RCB200 is based on high quality carbon steel. Through reasonable oil circuit design, it is coated with grease during assembly so that it can store enough grease required for a long time during operation, and can be evenly distributed on the surface of the bearing and shaft, so as to extend the service life and shorten the refueling frequency. At the same time, due to the special oil circuit system can store the dust and other foreign objects that invade the bearing during the work, so as to minimize the impact on the bearing during use. Another special feature of RCB200 is that the working surface of the bearing is treated by a special process, so that its surface is covered with a special layer of solid lubricant, which can be quickly transferred to the surface of the grinding shaft during the initial action, thereby rapidly reducing the initial friction coefficient and improving the wear resistance of the bearing.