Grinding mills are commonly used for crushing ores. A typical grinding mill comprises a large rotatable drum containing grinding media (typically steel balls or rods). The grinding mill liners are integral parts of a grinding mill. Today, liner designs and materials used in their construction have evolved to a point where virtually maintenance free liner life is ensured. Generally the mill liners are treated as the protective shield for the grinding mill surfaces, but they also play a very significant role in the energy transmission to the charge. In order to optimize the energy transmission and the surface protection, a liner should have a specified profile.

Liners are the materials which are used on the inner surface of the grinding shell to provide the necessary strength and resistance. Lining is used on all surfaces with which pulp comes in contact in order to take the wear, and thus conserve the strength and tightness of the barrel structure.

FUNCTIONS OF MILL LINERS

Regardless of the type or size of the mill in which the liners are used, mill liners perform several functions that are critical to both maintenance and the actual grinding process. The purpose for using a liner in the grinding mill can be summarized as follows:

To provide corrosion resistance (erosion from chemical action) to the shell surface

To provide abrasion resistance (erosion by friction) to the shell surface

To improve sanitation and cleaning

To improve the flowability of solids or the pulp

To provide lifting action, and to add impact and crushing

To prevent wear and associated damage to the structural members of the mill (mill shell, heads and trunnions)

To act as the final link in the transmission of energy to the tumbling load, i.e. the charge

Important Features of a Mill Liner: