High-speed precision angular contact ball bearings are mainly used in high-speed rotating occasions with light loads. They require high precision, high speed, low temperature rise and low vibration and a certain service life. It is often used as the supporting parts of high-speed electric spindle to be installed in pairs. It is a key accessory for high-speed electric spindle of inner surface grinder. Main technical indicators: 　　 1. Bearing accuracy indicators: exceeding GB/307.1-94 P4 accuracy 2. High-speed performance indicators: dmN value 1.3~1.8x 106 /min 　　 3. Service life (average): ＞1500 h　　 high-speed precision angular contact ball Bearing service life has a lot to do with installation. Pay attention to the following: 　　1. Bearing installation should be carried out in a dust-free and clean room. The bearing should be carefully selected and the bearing spacer should be ground to maintain the inner and outer ring separation. Under the premise of the same height of the ring, the parallelism of the spacer ring should be controlled below 1um; 　　 2. The bearing should be cleaned before installation, the inner ring slopes upward when cleaning, the hand feels flexible, and there is no sense of stagnation. After drying, put in the specified amount Grease, such as oil mist lubrication, should be put in a small amount of oil mist oil; 　　3. Special tools should be used for bearing installation, with uniform force, and no beating; 　　4. Bearing storage should be clean and ventilated, free of corrosive gas, and relative humidity should not exceed 65% , Long-term storage should be regularly rust-proof.