BULK
HANDLING Endorsed by: CMA l LEEASA l SAIMechE l SAIMH l
T O D A Y
March 2016
PREVENTING CRANE RUNWAY MALFUNCTIONS CHUTE DESIGN ESSENTIALS
Tailor-made and Tested
DRIVING TECHNOLOGY DELIVERING PRODUCTIVITY Sandvik Mining minimises your safety risks, operational interference and site construction time by pre-assembling shiploaders. This ensures that only a short installation and commissioning period is required to get a port operating again. Our shiploaders are designed to cater for a range of products loaded onto vessels ranging in size from Handymax to Panamax and incorporate a built-in dust collection system and dust-free loading chute.
For enquiries, please contact +27 (0) 11 657 4600 MINING.SANDVIK.COM
BULK
HANDLING March 2016
T O D A Y
Contents
On the cover: Tenova Takraf Tel: (011) 201-2300, www.tenova.com
SAIMH News 5 CMA News 8 Leeasa News Cover Story
African Mining Industry
Earthmoving
Endorsing Bodies
4
6
21 ‘Go’ or ‘No Go’
Beltcon
23 Chute Design Essentials 37
Tailor-made and Tested
10 New Ultramodern Yellow-metal Facility
Market Forum
•
CMA (Conveyor Manufacturers Association)
12 Still Feeling Bullish
•
Conveying
LEEASA (Lifting Equipment Engineering Association of South Africa)
•
SAIMechE (SA Institute of Mechanical Engineering)
•
SAIMH (SA Institute of Materials Handling)
•
also mailed to members of the RFA (Road Freight Association)
Trucking
13 A Fantastic Alternative 16 Improving Traction
Lifting
17 Preventing Crane Runway Malfunctions 19 Personnel and Material Hoists
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.promech.co.za
The monthly circulation is 3 673
Proprietor and Publisher: PROMECH PUBLISHING Tel: (011) 781-1401, Fax: (011) 781-1403 E-mail: bulkhandling@promech.co.za www.promech.co.za Managing Editor: Susan Custers Advertising Sales: Lin Patricio DTP: Lindy Fobian / Anne Rotteglia 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 2016
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The South African Institute of Materials Handling
Sample
The South African Institute of Materials Handling (SAIMH) is a Non-Profit organisation set up with an objective to encourage the transfer of knowledge associated within the fields of Bulk Materials Handling (conveyors, stacker, reclaimers, tipplers, train loading systems, etc.) through a combination of seminars and networking sessions. The SAIMH is made up of professional engineers, each practising their trade in a variety of organisations who volunteer their time to execute the SAIMH’s objective. The main aim is thus to promote the advancement of the art, science, theory and practice of the Bulk Materials Handling principles and techniques.
Company Affliates as at March 2016 Afripp Projects cc Brelko Conveyor Products (Pty) Ltd Bulkcon CPM Engineering CT Systems cc Conveyor Watch (Pty) Ltd David Brown Gear lndustries (Pty) Ltd ELB Engineering Services (Pty) Ltd Engicon Systems (Pty) Ltd Facet Engineering cc Flexco (SA) (Pty) Ltd
Hagglunds Drives SA (Pty) Ltd Hansen Transmissions SA (Pty) Ltd Hatch Goba (Pty) Ltd lllustech J & A Engineering Services Kimrae Engineering Prolects Loadtech Load Cells (Pty) Ltd MacsteelVRN Martin Engineering Melco Conveyor Equipment Morris Material Handling SA (Pty) Ltd
Osborn Engineered Products (Pty)Ltd PD Engineering Services cc PH Projects Holdings (Pty) Ltd Rio Carb (Pty) Ltd Sandvik Materials Handling Africa Screw Conveyors & Material Handling Senet SEW Eurodrive Spar Western Cape SSAB South Africa (Pty) Ltd Tenova Zest Electric Motors (Pty) Ltd
4 BULK Tel: (011)HANDLING 867-0902TODAY l Fax:March (011) 2016 867-0036 l Email: saimh@global.co.za l www.saimh.co.za
CONVEYOR MANUFACTURERS ASSOCIATION
From The Chairman’s Desk This month we are reminded that planning for Beltcon 19 has already commenced and authors and speakers are invited to submit a synopsis on topics relating to belt conveying. Beltcon 19 will be held over two days in early August 2017. The proud history of Beltcon conferences, held every two years, goes back uninterrupted to the first Beltcon held in 1981. The conference is regarded as a leading international forum for disseminating information to delegates on the latest technology. Case studies, particularly of South African installations, are always popular so if you know of a topic that could be of interest, why not ensure that a synopsis is submitted for consideration? A number of topics have already been identified by the Committee and invitations sent to the prospective speakers. Topics include the latest in research and design as well as case studies from many of the world-renowned names in academia and the industry.
Simon Curry
ets as low as possible. This is especially important in the current economic climate. Nevertheless, this unique opportunity for the South African audience to share information of this calibre cannot be missed. Synopses can be submitted to the IMHC on email to ctr@beltcon.org.za Simon Curry - Chairman
The conference is organised for the industry, by the industry, and every effort is made to keep costs of the delegate tick-
Membership at March 2016 All members subscribe to the CMA Code of Ethics ABB Industry Actom Afripp Projects Atlanta Manufacturing Bauer Bearings International Belt Brokers Belt Reco Belting Supply Services Bibby Turboflex BMG Bonfiglioli Power Transmissions Bosworth Brelko Conveyor Products Brevini Power Transmission SA (Pty) Ltd CedoTech cc Collisen Engineering Conveyor & Engineering Equipment Conveyor Watch CPM Engineering CT Systems David Brown Gear Industries DRA Projects SA (Pty) Ltd Dunlop Belting Products
Dymot Engineering Company ELB Engineering Services Facet Engineering Fenner Conveyor Belting (South Africa) Flexco SA (Pty) Ltd FLSmidth Roymec Hägglunds Drives South Africa Hansen Transmissions SA Hatch Goba Africa Hosch - Fördertechnik (SA) International Belting & Marketing Iptron Technology KevConBelt (Pty) Ltd Lesa Mining Equipment and Conveyor Belt Lorbrand M & J Engineering Martin Engineering Megaroller Melco Conveyor Equipment Moret Mining Nepean Conveyors NSK South Africa (Pty) Ltd OE Bearings Oriental Rubber Industries SA Osborn Engineered Products
Pegasus Industrial Services cc PH Projects Holdings Protea Conveyors Read Swatman & Voigt Regal Beloit South Africa Rema Tip Top South Africa Renold Crofts Rula Bulk Materials Handling Sandvik Materials Handling SA Schaeffler South Africa SENET SEW Eurodrive Shaft Engineering SKF South Africa Sprag Components cc Tenova Takraf ThyssenKrupp Industrial Solutions South Africa (Pty) Ltd Timken South Africa (Pty) Ltd Transmission Components Transvaal Rubber Company Veyance Technologies Africa Voith Turbo WorleyParsons RSA Zest Electric Motors
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March 2016
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COVER STORY
Tailor-made and Tested In competitive and challenging environments businesses need an advantage. With extensive engineering capabilities, an on-site laboratory and around the clock maintenance crews, Tenova Takraf Africa is making the best use of its strengths to improve the business of its customers. “Bulk Handling Today” chats to this key supplier of equipment and systems for bulk handling and open pit mining.
I
t’s been all systems go for Tenova Takraf Africa in 2016 with a move to their 3 400m2 head office in Spartan in February. The move brought the engineers to the lab and the administrators to the warehouse. The premises include 1 800m2 customer focused stores, 500 m2 laboratory space, and is home to over 120 years of engineering experience.
The laboratory is fully equipped with samplepreparation and mineralprocessing equipment
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looked at our strategy and how we could offer our customers better solutions. To do this really well, we needed to be in one location,” Richard notes.
Where we need to be
The move is showing positive results. “We’ve been in Spartan just over a month and already we are seeing more use of our lab.”
“Four months ago we took the decision to move all our operations into one location,” says Paul Davies, General Manager – Client Support Services.
The laboratory is fully equipped with samplepreparation and mineral-processing equipment and provides a convenient facility for liquid/solid separation test work, drop tests for the sizing of Bradford Breakers and other comminution test work. This saves on the expense of on-site test work and reduces turnaround time.
It’s a new location for some of the team who had spent a number of years at offices in Greenstone Hill.
“We had a great lab and warehouse in one location, and admin and engineering skills in another location. It didn’t make sense,” comments Richard Späth, General Manager - Engineered Technologies. “We
BULK HANDLING TODAY
March 2016
COVER STORY
Through a partnership with bulk solids flow company Greentechnical, the laboratory also provides material flow laboratory testwork to determine the flow of solid material through chutes, storage vessels, etc. “A testing environment enables us to meet customers’ requirement in terms of equipment sizing and process knowledge,” shares Richard. The lab is currently busy with liquid/ solid separation test work.
More with less
Great products are an easy sell when times are good, but when times are tough, you need a little extra. “Our customers need to be more productive with less,” adds Paul. “We have embarked on a development plan, and are modernising our equipment to be more cost effective,” says Richard. This is evident in Tenova Takraf Africa’s specialist en-masse conveyors where engineering skills are used to make conveyors more efficient and more suited to the customers’ needs. Tenova Takraf Africa also develops solutions for customers like junior miners. “These miners need tailored solutions, technically and financially. Equipment needs to be more mobile to suit the different locations in which they mine,” says Paul.
Close to the customer
Designing to a specific need is just one way Tenova Takraf Africa is meeting its customers’ needs; another is in their super quick response time. “When you deal with Tenova Takraf Africa you are dealing with someone in the country and if you need support or maintenance, or to see the engineer who designed the equipment you are using, we get in our cars and come to you,” Richard highlights. Paul adds, “Tenova Takraf Africa has a large stockholding in our warehouse ready for use, so we don’t need to import parts.” In addition to the Spartan office, Tenova Takraf Africa has satellite offices in Middleburg and Kathu, with expansion of the Western Cape office underway to better service customers in this area. Local knowledge gives Tenova Takraf Africa a headstart in South Africa where domestic procurement has grown in importance and necessity. “We can facilitate low cost procurement, and because we understand local supplier requirements and adhere to recommended processes, we are ready to supply state owned companies,” says Richard. As a wholly owned subsidiary of Tenova Mining & Minerals South Africa, Tenova Takraf Africa is
a Level 3 broad-based economic empowerment contributor.
Tweedraai expansion project
The capabilities of the team were put to the test on Sasol Mining’s Tweedraai expansion project on the Syferfontein mine near Secunda. Tenova Takraf Africa was responsible for the materials handling portion of the project that ran from 2013 to 2015. This was one of Sasol’s projects to ensure they have modern replacement operations to substitute some of their long-standing, but depleting, mines. The project included the use of optimised steel structures and designs utilising advanced technologies, which had been developed in-house by Tenova Takraf Africa, who designed and executed the project.
This was one of Sasol’s projects to ensure they have modern replacement operations to substitute some of their long-standing, but depleting, mines
The new conveyor system included the design and installation of three conveyors totaling 3 km, to convey coal at 4 800 t/h design capacity. Electrical and instrumentation systems, as well as bulk earthworks and civil foundations for the conveyor system and transfer towers, also formed part of the contract. Tenova Takraf is a key supplier of equipment and systems for open pit mining and materials handling, having provided hundreds of complete systems, as well as individual machines to clients all over the world in all climatic conditions. Globally sourced air pollution control, specialised handling equipment, and technology for the cement and fly ash industries ensure selection of optimal processing options. Tenova is a worldwide supplier of advanced technologies, products, and engineering services for the metals and mining & minerals industries. Tenova Takraf Africa, Richard Späth Tel: (011) 201-2300, Email: enquiries.TAFR@tenova.com, www.tenova.com
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ENDORSER OF “BULK HANDLING TODAY”
LIFTING EQUIPMENT ENGINEERING ASSOCIATION OF SA
LEEASA, formed in 2003, is a division of the Chamber of Engineering Technology (COET), a non-profit organisation. The association’s objectives include, but are not limited to: the transfer of knowledge and training within the field of the Lifting Industry, to improve safety, promote the use of standards and to promote Professional and Ethical practices.
