Angular contact ball bearings are used in high-speed machine tool spindles, vertical water pump motors, worm gear reducers, etc. Most of them use grease lubrication, and the temperature rise and durability of grease-lubricated bearings will be affected by the amount of grease filled. Therefore, in order to give full play to the performance of the bearing, the key is to fill it with grease in an appropriate amount according to the conditions of use. For this, we must first understand the space volume of the bearing used. Angular contact ball bearings are combined into many types by their bearing series, contact angle or cage type, etc. The following describes the space volume of commonly used bearings. Table 1 is the space volume of bearings with stamped cage for conventional use, and Table 2 is the space volume of bearings with super-strong brass cage. The contact angle codes A, B, and C in the table indicate that the nominal contact angles of the bearing are 3, 4, and 15° respectively. Table 1 Space volume of angular contact ball bearings-1 (with stamping cage).