For a century, Weir Minerals' Linatex® Premium Rubber has been protecting capital equipment from abrasion and corrosion and keeping operators safe. 

First patented in 1923, the inventor of Linatex, Bernard Wilkinson Sr, observed that conventional rubber processing - with its high shear mastication and high-temperature curing - destroyed the molecular structure of natural rubber, diminishing its original mechanical strength. He developed a ‘liquid phase low temperature vulcanisation' process that retained natural rubber's desirable properties - its toughness, resilience and abrasion resistance. 

The Linatex rubber formula and process has remained unchanged for 100 years and, today, it's utilised at all stages of the mining process, from pit to tailings. 

Weir Minerals commitment to its customers is simple: it aims to provide best-in-field performance at the lowest cost of ownership. It does this by using the best-quality natural rubber and by processing it with leading-edge technology.

Cost of wear

The charts illustrate typical performance/replacement timelines for Linatex® Premium Rubber compared to other rubbers. 

Although the initial upfront costs of using Linatex® Premium Rubber may be slightly higher, its superior wear performance results in a lower total cost of ownership. 

 Premium Rubber versus Substitute Products in Wet Abrasion Environment

Moreover, Linatex® Premium Rubber significantly outperforms its competitors in more aggressive wear environments, meaning that this is where miners get the greatest return on investment.  

The Linatex® Advantage Over Normal Rubber

Technology benefits

The making of natural rubber from natural latex involves two distinct operations: the compounding and coagulation of the latex into uncured rubber crepe and the pressing and curing of the uncured rubber into finished sheets. 

For decades these processes have been accomplished by processing individual batches of product that, even with the utmost care, increases the potential for batch-to-batch variation. 

The Weir Minerals' modern, state-of-the-art rubber processing facility in Malaysia, the sole producer of Linatex® rubber in the world, demonstrates a 100% commitment to the preservation of superior natural rubber properties. High-technology automated processes allow improvements in volume and output, while continuous processing delivers better control, higher tolerances and improved consistency over batch processing.

Demonstrable, measurable wear life improvements

Freeport-McMoRan (trading as PT Freeport Indonesia) sought Weir Minerals expertise to help reduce the high wear rate of its SAG mill discharge box dart valve seat liners at its copper-gold operation in the Grasberg minerals district in Indonesia. 

The incumbent liners were lasting 3 months, but, since the SAG mill maintenance interval was scheduled for every 6 months, it was forcing early shutdowns. Therefore, PT-FI wanted to match the wear life of the dart valve seats with the 6 month maintenance intervals. 

The Weir Minerals solution was to introduce superior Linatex® rubber material and mould the product into the existing dart valve seat configuration. The team also re-engineered and introduced a taper shape to give extra impact absorption for the rubber lined product.

Bottom of dart valve seat with Linatex® rubber lining - ready for installation

As a result, the Linatex® rubber lined product now lasts up to 7 months, which allows PT-FI to operate its SAG mills without the need for shutdown in between the 6 month scheduled intervals, thereby eliminating expensive unplanned mill downtime. When the mills stop turning, production grinds to a halt; and with the current copper price, this represents millions of dollars in lost production for each mill shutdown.

According to Yacobus Buntulobo, PT-FI's Maintenance Planning Superintendent, the project testified to both Weir Minerals' technical knowhow and its servicing and support capabilities.  

‘Weir Minerals is seen as the wear experts when looking at challenges at a client's operation site,' he said.

‘It was impressive to get a product specialist sent on-site to attend to the issues and then handle them seriously and professionally.'

The complete rubber solution 

Weir Minerals is both a supplier and applicator of the Linatex® Premium Rubber, and it takes full responsibility for all facets of the lining project. With over 100 years' experience in the production, testing and application of rubber products in many industries, it has facilities in most major mining regions of the world and is supported by an extensive list of distributors. 

Miners know that when they purchase a Linatex® Premium Rubber product, expert service and support will be close by. 

Learn more about what Linatex® Premium Rubber can do for you at www.linatex100.weir.