Bulk Handling Today March 2019

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BULK

HANDLING Endorsed by: CMA l LEEASA l SAIMechE l SAIMH

T O D A Y March 2019

CONVEYORS TO SECURE FUTURE FISH SUPPLY SWITCHING FROM TRACK TO ROAD WHILE TOWING 300 TONS


Conveying Excellence with High-End Conveyor Belts Every conveyor belt, every climate zone and every topography calls for perfect conveyor belt technology. ContiTech provides knowledge, experience, a globally encompassing and competent network and a broad product range to give your conveyor belt applications a technological lead. More than 140 years of rubber expertise make us a strong partner, enabling our customers to benefit from the synergies within the Continental corporation. We implement innovative conveyor belt technology reliably, sustainably and safely from development to commissioning and after-sales service.

conveying excellence

+27 (0) 11 248 9300 www.contitech.co.za


BULK

HANDLING Endorsed by: CMA l LEEASA l SAIMechE l SAIMH

T O D A Y March 2019

CONVEYORS TO SECURE FUTURE FISH SUPPLY

BULK

HANDLING March 2019

SWITCHING FROM TRACK TO ROAD WHILE TOWING 300 TONS

On the cover: Rema Tip Top South Africa Dunlop Industrial Products Tel: (011) 741-2500

T O D A Y

Contents 5 4

CMA News

Beltcon 19

29 Splice Failures Resulting from Rubber Compound Incompatibility

Company Profile

Cover Story 6

Cover Grade and Thickness Selection

Infrastructure 8

39

Market Forum

Endorsing Bodies

Addressing Ageing Pipelines

Pollution

CMA (Conveyor Manufacturers Association)

Conveying

LEEASA (Lifting Equipment Engineering Association of South Africa)

SAIMechE (SA Institution of Mechanical Engineering)

SAIMH (SA Institute of Materials Handling)

also mailed to members of the RFA (Road Freight Association)

10 Controlling Material Spills 12 Right Compound for the Belt

Mining

14 Maximizing Productivity With Surface Miners 19 Large Finds in DRC's Kasai River

Screens

21 Lower Cost of Ownership

Road-Rail

26 Emission-free Flexible Performance

Copyright

All rights reserved. No editorial matter published in “Bulk Handling Today” 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.

Our e-mail address is bulkhandling@promech.co.za Visit our website on www.bulkhandlingtoday.co.za

The monthly circulation is 3 673

Proprietor and Publisher: PROMECH PUBLISHING Tel: (011) 781-1401 E-mail: bulkhandling@promech.co.za www.promech.co.za Managing Editor: Susan Custers Advertising Sales: Louise Cresswell DTP: Sanette Badenhorst Administration: Netta Janse van Rensburg Subscriptions: Please email us at accounts@promech.co.za if you wish to subscribe to “Bulk Handling Today” at R550,00 (excl postage and VAT) per year; R1 380,00 per year for Africa/Overseas. Printed by: Typo Colour Printing, Tel: (011) 402-3468 FSC (Forestry Stewardship Accreditation)

BULK HANDLING TODAY

March 2019

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COMPANY PROFILE

Martin Engineering

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artin Engineering is a global leader in technologies to make bulk material handling cleaner, safer and more productive. Since 1944, Martin products have improved conveyor operations by minimizing dust and spillage at transfer points, removing carryback and controlling belt tracking. Martin Engineering specializes in belt cleaners, air cannons, engineered vibration, transfer point technologies, dust management and belt alignment. The company also provides specialized services such as equipment installation, process improvement, maintenance and silo cleaning. Martin Engineering's success can be attributed to the development of practical, field-proven, costeffective answers for “real life” problems. All products are designed for tough industrial conditions, built to allow easy maintenance and engineered for simplicity, cleanliness, safety and efficiency.

MARTIN® AIR CANNONS — safe, reliable & powerfully efficient —

KEEP MATERIAL MOVING & PROCESSES RUNNING The cutting-edge technology of the Martin® Hurricane Air Cannon features a positiveacting, centrally-located valve design representing state-of-the-art engineering, with the most direct air path, maximum force output, minimal air consumption, smallest footprint and simplest installation.

your comprehensive source for all flow aid solutions

+27(0)13 656 5135 | feedback@martin-eng.com | martin-eng.co.za air cannons • vibrators • silo cleaning services • training A GLOBAL FAMILY

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® Registered trademark of Martin Engineering Company in the US and other select locations. © 2015 Martin Engineering Company. Additional information can be obtained at www.martin-eng.com/trademarks.

BULK HANDLING TODAY

March 2019

They are proud to have a presence today in 19 countries across six continents, where their products and people deliver solutions to the problems associated with bulk material handling around the world. Quality products and services provided by their team of specialists help ensure that plants are cleaner, safer, more efficient and more profitable. The company's expanded South-African business unit has internal manufacturing operations that include welding and laser cutting operations, steel bending, urethane molding, painting and powder coating, assembly and packaging operations. Martin Engineering incorporates lean manufacturing principles to optimize the efficiency, safety and quality throughout. The company’s Center for Bulk Materials Handling Innovation (CFI) at the firm’s Neponset campus are at the leading edge of technology and invention. This building houses laboratories for Environmental, Metals, Polymers and Bulk Materials research, as well as test areas for conveyor products, air cannons and engineered vibration. A critical element of Martin Engineering’s success is its focus on training and knowledge-building across the many industries it serves. Since 1991 the company has been spearheading bulk handling training and education. Now in its fourth edition, the Foundations reference book and training series have trained plant operators, maintenance personnel and engineers about belt conveyors - how the equipment works and how to make it work better. The modules include basic training, operations and maintenance, as well as advanced education. The book has become a vital component of the international training programs developed by Martin Engineering, such as on-site workshops, online courses and certification.


CONVEYOR MANUFACTURERS ASSOCIATION

From The Chairman’s Desk

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t’s a Beltcon year this year and the International Materials Handling Conference is in full swing putting together a spectacular conference for Beltcon 20. That’s forty years of presenting industry with papers on the very latest conveyor technology. Speakers come from all over the globe as well as from local industry and Beltcon is organised FOR THE INDUSTRY, BY THE INDUSTRY, which keeps costs to an absolute minimum. The CMA is proud to be associated with Beltcon. Not only is the CMA an underwriter, but the entire Technical and Organising Committee is comprised of conveyor experts from among our members, so there is a very close relationship between the CMA and the IMHC. Please diarise the dates: 31 July and 1 August and if you would like to take advantage of early bird discounts, register now. Details can be found on the website www.beltcon.org.za. The first of the five Members’ Meetings for 2019 has already taken place, with the next one due on

Jay Pillay

16 April just before Easter. The Golf Day takes place on 12 April and the Annual Dinner is scheduled for 22 May. Various training courses are scheduled and details and registration forms for these can be found on the website www.cmasa.co.za for those interested in sending their staff for specialised training in all things conveyor-related. The website has recently undergone a complete revamp and is well worth a visit. Many people are not aware of the research projects that the CMA is spearheading, and there are also new items that have been earmarked for future projects that may be of interest to university students as well as those engineers looking for post-graduate research ideas. Jay Pillay Chairman Jay Pillay, Chairman

Membership at March 2019 All members subscribe to the CMA Code of Ethics Acrow Limited Actom Afripp Projects Altra Industrial Motion South Africa (Pty) Ltd Bauer Bearings International Belt Brokers Belting Supply Services BMG Bonfiglioli Power Transmissions Bosworth Brelko Conveyor Products CedoTech cc Closeal Manufacturing Collisen Engineering ContiTech South Africa (Pty) Ltd Conveyor Watch (Pty) Ltd Conveyor & Engineering Equipment CT Systems David Brown Gear Industries DRA Projects SA (Pty) Ltd Dunlop Belting Products

Dymot Engineering Company ELB Engineering Services Fenner Conveyor Belting (South Africa) Flexco SA (Pty) Ltd FLSmidth Roymec Giza Technologies (Pty) Ltd Habasit South Africa (Pty) Ltd Hägglunds Drives South Africa Hatch Africa (Pty) Ltd HMA South Africa (Pty) Ltd Hosch - Fördertechnik (SA) International Belting & Marketing (Pty) Ltd KevConBelt (Pty) Ltd Lesa Mining Equipment and Conveyor Belt Lorbrand Martin Engineering Megaroller Melco Conveyor Equipment Merlin consulting (Pty) Ltd Moret Mining Nautilus Projects (Pty) Ltd

Nepean Conveyors OE Bearings Oriental Rubber Industries SA Osborn Engineered Products Pegasus Industrial Services cc Regal Beloit South Africa Rema Tip Top South Africa Ringspann South Africa Rossi Gearmotors (Pty) Ltd Rula Bulk Materials Handling SENET SEW Eurodrive Shaft Engineering (Pty) Ltd SKF South Africa Tenova Takraf ThyssenKrupp Industrial Solutions South Africa (Pty) Ltd Timken South Africa (Pty) Ltd Transvaal Rubber Company Voith Turbo Weba South Africa (Pty) Ltd WorleyParsons RSA Zest Electric Motors

BULK HANDLING TODAY

March 2019

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Cover Grade and Thickness Selection Paul Nel (Technical Support Manager)

The current economic climate and the tough recent past have instilled a culture into the mines of saving on operating costs. Even if the country’s economy should boom and mining projects are initiated, mines now have the insight and knowledge of how to operate their facilities more efficiently, limiting operating costs without sacrificing operational reliability.

