5 Years & 15 Million Tonnes Of Granite Later...

“This installation proves that the lowest priced quote is not always the best in the long run,” said Kingfisher MD, John Connolly. “We were called into Mountsorrel, along with a number of other suppliers, as Lafarge were planning to increase the capacity of its rail head storage system to double the throughput of granite. The problem the company faced in achieving this objective was the nature of the material itself. The granite handled at Mountsorrel is among the hardest known. Unfortunately, this fact was being brought home by the excessive levels of wear that were being experienced in the storage hoppers and conveyor transfer points at the railhead. The existing steel and rubber liners used within the system were not lasting six-months, due to the high levels of impact and sliding induced abrasion from handling of the granite. This was resulting in high maintenance and repair costs, as infrastructure needed replacing frequently.

Clearly, greater service life from the chosen lining system was required if throughput from the hoppers and the transfer system was to be increased: and this increased life would also mean reduced maintenance of the plant. We were asked, together with competitive suppliers, to quote for a system that would achieve these objectives. When we surveyed the hoppers we saw that a two-stage wear protection system was required.

This was needed due to the different levels of wear experienced throughout the system. The top section of the sloping walls of the storage hoppers were subject to sliding abrasion, but the bottom sloping walls and discharge sections suffer from both sliding and impact induced abrasion.
The combination that we chose had proven itself over long periods in very demanding applications. It comprised of our 40mm thick K-BAS, cast basalt lining, for the top sloping section of the hopper sides, and our 50mm thick 92P K-ALOX ceramic liners on the high wear areas in the bottom sloping and discharge chute sections.

The K-BAS fused basalt lining is designed for conveying and storage systems that require high resistance to friction induced abrasion. The material has an extremely hard and smooth surface, which offers the added advantage of improving material flow.

The 92P K-ALOX liner used in the discharge section is in the form of high alumina ceramic tiles. These are easy to shape and fit, and have a smooth low-friction surface that progressively polishes during use, preventing material build-up and improving material flow.

Having had previous experience in combating the problems in storing and handling granite in quarries, on board self unloading sea going vessels and at process plants were granite was used to produce asphalt, we had a good understanding of what worked and what didn’t. The experience was vital to the decision making process which in 2007 lead to us offering a system that we, unlike others, felt confident in guarantying. Our quotation was not the lowest received, but as we were prepared to warranty our system for 10-years of operation, during which – all things being well – some 30 million tonnes of granite would be processed, then the ROI factor played an important part in Lafarge deciding to award us the contract.

After detailed planning, engineering and procurement of raw materials our own engineers installed the lining system on all 20 storage hoppers and various transfer chutes, during a shut down period in compliance with CDM regulations and Lafarge’s strict safety culture. Five years later, the warranty inspection was due, to identify any areas of concern. This was carried out in late February 2012, and the findings were highly satisfactory. The installation looked largely ‘as new’; the only difference from the initial installation being the highly polished nature of the lining surfaces, thus assisting material discharge.”

Upon speaking to the an engineer from Mountsorrel, he said, “We were repairing the old lining system within the original hoppers all the time and also having to patch the structure itself, however, since Kingfisher installed their ceramic system inside the new storage hoppers we have had no problems at all since day 1 of operation.”