Grinding mill liners can be manufactured in various materials and designs. This depends on the type of material that will be processed in order to obtain the lowest cost per ton of processed minerals. The design of the liner must be selected according to the specific grinding applications and requirements, taking into account the wear profile and capacity of the mill.

There are other liner profiles. In most cases those special designs are not economically feasible, as they involve additional costs that do not always justify its use. However, if required, they can be manufactured.

In the case of rod mills, the design should consider the rod load through the discharge trunnion liner.  The bolt liners are made of forged steel with an oval head to prevent them from turning and loosening. These are fixed in place with a hex nut, a flat washer, and a rubber seal all these elements waterproof the cylinder holes, preventing leaks when wet grinding is used.

Installing liners in a mill is not just a matter of protecting the outer cylinder. Both the design of the liners and the materials used in their manufacture play a critical role in mill performance. If the correct material and design are used, the mill will grind effectively. On the contrary, a poor choice can lead to inefficient grinding, excess power consumption, and high maintenance costs.

Emannuel Guadimus
Technical specialist- COMESA

“We had the opportunity to solve a premature wear issue detected in a rod mill used in one of the principal Peruvian mining companies.

The processed minerals were adverse and generated a rapid wear of the mill liners; we decided to apply a method that is not very common: we used high chrome white cast iron in order to make the mill liners more abrasion resistant, increasing significantly the liner lifespan. This solution is common in ball mills but not in the case of rod mills.  The solution developed by COMESA helped increase the lifespan of mill liners from 6 to 10 months”