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ines cannot afford to purchase incorrectlyspecified belting for their installations. Regrettably, more often than not, belting is purchased by somebody in a procurement department, with little or no input from the engineering personnel, or the manufacturer. The risk herein lies in the incorrect belt specification being ordered for a particular application.

The maximum thickness of the top cover is often a figure that the client or engineer produces out of thin air, not paying attention to the long-term implications Normally when a conveyor is designed, the designer will select what he thinks is the best selection for the application. Often the client will not even question such a selection, until it turns out not to work as well as expected. Should the designer be inexperienced or ill-informed, and select the incorrect cover thickness and grade, it could potentially cost the user a lot of money, increasing the total cost of ownership of the installation significantly. For the purpose of this article, it is assumed that maintenance is regularly performed on the installation, and that the belt will actually last the duration of what the covers are designed for, and not get ripped by a chute liner or ruined in any other manner.

Belt strength

What then would be a sensible method of approaching the design of a conveyor belt for a specific application? Any comparison such as this has a single goal, which is to save the user some money. Naturally, the first order of business would be to determine the belt strength. This is done using well-proven design methodologies. However, the selection of the covers in terms of grade and thickness is often not given much thought. The purpose of the covers is primarily to protect the carcass of the belt, which is the main tension member. The top cover will wear over time, mostly due

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BULK HANDLING TODAY

March 2019

to the impact of material onto the belt. Once again, it is assumed that scrapers are set such as to not cause damage to the belt covers and that the only cover wear will be due to impact.

Material characteristics

The first variable to consider when selecting belt cover and thickness, is the material being handled. Such consideration would take into account the lump size, the mass of the material, the abrasion characteristics and the height from which the material is falling onto the belt. In essence this will determine what grade of covers should be used, and a minimum thickness to protect the carcass from impact damage. But that is not where it ends. The maximum thickness of the top cover is often a figure that the client or engineer produces out of thin air, not paying attention to the long-term implications. For instance, a steel cord reinforced belt is made, and the top cover is selected at say 8mm. If the life of mine is 20 years, and such a belt will provide a life of say eight years (barring accidental damage) then one can see that should the belt be replaced twice after the initial installation, when the mine closes, one will sit with a belt only halfway worn, which was an expense, but will provide no income. A selection of a 7mm top cover would have been more sensible. The reasoning behind this is that after 20 years the belt will be almost fully worn, minimising wastage, but furthermore, for a belt of say 1 000m long, 1 200mm wide, the additional 1mm rubber cover will amount to 1,2m3 of rubber per belt, which would have increased the price of the belt and although marginally, added to the power consumed.

Harsh conditions

The selection of bottom cover thickness has similar challenges. For any overland type conveyor, it is beneficial to select an energy efficient type cover. Although the testing of energy efficient type covers is still in the early stages of development, it


COVER STORY

is a reality that power can be saved. Once again, the thickness of such covers should be carefully selected so as to be in the correct ratio of thickness between top versus bottom cover, and to ensure that the user gets the best value for money.

progresses, the material characteristics change. Rubber, being a very ‘live’ product, also changes. This explains why some belts will wear say 2mm in the first three years, and then suddenly wear another 2mm in only one year.

The reputable suppliers in South Africa will query some specifications put to them by the user, while others are so keen on obtaining business, that they are willing to supply the customer with just about anything they ask for without considering the operational conditions. Dunlop has in the past withdrawn guarantees on their product when they realise that the client is exposing it to very harsh conditions. This in turn results typically from a severe lack of maintenance, resulting in the belt being exposed to broken idlers, or running in spillage. A belt running in spillage is likely to wear much quicker than a belt seeing only material load.

Expert advice

Feed chute

As far as the feed chute is concerned, there are two ways of looking at. Firstly, a poorly-designed feed chute will allow material to crash into the chute, accelerating cover wear. A well-designed feed chute, allowing material to get deposited onto the belt at a speed of within around 10% of the belt speed, fed in the direction of the belt movement, is likely to significantly extend the life of the top cover. Secondly then, if the feed chute is well-designed, chances are that a thinner (a minimum cover thickness to protect the carcass), may be used, resulting in overall savings to the operator. Feed chute design is probably the worst culprit when it comes to accelerating top cover wear at the loading point. Very often a new mine will select a particular belt grade and cover thickness, but as mining

Dunlop would strongly recommend that for any critical conveyor belt, the cover thickness and grade be selected by their conveyor experts, as this is likely to result in an overall saving over the life of the installation. Not only will this provide the user with peace of mind that his covers were correctly selected, it will also improve the guarantee conditions.

They are willing to supply the customer with just about anything they ask for without considering the operational conditions As is the case with everything, if there is a degree of control, then it is easy to form an alliance with the user. This implies that the installation is regularly visited and risk to the belt identified and removed. Predictive maintenance and subsequent preventative maintenance can be performed, and spillage removed. It is the opinion of the authors that should mines make a real effort to maintain belting and ensure that belting is correctly selected to begin with, they could reduce their expenditure significantly and achieve higher utilisation figures due to increased reliability and therefore reduced downtime. Rema Tip Top South Africa Dunlop Industrial Products Paul Nel (Technical Support Manager) Tel: (011) 741-2500

BULK HANDLING TODAY

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INFRASTRUCTURE

Addressing Ageing Pipelines Africa faces the urgent problem of having to address its ageing pipeline infrastructure. Aegion South Africa, has a range of solutions to this pressing problem, and has been providing successful project solutions locally and to various African countries, using technology sourced from its US-based majority shareholder Aegion.

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his advanced technology is very effectively combined with Aegion South Africa’s local knowledge, supported by the expertise and experience of its South African shareholder

Robor.

“One of our main focal areas is that of hydro-transportation technology solutions, which involve the transportation of solids in a liquid carrier stream,” explains Aegion South Africa General Manager, Johann Scholtz, adding that hydro-transportation is of particular relevance in the mining industry.

When solids are carried in a closed pipe, environmental concerns such as dust, spillage and noise are eliminated The first international conference on hydrotransportation was held in Coventry in England in 1970 according to the South African Institute of Mining And Metallurgy (SAIMM). Today, just a few decades later, hydro-transportation is becoming an increasingly important consideration for the mining industry - which is under ever greater pressure to conserve the environment. When solids are carried in a closed pipe, environmental concerns such as dust, spillage and noise are eliminated.

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Less maintenance

In addition, hydro-transportation, which is now being widely used throughout the world, is proving to be more cost-effective than other bulk transportation systems such as conveyor belts, long haul road or rail transportation. “An important factor here is that hydro-transportation pipelines require less maintenance than comparable bulk transportation systems,” adds Johann. Much of Africa is chronically short of water. Hydrotransportation also presents a viable alternative to conventional tailings deposition. “In water-scarce regions, the pumping of ‘paste’ tailings cuts water usage and losses dramatically,” he explains. Aegion’s proprietary pipeline technology, the Tite Liner system and its Steel Polypipe spool solution are used in both new and rehabilitation solutions for hydro-transportation. Complete replacement of pipelines are costly and time-consuming, but Aegion’s sister company, United Pipeline Systems develops and provides in-situ polyethylene pipe lining systems for the rehabilitation of existing installations. This solution has proven to be a major improvement over replacement options, especially in pipelines that are in a poor condition. The specialised wear-resistant polymer provides excellent flow characteristics that in some cases


improve the overall system performance. This factor releases significant savings when hydro-transporting over extended distances. Aegion South African shareholder, Robor’s Pipe Systems division, manufactures and supplies a range of steel pipe and customised conveyance pipe solutions and products. “At Aegion South Africa, we are fortunate to be able to tap into this experience and expertise,” says Johann, adding that the company is also cooperating with South African consulting engineers and globally-renowned hydrotransportation specialists.

