or glass powders into a mass that has a desired 3D shape.

Building 3D objects in ballistic particle manufacturing uses CAD-generated 3D solid model data to direct streams of material at a target, building 3D objects in much the same manner an ink-jet printer produces 2D images.

Environmental benefits Rapid prototyping finds use and application in almost all the industries. The advantages of rapid prototyping include the following: l Visualisation capabilities are enhanced in the early designing phase l The user gets a fair idea of how the final product will look by observing the working model in the early design stage l Design flaws can be detected before the manufacture process is initiated l Enables producer and users to participate actively l The user is able to get a higher output l Development costs are reduced considerably and hence quite cost effective l Increases the speed of system development l Assists in refining the potential risks that are involved in the delivery l Different aspects of the prototype can be tried and tested and immediate feedback is possible from user l Better communication is enabled between the user and designer as there is clear expression of requirements and expectations from the start itself

Application XO Heart Shield One of the largest makers of protective athletic products wanted to expand into chest protection for young baseball players in the US. A flawless prototype for testing and tooling verification was critically important. The process of overmoulding – joining flexible and hard materials – added a layer of complexity to the task, which had to be completed in just one week. Cadability, Inc, provided data files to ART Corp Solution from which they produced a stereolithography master and rubber tooling. The experts cast a hard urethane liner and then overmoulded it with a soft rubber-like urethane. The unique design of the heart shield product channels impact energy to three anchor points, away from the critical heart area, greatly reducing injury potential. For testing purposes, the XO Heart Shield was glued onto T-shirts. During actual production, the device is injection moulded directly onto the T-shirt. A single iteration of the prototype proved highly effective and successful. The one-week turnaround enabled the client to prove the effectiveness of the design before making an enormous financial commitment to creating the product. Thus, rapid prototyping not only helped create a precise and successful product but also enabled its production in limited time.

Conclusion Generally, one or more prototypes are developed in the process of software development in a series of incremental and iterative steps. Every prototype that is manufactured is based on the performance of previous designs, and it is a corrective process through which defects or problems of the past design are corrected. The product is readied for production when the prototype is refined as per requirements and meets all the design goals such as manufacturability, robustness and functionality. Significant advantages of rapid prototyping include reduction in project cost and risk.

FACTS and

Figures A constraint-based simulation system can allow planners to make informed decisions in their planning process from the point of inventory, throughput and material and energy conservation.

The successful use of waste plastics in railway sleepers has the potential of increasing the life span of railway sleepers by preventing cracking, reducing noise through damping and addressing endof-life options for waste plastics.

Studies show that using plastic wastes in cement concrete for pavements makes them less susceptible to rutting, fatigue or thermal cracking and low stripping due to moisture.

The possible recovery of laminated packaging refuse could result in monetary savings to the tune of ` 63 million per year. Studies have proved that a variable frequency drive retrofit can save 20-50% of the power draw of most IMM hydraulic pump motors.

Polyethylene derived from sugarcane has been found to emit up to 75% less greenhouse gases during its life span in comparison to conventionally produced plastic packaging.

Runnerless moulds are more

advantageous than cold runner systems as they eliminate waste plastics completely.

After implementing the injection stretch blow moulding technology, Sidelâ&#x20AC;&#x2122;s NoBottle technology makes PET bottles that weigh a mere 9.9 g. Building 3D objects in ballistic particle manufacturing uses CAD-generated 3D solid model data to direct streams of material at a target, building 3D objects in much the same manner an ink-jet printer produces 2D images. Polystyrene recycling machines essentially melt polystyrene (styrofoam) to form a dense block of material that is sterile, easy to handle, can be stored indefinitely and/or turned into fuels (eg diesel) or products (eg garden furniture).

Polyethylene derived from sugarcane replaces about 30 percent or more of the petroleum that would otherwise be used to manufacture generic plastics.

Solar rotomoulding machinery, being less bulky than conventional machinery, does not rely on electricity from a grid and is therefore apt for areas with irregular supply of electricity.

By using thin plastics as supplementary raw material for cement kilns, one can reduce demands on natural resources, pollution and landfill space and environmental footprint. Co-injection moulding technology is

environment-friendly as it uses post consumer recycled material as core.

Co-injection technology allows processors to use the maximum amount of recycled material in product without compromising on quality.

Indian Foundry Sector

Indian

Foundry Sector

oundry is a well established and dynamic sector of the Indian economy. According to the recent World Census of Castings by Modern Castings, USA, India ranks as the second largest casting producer producing an estimated 7.44 Million MT of various grades of castings as per international standards. These include ferrous, non-ferrous, aluminium alloys, graded cast iron, ductile iron, steel, etc., for applications in automobiles, railways, pumps, compressors & valves, diesel engines, cement/electrical/textile machinery, aero & sanitary pipes & fittings, etc., and castings for special applications. Grey iron castings account for the major share of total castings produced. In fact, of the total casting produced, up to 70% are grey iron castings. In India, there are approximately 4,500 foundry units of which 80% can be classified as small scale units & 10% each as medium & large scale units. Approximately 500 units have international quality accreditation. Most large foundries are modern and globally competitive. They also work at nearly full capacity in order to keep up pace with high global and domestic demands. Over the last few years, the growing awareness pertaining to the environment has resulted in many foundries switching over to cleaner, energy-efficient technologies. The foundry sector, which in the past has conjured up images of poorly designed machinery, ill-efficient machinery and hazardous emissions, is slowly undergoing a transformation. With growing exposure to the importance of health and safety of personnel and the importance of reducing the negative impact on the environment, Indian foundries are investing in better equipment while also implementing best practices. The ‘green’ manufacturing technologies discussed in this compendium highlight how small changes can have a significant impact on reducing the carbon footprint of a given foundry. For instance, optimised cupolas and furnaces help increase melt efficiency, thereby saving tremendous amounts of energy, while the use of IT has made it possible to reduce material wastage. With increasing energy and raw material costs, it is vital that the Indian foundry sector embraces ‘green’ manufacturing technologies. With the production of castings increasing at the rate of approximately 15% every year, Indian foundries have the opportunity to expand their share in the export markets. To conclude, the implementation of modern technology and the adherence to environmental legislation will ensure that Indian foundries remain competitive in increasingly difficult economic climates.

We, the industry, specifically the manufacturing sector, need to engage and accept that we have a prime responsibility towards ensuring that the environment is not degraded for the future generations. There are many reasons for the primary ownership of this agenda to be with the industry. To start with, we are the ‘dream merchants’ who create aspirations/demand and thereafter, offer products and services for the society to consume. Hence, we have the responsibility of ensuring that the offerings are not putting extra pressure on the environment. To illustrate, we need to produce pumps that consume less electricity, engines that do not pollute or even, offer detergents/shampoos that consume less water. The industry is also the biggest investor, larger than the government; hence, the added compulsion that in creating assets/facilities, the environment is not degraded either through pollution or erosion of natural resources. The industry also claims to be ahead of everyone else (including the government and civic society) in terms of resources, technology and flexibility. Hence, they are best equipped to address environment issues. Society, in general, and industry, in particular, needs to adopt a more holistic approach towards ‘green’. Often, we think that conservation and avoiding abuse of nature is the limited role of the green agenda. But a truly green ecosystem ‘uses nature, in all aspects, while making sure that nature is not abused’ in the process. There is enormous energy and potential in Nature (wind, sun, water... Panchbhutas, as they are referred to). Rainwater harvesting, solar thermal, photovoltaic, natural ventilation, etc., are proven technologies, ready for application and with a very strong business case for green. The book deals at length with how the manufacturing processes should aspire conservation of water, energy and other natural resources. It also covers extensively how waste should be reduced and recycling should be given imputes— excellent coverage. I, however, strongly believe that the role of industry/ manufacturing with respect to Greenshoots is not limited to the manufacturing process or factory premise. A truly green organisation looks at the entire value chain. The organisation should consider green building to house their processes, give the highest priority to vendors who are green (use energy-efficient materials and processes), address product stewardship in terms of life cycle. E-waste and medical waste treatment is the biggest challenge beyond factory premises...but the problem generates from the factories. Hence, the industry should aspire the status of being a green company/business and not just limit itself to green building or green manufacturing. This, in my opinion, is a direction in which the industry should move for it to play a meaningful and responsible role in society.

Pradeep Bhargava Director, Cummins India Ltd.

Harsh K Jha President, Indian Institute of Foundrymen - Kolkata

From red to orange to green… …this is the chosen path for the foundry sector. Whether ferrous or non-ferrous, foundry is considered the mother sector, the very foundation of human and industrial development. Growth of the engineering business is critically dependent on the availability of castings—in all shapes and sizes—from massive windmill rotating blades or power plant equipment to miniature shapes required by orthodontics. It is a considered a ‘red’ industry based on the impact it has on the environment. The popular conception is that foundry poses a challenging environment—hot, humid & dusty; it is energy intensive and consumes non-renewable energy. The foundry sector has long recognised the need to become energy efficient and make its processes more eco-friendly. It is understood that some of the mitigation strategies it adopts may also contribute to it becoming more cost effective. But then, there are others which will call for examining them from a different lens of sustainability of business itself. In the mission to make the foundry processes environment friendly; the foundry equipment and chemical manufacturers and, most importantly, foundries themselves have a key role to play. Be it the choice of raw materials (use of energy-efficient pig iron); avoiding material loss (through near-net shape casting); improving productivity and minimising rejections (through automation), foundries are seized with these interventions. IIF has also launched Akshaya Urja, wherein it assists foundries in carrying out energy audits of its operations and preparing an improvement plan. IIF endeavours to carry out Akshaya Urja across the country in the next 2–3 years. With RED to ORANGE to GREEN as our chosen path, I am sure the Green Shoots compendium will add further fillip to IIF’s efforts.

Role of optimised cupola design

Better Design, Better Energy Savings A foundry processes a wide range of iron-containing materials to produce iron castings. Melting is, by far, the most energy-intensive stage in the operation of a foundry. It is also at this stage in melting that maximum pollution is generated by using coke or other fossil fuels. Research institutes and foundries have therefore jointly sought ways to improve the melting process in order to improve overall energy efficiency and reduce pollution.

he conventional cupola is a type of melting furnace commonly used by foundries in India. A cupola is a hollow, vertical cylindrical furnace. It has a single row of pipes known as tuyeres, through which air is blown at room temperature. Such furnaces are called ‘cold blast cupolas’. A number of iron-containing materials such as pig iron, cast iron scrap and foundry returns are loaded into the cupola either manually or by a mechanical charging device. Limestone or dolomite is added as a fluxing agent. Coke is used as fuel. These are charged one after the other to form alternate layers inside the cupola. As the charge melts with the blowing in of air, the limestone/dolomite combines with impurities present to form a slag, which floats atop the heavier molten iron. The slag is removed through a slag hole; the iron is tapped out through a tap hole lower down and moulded into castings. The energy efficiency of a cupola is measured in terms of amount of metal charged/molten metal produced for one tonne of charged coke. This can be denoted either as a ratio or as a percentage, known as Coke Feed Ratio (CFR). The lower the CFR, the more efficient will the cupola be.