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t is represented on the Engineering Council of South Africa (ECSA) and a number of ECSA committees as well as on various task teams at the South African Bureau of Standards (SABS).
What’s in it for you:
As an Individual member who is registered as a Lifting Machinery Inspector (LMI), you may qualify for any concessionary fee granted by ECSA (this could save you over R1 000 a year). ECSA registered COET / LEEASA members are awarded one Continuing Professional Development (CPD) credit in category
3 each year. CPD is an ECSA requirement to retain registration. Members obtain a discount on training and seminars validated by the association, especially useful in earning ECSA CPD credits. Members benefit from the collective power of a recognised and established association and collective co-ordination in dealing with authorities in policy making and matters concerning the industry. LEEASA has some 500 members (Individuals and Companies).
Tel/Fax: (011) 787-1302, Email: engineer@netactive.co.za, www.leeasa.mirrorz.com 8
BULK HANDLING TODAY
March 2016
BULK HANDLING TODAY
February 2012
1
LIFTING G
” UIDE
“
2016/17
“T
here is a real need in our industry for a one-stop reference guide that can be used by our members and users alike to navigate through the many safety and inspection requirements in manufacturing, selling, owning and operating lifting equipment,” says Ken Greenwood, Chairman of LEEASA (Lifting Engineering Equipment Association of SA).
“Having had a long history of putting together a bi-annual Lifting Guide, together with Promech Publishing, publishers of “Bulk Handling Today”, we intend the revised issue of the Guide (2016/2017) to be a comprehensive and a deKen Greenwood Chairman of LEEASA finitive publication, so much so that I would have no hesitation in recommending it as an authoritative self-standing training manual in our industry,” Ken adds. “This is an important mouthpiece for LEEASA as the only dedicated annual guide we endorse. It will be an accessible and clear guide on everything you need to know about lifting engineering equipment.”
The Guide will include: An in-depth explanation of the Regulations governing the lifting industry Clear information on which standards apply to the industry and how to interpret any grey areas Broad guidelines for manufacturers of lifting equipment and how to address safety concerns in this arena. Information on maintenance: inspection criteria, intervals and accompanying documentation Updated information on the various types of lifting equipment on the market.
LIFTING gUIDE 2014/15 Also publishers of “Bulk Handling Today”
If you would like your product or service to feature in this definitive Guide, Contact: Lin Patricio
Tel: 011 781 1401 / 083 637 7122 E-mail: bulkhandling@promech.co.za
New Ultramodern Yellow-metal Facility
EARTHMOVING
Babcock is the exclusive regional distributor for international brands and equipment including Volvo and SDLG construction equipment, Tadano mobile cranes and Winget concrete handling machinery. The company was also appointed the official distributor of Terex Trucks in October 2015 following the truck company’s acquisition by Volvo earlier last year.
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ith an extensive history in sales and servicing of construction equipment to the mining and construction sectors in South Africa, Babcock has had a presence in the Middelburg region for the last 16 years and has outgrown two previous premises in this period. The new Middelburg facility was purpose-built to assist and support customers in the region and is expected to service the coal mining fields of Middelburg and surrounds for at least the next 20 years. The estimated R100-million yellow-metal facility covers 30 000 square metres and features highly specialised and unique design elements as well as modern, high-end finishes. Babcock’s project manager Michael de Weijer, who was instrumental in managing the construction of the new facility, says that the ergonomic design was conceptualised around the flow of equipment, parts and people to ensure efficient operational and communication management.
Single level
Accordingly, the administrative open-plan offices are located across two floors. The workshop offices on the first floor overlook the 12 work bays and service facilities area comprising the component workshop, spray booths, wash bays and boiler workshops. All heavy equipment operation and parts are on a single level enhancing safety when handling these machines and heavy parts. The primary workshop covers an area of nearly
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2 000 square metres under roof and includes 12 nine-metre wide work bays in two adjoining rows of six bays, all serviced by overhead gantry cranes. All bays have a ceiling of 9 m under hook, making it possible to service mega trucks, such as the rigid and articulated dump trucks from Terex Trucks, bucket up. All the workshop bays, component workshop, spray booths, wash bays and boiler shop bays drain into a common settling tank and oil separation facility before being discharged into municipal waste. A further The warehouse has custom feature in the increased from 280 m 2 workshop is at the previous the railway premises to 1 615 m 2 tracks linkto accommodate an ing the wash increase in inventory bays to four and stock lines required workshop bays, specifically for tracked excavators and chain link front end loaders so that this equipment with high point loads does not damage the site hardstand.
Parts requirements
Parts requirements are served by the parts warehouse, connected by a three metre-wide east/west passage that runs along the entire length of the workshops and warehouse. The warehouse has increased from 280 m2 to 1 615 m2 to accommodate an increase in inventory and stock lines required.
EARTHMOVING
This increase is largely attributed to regional growth and parts for the new Terex Truck range. With extra stacking space of up to 5-6 m, larger volumes of each part number can be stored and there is also ample capacity for future expansion. The workshop offers easy access to counter sales for smaller parts, while on the other side, goods receiving and dispatch are serviced by a continuous loading ramp.
Overhead gantry
A component workshop of 198 m2, situated adjacent to the workshop and sharing a common tool store, is serviced by a 10 tonne overhead gantry equipped for engine, transmission and axle overhauls. The room is positively pressurised by an evaporative cooling system to reduce ambient temperatures while acting as a dust filtration system. The architectural design also incorporates energy efficient and modern design philosophies. The exterior overhang has a curved bullnose proportioned to prevent direct sunlight from entering the building in the summer months, while permitting winter sunlight into the first few metres of the ground floor, and assisting with natural interior warmth via convection up the glass façade in the cooler winter months.
Natural light
Floor-to-ceiling semi-transparent stacking doors serve as workshop doors instead of the standard industrial roller shutter doors, to take advantage of natural light and to facilitate heating in winter, as well as bringing organic elements into the work space for a more efficient and productive work environment. Other intelligent design features include motionsensor lighting in bathroom cubicles, foot-operated
faucets for ease of access for staff that handle oil, water tanks with a reserve of five days’ water in the event of a water supply cut, and a 500 kVA generator to allow work to continue during power outages. “From this new flagship branch we can deliver improved service to our customers in the Middelburg region and achieve a faster turnaround time,” says Babcock’s Sales Director for Equipment, David Vaughan.
Collaboration
“Customers are always looking for the most costeffective way to move material,” continues Vaughan. “When we increased our product line to include the Terex Truck range with a payload of up to 100 tonnes, we knew we had the facilities to bring these trucks to our customers. In fact, at 9 metres wide, the workshop bays were purposeThe facility has been built for trucks designed with ample with payloads of up to 150 tonnes. turning space for Furthermore, the these mega trucks facility has been designed with ample turning space for these mega trucks.” Babcock’s equipment business currently has 25 branches and four independent dealers in southern Africa and operates in various market sectors, the largest of these being the mining and construction industries.
Babcock David Vaughan, Email: david.vaughan@babcock.co.za
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TRUCKING
Still Feeling Bullish “The industry has been through declines in 2001 and 2009 and the strategies we applied then are no different from what we require today to keep our business on track and even to grow. Success comes with being able to analyse the problems and institute growth and development strategies without pressing the proverbial panic button,” says Isuzu Trucker CEO, Craig Uren.
“
Craig Uren
The perspective of the rest of the world is that the demand for trucks has not been severely impacted as they have faced similar pitfalls such as fuel prices, political upheavals and immigration crises. The drought and our internal politics with load shedding, bad administration and labour unrest make our situation unique compared with the rest of the world.” However, the year 2015 can be considered as the best ever in the short history of Isuzu Truck South Africa, for not only was it the most challenging but also the most rewarding as the results anticipated for the ten-year plan were achieved one year earlier than expected. The 4 550 units sold in 2015 and corresponding 14.9% overall market share ensured that Isuzu Trucks ended as the number one supplier for the third year in a row. In all, the full spectrum of the product range contributed to the overall results, each having increased their market share, the NSeries from 23% to 27% and the F-Series from 29% to 33%.
Most rewarding as the results anticipated for the tenyear plan were achieved one year earlier than expected Growth stage
“We have now positioned the brand where we want it to be and have strategies in place to maintain that level as we are still in a growth stage of that strategy. The results we achieved in 2015 are definitely not the end point but merely part of the journey. I cannot foresee any major hurdles to hinder our progress, except perhaps some major global or local events. The market will, however, dictate where the level will be, if any,” says Craig Uren. The acquisition of Kanu and ACT in the Eastern Cape was a bold move for ITSA and the results in the four months since the acquisition endorsed the economic value of the move, which enabled the company to meet and exceed its targets for the year. The production at Kanu/ACT is not totally devoted to Isuzu Truck as it also supplies the general market where necessary. “Kanu/ACT is doing well and so far is filled to capacity. This acquisition has enabled us to get the solution to the market in the most effective manner possible. As we grow in volume, Kanu/ACT
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grows with us. This has meant great savings for the dealer, who receives a complete vehicle from the factory and eliminates the need to move the vehicle around for the fitting of the various accessories, thereby eliminating unnecessary expenses and shortening the turnaround time once the sale has been concluded.
Good customer base
“For Isuzu, Africa is a huge market opportunity. Around the world Isuzu does well, but Africa needs a lot more work to entrench the product. We have established a good customer base in neighbouring territories and in 2015 we exported more vehicles there than we had done in the last five years. Generally, Isuzu Trucks footprint in Africa is expanding, especially at the assembly facilities in Egypt, Kenya and South Africa. Isuzu Motors Limited Japan sold more than 20 000 new trucks into Africa last year and it is anticipated that this number will grow considerably in the next five years,” says Craig. The increase in market share and the expansion of the variants in the Isuzu Trucks range have brought a new dimension to the support structure for the product. The parts and service backup has been simplified with the introduction of common components that fit the range of vehicles. There are only four engine derivatives and four transmission models used in the entire range. Also, common components have been incorporated in the cab design, simplifying the replacement of body parts. “Looking ahead, we have not changed the game plan but require mastering the plan to build on the base that has been set to support the client, from body building, parts and service, and warranties. Our results are there but we require extending the journey further. Extending the journey for our customers means also extending the economic life of their vehicles. For this purpose we have a component replacement exchange programme in place called “Isuzu Drivetrain” for dealers to utilise. “The product range will not undergo any major changes, except for some minor cosmetic adjustments, so the emphasis will be on extending the value of the brand ‘For the Long Run’,” concludes Craig. Isuzu Truck South Africa, Craig Uren, www.isuzutrucks.co.za
CONVEYING
A Fantastic Alternative Ten years after first being introduced at a gold mine in Welkom, the Deebar Rail-Veyor is proving its worth. This unique system that is fast gaining traction for its features and benefits, is undergoing a complete revamp. “Bulk Handling Today” finds out more.
