The mining sector relies increasingly on Engineering, Procurement and Construction Management (EPCM) firms for new builds and expansions, allowing miners to focus on their core mandates. The advantage of using EPCMs is their design and execution capability, which many mining companies have elected to reduce over the years. According to Weba Chute Systems project manager Ted Cruikshank, this usually streamlines the input of suppliers, allowing for a focused and efficient relationship.
“For EPCMs to get the best value from our decades of experience in transfer points, they really need to talk to us early in the project cycle – ideally at bankable feasibility stage,” says Ted. “This can ensure that transfer points are optimally planned upfront, as the positioning of this infrastructure is vital to many other aspects of the plant.”
A spanner in the works
He notes that in the past five years or so, there has been a growing recognition that transfer points and chutes have a significant impact on the overall performance of process plants. They were previously considered as relatively small additions to plant layout, with more attention being paid to the larger items which carried a higher capital value.
“What is now being appreciated is that poorly-positioned or inadequately-designed chutes can disrupt the entire plant process, costing mines dearly in terms of downtime, maintenance and repairs,” he says. “Mines pay the price of sub-standard equipment by having to deal with choking in the chutes, high wear-and-tear, spillage, skew belt loading, damaged idlers and other problems.”
These challenges can be avoided if EPCMs engage transfer point specialists early on, so that these experts help inform the plant layout before final design decisions need to be taken. By getting the right input in good time, EPCMs can also quote more accurately on their project costs.
“For instance, if the positions and heights of key equipment in a plant have already been decided before we get involved, it means that designs must be altered in order to achieve optimal results,” explains Ted. “Alterations to existing plans invariably means added costs which the end-customer is never happy about. By arriving at the right design first time around, the costing is more predictable and the reputation of the EPCM enhanced.”
Not just simple platework
He notes that the height of a transfer point is an important variable in properly controlling the flow of ore through chutes and onto receiving conveyors with optimal belt loading, low impact and reduced wear. Before design stage, Weba Chute Systems gathers detailed technical information from the client on the mine’s material characteristics, lump sizes, tonnages, particle size distribution and other factors. Transfer chutes can then be custom-engineered to the right configuration, matched to the ore that needs to be moved.
“We regularly see situations on mines where this process has not been followed, and where chutes are still regarded just as simple platework,” he says. “On one manganese mine in the Northern Cape, management called for our assistance when material flow across the operation became disrupted by dysfunctional chutes that would not last.”
The success of Weba Chute Systems’ intervention in this case led to them replacing almost 30 chutes on a single site, so that mine operations could resume normally. Ted also emphasises the maintenance-friendly design of the company’s chutes, for safer and quicker maintenance.