### AMIT 135: Lesson 7 Ball Mills & Circuits – Mining .

Ball Mill Design. A survey of Australian processing plants revealed a maximum ball mill diameter of 5.24 meters and length of 8.84 meters (Morrell, 1996). Autogenous mills range up to 12 meters in diameter. The length-to-diameter ratios in the previous table are for normal applications. For primary grinding, the ratio could vary between 1:1and 1.8:1. For fine regrinding in open circuit, the ...