Modern Mining May 2022

in hard rock mining applications

gap between the rollers sideways. The self-adjusting cheek plates maintain the pres sure in the operating gap and always ensure a tight seal. “Combined with our tailored edge studs, our self-aligning cheek plates provide an optimal seal, reducing accelerated wear in the roll edges and lowering energy consumption in the process,” says Mtsweni. “What makes our lateral wall system unique is that it is spring-loaded, which not only reduces the edge effect, but also facilitates roll skew. Having one roller skew facilitates larger material at one end while ensuring the smaller particles on the other side receive enough pressure to be ground down,” adds Hendricks. Long roll life is another attribute of the Enduron HPGR technology. The longevity of roll life, says Mtsweni, is essential to the overall performance of the processing plant – both in terms of availability and operating costs. Stud selection is critical to the long life of the roll and to align roller life time with scheduled mainte nance shutdowns of downstream equipment. Weir Minerals’ expertise and extensive portfolio of stud grades and designs caters for the needs of spe cific applications. “The Enduron HPGR technology has thus been proven to offer significantly higher roll life than the competition whilst minimising ineffective usage of tungsten carbide, which aligns with our ESG strategy. In addition, as a result of our compact bear ing arrangement, we are able to deploy longer rolls combined with a compact diameter, which enhances grinding efficiency and reduces infrastructure costs, keeping structural height to a minimum,” concludes Mtsweni. 

across the rollers; maintaining optimal pressure and exceeding the ore’s compressive strength across the entire feed. This is required for the rocks to break effectively, and to minimise power consumption and reduce recirculating load, even at segregated and changing feeding conditions common to real life ore processing. “The overarching benefit of the unique bear ing arrangement is the long bearing life, ensuring greater than 95% machine availability, which directly results in increased product yield. Enduron® HPGR customers can have peace of mind with bearing life guarantees greater than 10 years, combined with overall machine and process guarantees de-risking the heart of grinding circuit.” says Mtsweni. Another unique feature is the control philosophy. The efficiency of HPGR technology is largely depen dent on how you feed it, explains Mtsweni. If not fed properly, it is unlikely to achieve the required grind and throughput. “Our unique control philosophy comes with mul tiple start-up and shut-off kits. These eliminate an abrupt start-up process by enabling a smooth and steady ramp up of material onto the rolls,” says Mtsweni. “Material first reports to the start-up gate, which allows for a shorter drop-off height from the feed bin and reduced peak torque loads, thus elimi nating potential roller surface damage and avoiding motor trips.” HPGR reduces particles by compressing the feed material between two equally sized, parallel counter-rotating rolls, of which one is hydraulically pressurised. To compensate for the edge effect, a lateral wall or ‘cheek plate’ is deployed on either side of the Enduron HPGR to prevent material exiting the

Weir Minerals can optimise and tailor durable studs to suit the application.

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May 2022  MODERN MINING  33