SA Mechanical Engineer July 2019 by Promech Publishing

S MECHANICAL A ENGINEER July 2019

Publication of the SA Institution of Mechanical Engineering, incorporating News of Associate Organisations

INVESTIGATING THE ENGINE MURDERERS

SMOKE CONTROL A MUST WHEN FIGHTING FIRES

FAG CONCEPT 2

LUBRICATOR

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VOL 69 July 2019

AN ENGINEER’S VIEW

The Importance of Engineers in Supply Chain

enerally, one might think of an engineer as wearing a hard hat (a white one) and safety glasses, somewhere in a plant or construction site, carrying a set of drawings, trying to solve challenging problems or overseeing a project. The many fields of mechanical engineering are so vast that the important or even critical roles engineers play in ‘less technical’ environments are mostly misunderstood and overlooked. The role of engineers in supply chain and more specifically in strategic sourcing is a typical example. Supply chain offers engineers strategic roles with long term benefits to the employer as opposed to the role of operations and / or maintenance engineers whose primary responsibility is to complete projects or start the plant up as soon as possible after routine maintenance. As an engineering professional working in a design environment, awareness of engineering possibilities in supply chain was unknown. Many companies still don’t realise the real consequences of strategic decisions taken (or not taken) in supply chain, including its effects on operations and vice versa. The importance of having strong engineering individuals working in supply chain to make strategic technical decisions suddenly became clear as this would form the basis to ultimately reduce total cost of ownership (TCO) and improve plant availability without operations realising potential changes to past ‘modus-operandi’. The time spent in a supply chain environment highlighted important responsibilities of engineers which include: obtaining a holistic view of mechanical goods and services within the local (and if applicable international) markets to ensure best standards and practices for procurement, establishing a common strategic direction for dealing with key suppliers and stakeholders, optimising and standardising procurement opportunities, management and optimisation of internal approved vendors/ manufacturers to ensure procurement that meets the relevant health & safety standards as well as local and/or international engineering standards and specifications. To manage this effectively, a diligent engineering

thought process is required to understand the technical requirements Niekie Swanepoel, MSAIMechE of internal business processes. Further support in the form of broad knowledge and background of various, different engineering standards and specifications supports regular audits on suppliers to verify compliance. One often hears of procurement challenges such as the recent trains that were procured to the wrong specifications. One can’t then help wonder if there was any engineering involvement in the supply chain and possible technical standardisation processes.

Although the role of engineers in supply chain might be considered ‘less technical’ than in the mechanical engineering environment, it certainly is a critical and much needed role

From a maintenance point of view standardising on specific brands of equipment (e.g. pumps, valves, filters etc.) is in most cases a good approach. This in turn brings benefits such as minimum / critical spares coordination, stock holding benefits and strategies that supports plant availability. On the other hand, standardisation can reduce competitiveness in the market and needs to be managed carefully, as this could make the plant vulnerable by being too reliant on one or two suppliers. A critical challenge engineers in strategic sourcing face is to find that balance between ensuring security of supply, understanding stakeholder requirements and expectations, effectively managing total cost of ownership and technical and legal compliance through correct supply chain practices and procedures. Although the role of engineers in supply chain might be considered ‘less technical’ than in the mechanical engineering environment, it certainly is a critical and much needed role with responsibilities and deliverables that can achieve huge cost savings benefits for any company through transparent and diligent sourcing strategies. Niekie Swanepoel MSAIMechE

THE SOUTH AFRICAN MECHANICAL ENGINEER

VOL 69

July 2019

S MECHANICAL A ENGINEER July 2019

Publication of the SA Institution of Mechanical Engineering, incorporating News of Associate Organisations

S MECHANICAL A ENGINEER July 2019 VOLUME 69

Contents INVESTIGATING THE ENGINE MURDERERS

SMOKE CONTROL A MUST WHEN FIGHTING FIRES

On the Cover

Invincible Valves Tel: (011) 822-1777 Email: pamdp@invalve.co.za www.invalve.co.za

Technology

25 Dealing with waste

Health and Safety

Getting Your Factory Smart

Cover Story 8

Connections Move Products

26 Combining Sprinklers With Smoke Control a Must

SA Institute of Tribology

Mechanical Pathology

10 Dirt-Tolerant, Oil-Free, Water- Hydraulics

28 The Engine Killers

Valves

Automation 13 Safely Guiding Vehicles From A to B

33 Controlling The Flow

Maintenance

Regulars

15 Keeping Trains Rolling

3 An Engineer’s View 35 Market Forum 38 On the Move

Safety 19 Diesel Pumps Ready to Tackle Fires

Environment 23 Tackling Water Loss the Clever way

All rights reserved. No editorial matter published in “SA Mechanical Engineer” may be reproduced in any form or language without written permission of the publishers. While every effort is made to ensure accurate reproduction, the editor, authors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any consequences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

Produced by: PROMECH PUBLISHING, P O Box 373, Pinegowrie, 2123, Republic of South Africa Tel: (011) 781-1401, Fax: (011) 781-1403 Email: samecheng@promech.co.za, www.promech.co.za Managing Editor Susan Custers Editorial Contributors Liesl Venter/Patricia Holburn Advertising Sales: Louise Cresswell Cell: 071 886 1263 DTP: Sanette Badenhorst Circulation: Netta Janse van Rensburg Subscriptions Please email us at accounts@promech.co.za if you wish to subscribe to “SA Mechanical Engineer” at R550,00 (excl postage and VAT) per year; R1 380,00 per year for Africa/ Overseas. Disclaimer

PROMECH Publishing and The South African Institution of Mechanical Engineering as well as any other body do not take responsibility for the opinions expressed by individuals.

Printed by: Typo Colour Printing, Tel: (011) 402-3468/9 FSC (Forestry Stewardship Accreditation)

Official Publication of THE SA INSTITUTION OF MECHANICAL ENGINEERING and endorsed by:             

CONSULTING ENGINEERS OF SA CORROSION INSTITUTE OF SA INSTITUTE FOR CERTIFICATED MECHANICAL AND ELECTRICAL ENGINEERS NATIONAL SOCIETY OF BLACK ENGINEERS NUCLEAR INSTITUTE SA ASSOCIATION FOR ENERGY EFFICIENCY SA CAPITAL EQUIPMENT EXPORT COUNCIL SA INSTITUTE FOR NON-DESTRUCTIVE TESTING SA INSTITUTE OF TRIBOLOGY SA PLASTIC PIPE MANUFACTURERS ASSOCIATION SA PUMP MANUFACTURERS ASSOCIATION SA VALVE AND ACTUATORS MANUFACTURERS ASSOCIATION VALVE & ACTUATOR MANUFACTURERS CLUSTER OF South Africa

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SA INSTITUTION OF MECHANICAL ENGINEERING

Council 2018 - 2020

Company Affiliates

Office Bearers

President......................................................Prof D Blaine (Debby) Vice President....................................... H Makwarela (Hangwani) National Treasurer.............................Prof JL van Niekerk (Wikus)

Branch Chairpersons

Amoricom Autodesk as represented by Worldsview Technologies

Central ............................................................... A Celliers (Alicia) Eastern Cape........................................... G van den Berg (Gideon) KwaZulu-Natal ........................................ Dr J Padayachee (Jared) Mpumalanga Highveld .....................................N Lecordier (Noel) Vaal.............................................................. N Swanepoel (Niekie) Western Cape ............................................... Dr M Venter (Martin)

Babcock Ntuthuko Engineering Pty Ltd

Procedures.......................................................... SZ Hrabar (Steve) Communications and Marketing..................G Bartholomew (Bart) TBC...........................................................MAE Black (Malcolm) TBC..............................................................HG Bosman (Tertius)

Portfolios:

Chief Executive Officer..................... Vaughan Rimbault National Office Manager................ Anisa Nanabhay PO Box 511, Bruma, 2026 Tel: (011) 615-5660 Email: info@saimeche.org.za Website: www.saimeche.org.za Membership Email: membership@saimeche.org.za

Eskom Rotek Industries SOC Ltd

Osborn Engineered Products SA (Pty) Ltd Plant Design & Project Services (Pty) Limited (PDPS) PPS Insurance Co Limited Proconics

Esteq Group (Pty) Ltd

Redheads Engineering Services (Pty Ltd)

Exxaro Resources (Pty) Ltd

S.A.M.E Water (Pty) Ltd

Festo (Pty) Ltd

SA Power Services (Pty) Ltd

Fluor SA (Pty) Ltd

Sasol Technology (Pty) Ltd

Kelvion Systems (Pty) Ltd

Siemens (Pty) Ltd

Hatch Africa (Pty) Ltd

Spirax Sarco (Pty) Ltd

Howden Power (a div of Howden Africa)

Tenova Mining and Minerals SA

Howden Projects (a div of James Howden)

Thyssenkrupp Engineering (Pty) Ltd

MBE Minerals (SA) (Pty) Ltd

Vital Engineering (Pty) Ltd

Megchem

Weir Minerals Africa

Mod-U-Flow CC

much more than just a pump in a

BOX

complete pumping solutions Email. info@pumptechnology.co.za 6

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TECHNOLOGY

Getting Your FACTORY Smart As African manufacturers begin to upgrade their operations, mapping out an incremental approach is essential. Smart factories, digitisation, and the Internet of Things (IoT) are all hot topics in the manufacturing sector.