In water-scarce regions, the pumping of ‘paste’ tailings cuts water usage and losses dramatically transportation projects for more than 20 years. Aegion Johann Scholtz Tel: 011 971 1700 www.l2b.co.za

Right tool for the job

The transportation of corrosive or abrasive slurry materials in the oil, gas, mining, industrial and municipal markets will lead to rapid failure if the correct solution is not implemented from the outset. The HDPE-lined Steel Polypipe system combines the inherent strength of steel with the visco-elastic properties of HDPE to deliver high-pressure capability, structural integrity, resistance to mechanical damage and chemical and abrasion resistance, properties well One of our main focal areas is that of hydro-transportation technology solutions, which involve the suited for use in hydro- transportation of solids in a liquid carrier stream BULK HANDLING TODAY

March 2019

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POLLUTION

Controlling Material Spills A local distributor offers solutions for specific problems at the transfer points of conveyor systems in bulk materials handling on the mines.

ScrapeTec Trading’s German-engineered products have been specially developed for the prevention of dust formation and material spill and for more efficient belt-cleaning at critical sections along the conveyor route and transfer points,” says Ken Mouritzen, managing director, BLTWorld, distributors for ScrapeTec Trading in Africa and the Indian Ocean Islands. AirScrape, DustScrape and SpeedScrape systems, which are

The DustScrape dust filter system is compact and lightweight and complies with most new dust prevention guides

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easy to assemble and operate, form part of the company’s custom-designed solutions service, to meet exact bulk material conveyor project requirements.

Minimising productivity loss

The DustScrape dust filter system, which is used in conjunction with the contact-free AirScrape conveyor belt skirting system, is an energy-free dust emission prevention system. This compact and lightweight system complies with most new dust prevention guides and prevents health and safety issues on-site. This system also minimises product loss by effectively preventing material from being blown into the surrounding environment.


DustScrape consists of a filtering cloth that is installed above the conveyor belt, to retain dust particles created by conveyed materials, while remaining permeable to circulating air. This long-lasting filter cloth, with self-cleaning and dust-releasing properties, is available with different qualities, including anti-static features, for example, in underground mining.

DustScrape consists of a filtering cloth that is installed above the conveyor belt, to retain dust particles created by conveyed materials The DustScrape dust emission prevention system comprises a filter cloth, support arches and skirts, arms to hold the system above the belt and a rubber curtain to eliminate further dust development – all sized to specific requirements. This system is easy to install and can be retrofitted to existing conveyors, for continuous operation and for extended periods.

Selection

Selection of the correct AirScrape size depends on the loading width of the conveyor belt and the required load-free zone of the belt edges. The AirScrape conveyor belt skirting system is installed above the load-free zone and generates the air-intake from outside, into the system. The generated airflow from above the conveyed material then gets filtrated through the filter cloth, retaining any dust particles, which are re-deposited back into the material flow. BLTWorld Ken Mouritzen Tel: (031) 274 8270 Email: ken@bltworld.com www.bltworld.com

BLTWorld’s DustScrape dust filter system, which is used in conjunction with the contact-free AirScrape conveyor belt skirting system, has been developed for the prevention of dust formation

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CONVEYING CONVEYING

Right Compound for the Belt

For a long time, fish stocks out in the ocean were considered inexhaustible. But since the 1960s, the per capita consumption of fish has almost doubled. Nowadays, around half of the world’s consumed fish comes from freshwater and saltwater aquaculture, such as salmon farms out in Norway’s fjords and bays. But even smarter solutions are needed to secure future supply.

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he Ocean Farm 1 fish farm, which investigates biological and technological aspects of offshore fish farming, has been floating out in the Atlantic Ocean since November 2017. The facility has sufficient capacity to breed 1.5 million or 8 000 tons of fish in 14 months. The facility has roughly 20 000 sensors, which allow

Aquaculture operators rely on the particularly gentle and careful transportation of feed

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fully-automated monitoring and feeding of the fish. For this to succeed, the salmon are fed with fish feed. Continental conveyors are used for this process.

Maximum efficiency

Aquaculture operators rely on the particularly gentle and careful transportation of feed. If pressed, fishmeal pellets are put under too much strain, fine particles can become loose and settle on the seabed, resulting in excessive algae growth and water pollution.


Closed Sicon conveyor belt systems by Continental are designed to protect the fish feed. The system remains closed from the pick-up point to the delivery point, preventing fine particles from leaking out and polluting the environment. “Our belts are able to negotiate tight curve radii of less than one metre and in this particular case 13° gradients from where the pellets are stored in the keel of the ship to the deck,” says Continental’s Daniel Grimes.

The facility has sufficient capacity to breed 1.5 million or 8,000 metric tons of fish in 14 months A special compound

One of the biggest challenges in developing this technology was finding the right compound for the belt. “The pellets are made of fishmeal and fish oil, so we developed a rubber compound that is oil resistant and meets the requirements of the fish feed industry. Cleanliness is crucial on- board the ship and at Ocean Farm 1,” says Daniel. Development of the Sicon belts for the Ocean Farm 1 pilot project involved an additional factor in that the salmon farm is out in the middle of the ocean. Its conveyor belts are exposed to wind and weather conditions.

For the workers out on Ocean Farm 1 and the sailors on-board the fish feed ships, the closed system scores points with additional key advantages, one being that it guarantees safety because having oily fish feed on the floor would be a hazard.

Continental Conveyors and Systems Daniel Grimes Tel : ( 011 ) 892 5526 Email: bev@conticon.co.za www.conticon.co.za

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MINING

Maximizing Productivity With Surface Miners West African Guinea is known for possessing the largest reserves of high-quality bauxite in the world which has prompted it to continually expand its bauxite mining sector.

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irtgen surface miners are playing a decisive role in this development process, as many of the country’s bauxite mining operations rely on the company's technology as their standard extraction technique. Wirtgen supplies surface miners in a variety of performance classes for the selective mining of raw materials, such as coal, limestone, bauxite, gypsum, salt and phosphate. In addition to mining, these machines can carry out routing operations for the construction of mining service roads and railway tracks, the rehabilitation of roadways and installation of tunnel floors. The range of applications further includes the precise cutting of trenches and channels as well as surface leveling.

The use of a surface miner also has a positive effect on water management in an opencast mine Consistently high production rates

The most commonly used models for bauxite mining in Guinea are the 2200SM and the 2500SM. The first is compact yet powerful, with a 2.2metre long cutting drum and 708kW of engine power. It is able to cut rock with unconfined compressive strengths of up to 50MPa, ideal for medium-sized

mining operations. The larger model, the 2500 SM, guarantees higher production rates and offers a cutting width of 2.5metre, 783kW of engine power and can economically mine rock with an unconfined compressive strength of up to 80MPa. These surface miners are equipped with a discharge conveyor, minimize such climactic effects by cutting and crushing the material with a cutting drum and placing it alongside the machine (sidecasting) ensuring constant productivity while minimizing the environmental impact. The use of a surface miner also has a positive effect on water management in an opencast mine. The cut surfaces are leveled and can be cut at an angle. This further improves drainage and reduces water seepage into the ground.

