Tumbling Mills Size Reduction Beyond Discovery
The ball mill differs from the tube mill by being short in length; its length, as a rule, is not far from its diameter (Fig. 2031). Feed to ball mills can be as large as to 4 cm (1 to 1a in) for very fragile materials, although the top size is generally 1 cm (a in). Most ball mills operate with a reduction ratio of 20 to 200:1.