“

With a practical, incremental plan of action, including options with minimal disruption and low-risk, even those who have been reluctant to embrace next-generation technology can get started,” advises Adriaan Rossouw, a Director at EOH Infor Services.

With complete supply chain visibility and real time insights, organisations can not only have better control of their product, but also provide control to the customer Following the five steps

There are five steps to embracing the digitisation journey, easing in, determine the goals, addressing funding issues, prioritising actions and delineating the size of the move. To ease in, it’s important to realise that equipment can be modernised, processes upgraded and new technologies adopted gradually, all while controlling risk. “With a gradual approach, manufacturers can turn to edge applications, hybrid solutions and a phased roll-out to build confidence and gain buy-in from the various teams,” says Adriaan.

Adriaan Rossouw

Now it’s time to determine the goals for the investment and tactics to get there. Most digital technologies, like IoT, are not out-of-the-box solutions.

A customised approach is critical. Setting a very well-defined plan with measurable milestones will help eliminate project ambiguity. Focus on building a plan that is practical, doable, and cost-effective.

Look after the money

Funding issues must be hashed out at the onset. If the business isn’t ready for a huge investment in IT solutions, start small with a subscription-based cloud deployment. Building the business case to prioritise steps is important. There are some prerequisites that are must-have basics for modernising operations. These are the foundations for growth. The size of the move often guides the strategy. Moving to a server model is a good example of this. Offering the product as a service or outcome-based solution, rather than selling the product, is gaining traction in some industries (especially ones where the traditional product is high-value, like cranes, tractors and road building equipment). “This often requires new strategic thinking and the integration of unfamiliar technologies,” says Adriaan. Deciding whether to increase services or scale can be a difficult decision. However, prioritising the customer is a better approach. “With complete supply chain visibility and real time insights, organisations can not only have better control of their product, but also provide control to the customer, allowing them to track progress in real time,” he adds. “For customers seeking specialised customisation, companies can leverage existing data by applying smart analytics and AI to determine and predict customer needs on an individual basis,” concludes Adriaan. EOH Infor Services, Adriaan Rossouw Tel: (011) 607-8299 info@eohinforservices.com, www.eohinforservices.com

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COVER STORY

Connections Move Products It’s no accident when business ticks along – it’s deliberate, ongoing behind the scenes work that keeps people connecting and products moving. “SA Mechanical Engineer” caught up with Pam du Plessis, MD of Invincible Valves in Germiston, to find out what’s on her mind and how Invincible Valves makes the connections that keeps business ticking over in 2019.

ust back from their first stand at LME, Pam and the team are gearing up for Kite at the end of July, an exhibition in KZN followed by Electra Mining Botswana, and many other smaller exhibitions on mines around the country.

students, for example, which is different from our other bags,” Pam explains.

The experience at Electra Mining was, in Pam’s words, “fabulous.”

Specialists match suppliers and providers

“It was the first time we had done the show and I have signed up for the next show in two years,” she says.

We’ve learnt to pack different bags for the different visitors so we have a bag for students, for example, which is different to our other bags Shows and exhibitions aren’t everyone’s favourite, but for Pam and Invincible Valves they offer good value.

And there are other benefits such as interviews on the platinum gold radio station at the exhibition, which spreads the word really well. A good show experience is about getting the right feet to your stand. Pam has found that two exhibition companies they work with have got this right. “Organisers will look for suppliers and match suppliers with providers. They know what people are looking for and will go and find it, and make sure it is at the exhibition.” Invincible Valves attends many other smaller exhibitions on mines around the country where Pam says you get great value because you meet the people who are using the products.

“People often say it is expensive, but if you break it down it is worth it. We purchased our stand, so only incur that cost once, and you get five days with a huge volume of traffic.”

“People on the mines receive personal invites and you get to meet the fitters, shift leaders, etc. They know what they need and will often see something they like and tell the decision maker to come and take a look,” she says.

From many years of experience, they’ve also learned to control costs. “We’ve learnt to pack different bags for the different visitors so we have a bag for

Building networks and creating contacts shows results. Pam shares the example of their agency in Nigeria, which although very small is starting

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to make contacts through their presence at expos. Good for business in west Africa, where Pam says the business is doing very well.

Localisation

Another key ingredient in making exhibitions work is where local manufacturers and suppliers are showcased. “One of the first shows we did was where there were a few local suppliers – about two rows, and the rest were exporters. That does not interest me. And - we should be looking at localisation.” Localisation has been on the cards for many years, so for something that should by now be automatic, it remains more an aspiration than a reality. Pam says you cannot just say localisation and expect it will happen because so much else affects local production. “It’s all good to say we can make things in SA, which we can, but we are not the most efficient when it comes to labour, power and water supply. These things all impact our business. So if labour goes on strike my business shuts down completely. The powers that be need to understand that localisation can only be achieved when these things are dealt with.” That makes for unnecessary difficult business conditions, as do the latest BEE codes with bursary funding requirements. Pam has always emphasised the importance of education and offers numerous training programmes. But the requirement of offering bursaries in the new code means the business has to spend more. “We’re going to have to spend money outside our

businesses. I agree we need to educate, but why are we training at such a high level? I would rather take 20 people, put them through a six month training course – say to become plumbers and electricians, and then in six months they could start their own businesses. That’s creating employment. When you only focus on university education you leave too many people behind.” There’s another question Pam has of the code: “Why are the male percentages higher than the female percentages? What happened to uplifting women?”

A key ingredient in making exhibitions work is where local manufacturers and suppliers are showcased Valid comments from a women who has won numerous awards in the past and recently won the Africa’s Most Influential Women in Business and Government engineering and manufacturing where she was one of 72 finalists – great encouragement for women in the industry. “72! Wow – that was impressive. I was blown away by the fact that we have so many nominees in Africa. Girls are putting their foot down.” It inspired her to think of a network for women in Africa in mining and manufacturing. We might be in a slow economy with a lot of policy questions, but the need to connect never goes away. And as Invincible Valves has found, making connections is good business practice. Invincible Valves Pam du Plessis Tel: (011) 822-1777 Email: pamdp@invalve.co.za www.invalve.co.za

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TRIBOLOGY

Dirt-Tolerant, Oil-Free, WaterHydraulics A new approach to water hydraulics has been developed and proven in the South African mining industry over the last three decades.

it also has some ‘not so favourable traits’ which need to be managed.

typical suite of water power tools used in mines is shown in figure 1. These tools are energised by a power pack, i.e a pump unit that generates pressure, which supplies high-pressure water to a small-bore pipe distribution network of hydraulic hoses.

Water has a low viscosity and poor lubricity. Hydrodynamic films are correspondingly thinner, and less able to support loads compared with oil films. It also cavitates more easily than oil, freezes and boils within a relatively narrow temperature range and fast moving jets can erode steel surfaces. Furthermore, it corrodes carbon steel and cast iron.

Different solutions to oil hydraulics

What makes water-hydraulics possible?

A different design approach has made this possible. This alternative design approach avoids supporting loads on thin hydrodynamic films, avoids metalon-metal sliding counter-surfaces and avoids small clearance gaps. Essentially, this means applying different tribological solutions to those used in conventional oil hydraulics.

