1. Type selection.
Different types of rolling bearings have different characteristics and are suitable for different service conditions of various machines. When selecting a bearing, the following factors are usually considered. Generally speaking, when bearing thrust load, choose thrust bearing and angular contact bearing. For high-speed applications, use ball bearings. When bearing large radial load, choose roller bearings. In a word, the selection personnel should choose the appropriate model from different manufacturers and a variety of bearing products.
2. Space and position occupied by the bearing.
When designing machine tools, the axis size is usually determined first, and then the rolling bearings are selected according to the shaft diameter. The small shaft is generally selected as the ball bearing, and the roller bearing is selected as the large shaft. However, when the bearing is limited in the diameter direction of the machine, needle roller bearings, ultra light and ultra light series ball bearings or roller bearings can be selected; When the bearing is limited in the axial position of the machine, you can choose narrow series or ultra narrow series ball bearings or roller bearings.
3. The size, direction and performance of the load borne by the bearing.
Load is the primary factor in bearing selection. Rolling bearings are used to bear heavy loads. Ball bearings are used to bear light or medium loads. They are made of carburized steel or bainite quenched bearings that can bear impact and vibration loads.
When subjected to pure radial load, deep groove ball bearings, cylindrical roller bearings or needle roller bearings can be selected. When bearing small pure axial load, thrust ball bearing can be selected; In case of large pure axial load, thrust roller bearings can be selected. When bearing combined radial and axial loads, angular contact ball bearings or tapered roller bearings are generally selected.
4. Bearing alignment.
If the center line of the shaft is inconsistent with the center line of the bearing seat, there is an angular error, or because the distance between the two supports of the shaft is large, and the rigidity of the shaft is small, it is easy to bend or tilt under force, then self-aligning roller bearings and outer ball bearings can be selected. If there is a slightly inclined or bent shaft, such a bearing can continue to work normally. The centering performance of bearings with different axial degrees is related to their allowable axial degrees. The larger the different axial degrees, the better the centering performance.
