Mills – aremachines where material milled inside the rotating housing (drum) under the action of grinding media or autogenous. The mill comprises of horizontal cylindrical housing (drum) closed by end caps with hollow pins mounted in bearings. The mill is driven by a ring gear of the gear drive shaft. The drum and caps mill lined with steel plates. Their surface is wavy or stepped in order to reduce grinding media slippage. Material fed into the mill by feeder through the loading pin. Crushed material removed through discharge pin on the other side of machine.