The design approaches that have made waterhydraulics possible include supporting loads on polymer-on-steel counter-surfaces, minimising erosive energy by reducing fluid velocities in small steps and directing fluid jets away from surfaces into the body of the fluid, where the energy can be harmlessly dissipated.

While water is in many ways, a ‘darling fluid’, being well-understood, inexpensive, readily available, non-toxic, non-flammable, non-contaminating, having a high bulk modulus and low air solubility,

In addition, when using water-hydraulics, cavitation or the damaging effect of imploding micro vapour bubbles when fluid pressures increase needs to be controlled by managing flow areas and velocities so that Bernoulli pressure changes are limited. Conical or flat seated poppet valves with large contact areas need to be employed instead of sharp-edged ‘line-contact’ spool valves and stainless steels that

Given that the cost of electrical energy continues to rise faster than inflation, energy efficiency is important for sustainability of both business and the environment.

Figure 1 Typical suite of water power tools

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are corrosion resistant need to used. Lastly, water cooling and lubricating elastomeric seals and polymer load-supporting bearings that operate under very thin film or marginal asperity-contact conditions, rather than full-film hydrodynamic lubrication conditions are a must. Importantly, these approaches allow metal-to-metal clearances to be increased from the few microns common in oil hydraulics, to hundreds of microns in this type of water hydraulic equipment. Increasing clearances by a factor of 10 or more improves dirt tolerance dramatically. Dirt particles, in sizes and numbers that would rapidly destroy oil hydraulic equipment, can therefore be tolerated. While contaminating particles are always undesirable, in mine service water they cannot be avoided, because it is not practical or cost-effective to finely filter the water to the equivalent of oil cleanliness standards, the best that can be done is to remove the bigger particles (>50 micron).

Best suited for mines

staple-lock hydraulic hoses. Combined isolation valves and hydraulic fuses protect the system from potentially hazardous run-away flows should a hose burst. These, like an electrical circuit breaker, trip and isolate the supply from the burst in a fraction of a second and prevent the uncontrolled release of energy. These valves have contributed to the good safety record of water hydraulics over the last 30 years. From a tribology and design viewpoint, rotary percussive drills and drifters are the most challenging, but after 30 years of development, designs are now mature. Typically, water drills are 2 to 3 times more powerful than their compressed air counterparts, for less weight and more metres drilled between repairs.

While water hydraulics is unlikely to replace conventional oil hydraulics, it has a place in applications where clean and convenient hydraulic power from a single hose or pipe has benefit.

Unlike water, most oil hydraulic fluids contain many additives like anti-oxidants, extreme pressure or friction-reducing compounds, viscosity modifiers, anti-foaming chemicals and corrosion inhibitors.

Given that the cost of electrical energy continues to rise faster than inflation as shown in figure 2, energy efficiency is important for sustainability of both business and the environment.

Fire-resistant, oil-water emulsion hydraulic fluids are used in coal mines and steelworks, where the flammability of conventional oil hydraulic fluids precludes the use of conventional oil hydraulic fluid. However, the design lineage of these systems largely follows that of traditional oil hydraulics and is therefore correspondingly more dirt sensitive.

Water hydraulic solutions offer a 10-times or more improvement in efficiency compared with compressed air and can eliminate the massive leak-driven wastage that attends large, continuously pressurized, networks of compressed air and mine service water pipes. Water hydraulic systems also eliminate the contamination of the working environment from spent or leaked oil that may occur with conventional oil hydraulics.

Both oil-water emulsion and 100% water hydraulic systems generally use positive displacement, ceramic plunger, reciprocating pumps. Once again, the tribology issues relating to thin film hydrodynamic thrust bearings and erosion of sliding plate valves reduce the life of conventional gear, or swash plate pumps where water is involved. Water hydraulic systems can be ‘open circuit’ or ‘partially open circuit’ meaning than none or only some of the fluids need be recirculated back to the pump inlet. By comparison, virtually all oil hydraulic systems are ‘closed loop’. Open systems are desirable in mines as water is needed to flush out chippings from the hole when drilling and to suppress dust. Furthermore, they permit the use of jet devices that discharge into the working environment.

While water hydraulics is unlikely to replace conventional oil hydraulics, it has a place in applications where clean and convenient hydraulic power from a single hose or pipe has benefit. Peter Fraser Hydro Power Equipment (Pty) Ltd peter@hpesa.com

High-pressure water can be viewed as an ‘energy delivery medium’, like electricity, compressed air or pressurized oil. It is well suited to mining, especially in narrow and dipping stopes where pressure is delivered in pipes from a remote pump or pressure source, thereby allowing the primemover to be located away from the confined and dirty stope environment. Furthermore, ‘high-voltage water’ can deliver significant power in small-bore pipes and hoses.

Used in power tools

Water power tools are connected using standard

Figure 2 – Electrical energy costs, Gauteng petrol price and CPI trends

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LIGHTER, MORE FLEXIBLE AND EASIER-TO-HANDLE Introducing MXT™, Gates’ innovative hydraulics solution designed specifically to address evolving application challenges: lower equipment weight, easier hose assembly and less assembly time. Made with high-performance reinforcement and a robust, abrasion-resistant rubber cover, MXT™ is a universally applicable premium product offering performance exceeding industry standards. It meets the needs of diversified applications, which allows you to consolidate inventory while giving you exactly the hose you need, when you need it.

MXT™

THE NEW GENERATION OF PREMIUM HYDRAULICS

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AUTOMATION

The outdoorScan3 works with unrivalled safety and reliability whatever the weather

Safely Guiding Vehicles From A To B Sick Automation has launched a safety laser scanner certified to IEC 62998 for use in outdoor applications. The outdoorScan3 allows automated guided vehicle systems to navigate through outdoor industrial environments. With its outdoor safeHDDM scanning technology, it works safely and reliably whatever the weather, closing the gap in the automation of industrial processes.

afety laser scanners enable humans and machines to work together in industrial environments by reliably protecting stationary and mobile applications. With the outdoorScan3, certified safety sensor technology can be reliably used outside of production halls for the first time. This opens up huge potential for automating and increasing the efficiency of intralogistics production processes and brings the vision of a self-managed value chain in the spirit of Industry 4.0 one step closer to reality.

Safety laser scanners enable humans and machines to work together in industrial environments by reliably protecting stationary and mobile applications Unique functionality in all weather conditions

The outdoorScan3 is characterised by an exceptional ruggedness when subjected to sunlight, rain, snow, and fog. Outdoor safeHDDM scanning technology means the laser scanner can work without errors when exposed to sunlight with an illumination intensity of up to 40 000lux. The software algorithm

detects rain and snow, easily filtering out these environmental influences.

Automated outdoor processes

Automated guided vehicle systems facilitate a flexible and productive material flow and will be a key technology in the automation concepts of the future. But currently these systems can only be used in a working environment that is shared by humans and machines. With the outdoorScan3, automated guided vehicle systems will be able to perform tasks outdoors with no physical partitions whatsoever and without having to significantly lower their speed.

Versatile range of applications

Performance tested under real world conditions, the scanner is already used on passenger boarding bridges as well as for protecting and navigating automated guided vehicle systems. Sick Automation Southern Africa Stephen Eltze Tel: (010) 060-0550 Email: Stephen.eltze@sickautomation.co.za www.sickautomation.co.za

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South Africa’s perfect blend of ingredients provides the ideal backdrop for this international Congress: adventure, wildlife, magnificent scenery, rich cultural diversity, and efficient infrastructure. Few countries in the world can match the fun, beauty and excitement you will find in South Africa. At the foot of the vast continent of Africa is Cape Town, host city of the FIATA World Congress 2019, also known as South Africa’s “Mother City”. Cape Town is set in a dramatic landscape of exquisite natural beauty, nestled between the majestic Table Mountain and the sea, and is widely regarded as one of the most beautiful cities in the world.

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VOL 69 July 2019

EARLY ACCOMMODATION SPECIAL Choose from among some of Cape Town’s most convenient Congress hotels, with prices and star-ratings to suit all budgets. Participants that book and pay in full before 30 April 2019 will beneﬁt from special discounted accommodation rates.

