Autogenous grinding (AG) mills are usually exposed to wear and tear during the tumbling process. To control wear and tear, which often affects production timelines, shell liners are used, as seen in the video below. The type of shell liner will determine the quality of the grind. When choosing shell liners, you need to consider several things.
Shell liners for AG mills have to fit the mills perfectly, both in size and shape. AG mills only use the ore as the grinding medium, unlike SAG mills which use steel balls together with rock particles to break down the minerals. This means AG mills are exposed to harsher conditions because the mill itself is responsible for grinding the ore into smaller, manageable sizes.
AG mills are often used to grind precious minerals, like gold and silver. A good shell liner should not cause any damage to these minerals. Otherwise, it won’t be cost-effective and it will result in losses. Rubber is usually the preferred shell liner in AG mills because it protects the mill and at the same time is gentle on the minerals.
The size and density of the minerals and other materials being ground also matter when it comes to choosing shell liners. For example, if one has to choose between metal and rubber shell liners for ag mills, the type of mineral matter, one has to consider the risks. Will the metal shell liner create imperfections in precious ore? If you will, then it is best to go for a rubber shell liner.