The Technology There are many ways to improve the cupola’s energy efficiency. One such way is through its designs, which entail installation of expensive equipment. By optimising the cupola design, it is possible to increase savings in energy.

Say YES to Divided Blast Cupola Reduces coke consumption by 25% Increases tapping temperature by 500C Increases the melting rate

Benefits to the Environment To illustrate the benefits of optimum design, we can consider a Divided Blast Cupola (DBC) that reduces Carbon Monoxide (CO) formation by introducing a secondary air blast at the level of the reduction zone. DBC has two rows of tuyeres, with the upper row located about 1m above the lower row.

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The following causes low energy efficiency  Poor furnace design  Poor operating practices  Non-uniform size of charge material

These factors influence the cupola performance blast rate  Cupola diameter related to melting rate  Blower specification  Tuyeres and shaft length  Lining

Case Study: The Rajkot Cupola Approximately 400 grey iron foundry units, most of the foundry units at Rajkot are small scale and produce less than 100 tonne of casting a month. As a first step, an audit was carried out at Shining Engineers & Founders in November 2002. The existing cupola had three rows of tuyeres and a diameter of 27 inches. The melting rate of the cupola was 3.3 tonne per hour. A common bucket charging system fed the cupola. Given below are the pre-commissioning audit findings: • Charge coke consumption: 9.1% • Ash in coke: 11.4% • Melt temperature at spout: 1,3770–1,4280 Celsius • Temperature of flue gas (below charging door): 3500–4000 • Ferro-silicon consumption: 0.21% of metallics • Ferro-manganese consumption: 0.13% of metallics • Rejected castings: Minimum 7%

Celsius

The DBC designed and customised for the foundry by The Energy And Resources Institute (TERI) had the following specifications: • Number of cupolas: 2 • Desired melting rate: 2.8 tonne per hour • Operation: Continuous • Desired metal temperature at spout: 1,4250–1,4750 Celsius • Diameter: 24 inches

The New Cupola design paid attention to the following aspects  Specification of the blower, the blast rate and the pressure delivered  Proper bed coke height  Dividing the supply of the blast air to the top

and bottom rows of the tuyeres in the correct proportion  Minimising the pressure drop and turbulence of the combustion air through proper sizing and design of the blast main pipe, wind box and tuyeres  Parameters like tuyere area and number of tuyeres  Matching the ladle size to well capacity  Providing greater stack height for better heat exchange between ascending hot gases and descending charge materials  Specifying correct charge properties  Materials specifications, such as the thickness of mild steel plates used in cupola shell and base plates

The post-commissioning audit reported the following findings: • Charge coke consumption: 7.8% • Ash in coke: 12.2% • Melt temperature at spout: 1,4170–1,4620 Celsius • Temperature of flue gas (below charging door): 1320–1620 • Ferro-silicon consumption: Nil • Ferro-manganese consumption: Nil • Rejected castings: About 5%

Celsius

There was a savings of the order of `850 per tonne of molten metal in the foundry unit. For a typical foundry unit, melting about 250 tonne of metal a month, the total savings translates to about `2.2 lakh per month. The capital cost of a DBC, inclusive of civil work, platforms, bucket charging system etc., is about `10,00,000. It is also possible to retrofit a conventional cupola to DBC, by simply changing the blower and blast arrangement. The capital cost of the retrofit option is about `2,00,000. The capital investment, even in a new DBC, usually pays back within a year, depending on the amount of metal melted in the foundry unit.

Conclusion The significance of small, sensible design changes in cupolas can immensely help a company save energy and optimise their resources. In short, the better the design of the cupola, the lesser would be the energy consumption.

Solution User The Energy and Resources Institute (TERI)

Use of heat exchanger in cupolas

Bartering for

A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. During the operation of a cupola, i.e., metal melting, hot flue gases from the cupola eventually escape into the atmosphere. The heat forms flue gases that can be recovered and reused in the melting process.

he media, in a heat exchanger, may be separated by a solid wall, so that they never mix, or come in direct contact. The melting operation in a foundry is an extremely energy-intensive procedure. Therefore, it is not difficult to imagine that the maximum potential with respect to energy savings lies in optimising this process.

A small cupola furnace in operation at Wayne State University, in Detroit, Michigan

Say YES to Heat Exchanger þ þ þ

Better cupola efficiency Less burning of fuel Ease in melting of the metal

The Technology It is a known fact that increasing the incoming blast temperature in a cupola increases melting efficiency and hot metal temperature, reduces coke ratio and improves material quality. The earlier attempts to use cupola waste heat to preheat blast air centred mainly on the use of ‘sensible heat’, as typified by Cameron’s hot blast furnace of 1830s. Herein, a wind box was embedded in the furnace wall lining. However, as cupola furnaces grew in size, the principle was changed to one that utilises the latent heat of combustion by leading the exhaust flue gas to a heat exchanger installed separately.

Zones and temperatures in cupola

Charging door

5400 C Cupola designed by Naniwa Roki Co, Ltd

Pre-heating zone

7600 C

SANES Foundry systems Melting zone 1,0900C Reduction zone 1,3200 C

Oxidation zones Tuyeres

1,5400 C

Tap hole

Bed

Well

Hot gases arising out of burning of coke in a conventional cupola are wasted into the atmosphere. They are generally at a temperature of around 4500 Centigrade to 6000 Centigrade. So is the case with a well-designed Divided Blast Cupola (DBC), in which the flue gas temperatures could range from 2000 Centigrade to 3000 Centigrade. If these gases are trapped and used to heat the fresh air being inducted into the cupola, the cupola’s efficiency increases. SANES supply heat exchanger systems for this purpose, which can be attached to existing cupolas. It can be also made common to two cupolas, one being in operation at a time.

Cross-section - Cupola

Conclusion Over the years, the heat exchanger has enlarged in size. This technology utilises the latent heat of combustion by leading the exhaust flue gas to a heat exchanger installed separately. This would help save more and better use the unutilised flue gas, thus helping the concept of reuse, recycle and refurbish.

Solution Developer SANES

Duplexing

Refurbishing & Recarburising

The Cupola

Development of the cokeless melting furnace began in the UK at the foundry of Hayes Shell Cast Ltd in the mid-1960s. A pilot furnace was built during 1967 to prove the ideas of melting cast iron with gas at a relatively low temperature and then superheating by some other means.

rials established that iron of suitable temperature and composition could be tapped directly from the furnace without any superheating. As a result, one of the existing 5 tonne per hour cupolas, at the foundry of Hayes Shell Cast Ltd was converted into a gas-fired cokeless system in November 1970.

Technology details In conventional coke-fired cupola, the coke has three functions:  It acts as a source of heat  In the bed, it superheats the iron as it trickles over the coke  It acts as a source of carbon

Say YES to Cokeless Cupola Coke not required Significantly reduced or zero pollution Saving in raw material

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Means of adding technology to a cokeless melting furnace  Heat is provided by the burners, which can be fired with a variety of fuels such as natural gas, diesel oil, propane or other suitable fuels  Superheating is done by the specially developed spheres that form the refractory bed  As there is no carbon pickup in the cokeless melting furnace, this is added by continual injection into the well of the cokeless melting furnace.

Implementation Since the invention of the cokeless cupola, many have been installed in various countries including the UK, Germany, Japan, Korea, the UAE, Iran and Chile. From the point of view of India, Indian foundrymen now know that the eco-friendly cokeless cupola technology is available indigenously in the country. To make this possible, a technical collaboration agreement has been signed on December 9, 2005, in Kolkata between Wesman Engineering and Cokeless Cupolas Ltd to offer this technology to Indian users. The agreement specifically covers the exclusive manufacture of the refractory spheres in India. Initially, the spheres are manufactured in Kolkata, but depending on the demand, refractory spheres could also be made in locations where there are clusters of foundries. Under the agreement, it is envisaged that the individual foundry will obtain a licence from Cokeless Cupolas Ltd. The licence fee will be dependent on the melt rate of the cupola at £2,000 per tonne of cupola capacity. Thus, it will be £6,000 for a 3TPH cokeless cupola and £10,000 for a 5 TPH cupola.

What is Duplexing? Cokeless melting furnace is an efficient melting unit as cold material is added to the top; the metal is preheated as it moves down the shaft. After melting, it is superheated while being passed through the bed. If high temperature metal is required from a coke cupola, the coke consumption is increased considerably. In the case of gas/oil-fired cokeless melting furnace, this also increases the consumption of the bed material. Hence, superheating is less economical in both cases. An electric furnace is not a very efficient melting unit, but once the metal is liquid, iron can be superheated efficiently. Therefore, melting iron in cupola at low temperature and superheating in an electric furnace is a very cost-effective combination. This is called duplexing. In duplexing, a low bed of around 250 mm is used corresponding to only two rows of spheres, which when new are approximately 150 mm in diameter. This dramatically reduces the consumption of bed material. Reduced bed height reduces the tapping temperature, but increases the melting rate. Therefore, compared with a unit melter, the overall gas consumption also reduces.

What is Unit Melting? Cokeless Melting Furnace technology can be applied in a traditional manner as a unit melter when a high temperature metal of the right composition is available directly from the cupola into ladles for pouring into moulds. This type of operation has been applied in many foundries in different countries, but it is generally limited to smaller and medium-sized foundries operating up to 4–5 tonne per hour and melting for up to 8 hours per day. In a unit melter, fairly high tapping temperatures will be required. To achieve tapping temperatures of around 1,4500–1,4600 C, a bed height of around 650 mm Carbon injection unit and entry point would be required. This means higher rate of consumption of spheres. However, if lower on the Cokeless Melting Furnace shell temperatures are sufficient, then the bed height can be reduced. This, in turn, will reduce the sphere consumption. Since the spheres will not provide the necessary carbon, and since in the Cokeless Melting Furnace there is approximately a 10% carbon loss during melting, with the usual charge make up, it will be necessary to add some carbon to the iron. A carbon injection unit, therefore, will be required, which continually blows carbon into the cupola during melting. The rate of injection can be controlled.

Conclusion The Cokeless Melting Furnace is operated with partially reducing conditions. It is very important that the correct air/fuel ratio is maintained at all times; otherwise, the required temperature will not be achieved as the furnace temperature reduces steeply with both excess fuel and excess air condition. An automatic control system forms part of the main control panel and the air and fuel flows to each burner are also monitored. These, if done, would help conserve the environment.

Solution Providers Wesman Engineering and Cokeless Cupolas Ltd

MF & dual track induction furnace and IGBT technology

Increasing Melt Efficiency The manufacture of induction furnaces has seen tremendous growth in the last couple of years. Advances in technology have seen induction furnace manufacturers come up with innovations that have helped to reduce energy consumption in industrial and domestic applications. The technology uses the same functioning principles as that of transformers. The furnaces work by heating electrical conductors through currents that are induced by a fluctuating electromagnetic field. The use of induction furnace has reduced problems that had been difficult to control when using arc furnace.

edium frequency furnace operations are a key casting industry process used for melting metals, maintaining molten metals at the prescribed temperature, and warming and adjusting components. In contrast to the cupola, which is a continuous melting furnace, induction furnaces operate with a melting cycle that depends on their operational frequency. There are two main classifications of coreless induction furnaces, i.e., mains

frequency units and medium frequency units. Mains frequency furnaces tap about one-third of the molten charge, leaving the remainder to serve as a molten heel to initiate the melting of the next charge. Medium frequency furnaces sometimes completely tap the molten contents of the furnace and begin the next melting sequence with a cold charge. In order to optimise induction furnace efficiency, the Insulated Gate Bipolar Transistor (IGBT) technology and Dual Track technology are being developed and applied.

