1. Bearing performance and material Because the rings and rolling elements of the rolling bearing are subject to repeated high contact pressure and rolling contact, and the bearing retainer is subject to tensile or compressive force and sliding contact, there are certain requirements for the material properties of each part of the bearing. . The performance of bearing rings and rolling elements requires high rolling fatigue strength, high hardness and good friction resistance. Bearing cage materials require high mechanical strength and good stability. In addition, the bearing material must have good machinability. For bearings in special environments and uses, it is also required to have good high temperature resistance, impact resistance, corrosion resistance and other properties. Bearing rings and rolling element materials usually use high carbon chromium bearing steel. Most of the bearings use SUJ2 in the JIS steel grade, and large bearings use SUJ3. In addition to the above steel types, depending on the application, high-speed steel with excellent heat resistance and stainless steel with good corrosion resistance are also used. The material of the bearing stamping cage is generally low carbon steel. Depending on the application, brass plates and stainless steel plates can also be used. The material for cutting the cage is high-strength brass, carbon steel, and synthetic resin is also available. 2. Lubrication of bearings The lubrication methods of bearings are divided into grease lubrication and oil lubrication. In order to make the bearing function well, it is necessary to select a lubrication method suitable for the conditions of use and the purpose of use. In terms of lubricating performance, lubricating oil has more advantages than grease. Grease can relatively simplify the structure around the bearing. Choose lubricating oil or grease according to the actual situation. (1), reduce friction and wear. In the mutual contact parts of the rings, rolling elements and cages that constitute the bearing, metal contact is prevented, and friction and wear are reduced. (2), prolong the fatigue life. The rolling fatigue life of the bearing is extended when the rolling contact surface is well lubricated during rotation. Conversely, if the oil viscosity is low and the lubricating oil film thickness is not good, it will be shortened. (3), discharge friction heat, cooling. The oil circulation method, etc., can use oil to discharge heat generated by friction or heat from the outside, and cool it. Prevent the bearing from overheating and prevent the aging of the lubricating oil itself. (4) The effect of preventing foreign matter from invading the bearing, or preventing rust and corrosion.