Grease lubrication is the most commonly used lubrication method for bearings because of its convenience in use and simple maintenance. The most commonly used grease for rolling bearings is a key-based grease with mineral oil as the base oil. This grease has good adhesion and has good lubrication in a large temperature range and speed range. The applicable temperature range is -30°C~+110°C. 2. When high-speed precision bearings are lubricated with grease, the recommended grease filling amount is 15%~20% of the free space inside the bearing. 3. Grease-lubricated bearings must be run-in at the beginning of operation. After running-in, excess grease is forced into the bearing raceway, so that the grease in the bearing is evenly distributed and the lowest thermal equilibrium temperature can be guaranteed when the bearing is working normally. 4. Grease should be replenished and replaced within a certain period of time. When replenishing grease, it should be noted that greases of different types and specifications cannot be mixed, otherwise the performance of the grease will be reduced. In addition, the original grease should be cleaned when replacing the grease.