MAINTENANCE

Keeping Trains Rolling In the rail industry, time is valuable currency. SKF’s latest digital innovation is proven to extend maintenance levels and keep rolling stock rolling as much as possible.

ondition-based maintenance (CBM), which involves measuring and monitoring parameters such as vibration and temperature to spot anomalies at an early stage has been applied for a long time in many industries. The monitoring aspect is commonly known as conditioning monitoring. Historically, the rail industry’s maintenance regime is to service trains on a time or mileage basis. Though this approach has been used successfully for many years, it does not take into account if parts actually need replacing. Inspection can only take place when trains aren’t running, and maintenance actions require rolling stock to be taken out of service, or lines to be closed for extended periods.

Maintenance costs remain one of the biggest concerns for the train industry, due to aging fleets and the increasing need for train availability As such, maintenance costs remain one of the biggest concerns for the industry.

Early warning

Adoption of CBM is steadily growing thanks to significant innovations and the availability of technology. Digitalisation is making a major difference towards how maintenance is executed and can enable the customer to extend maintenance intervals. This can have beneficial effects on, for example, train availability. The less time rolling stock spends in maintenance, the more time it can spend carrying passengers or cargo. It can also help with reduc-

ing lifecycle costs and inventory management of spare parts, due to the early warnings provided by condition monitoring of any risks and possibilities of incidents. SKF combined CBM with its knowledge of bearings and other components and developed an entirely rail-focused version of its Multilog IMx platform.

The next step in train digitalisation

Multilog IMx-Rail is a multi-channel, on-line condition monitoring system based on new rail approved components. It is the next step in train digitalisation, allowing operators to implement condition-based maintenance that can help achieve goals such as TCO reduction, higher availability, the avoidance of unplanned stoppages and longer maintenance intervals.

Proven on the tracks

Multilog IMx-Rail is already demonstrating its capabilities in the field. To provide a sense of how the system typically works, on a standard commercial train, for example, the self-contained package of sensors and electronics is mounted onto one of the train’s bogies, under a carriage. In everyday operation, the unit measures and records acceleration and vibration signals, it then processes this data and transmits all the information wirelessly to a back-office collection point, where reported information can trigger required actions. The device doesn’t only help operators understand the condition of wheels and track, but is also designed to identify vibrations caused by other problems on the train, such as faulty bearings. SKF, Samantha Joubert, Tel: (011) 821-3602 Email: samantha.joubert@skf.com, www.skf.com

PALIFENCE Salient Features

• Difficult to Climb: The spaces between the Horizontal wires are too narrow for fingers to have grip • Impregnable: Extremely difficult to cut with a hand cutter as the beak of a wire cutter will not be able to penetrate the horizontal wires • Excellent Replacement option to Solid Wall as: What is High Security 1. More economical than a solid wall Weld Mesh 2. Faster to install than a solid wall HIGH Security Weld Mesh 3. CCTV Camera has a clear view is wire fused and welded • Further upgrade possible with electric security system at a Horizontal distance • Anti-corrosive & low maintenance

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Manufactured according to BS EN 10016-2 Wire Sizes in accordance with BS EN 10218-2 Tolerance on Mesh Size in accordance wiht EN 10223-7 Tolerance on Panel Size in accordance with EN 10223-4 Welding Strength in accordance with BS EN 1461 Zinc Coating in accordance with EN 10245-1 Anti Corrosion in accordance with BS En 3900 E4/F4

Tensile Strength

• Wire has a tensile strenght of min 550 MPA

MARK: 083 454 6488 Email: mark@palifence.co.za

of 76.2mm and a vertical distance of 12.7mm also known as 35B/3510 where 3 denotes 3”(distance between vertical wires), 5 denotes 0.5” (distance between horizontal wires), and B or 10 denotes gauge of wire

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TRANSFORMING FREIGHT LOGISTICS

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TRANSNET FREIGHT RAIL

www.transnet.net www.transnetfreightrail-tfr.net

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WORLD-CLASS performance requires speed, agility and endurance

STRATEGY

INFRASTRUCTURE

OPERATIONS

Planning strategic direction benchmarked to world-class standards

Development of world-class infrastructure from concept to realisation

Development of operations to best practice and world-class standards

Supply Chain Strategy

Facility Design & Development

Process & Operations Design

• Supply Chain network analysis & design • National & Regional DC strategy development • Facility Sizing and OPEX estimates • On-line fullllment • Slow vs. Fast movers network set-up • A Supply Chain that supports business strategy • Site development strategies • Technology, IOT and digitilisation strategy

• Greennelds site development

• Operations assessment and benchmarking • WMS / WCS review • WMS / WCS functional requirements • Process and operations optimisation • Long term operational development strategies • Process audit • Labour standards and incentive programs

planning • Brownnelds site development planning • Functional building requirements speciication • Technical liaison to professional / development team • Facility sizing requirements (short to long term) • Design to execution • Procurement, program and vendor management

In today’s competitive business world you need to focus on every opportunity to advance your company mission

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Cape Town: (021) 816 2000 | ils-ct@ils.co.za Johannesburg: (011) 656 1100 | ils-jhb@ils.co.za VOL 69 July 2019 www.ils.co.za

SAFETY

Diesel Pumps Ready to Tackle Fires With municipal services under strain in most South African cities, companies must now provide their own water and pumping facilities in case of fire, but keeping the diesel powered ‘fire pumps’ in working order needs regular and expert maintenance.

“

New buildings increasingly require their own water storage tanks to draw from in the event of a fire,” says Reef Fuel Injection Services director, Andrew Yorke. “They also need their own booster pumps to generate the required pressure to fight a fire at height.”

As an organic fluid, diesel does not stay fresh forever and this can, in particular, affect the ability of the fuel injection system Andrew highlights that the standalone diesel engines driving these pumps generally do not run regularly. Apart from not being good for most engines, this also raises the risk that they may not start or perform optimally when a fire incident occurs.

Regular service intervals

“As an organic fluid, diesel does not stay fresh forever and this can, in particular, affect the ability of the fuel injection system,” he says. “It is therefore imperative to service the injection system regularly, so that the fire-fighting capacity in any building is

not compromised.” The servicing that is required tends to focus on checking and flushing the fuel pump and injectors, testing the calibration, and repairing any of the components if necessary. He notes that, apart from the danger of the engine not starting when a fire is detected, there is also a danger of damaging an engine by running it when the fuel injection system is faulty. “This can even lead to catastrophic engine failure,” he says. “At best, this will cost a company dearly if it is just conducting a test run on the engine after years of dormancy. At worst, the engine could fail during a fire, with the consequent loss of property and even life.”

No warm-up time

Unlike a vehicle, water pumps and generator sets are designed to accelerate to operating speed immediately on start-up. Any faults in the system therefore manifest quickly and could cause extensive damage. “So, it’s important to test the fuel injection system even before the pump is regularly tested,” Andrew concludes. Reef Fuel Injection Services Andrew Yorke Tel: (011) 873-2354 www.reeffuel.co.za

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TRACE In is a glo antio leading party ri

TRACE due diligence solutions are based on internationally accepted best practices and our experience and familiarity with the compliance needs of multinational companies. Services range from a denied parties screening to enhanced due diligence, including TRACE Certified Due Diligence.

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nternational, Inc. obally recognized bribery business organization and provider of third isk management solutions.

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VOL 69 July 2019

ENVIRONMENT

Tackling Water Loss the Clever Way A new product tackles inefficient water loss and preserves the environment.

irector of Aqua Plastech, Andre Fourie, recognised the immense water loss experienced in leaking dams. After research, trying multiple products and spending a fortune on repairs, he quickly realised how much water loss and environmental damage a leaking dam or pond can cause.

After losing a fair amount of water and attempting to repair a leak with various products, I found the whole process to be costly, inefficient, time consuming and harmful to the eco-system

“It was through my own experience that I realised there has to be a better way to seal leaks and cracks. After losing a fair amount of water and attempting to repair a leak with various products, I found the whole process to be costly, inefficient, time consuming and harmful to the eco-system.” he says. Water loss in earth dams and ponds is mainly caused by cracks and leaks that traditionally require expensive repairs and full drainage. Aqua Plastech was developed to bring cost effective, time-saving, eco-friendly and water preserving alternatives to dam and pond maintenance.