T
he 5.1km underground system operating in Phakisa shaft at the Harmony gold mine has completed more than 925 000km moving over 5,4 million tons of material since its inception in 2005. This is roughly equivalent to moving the pyramid of Giza. It was time to upgrade, says Richard Barley, marketing manager of Deebar Rail-Veyor. “The system continues to work extremely well and is very costeffective, however, there are some changes required
to stabilise and optimise the system for the years to come,” he explains. Additional brake stations are being added, together with technology and components that have changed over the last 10 years, such as the SCADA system (which includes the reporting facility). In addition, an upgrade in the software will allow for greater control. Deebar Rail-Veyor, together with Adroit and Mitsubishi (MAPS), have partnered up to provide the latest in technology to the system.
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CONVEYING
In 2004, Deebar Rail-Veyor acquired the concept and reengineered the system, due to the necessary technology being available and was successful in manufacturing the first commercially-built system in the world. Having put the various design applications, copyrights and international patents in place, the system was put into operation a year later at the Phakisa shaft. “A test system was first built on the surface. After testing and with its effectiveness proved, it was moved underground where it continues to operate to this day. It has the capacity to move 70 000 tons of ore per month.”
Out with the old
Remotely operated
The upgrade commenced in December 2015 and is expected to be completed by the middle of this year. The upgrade will be performed during maintenance periods and the only downtime, will be for the final commissioning. “The system is fully automated and is operating completely underground and controlled from a central control room underground, however it can be remotely operated from the surface,” adds Richard. “It only requires a single operator and is extremely efficient moving ore from the Phakisa Shaft to Nyala Shaft where existing hoists are utilised to transport the ore to surface.” While the system has been operational at Harmony for ten years it is still in its infancy stages compared with other conventional bulk material transport systems, however the product is rapidly gaining momentum.
It combines the best features of both the standard conveyor belt and rail systems for transporting material that is moved with high flexibility at an increased capacity while being able to negotiate curves like a rail system Close but no cigar
A very similar system was first conceptualised in the late Sixties by the French state railroad, Seccam, but it never really got off the ground, as the necessary technology such as variable speed drives and fibre-optic communications was just not available to make it effectively controllable and cost effective at the time. The idea then re-surfaced in the USA, when a demo model was built to test the handling capabilities.
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It’s not an exceptionally complex system, Richard tells us. “It’s probably best described as a roller coaster mixed with a conveyor. It combines the best features of both the standard conveyor belt and rail systems for transporting material that is moved with high flexibility at an increased capacity while being able to negotiate curves like a rail system.” It consists of a light rail track with a number of twowheeled cars that are inter connected to represent a long open trough moving along a track. Each car is connected to the front car by means of a speciallydesigned clevis that allows articulated movement to negotiate curves, bends and tipping. Sealing of the gap between the cars is maintained by using overlapping flexible rubber flaps which prevent spillage of the material and operate as a discharge chute for tipping the load after being transported. There is no locomotive or integral drive unit on the train. Instead, a number of strategically-placed energy efficient drive stations with foam-filled tyres in contact with the side drive plates of the cars provide the driving force. “The rail track does not have to support a locomotive’s weight as in the case of a conventional railroad system,” explains Richard. The result is an energy efficient, cost-effective bulk material transport system that has been found to be very competitive in the medium range delivery category especially between 1km and 50km. “The system really has gone from strength to strength as ongoing development has taken place.”
Meet the mine’s needs
A second system has since been introduced at a mine in the North West. “It’s been operational for a number of years and operates slightly differently from the first,” Richard explains. In this case, platinum ore from a stockpile has to be moved to a nearby processing plant 2.2km away.
CONVEYING
The mine was operating trucks at the time which was proving very costly and a conveyor belt couldn’t support the 30-degree bend without installing a transfer point, whereas the Rail-Veyor met all the criteria set by the mine. Here, a complete surface operation has been designed specifically to meet the needs of the mine. “It is exceptionally cost effective and energy efficient with operating costs only averaging R2.21 per ton.” When operating at full production, it will transport around 525 000 tons of platinum ore every month. There are several benefits to using their technology, Richard asserts. “There is no denying that when moving material within 1km and 50km, our system is the most effective as proven by the Coaltech Transport Investigation done by Crickmay & Associates (Pty) Ltd. Operating costs are less than a heavy rail system on a cost per ton basis.”
It is exceptionally cost effective and energy efficient with operating costs only averaging R2.21 per ton
Much more flexibility
ABSOLUTE MATERIAL FLOW CONTROL
According to Richard enquiries about the system have increased exponentially in the past few years as the cost and energy saving benefits especially become very attractive. “We have also embarked on a strategy to introduce the system into Southern Africa. Countries that we want to target include Zambia, Botswana and Namibia. “Due to its simple design and low operating costs, which are based on energy used per ton/km, ours is an extremely cost effective system, Richard concludes. “It offers a very good alternative to the conventional methods of moving bulk material.” Deebar Rail-Veyor Richard Barley Tel: (011) 873-4332 Email: info@rail-veyor.co.za www.rail-veyor.co.za
Coralynne & Associates +27 (011) 849 3142
It is also far more flexible than conventional conveyors. The system can be installed to take a direct route or it can negotiate bends, be installed in rough terrain, under bridges, over roads and return in a 30M radius and climb up to 11 degree inclines. At the same time, the system has far less downtime than when using traditional bulk handling solutions due to its reliability factors and it can be fully installed within eight months, depending on the application.
ABSOLUTE MATERIAL FLOW CONTROL
• Optimum material flow • Up to 80% decrease in material degradation • Reduced dust and noise levels • Virtually maintenance free • Greatly reduced spillage • Significant reduction in belt damage
TM
SOUTH AFRICA
Phone: +27 (0) 11 827 9372 Email: info@webachutes.com
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CONVEYING
Improving Traction Conveyor belt slippage, poor traction, inferior wear properties and inadequate water shedding are nightmares which plague plant operators on mines. All of these can cause unplanned downtime with associated cost implications. However, more critically, conveyor belt slippage is potentially dangerous and could even result in catastrophic failure on a plant. In instances where slippage continues, there is an increased danger of fire as well as damage to the carcass and splice, caused when the belt does not grip.
T
his is according to Mark Jarrett, national sales manager of Multotec Wear Linings, who says that the company’s MultoLag pulley lagging functions as a maintenancefree wear resistant cover that is applied to pulley shells to improve traction in the case of drive pulleys and provide a polished low friction surface on non-drive pulleys.
non-drive pulleys provides minimal friction, less resistance and therefore no wear. Conversely, the studded tiles on the drive pulleys have a high coefficient of friction of 0.78, which means no relative movement between the surface of the ceramic-lined drive pulley and the surface of the conveyor belt. What is significant is that without relative movement between surfaces, there can be no wear.
Cost-effective
Maximum traction
MultoLag has become a widely-accepted solution for mining and industrial operations as a cost effective response to these recurring problems. “This lagging is particularly effective in aggressive conditions, even on bucket elevators or where material is inevitably trapped between the pulley shell and the conveyor belt. It is suitable for wet conditions and other applications where a low coefficient of friction or a high level of traction is required on drive pulleys or where general wear protection of the non-drive pulley is needed,” Mark says.
Mark points out that traditional rubber or epoxy pulley lagging has a much shorter lifespan than that of ceramics He points out that traditional rubber or epoxy pulley lagging has a much shorter lifespan than that of ceramics. “This can be attributed to the fact that material is removed from both the rubber lagging and the rubber belt bottom cover when belt slippage occurs. In turn, direct bonded ceramic lagging results in a significant extension of the useful pulley life.” The system uses standard smooth high alumina ceramic tiles for non-drive pulleys and studded tile lagging for drive pulleys. The smooth/polished surface provided by the very hard ceramics on the
safrench
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Ceramic lined drive pulleys are covered with high density 20mm x 20mm x 6mm ceramic tiles, with 1mm high round-edged studs on the tile face that create maximum traction, without the associated damage to belts. The 6mm thick high density smooth ceramic tiles are bonded directly to the pulley’s surface with specially-formulated Multotec Hi-Bond epoxy. “This epoxy allows us to achieve a bond strength at least 70% higher than that of rubber to steel or rubber to ceramic. It also allows for surface flexing, corrosion protection and water dissipation. In the unlikely event that patching is required, local damage can be repaired quickly without removing the surrounding pulley lining,” Mark says. “The reduced maintenance and downtime, together with enhanced safety benefits, have made the MultoLag a highly popular choice for leading mining and minerals processing companies at coal terminals, beneficiation plants, cement plants and quarries. For instance, in one particular application, the system has been in operation for over five years in comparison to a mere eight months for the original liner,” Mark concludes. Multotec Group, Bernadette Wilson, Tel: (011) 923-6193, www.multotec.com
LIFTING
Terex Material Handling product manager Richard Roughley
Preventing Crane Runway Malfunctions Daily loading and handling of heavy objects such as containers, paper and other material eventually take a toll on crane runway systems, which require continued inspection to ensure that unscheduled downtime, fatal incidents and damage is avoided.
R
unways are used for cranes, storage and retrieval machines, to ensure quick and easy transportation of goods and material from one point to another. The condition of a crane runway and the crane geometry have a decisive influence on the service life of numerous crane components.
The three-dimensional surveys are carried out by trained personnel to help customers eliminate production downtime “Smooth travel motions can only be ensured by a perfectly aligned crane runway and crane geometry, which prevents premature wear of the travel wheels and abrupt changes in the travel speed, as well as unexpected load sway,” explains Terex Material Handling and Port Solutions (MHPS) product manager, Richard Roughley. Terex MHPS conducts thorough runway surveys to ensure that machines and equipment are able
to perform at uninterrupted optimum levels. The three-dimensional surveys are carried out by trained personnel to help customers eliminate production downtime, cost-intensive repairs and breakdowns, by detecting structural damage when it occurs and implementing counter-measures.
High precision measuring
Richard emphasises the importance of a well maintained runway. “The travel characteristics and the availability of an installation are impaired when specified tolerances are exceeded. Terex MHPS surveys are conducted using an internationallypatented laser measuring system (LMS) for high precision. The survey is cost-effective, safe and can be carried out quickly and easily, without implementing blocked zones, protective barriers or temporary clearance of production.” The LMS survey is carried out in a vibration, turbulence and interruption-free environment. Equipment used in the LMS surveys include; automatic alignment lasers, a self-propelled trolley, laser distance meter with positive centring arrangement BULK HANDLING TODAY
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The survey results are immediately available on the laptop and come with reports in graphical and table form for easy interpretation for rails, a laptop with a radio modem, and control and evaluation software. The laser sends out a horizontal visible laser beam, while the remote-controlled rail test car is directed to the measuring points.
Evaluation
At each measuring point, the horizontal and vertical deviation and the rail gradient are measured regularly. Terex MHPS evaluates the quality of the crane runway and geometry, parallelism of travel wheels and guide rollers for deformation. The evaluation and survey of storage and retrieval machines, as well as ground rails and high-bay racking, are included if requested. Once the survey is done, the results are checked immediately on a laptop, before measurement data is printed. “The survey results are immediately available on the laptop and come with reports in graphical and table form for easy interpretation. The report includes possible repair requirements and cost-effective correction proposals to eliminate any defects found,� Richard concludes. As of July 2015, Demag Cranes and Components and Terex Port Solutions merged to form Terex MHPS, as part of a global integration and business legal entity simplification process within its parent company, the Terex Group. The restructuring and rebranding has resulted in a company that offers complete intermodal handling solutions that fully-encompass ship, road and rail transport. Terex MHPS, Richard Roughley, Tel: (011) 897-8123 Email: richard.roughly@terex.com
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LIFTING
Personnel and Material Hoists One of the primary challenges on any construction site is the need to move both people and materials to levels where critical activities need to be performed, and to do this in such a manner so as to maximise productivity while ensuring optimum safety.