More tons per hour

During side-casting, Wirtgen surface miners leave high stockpiles allowing a superb bucket fill. This protects most of the mined material from the rain and allows gravity to drain the piles. The major cost factor in opencast mining is haulage. Mining with surface miners produces level surfaces that serve as stable roadways, supporting the rapid transport of material. This increases the transport capacity of the entire truck fleet. Even the wear on tyres, frame and suspension is reduced thanks to the quality of the roadways, also allowing the use of standard on-highway trucks. As a result, reduced transportation costs allow mining companies to achieve lower per-ton production costs. Mine operators benefit from several cost reductions

Dymot Engineering Company (PTY) LTD Specialist Designers & Manufacturers of Winching Systems Market leaders in conveyor tensioning equipment Take up winches with Overload Protection Gravity Counterweight Handling Braked Capstans Screw Take Ups Hand & Motorised Winches Electrical Control Panels & Systems Sheaves 11 DERRICK ROAD, SPARTAN, KEMPTON PARK SOUTH AFRICA +27 11 970 1920 sales@dymot.co.za www.dymot.co.za

WORLD OF WINCHES

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when using surface miners. Dr. Ing Erik Zimmermann, Product Manager for Surface Miners at Wirtgen, explains, “Our machines allow efficient extraction of material from mines that could not be economically exploited with traditional techniques, creating added value for the industry. For the mining companies, this translates into significant financial advantages for mining and processing.�

Mining with surface miners produces level surfaces that serve as stable roadways, supporting the rapid transport of material

Avoiding blasting

By using surface miners instead of drilling and blasting, raw materials can also be extracted effectively in the vicinity of residential areas, public roads, villages, rivers or other infrastructure eg, pipelines or power lines. It is also possible to mine resources located in buffer and safety zones, maximizing bauxite yield within the concession area, generating significant additional revenue for the mine. In addition, Wirtgen machines enable mining companies to improve material quality. The material size produced by these surface miners is ideal for shipment by truck and rail, eliminating the use of the primary crushers commonly used when drilling and blasting. Wirtgen Email: presse@wirtgen.com, www.wirtgen.com

During the mining process, Wirtgen machines produce level surfaces that serve as stable roadways, facilitating rapid transportation of the mined material. During this process, the leveling system collects and transmits data on the leveling process and controls the cutting depth from the operator’s stand.

K

0 a a

Surface miners can do much more than just extract pay minerals. In Guinea, they are also used to open routes and develop the infrastructure around the mines.

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“THE LINK FOR AFRICAN TRADING”

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BULK HANDLING TODAY

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TRANSNET FREIGHT RAIL

www.transnetfreightrail-tfr.net

BULK HANDLING TODAY

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The Local Manufacturing Expo Aims to:

21 – 23 MAY 2019

Promote local manufacturing

EXPO CENTRE, NASREC,

Demonstrate Southern Africa’s export potential

JOHANNESBURG, SOUTH AFRICA

Provide access to global markets

A Showcase of Southern Africa’s Manufacturing Capabilities Who Will Exhibit?

Networking opportunities Develop public / private partnerships Public / private sector collaborations Identify industry challenges and opportunities for growth

Manufacturers across a variety of sectors, including:

Agriprocessing

Automotive

Business Process Outsourcing

Capital Equipment

Chemicals

Construction

Engineering

Food and Beverage

Furniture

ICT and Electronics

Metals

Mining

Plastics

Textiles/ Clothing/ Footwear

Transport

www.localmanufacturingexpo.co.za In association with:

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Endorsed by:

BULK HANDLING TODAY

Implemented by:

March 2019

Brought to you by:


th

MINING

Large finds in DRC’s Kasai River The iDredge commissioned by Africa Resources and designed and fabricated by Imilingo Mineral Processing has produced 14,1 carats from 1 200 kg of alluvial/gravel deposits in the Kasai River in the first test run.

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homas Häggkvist, the CEO of Africa Resources AB, approached Imilingo Mineral Processing in October 2016 for a possible solution to the cumbersome and hazardous diving conditions involved in alluvial diamond recovery. “Modern mining techniques and sorting technology has been severely lacking in alluvial diamond mining and the iDredge has certainly delivered in injecting some much needed technological advancement in the industry,” comments Thomas.

Technology to change mining game

Jaco Prinsloo, MD of Imilingo, worked with a team of engineers to design and fabricate the iDredge. Jaco asserts the ingenuity of their design is transforming digital automation in the diamond mining game. “The vessel consists of a floating platform connected to two pontoons. A Dragflow 60 Kw submersible pump with high-depth compensators provides suction and allows particles up to 60mm in size to be pumped through the 150 NB pipe. An onboard rotatable crane submerges the pump and is there to make the pump accessible for maintenance purposes. "A 150 KVA diesel generator supplies power for the iDredge and the mined material is fed onto a double-deck vibrating screen. Both generator and screen remain on the riverbank. The iDredge has the unique advantage of being collapsible for transport, making it feasible to reach remote destinations.” The iDredge began the journey from Imilingo’s Centurion fabrication facility in December 2017.

Road transport to the port at Durban took a week and after 17 days at sea, the two 40ft and two 20ft containers arrived at the port of Matadi on the West Coast of the DRC. “Much of the infrastructure in the DRC, especially the road network, is extremely eroded which necessitated a change in the site where the iDredge would be used,” Jaco says.

iDredge assembly

A technical team from Imilingo Mineral Processing accompanied the mining team on their journey to help assemble the iDredge. The machine was assembled in an excavation next to the river and the same excavator did duty as a crane for some of the heavier components.

Much of the infrastructure in the DRC, especially the road network, is extremely eroded which necessitated a change in the site where the iDredgeT would be used When assembled, the excavation was flooded and the iDredge entered the river. Cables were linked to the opposite shore to winch the vessel into position in the centre of the river. “Rivers in the DRC flow very fast and we had made sure that two sturdy trees on either side of the river acted as anchors for the iDredge cables,” Jaco explains. After the Imilingo commissioning team left, the local site team continued operations and cleared the river bed of sand overburden before reaching the diamond gravel. The first diamond gravel was pumped on 29 August 2018 and then washed to recover the company’s first diamonds. The test run shows great potential for Africa Resources’ operations in Tshikapa and all parties are immensely optimistic at the prospect of diamond recovery in the area. “The test run showed bags of promise with 14,1 carats from 1 200 kg which would equate to 1 175 cpht based on the isolated test," Jaco concludes.

Imilingo Jaco Prinsloo Tel: (012) 880-1559 Email: jaco@imilingo.com www.imilingo.com

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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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SCREENS

A double deck screen leaving Kwatani for the end user

Lower Cost of Ownership Kwatani’s custom engineered screens are now in some of the largest mines, and many customers have standardised on them to ensure lower cost of ownership and high performance, according to general manager of sales and service, Jan Schoepflin.

The assembly area packed with screens waiting for final testing prior to being despatched

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Piecing together your success.

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SCREENS

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hile screening in heavy minerals is Kwatani’s stronghold, the company has moved into coal, supplying the country’s leading coal producer with no fewer than 45 items of large screening equipment, including outsized 4,3 metre wide units. Other recent coal-related orders included run-of-mine screens for a medium-sized coal mine in Mpumalanga. Competitor equipment was replaced by custom designed screens with optimised deck angles which significantly increased tonnage. The positive results achieved with the Kwatani equipment also led to additional orders for the mine’s expansion.

Zinc, iron and platinum

Kwatani was contracted to supply all the screens for the world’s largest zinc mine. At Africa’s largest iron ore mine, the company has recently completed two projects, renewing existing equipment A scalper screen for the coal mining sector going through the testing process with up-to-date solutions and replacing 24 items of competitor equipment. The platinum sector is also keeping Kwatani busy, not just in South Africa but in Zimbabwe too. A recent turnkey solution focused on the platinum by-product chromite, where the company supplied a complete solution including feeders, dryers and screens to treat chromite of 45 micron size at 15 tonnes per hour. Kwatani Kim Schoepflin Tel: 011 923 9000 Email: service@kwatani.co.za www.kwatani.co.za A row of screens in operation in the iron ore mining industry A 4,3 metre scalper screen ready for despatch to the customer

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ROAD-RAIL

Emission-free Flexible performance Vollert is now marketing its Robot Vlex with articulated steering. In addition to permanent use in railway depots, the emissionfree, battery-operated and compact Vlex is suitable for both temporary and permanent use.

T

he one-man operated radio-controlled vehicle switches from track to road and back again, and despite its compact dimensions, it is suitable for manoeuvring loads of up to 300 tons.

Its vehicle geometry with articulated steering and four individually-controlled wheel hub motors make it extremely agile and economical. This ensures a turning radius of 7.2 metres.

