Feb 21, when the raymond mill is working, the grinding roll, under the action of high pressure spring and centrifugal force, rolls close up to grinding ring, its rolling pressure ratio is 1.2 times of common roller mill given an identical condition, and its output may increase 10% to 20%; please note that when the grinding roller and grinding ring.Grinding mill china. . raymond mill working principle - pew jaw crusher. raymond mill host another vulnerability is grinding roller, . get price and support online working principle of coal crushersread more /02/11 vertical roller mill training by pai this video was made by pai which introduce the working principle of vertical roller.