M
itsubishi Hitachi Power Systems Africa (MHPS) found the ideal solution in Orbit personnel and material hoists which will enable the contractor to provide safe, effective and efficient services at its contract at Kusile Power Station. The Orbit hoists will be installed at two of the boiler sites on the project.
Moving such components manually was not an option as construction tasks can be unnecessarily delayed
This is according to Awie Esterhuizen, scaffolding discipline manager at MHPS, who explains that while heavy loads are moved using tower cranes, this mode of materials handling cannot be justified for smaller components such as scaffolding material. Moving such components manually was not an option as construction tasks can be unnecessarily delayed and moving people without the required materials would have resulted in avoidable standing time and a loss of productivity.
Challenge
“Our challenge was to find equipment which would transport both men and materials to various levels of the 110 metre tall construction, thereby reducing manual handling of equipment and subsequent risk of injury while improving productivity. And we needed to be able to do this at a speed that would be both safe and effective,” Awie explains. He says that the vertical lifting of men and materials to levels on such a high construction is not often appreciated in terms of its complexity. “In a nutshell, the challenge is to effect this movement onto a construction that is in the process of being constructed, in order to fully construct it.” Torre Lifting Solutions was able to respond to this need and provide a turnkey best fit solution using the Orbit personnel and material hoist. The scope of supply included procurement, transport, import, installation and commission of the hoists. Awie says that by Torre Lifting Solutions assuming the role of a business partner rather than a single focus supplier, MHPS was able to focus on the work at hand. This purpose engineered single mast hoist has two separate cages; one with a 2t capacity to carry people and the other capable of carrying 2.3t of materials. Both cages operate simultaneously and most importantly the configuration of the hoist allows for materials to be loaded by forklift, speeding up the operation. The design of most material hoists does not facilitate this type of mechanical materials handling which means that some 5 000 pieces of material need to be manually moved to the hoist for up and off-loading.
Critical
“Our equipment is able to accept material mechanically and, being able to load 5 000 pieces per lift with a round-trip cycle time of 15 minutes, we can move all the material required per day within two to three hours. This feature is critical to productivity on site,” Awie adds.
BULK HANDLING TODAY
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LIFTING
The configuration of the hoist allows for materials to be loaded by forklift speeding up the operation
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The Orbit material hoist operates at a speed of 22 metres per minute while the personnel cage travels at 96 minutes per minute.
Awie says that while a technical support service is being provided by Torre Lifting Solutions to ensure continuous availability, MHPS’s pre-procurement research indicated that this specific model is both reliable and robust under a range of operating conditions.
Orbit equipment is engineered with all the requisite safety features including integral lock-out mechanisms to prevent accidental operation or personal injury.
Torre Lifting Solutions, Quentin van Breda Tel: (011) 822-8782 Email: quentin@safrench.co.za www.safrench.co.za
BULK HANDLING TODAY
March 2016
AFRICAN MINING INDUSTRY
‘Go’ or ‘No Go’ While the continent’s abundance of commodities is already helping meet global demand, Africa is set to see a growth in secondary industries related to mining. This is likely to result in exponential growth in the industry.
C
Gerrit Lok
onsulting engineering company SMEC has an extensive presence in Africa, with 1 000 employees in South Africa and a further 450 in the rest of Africa. Its involvement extends mainly to NPI (Non Process Infrastructure) projects, including power, water, roads, bridges, urban development and geotechnical work. “Our clients are typically governments or global institutions such as the World Bank. We focus on engineering and engineering supervision, feeding into most operating models, from EPCM (engineering, procurement and construction management) to EPC (engineering, procurement and construction,” Gerrit Lok, general manager, resources: Africa at SMEC, says.
Many companies see the lack of infrastructure as a huge stumbling block, but given our core skill sets, we look at this as an untapped market A differentiator for SMEC in the marketplace is that, interestingly, it subscribes to both models. “If projects are not well defined and/or maybe subject to significant change, then we would prefer EPCM. However, for well-defined projects with a limited chance of significant change, EPC tends to be preferred.
Mixed project model
“From a risk perspective, EPC tends to be preferred by financiers. Current research on project surveys tends to show that a mixed project model yields optimal results. Fundamentally, if practised correctly, EPCM should, however, deliver a lower capital cost, with all things being equal.” Political stability, safety and health, and security risks are common themes that “we continuously monitor internally and externally. Business risk challenges such as payment risks are also important, but this seems to be less of an issue due to our operating model and strong focus on having an established footprint in the countries we operate. “Many companies see the lack of infrastructure as a huge stumbling block, but given our core skill sets, we look at this as an untapped market. The drawn-out processes in funding the larger strategic projects in African countries can be a challenge, and often results in lost opportunities,” Gerrit cautions.
Dearth of Greenfield projects
The downturn in the global commodities market has resulted in a dearth of Greenfield projects in Africa. “Focusing on the mining and oil and gas industries, I think the single largest factor impacting ‘go’ or ‘no go’ decisions are really the unpredictability of global commodity demand forecasts.” Gerrit explains that the volatility in estimates over often short periods of time, coupled with questionable information on economic activity, especially from China, makes it very difficult for companies to BULK HANDLING TODAY
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AFRICAN MINING INDUSTRY
Bulk Materials Handling Mining | Process Plants | Pit to Port
At the forefront of materials handling systems
make long-term commitments. “Secondly, there is a marked surplus in production capacity for most commodities, given the short- to medium-term demand forecasts.” This trend is reflected in the marked drop in exploration budgets, which have declined anywhere from 13% to 50% from 2013 onwards. “It has, however, not dried up, and exploration programmes have become more focused,” Gerrit argues. “There also seems to be a preference for exploration in gold, copper, PGMs and nickel.”
African ‘hot spots’ for mining
This is because Africa is blessed with an abundance in this regard. “However, I like Tanzania, Ghana, Kenia, Uganda, Guinea, and the Democratic Republic of the Congo. Exploration is only in its infancy in these countries, as far as I am concerned.” Gerrit points out that the normal SADAC (Southern African Development Community) countries will always remain a part of this mix.
WorleyParsons supports the mining and minerals sectors, offering a scope of engineering and draughting capabilities in conveyors, stockpiles, chutes, hoppers and silo design using the latest software analysis tools. We have expertise in understanding material flow in design and implementation of materials handling systems. - 1,200 local employees - Deep local knowledge - Global expertise - BBBEE Level 2
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countries
148
offices
31,400
wprsainfo@worleyparsons.com www.worleyparsons.com
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WP MH ad 90x267.indd 1
people
Volatility in estimates over often short periods of time, coupled with questionable information on economic activity, especially from China, makes it very difficult for companies to make longterm commitments “South Africa has been, and will remain, core to our business. It has been a great base from which to expand into Africa. South Africa is not immune to the global economy and is experiencing many similar challenges as elsewhere in Africa and the rest of the world.” Important factors in attracting more foreign investment and the attention of global mining players is to provide a competitive, secure business environment where predictable business outcomes can translate into long-term sustainable growth. “I would say the important things are to do your homework, be committed for the long term, manage your risks diligently and make a positive contribution to the environment that you are going to operate in,” Gerrit concludes. SMEC, Gerrit Lok, Tel: (011) 369-0600 Email: johannesburg@smec.com
March 2016 2015/11/19 12:50 PM
BELTCON
Chute Design Essentials This article attempts to give the reader some simple rules to apply to chute design. Any discussion on chute design would normally require at least a week of deliberations, definitions, mathematics and particle theory. There are numerous papers available, many of which were presented at previous Beltcon conferences.
H
owever, further information and clarification is quite valid considering that the transfer of material from one belt conveyor to another is one of the most crucial design characteristics, and yet still remains one of the aspects least considered in the initial design of a system. In most instances the transfer of material between belts is the defining parameter in the selection of a suitable belt profile. It is therefore worthwhile to define and discuss some of the important parameters in chute design. Simple formulae and rules are presented that are useful in the design of efficient transfer points. Despite the many packages that allow for the simulation of the flow by computerised methods, it is of importance to be familiar with the basic formulae from which these simulations are derived in order to understand the more complex processes, many of which have been presented at Beltcon conferences in recent years. The basic formulae, to which younger engineers may not have been exposed, remain important particularly in instances where the extensive computing power required by chute design packages is not available.
Definition of a chute
A chute is defined in the Oxford dictionary as “A sloping channel or slide for conveying things to a lower level”. This is a perfect definition of both a curved chute, where the chute body acts as the slide or of the sloping portion of the material in a Rock-Box type chute where the material is the slide.
The problems (challenges) with chutes
The following list is drawn from a paper presented at the Chute Design Conference organised by the Bionic Institute in 1992. The problems as well as the solutions thereto remain essentially the same even with the passage of time. What has happened is that computer ability has increased, which allows for a quicker resolution to the problems (provided that this is correctly applied). • • • • •
Spillage Load zone turbulence Load centring Poor skirt board seal Impact idler maintenance
Adriano Frittella, AFripp Projects
• • • • • • • • • • • • • • • • • • • •
Abri Smit, ELB Engineering Services
Inadequate skirt board length Dust control Material degradation Belt tracking Poor provision for clean up Chute wear Inadequate provision for belt cleaning equipment Inadequate inspection access Belt damage from large lumps Belt wear and abuse Material build up – plugging Noise Structural support of chute and skirts Lack of attention to detail design Loading onto transition area Corrosion Unknown material characteristics Economic considerations Safety issues Housekeeping
While many of the above are maintenance related issues there are many that can be grouped under one banner: lack of attention to detail design.
The critical factors
There are some critical factors which are paramount in chute design. These are: • Reduction of impact on the chute faces • Reduction of impact on downstream belt • Centralised loading onto the downstream belt. A more complete set of design criteria that characterises an efficient chute is one that: • Is not prone to blockages • Allows for the transfer of material with minimal wear to the chute surfaces • Allows for the transfer of material with minimal wear to the downstream belt • Results in minimum material degradation • Results in minimum dust production • Centralises the load onto the downstream belt, hence minimising belt wander BULK HANDLING TODAY
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chute, or, in the event that a Rock Box is selected, design the Rock Box so as to collect and transfer material in an appropriate channel. • Design the Spoon (discharge distributor) and define conditions for minimum wear in the chute and on the downstream belt. The process is iterative and may be affected by factors such as limitations on head room, variations in lump size or in fact, the type of material. While often the designer is forced to compromise on certain design criteria (eg chute and belt wear and material degradation) the requirement to prevent blockages and reduce the possibility of spillage must never be compromised.
Indicators for designing efficient chutes
The following methodology has been recommended by one of our most eminent South African conveyor designers, Graham Shortt, for the design of conveyor chutes.
Figure 1. How NOT TO design a chute
Chute Hoods
The chute hood should be dimensioned to cater for the following:
Figure 2. Position of inspection hatches
• Results in minimum material segregation. In order to achieve the above objectives, the designer should follow a logical design sequence as follows: • Know and understand the properties of the material to be conveyed • Know and understand the nature and characteristics of the application • Plot the trajectory of the material • Design the Hood (discharge collector) and define conditions for minimum wear in the PURPOSE
HEIGHT (min)
WIDTH (min)
Observation
300
250
Servicing belt cleaners, sprays, etc.