Rental option

”Some customers opt to rent the Vlex,” says Jürgen Schiemer, Vice President at Vollert. For example, SSB in Stuttgart used the compact Vlex for six months to move trams onto newly erected sidings until final installation of overhead lines. "With its small dimensions and a dead weight of 4.5 tons, the Vlex is easy to transport and can therefore be quickly employed anywhere."

The one-man operated radio-controlled vehicle switches from track to road and back again, and despite its compact dimensions, it is suitable for manoeuvring loads of up to 300 tons Permanent use

At Kämmerer Spezialpapiere in Osnabrück, a Vlex creates the connection between two halls. In doing so, paper rolls are protected from the weather in a closed wagon and transported to the dispatch hall. Kämmerer has reactivated existing track systems, but also uses the tarred road surface in

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front of the halls for truck traffic. The road-rail Vlex vehicle is optimally suited to the existing conditions and takes over the manoeuvring task of two trucks in a continuous change operation.

E-Robot: emission-free and quiet

In addition to the compact Vlex, Vollert has an entire range of economical shunting and transport systems for secondary and connecting lines on offer. This ranges from stationary cable systems, to heavy-duty transfer cars, transport vehicles and even stationary shunting vehicles. “We are currently experiencing a high demand for electric drive technology. These are just as flexible as diesel engines, but without noise and exhaust emissions. A stop-and-go situation is the rule during loading and unloading. In contrast to diesel vehicles, there is no noise or emissions during breaks, and yet the torque is available immediately," Jürgen says. To be able to offer the optimum solution for track applications, Vollert engineers are working on the development of a battery-diesel combination drive. This combines the emission-free advantages of the battery to be used in train stations and loading stations and higher speeds while allowing for longer distances. Vollert Jürgen Schiemer E-Mail: infovollert.de www.vollert.de

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Your boutique business destination Surrounded by lush gardens in the hub of Johannesburg’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.

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BELTCON 19

Splice Failures Resulting from Rubber Compound Incompatibility

A

André van Staden

Rema Tip Top South Africa (Pty) Ltd/Dunlop Industrial Products

n ailing economy has forced users of conveyor belting to find ways in which to extend the life of the belt. This can be achieved, but only if the conveyor system is well maintained and operated within original design parameters.

In the recent past, a significantly aged belt was replaced by a new belt, thus virtually eliminating the risk of failure. Now, however, taking into account the cost of belting and the lack of capital in many companies, every last bit of life is squeezed out of a belt. Due to these factors it has become quite a common practice to replace only severely damaged portions of belt. The example in this paper considers new belting supplied for a particular overland conveyor and installed 11 years ago. Recent external damage called for a length of belting to be replaced, and the splices related to the new piece of belting failed in quick succession. This occurred despite tough quality assurance measures being applied. The task of splicing the belt was transferred to a second reputable splicing company, yet similar results were produced.

General

Figure 1. Hot vulcanising press

The question arises as to whether the current splicing compounds used are compatible with compounds used during the manufacture of the original belt 11 years ago. This is an ongoing investigation and further testing and research is required. This paper explores several areas of interest: • Advances in rubber compound development over the last 15 years. • Rubber deteriorates over time, so that even if an identical compound to that used in the original is applied, the original may have matured to the point of no longer being compatible with a fresh batch of compound. • Identification by the splicing company of the compound, and management of the process to ensure that some incompatible, cheap, imported compound is not used to splice a belt, potentially risking production hours and safety. • Modern advances in conveyor belt splicing.

Figure 2. Piano wire steel cord stripper

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High security welded mesh

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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

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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

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BELTCON 19 • Conveyor belt splice management guidelines. • Material compatibility testing guidelines.

Advances in rubber compound development over the last 15 years

In order to understand the compounding of rubber, ingredients of the rubber compound must be known. 1. Polymer: 100 pph. Natural or synthetic. 2. Filler: 30—60 pph. Most common is carbon black. 3. Antioxidants: 1—3 pph. Helps protect the compound from high temperatures while in use and during mixing. 4. Antiozanants: 1—3 pph. Protection against ozone attack. 5. Oil: 5—30 pph. Assists in the incorporation of all dry components during the mixing process. Changes mechanical properties of final product (hardness). 6. Curatives: 5—10 pph. Most common is sulphur. Creates crosslinks between rubber molecules with the addition of heat. In response to the ever increasing demand for natural rubber, it has become crucial to explore other avenues of supply. Natural rubber is a limited resource and in the near future the demand will outstrip the availability. Rubber compounders are constantly attempting to improve the properties of rubber compounds. It is for instance, now possible to replicate the same properties of natural rubber using synthetic rubber. By the use of certain additives and fillers, the mechanical and chemical properties of rubber can be changed. Aramid fibers for instance, change the indentation rolling resistance of the compound. It is, however, a matter of give and take. With the addition of one compound to improve a particular property, it might very well change another property for the worse, such as elongation or tear resistance. Constant research has made possible a fire retardant compound with low abrasion loss characteristics, in the region of 130 mm3. The determination of abrasion loss is described in SANS 4649/ISO 4696, Rubber, vulcanized or thermoplastic – Determination of abrasion resistance using a rotating cylindrical drum device. Test Method B – Rotating test piece. Fifteen or even five years ago such low values were totally unheard of. The continuing re-development of compounds could be the very reason for the failures or incompatibility of modern com-

pounds with compounds used in the manufacture of conveyor belting 10 to 15 years ago. Some additives in a compound can be changed, or totally different additives used. The end result is a compound with the same properties as the original compound of 15 years ago without the two compounds being at all compatible. Changes occur within the compound during the aging process, significantly changing the structure of the compound. Therefore, even the same compound containing exactly the same additives will not be compatible and will result in a failed splice.

Deterioration of rubber over time – aging

Deterioration of rubber over time, meaning that even if a compound identical to the original is used, the original may have matured to the point of no longer being compatible with a fresh batch of compound.

Polymer Degradation

Polymer degradation is the change in the properties of a polymer: tensile strength, colour, wear resistance etc. This could result in various factors affecting the polymer or compound. Heat, light and chemicals may affect changes, and typically such changes are undesirable.

Photo Induced Degradation – UV Damage

Most polymers are susceptible to this type of degradation which is visible as discolouration or cracks in the compound.

Thermal Degradation

Thermal degradation can be defined as a compound's loss of mechanical properties as a consequence of exposure to heat. The links between the polymer chains are broken and begin to react with one another, thereby changing the properties of the polymer or compound. Thermal breakdown could result in the generation of a variety of hazardous products such as carbon monoxide, ammonia and hydrogen cyanide, some of which may be toxic or flammable. The specific materials are dependent on the compound mix, additives used, specific temperature of exposure, time of exposure and environmental factors.

Ozonolysis

Ozone in the air attacks double bonds in rubber chains, natural rubber, poly-butadiene, acrylonitrile butadiene rubber (NBR) and styrene butadiene rubber being most sensitive to this attack. Ozone cracks are likely to form in products under tension, however, the critical strain is very small. The cracks always occur at right angles to the strain angles. Through the modification of the rubber compound with the addition

Figure 3. Knife steel cord stripper components

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BELTCON 19 of anti-ozonants before the vulcanisation process, cracks could be retarded or even prevented. This is normally a type of wax that is formed and can be seen as a waxy substance on the covers of the belt owing to the blooming of the wax.

• Is the company affiliated to a belting or compound manufacturer?

Galvanic Action

• Does the company manufacture their own splicing materials?

It is possible for a polymer to degrade due to galvanic action. This is when two dissimilar metals in close proximity immersed in salt water cause one of the metals to corrode. In 1990 it was found that carbon fibre reinforced polymer (CFRP) can corrode under the correct conditions. This was described as the 'Faudree Effect'. It is perhaps the reason for the breakdown in the bond between the bonder layer and covers of certain steel cord belts, as the two compounds contain carbon and other metals with different characteristics. This matter will be the topic of future research.

Identification and managment of a splicing company

One of the most important factors in achieving a successful splice is the selection of a reputable splicing company and the management of this company. When selecting a company to perform splicing, some of the factors or criteria for selection should be:

• Is the company a reputable company with traceable references?