Bio friendly

Aqua Plastech Dam & Pond Sealer is a high-tech polymer that is a bio friendly solution which encourages water use efficiency by simply applying it to the surface of the water. The solution reacts instantly once in the water, expanding and sinking into cracks and leaks, requiring little waiting time with no extra loss of water. UberSeal is a water based general purpose clear waterproofing compound designed for use on a wide variety of substrates. It is especially suited to sealing and protecting porous vertical masonry surfaces like split faced or decorative concrete blocks. It is particularly effective against winddriven rain and unlike ‘water repellent’ style sealers, it is able to withstand hydrostatic pressures caused by significant weather events. Aqua Plastech Andre Fourie Tel: 086-199-5036 Email: info@aquaplastech.co.za www.aquaplastech.co.za

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dŚĞ ƐƐŽĐŝĂƟŽŶ ŽĨ ^ŽƵƚŚ ĨƌŝĐĂŶ YƵĂŶƟƚǇ ^ƵƌǀĞǇŽƌƐ

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VOL 69 Thornhill July 2019Oﬃce Park • Bekker Road • Vorna Valley • Midrand

ENVIRONMENT

Dealing With Waste A solution from FLSmidth which combines filtered mine tailings with waste to form GeoWaste also lowers water usage, rehabilitation costs and tailings footprints.

ccording to FLSmidth Regional Product Line Manager, Leonard Neluvhola, the Ecotails solution is nearing the end of a lengthy testing process by one of the world’s leading gold producers. “The success of its application to date confirms that Ecotails will be a game-changer for the mining sector,” says Leonard. “Not only can mines improve their environmental performance by applying this system, they will see bottom line benefits too.”

Not only can mines improve their environmental performance by applying this system, they will see bottom line benefits too The Ecotails solution involves dewatering and filtering tailings to a point where moisture content is just 10% to 25%.

Environmental impact

be reused in the plant,” he says. “This is a vast improvement on pumping highly diluted slurry to a conventional tailings dam, where the water is lost to evaporation.” The drier tailings are then mixed with the mine’s waste rock after it has been sized and screened to be transportable by conveyor. The resulting GeoWaste can be placed by a stacking system, as it is much more stable than wet tailings and can be stacked higher on a smaller footprint. This helps to address the concern mines have about the large footprints consumed by their tailings dams and waste rock dumps. In addition to its greater stability, GeoWaste is more conducive to vegetation growth. It is an ideal medium for concurrent environmental rehabilitation. The concurrent approach is becoming more popular, as it can mitigate the costs and risks of mine closure. Wet tailings can also present a greater danger of land contamination through leaching. FLSmidth Leonard Neluvhola www.flsmidth.com

“Up to 90% of the water in tailings can therefore

The FLSmidth EcoTails tailings solution is a game changing opportunity for the mining sector

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HEALTH AND SAFETY

Combining Sprinklers With Smoke Control a Must

ASP Fire CEO, Michael van Niekerk

Automatic sprinklers and smoke-control ventilation systems are not incongruous. However, they must be designed explicitly with each other in mind when approaching a firesafety system design for a building.

he primary, and most important, fire-safety objective is that the protection of occupants or users, including persons with disabilities, is ensured, and that provisions are made for the safe evacuation of such occupants or users. â&#x20AC;&#x153;Life safety is paramount. One is able to rebuild a building, or replace goods or equipment destroyed in a fire, one cannot replace a life lost to fire,â&#x20AC;? ASP Fire CEO, Michael van Niekerk stresses.

Hot smoke and toxic gases, are responsible for more deaths in fires than direct exposure to flames SANS 10400-T prescribes the maximum areas and storage heights for various occupancies that are permitted without the installation of an automatic sprinkler system. Sprinklers are necessary when a fire load within a building is so great that it renders human intervention within an enclosure impossible.

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Sprinklers are also necessary for life safety when the floor area, horizontal travel distances, or height of a building requires protection of the occupants during an evacuation. One can, however, compartmentalise a large building, or provide emergency routes, so that occupants can move from the origin of a fire to a separate, safer area within the building and, ultimately, to the street or safe area outside of the building.

Sprinklers not always needed

Sprinklers are therefore not mandatory in all buildings where adequate life safety systems are installed. Smoke ventilation is required in any enclosure greater than 500m2 in floor area. SANS 10400-T states in Section 4.42 that an enclosure with a floor area greater than 500m2 shall be provided with a smoke-control system designed in accordance with EN 12101. Furthermore, any single-storey building with a floor area of up to 2 500m2 not fitted with a sprinkler protection system shall be provided with either a mechanical or natural smoke control system as set out in that section.

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The purpose of a Control-Mode Density Area (CMDA) sprinkler system is to control or contain a fire or, in the case of an Early Suppression Fast Response (ESFR) system, extinguish a fire, instead of preventing smoke from being generated. Hot smoke and toxic gases, however, are responsible for more deaths in fires than direct exposure to flames. “There are numerous case studies that support this,” Michael points out. Steel and concrete structures are vulnerable to high temperatures that will build up without adequate smoke ventilation during a fire. Unprotected steel loses 50% of its stiffness and strength at between 450°C to 550°C, termed the critical temperature of steel, resulting in sagging of beams or trusses that apply horizontal loads to weakened vertical steel structural members designed primarily for vertical loads. “The end result is total building collapse,” Michael warns. Concrete is similarly affected by temperatures around 700°C, resulting in spalling and the exposure of the internal steel reinforcing to high temperatures. Sprinklers will also assist in cooling hot gases produced by a fire, aiding in preventing structural damage to a building. However, they do not scrub toxic gases such as hydrogen cyanide or hydrogen sulphide from the smoke.

Working hand-in-hand

“A literature review of the South African, British, and North American fire standards reveals that sprinklers and smoke ventilation systems are, in fact, complimentary when installed together,” he says. “There is even a suggestion that sprinklers have a symbiotic relationship with smoke venti-

Sprinklers are not mandatory in all buildings where adequate life safety systems are installed lation systems, resulting in a greater number of sprinklers activating when installed with smokecontrol ventilation. “Sprinklers and smoke-control ventilation systems each have their place in the fire-safety design of a building. They can be installed together or independently, depending on the fire-safety objectives and requirements of the building in question,” Michael concludes. ASP Fire Michael van Niekerk Phone: (011) 452-2169 Email: michael@aspfire.co.za www.aspfire.co.za

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MECHANICAL PATHOLOGY

The Engine Killers I have a colleague who believes that engines don’t just simply die, they are murdered. A rather dramatic sentiment, I know, but then we take the death of an engine quite seriously at WearCheck.

eing an avid consumer of forensics crime drama television series like CSI (Crime Scene Investigation) I feel that I can confidently explain the procedure that takes place once a murder victim has come to the attention of the authorities. Firstly, the crime scene is cordoned off. A forensic team examines the evidence, the cause of death is determined and a murder case is opened based on the strength of the evidence collected (which is usually bizarre in nature and requires the expertise of a socially awkward forensic pathologist).

Steven Lara-Lee Lumley

Similarly, when reviewing oil analysis data, a forensic approach is also required that incorporates a combination of science, experience and gut instinct. There is an explanation for every oil analysis result obtained but that explanation is not always apparent and requires the abilities of a very special kind of pathologist, a mechanical pathologist also known as a WearCheck diagnostician.

Lethal engine oil contaminants

In this article, we will take you on a journey through the eyes of a mechanical pathologist tasked with identifying the modus operandi of some of the most lethal engine oil contaminants known to cause premature or even sudden engine failure. One of the main functions of oil analysis is to monitor levels of contaminants in the lubricating oil. Contaminants can be classed as being either internal or external. Internal contaminants are generated within the mechanical system such as wear debris or combustion by-products that accumulate in an engine oil as a result of burning diesel. External contaminants are substances that exist in the environment that should not be in the oil like airborne dust or water contamination. Contaminants can be directly damaging to the mechanical system being lubricated, for example dust is abrasive and can cause components to wear abnormally but contaminants can also be indirectly damaging as they can cause the lubricating oil to degrade which in turn may have an adverse effect on a mechanical system being lubricated.

One of the main functions of oil analysis is to monitor levels of contaminants in the lubricating oil After lengthy interrogations with several suspected engine oil contaminants, we have compiled forensic profiles on what we believe to be the most brutal killers known to the diesel engine.