Say YES to MF induction furnaces Good operation efficiency Cleaner operation Lesser emissions

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Induction melting process advantages  Batch melting has lower tonnage requirements  The process allows precise metallurgical quality control  There are fewer environmental concerns than cupola melting

 Induction is the simplest and least costly way to enter the casting business on a small scale.

Dual Track furnaces based on IGBT technology have helped to increase the efficiency of the induction furnace to levels not seen before. The equipment comes with in-built circuitry that enables users to closely monitor load power and sanctioned demand, which is useful for ensuring that the equipment can be run efficiently on the most optimum power margin.

The Technology Medium Frequency Induction Furnace From the point of view of foundry applications, theoretically, the furnace operation with maximum available electrical power and, thus, higher power density, is most favourable. The power consumption decreases with increasing nominal power at the same furnace size, since with increasing power density, the proportion of energy for thermal losses decreases because of the three times as high power density per tonne crucible contents. This makes medium frequency induction furnaces more efficient than other types of induction furnaces. The medium frequency furnaces can be started with cold feedstock. This is because under the Curie point (9000C), much higher coil efficiency can be reached. Owing to decreased melting time, heat losses are lowered.

Necessary transformater effective power

100% 2%

Losses transformer condenser feed cable

Furnace actual power output Electrical 20% heat losses

Induced power

Actual power output

70%

Heat losses crucible wall

IGBT Technology The Sankey diagram - MF Induction furnace There are different induction melting furnaces available including tri track, dual track and tetra track furnaces. These furnaces are based on IGBT technology, which has helped to increase the efficiency of the induction furnace to levels not seen before. The furnaces have helped to reduce electrical losses by a big margin. They provide efficient melting rate as well as unit consumption. The equipment comes with in-built circuitry that enables users to closely monitor load power and sanctioned demand. This is useful for ensuring that the equipment can be run efficiently on the most optimum power margin. IGBT, a three-terminal power semiconductor device primarily used as an electronic switch and in newer devices, is noted for combining high efficiency and fast switching. It switches electric power in many modern appliances—electric cars, trains, variable speed refrigerators, air-conditioners and even stereo systems with switching amplifiers. Since it is designed to turn on and off rapidly, amplifiers that use it often synthesise complex waveforms with pulse width modulation and low-pass filters. In switching applications, modern devices boast pulse repetition rates well into the ultrasonic range (frequencies which are at least 10 times the highest audio frequency handled by the device when used as an analogue audio amplifier).

The IGBT

Dual Track Induction Furnace A Dual Track Induction Furnace uses a single energy source and two furnaces. As per a case study carried out by Banaras Hindu University, it was determined that a medium-scale foundry in India can save considerable amount of energy using Dual Track Furnaces. In the foundry under consideration, it was found that overheating of the liquid metal played a significant role in increasing the SEC. For instance, an increase of 100C, results in additional energy consumption of 15–20 kWh per tonne of metal. It was estimated that the replacement of Main Frequency Induction Furnaces by Dual Track Induction Furnaces can result in energy savings to the tune of 55 units per tonne. The use of IGBT technology ensures greater control on power frequency.

Implementation The use of medium frequency induction furnaces in combination with improved shop floor practices has made a considerable difference in energy consumption at Tata Motors Ltd, Jamshedpur. The following aspects of the furnace operation were investigated and improved in order to achieve tangible results:

 Improved lining material  Scrap charging sequence

 Power input  Deslagging

Conclusion The use of the induction furnace in the steel industry has proved to be phenomenal; different frequencies can be used in steel making to come up with different grades of steel. The technologically advanced induction equipment is of high quality, giving the users precision and accuracy in all their needs. While cupola, reverberatory and electric arc furnaces may emit particulate matter, carbon monoxide, hydrocarbons, sulphur dioxide, nitrogen oxides, small quantities of chloride & fluoride compounds, and metallic fumes from the condensation of volatised metal & metal oxides, induction furnaces emit comparatively small amounts of particulate matter, carbon monoxide and hydrocarbons. Usage of these can benefit the industry and help safeguard the environment.

Solution Users MF Induction Furnaces: Tata Motors Ltd IGBT & Dual Track technologies: Inductotherm India

Energy conservation in cooling towers

Lightweight

Cooling Cooling towers in foundries are used for operations such as mould sand reclamation, electric arc and induction furnaces, in shell mould and shell core machines, permanent moulds cooling and quenchers. Cooling towers work on producing cooler water through an evaporative process.

he purpose of a cooling tower fan is to move a specified quantity of air through the system, overcoming the system resistance— this is defined as pressure loss. The product of air-flow and pressure loss is air/power developed/work done by the fan. The fan efficiency is greatly dependent on the profile of the blade. An aerodynamic profile with optimum twist, taper and higher coefficient of life to coefficient of drop ratio can provide the fan a total efficiency as high as 85–92%. However, this efficiency can be immensely affected by

factors such as tip clearance, obstacles to air-flow and inlet shape, among others. It is difficult to fabricate metallic blades with the ideal aerodynamic profiles as neither extrusion nor casting processes enable such high accuracy. The Fiberglass Reinforced Plastics (FRP) blades are normally hand moulded, which facilitates the generation of an optimum aerodynamic profile. Replacement of aluminium blades with lightweight FRP blades reduces the load on cooling tower fan motors & brings down energy consumption, in some cases, by 20–30%.

Benefits to the Environment Lightweight Energy savings Improves life of gearbox Less frequent maintenance Enhances motor life

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Over time, metal blades may corrode and rust from moisture or chemical exposure. Fiberglass industrial fans are considerably more durable than standard metal fans. That depends on the type of metal used and the thickness of the blade material. A sheet metal fabricated blade is typically lighter than the one made of cast aluminium. An industrial fiberglass blade of the same size and profile is usually heavier than a fabricated blade, but lighter than a cast aluminium blade. The compression strength to weight ratio of fiberglass is excellent as compared to either fabricated or cast aluminium blades. Generally, the larger the diameter, the greater the difference in weight between fiberglass and metallic industrial fans (fiberglass fans tend to be lighter in comparison to metallic fans for larger diameters and are therefore, easier to handle and install). In most installations where a metallic fan is being replaced by an industrial fiberglass or FRP fan, energy savings will be realised. In some instances, energy savings of up to 45% have been achieved when using industrial fans. In most cases, depending on the actual energy savings, the capital cost of installing an industrial fiberglass fan can be recovered over a short period of time. Industrial fiberglass fans can offer a good low noise fan solution. They have optimised blade profiles that are normally quieter in operation and generate less blade vibration than metal fans.

Implementation

The Technology

39000 2.6

27300

7800

1.82 1.56

Power drawn (kW)

23400

5460 4680

Energy used in 3,000 hours

5 HP motor for cooling tower fan with Al blades

6396 4477 3838

Annual energy cost (`)

With FRP blades

Equivalent CO2 emissions p.a. (kg)

Savings with FRP blades for 2 cooling towers

FRP v/s Conventional

Easier to manufacture Faster payback Low starting torque Less powerful motor Easier maintenance

Metal fan blades are difficult to manufacture Metal or glass requires 6â&#x20AC;&#x201C;7 months for payback High starting torque More powerful motor Tougher maintenance

FRP Blade Fans for Cooling Towers developed by Cool Deck India LTD A number of companies in India develop FRP blade fans for cooling towers; one such company is Mumbai-based Cool Deck India Ltd, part of the Bhargava Group of Industries. The aerofoil design ensures high efficiency, lower noise levels and less power consumption. Reinforced Fiberglass Epoxy Resin provides the desired non-corrosive quality to the fan blades, resulting in the operation of fans even in the most aggressive environment. The design of the fans provides high air volume with optimum pressure to ensure the long distance reach in the farthest areas. The hollow construction of blades makes the fan lightweight, resulting into low starting torque and reduced power consumption under varying load conditions. This causes minimum wear and

stress on motor bearings and drive shafts. Benefits Cool Deck has estimated that FRP blade fans provide 30% power saving or up to 10% extra airflow. As a result, the usual payback period for replacing aluminium fans is only 4â&#x20AC;&#x201C;6 months. In a condition when power consumption is the important factor, blade angles are set to give the required airflow at the lowest power consumption. Alternately, for the toughest duty condition when the airflow requirement is the highest, the blade angles can be set to give maximum performance from the existing conditions of power consumption. Any of these advantages can be suitably chosen at the time of fan installation.

Conclusion Because metal fans are usually cut from metal sheets and bent to shape, there is a limitation in producing optimum blade profiles. On the other hand, intricate optimised computer-generated aerodynamic blade profiles can be duplicated with precision by moulding fiberglass into fan blades that maximise airflow and are more efficient in power demand and airflow output. Furthermore, industrial fiberglass fan blades generally have a longer life span as they are less affected by moisture, humidity and corrosive chemicals.

Solution Developer Cool Deck India Ltd, part of the Bhargava Group of Industries

Use of VFDs in cooling towers

Drives Cooling water in foundries is used for operations such as mould sand reclamation, electric arc and induction furnaces, in shell mould and shell core machines, permanent moulds cooling and quenchers. Cooling towers produce cooler water through an evaporative process. Cooling towers may be categorised into natural or mechanical draft. Mechanical draft towers can subsequently be categorised into forced draft and induced draft towers. Both these designs use one or more fans to provide the flow required to extract heat from process cooling water.

ooling tower operation can be one of the largest water and energy-consuming activities for many foundry operators. Cooling towers can account for up to 60% of a manufacturing site’s water use. Hence, all electrical melting furnaces need to be equipped with cooling systems to avoid surplus heating, which, in turn, could cause damage to induction furnace coils or the steel structures in electric arc furnaces. In these types of furnaces, the cooling effect represents around 20% of input prime energy. This represents about 100kWh/ tonne of melted metal. In addition, cupola furnaces emit a lot of surplus heat. While cupolas may be cooled down externally by water, the exhaust gases contain lots of energy because of the high temperature and Carbon Monoxide (CO) content. The energy of exhaust gases can be

Motor protection Energy saving Nominal costs Long run 98

VFD

recovered by using CO ignition and water coils in the exhaust gas flow. Most foundries recycle the mould sand around 3–8 times. The sand reclamation system contains a sand cooling system as well. The recycled molding sand cannot be extremely cool or extremely hot; it is usually used at a temperature of 20⁰–40⁰C. In the shakeout stage, the sand temperature can vary from room temperature to around 400⁰C. The weight ratio of the moulding sand to castings is usually 1:5, i.e., for one tonne of casting, the mould contains about five tonne of sand. This means that the amount of heat recovered from sand cooling is the same as the amount which can be recovered from furnace cooling. Thus, the saving potential can be calculated as 100 kWh/tonne castings.

Say Yes to VFDs Automation protection

Fan speed controlled by VFD

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One of the most beneficial ways of increasing cooling tower efficiency and lower energy costs is by using a VFD.