• Do they have access to testing facilities in order to perform compatibility testing and splice analasis? • Is the company involved in material R&D such as materials and processes? • Does the company have a quality procedure in place to ensure traceability of splicing materials as specified by SANS? • Do they have recognised, auditable procedures and processes? • Are their tools and equipment in good condition? • Do they have a skilled, trained, workforce? To ensure that the most reliable and safe splices are performed, the selected splicing partner must be managed. Even if the selected company complies to most or all of the selection criteria, some form of management is required. The issues listed below are important and should be seen as the minimum management input from the principle company. This is specially important in the replacement and installation of productioncritical belts. Most of the criteria for the required documentation to manage the splicing company efficiently is contained in the relevant splicing specifications. • Insist on adherance to a specific splicing procedure, either the hiring company procedure or any of the recognised international procedures such as SANS, DIN etc. • A quality control plan (QCP) should be submitted and signed off by the partner company before commencement of splicing. Witness and hold points should be agreed upon up front.

Figure 4. Knife steel cord stripper

• Compatibility of suggested materials with the principle's belt must be proven before commencement of splicing. Recent test results must

Figure 5. Preformed splicing material

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BELTCON 19 be available, not older than 12 months. These results should indicate the compatibility of the splicing company’s selected splicing material and the principle's installed conveyor belts, irrespective of manufacturer. Ideally, these test results should show compatibility to all major belting manufacturers' products. • Request that a test splice be performed on site and analysed before any critical splicing takes place. There may be a cost involved in this, but it is well worth managing this potential risk. • Request regular audits of splicing on site. The principle should be present at this stage to verify that all procedures are followed. • A safety file listing crew and equipment must be on site during splicing. This file should contain as a minimum: • Splicing specification to which splice is peformed • QCP signed by principle and contractor • Works instruction of splicing company showing all steps and procedures • Equipment/calibration certificates for all equipment

• Splicing quality documentation indicating material traceability • Splice design, approved by principle • Any other documentation as requested by the principle, such as safety information etc. • Qualifications of personnel performing the splice.

Modern advances in conveyor belt splicing

During the last decade, significant advances have been made in the field of splicing that have resulted in more reliable, cost effective splices with the shortest possible downtime. Vulcanising presses have become more efficient and advanced, offering better control over the splicing process. Heating and cooling times have been greatly reduced.

Tools

The introduction of specialised tools makes possible a reduction in the preparation time, while increasing the accuracy and quality of splices.

Splicing Material

Splicing material development is in a state of continuous development, searching for the ideal splicing material compatible with most compounds, and which will still achieve the required splice efficiency. Compound delivery for steel cord reinforced belt splicing has seen a change with the introduction of preformed and composite splicing compounds. Preformed compound does away with the need for bonder rubber noodles or strips inserted between the cables of a steel cord splice. With the correct preformed bonder rubber, the cords can be laid in the correct position more accurately and faster.

Figure 6. Composite steel cord splicing material showing cover and bonder composite.

Composite splicing compound is assembled in the factory, similar to belt production. The bonder compound and the top or bottom cover compound is combined to splice specification and delivered to site in kit form. This eliminates the possibility of dust and other contaminant ingress between covers and bonder compound during assembly on site or in the workshop.

Figure 7. Splice measurement matrix as per SANS

Figure 8. Typical representation of a splice on a steel cord reinforced belt, by means of magnetic flux leakage scan

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BELTCON 19 Conveyor belt splice management guidelines To ensure the safe and efficient operation of any installation, a splice management program should be established. This can be done in conjunction with the splicing company or an external service provider with the relevant expertise. Splice monitoring is not an exact science and it is possible for splices to fail at any time without any prior signs of deterioration. All splices should be numbered in accordance with the relevant standards in order to better keep track of splice age and life. Splice measurement should be done at intervals mutually agreed upon. Visual inspection and measurement of splices should be recorded and analysed for any abnormalities.

Splice measurement matrix as per sans

a. Permanently embossed marks shall be placed on the inside four corners of the splice on the bottom cover (see figure below).

∑4 dim to remain within 1 % of original value.

b. The sum of the dimensions shall not change by more than 1 %. The base line initial measurements shall be made on the low tension return side of the conveyor when the belt is under tension at a recorded datum point and always re-measured at the same datum point and under the same tensioning conditions.

In the event of steel cord reinforced belting being used, a baseline scan should be done upon completion of splices to verify correct layout of cords and splice integrity. This can be done using either X-ray or magnetic flux leakage scanning. Regular follow-up scans should then be performed at agreed intervals. The follow-up scans must then be compared to the baseline scan, checking for any changes or deviations from the original. X-ray scanning is however, not cost effective and does have some safety concerns linked to it. With the recent advances in the accuracy of magnetic flux leakage scanning it is possible to obtain a very accurate representation of the splice and it is possible to determine small deviations within the splice. The systems can also be permanently installed on the structure with the added benefit of offering a full belt scan to determine the condition of all the cords within the belt. In the magnetic flux leakage scan image, the cords are magnetized and any leakage in the magnetic flux is detected by sensors mounted in a sensor array. The image in Figure 8 is of a two-stage splice showing no deformation in the splice alignment or stray and damaged cords in the splice area.

d. Should the tensioning conditions change, a new set of base line dimensions shall be established.

Further research is required on the effect of positive and negative bending of splices, different types of splices, including the effect of the frequency of bends on a splice, for instance at the head and snub pulley, or from a high tension snub pulley into a drive pulley. The specifying of a minimum relaxation distance between two bends in opposite directions should be investigated and documented.

Scanning

Material compatibility testing guidelines

c. Initial measurement to be done by splicing constructor.

Steel Cord Reinforced Conveyor Belting

Compatibility of splicing material and belt is assessed by testing the adhesion of the splicing material to the aged belt cords. For this purpose the preparation of an H-block test piece is required. The H-block consists of three cords vulcanised in a splicing material rubber matrix. A minimum of four H-blocks are required for testing.

H-block construction

Consider the leading belt as A and the trailing belt as B. Cords must be stripped in accordance with procedure for the preparation of a splice.

Assembly and cure

Two H-blocks are constructed by using cords from belt A either side of a cord from belt B. (A,B,A,B,A) and two H-blocks constructed by using cords from belt B on either side of cord from belt A (B,A,B,A,B). Figure 9. Typical representation of a splice on a steel cord reinforced belt, by means of a X-ray scan

After curing, the H-blocks should be left overnight to stabilise. Standard pull-out testing is then performed.

Figure 10. Conveyor system indicating positive and negative bends in short succession at pulleys A-C and at A-A

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BELTCON 19

Figure 11. Din dynamic splice testing equipment


BELTCON 19

A minimum pull-out figure would be 12 x cord diameter. Anything less, and a splice design may not have a sufficient safety factor if designed on 8 x cord diameter, normal. A result of less than 10 x cord diameter pull-out (expressed in kN/m) means rejection of the splicing compound. When the H-blocks have been tested, the mode of failure is noted, i.e. bonder to bonder, or cover to bonder. Cover to bonder is preferable as a greater proportion of splice strength relies on bonder to bonder adhesion. In addition, two H-blocks (one A,B,A and one B,A,B), must be subjected to dynamic cyclic testing to determine the compound’s resistance to fatigue. The set points would be 36% and 3.6% of the actual achieved pull-out test results. Some mining companies insist on 7 000 cycles minimum, with no evidence of cord pull-out.

Figure 12. H-block mould

The cyclic blocks are again tested in the tensile test apparatus to determine any fall- off compared to the original lab-built H-block pull-outs. The figures should be about 95% minimum. Anything less must be rejected.

Plied Belt Testing

The same type of testing is applied to plied belts, using whichever compound is applicable. A lab pad is constructed containing all plies, and subjected to adhesion tests after allowing stabilisation. Results must be at least equal to new belt adhesion test results. Extrapolation should result in a figure of approximately 65% of full belt strength when testing a four-ply belt if a reduced stepped splice is built.

Figure 13. Splicing compound in mould

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BELTCON 19 Conclusion

Rubber, as do humans, ages. How this aging process is managed may not be an easy and straightforward task. To ensure the safe and efficient operation of any spliced conveyor belt, it is important to ensure that the best possible materials and the best matched materials to perform the tasks are used, in conjunction with good practices, correct and functioning equipment, and operation by qualified and competent personnel. If the splice process is well managed, especially on steel cord reinforced belting, it should be possible to expect such a splice to last the life of the belt. If splices are regularly monitored for deterioration, early detection of any kind of damage can be managed, and possible losses due to a splice failure minimised by performing preventative maintenance.

