When the sun rose in India on the morning of 2 November 2018, it marked a full year since FerroCer® panels had been installed at Hindustan Zinc Ltd (HZL). In other words, the mine had experienced precisely zero wear-panel related downtime in a complete calendar cycle. That is a significant improvement on the previous 40mm-thick manganese steel liners, which had a life span of only 23-25 days – meaning frequent replacement and downtime. The FerroCer panels continued to last for over another 100 days, eventually getting replaced after 480 days in the high-impact wear zone in a U-13 tripper chute after the primary crusher at their RA Mines Stream-1.
Responding to a customer pain-point
Before FerroCer, one of the challenges faced by HZL was the high wear in the material transfer chutes. The material handling system needed to be frequently shutdown so the worn-out liners could be replaced with new manganese steel liners, which weighed about 50kg each. Because of the elevated location of several chutes, replacement of the liners required safety preparations (such as scaffolding and other access and handling arrangements), with five to six workers required to get inside the chutes to handle the liners. The manganese liners had a typical lifespan of under 25 days, leading to regular downtime and increased costs.
FLSmidth visited officials at Rampura Agucha Mines in June 2017 and recommended FerroCer wear panels to address the high wear issues in the material handling chutes.
Each panel comprises a set of abrasion-resistant ceramic inserts enclosed in a matrix of malleable steel, which ensures only the top surface of the insert is exposed to material impact. The sides of the inserts are tapered within the matrix, keeping them in place and preventing material particles and fluids from damaging the panels.
Impressive early results
Some in-situ results from the 220-day mark showed that the wear on the panels measured only 8-10mm and had withstood approximately 15 lakh [1,500,000 tonnes] of Lead Zinc ore conveyed through the U-13 tripper chute. This means FerroCer outlasted the previous panels by over 10 times, meaning a much longer replacement cycle, Hindustan Zinc Ltd are clearly delighted with this outcome and are now looking to use FerroCer impact wear panels across their high-impact wear locations. The change from their previous solution has been enormous.
Before FerroCer, the mine had been using manganese liners that needed to be replaced frequently, which obviously involved downtime and cost. After hearing about FerroCer's trial results, they decided to implement the solution in a high impact wear zone in a U13 tripper chute, after the primary crusher at the RA Mines Stream in India.
The results have been impressive, according to Praveen Bhardwaj, Assistant General Manager (Mechanical), HZL - RA Mines, Rajastan: “FerroCer has reduced maintenance time due to the much longer replacement cycle, eliminated possible damage to the mother plate and spillage of material due to the highly abrasive nature of ore, and significantly reduced safety hazards. HZL intends to install FerroCer impact wear panels in all the high impact wear locations.”
FerroCer continues to perform on site
Because of their long-lasting durability, FerroCer panels are perfect for hard-mineral mines such as nickel, gold and copper – and they are proving their worth at site around the world. The results at the Hindustan Zinc site follow on from results from two mines in Australia. One mine operated for more than a year without replacing its wear liners and the other site is on the same track, approaching its first year without the need for liner replacement.
Meanwhile in a Peruvian copper mine, 24 smaller and lighter FerroCer panels, each made of steel plates with ceramic inserts, replaced 6 generic liners. After a total of 12,600,000 tonnes passed, with a feed of 7,500 tph, wear was no more than three percent. At that rate, FerroCer lasts at least 10 times longer than the most expensive and recognised wear liner on the market.