Disturbing and graphic content

Let us begin our journey into the mechanically macabre with our first engine killer or fuel dilution AKA ‘The volatile killer’. This engine killer was responsible for 21% of all engine related problems detected by WearCheck in the last year. When unburned fuel leaks directly into the sump the problems caused are twofold, there is a physical and a chemical effect. Let’s examine these modes of attack in more detail.

Physical affect

The kinematic viscosity of a fluid is defined as a fluid’s resistance to flow under the force of gravity at a particular temperature. Viscosity is considered one of the most important physical properties of a lubricating oil as it determines the thickness of the oil film that prevents contact between metal surfaces. For a mental comparison think of water as having a low viscosity (flows easily) and honey as having a high viscosity (does not flow as easily). The typical kinematic viscosity of

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diesel is between 2 to 5 cSt @ 40°C (think water) and the typical viscosity of a common diesel engine oil, say a SAE 15w/40 is about 100 cSt at 40°C (think honey) so as a result of this difference in viscosities between diesel and engine oil only a small amount of fuel is required to significantly reduce the viscosity of the engine oil. Moderate (+/-4%) to large (+/-8%) amounts of fuel dilution can drop the viscosity of an engine oil by several grades which can collapse critical oil film thickness. This reduction in viscosity will eventually lead to a reduction in the load bearing capabilities of the oil and abnormal bearing wear will eventually occur.

Chemical affect

Diesel engine oils are blended with additives that have specific functions to perform, for example anti-wear, anti-oxidant, dispersant and detergent type additives to name a few. When large amounts of fuel are present in engine oil these additives become physically diluted which reduces their effectiveness. Diesel also contains unsaturated aromatic molecules which facilitate oxidation of the engine oil resulting in a loss of the much-needed detergent additive responsible for neutralising acids generated in the engine oil as a result of the combustion process, extended oil use or high operating temperatures. The loss of this detergency in the oil results in increased corrosion of internal metal surfaces.

AKA the ‘the dirty killer’. This engine killer was responsible for 15% of all engine related problems detected by WearCheck in the last year. The dire consequences of dust entry are perfectly summed up by Jim Fitch of Noria Corporation who maintains that the cost of excluding one gram of dirt is only about 10% of what it will cost you once you let it enter the oil.

Diesel engine oils are blended with additives that have specific functions to perform, for example anti-wear, anti-oxidant, dispersant and detergent type additives Due to the large volumes of air that engines take in through the induction system, they are at high risk of dust entry and the resultant accelerated wear that takes place due to abrasion. Interestingly enough, it is the particle that has its smallest dimension of a similar size to the clearance involved that does the most damage. A particle smaller than the clearance will pass straight through doing little harm and a particle larger than the clearance will be unable to enter and do any damage.

To make matters worse, diesel is also made of heavier hydrocarbons that can turn to wax when ambient temperatures drop. If a fuel tank contains summer grade diesel and temperatures drop significantly, wax crystals can form causing a blockage in the fuel filter. Similarly, diesel fuel dilution in cold operating temperatures can cause waxing of the engine oil which could result in low oil pressures and oil starvation in severe cases. Final note in forensic profile: This killer has been known to cause wash-down of oil on cylinder liners, accelerated top-end wear as well as high blow-by condition and increased oil consumption.

The dirty killer

The second killer in our forensic profile is dust entry

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Dust does the most damage at the point of entry so when an engine has a dust entry problem the type of wear that takes place is often related to the manner in which the dust enters. For example, an oil sample showing evidence of dust entry and an increase in bottom-end wear indicates that dust is entering the engine oil directly and not passing the pistons and rings. Any dust which is in the oil will usually be pumped through the oil filter before entering the bearings.

The dark killer

The third killer in our forensic profile is soot AKA the ‘the dark killer’. This engine killer was responsible for 6% of all engine related problems detected by WearCheck in the last year.

Contaminants can be directly damaging to the mechanical system being lubricated, for example dust is abrasive and can cause components to wear abnormally but contaminants can also be indirectly damaging Let’s face it, burning fossil fuel is a dirty business and due to the inherent impurities and inefficient engine combustion cycles it is not possible to burn fossil fuel with 100% efficiency. One of the major combustion by-products of burning diesel is soot. Soot is impure carbon particles resulting from the incomplete combustion of diesel. When formed in an engine the soot particles are small (+/-0.03 microns) but with progressive fuel usage large quantities of these particles are deposited in the oil and eventually agglomerate to form larger soot particles. All engine oils contain detergent and dispersant type additives which control the effects of soot. The detergent additive keeps metal surfaces free of deposits while neutralising compounds that can form sludge and varnish. The dispersant additive works by keeping insoluble contaminants (like soot)

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dispersed in the lubricant and prevents them from coating metal surfaces. However, these additives, like all oil additives, are sacrificial in nature and once used up they will not be able to protect the oil from degradation and continued soot accumulation or agglomeration. The most dramatic effect of excessive soot is the viscosity increase which results in higher operating temperatures and accelerated wear. The oil might still be able to flow and provide sufficient lubrication at operating temperatures of 90°C but when it cools down to 10°C during the night, the oil can solidify. Under these adverse conditions, when the engine is started the oil pump will not be able to pump this solid mass leading to oil starvation. But wait, it gets worse, EGR (Exhaust Gas Recirculation) units on diesel engines amplify the amount and abrasivity of soot production as the device channels the emissions back to the combustion chamber creating a multi-pass opportunity for soot to deposit in the oil.

The cool killer

Finally, the pièce de résistance of engine killer ‘The internal coolant leak’ AKA “the cool killer”. This engine killer was responsible for 13% of all engine related problems detected by WearCheck in the last year. This is the most brutal engine killer of them all and a testament to this is the fact that the majority of diesel engine manufacturers estimate that 53% of all catastrophic engine failures are due to cooling system problems. So, what is the modus operandi of this coolest of engine killers you might ask? Well, the answer lies in a Hannibal Lecter quote “Of each particular thing, ask what is it in itself? What is its nature?”. Generally, most coolants are a mixture of water, glycol and additives. The water acts as the heat transfer

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the oil’s viscosity and this can lead to insufficient flow of the oil to critical metal surfaces. Added to this glycol and its reaction by-products can also aggressively promote oxidation of the base oil which will further thicken the oil. Remember, If it’s too thick…it can’t flow…if it can’t flow…it can’t cool so any dramatic increase in the oil’s viscosity will have an adverse effect on the oil’s cooling ability.

Oil filter plugging

The acids and water that form in engine oil as a result of coolant contamination can disrupt soot dispersancy. A prominent oil filter manufacturer claims that 75% of filter plugging complaints in engine oil filters involve coolant in the crankcase and that just 0.4% coolant in engine oil is enough to coagulate soot and cause dump out leading to sludge, deposits, oil flow restriction and filler blockage.

Internal coolant leaks can sometimes be confusing as there is often no physical water present in the oil Abnormal wear medium while the glycol component of the coolant raises the boiling point and lowers the freezing point of the water it is mixed with. The additive portion of the coolant is there to protect metals in the cooling system from corrosion, cavitation, scale formation etc. Internal coolant leaks can sometimes be confusing as there is often no physical water present in the oil. This is due to the operating temperatures and pressures in the engine which ensure that the water evaporates off. However, the additives in the coolant will contribute to elemental concentrations of sodium, boron, potassium and silicon in the oil and it is this elemental family from the coolant additive system that serves as a marker to confirm coolant contamination of the oil. Coolant can leak into engine oil in a variety of ways, for example from a defective seal, blown head gasket, damaged or corroded cooler core, water pump seal failure but one of the most common causes of an internal coolant leak is liner perforation. Liner perforation occurs when the liners vibrate to the rhythm of the piston movement during the compression and combustion stroke. This movement causes pressure waves to form negative pressure regions that nucleate vapor bubbles. As the combustion chamber fires, these vapour bubbles implode and can literally blasts small holes in the liner wall. The introduction of coolant into lubricating oil can expose your machine to a dangerous mixture of chemicals that can progress to engine failure in a short period of time. Here we list just some of the known modes of attack this engine killer has displayed in past murder cases.

Viscosity change

Glycol contamination of engine oil can increase

Glycol oxidises into corrosive acids which can cause a rapid drop in the oil’s alkalinity (total base number) resulting in an unprotected corrosive environment which can increase corrosive wear of engine bearings and other internal metal surfaces.