Figure 14. H-block assembly

This paper was first presented at the Beltcon Conference in 2017. Copyright is vested with IMHC. www.beltcon.org.za

Figure 15. H-block assembly

Presented papers at Safecon 1 – “Splicing Methodology” and Beltcon 18 – “Technology and conveyor belting.” André van Staden Dunlop Industrial Products (Pty) Ltd Tel: (011) 740-2500/2603 Mobile: 083-283-7806 Email: Andre@dunlopindustrial.co.za

Figure 16. Completed H-block

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Demolishing with high-grade steel

For over three decades, steel company SSAB has delivered steel plates to England-based Kocurek Excavators, a company specialising in the manufacture of demolition equipment. SSAB helps family business, Kocurek Excavators in Ipwich, England to continually push the boundaries on behalf of their worldwide-customers. The extreme forces needed when tearing down buildings with demolition equipment up to 70 metres high is supported by SSAB’s

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A tamper-proof vibration-warning indicator paste that can improve safety and reduce inspection time across a number of industries is now available from Bearings International (BI).

Applications for Dykem Cross-Check Torque Seal range from haul trucks to head gaskets in vehicles, gearboxes, and even conveyor belts. BI Product Manager Richard Lundgren explains, “When a piece of equipment vibrates, whether it be a car, airplane, crane,

or water supply pump, there is always the chance that the torque of any nuts and bolts may loosen. "With Dykem Cross-Check Torque Seal, the artisan literally draws a line of the paste from the bolt head and along the threads of the screw, once perfect torque has been achieved. At the next inspection, the artisan checks to see if the brightly-coloured mark is still in alignment. If not, action can be taken there and then on that specific bolt,

Werner Baller, founder and chairman of Weba Chute Systems, has been inducted into International Mining’s Technology Hall of Fame. The accolade marks a major achievement for Werner and the company he has developed since 1983. Born in West Germany, he studied

instead of having to retighten all of the bolts, thereby speeding up the process dramatically and reducing the possibility of any loose bolts being missed." The indicator paste is supplied in a tube, and comprises a gel-like substance. This is dry to the touch in one to two hours, and fully cured in 24 hours. Bearing International, Richard Lundgren Tel: (011) 899-0000 Email: info@bearings.co.za www.bearings.co.za

ceramic engineering before coming to South Africa in 1965. With 45 years’ experience in mining and engineering, and 27 of those in transfer chute systems, he has developed nine patented products. Perhaps the most successful of these has been his Weba Chute System, which he developed after a comprehensive study of conventional chute design. Taking a scientific and innovative approach to the dynamics of bulk materials at transfer points, the Weba Chute System presents a streamlined and cost-saving alternative. It also delivers higher levels of occupational health and safety. Based on the lined ‘super tube’ or cascade system, the lower layer of material in the product stream moves in a tumbling motion, rather than sliding. This reduces wear, with the lip often remaining completely covered by material and therefore never needing to be replaced.

Werner Baller, founder of Weba Chute Systems

Weba Chute Systems pioneered the engineered transfer point and it was through the company’s ability to view it in a completely different way that industry is today able to control the flow of material with all the benefits that this brings

Weba Chute Systems Mark Baller Tel: (011) 827-9372 www.webachutes.com

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New excavators get let out of the cage The Cat range of Next Generation mini hydraulic excavators has been expanded with the addition of two new models in the 7-to-10-ton category. The new models provide a selection of basic configurations, allowing customers to choose the machine that works most efficiently in applications routinely encountered. As with all Cat mini excavators, the new models feature heavy duty main structures, fuel efficient engines, load sensing hydraulics, spacious cabs, and the exclusive Caterpillar stick steer system. The overall design goal for these models is to ensure optimum value for the customer in terms of performance, operator experience, serviceability, and affordability. The new 307.5 weighs from 7 532 kg to 8 233 kg depending upon configuration. It is a standard tail swing model with a fixed boom, powered by a Cat C2.4 turbo diesel engine rated at 41.7 net kW. It can be ordered with a standard

stick delivering a 4 107 mm dig depth or a long stick that increases the depth by approximately 560mm. Also new to the range is a 310 weighing between 9 601 kg to 10 182kg, and featuring a fixed boom, standard tail swing, and twin blade cylinders for handling heavy duty dozing chores. This machine uses the Cat C3.3 diesel engine rated at 52.4 net kW (70.3 net hp) and has a dig depth of 5174mm. Intuitive controls include a LCD monitor that provides easyto-read machine information and features a jog-dial for easy navigation, including setting personal operating preferences. For added convenience, a standard control-pattern changer allows operators to quickly adapt the machine to their favoured joystick movement. A machine security system is standard, available as key with passcode or push-to-start with fob. The machine can also be Bluetooth-enabled through the radio. Cat, www.cat.com

Stirring up the rental market The most popular rental machines available from Bobcat Rental at the moments are its skidsteer loaders, with Bobcat having the largest rental skidsteer fleet available in South Africa. The rental division also offers an extensive range of attachments, from road sweepers to trenchers to tar planers. All of these attachments are interchangeable, making this skidsteer loader a versatile and highly-efficient piece of construction equipment. Another highly adaptable rental machine is the Bobcat backhoe loader, for digging to trenching, breaking, or general materials-handling. This is a very reliable machine that s in high demand, with 11 in the national rental fleet at present. The Bobcat Rental division procures new machines from Bobcat Equipment South Africa, and older machines are retired from the rental fleet in good working order, whereupon they are made available for sale, promoting the second-hand sales division in turn. “All our rental machines are serviced and repaired at our workshops at each branch to ensure maximum uptime, while equipment is replaced to ensure business continuity for our clients,” says Bobcat Rental General Manager, Vanessa Koszulinski. “In dealing with so many different industries and customers, we find that our plant being fully maintained and serviced within the ambit of our rental agreements ensures huge savings for our clients, as well as assisting them in reducing their overheads and mitigating business risks,” Vanessa concludes. Goscor Debby Marx Email: dmarx@goscor.co.za Web: www.goscor.co.za

Telehandler goes electric Battery Power Industries (BPI), battery driven mining vehicle specialists, has provided the battery drive system for Manitou, Southern Africa’s first electric telehandler. BPI designed and implemented the conversion of the telehandler from a diesel driven system to a fully electric system using Lithium Ion battery technology. The MHT-790E electric telescopic handler has a lifting capacity of up to 9 tons and a lifting height of up to 6.84m. The machine is powered by a LiFePO4 (Lithium Iron Phosphate) battery, known to be one of the safest battery chemistry compositions for its thermal and chemical stability. According to Calvin Coetzee, BPI Managing Director, the additional advantages of using this type of battery include its low cost, non-toxicity, the natural abundance of iron, safety characteristics and electrochemical performance. “In the MHT-790E electric telescopic handler, all of these advantages culminate in a machine with zero emissions and far less heat being produced, which protects the health and safety of those working in confined areas. It also has a battery life expectancy of 3 000 cycles and continuous battery shift time of 8 hours, This combined with a high speed charging time of 90 minutes or on-board charging time of 8 hours ensures an uninterrupted work shift,” he concludes. Battery Powered Industries Email: info@bpi.works www.batterypowered.co.za

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Cranes build biggest dam in Namibia Concord Namibia (Plant & Crane Hire) has played a role in the completion of the Neckartal Dam project, the largest water-storage dam in Namibia at about 960 million cubic metres. It supplied a 220t and a 550t crane to assist Italian contractor Salini Impregilo with construction of the 80m-deep dam, with a crest length of 518m. The 220t crane’s main function was to install trash racks and roof beams for the inlet tower facing the water side of the dam. Water enters the inlet tower through the dam wall into the turbine room, where it generates hydroelectricity, explains Concord CEO, Francois Smith. While still inside the partially-completed inlet tower, complex rigging and lifting was required

to position the 22t concrete roof beams for the tower. With the final four beams directly on top of the crane, the crane had to be re-positioned outside the tower, on a narrow dam wall, and the beams lifted up and over the tower walls in order to place the remaining four beams. Several computerised rigging studies were carried out to ensure a safe and successful lift of every beam. The 220t crane was then relocated to the river or ‘dry’ side of the dam, where it was used to dismantle two tower cranes that had been deployed over the four-year construction period. In addition, a 550t crane was used to dismantle an 8 metre high tower crane, and re-erect it on top of the dam wall. The 550t crane was also responsible for dismantling the conveyor-belt systems supplying concrete from the batching plant to the dam wall. Concord Cranes Francois Smith Tel: (011) 805-8071 Email: francois@concordcranes.com Web: www.concordcranes.com

Automated laboratories market The market for automated laboratories is growing due to a combination of high exploration activity and an increased focus on productivity, automation and digitalisation. IMP, a company specialising in automated laboratory solutions for the mining industry has a strong foothold in Australia and South Africa. Its solutions complement the products FLSmidth offers for quality control and optimisation for the mining process.

