After more than three years in the field handling highly abrasive materials, Weir Minerals Africa reports that its R55^TM premium grade elastomer pump liner is receiving positive feedback from customers. R55 is a proprietary high-tech rubber developed to operate in severe wear applications. The high grade premium black natural rubber has a low hardness suitable for pump liners, impellers and cyclone parts and its superior physical properties deliver improved cut resistance in hard, sharp particle slurries.

Rui Gomes, product manager – slurry pumps at Weir Minerals, commented: “This higher resistance to tearing makes R55 ideal for mill discharge applications, particularly in gold mining where there is a high content of silica sand which is too abrasive for metal liners.” After Weir Minerals offered the pump liners to a gold mining company in Ghana on a trial basis, the results were significant to the point that the company has since made the transition to R55 in about 90% of its pumps. He added: “Initially the idea of rubber pump liners in this application was initially greeted with a great deal of scepticism. The mine’s metal liners were lasting a maximum of one-and-a-half months before needing replacement but when we installed the R55 liners they lasted eight months. A similar case occurred at another gold operation in Westonaria, where a standard rubber compound was being used and was achieving a life of between four to five months. After introducing the R55 liners, this life was extended to nine months. Both of these demonstrate the significant benefits for clients, in terms of wear life improvement, maintenance downtime savings, cost savings and process efficiency improvements.”

Since then, this mine has been averaging nine to ten months of pump liner life across the board at three different mills, with two pumps per mill. With an improvement of more than double that which was achievable in the past, this has resulted in a huge cost saving for the mine in terms of wear life. Also critical to the operation is the fact that mill discharge is the first point of contact with the process product, so if there are constant delays to allow the liners to be replaced, this has knock-on effects in terms of productivity. Mr Gomes reports that Weir Minerals is also making excellent progress with introducing the Warman WBH range of heavy duty slurry pumps and Warman SLR medium duty slurry pumps fitted with R55 liners. “These pumps have been designed with improved wear characteristics in mind, as well as making the changing of liners and efficiency adjustment on the pump easier than ever before for the pump user. We’ve recently managed highly successful trials of these pumps at mines in South Africa and Botswana, as well as in West Africa. All trials were successful and have been converted into orders.”