VFDs can be retrofit on existing equipment.

The Technology The installation of Variable Frequency Drives (VFDs) has proved to be beneficial on cooling tower fans. Fans regulate the airflow to compensate for changes in ambient air and load conditions. In the past, this was achieved by cycling fans on and off, manipulating fan capacity by varying the pitch of the fan blades, or using two-speed motors. These methods have considerable drawbacks and do not leave much room for error. Across the line motor operation can be efficient if a system is designed to operate at full speed 100% of the times; this is rarely the case. In reality, as conditions change, the flow needs to change as well. As a fan cycles on and off, its speed alters dramatically, causing leaving water temperature to fluctuate, leading to inefficiency and making it difficult to control the same.

Benefits to Environment Fan motors consume a large amount of electricity owing to the high inrush of current that is required to start the motor every time it is cycled. VFDs eliminate this problem by acting as soft-starters, increasing/decreasing speed at a programmable rate. This feature reduces mechanical wear by eliminating stress on the power train caused by across the line motor starting. This can increase system life and save maintenance costs.

Case Study: IC Engineering Solutions, Florida Base Scope

$13,210

Base Scope

$11,000

1.2 years /

83% ROI Summary of first year savings Projected annual electrical savings

Job Cost

Projected Payback/Return on Investment (approx.)

The case study carried out by IC Engineering Solutions, USA, illustrates the benefits of VFDs in cooling towers given two existing cooling towers rated for 1,200 GPM each while operating on two-speed 30 HP fans. The cooling towers were designed around a 950 Entering Water Temperature (EWT) and 850 Leaving Water Temperature (LWT) at 800 wet bulb. With this fan configuration, it is estimated that the fanâ&#x20AC;&#x2122;s operating costs are $20,366 per year. It was decided that one cooling tower cell fan would be furnished and installed with a 30-HP VFD. This would be provided the electrical support as required. Also, provided would be Trane Heating, Ventilation, And Air Conditioning (HVAC) controls as required to implement cooling tower fan VFD. The price of this installation was $13,210. The graph alongside enumerates the savings and return on investment for retrofitting VFDs on cooling tower fans.

Deriving The VFDs = Energy Efficiency Equation Fan speed: VFDs are able to adjust fan speed as conditions change while maintaining the exact flow required. Owing to their built-in proportional-integral capabilities, VFDs automatically adjust the fan speed to maintain a given set point, thus eliminating the need for an external set point controller or variable pitch fan. VFDs can reduce energy consumption by simply slowing the motor. A fanâ&#x20AC;&#x2122;s speed varied proportionally with the cube of its speed, so a small reduction in fan speed results in a large power reduction. Automation and motor protection: Using a VFD on a cooling tower fan is also valuable for automation and motor protection. VFDs have digital and analogue inputs, outputs, programmable relays & numerous serial-communication options that allow for flexibility in tower automation and performance monitoring.

Conclusion As conditions change in a cooling tower, the flow needs to change. As a fan cycles on and off, its speed alters dramatically, causing leaving water temperature to fluctuate and leading to inefficiency & control difficulty. VFDs, if installed, can prove beneficial. Also, across the line motor operation can be efficient if a system is designed to operate at full speed 100% of the time.

Solution User IC Engineering Solutions, USA

Environmentally-friendly resins

re-polymers of furan resins are delivered to foundries as liquids in which the furfural alcohol content varies between 50% and 95%. They are polymerised into insoluble macromolecules by the action of an acid catalyst. Phosphoric acid or paratolouene sulphonic acid is used for hardening the resins. Although effective, a major disadvantage of furan resins is that irritating gases are formed during sand mixing. Small quantities of free furfural acid, free formaldehyde and free phenol vaporise during the process of sand mixing and filling into core boxes. An exothermic hardening reaction increases the evaporation. The pyrolysis of furan resins during the casting produces carbon monoxide and, possibly, small amounts of formaldehyde, phenol and nitrogen oxide. These gases are toxic and can cause irritation of eyes and skin as well as breathing difficulties among workmen. As a result of the demonstrated toxicity by furan resins, scientists are in the process of developing eco-friendly resins that are clean, biodegradable and water soluble.

The benefits of alpha-set resins are most noticeable in steel castings.

100

Alkaline Phenolic Resins do not use harmful acid catalysts, which would harm not only the environment but also human beings.

e v i s n o p

s e r e r u t Na

ard to a h e n i d n sa inc cure’ used s o r d n n e a e b larly f o ‘ f o r m esins have u t c i t d r e a e s c a l s u ting furan r f o r s a n d , p n f a s t , h a v i m e h rde lly, -set nts are c . Cold inding age se resins ha g. Chemica e Resins p a h s b the urea ed s astin mould 0s mainly a made with asily after c with either ins e 6 s es ol the 19 cores. Core nd collapse rfuryl alcoh rea-furan r ng. a i U u g nsions lymers of f yde resins. n steel found makin e m i d po eh te si accura nders are co nol formald l-furan resin i e o b furan ehyde or ph ng and phen i d d l forma in iron foun ed are us

ns i s Re

Say Yes to Alkaline Phenolic Resins Clean Safe Alternative to furan resins Free of heavy metals Lower emissions Elimination of harmful gases

þ þ þ þ þ þ

The Technology New environment-friendly resins are water soluble alkaline phenolic resins or alpha-set resins. These are mixed with sand and are then hardened by gassing carbon dioxide. With time and further R&D, cores bonded using such resins and demonstrate good thermal properties and casting quality on nearly all alloys. Besides, these binders are extremely clean, non-flammable water-based systems that require no scrubber system during coremaking or casting. Odour, fumes and Volatile Organic Compounds (VOC) emissions at coremaking, pouring and shakeout are significantly lower than with most other foundry resin processes. The absence of sulphur, nitrogen or phosphorous in these new-age resins ensures casting free of defects associated with these elements. In addition, the potential for carbon pick-up is negligible. The level of free phenol and free formaldehyde is very low as compared to the furan resin systems.

Implementation FOSECO UK has developed an alkaline phenolic resin called ECOLETEC that is environment-friendly and has demonstrated good casting properties in a variety of alloys. Other companies to have developed alkaline phenolic resins are IVP and Ashland USA.

Conclusion These resins are eco-friendly and use minimal possessions of Mother Nature. With time and further R&D, such resins can demonstrate good effects for becoming the ‘instead of’ material for many presently used materials which are potentially harmful. Nature-responsive resins are some of the developments that the future needs us to implement now so that we could preserve the environment for our successors.

Solution Provider FOSECO UK

101

Variable frequency drives

Adding energy efficiency to screw compressors Live Demonstration

Power consumption per annum

`88.35 lakh/annum

`107.63 lakh/annum

20.79 lakh kWh

516 hp

Motor capacity

ost foundries use rotary screw compressors owing to its easy installation. Air compression can be an extremely inefficient process. In fact, up to 80% of electricity input can be lost as waste heat. There are various methods for improving energy efficiency such as through adding heat recovery equipment and also high-efficiency motors. But for foundries, installing VFDs on screw compressors has helped optimise energy consumption.

25.32 lakh kWh

Screw Compressor wth VFD

630 hp

Compressed air is widely used in foundries for a variety of tasks including blowing sand into or off molds, pneumatic transport, spray coating or cleaning. Rotary screw air compressors are positive displacement compressors. The most common rotary air compressor is the single stage helical or spiral lobe oil flooded screw air compressor. Rotary screw compressors can be fitted with Variable Frequency Drives (VFDs) during operation, which would increase their efficiency.

In order to demonstrate the effectiveness of a VFD on a screw compressor, Mahindra and Mahindra, Kandivili, Mumbai, carried out a case study that demonstrated screw compressor performance before and after the retrofitment of a VFD. The results are illustrated below:

Saving=

`19.20 lakh/annum

Operating cost

Before Installation

After Installation

For 2,200 cfm output compressed air requirement, plant was running four compressors having total motor capacity of 630 hp.

Screw compressor with VFD running in combination with existing compressors having total motor capacity of 516 hp.

receiver tank

pressure flow controller

air filter

7 distribution lines

dryer end points

3 aftercooler

Types of air compressors ď&#x20AC;´ Reciprocating ď&#x20AC;´ Rotary screw ď&#x20AC;´ Rotary centrifugal

1 inlet filter remote air intake

compressor

Compressor package enclosure The above diagram is a typical compressed air system. The inlet filter (1) removes any particles from the outside air before it enters the compressor. The compressor (2) then increases the pressure on the air, making it hot and wet. The aftercooler (3) helps to cool the air and remove moisture before it travels to a dryer (4) that will eliminate any remaining water. An air filter (5) removes any remaining solids before the compressed air is stored in a receiver tank (6). When the compressed air is released, it travels from the tank along distribution lines (7) to individual tools or end points (8). Any moisture that condenses in the air lines is caught and removed by condensate traps.

102

Say Yes to Screw Compressors with VFDs þ Regulate speed, rotational force, torque output of electric motors þ Prevent wastage of energy & dramatic reduction in power usage þ Precisely match motor speed with cooling requirements þ Negligible maintenance þ Better life spans than reciprocating compressors þ Longer life span than centrifugal compressors þ Provide greater efficiency

Leakage losses: Leaks not only waste energy but also cause pressure drops that can adversely affect the operation of air-using equipment and tools, reducing production efficiency.

Air pressure: This should be the minimum required for the end use application. This can be determined by investigating the pressure required by equipment and tools. In some cases, isolated pieces of equipment may require significantly higher pressure. Redesigning individual items or installing a second compressor to service these items may be more cost effective. Some sites are divided into high and low pressure networks.

Air temperature: Up to 6% of a compressor’s power can be saved by using cool inlet air that requires less energy to compress. For every 300 Celsius reduction in inlet temperature, there is a 1% reduction in energy usage.

The Technology Rotary screw compressors consist of two rotors within a casing wherein the rotors compress the air internally. There are no valves and screw compressors to ensure that there are fewer leaks. In fact, the only moving parts in a screw compressor are the male and female rotor. Elimination of pistons, rings, valves, etc., means less maintenance is required. These units are basically oil cooled (with air cooled or water cooled oil coolers) where the oil seals the internal clearances. Since the cooling takes place right inside the compressor, the working parts never experience extreme operating temperatures. The rotary compressor, therefore, is an air cooled or water cooled compressor package that is continuously on duty. In addition, screw compressors have the ability to vary suction volume internally while reducing part load consumption. Screws provide a much wider operating range and lower maintenance costs than conventional reciprocating machines. Besides, these machines are smaller and create much lower vibration levels than piston machines. In order to increase their efficiency, screw compressors can be fitted with VFDs during operation. VFDs operate the motor and torque by varying motor input frequency and voltage. This enables the motor to operate at varying speeds as per the functional requirement and thus, results in better energy utilisation. For positive displacement compressors, speed is independent of lift; the compressor can develop the same amount of lift at any speed. Therefore, mechanical loaders can be replaced entirely by speed control. Centrifugal compressors may require speed control coupled with some closure of the inlet guide vanes. The variable speed screw compressor never has to temper speed control with a guide vane or slide valve, and therefore, capture the maximum energy reduction available at a given operating condition. Even small changes in speed create significant changes in energy consumption. Combine this incremental advantage with superior compression efficiencies, and a clear picture of the energy savings potential of this technology can be determined.