300
350
Liner replacement
450
600
Maintenance personnel access
650
650
Table 1. Inspection and access openings in chutes
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• The side plates should clear the pulley face by a minimum of 50mm. This distance is measured from the inside of any liner plates which may be attached to the chute hood. • The hood height at the material entrance should be at least 0.5W, where W refers to the belt width. The height should allow sufficient space for the material burden to pass unhindered, including the possible incidence of larger rocks located on top of the normal burden. In this case, the minimum hood height should be in excess of 3×bL, where bL is the maximum lump size. • The hood flanks and cover should extend backwards at least 850mm from any nip point. • The hood may be provided with inspection or access openings, as required, located out of the material stream. The inspection openings should be easily and safely accessible. The inspection openings should be covered. For chutes that are de-dusted, the inspection and access openings should be designed to allow the minimum ingress of false air. The opening size must be sufficient for its purpose. • Where de-dusting is required, the hood should be provided with a back screen or apron seal, to limit the ingress of false air. The apron seal may be made of 3mm (minimum) reinforced rubber cloth, attached to the chute hood entrance. The apron seal should be vertically slit to allow the material to pass. The slits are normally spaced
BELTCON
at typically between 100mm and 150mm. • The hood is placed over the head or discharge pulley, which is located with respect to the equipment being fed. The location of the pulley is determined by consideration of the material trajectory over the pulley and the nature of the equipment being fed. The material trajectory is determined by the application of standard calculations. For conveyors discharging into hoppers and bins, the conveyor discharge pulley can be located to either feed the bin centrally when the bin is empty, or to allow central feed when it is full, as specified by the engineer. For cases where, for structural reasons, the bin must always be centrally loaded, the conveyor hood must be equipped with an adjustable impact plate or curved trajectory plate, in order to deflect the material stream into the desired path.
belts of relatively high speed (belt speeds in excess of about 2.0m/s) that carry washed and sized material of lump size greater than 30mm. Where drop boxes are specified, they should be designed to be self-draining. The base plate of the drop box must therefore be inclined at least at 10° to the horizontal plane. The drop box is then equipped with a replaceable lip liner, located to allow the passage of water underneath it.
Chute Body
• The chute body should be designed to suit the transfer requirements, without changing the direction of the material severely. The area of the chute containing the body of the material flow must be at least 2.5 to 3.0 times the area of the material, based on the design capacity of the conveyor and the material speed at the point of consideration. The minimum area of the chute is then given by
(1)
Where S = Material stream speed (m/s), (which could be belt speed)
D = Bulk density of the material (t/m3)
And Cdc = Belt design capacity (t/h)
Figure 3. Typical Dead Box design
• The chute should be designed to minimise the impact height from one conveyor onto another, as far as the plant layout allows. The chute should be designed to minimise impact of the material on the sides of skirts on the conveyor being fed. The rear impact point of the material onto the conveyor is normally located 150mm upstream of the first impact idler. Loading the conveyor in the transition zone from flat to trough is to be avoided as far as possible and should only be seen as a last resort.
• The chute body should be designed to centralise the material onto the downstream equipment. Material flow that tends to misalign the downstream belt is to be avoided. To this end, the use of ‘Vee’ bottom chutes is often encouraged, especially for in-line transfers from one conveyor onto another. For right-angled and skewed transfers, the use of adjustable impact plates or curved trajectory plates is recommended to change the direction of the material flow. The trajectory of the material will always impart some misalignment on a right-angle transfer. For this reason, the use of deflector plates is recommended. For material that is wet or prone to plugging, the impact plate ought to be designed to be self-cleaning, which may involve some test work. • The use of drop boxes is discouraged for material having a high content of fines or moisture or both. Drop boxes are also not always acceptable on conveyors handling diamondiferous material. Drop boxes may be designed for
Figure 4. The use of multiple Dead Boxes to reduce impact
• Where the chute sides slope, the valley angle must not be less than the minimum slope angle for the material and liner combination. BULK HANDLING TODAY
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The valley angle is determined from the wellknown equation as
(2)
Where the angles A and B (the slopes of adjoining plates) are measured from the horizontal, and angle C is the valley angle, also measured from the horizontal.
off or isolating mechanism, such as a clam-shell gate, or radial gate, in order to prevent flooding of the receiving conveyor under trip-out conditions, when the conveyor coasting time is less than the loaded screen run-down time. The gates may be programmed to automatically close rapidly (in less time than the conveyor coasting time), and to open smoothly and slowly, in order to deliver the screen run-off to the conveyor in a reasonably controlled manner when the system is restarted. • For chutes exiting hoppers, bins, silos and stockpiles, the chute design must accommodate the requirements of the feeding device, such as the vibrating, belt, apron or other type of feeder.
Figure 5. Valley angle
• The geometry of the chutes under silos and bins, feeding onto belt or apron feeders, are normally determined in conjunction with the material flow engineer.
Chute Exit (Spoon)
• The chute exit should be dimensioned to allow the unhindered passage of the material. The exit opening minimum dimension should be at least 2.5 times the maximum lump size of the material, and must have an area at least 2.5 times the area of the material, based on the design capacity of the conveyor and the belt speed, as indicated earlier. Where the chute feeds into skirts, the chute width must not be greater than the width of the skirts. Any necking or reduction in width of the chute body must comply with the chute wall slope and valley angle requirements. • The chute exit should be designed to impart to the material some velocity in the direction of flow, where the feed is onto another conveyor, wherever possible. A common specification is for the exit velocity to be within 10% of the receiving belt speed. • For chutes exiting at right angles from screens onto conveyors, the chute should cover the full width of the screen discharge and ought to be equipped with adjustable, replaceable deflector plates, placed at approximately 70° to the horizontal, located above the conveyor belt surface. The deflector plates must be dimensioned to allow the full passage of material, without creating a cut-off area over the conveyor belt. Chute exiting screens may be provided with a cut-
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Figure 6. Typical chute outlet requirements
Chute Liners Chute Hood - Under normal conditions, the chute hood side plates are not lined. If the material trajectory is such that the hood front plate or side plates will experience impact, then only the areas subject to impact should be lined, in order to minimise the mass (and cost) of the liners. Chute Body - Only the areas where the material impacts or slides should be lined. Chute Exit and Skirts - The exit of the chute is normally lined wherever the material impacts or slides. Skirts should be lined full length. The depth of liners should be at least equal to the depth of material contacting the skirts. In the impact and acceleration zones, the skirts should be lined full depth. Types of Liners - The following types of liners may be considered for selection: • Mild Steel (Grade 300W). This may be used on material that is sized and washed. The liners may be used in areas of sliding contact or light impact only. • VRN-500. This is preferred at locations where impact is high, or where the material lump size is greater than 100mm – 150mm. • Ti-Hard, Rio-Carb or other harder grades of liner steel have high wearing properties and should be considered, based on the specific application. • Solidur or equivalent UHMWPE. This may be specified in locations where the material is sliding. These liners should not be specified in areas of high impact, or material with large lumps and sharp edges. This material is especially useful for lining the back plates of
BELTCON
chutes and for lining dribble chutes, in order to improve material flow. • Ceramics. This is useful where the action of the material is largely sliding and there is a significant moisture content in the material. These liners should not be specified in areas of high impact, or where the material lump size is greater than 100mm to 150mm. Ceramics are best utilised where the body of the chute has a long sliding portion and where water is introduced to wash down fines collection areas. • Rubber. These liners are best utilised in primary crushed material bins and hoppers, or where impact is likely to be high. The location of the liner with respect to the trajectory of the material must be carefully considered, in order to present the material flow normal to the surface of the liners as far as possible. Other locations where rubber may be used are in the body of the chute which may be subject to material splash, in order to reduce noise levels. Rubber liners should not be specified in areas where sliding takes place without the introduction of wash water.
General
The bare chute plate should be prepared in accordance with the requirements of the engineer. For replaceable metal liners, the chute surface should be clean and free from rust and scale. The surface to be lined may be coated with epoxy primer to 30 µm. For other methods of attachment, such as adhesives or riveting, the surface of the chute to be lined should be prepared in accordance with the requirements of the liner supplier. All liner plates must be sized for ease of handling, with an average mass of 30kg and a maximum mass not exceeding 35kg. Keep in mind that liner plates are often difficult to manipulate within the confines of the chute body. A recommendation is that liner plate could be provided with removable ‘handles’ to facilitate handling. Metal liners should be secured with countersunk bolts. The maximum bolt diameter is usually determined by the thickness of the liner. The countersunk holes should allow a base thickness of about 3mm between the back of the liner and the underside of the countersink. The maximum securing bolt diameter may then be determined as
d = 2(t-3) mm
(3)
Where
t = liner plate thickness.
Liner plates of thickness 12mm and above should be secured with M16 countersunk bolts.
For any other shape — 4 bolts For other lining materials, the securing bolts or rivets should be in accordance with the requirements of the liner supplier. Nib head bolts may be used in areas that are not subject to flexing or heavy impact. Note that cracks in the harder steel liners originate at the notch for the bolt head nib. For this reason, liners in hardened steels that are subject to flexing ought to be secured with conventional countersunk bolts, with slot heads or hexagonal socket heads. The securing bolts may be grade 4.4. In areas where wash down water is used, the bolt joints should be made water tight. The liners ought to be so patterned that the gaps between the liners are staggered in the direction of flow, in order to prevent the material fines ‘channelling’, and creating ‘pagging’ areas (the rapid build up of very fine material). In corners, the liners must be so arranged that the edges overlap and the corners of the bare chute are protected. Welding of liners is unacceptable. The recommended thickness of steel liners shall be as follows, subject to input from the liner supplier: • 20mm — on high wear, heavy impact areas and chutes handling material of average lump size greater than 100mm to 150mm • 12mm — on surfaces subject to light impact and material sliding only, and on skirts • 10mm — on fines chutes that are not subject to impact. The thickness of other lining materials, such as ceramics and Solidur should be as determined by the liner supplier.
The ‘Between Skirts’ dimension
A very commonly applied standard for the dimension between conveyor skirts is that the dimension between skirts should be 2/3 of the belt width. This dimension was developed for flat feeder belts and remains applicable in this case. However with ever increasing trough angles, applying this simple rule often results in a very small clearance between the belt edge and the skirt rubber. A small lateral movement of the belt causes the belt to push the skirt rubber out with resultant spillage and constant belt tracking problems. G Shortt has proposed a modified rule which is based on retaining the free-board (dimension between belt edge and skirt in this case) distance instead of the ‘between skirts’ dimension.
The minimum number of securing bolts per liner plate should be as follows:
In this case the free-board dimension is premised on the reliable rule for the flat belt condition of one sixth of belt width.
For triangular sections — 3 bolts
Material properties
Knowing the inherent properties of the material BULK HANDLING TODAY
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Figure 7. Skirt width for constant W/6 free-board
loads and with different wall materials, effectively simulating the impact of material on the chute face and the angle at which the impacted material will slide.
The starting point – the material trajectory
The starting point is the point at which the material leaves the discharge pulley. It is important here to identify this position as at this point mechanical interaction between material and belt is lost, and the material acts like a projectile with initial velocity subject only to the action of gravity (excluding the effects of air resistance).
