Why does ball mill of old style die out? We can seek reason from its configuration. The power configuration of old ball mill is the output per hour one set. After choosing the cylinder diameter of ball mill, we work out grinding media loading quantity of ball mill, and then confirm the length of ball mill cylinder according to filling rate of ball mill. And then figure out if the power that the ball mill need and the actual power of ball mill match the power of motor. Therefore, according to the ball mill actual power, choose a little larger motor, and then in response to motor power work out the grinding media loading quantity of ball mill and the length of ball mill cylinder inversely. That’s why in old ball mill, the cylinder length of ball mill of some specification is not integer. Old style ball mill has a common phenomenon that the configuration power is bigger than needed working power, which causes that the motor of ball mill can’t reach to full-load, and low operation efficiency.