Conclusion A compressed air system helps to better the efficiency by removing any outside particles; increasing the pressure of air by making it hot and wet; cooling the air removing moisture from it and eliminating the remaining water particles and finally, removing the remaining solids. The compressed air travels and distributes to individual tools. Using compressed air helps to reduce energy and thus save the environment.

Solution Provider Mahindra and Mahindra

103

Simulation casting software

From

P OW ER SAVIN G

reality

wast e reduc t i o n

idea to Ecofriendly

Foundries try to reduce rejections and thereby energy consumption and material wastage by experimenting with process parameters (like alloy composition, mould coating, and pouring temperature). When these measures are ineffective, then methods design (i.e., gating and feeding) are modified. But when even this is not effective, then tooling design (i.e., part orientation, parting line, cores and cavity layout) is modified. Assuming that a typical foundry develops 50 new castings every year, each casting requires at least two trials, it is not difficult to imagine the kind of energy and material wastage foundries have to deal with. Casting simulation can overcome such problems.

he effect of any change in tooling, methods or process parameters is ascertained by pouring and inspecting test castings. Studies show that replacing shop floor trials by computer simulation saves time, provides better insight and helps in reducing the rejections by half—from an average 8.6% before to 4.3% after, as per a survey of nearly 200 foundries carried out by IIT Bombay. This is, however, still very high as compared to the expectations of Original Equipment Manufacturers (OEM). The applications results in the reduction of native materials that must be mined or landfilled elsewhere.

AutoCAST-X simulation @ work in  AutoCAST-X simulation @ work  Precicast, Gurgaon  Cummins Turbo, Pune  Gosain Foundry and Engineering Works, Ludhiana  Bajaj Auto, Pune  Grey Duct Foundry Services, Ambala  Guindy Machine Tools

104

Say yes to Simulation Casting Software Easily identifies defects Potential improvements in design and technology Reduces need for developing multiple prototypes Enhanced quality Saves raw material, energy and time

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The Technology Casting simulation can overcome various virtual problems: virtual trials do not involve wastage of material, energy and labour, and do not hold up regular production. Metal casting solidification software are designed to improve the quality and yield of metal casts. In addition, an application that is a web-based system, which links to a manufacturer’s Computer Aided Design (CAD) software, can simulate a part before it has been cast. Using a Gradient Vector Method (GVM), simulations increase the reliability of metal parts by showing the heat signatures of the solidifying part. Viewing hot spots of the solidifying metal parts before an actual pour allows defects to be addressed, enhancing the quality of the finished part and overall reducing energy & material wastage that would otherwise have been used for making trial components.

Implementation The AutoCAST software developed by Advanced Reasoning Technologies, Mumbai, in collaboration with IIT Bombay, provides a single integrated user-friendly environment for casting methods design, solid modelling and simulation. It handles both ferrous and non-ferrous parts as well as sand and metal moulds. It also incorporates a multi-cavity mould layout, automatic modelling and optimisation and a costing model to compare various layouts. It does not require sophisticated equipment and can be operated within 400 GB of hardware space. IIT Bombay collaborates closely with IIF Kolkata in training foundry experts in this simulation package. There are several simulation software in the market, AutoCAST-X being just one of them. One of the more sophisticated ones is MAGMA that enables features such as mould filling, etc. Although more advanced, MAGMA is a lot more expensive than other simulation software.

Conclusion Casting simulation helps to triumph over virtual trials. It does not involve wastage of material, energy and labour or even hold up regular production. Such software designs improve the quality and yield of metal casts. The applications also are web-based and thus help the manufacturer link CAD software and simulate a part before it has been cast.

Innovators Advanced Reasoning Technologies, Mumbai, in collaboration with IIT Bombay

105

Automatic fettling

Trimming the

Way Fettling and dressing (or trimming) are the terms traditionally given to the finishing of castings to remove excess or unwanted metal, e.g. flashings, risers, etc. It can include processes such as grinding, chipping and shot blasting. The introduction of automatic or semi-automatic fettling, e.g. fettling robots, CNC grinding machines, cropping etc., are not only efficient but also safe for employees.

and-held tools such as grinders and chipping hammers, or fixed tools such as pedestal grinding machines, linishers and bandsaws, are traditionally used to remove unwanted metal. Automated fettling is becoming more common today in a variety of ways; albeit recently, its applications are limited.

Very high noise levels are produced during fettling, mainly during chipping, and may exceed 117 dB. Personal noise exposure levels of 100â&#x20AC;&#x201C;110 dB have regularly been measured during routine fettling operations in both ferrous and non-ferrous foundries. These are harmful for operators and can cause medical problems in addition to low productivity. In order to curb noise pollution, automation of the fettling operation is being implemented in foundries.

The Technology The introduction of automatic or semi-automatic fettling, e.g. fettling robots, CNC grinding machines, cropping, etc., will ensure safety of employees. In cases where these techniques are used, noise levels can often be further reduced by fitting acoustic guards or enclosures. Whether such engineering controls are reasonably practicable will depend on the volume of product, the nature of the process involved, and the types of castings produced. Automation or mechanisation of fettling is steadily becoming a more practicable and cheaper option although mechanical fettling is likely to be required for intricate castings and where a variety of castings are produced in small numbers. Although automatic fettling can make a tangible difference, it is more suited to larger units. This is the reason why, in India, only major foundries have implemented automatic fettling.

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Manual fettling, high effortsâ&#x20AC;&#x201C;low output, no defined work area, no proper tools, and dirty work area

Image Courtesy: KUKA Robotics (India) Pvt Ltd

Why Say Yes to Automated Fettling? Low noise levels Safer working conditions (for operators) Better ergonomics Cleaner shop floors

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Implementation Automatic fettling can be implemented simply. Machines called ‘snag grinders’ help automate the fettling process. Snag grinders are horizontal milling machines that have a grinding wheel in place of milling cutters. These machines are constructed in a way that the grinding of two faces can take place at once. Grinders are also quieter than the conventional clippers, thus helping address the issue of noise pollution.

Automatic Fettling at Involute Automation A UNIDO-ICAMT Initiative for the Hyderabad Machine Tool Cluster UNIDO-ICAMT has enabled Involute Automation Pvt Ltd, a foundry that is part of the Hyderabad cluster to implement automatic fettling. Earlier, Involute manufactured standard auto pourers, sprayers and extractors for the die-casting industry. As per the diagnostic study conducted and action plan prepared by UNIDO-ICAMT, Involute has now initiated manufacturing of gantry automatic pourers, vision inspection lines and automatic fettling lines for cast components.

Conclusion Automatic or semi-automatic fettling removes employees from risk by reducing noise levels by fitting acoustic guards or enclosures. Although automatic fettling can make a tangible difference, it is more suited to larger units. This is the reason why in India, only major foundries have implemented automatic fettling.

Solution Provider Involute Automation Pvt Ltd

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and reclamation usually requires a combination of mechanical and/or thermal processes to recondition it for reuse in the coremaking process or green sand system. To date, both reclamation processes have required significant demands in energy to make spent green and core sands reusable in the foundry. Nonetheless, the beneficial reuse of foundry sand and recovery of their additives has gained a lot of popularity in recent years due to its other

environmental benefits. Spent foundry sands have been used successfully as a source of silica for cement production, flowable fill for construction, roadbeds and geotechnical fill for a variety of projects. A more recent development for spent sands has been in the use of soil amendments for croplands in the agricultural industry. Apart from this, every tonne of foundry sand or slag used in any of the mentioned applications results in the reduction of native materials that must be mined or landfilled elsewhere.

The Technology Cores are used for making the desired cavities/shapes in a sand mould in which molten metal is cast/poured. Cores are primarily composed of silica sand with small percentages of either organic or inorganic binders. Sand usually makes up 50â&#x20AC;&#x201C;95% of the total materials. United States Environmental Protection Agency (USEPA) has estimated that the US annually generates approximately 15 million tonne of byproductsâ&#x20AC;&#x201D;most of which are landfilled. Landfilling is not a viable option owing to not just huge costs associated with disposal but also environmental concerns. One innovative solution appears to be the high-volume uses of foundry byproducts in construction materials.

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45% weight of

foundary sand is used as a replacement of regular sand to meet the needs of structural-grade concrete.

42MPa concrete 85% flowable of compressive strength has been produced with the inclusion of foundry sand.

slurry has been produced by incorporating used foundry sand as a replacement for fly ash.

15% used

foundry sand can be utilised as a replacement of fine aggregate in hot mix asphalt.

Foundry (cupola) slag is appropriate for use as a coarse semi-lightweight aggregate in cement-based materials. It has been used as a replacement for aggregate in the manufacturing of structural-grade concrete.

Recycling spent foundry sand

Building a sustainable future Spent moulding sand has received a great deal of attention in the last couple of decades. It can be reclaimed internally, or beneficially reused by altogether another industry. One way of minimising foundry sands’ consumption during casting is by using mould boxes rather than cake moulds. In India, the idea of recycling foundry sand has taken off with the Belgaum Foundry Cluster (BFC) establishing the first common facility for sand reclamation plant in the country for small and medium foundries.

Benefits to the Environment

BFC’s half of fame: The first sand reclamation plant in India

Generally, large volumes of byproduct materials are disposed of in landfills. However, owing to stricter environmental regulations, particularly in developed countries, the disposal cost is escalating.

Belgaum Foundry Cluster (BFC) has quality testing laboratories enabled with advanced Optical Emission Spectrometer (OES) and 3D Coordinate Measuring Machine (CMM); common tool room; simulation, 3D modelling and ERP software modules; Common Effluent Treatment Plant (CETP). BFC has also been working on overall better infrastructure such as resurfacing of roads, working on itself to becoming a truly world-class castings hub. The hall of fame of BFC is the sand reclamation plant, the first of its kind in India, which can recycle 10,000 tonne of sand per month. This cuts costs and saves the foundry units from purchasing sand. Sand is a major raw material used in preparing casting models. Earlier, foundries used to purchase sand every year. Recycling sand is cost effective and ensures increased productivity. The recycling of non-hazardous, spent foundry sand can save energy, reduce the need to mine virgin materials, and may reduce costs for both producers and end users. For instance, it has been found that the use of spent foundry sands as construction site base material in cold weather extends the construction season because such sands will not freeze as easily as most soils. In addition, use of foundry sand from iron, steel, aluminium foundries in flowable fill, road embankments, road base, manufactured soil, agricultural amendments and similar uses may be appropriate depending on the site and the sand composition. For these applications, characterisation of the sand and a site-specific assessment are required before use.

Recycling helps not only to reduce disposal costs but also to conserve natural resources. Foundry sand can be used as a partial replacement of regular sand in concrete, flowable slurry, cast-concrete products and other cement-based materials. Foundry slag can be used as semi-lightweight coarse aggregate in concrete.