Figure 8. Test for wall friction angle
being conveyed is critical to the successful design of transfer chutes. The obvious properties which would probably have been used in the selection of the required belt parameters to suit the duty are: • The type of material (eg coal) and whether it is abrasive or corrosive • The particle size and particle size distribution (mm) – highly dependent on process • The bulk density
(kg/m3)
• The belt surcharge angle ( °) • The angle of repose ( r°). While many of the above material characteristics are published in manuals and catalogues it is always best to run typical bulk flow tests on the specific material to be conveyed. An important property is ascertaining the point at which the material begins to slide down the chute face for different types of liner material. This is typically established by testing, utilising a system similar to the Jenike Johannsen Shear testing system – however in this case, a force is applied to a block of the material and then the pressure is released and the block tilted until it begins to slide. The test is performed at different
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BULK HANDLING TODAY
March 2016
The material trajectory is fundamental in the design of the chute as it defines the flow of material and the requirements for first impact point and the path followed by the material until it lands. There are numerous examples available in literature defining the methodology to be followed in establishing the material trajectory. The methodology described below is based on the CMA lecture course. There are recent papers presented at Beltcon by David Hastings which are excellent references to other methodologies and which also give a comparison of the different methods against actual results established by high speed photography. The theory being proved by the practical. The methodology proposed in the CMA Diploma Course is as follows: • Establish the area of material flowing over the head chute • Establish the depth of material flowing over the head chute • Establish the centroid of area of the material flowing over the head chute. The condition of material flowing over the head chute is represented below for a typical three-roll idler set. Note that the troughed form now flattens out and the area of the trapezium formed when flattened should be equal to that of the troughed configuration. For a belt loaded to 100% of CEMA and based
BELTCON
Figure 9. Loaded belt profile at the discharge
on normally accepted free-board dimensions, the width of material on the flattened belt may be found from:
The point (R) at which the material stream leaves the belt can now be defined.
Wwet=(0.9W-50)x10-3
Define
(4)
Where
(7)
Where W = belt width in mm
R = (r + h + Ca) in m
r = pulley radius over lagging (m)
And
h = belt total thickness (m)
Wwet is the wetted area in metres
(Note that units are mixed in order to simplify calculations).
Ca = depth to centre of area of material burden (m) At the point of separation, the material has the same velocity of the belt V (m/s)
The centroid of area of the trapezium is accepted as 40% of the height yielding Ca = 0.4 x d
And define factor K
(5)
Setting the area of the troughed belt equal to the area of the trapezium resulting from the flattened belt yields
(8)
Where = angle of inclination of the belt at the discharge pulley. The location of the drop points with their dependency on belt speed is now defined as For K > 1 Drop Point is at T
For K < 1 Drop point is at C
(6 Where A100 is the cross sectional area at 100% loading in m2 And is the angle of repose (typically 34°–37°) With this, a profile can be defined that the centroid of material would follow around the head pulley and along its trajectory with upper and lower boundaries following this path. Note however, that in the case of the material stream comprising mainly large lumps (greater than say, 150mm), it is normal to calculate (d) as a function of the lump size and typically as 60% of the lump size. Figure 10. Point of discharge
BULK HANDLING TODAY
March 2016
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BELTCON
(9)
Where , the angle between the horizontal and the drop point is defined as the release angle. In the case of slow moving belts where the release angle is calculated as being less than the angle of repose of the material, it is normal to reckon the release angle as being between 3–5 degrees greater than the angle of repose of the material. Plotting the material trajectory can now be done • From the drop point determined above extend a line along the inclination determined Figure 11. Trajectory at fast belt speed
• Decide on set-out spacing.
L=Vxt
(11)
where t are time intervals (typically seconds) and mark out • At each spacing along the line of the release angle drop a vertical of distance
(12)
• Join each end point to plot the trajectory of the centre of area of the material.
Figure 12.Trajectory at low belt speed
The upper and lower bounds of the trajectory will follow the upper and lower bounds of the material about the centre of area for a fall of about 2.5m. Thereafter air-drag and wind may result in deflection of the material stream. Figures 11 and 12 indicate the difference in material trajectory for fast and slow belt speeds. Knowing the material trajectory, the flow pattern and the point of first impact can be determined. This is critical in the design of the Hood. The Hood directs the flow of the material towards the Spoon. The material is intercepted at a tangent. The Hood should be designed such that it has the same radius of curvature at the point of impact as the trajectory, ie the impact angle should be as small as possible (Figure 13).
Figure 13. Hood design
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BULK HANDLING TODAY
March 2016
BELTCON
Design priciples for chute design Design Principle 1 – Prevent Plugging at Impact Points The chute face must be sufficiently smooth and steep to allow sliding and hence clean-off of the stickiest material that it has to handle. The impact pressure at any point that the material stream impacts the chute face is given by Figure 14. The velocity following an impact with the chute surface may be calculated from Figure 15.
Belt Interface The stream velocity in the belt direction:
(19)
The vertical component:
(20)
The impact pressure of the stream with the belt
Stagnation and hence plugging will occur when V2 = 0 m/s.
It is critical that the velocity at the point in question be accurately estimated.
As the material moves through the chute it may be subjected to different acceleration forces such as sliding along the chute plates or free falling through the vertical section of a chute.
Design Principle 2 – Ensure Sufficient Cross-Sectional Area
The acceleration along a face of the chute is calculated as a = g (sin
(21)
Always ensure that there is sufficient belt crosssectional area to allow for the free flow of material through different sections of the chute.
– cos .tan ’) (13)
And the velocity is calculated as
(14)
Where V0 is the Velocity at the start of the incline and S is the length of the incline. For Free fall the velocity is calculated as
(15)
Where S is the height of the free fall and g is acceleration due to gravity. For a section of the chute at a slightly different inclination, the starting velocity
Figure 14. Formula for impact pressure
(16) Where ß is the inclination of the section. Acceleration over this section is (17) So that the exit velocity (18) Figure 15. Velocity after impact
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March 2016
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BELTCON
Design Principle 3 – Control Stream of Particles It is critical to retain control of the material flow through the chute in order ensure efficient transfer. The following figures and formulae give the design principles employed with both a material stream falling under gravity as well as that where material exits the chute with significant velocity. The case illustrated in Figure 16 shows slow moving particles exiting the discharge chute and falling through a free-fall vertical portion of the chute onto the curved ‘Spoon’ chute. The flow into the curved bottom section of the chute may be illustrated by the free body diagram in Figure 17. For a chute of rectangular cross-section Figure 16. Chute flow configuration - in line transfer
(22)
Where V0=initial velocity at entry to stream H0=initial stream thickness Analysing the dynamic equilibrium conditions of Figure 17 leads to the following differential equation
(23)
If the curved section of the chute is of constant radius R and μE is assumed constant at an average value for the stream, it may be shown that the solution of the above equation leads to Equation 24 for the velocity at any location
Figure 17. Spoon chute flow model
(24) For v = v0 at
=
0
(25)
Special Case: When 0
=0
And v =v0,
(26)
Equation (24) becomes
(27)
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BULK HANDLING TODAY
March 2016
BELTCON
In the generalised case of a belt conveyor transfer point the material leaves the discharge pulley with some inertia in the horizontal direction and hence the material stream has to be channelled into a cohesive stream and controlled through the vertical section and onto the Spoon chute. This is illustrated in Figure 18. Hence the material flow in the upper Hood portion is represented by the free body diagram in Figure 19. The formulae developed for the Spoon section may be developed for the hood section as (28) For a constant radius and assuming Îź_E is constant at an average value for the stream, the solution for the velocity Equation 18 is
Figure 18. Flow through an in-line transfer chute
(29) For v = v0 at
=
0
then
(30) The above principles may also be applied to the case of a convex curve in the chute as indicated in Figure 20.
(31)
This is applicable for sin It is noted that Figure 20 also applies in this case with the vertical axis now representing the maximum value of the velocity for chute contact. For a constant radius and assuming ÎźE is constant at an average value for the stream, the solution for Equation 29 is
Figure 19. Flow model in Hood portion
(32) For v = v0 at
=
0
then
(33)
Figure 20. Flow in a convex section
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Advanced CRUSHING AND SCREENING Technology
BELTCON
Design Principle 4 – Minimise abrasive wear of chute surface
Impact wear
Consider the generalised case of flow through the Spoon as indicated in Figure 21.
(34)
Wc has units of N/ms NWR is the non-dimensional abrasive wear number and is given by
(35)
The various parameters are Ø = chute friction angle
Kc = ratio Vs = velocity of sliding against chute surface Qm = throughput kg/s
Impact wear in transfer chutes may occur at points of entry or at points of sudden changes in direction. For ductile materials the greatest wear occurs when impingement angles are low, say 15°–30°. For hard, brittle materials the greatest impact damage occurs at steep impingement angles of the order of 90°.
Design principle 5 – Minimise the wear of the belt A critically important aspect in the design of transfer chutes is that of reducing the effects that the material stream has on belt wear and damage. The transfer of material onto the belt is illustrated in Figure 22. The primary objectives are to:
B = chute width (m)
Distribution and Product Support by:
• Match the horizontal component of the exit velocity as closely as possible to the belt speed • Reduce the vertical component of the exit velocity so as to reduce abrasive wear due to impact
R = radius of curvature of the chute (m) V = average velocity at section considered (m/s) = chute slope angle measured from the vertical The factor Kc < 1. For fast or accelerated thin stream flow, Kc = 0.6. As the stream thickness increases, Kc will reduce. Two particular chute geometries are of practical interest, straight inclined chutes and constant radius curved chutes.
Figure 21. Flow through Spoon
Wear on chute side walls
Assuming the side wall pressure increases linearly from zero at the surface of the stream to a maximum value at the bottom, then the average wear may be estimated from ELB EQUIPMENT - HEAD OFFICE: Tel: (011) 306-0700 • Fax: (011) 918-7208 e-mail: Elb@elbquip.co.za www.elbequipment.com Branches & Dealers throughout Southern Africa
(36)
Wear on chute bottom
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Kv and Kc are as previously defined. If, for example, Kc = 0.8 and Kv = 0.4, then the average side wall wear is 25% of the chute bottom surface wear.
An abrasive wear factor WC may be determined as:
® ®
A critical aspect in the efficient design of transfer chutes is the wear that is imposed on the chute surface by the abrasive nature of material flowing on the chute surface.
Figure 22. Feed onto the belt
BELTCON
Figure 23. Non-dimensional wear parameter versus slope angle
• Load the belt centrally so that the load is evenly distributed in order to avoid belt mistracking and spillage.
As shown, the wear is quite severe at low chute angles but reduces significantly as the angle e increases.
The following formulae have been developed as a means of estimating belt wear at a transfer point:
For the chute to be self-cleaning, the slope angle of the chute at exit must be greater than the angle of repose of the bulk solids on the chute surface.
(37)
Where
It is recommended that
p = bulk density
Vey = vertical component of the exit velocity
Conclusion
Abrasive wear parameter Wa:
(38)
Where μb = friction coefficient between the bulk solid and the conveyor belt Vb = belt speed The wear will be distributed over the acceleration length La. The wear parameter may then be expressed as
(39)
Where
(40)
e = chute slope angle with respect to vertical at exit.
Kb is a non-dimensional wear parameter. It is plotted in Figure 23 for a range of
values.
