Semi-autogenous grinding (SAG) Mill Liners

Mill liner wear is a complex process that involves two main aspects: material and liner structure. While the liner material is an important factor in liner wear, the design and structure of the liner are the most crucial factors in increasing the service life and reducing costs. Our engineering team has significantly improved the life of the liners through the study of fluid dynamics. Research has shown that, without the need to increase or change the existing materials, liner replacement can be made convenient and swift through design improvements, thereby achieving the goal of improving equipment uptime.

SAG mills exhibit characteristics of impact breakage and grinding. They contain a large number of steel balls (grinding media), lumpy materials, and slurry, and operate under harsh conditions. To protect the mill shell from direct wear caused by slurry and steel balls, the interior is fully lined with wear-resistant liners. 

These liners consist of an arc-shaped bottom plate and convex lifting ribs, cast as an integral wear-resistant liner, and fixed to the mill shell and both ends with bolts. When the grinding media and materials are continuously lifted by the lifting ribs at the connection points of the liners, the materials undergo mutual impact, smashing, and cascading, thereby achieving the self-grinding effect of the semi-autogenous mill. This grinding mechanism results in continuous wear of the liners and lifting ribs. The wear of the liners and lifting ribs not only changes their shape but also affects the height of material lift inside the mill, causing energy loss and thus reducing grinding efficiency.

The engineering team of JCC-Canhu uses several designs such as tower-like, waveform, convex, smooth, stepped, and strip-shaped liners. Liners with waveform designs help to extend the distance of cascading, intensifying the grinding effect, and thereby improving the service life of the liners.