Foundry byproducts  Foundry sand  Core butts  Abrasives  Cupola slag Conclusion Landfilling in construction and mining sites is not a viable option owing to not just huge costs associated with disposal but also due to environmental concerns. This innovative solution of using high-volume foundry byproducts in construction material appears to be the best available solution. This, if used, would help do away with landfill sites and would make the globe a greenery place.

Solution Provider Belgaum Foundry Cluster

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Precision granite

Machine tools and other high precision machines in the metrology field rely upon high stiffness, long-term stability and excellent damping characteristics of the base material for their static and dynamic performance, designers are now looking for alternative materials for their structures to improve the performance of their machines and make them more cost-effective in their production.

resently, the most widely used materials for making structures are cast iron, natural granite and welded steel fabrications. However, these materials have advantages and disadvantages. Steel fabricated structures are seldom used where high

precision is required due to the lack of long-term stability and very poor damping properties. Good quality cast iron, which is stress-relieved and annealed, will give the structure dimensional stability and can be cast into complex shapes; it needs an expensive machining process to form precision surfaces after casting.

The Technology Structures in natural granite distort in the presence of water and coolant vapours; they are excessively heavy due to the solidness of the structure. Precision granite castings, sometimes known as synthetic granite, epoxy granite or polymer concrete, overcome many of these disadvantages and possess most of the advantages of conventional materials, and, in some cases, even better them. Precision granite castings, also called Polymer Castings (PC), are produced by mixing granite aggregates, which are crushed, river-washed, kiln-dried and mixed with an epoxy resin system at ambient temperatures (i.e., cold curing process). The mineral aggregates are precisely graded and range in sizeâ&#x20AC;&#x201D;from a fine powder to particles 0.375 in diameter. Precise grading minimises air voids and resin use and promotes stronger castings. In general, castings incorporate coarser aggregates, though fine aggregates fill thin sections better. The mechanical properties of polymer castings are about the same, regardless of aggregate size.

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Over the last decade, a number of machine manufacturers have encompassed the use of synthetic casting materials in their machine structures. A great deal of know-how has been developed over the past decades to exploit these excellent properties. For instance, Granitek Ltd, a Leicester-based company, has manufactured precision granite castings for a variety of sectors including machine tools, metrology, inspection, semi-conductor, pre-press, photo-imaging, laser-engraving, medical, dentistry and marine applications with customers in three continents.

Components of PC Aggregates High-hardness mineral aggregates, including quartz, basalt and granite, are typically used; recycled glass is another option. Granite, for example, leaves a jagged edge when broken so it grips the resin better. However, jagged edges can also hinder flow into mould features. In contrast, high-strength, high-purity (99.5% SiO2) quartz aggregate has a rounder shape that improves flow and compaction. Vibratory compaction during the moulding process tightly packs the aggregate together, which boosts part strength. The quartz has a Mohr’s hardness of 8 (diamond = 10) and makes up about 92% of a part by weight.

Resins The PC casting process blends resin, hardener and aggregate in a batch or continuous mixer. A batch mixer is preferred because components can be accurately weighed prior to mixing. The mixture poured into a mould can cure in just a few minutes or perhaps several hours, depending on the resin system and formulation. Curing typically takes place at room temperature, though some resin systems are heat treated for added strength and stability. Features such as tapped holes are cast in place. This a big advantage over machining that depends upon the machine locating the holes properly each time. Casting eliminates the need to inspect whole locations, once established.

Moulds An alternative material such as that used in precision granite castings can have an internal damping factor up to 10 times better than cast iron, up to 3 times better than natural granite and up to 30 times better than steel fabricated structure. It is more cost effective and is unaffected by water, coolants and oils. Besides, it has excellent long-term stability, improved thermal stability, high torsional & dynamic stiffness and excellent noise absorption. Additionally, its low exothermic curing property aids negligible internal stresses, coefficient of expansion, which can vary by changing the constituents, is usually aligned to cast iron. The surface finish of a precision granite casting is as good as the mould surface and, in many instances, the need for painting is not necessary.

Implementation Tests conducted by the University of Dayton in accordance with ASTM E-756-83. Samples measure 2-in square 12-in and are held on one end. A load is applied and removed, and the deflection versus time response is recorded. The applied load is equal for all the four materials, so the initial deflection of the polymer bar is substantially greater than the metallic bars. In practice, the polymer bar would have a much greater section thickness to keep initial deflection on par with the metallic bars.

Say Yes to Polymer Casting Makes cast integral surfaces possible

þ þ

Blends resin, hardener and aggregate in a batch or continuous mixer

Can use moulds of various materials

Conclusion Constructions made of natural granite get distorted in the presence of water in any form. Using precision granite castings, many of these disadvantages can be overcome. PC possesses most of the benefits of conventional materials, and, in some cases, the advantages are enhanced. Although PC incorporates coarser aggregates, they are finer aggregates that fill thin sections better.

Solution Provider Granitek Ltd

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Planetary gears in intensive mixers

ixers are designed to quickly, uniformly and mechanically manipulate a heterogeneous mass of two or more dry or wet materials of varying aggregate sizes into uniformly blended and bonded homogeneous products. In foundries, mixers are required to combine sand with binder ingredients such as, resin and catalyst, in a uniform manner.

The Technology

Benefits to the Environment

The quality of moulding sand depends partly on its manner of preparation. In addition, environmental and economic concerns require the recovery and processing of large quantities of materials. The sand system is therefore of great importance—its central feature being the mixing plants. Planetary gearbox technology allows the mixing blades to rotate in their own axis as well as revolve around the axis of the mixer, thus intensely mixing the sand. This technology is energy-efficient as it consumes much less power.

Energy efficiency Planetary gears, when compared to some larger worm gear units with high reduction ratios that may be only 70% efficient, is a lot more efficient at 98% efficiency per stage.

Better Bentonite consumption Another advantage is high consumption of binder Bentonite. Bentonite is considered the perfect inorganic binder because it can be reused several times (often referred to as ‘a recirculating’ sand system).

Implementation The Wesman Intensive Mixer is designed to efficiently deliver large volumes of high-quality of prepared sand within a short time. The average cycle time is around 90

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seconds. The built-in batch hopper allows preparation of batch prior to emptying the previous batch so that a new batch may be added to the mixer as soon as it is empty.

The name green sand has nothing to do with the colour; it is called so because green sand is used in the molding process in a wet state (akin to green wood). Additionally, ‘green sand’ is a mixture of many minerals in specific quantities.

Distinguishing methods of Sand Casting Green sand method Expendable moulds are made of wet sands that are used to shape it. Green sand comprises clays in varied proportions, but they all strike different balances between mouldability, surface finish and ability of the hot molten metal to degas. Green sand for aluminium typically uses olivine sand (a mixture of forsterite and fayalite, which is made by crushing dunite rock).

The ‘air set’ method This method requires dry sand bonded with materials other than clay, using a fast curing adhesive. The latter may also be referred to as no bake mould casting. When these are used, they are collectively called ‘air set’ sand castings to distinguish them from ‘green sand’ castings.

Green Sand Specifications Green sand is a mixture of:

5–11%

75–85% Silica sand (SiO2), or chromite sand (FeCr2O), or zircon sand (ZrSiO4), or olivine, or staurolite, or graphite

3–5%

Bentonite (clay)

Inert sludge

2–4%

0–1%

Water

Anthracite

Cold box

No bake moulds

Vacuum Molding

This uses organic and inorganic binders that strengthen the mould by chemically adhering to the sand. This type of mould gets its name from not being baked in an oven like other sand mould types. Cold box is more accurate dimensionally than green sand moulds and is more expensive. Thus, it is used only in applications that necessitate its use.

No bake moulds are expendable sand moulds, similar to typical sand moulds, except that they contain a quick-setting liquid resin and catalyst. Rather than being rammed, the moulding sand is poured into the flask and held until the resin solidifies, which occurs at room temperature. This type of moulding also produces a better surface finish than other types of sand moulds. Since no heat is involved, it is called a coldsetting process. Common flask materials that are used include wood, metal and plastic. Common metals cast into no bake moulds are brass, iron ferrous and aluminium alloys. It gets its name from not being baked in an oven like other sand mould types. It is used only in applications that necessitate its use.

This is a variation of the sand casting process for most metals, in which unbonded sand is held in the flask with a vacuum. A heat-softened thin sheet (0.003 to 0.008 in) of plastic film is draped over the pattern and a vacuum is drawn (200–400 mmHg). A special vacuum forming flask is placed over the plastic pattern and is filled with freeflowing sand. The sand is vibrated to compact the sand and a sprue and pouring cup are formed in the cope. Another sheet of plastic is placed over the top of the sand in the flask and vacuum is drawn through the special flask; this hardens and strengthens the unbonded sand. The vacuum is then released on the pattern and the cope is removed. The drag is made in the same way (without the sprue and pouring cup). The cores are set in place and the mould is closed. The molten metal is poured while the cope and drag are still under a vacuum, because the plastic vaporises, but the vacuum keeps the shape of the sand while the metal solidifies. When the metal has solidified, the vacuum is turned off and the sand runs out freely, releasing the casting. setting liquid resin and catalyst. Rather than being rammed, the moulding sand is poured into the flask and held until the resin solidifies, which occurs at room temperature.

Conclusion To ensure proper functioning and efficiency, foundry sand contains certain additives like bentonite, fireclay, pitch, wood flour, etc., which need to be thoroughly mixed. For the moulding sand to be properly conditioned, it ought to not only be discharged from the mixer at the proper temperature but there also has to be proper moisture and additive content in it. Planetary gearboxes achieve this with greater efficiency as they intensely mix the sand and consume much less power.

Innovation Wesman Intensive Mixer

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Drying in foundries

to the Rescue! In foundries, drying is necessary after any wet processes to reduce water content. Drying involves two evaporation techniques—Mechanical Drying and Thermal Drying. While the former removes water particles mechanically bound to the strands/fibres, the latter processes heat and transfers it by different processes such as convection, infrared radiation, direct contact or radio frequency to convert water into steam.

adio frequency is the rate of oscillation in the range of 3 kHz to 300 GHz, which corresponds to the frequency of radio waves, and the alternating currents that carry radio signals. Radio frequency and microwave heating systems have long been established in the industry. Although there are continuous developments in improving existing processes, further R&D in the areas of materials and process specific domains such as sintering, synthesis, polymerisation and other chemical processes aim to improve the heating efficiency.

Say Yes to Radio Frequency Drying Time-saving Energy conservation Uniform and complete Easy to operate and to realise automatic production Improved working conditions 114

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Radio frequency drying involves the removal of water content from fibres, yarns and fabrics through radio frequency. Apart from the textile industry, this process is used in the paper industry, foundries, chemicals, pharmaceutical and ceramic industries.

The Technology Electric currents that oscillate at radio frequencies have special properties not shared by direct current or alternating current of lower frequencies. The energy in a radio frequency current can radiate off a conductor into space as electromagnetic waves (radio waves); this is the basis of radio technology. Radio frequency current does not penetrate deeply into electrical conductors, but flows along their surfaces; this is known as the skin effect. For this reason, when the human body comes in contact with high power radio frequency currents, it can cause superficial but serious burns called radio frequency burns. Radio frequency current can easily ionise air, creating a conductive path through it. This property is exploited by ‘high frequency’ units used in electric arc welding, which use currents at higher frequencies than power distribution uses. Another property is the ability to appear to flow through paths that contain insulating material, like the dielectric insulator of a capacitor. When conducted by an ordinary electric cable, radio frequency current has the tendency to reflect from discontinuities in the cable such as connectors and travel back down the cable toward the source, causing a condition called standing waves, so radio frequency current must be carried by specialised types of cable, viz., transmission line. When the material to be dried is conveyed through radio frequency/microwave field, the water molecules in the material reorient constantly to align with the changing field. This movement generates heat inside water molecules and ensures that the entire mass of water evaporates uniformly without heating the product externally.

