In current production, grinding mill speeds below 76% of the critical speed are considered low-speed grinding; speeds above 88% of the critical speed are considered high-speed grinding; and speeds above 100% are considered supercritical speed grinding.

Production practice has shown that ball mills with smooth liners, at a lower media filling rate (between 30% and 40%), and by appropriately reducing the grinding concentration, can increase the mill speed to 100%–104% of the critical speed, generally increasing the hourly throughput by 10%–30%. High-speed grinding can only be used when these conditions are met, but this will also reduce the grinding fineness; therefore, high-speed grinding should not be pursued unilaterally.