Bearing friction is mainly caused by the rolling friction and sliding friction between the rolling element and the raceway of the ferrule; the sliding friction between the cage and the guide surface of the rolling element and the ferrule (the sliding friction between the rolling elements when there is no cage) ; The friction between the roller end face and the ferrule side face; the viscous resistance of the lubricant; the sliding friction of the sealing device, etc. The size depends on the type, size, load, speed, lubrication and sealing of the bearing Factors. In the need of low friction torque instruments and machinery, usually the choice of deep groove ball bearings, cylindrical roller bearings and self-aligning ball bearings to withstand radial load; use single row thrust ball bearings to bear the load, if the joint load can be Selection of angular contact ball bearings, load angle and contact angle is basically the same, the smallest friction torque can be obtained; if the two corners of the gap is too large, the choice of radial and thrust bearing assembly approach to solve. Selection of low friction torque bearings, structural design should avoid the use of contact-type seal. At the same time, low friction torque bearing lubrication methods should be used drip lubrication, oil mist lubrication and oil and gas lubrication.
