Center drive and side drive are two common drive modes for a ball mill. Center drive grinding mill means the motor shaft extends along the axis of mill body while side drive has a motor located on the side of the mill and torque is transmitted via the large girth gear which is bolted on the flange of the mill body.

Materials are fed into the mill at a fixed flow rate along the shaft-less screw of the screw conveyor. Once inside the first compartment of the drum, the motor is activated and rotates the drum via a gearbox.

As rotation continues, steel balls inside the drum compartment are lifted up as high as centrifugal force and friction take them before falling back down on the materials.

During this process, a large crushing force acts on the materials, grinding them to finer sizes. The finely ground particles move out of the drum via a classifier. Coarse particles are returned to the mill for further grinding, which forms a so-called closed circuit.

Structure
1. Classifying liners are used to keep larger steel balls at the feed end for breaking large particles, and retain smaller steel balls at the discharge end for fine grinding. This grinding method improves efficiency.
2. True to its name, these wear-resistant liners resist severe wear.
3. Double slide shoe bearings are used to prevent the discharge end from overheating, thus ensuring operational stability and continuity.
4. Simple structure allows for ease of operation. Great adaptability enables the grinder to produce any fineness of particles in a short time.
5. Advanced diaphragm is used as a partition wall between two drum compartments. Unique grating system at the discharge end ensures only the finely ground particles can leave the drum.
6. Rubber gaskets and sealing adhesive are applied to the in-between area of slide shoe bearing housing and bearing pedestal. Strengthened seal makes certain there is oil leakage during use.