Plant Equipment and Hire November 2019 | Page 26

plants, for example, needs consistent stockpiles of coal which can be reclaimed to ensure the process never stops, and for that, one needs efficient and effective stackers. Stackers come in a variety of shapes and sizes – fixed, travelling, luffing, slewing and a combination of the options. A travelling luffing and slewing stacker can serve two parallel stockpiles to the left and right of the stockpile yard conveyor. Controlled remotely, it can build a stockpile in chevron, cone shell, strata or windrow stockpiling modes. German conglomerate thyssenkrupp’s South African office designs and manufactures their stackers locally and the company custom designs the equipment according to their client’s specs. The company recently delivered a 2 000tph, 100m long, including the tripper, custom-built, stacker to a coal mine in the Waterberg region of South Africa. The machine weighs more than 300 tonnes and was designed and manufactured in South Africa. Their stackers are deployed across Africa at bulk mining operations ranging from Impeccable management of stockpiles using stackers at Kumba’s Sishen iron ore mine. iron ore to manganese and coal. Steyn says custom building stackers are important especially for mines with existing infrastructure already in place where factors such as rail gauge specs and existing stockpile width needs to be considered. “When designing a brand- new plant, on the other hand, one can invest in a standard stacker, which has obvious cost savings related to design and overall delivery time” he says. Maintenance is critical Stackers are normally designed for the life of mine. However, Steyn says that general maintenance is required to ensure the machine remains in a good working order. “If these machines are properly maintained, they will continue working for 40 years plus, but then you need to look after them. Part of our customer service includes a structural inspection and analysis, which is something clients often neglect. Clients tend to service mechanical, hydraulic and electrical components that can actually be replaced with relative ease. If a major structural component on a stacker however fails, it could be a massive undertaking to replace it or may even result in the scrapping of the machine, not to mention the cost of lost operation. As the world changes, old equipment only needs to be upgraded to remain as relevant as ever. Even if the mechanics of stackers has not undergone radical change, the machines are destined to be with us for many years to come, even as we enter the fourth industrial revolution. thyssenkrupp remains at the forefront of designing and manufacturing stackers from 50 to 20 000 tons per hour and boom lengths from 10 to 65m, and despite a challenging environment, their products continue to stockpile bulk material across the continent. 24 INDUSTRY EQUIPMENT: MINING NOVEMBER 2019 www.equipmentandhire.co.za