Features and uses roller press, also known as extrusion mill, rolling mill, is an international mid-1980s developed a new cement grinding equipment energy-saving, high alternative energy consumption, low efficiency ball mill pre-grinding system, and reduce steel consumption and noise functions for new plant construction as well as for the old plant transformation, so that the ball mill system yields increased by 30-50%, after the material extruded in cake 0.08mm fines accounted for 20-35% accounting for 65-85% less than 2mm, the internal structure of small particles due to squeezed full of many tiny cracks, grindability greatly improved. Roll surface by thermal welding, wear layer maintenance more convenient. Part of the roller press from the rack, two rolls, gearing, torque bearing, roller cover, feed, hydraulic (pressure) system, main bearing lubrication system, dry oil lubrication system, electrical system and other part of the composition .