There are many types of ore grinding machine in the mining industry, the classifications are as follows:
(1) According to the grinding medium
① Ball mill – the medium is metal ball ( steel ball or cast iron ball ).
② Rod mill – the medium is steel rod.
③ Pebble mill – the medium is pebble.
④ Autogenous mill – the medium is ore, or steel ball if needed.
(2) According to discharging mode
① Overflow discharging machine – the ore pulp is discharged from the hollow shaft on the discharging side. See figure-1(a).
② Grate ball mill – the materials are discharged from the grate gap that installed on the discharging side. See figure-1(b).
③ Peripheral discharge type milling machine – the materials are discharged around barrel. See figure-1(d).
(3) According to the barrel shape
① Short barrel grinding machine. L/D ≤ (1.0-1.5) (L = grinding machine length，D = grinding machine diameter)
② Long barrel grinding machine. L/D ≤ 1.5. L/D is 5-6, it is called tube mill. The inside is divided into several chamber, also called multi-chamber grinding machine, it is used in cement industry. See figure-1(e), (f).
③ Conical grinding machine. See figure-1(c).