Implementation Radio frequency drying technology is used in various foundry processes such as:

 De-waxing of casting moulds  Drying of casting moulds  Hardening of foundry moulds  Regeneration of casting mould waxes  Removing of solid objects from moulds (boards, lids, etc.)  Core drying

Conclusion Electric currents oscillating at radio frequencies have special properties, which do not penetrate deeply into electrical conductors. When radio frequency is used on the material to be dried, the molecules of water in the material align with the changing field. This, in turn, ensures that all the water evaporates without heating the product externally, thereby saving time and conserving energy.

Technology Provider Gujarat-based Twin Engineers provide the e-foundry drying technology (radio frequency and microwave) to not just the foundry industry, but also the pharmaceutical, textiles, power and food processing industries.

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FACTS and

Figures 90% of manufactured goods/products

contain cast components.

Overall, spent foundry sand should be regarded as inert, rather than low-risk waste.

In South Africa, general waste disposal is about `250=$34, per tonne. The Indian economy should make way for such stringent rules. Foundries should start working on

Foundries face issues not only pertaining to cost but also related to

inconsistency in applying the regulations.

secondary uses of spent

foundry sand.

There has been progress on the green manufacturing front; however, legislation still remains the bottleneck. Indian foundries should draw from

international experiences

and learn from their foreign counterparts.

In the UK, foundry waste sand qualifies under the lower rate tax, which is ÂŁ2.50=$4.10, per tonne; India should try to achieve this.

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There is a need for collaboration between foundries, agriculture, environment, construction industries and government departments.

Green technology can include energy and material waste reduction in the manufacturing process, and the use of alternative

manufacturing technologies with

the least impact on human health, the Earth and its natural resources. To become greener, one must find ways to

use energy more efficiently in

Sustainability and the application of green technology means finding smarter ways to use our finite natural resources, both in manufacturing materials and in the energy reserves used to manipulate them.

the complete manufacturing process, and not merely shift energy use up or down in the manufacturing stream.

Foundries need to curb greenhouse gas emissions, address the risk of climate change and simultaneously address the risk of soil and water pollution. Energy saving presents an opportunity for foundries to reduce their carbon footprint. For every 1Kilowatt hour of electric energy saved, 1,03kg of carbon emissions is prevented from entering the environment.

Much of the technology to become greener in the foundry applications presently exists; metal casters have resources to become increasingly sustainable in the near future.

Turning green is costly is nothing but a myth, going green will actually enhance a firmâ&#x20AC;&#x2122;s profitability. Ignorance of the impact of

inspection limitations affects foundries adversely.

Pomposity in not

declaring limitations is also an error that Indian foundries need to look into.

Foundries should develop publicly owned testing facilities where the harmful effects can be measured, valued and solved.

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Marching Towards

Green C

limate change is one of the most serious challenges faced by the world today. Environmental degradation caused by outdated and inefficient technologies and practices has been acknowledged to be one of the primary causes of climate change. As the first step towards promoting sustainable industrial development, UNIDO ICAMT hopes that the Compendium on environmentally friendly manufacturing technologies forms a basis in educating and exposing the Indian industry to the benefits of ‘green’ practices. Although three industry sectors, namely, the machine tool, plastics and foundry sectors, have been addressed through this compendium at this point in time, it is hoped that the movement towards sustainable manufacturing gains momentum across all industry sectors. The scope of sustainable development is extremely varied and with time, UNIDO ICAMT aims to take forward this initiative by conducting seminars and lectures and encouraging factory visits to companies who have taken steps towards ‘green’ manufacturing. It is also extremely important to encourage the government to strategise and formulate legislation that promotes ‘green’ manufacturing. Companies, especially MSMEs, should be provided with economic incentives that encourage them to invest in newer, cleaner technologies, whilst helping them gain a competitive edge in the global market.

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References

Machine Tools 1.1:

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BFW Press Update, Vol 12, No 2, April–June 2011 Energy-using Product Group Analysis Lot 5: Machine tools and related machinery Draft Task 5 Report – Dipl-Ing Karsten Schischke, Fraunhofer Institute for Reliability and Microintegration IZM, Department Environmental and Reliability Engineering, March 2, 2012 Research topics on Green Manufacturing at National Chung Cheng University (CCU) http://aimhieng.ccu.edu.tw/researchprojects/green.php Machine tool lightweight design and advanced control techniques – M Sulitka1, L Novotny1, J Svéda1, P Strakos1, J Hudec1, J Smolik1, P Vlach, Research Center for Manufacturing Technology CTU in Prague, Czech Republic Kovosvit MAS, a. s., Sezimovo Ústí, Czech Republic, 2008

Micro milling in Minimum Quantity Lubrication NP Hung (Texas A&M University), S Kajaria (T3 Energy Services), S Chittipolu (Baker Hughes), S Adera (Georgia Institute of Technology). The 5th International Conference on Micro Manufacturing ICOMM/4M 2010, April 5–8, 2010, Madison, Wisconsin Minimum Quantity Lubrication in Finish Hard Turning – Ronan Autret, Graduate Research Assistant; Steven Y Liang, Professor, George W Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405, 2003 Study of specific energy and friction coefficient in minimum quantity lubrication grinding using oil-based nanolubricants – Parash Kalitaa, Ajay P Malshea, S Arun Kumarb, VG Yoganathb, T Gurumurthy, Elsevier Journal of Manufacturing Processes, April 2012

Feasibility study of the minimum quantity lubrication in high-speed end milling of NAK80 hardened steel by coated carbide tool – YS Liao, HM Lin, YC Chen, 2007 Pulsed laser deposition of nanocoatings on cutting tools – PK Mukund. M. S. Creative Component Report, Mechanical & Aerospace Engineering, Oklahoma State University, Stillwater, OK, 1999 The Possibilities and Limitations of Dry Machining – Dr Neil Canter, Tribology and Lubrication Technology, March 2009

Article: The liquid tool, September–October 2011, EM – The trade manufacture for efficient manufacturing Development of environmentally friendly water-based synthetic metalcutting fluid – Yuzan Yu, Yugao Guo, Lei Wang, Enqi Tang, College of Environment and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300160, China, Modern Applied Science, Vol 4, No 1, January 2010 Henkel sets high standards with Multan 97-10D - The unbelievable cutting fluid, Henkel Press Release 2007

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Article: Chip Compactor Squeezes Out Savings – Kurt Manufacturing Company (Minneapolis, Minnesota), 8/6/2006 Production Machining, Chris Felix, Associate Editor Yuken India Chip Compactor Brochure 2011

1.6

120

Furniture maker Burgess invests in product quality and productivity, www. machinery.co.uk, February 2012 Top quality parts cleaning gives added value, Durr Ecoclean Presse Information, 2010

1.12

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Taegutec India Pvt Ltd website, 2012 Wikipedia – Kaizen, 2012

Plastics 2.1

Formalising proactive maintenance goals – Simon Duff and James Harland, School of Computer Science and Information Technology, RMIT University, DALT 2008 http://www.crane-bel.com/pro-active-maintenance.htm, 2012

Friction stir welding: An environmentally cleaner welding process – V Balasubramanian, Centre for Materials and Joining Research (CEMAJOR), Department of Manufacturing Engineering, Annamalai University, December 2010 http://www.etatechnology.in/ETA-Catalogue.pdf, March 2012 http://www.twi.co.uk/services/technical-information/faqs/process-faqs/faqwhat-is-friction-stir-welding, 2012

1.11

1.5 g

Article: Less is More: Net-Shape Manufacturing – Duane Kari, Technical Sales Support Lead, Top Tool, August 29, 2011 Development and implementation of metals additive manufacturing – Ian D Harris, PhD, Director, AMC EWI, Columbus, OH, January 2012 Experiences using rapid prototyping techniques to manufacture sheet metal forming tools – Prof Dr-Ing DH Mueller and Dipl-Ing H Mueller, BIBA (Bremer Institut fur Betriebstechnik und angewandte Arbeitswissenschaft an der Universitat Bremen) 00SE008 http://www.cmti-india.net, 2012

1.10

1.4 g

How, why, and when to apply electric motors to mobile hydraulic systems – Patrick Berkner, Automation Group – Electromechanical Automation Division, 2101 North Broadway, New Ulm, MN 56073, Parker Hannifin 2008 Global Mobile Sales Meeting & Symposium Whitepaper # 0001 http://www.bluecompetence.net/pages/en/news-n-events/news-cecimo. html, May 2012 Synopsis of energy saving power unit: A case for retro fitment of existing machines –Yuken India Ltd, 2012

1.9

1.3 g

http://www.kladon.in/soundproof.html, 2012 Wikipedia – Noise Pollution, 2012 Wikipedia – Sound Enclosures, 2012 Reducing noise from CNC punch presses, HSE Information Sheet, Engineering Information Sheet No 39, 2012

1.8

1.2 g

Pro-Active Maintenance, Industrial Products Finder, May 2011

1.7

Energy savings and other benefits of AC drive systems for injection molding – Concise Technologies USA, 1999 Fedichem Press Release – Practical Guide to the Plastics Industry prepared by Laborelec for the European Copper Industry, August 2008 Manufacturing Processes Reference, Dell K Allen and Robert H Todd Guide, Pg 240, Industrial Press Inc, January 1994 The use of variable speed drives to retrofit hydraulic injection molding machines – Lawrence Ambs and Michael M Frerker, Industrial Assessment Centre, Department of Mechanical & Industrial Engineering, University of Massachusettes at Amherst, Amherst MA 01003, Energy Engineering, Vol 95, No 1, Pgs 55–76, 1998

Wikipedia – Servo Motor, 2012

2.2

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The Council for Scientific and Industrial Research, South Africa website, 2012 Wikipedia – Stretch Blow Molding, 2012 www.engineershandbook.com, 2004–2006

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2.3

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http://engr.bd.psu.edu/pkoch/plasticdesign/mold_types.htm, 2007 http://www.dsm.com/en_US/html/dep/hotrunnner.htm, 2011 Runner and Gating Design Handbook: The Tools for Successful Injection Molding – John Beaumont, Hanser Verlag, 2008 Wikipedia – Hot Runners, 2012

2.4

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Guide to Energy Efficiency Opportunities in the Canadian Plastics Processing Industry – In collaboration with Canadian Plastics Industry Association, January 2008 http://www.cascadecartsolutions.com/tech/coinjection.htm, 2007 http://www.ides.com/articles/processing/2007/fleck_waterassist.asp, 2007 MDDI Article: Gas assisted injection molding: An innovative medical technology – Michael Hansen, August 2005 Wikipedia – Coinjection molding, 2012 www.battenfeld.ru, Why Water-Assisted Injection Molding? Dipl.-Ing. Wolfgang Roth, Gas and Waster Assisted Injection Molding, September 2007, Warwick University

