The expansion of an underground crusher station at a platinum mine in Zimbabwe has required South Africa-based Weba Chute Systems to provide 10 more of its custom engineered transfer chutes.
Overseeing the contract for Weba Chute Systems is project manager Ted Cruikshank, who explains that the design, manufacture and delivery of the units is already 80% complete. Over the past 20 years, the company has installed approximately 70 chutes for this customer.
“The chutes being supplied in this latest contract will feed run-of-mine material from the ore pass to the underground crusher, as well as from the crusher to the outgoing conveyor,” says Cruikshank. “This has involved designing and building chutes ranging in height from two metres to six metres.”
Before the crusher, the chutes take large material of up to 650 mm in size from a vibrating feeder, at a maximum tonnage of 1,100 tph. Other chutes take the feeder’s undersize, which is smaller than 180 mm in size, at 550 tph. Some of the chutes will also be used in conveyor-to-conveyor applications; these feed 1,500 mm wide belts with up to 1,350 tph of material with a maximum lump size of 250 mm.
“The abrasiveness of platinum ore makes our chute design philosophy – based on the cascade system – very important,” he says. “Our use of dead boxes on the inside of the chute creates a layer of ore for the moving material to flow over – thereby extending the wear life of the chute itself.”
Replaceable lips on the dead boxes become primary wear parts, which can be easily and quickly swopped out at the necessary intervals. By controlling the flow of the mined and crushed material, the chutes facilitate smoother transition and central loading onto conveyor belts, in turn reducing wear, damage and spillage.
“The chutes also include inspection doors for easy access during maintenance,” he says. “To promote optimal uptime for the customer, we are also including a spare set of wearing lip liners for each chute. These are vital for securing the material layer, while ensuring that the dead box itself is protected from undue wear.”
Weba Chute Systems’ agent in Zimbabwe, the locally owned firm Hilmax, will supervise the installation of the chutes.