The role of grinding medium is to produce the impact, extrusion, grinding and research in the cylinder, so that the material can meet the requirements of fineness and grading of finished products. The poor grinding medium performance will lead to poor wear resistance, high single consumption and large consumption, which seriously affects the grinding efficiency, accounting for about 30% of the consumption of vulnerable parts.

The grinding efficiency of grinding medium is mainly improved by improving its material and shape. In terms of material, low chromium white cast iron grinding ball, alloy cast iron ball with natural special alloy pig iron or scrap alloy pig iron as the main raw material, has developed rapidly because of its low price and moderate wear. 

In terms of shape, the productivity of short cylindrical, rod and cylindrical rod medium is higher than that of traditional ultrafine vertical mill, and the unit power consumption is low.