ball mills are commonly used in the manufacture of portland cement and finer grinding stages of mineral processing, one example being the sepro tyre drive grinding mill. industrial ball mills can be as large as 8.5 m 28 ft in diameter with a 22 mw motor, ding approximately 0.0011% of the total world's power see list of countries by electricity consumption . however, small versions of ball mills can be found in laboratories where they are used for grinding sample material for quality
the ball mill is a tumbling mill that uses steel balls as the grinding media. the length of the cylindrical shell is usually 1 1.5 times the shell diameter figure 8.11 . the feed can be dry, with less than 3% moisture to minimize ball coating, or slurry containing 20 40% water by weight.
in a continuously operating ball mill, feed material fed through the central hole one of the caps into the drum and moves therealong, being exposed by grinding media. the material grinding occurs during impact falling grinding balls and abrasion the particles between the balls.
recently, mechanical milling has proved to be an effective and simple technique without involving high temperature treatment for the production of nanocrystalline powders, with the possibility of obtaining large quantities of materials with modified properties.21 25 in this technique, starting powder particles are trapped between highly kinetic colliding balls and the inner surface of the vial, which causes repeated deformation, rewelding, and fragmentation of premixed powders resulting in
1. as the name suggests, the ball milling method consists of balls and a mill chamber. therefore over all a ball mill contains a stainless steel container and many small iron, hardened steel, silicon carbide, or tungsten carbide balls are made to rotate inside a mill drum . 2. the powder of a material is taken inside the steel container.