## Ball Mill Motor Power Draw Sizing and Design Formula

The following equation is used to determine the power that wet grinding overflow ball mills should draw. For mills larger than 3.3 meters (10 feet) diameter inside liners, the top size of the balls used affects the power drawn by the mill. This is called the ball size factor S. Rod and Ball Mills by C.A. Rowland and D.M. Kjos @ Allis-Chalmers