Bradken Linings® Composite Liners (Polywear SCL) and Bradken LMF+ Bolting (Copper State Bolting) Solution

A customer in Southern Peru, operating a 26' x 40.5' ball mill for copper processing, faced several operational challenges and approached Bradken for a solution. Previously, their mill was lined with a six-ring Cr-Mo design supplied by a competitor. The site operates two ball mills with identical feed materials and agreed to test Bradken’s solution in one mill while retaining the competitor’s Cr-Mo design in the other.

The customer sought to:

The Bradken team developed a customised solution using Bradken Linings® Polywear SCL product. To ensure the effectiveness of the design, several iterations were simulated using Discrete Element Modeling (DEM) analysis. The optimal design, featuring a double cord, double wave configuration, was selected. This innovative design reduced the number of rings from six to four and extended the shell liner length to three meters. The design minimised weight and reduced pressure on the PADs, effectively resolving the deflection issue and preventing bolt breakage. In addition to these design improvements, Bradken LMF+ Bolts were implemented to monitor and control torque, thereby enhancing the overall reliability of the installation.

The Bradken Linings® Composite Liners successfully lasted the full 18 months, with projections suggesting it could endure an additional two months. During this period, both mills processed nearly the same quantity of ore, with the Bradken-lined mill achieving a total of 23.94 million tonnes, exceeding the guaranteed throughput by 11% (21.5 million tonnes).

The installation time for the Bradken Linings® Composite Liners was 25% shorter compared to the competitor’s liner, and the number of liner pieces was reduced by 33%. This not only improved safety during installation but also reduced the exposure time for personnel during the relining process. The deflection problem was completely resolved, and no bolt breakages occurred throughout the campaign, thanks to a 31% reduction in liner weight and a 3% reduction in PAD pressure.

Furthermore, the total cost of ownership per month for the Bradken Linings® Composite Liners solution was 13% lower than the competitor’s liner solution.