2.11

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http://www.plasticstoday.com/articles/solar-powered-solution-developedheating-rotational-molds Light Manufacturing LLC, 2012 Wikipedia – Rotomolding, 2012

2.6

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http://www.plastemart.com/upload/Literature/Arboform-Liquid-Woodpulp-based-lignin-strong-non-toxic-alternative-%20to%20petro-basedplastics.asp, 2003 Plastwud information on Anup Technocrat website, 2012 Wikipedia – Wood Plastic Composites, 2012

2.7

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2.9

Chemplast Sanmar Ltd website, 2011 Suez Environment, Degremont Technologies, 2012 www.evaporator.com, 2011 August 24, 2009 – Using renewable (bio) content & biodegradability to design & synthesize ‘green’ products. Ramani Narayan Michigan State University, narayan@msu.edu P&G to introduce new sugar-cane derived plastic packaging, Packaging Digest, 2010 Plastic News – The Official Organ of the All India Plastics Manufacturers’ Association, Estd. 1945, October 2011, ‘Renewably Sourced Bioplastic by Dr Donald Rosato’, Pg 41 Production of Bio-ethanol based Polyethylene, Pre-Report University of Illinois at Chicago, Chemical Engineering, Pravina Mokashi, January 2010 Sumpoorna Global Markets and Economics Research, Rising Star – India Glycols, April 20, 2012, by Nitesh Aggarwala and Ishu Mann

British Plastics Federation http://www.bpf.co.uk/sustainability/operation_ Clean_Sweep.aspx, 2009 Plastic News – The Official Organ of the All India Plastics Manufacturers’ Association, Estd. 1945, May 2012

2.15

Styrofoam recycling, CIPET Times, July–November 2008, Pgs 24–26 Almitra Patel Supreme Court Committee on Solid Waste Management, Bangalore, 2010 Amjad Khan, Gangadhar Murali Mohan and Vinay Raykar, Project Report

A custom market research study reviewing the potential for plastic railroad ties in Canada – CIC Innovations Consultants Inc, prepared on behalf of the Environmental and Plastics Industry Council, Ontario, Canada, April 1, 2003 M/W Budgets to climb in 2008. Railway Track & Structures (New York, New York: Simmons-Boardman Publishing Company), Vol 104, No 1, Pgs 18–25, January 2008. ISSN 0033-9016. OCLC 1763403. Retrieved December 23, 2011. Use of recycled material in composite sleepers – SK Jagasia, VP Composite Product, presentation by M/s Patil Group of Industries. The Asian Plastic Recycle and Waste Management Conference at Pragati Maiden, New Delhi, February 2009, Plastindia Foundation

2.14

2.10 g

ACC emission monitoring result: Co-processing trial of plastic waste, ACC Kymore Cement Works 2008 – Jean Pierre Degre, Ulhas Parlikar, Milind Murumkar, Moumita Chakraborty, Ramesh Suri, KM Gupta Co-processing of waste in cement kiln: Experience of Grasim Industries Limited – Dr KV Reddy, Hyderabad, 2010 Environmental benefits of using alternate fuels in cement production: A life-cycle approach, CEMBUREAU – The European Cement Association, 1999

2.13

2.8

ARS Automat 2012 Process of de-lamination of multi-layer laminated packaging industrial refuse (US 2004/0054018) – Ashutosh Mukhopadhyay

2.12

2.5 g

prepared under the guidance of R Suresh and H Kumar, Department of Chemical Engineering, RV College of Engineering, Bangalore, 1999 http://bangalore.citizenmatters.in/articles/view/239-plastic-roads, 2008 Ministry of Road Transport & Highways – Manual for construction and supervision of bituminous works, New Delhi, November 2001 Plastic News – The Official Organ of the All India Plastics Manufacturers’ Association, Estd. 1945, ‘The Use of Waste Plastic in Construction of Flexible Pavement’ Vol 48, No 11, Pgs 42–45, November 2011 Sri Ram Institute for Industrial Research, Plastics Processing & Environmental Aspects, New Delhi, February 7, 2010 Use of waste plastics in cement concrete pavement – BV Kiran Kumar and P Prakash, Dayanand Sagar College of Engineering, Bangalore, 2005 Utilization of waste plastic bags in bituminous mix for improved performance of roads, Center for Transportation Engineering, Bangalore University, April 2002 Utilization of waste plastics for flexible pavement – R Vasudevan, Indian Highways (Indian Road Congress), Vol 34, No 7, July 2006

Shop floor scheduling with simulation based proactive decision support – AK Gupta, AI Sivakumar, S Sarawgi. Simulation Conference, 2002. Proceedings of the Winter, Vol 2, Pgs 1897–1902 The Logility Executive White Paper ‘Reducing Energy Costs for Plastic Manufacturers – The Role of Constraint Based Planning and Scheduling’, 2007

2.16

Guide to Energy Efficiency Opportunities in the Canadian Plastics Processing Industry – In collaboration with Canadian Plastics Industry

121

g g

Association, January 2008 http://www.artcorp.com/prototyping_sporting_goods.html, 2008 http://www.prlog.org/10086609-prototype-advantages-and-rapidprototyping-benefits.html, 2008 Wikipedia – Rapid Prototyping, Stereolithography, SLS, BMP, 2012

Foundry

3.6

g g

3.7

3.1

g g

Cupola Design, Operation and Control, BCIRA, 1979 Savings from divided blast cupola: A case study of successful implementation at a foundry unit in Rajkot, MH Patel Shining Founders and Engineers Rajkot – Prosanto Pal and Abhishek Nath, TERI 2009 Towards cleaner technologies: A process story in small-scale foundries – Prosanto Pal, TERI 2006

3.2

g g g

g g

g g g

Duplexing with the cokeless cupola, RT Taft, 1995 The modern cokeless cupola, RT Taft, 1993 Why the cokeless, RT Taft, 1992 www.wesman.com/about-us/global-technology-partners/cokeless-cupolaltd.html, 2012

Foundry Technology – Peter Beely, Butterworth-Heinemann, 2010 Induction furnace: A review – Vivek R Gandhewar, Satish V Bansod, Atul B Borade, International Journal of Engineering and Technology, Vol 3, No 4, Pgs 277–284, 2011 Improvement in energy efficiency of melting furnace: A case study – Dr DS Pande, Foundry Tata Motors Ltd, Jamshedpur, 2004 Melting automation using medium frequency induction furnace – Arimichi Morita and Toshiyuki Kano, Fuji Electric Thermo Systems Co, May 2008 Need for energy efficiency and promotion of cleaner production in the foundry sector in India – R Rodramoorthy, VS Puranik, C Viswanathan, Sivanappan Kumar, Proceeding of the International Conference on Environmental Management in Metallurgical Industries, Edited by RC Gupta, December 2000 The Energy Center, Wisconsin, The Foundry Industry: Review of Process Energy Use, Markets and Information Resources, May 1997, Report 155-1

3.5

g g

122

AutoCAST: Casting design assistant – B Ravi, Metal Casting Technologies, Vol 52, No 3, Pgs 84–86, 2006 Casting method optimization driven by simulation – B Ravi, Metals and Minerals Review, Vol 34, No 3, Pgs 39–43, 2008

3.10

Fettling: The most ignored operation in foundries – Prashant Mestry, Mahindra & Mahindra, Automotive Division, published on Foundry Informatics Centre website, IIF Delhi, 2007 Hazards associated with foundry processes: Fettling – noise hazards HSE Information Sheet, March 2012

3.11

3.4 g

SEDA 2002, Energy and Greenhouse Management Toolkit Variable Speed Compressors: Raising the Bar for Variable Speed Performance, Carrier Corporation, Syracuse, New York, 2005 Wikipedia – Screw Compressors, 2012 www.delhitransco.gov.in/energyefficiency/ec%20award%202006/ Questionnaire%20Large&Med%20Industry2006/05-AnnexureC.pdf

3.9

3.3 g

Gases formed from furan binding agents – M Virtamo and A Tossavainen, Scandinavian Journal of Work, Environment & Health, 1976; 2 Suppl 1, Pgs 50–53. doi:10.5271/sjweh.2832 HA International LLC website, 2007–2012 www.fosecomet.com, 2005

3.8

2nd International Cupola Conference, Trier 18./19.03.2004. Recent trends in the usage of recovered heat energy arising from cupola melting practice in Japan with an example of latest foundry plant – Y Murata, K Tachiiti, T Ishino, T Okabe Towards cleaner technologies: A process story in small-scale foundries – Prosanto Pal, TERI 2006 Wikipedia – Heat Exchanger Definition, 2012 www.naniwaroki.co.jp/en/cupola_01.html, 2012 www.substech.com, 2011

IC Engineering Solutions Florida 2008, www.icmech.com JEA, August 2005, Best Management Practice and Guidance Manual for Cooling Towers The benefits of VFDs on cooling towers – Joe Koepke, Yaskawa Electric America Inc, HPAC Engineering, 2009

g g

Environmental-friendly durable concrete made with recycled materials for sustainable concrete construction, 2005 – TR Naik, UWM Center for Byproduct Utilisation, University of Wisconsin, and G Moriconi, Materials Science and Technology, Materials and Environment Engineering and Physics, Marche Polytechnical University, Italy Foundry Sands Recycling, EPA, United States Environmental Protection Agency/ April 2007 EPA530-F-07-018 The US Dept of Agriculture (USDA) www.ars.usda.gov, 2012 www.articles.economictimes.indiatimes.com/2012-02-24/ news/31095305_1_foundry-units-productivity-sand www.roionline.org/ongoing_projects.htm

3.12

g g

Epoxy granite: A structural material for precision machines – P McKeown and G Morgan, Precision Engineering, Vol 1, Pg 227, 1979. doi:10.1016/0141-6359(79)90104-1. Wikipedia – Epoxy granite Polymer castings take on metals – Terry Capuano, Machine Design, 2004

3.13 Energy Conservation Opportunities: Foundry Industry, CEE and IIF study by AK Anand, Director, The Indian Institute of Foundrymen and Prabhjot Sondhi, National Coordinator, UNDP-GEF, Small Grants Program, CEE, New Delhi, 2008 Impact of cooling tower blade modification on energy consumption – P Gupta, Mechanical Engineer, E Nuclear Science Centre, New Delhi, Air Conditioning and Refrigeration Journal, 2001 www.cooldeckin.com/FRP%20Fans.htm, 1999–2003 www.energymanagertraining.com/Documents/success/casestudy26.pdf, 2009

g g g

Brevini Riduttori Press Release 2003 ‘Planetary Gear Technology’ Foundry Technology – Peter Beely, Butterworth-Heinemann, 2010 www.wesman.com/products/foundry-equipment/mixers-and-mullers.html, 2012

3.14

g g

Radio frequency and microwave heating: A perspective for the millennium – Dr Ricky Metaxas, University of Cambridge, Power Engineering Journal, April 2000, Pgs 51–60 www.electronicdrying.com/application_foundry.php, 2011 www.pscrfheat.com/radio-frequency-basics, 2012