This collection of rules and formulae has been presented as a reminder to the industry that chute design requires a lot more attention that it is currently given. While sophisticated computer software is an essential tool in modern materials handling, the basic design of particulate flow is equally essential where the software is not available. The application of the equations and principles presented should provide the designer and plant engineer with the means to apply these principles in a practical manner and with sufficient accuracy to confidently predict the performance of the chutes. This paper was first presented at the Beltcon Conference 18 in 2015. Copyright is vested with the CMA. www.cmasa.co.za Adriano (Adi) Frittella, AFripp Projects Tel: (011) 486-3077, Email: adi@afripp.co.za www.afripp.co.za Abri Smit, ELB Engineering Services Tel: (011) 772-1437, Email: abris@elb.co.za www.elb.co.za
Make sure to visit the “Bulk Handling Today” stand at the Copperbelt Mining Expo and Conference (CBM-TEC) being held in Kitwe, Zambia from 12 to 13 May 2016 BULK HANDLING TODAY
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Increased Safety Metso has developed a new maintenance platform that increases safety when changing wear parts in jaw crushers. The new, ergonomic and safe maintenance platform is available on all Metso C Series jaw crushers. Metso’s new maintenance platforms consist of hand rails which are also used for lifting the platform, sturdy work platforms and related control mechanisms, enabling them to be precisely placed at the desired height of the jaw opening. “With a small investment, Metso’s new maintenance platform offers a huge improvement in safety when making jaw changes. When the platform is installed correctly into the opening, it holds the jaw in place so that it cannot drop, even if the jaw’s upper mounting hardware is loosened or even removed. The platform is lightweight and it is easy to handle and
adjust to fit the desired level in the crusher cavity,” explains Ilkka Somero, product manager of Metso’s jaw crusher line. “The textured aluminum platform is sturdy, slip resistant and covers the crusher cavity properly to prevent anyone from slipping or getting a leg wedged between the jaws. Due to its light weight, the platform is easy to lift into position and remove, speeding up the work of changing parts,” Ilkka concludes. Metso, Ilkka Somero, Email: ilkka.somero@metso.com, www.metso.com
C-Series jaw crusher’s maintenance platform
Enhanced Level Measurement Technology Emerson Process Management has enhanced its range of level measurement devices. “Uneven surfaces, irregular build-up and harsh, dusty and potentially explosive environments make measuring the level of solids in large vessels problematic, impacting inventory control decisions,” says Asael Sharabi, technical director at Emerson Process Management. “Our enhanced Rosemount instrumentation meets these challenges to provide users with greater control of inventories and entire manufacturing processes, with significant financial benefits.” Supporting manufacturers’ need for improved inventory control, the Rosemount 5708 Series 3D Solids Scanner, which uses acoustic measurement and 3D mapping technology to provide highly accurate continuous level and
volume measurement, is now suitable for a broader range of applications. The device is now ATEX/IECEx certified for installation in areas with potentially explosive atmospheres, often found in solids measurement applications. A new mounting adaptor also allows the device to be installed within electrostatic precipitator (ESP) hoppers. By using its 3D visualisation capability to map out the surface of the fly ash that builds up in the hopper, operators can optimise the process, reducing cost, risk and wear and tear on the hopper. Emerson Process Management Michael Eksteen Tel: (011) 451-3700 Email: Michael.Eksteen@Emerson.com www.Emersonprocess.com/MEA
New Finance Programme JCB, the world’s third largest construction equipment manufacturer, has formed a strategic alliance with ABSA Bank Ltd acting through its Vehicle & Asset Finance division (ABSA) under the trading name of JCB Finance in South Africa. The new JCB finance programme will be available to all of JCB’s dealers in South Africa. David Dolbear, general manager finan-
cial solutions Africa at JCB states, “The introduction of JCB Finance to the South African market will help us to deliver innovative financial solutions to the construction, agricultural and industrial segments of the market. The combination of our excellent South African dealers with their strong customer focus and outstanding service pedigree, together with the extensive reach and excellent market reputation of ABSA, make this
a perfect combination to increase JCB’s penetration into the South African market through the JCB Finance programme. “Making sure our customers and dealers have access to a complete range of flexible finance products at the most competitive rates underpinned by excellent customer service will help to drive our ambitious future growth plans.” JCB, www.jcb.com
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MARKET FORUM
Mobile Harbour Cranes Liebherr Maritime Cranes recently delivered a LRS 545, the first model out of the new reachstacker series, to the Italian Port of Ravenna. The LRS 545 is the latest cargo handling solution from Liebherr and as such benefits not only from the company’s collective maritime experience, but also from its expertise in the fields of engine architecture and system control software. The new reachstacker series design is based on the latest technology in order to maximise driver’s comfort, performance and eco-friendliness. The LRS 545 is equipped with a 4 cylinder, 230 kW Liebherr diesel engine. This downsized engine protects the environment by low fuel consumption and reduced emissions. To fulfil stage IV and tier 4 final legislative requirements, Liebherr relies entirely on an innovative SCR (selective catalytic reduction) system. The inhouse-developed system reduces exhaust emissions effectively without sacrificing performance.
The reachstacker is designed for low maintenance. Service intervals of 1 000 operating hours provide the necessary reliability and peace of mind for the engineers on-site. Remote access and remote technical assistance in order to
analyse data and carry out troubleshooting are possible via the internet. Liebherr Maritime Cranes, Philipp Helberg, Email: Philipp.Helberg@liebherr.com, www.liebherr.com
Refurbished Crane The Lifecycle of Lifting Equipment Konecranes’ local technicians focus on the entire lifecycle of the crane to help improve the safety and productivity of customer operations and reduce the cost of crane ownership over the lifetime of the crane. With insights on local requirements and evolving crane technology on all types of cranes, the company has developed a comprehensive maintenance program that supports long-term safety and performance. Konecranes offers a variety of consultation services that can provide a deeper analysis of a customer’s lifting equipment and help identify improvement oppportunities. “We don’t just drop off a report on our
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BULK HANDLING TODAY
way out, but take the time to share our findings and discuss how each action impacts the operation of our customer. With our industry-leading technology and non-destructive testing, we can uncover latent or hidden defects with minimum disruption,” says Konecranes service and marketing manager, John MacDonald. With an extensive service offering that delivers lifecycle care and a worldwide network of support, Konecranes has the experience and resources to help meet customer objectives, globally and locally in South Africa. Konecranes, John Macdonald, Tel: (011) 864-2800, Email: John.macdonald@konecranes.com
March 2016
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Boost for Copper Mining
The current challenges facing Zambia’s copper mining industry brought about by a global downturn and declining commodity prices are further fuelled by general increases in operating costs. The Zambian mining industry is collaborating to find a long-term strategic solution to promote the growth of not just the mining industry, but the economy generally. A 36m, 30-ton scrap handling crane located at the Vanderbijlpark site of steel giant Arcelor Mittal has been successfully refurbished by Demag, as part of a crane modernisation and modifications (CMM) project. Demag was tasked with refurbishing the scrap handling crane, which is re-
Copperbelt Mining Trade Expo and Conference (CBM-TEC). “Mining companies are fighting to preserve operations through cost cutting and optimisation initiatives,” says event director of CBM-TEC, Nicole Smith. “At the same time, to ensure readiness for the upward turn of the copper price and commodity demand, investment has to continue in exploration projects that will translate into viable mining operations in the future. The show will not only focus on the mining industry, but will also highlight related industries such as engineering and manufacturing. Power and water will also be in the spotlight at the show.”
Although the outlook remains positive for copper demand to increase and for underlying market conditions to support higher prices from 2017/18, which will bring in a new cycle of production and operations ramp-up, solutions need to be found for the short term. Zambia’s copper mining industry will receive a boost in May this year with the hosting of the third edition of the sponsible for picking up scrap with magnets and moving it into a furnace. “The project was undertaken in August 2015 and completed within a month. It required four men onsite and took us 20 working days to modify the whole crane. The process included taking the crane apart, replacing obsolete components and welding the inside to suit the new gearbox. Upgrades represent an important investment in the performance of an existing crane, and serve as a cost-effective measure that reduces the possibility of downtime significantly,” explains Demag project
CBM-TEC is a professional attendance mining technical supplies and equipment trade expo for the Copperbelt region, hosted exclusively within the Copperbelt. The show will take place on 12-13 May 2016 at the Kitwe Showgrounds. Specialised Exhibitions Montgomery, Leatitia van Straten, Tel: (011) 835-1565 Email: leatitiavs@specialised.com, www.cbm-tec.com
engineer, Antonio Da Costa. Demag offers a wide range of products and services such as repairs, maintenance, inspections, training, refurbishments, overhaul and consulting. The company also manufactures products such as cranes, hoist units for safe load handling, drive solutions, components, accessories and KBK-light crane systems for load capabilities of up to 3 200 kg. Demag Cranes, Antonio De Costa, Tel: (011) 898-3500, Email: enquiry.sa@terex.com, www.demagcranes.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 two through to 100 guests in nine 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, business centre, fibre optic broadband AV, lockable space, and an onsite Hair & Beauty Boutique, 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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Safety Nets
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Due to the intricate nature of their work, testing laboratories at the South African Bureau of Standards (SABS) can often not be shut down during renovations and maintenance, and temporary supporting structures not only come with a considerable financial burden, but limit daily activities too. Safety and work platform nets have proven
to be the most effective fall protection solution for Enza Construction, which has been contracted to install ducting at an SABS testing facility, while ensuring that no disruptions are caused on the laboratory floor. Two 6m x 4m safety nets were installed 6m off the ground by rope access specialist, Skyriders, in early November
2015. Marketing manager Mike Zinn indicates that a four-man rope access team successfully installed the nets over a two-day period. “Using slings, the Skyriders team secured the nets to parallel crawl beams that were already secured to the concrete soffit. In certain areas, chemical anchors were placed onto the concrete to ensure greater anchorage,” he explains. Chemical anchors are made up of steel studs, bolts and anchorages which are bonded into concrete, using a resin-based adhesive system. It is ideally-suited for high-load applications. “The chemical anchors were left to cure for 24 hours before installation commenced,” adds Mike. “When installed correctly, safety nets hold up under the toughest demands. In this case, the nets not only ensured construction worker safety, but also enabled SABS testing centre activities underneath the work space to continue uninterrupted, thereby eliminating downtime,” he concludes. Skyriders, Tel: 086 100 0759 SKY (759), www.ropeaccess.co.za
Terminal Tractors
New to BLT SA’s range of materials handling equipment are Capacity Sabre 9 terminal tractors which are coupled with trailers to safely move heavyweight trailered cargo throughout container terminals, across docks and over airport runways. “Critical challenges facing the logistics sector include efficient cargo handling solutions that reduce operating costs,
improve productivity and enhance safety of operations,” says Charity Gumede, marketing director, BLT SA. “Capacity terminal tractors ensure faster handling times, reduce on-site congestion and minimise demurrage costs for trucks waiting to be loaded and unloaded. By positioning trailers at discharge ramps, the road truck is able to transport further loads, instead of having to wait for a
trailer or container to be discharged. Capacity Sabre 9 terminal tractors have a robust frame construction and precise manufacturing tolerances, ideally suited to handle rigorous operations. This series has been designed with a 30% faster actuation of the boom than previous models. The advantage of this is reduced coupling times which enables quicker drive-aways. A lower, tapered skid ramp minimises trip outs of the cab and for increased operator safety, there is a lower step height and new sight line designs for improved visibility.
Built-in onboard diagnostics enable operators to easily monitor the machine’s service status. Numerous service checks can be performed at ground level, which ensures more uptime for each machine. BLT SA, Charity Gumede, Tel: (031) 274-8270, Email: info@blt.co.za www.blt.co.za
BULK HANDLING TODAY
March 2016
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MARKET FORUM
Port Security System Transnet National Ports Authority (TNPA) has introduced a state-of-the-art port security system valued at R843 million to safeguard customer cargo, port users, as well as Transnet’s own port assets, staff and contractors. Phumuzi Sigasa, head of TNPA’s port security portfolio says “In conformance with regulations and our own Integrated Security Management Systems-Security Strategy Plan, we are rolling out an upgraded security system across our eight South African commercial ports and our head office in Johannesburg. CCTV is but one aspect of our broader integrated technological security system which encompasses technology, skills, systems and procedures.”