Additive precipitation

Glycol can react with oil additives causing precipitation. ZDDP (zinc dialkyldithiophosphate) is an important anti-wear and anti-oxidant additive found in almost all diesel engine oils. When the engine oil is contaminated with glycol, ZDDP will form reaction products and this leads to a loss of anti-wear and anti-oxidant performance.

Oil balls

Oil balls are abrasive spherical contaminants that form from the reaction of the detergent additives in the oil and glycol contamination. Oil balls are a known cause of damage to crankcase bearings and other frictional metal surfaces in the engine.

Forensic profile close-out

The time taken for engine failure progression can vary significantly for the contaminants profiled in this article. There are also several aggravating factors that can drastically shorten the failure development period like deficient maintenance practices, oil quality and filtration. Sudden-death engine failures from moderate concentrations of contaminants are usually accompanied by one or more of these aggravating factors whereas high concentration of contaminants in an engine oil can result in sudden-death failure irrespective of any aggravating circumstances. What is most commonly seen however is when the moderate scenario is unattended to by the engine operator and escalates over time until engine failure eventually occurs. WearCheck Stephen Lara-Lee Lumley Tel: (011) 392-6322 Email: support@wearcheck.co.za www.wearcheck.co.za

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Your boutique business destination Surrounded by lush gardens in the hub of Johannesburgâ&#x20AC;&#x2122;s northern suburbs, The Peartree in Craighall Park caters for groups of fifteen through to 100 guests in three well-appointed and equipped business suites. Breakfast meetings, working lunches, indoor or outdoor dining, half-day and full-day packages including all welcome refreshments, teas and lunches are offered in Standard, Gold and Platinum packages. Secure parking, Wi-fi, lockable space, all underpinned by highly qualified and helpful staff dedicated to ensuring your event is a success, make The Peartree a destination of choice.

www.thepeartree.co.za e-mail: info@thepeartree.co.za Tel: 011 781 1401 41 St. Albans Ave, Craighall Park

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VALVES

Controlling The Flow BMG’s range of industrial slurry valves, which has been designed to cope in harsh conditions, includes robust butterfly and knife gate valves, as well as diaphragm and pinch valves.

“

These industrial slurry valves are highly efficient for the control and isolation of abrasive slurries in many industries, including power generation, chemical and petrochemical, cement handling, water treatment, mining, quarrying, pulp and paper,” says Willie Lamprecht, national product manager for valves, BMG.

“Failure of a valve and subsequent leaking of corrosive media can have devastating effects on the safety of personnel and equipment, leading to premature system failure and costly downtime.

Also in the range, are unlined diaphragm valves, which are suitable for water treatment and general industrial applications

Various valves available

Polyurethane-lined knife gate valves are available from BMG in standard sizes between DN 50 and DN 600, with manual, pneumatic and electric actuation. These knife gate valves have a wafer pattern and are manufactured from cast and ductile iron, with stainless steel discs. They can withstand operating temperatures of between -20˚C and +80˚C as standard, with higher temperatures on request. Polyurethane liner abrasion-resistant butterfly valves in a wafer pattern or with a lugged design are used for on-off and control of abrasive slurries. Butterfly valves are available in standard sizes between DN 50 and DN 400. Locally-manufactured Klep BMG diaphragm valves between DN 50 and DN 350, with manual or pneumatic actuation are designed for abrasive slurry applications. These flanged diaphragm valves have a body pressure of PN 10 and can withstand temperatures between -10°C and +80°C.

Don’t forget the rubber

Long-lasting rubber and jumbo rubber linings are suited for full-bore diaphragm valves with a high flow capacity and an efficient sealing capability, which shuts off any flow and prevents leakage. Full bore diaphragm valves also have a low pressure drop because there is almost nothing obstructing the flow of the fluid when the valve is fully opened. This creates little resistance to flow, which makes these valves suitable for fluids with abrasive particles. Also in the range, are unlined diaphragm valves, which are suitable for water treatment and general industrial applications. FPV pinch valves featuring a design where the sleeve is pinched to close mechanically or automatically by means of hand-wheel or actuator are ideal for the control and isolation of abrasive slurries. Open frame pinch valves are available with a short and long frame design, in sizes between DN 50 and DN 600. The body is made from mild steel, but stainless steel is also available for specific applications. These valves, with soft rubber sleeves, have manual, hydraulic and pneumatic actuation and can withstand temperatures between -20°C and +80°C. BMG Willie Lamprecht Tel: (011) 620-1581 Email: williaml@bmgworld.net www.bmgworld.net

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High security welded mesh

Pallisade

Gates

Gate Automation

Razor wire and more ....

What is High Security Weld Mesh HIGH Security Weld Mesh is wire fused and welded at a Horizontal distance of 76.2mm and a vertical distance of 12.7mm also known as 35B/3510 where 3 denotes 3”(distance between vertical wires), 5 denotes 0.5” (distance between horizontal wires), and B or 10 denotes gauge of wire

Salient Features • Difficult to Climb: The spaces between the Horizontal wires are too narrow for fingers to have grip • Impregnable: Extremely difficult to cut with a hand cutter as the beak of a wire cutter will not be able to penetrate the horizontal wires • Excellent Replacement option to Solid Wall as: 1. More economical than a solid wall 2. Faster to install than a solid wall 3. CCTV Camera has a clear view • Further upgrade possible with electric security system • Anti-corrosive & low maintenance

Standards

• Manufactured according to BS EN 10016-2 • Wire Sizes in accordance with BS EN 10218-2 • Tolerance on Mesh Size in accordance wiht EN 10223-7 • Tolerance on Panel Size in accordance with EN 10223-4 • Welding Strength in accordance with BS EN 1461 • Zinc Coating in accordance with EN 10245-1 • Anti Corrosion in accordance with BS En 3900 E4/F4

Tensile Strength • Wire has a tensile strenght of min 550 MPA

MARK: 083 454 6488 34

Email: mark@palifence.co.za

www.palifence.co.za

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MARKET FORUM

Lowering the TCO through water maintenance Increasing pressure to lower the total cost of ownership (TCO) has seen many mining operations review their water management strategies. Integrated Pump Rental reports that this has led to increased enquiries about its locally manufactured solutions that mitigate the challenges of silted process water ponds. Ruaan Venter, development manager at Integrated Pump Rental, says there is now a more proactive stance being taken on the monitoring of these water reservoirs. Adding to the challenge of water short-

ages is the need for mining operations to reduce their reliance on municipal water supplies. This means that efficient monitoring of process water ponds is critical in terms of the recycling and reuse of water for the plant and other purposes on a mine. Ongoing monitoring of process water ponds will facilitate desilting activities on a rotational basis. This will eliminate the disruption of unexpectedly having a pond out of service. “Taking this concept one step further, we have found that mines are investing

in their own SlurrySucker equipment,” Ruaan says. The SlurrySucker was developed by Integrated Pump Rental for applications where the water retention and water holding capacity of process ponds is threatened. It is also ideal for the dredging and cleaning of water capture areas where silt or slime has become an issue. Integrated Pump Rental Tel: (011) 894-2906 Email: admin@pumprental.co.za www.pumprental.co.za

The SlurrySucker is was developed for applications where the water retention and water holding capacity of process ponds in threatened

26 Nagington Road, Wadeville, Germiston 1400, South Africa Tel +27 11 824 4810 / Fax +27 11 824 2770 E-mail info@apepumps.co.za / info@matherandplatt.com Website www.apepumps.co.za / www.matherandplatt.com

Split Case Pump • Sugar and Paper Mills • Refineries • Petro Chemical

Vertical Turbine • Cooling Water • Circulation • Irrigation

Horizontal Multistage Pump • Power Generation Plants • Cooling and Heating Systems • Mining Applications

Locally Manufactured

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MARKET FORUM

Greasing food without the contaminants Oven chains need to operate freely and smoothly in food manufacturing facilities, but lubricating these chains is tricky, given the intense temperatures they are subjected to. Without good lubrication, chains harden due to heat and moisture, which causes corrosion and oxidation. This can eventually lead to the premature failure of oven chain pins and brushings, as well as introducing contaminants into food and thereby compromising food safety. Only the most robust lubricant formulations can perform in this application, and these must also be food-grade lubricants, which means they need to be approved for incidental food contact (category H1 of food-safe lubricants). Roan Van Der Walt, Sales Technician at Lubrication Engineers (LE) SA, explains that the problem is that most lubricants melt under the extreme heat ovens are subjected to, and then they don’t stick to the hot oven chains. He says it’s therefore necessary to use a specialised lubricant. “There are two main ways to lubricate oven chains. You can use a liquid lubricant, or a solid lubricant that is suspended in a carrier fluid. Both of these options are designed to stop metal

surfaces from coming into direct contact with one another, which cuts down on friction and wear and tear,” Roan says. “The LE Ovenworx H1 Syn Chain Lubricant (4061) has been formulated specifically to combat the demanding conditions oven chain applications require,” Roan concludes. Lubrication Engineers SA, Callum Ford, Tel: 011 464-1735 Email: callum@lubricationengineers.co.za www.lubricationengineers.co.za

RELIABLE ENERGY SOLUTIONS for the entire mining sector.