The acquisition includes over130 IMP employees, including the managing director, Boyne Hohenstein. “Knowing your ore characteristics from the mine, all the way through the processing plant, is of increasing importance in mining as declining ore grades make it necessary to increase productivity by process optimisation. We see a strong match between some of our digital initiatives in FLSmidth and

IMP’s automation solutions that will help miners get better data on their ore and assist in optimising the processing. With this acquisition, our flowsheet of laboratory solutions within mining and minerals processing is complete, and this will be of great value to our customers,” says Manfred Schaffer, President Mining, FLSmidth. FLSmidth, Sofie Karen Lindberg, Email:skl@flsmidth.com, www.flsmidth.com

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High performance motors for demanding environments Goscor Earth Moving Equipment has added the SMG200 motor grader to its line-up. The motor offers maximum power and superior levelling performance, without compromising on safety and comfort. Another feature is that the cabin has been optimised for 360° all-round visibility and easier access to controls, enhancing operator comfort and boosting productivity. The cabin has also been engineered with a 75 dB Silent Mode for noise cancellation. A load-sensing hydraulic system ensures high-precision motion control. The system regulates the flow volume automatically according to the load, conserving engine power and reducing fuel consumption. Other key specifications are a blade length of 4.27 metres, an operating weight of 16 920kg and an overall length of 8.89m. What makes the SMG200 ideal for arduous African operating conditions is the durable exterior, with strong slewing ring bearings providing added strength for

improved serviceability. Ease of maintenance is critical, and here Sany has positioned all filters centrally for quick accessibility. A well-designed handrail makes it easy to carry out routine checks.

Goscor Debby Marx Tel: (011) 230-2600 Email: dmarx@goscor.co.za www.goscor.co.za

Even loads thanks to hydraulics Hytec recently commissioned the R10million hydraulic system it supplied for the new bulk handling equipment installed at Assmang’s Black Rock Mine Operations in the Northern Cape. Black Rock

At the load-out station, Hytec’s hydraulic systems extend from the control of the exit gates of the loading bin, across the weigh flask that divides the load into batches that are then transferred into the wagons below.

This bulk handling system includes two stackers, a bucket wheel reclaimer and a rapid load-out station, each automated using Hytec’s proportionally controlled hydraulic systems assembled from Bosch Rexroth technologies.

Up to 600ℓ/min of hydraulic flow is required at specific stages of the load-

out station, which also needs to deliver precise distribution control within each wagon with strict tolerances. Hytec Klaus Marggraff Tel: (011) 975-9700 Email: klaus.marggraff@hytec.co.za www.hytecgroup.co.za

“The proportional control achieved by the system delivers precise remote flexibility in adjusting, varying and optimising the load handling characteristics of the machinery to accommodate any changes in the nature of the material,” explains Hytec System Sales Manager, Klaus Marggraff. The two stackers, manufactured by ELB Engineering Services, were equipped with 7.5 kW hydraulic systems that will control the stacking of manganese ore in the stockyard in various grades of material. The bucket wheel reclaimer was supplied with a 45 kW hydraulic system and includes dual luffing cylinders.

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The hydraulics ensure that the loads are evenly and accurately distributed, maintaining the integrity of the axle load to strict tolerances

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An ideal wear solution Chromium carbide (CrC) overlay plate from wear engineering specialist Rio-Carb is a great wear solution for a range of applications, from truck beds to dozer blades, shovel buckets, front-end loaders, and dragline buckets. The plate features a standard smooth surface with relief cracks, a ductile and workable backplate, a quality-controlled fusion zone, and a hard CrC overlay. It

forms the basis of an engineered truck bed liner system that offers significant cost of ownership and return on investment benefits for customers, Rio-Carb General Manager Sias Suurd explains. Available in a hybrid liner package, the system greatly improves the wear life of truck beds, due to the fact that the plate wears down at a uniform rate, which means it is less maintenance-intensive,

as well as increasing productivity dramatically. Other advantages are that the system has been designed to reduce welding, and can be customised in terms of its overall weight. Rio-Carb Jabu Mlambo, Tel: (011) 011-6111 Email: jabu@riocarb.co.za www.riocarb.com

Not your average crane JCH Platforms has extended its crane hire portfolio with the addition of units ranging from 12 to 28 metres and the ability to lift from two up to nine tons. Each crane has its own design and unique capabilities, facilitating use by customers in varying applications. “One of our more popular smaller units is the ManGo 12 access platform, with a working height of 12 metres,” says Ramona van Rensburg, sales representative at JCH Platforms. “Unlike most access platforms, this unit is designed with the same access capability as a scissor lift, making it a lightweight machine for both construction and industrial markets but with the advantage of an articulated boom to overcome any vertical restrictions that a standard scissor lift would have.”

on the machine is fitted with a retraction pump that absorbs any residual oil in the system providing a much smoother operational experience. The Safe Man System (SMS) protects operators by minimising the risk of crushing. Another popular range is the ATJ line of access platforms which includes the 180ATJ with an 18 metre reach, the

200ATJ with 20 metre reach and the 280TJ reaching 28 metres with an access platform with a 4 metre telescopic jib that redefines the up-and-over capabilities of this type of machine. Johnson Crane Hire Peter Yaman Tel: (011)11 455 9242 www.jch.co.za

Some of the improved safety measures that come from the Manitou range include galvanised steel baskets making them less likely to corrode and profiled mesh floors for better traction and Each unit has its own special design and unique capabilities facilitating use by customers in varying safety. The hydraulic pump applications. BULK HANDLING TODAY

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A logical merger Konecranes and Demag have recently merged into one legal entity under the new name of Konecranes and Demag. Following Konecranes’ acquisition of Demag worldwide just over two years ago, South Africa was at the forefront of merging the head offices as well as the eleven branches around the country. The merger of the two global crane companies brings together considerable technical expertise and a wealth of experience going back centuries. “We have been working locally on simplifying the corporate structures of both businesses in an effort to align our brands and product labelling, as well as streamline our efforts and operations,” says Emil Berning, MD of Konecranes and Demag. Konecranes and Demag Emil Berning Tel: (011) 898 3500 Email: infoza@konecranes.co.za.

A 52metre long, 65ton 'desludging bridge' leaves Demag's Boksburg factory

Bearings keep the drinks flowing By changing to NSK Molded-Oil mountedunit inserts, a drinks producer has overcome repeated problems of premature insert failures on the drive system of four sorting conveyors, improving their service life. At the beverage plant, cleaning processes comprising a mix of water and chemicals were destroying the bearing seals and washing out the grease pack on the company’s existing mounted units. As a result, the inserts within the mounted units had to be replaced every 5 to 6 months, and re-greased every 3 weeks.

accommodates any initial misalignment. In addition, the lubricant within MoldedOil inserts is durably incorporated inside a stable carrier medium, namely an oilimpregnated polyolefin resin. This type of lubricant cannot be washed away by liquids or steam, and prevents the ingress of contamination. Moreover, as the carrier only releases the lubricant

slowly, sufficient lubrication is maintained over a long operating period. Made from martensitic stainless steel, molded-oil inserts are ideally suited to applications which are in frequent and heavy contact with water. NSK South Africa Geraldene Govender Tel: (011) 458-3600

NSK concluded that a switch to molded-oil mounted-unit inserts would solve the issue. NSK mounted units comprise two basic components: the insert and the housing. Each unit consists of a sealed single-row ball bearing with spherical external diameter and extended inner ring mounted in a pillow block or flanged housing. The spherical fit One of the conveyor drives at the drinks plant, highlighting the harsh operating conditions for the mounted units

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