Cylindrical roller bearings are separable, easy to mount and dismount especially more outstanding when they are used on bearings requiring interference fit between inner and outer rings with the shaft and housing. Cylindrical roller bearing is contacted with the fair line between the rollers and the raceway, which is of elimination of edge stress. Comparing with the ball bearings, with same boundary dimensions, cylindrical roller bearings have larger radial carrying capacity. Comparing with structure, this type of bearing is more suitable for high speed rotation.