Quality Replacement Parts The growing cost of maintenance, especially with the current exchange rate issues, has spurred an increase in the use of low cost, low quality spurious replacement parts. Andrew Yorke, director at Metric Automotive Engineering, says that this is especially true in sectors such as earthmoving and mining equipment, where maintenance costs dominate the lifetime of equipment. “While many service providers stake their hard-earned reputations on extending the life of a machine, there are those who are less ethical and see an opportunity to make a larger profit. Add to this scenario that some buyers within the larger organisation may not actually understand
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BULK HANDLING TODAY
the long term ramification of using sub-standard replacement parts,” says Andrew. Metric Automotive Engineering can refurbish large diesel engine components and offers services such as cylinder head remanufacture, cylinder block line boring, milling, honing and boring, camshaft grinding, crankshaft grinding, engine assembly and dynamometer testing. Subsidiary Reef Fuel Injection Services offers Bosch, Delphi and Denso approved fuel injection services and is acknowledged as the specialist in CAT fuel systems. Metric Automotive Engineering, Andrew Yorke, Tel: (011) 873-2350, Email: andrew@metricauto.co.za, www.metricauto.co.za
March 2016
The CCTV system will be integrated between all port sites and the head office to give a bird’s eye view of the port security environment. It comprises 2 100 high definition cameras across the various sites, as well as long range cameras to monitor all port channel entrances and outer anchorages. The newly renovated control room located at the Port of Durban boasts state-of-the-art video walls for added visibility across the port. Vehicle security within the port perimeters will also be enhanced through licence plate recognition. The system will also facilitate increased night visibility through thermal imaging that can detect heat emitted by objects or bodies, especially in low visibility areas and through smoke, fog and haze. Some of the most common security incidents in South African ports can include stowaways, theft of cargo and damage or theft of assets owned by Transnet and other port users. Transnet National Ports Authority (TNPA) Tel: (011) 351-9013 www.transnetnationalportsauthority.net
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Screen Replacement
The recent supply of a complete resonance screen with an additional screen box to an Australian iron ore mine underpins MBE Minerals SA’s drive to participate in global markets. The supply of these screens is the continuation of the screen replacement programme of 20 such machines for this major Australian iron ore producer.
“Significantly, the original screens were manufactured in South Africa by MBE Minerals in 1997 and have been operating successfully in a fashion that is typical of their reputation for extended life cycles in arduous hard rock applications. We can reference a number of enduring heavy duty vibrating screen installations in the iron ore sector, including ones in the South African Northern Cape that have been in operation for more than 40 years,” says Johannes Kottmann, managing director of MBE Minerals SA. The 2.4 by 4.5 metre screen employs the
principle of resonance and dynamic vibration adsorption for its screening action. “A number of design elements have been incorporated to enhance performance, including the operation of the screen box at near resonance frequency. This allows the actuating device to replace only energy lost to the oscillating system by mechanical resistance and material transport,” Johannes explains. “Our screens are manufactured to provide increased throughput, while at the same time reducing both downtime and maintenance costs. Leveraging an extensive footprint of products for sizing, scalping, dewatering and media recovery, we are able to customise each screen to the specific requirements of the customer’s application,” Johannes concludes. MBE Minerals SA, Johannes Kottmann, Tel: (011) 397-4660, www.mcnallybharat.com
Auto Level Feature Superior Industries, Inc, has released new technology that allows its TeleStacker Conveyors to maintain level movement while in radial travel mode. This technology allows the telescopic radial stacking conveyor to maintain a balanced conveyor structure. As a result, the TeleStacker Conveyors belting is less prone to mistracking. Uneven conveyor structure, says Superior, is one of the leading causes of inaccurate belt tracking. Auto level technology is standard on all FD Axle model TeleStacker Conveyors equipped with PilePro Automation. Superior manufactures FD Axle models in lengths of 33.5m, 39.6m, 41.5m, 45.7m and 48.0m. Superior Industries, Corey Poppe, Email: corey.poppe@superior-ind.com, www.superior-ind.com
workhorse boasts a lifting capacity of close to 1700 kg and is capable of safely handling tyres on any large vehicles or machinery operating in construction, mining, agriculture, forestry, and general industry.
Safe, No Fuss A first in South Africa, the unique and robust Bobcat industrial wheel mover has been specially designed and engineered locally to ensure the safe, easy and efficient removal and perfect positioning of large wheels with diameters ranging from 36” to 90”. Weighing 214kg, this
According to Bobcat Equipment’s national sales manager, Andre Steenkamp, “Changing or moving a large heavy tractor tyre or even sprayer tyres is simply no fuss with the new attachment. In addition to safety and convenience, this innovation can deliver massive savings to the end-user. Instead of having to halt production to commit an integrated tool handler or front end loader to remove a wheel, we offer companies a dedicated
purpose-built attachment to do the job.” The wheel mover attachment has no hydraulics and can be fitted to a pallet fork or connected with a standard Bobtach for skid steer loaders. The attachment features a right lean safety bar as well as a safety arm which is adjustable from side to side to fit around fenders and also holds the tyre in place during transportation. Three rollers fitted on each side facilitate tyre rotation. The attachment’s economic design ensures very few wear and tear parts and features remarkably low operational and maintenance costs. Bobcat SA, Email: bobcat@goscor.co.za, www.bobcatsa.co.za
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Bulk Bag Discharger
one hopper to be filled and discharged, while the other hopper and metering valve are cleaned.
A new Bulk-Out Bulk Bag Discharging Station from Flexicon prevents cross-contamination during material changeovers, while eliminating downtime associated with cleaning of hoppers. Beneficial for applications involving food allergens, pigments, flavourings and other contamination-sensitive materials, the discharger features a shuttle system that allows a hopper that has been used, to be exchanged for a clean, dry hopper in less than one minute. Each hopper is equipped with a stainless steel rotary valve that meters material into process equipment positioned below the mezzanine. Once empty, a hopper can be rolled within two C-channels to either side of the central filling position for sanitising offline. Integral support rails on the rotary valve allow the rotor assembly to separate from the valve body for cleaning of all material contact
The assembly consisting of the clamp ring, telescoping tube and quick-release cone hopper lid, provides unobstructed access to all material contact surfaces for rapid cleaning during material changeovers. The model “BFC” discharger is distinguished by its cantilevered I-beam with electric hoist and trolley that allows raising and positioning of bulk bags without the use of a forklift.
surfaces, and to close securely in seconds without the use of tools. The hopper shuttle system can more than double productivity by allowing
Construction is of carbon steel with durable industrial finish, with all material contact surfaces of stainless steel. Flexicon Africa, Tel: (041) 453-1871, Email: sales@flexicon.co.za, www.flexicon.co.za
Call for Papers The International Materials Handling Conference (IMHC) invites authors and speakers to submit a synopsis on topics relating to belt conveying for presentation at the nineteenth Beltcon Conference in August 2017, to be held over two days in Johannesburg, South Africa.
has earned a well-deserved reputation as the reference point for information sharing, discussion of new developments in the industry, and the latest in design, research and case studies presented by world renowned academics and leaders in the field of belt conveying.
The Beltcon Conference is regarded as a leading international forum for presentation of the latest technology, design, research and relevant case studies in conveying.
Papers are in two parts: Technical papers are issued in hard copy to each delegate as Conference Proceedings. These are later published as Past Papers. Each speaker presents the content of the technical paper in a PowerPoint presentation at the conference.
* T he conference is conducted in English.
sign is essential to ensure operational characteristics are matched throughout the plant. By custom designing each transfer point, individual Weba Chute Systems can be configured to suit each
wear, while the tumbling or rolling motion causes far less wear. We have taken this a step further by designing the internal angle of the transfer chute to match the product with the belt speed and in so doing product degradation is greatly reduced or completely eliminated,” Mark adds.
This conference has been held every two years over the last thirty eight years and
Eliminating Material Degradation Conventional chute design is often associated with the uncontrolled discharge of bulk materials, which is linked to increased material degradation. Mark Baller, managing director of Weba Chute Systems, explains that a systems approach to bulk solids handling de-
particular application. “Our system uses a ‘supertube’, with a cascade scenario, where 95% of the material runs on material at the same time in a tumbling motion, rather than gliding down the chute. We have found that gliding particles cause extensive
* Only papers that meet stringent quality standards are accepted. * Ideally, papers should contain new and unpublished material. * No advertising or commercial publicity to be included.
Please submit a brief synopsis by 30 April 2016 to: Chris Townsend, IMHC Organising Committee, Fax: 086 503-4524 Email: ctr@beltcon.org.za www.beltcon.org.za
The Weba Chute System uses a streamlined scientific approach to the dynamics of bulk materials handling taking all aspects such as belt speed, belt width, material size, shape and throughput into account. The custom design allows control of the direction, flow and velocity of a calculated volume and type of material in each individual application and at the same time drastically reduces dust. Weba Chute Systems, Mark Baller, Tel: (011) 827-9372, www.webachutes.com
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Improving Productivity Rio-Carb has ensured a saving of more than R100 000 for a power plant in Secunda, after successfully refurbishing three chutes and fitting them with Chromium Carbide (CrC) liner plates. Rio-Carb director Martin Maine explains that the project, which has been ongoing for five years, was extended due to the impressive performance of the R-C 700 liner plates. “Rio-Carb had already installed liner plates, in the three 60 m2 chutes at the plant. We have also been tasked with supplying the utility with R-C 700 pipes, which outlast the current pipes ten-fold.” The chutes at the plant were previously
fitted with ceramic 2m bolted liners, which were not suitable for the project’s specific wear rate, thereby resulting in erosion and blockages in the chutes. Rio-Carb replaced ceramic liners with 500mm x 500mm R-C 700 liner plates, which are manufactured to the chute specifications. The refurbishment included; sandblasting, welding and refitting. Rio-Carb repaired the holes in the chutes, and then standardised the liner sizes to an easy-to-handle weight.
MaxCS technology, Rio-Carb is able to take the properties of CrC and cast it via a welding process onto a mild steel backing plate, which gives it an optimum hardness of 58 RC, and additional flexibility for moulding and shaping.
Standard refurbishments cost at least R2-million every three months, while with Rio-Carb’s R-C 700, it is around R1-million every three years. Using
Rio-Carb, Martin Maine, Tel: (011) 908-1014, Email: info@riocarb.co.za, www.riocarb.co.za
The liner plates are also marked with a unique identification number and recorded in the company’s database. This enables the customer to get the correct liner plate sizes immediately, and eliminates the need for onsite measurements.
All-in-one ifm electronics’ new RFID compact unit with CANopen interface has been developed for identification tasks in agricultural machines, municipal vehicles and construction machines.
responding settings in the controller which simplifies the creation of userspecific systems set-ups. Downtime is minimised and productivity is increased.
compact M18 or M30 stainless steel housing with an extended temperature range of -40-85 °C. The unit is available for all common frequency ranges with shock and vibration resistance.
It automatically detects different attachments and configures the cor-
With a protection rating of IP67 and IP69K the RFID unit comes in a
ifm electronic ZA, Alwyn Skelton, Email: info.za@ifm.com, www.ifm.com
Index to Advertisers PPS 30
The Peartree
40
CIS 20
RFA Convention
44
Torre Lifting Solutions
16
Dymot Engineering
39
Sandvik
Inside Front Cover
Weba Chute Systems
15
ELB Equipment
34
SEW Eurodrive
Inside Back Cover
Worley Parsons
22
Melco 42
Tega Industries
Outside Back Cover
Powermite 18
Tenova Takraf
Outside Front Cover
Breakbulk Africa
46
BULK HANDLING TODAY
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