Renewable Energy: Wind & Solar Electrical Construction Standby/Emergency Generator Sets

LV Motors, Drives, Softstarters & Switchgear

Electrical Infrastructure Solutions

Motor Scan Power & Distribution Transformers

Invicta Vibrator Motors

Power Generation Solutions

Overhead Lines

MV Drives, Softstarters and Switchgear

Automation Control Room

Mobile Substations MV Slipring Motors Motor Control Centres, Panels & Distribution Boards Mini Substations

Zest WEG Group is able to offer a range of standard off-the-shelf products as well as end-to-end energy solutions by leveraging best practice engineering and manufacturing capabilities.

E-Houses and Containerised Substations

All products are engineered to facilitate a safe and reliable mine and plant with operational stability and the highest possible production levels as an objective. Reduced maintenance and ease of serviceability assist in lowering the total cost of ownership for the mine.

1 36ZWG_mining_130mmx180mm.indd THE SOUTH AFRICAN MECHANICAL ENGINEER

Tel: 0861 009378

VOL 69 July 2019

www.zestweg.com

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MARKET FORUM

Multi-mount cast iron electric motors now in SA Bearings International (BI) has introduced a multi-mount cast iron Bauer electric motor range onto the market that can accommodate the terminal box on the top, left-hand or right-hand side. The major benefit for customers is that it reduces duplicate stockholding to accommodate different terminal box positions. Traditionally, cast iron electric motors were available in a wide range from 0.37kW up to 400kW, with BI only catering for top-mounted terminal boxes. “Some plants either have top, left-hand or right-hand terminal boxes, making it a complex and costly exercise to stock all three,” BI Bauer electric motors product manager, Lewis Hiepner, explains. The Bauer motor range from BI is also available in various energy efficiency ratings, from IE1 as standard and IE2 high efficiency, all the way through to IE3 and even IE4. Bearings International Lewis Hiepner Tel: (011) 899-0000 Email: info@bearings.co.za www.bearings.co.za

Cloud usage set to double American based Nutanix has announced the findings of its Enterprise Cloud Index results for the manufacturing sector, measuring manufacturing companies’ plans for adopting private, public and hybrid clouds.

current productivity and operational goals in an increasingly global and highly competitive marketplace, but they also need to invest in future growth.

The report revealed that the manufacturing industry’s hybrid cloud usage and plans outpace the global average across industries. The deployment of hybrid clouds in manufacturing and production companies has currently reached 19% penetration, slightly ahead of the global average. Moreover, manufacturers plan to more than double their hybrid cloud deployments to 45% penetration in two years, outpacing the global average by 4 percent.

Nutanix Email: pr@nutanix.com www.nutanix.com

The manufacturing industry is at an ‘innovation impasse,’ meaning manufacturers have a desire to innovate and drive transformation, but legacy IT systems have the potential to constrain their ability to do so. The opportunity for manufacturers to embrace digitisation efforts including Industry 4.0 initiatives can break the impasse, but executives must focus on new opportunities to create value and not only prioritise traditional business operations. Manufacturing organisations face the constant challenge of trade-offs, they are under pressure to meet

THE SOUTH AFRICAN MECHANICAL ENGINEER

VOL 69

July 2019

One pump to handle any slurry

On the Move

Boasting a one-piece frame for correct alignment of bearings, seal and impeller to front liner, the Warman WBH is engineered for enhanced efficiency and operational savings. The pump incorporates a fully adjustable and rotatable throatbush to evenly spread the wear and maintain the pump’s performance for longer periods. The ‘One Point’ front liner adjustment feature allows the pump to rotate and axially move to minimise the front impeller gap to reduce wear and maintain performance. Significantly, this adjustment can be made while the pump is running.

Rudi Rudolph

The streamlined impeller inlet of the Warman WBH pump facilitates enhanced handling of even the most difficult slurries, while the low-flow gland seal, expeller seal and mechanical seal options on the pump mean there is less dilution of the slurry and lower required flow of gland water.

Kathy Shepherd

Bearings International (BI) has appointed Rudi Rudolph as Segment Leader for manufacturing and Kathy Shepherd as Business Development Leader (BDL) for Wholesale and Retail.

Weir Minerals Africa Tel: (011) 617-0700 Email: sales-za@weirminerals.com www.minerals.weir

Drone cuts back on inspection costs Skyriders Access Specialists set a new record when it deployed its Elios SkyEye confined-space drone for the first time in the massive internal space of the back-pass ducting at a major coal fired power station in Limpopo. The back-pass ducting conveys the hot exhaust gases and fly ash to the precip hoppers, and ultimately to the smokestack. This space measures 6m by 6m, and is about 35m high, which means that installing the necessary scaffolding in order to gain access for any inspection purposes is extremely costly compared with end result, which may even be that no repair is necessary. “We can use our Elios SkyEye drone to inspect the entire area rapidly and thoroughly,” Skyriders Marketing Manager, Mike Zinn, says. If any repair work such as welding or further Non-Destructive Testing (NDT) is required, highly qualified and experienced rope access technicians can be deployed. Skyriders Mike Zinn Tel: (011) 312-1418 Email: mike@ropeaccess.co.za www.ropeaccess.co.za

THE SOUTH AFRICAN MECHANICAL ENGINEER

The Warman WBH pump is typically used in heavy duty applications such as mill discharge, slurry transfer and process pumping applications

VOL 69 July 2019

THE SOUTH AFRICAN MECHANICAL ENGINEER

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July 2019

Invincible Valves (Pty) Ltd was established in 1982 and since has grown to a medium sized enterprise located in Knights, Germiston Invincible Valves prides itself on service excellent and flexibility by striving to enhance our customer’s bottom line. Our 6,500m² facility in Knights is made up of 4,500m² under roof being our stores and workshop. The facility is fully equipped to offer a one-stop resource for valves and ancillary equipment which we transport globally. As an approved BBBEE Level 4 supplier to all major industries within South Africa, we maintain expertise and experience across a broad spectrum of industries and applications with a wide range of products. We offer a comprehensive range of local and imported valves and accessories for the mining, petro-chemical, power generation, water, sewerage and general industries. We have agents in all major centres around the country and service all four corners of the globe. We offer an in-house rubber lining service for valves, pipes, fittings and vessels which is utilized by many of the country’s major valve manufacturers. In addition we offer complete service, repair and valve reconditioning services for all types of valves. Our Core Values: We believe in treating our customers with respect. We grow through creativity, invention and innovation. We integrate honesty, integrity and business ethics into all aspects of our business functioning. Our Mission Statement: Build long term relationships with our customers and clients, to provide exceptional customer services by pursuing business through innovation and advanced technology. Our Purpose: To be a leader in the Valve Industry by providing enhanced services, customer service and profitability. Our Vision: To provide a quality service that exceeds the expectations of our esteemed customers. Invincible Valves is a proud supplier of quality valve products and ancillary equipment backed by service excellence around the globe. It is the combination of these values that allows us to form lasting business relationships.

Invincible Valves (Pty) Ltd

If it's not INVAL®, it's not Invincible 33 Shaft Road, Knights, Germiston TEL: +27 (0) 11 822 1777 | FAX: +27 (0) 11 822 3666 EMAIL: enquiries@invalve.co.za | WEB: www.invalve.co.za