Centering performance of bearing

When the center line of the shaft does not coincide with the center line of the bearing seat and has angle error, or when it is bent or tilted due to the force of the shaft, the axis of the inner and outer rings of the bearing will be inclined. At this time, the ball bearing or the roller bearing with certain centering performance shall be used. This kind of bearing can still work normally when the axis of inner and outer ring has little relative deflection.
Cylindrical roller bearing and needle bearing are most sensitive to the deflection of the bearing, and the bearing capacity of these bearings in the skew state may be lower than that of the ball bearing. Therefore, when the stiffness of the shaft and the bearing bearing bore are low, it is necessary to avoid using such bearings as possible.
Installation and removal of bearings
It is easy to install and dismantle, and it is also a factor to be considered when selecting bearing type. When bearing parts must be installed and removed along the axial direction without split surface of bearing pedestal, the separable bearing (such as N0000, na0000, 30000, etc.) with internal and external rings shall be preferred. When the bearing is installed on the long shaft, in order to facilitate the removal, the bearing with cone hole of 1:12 in the inner ring hole (used for installation on the fixing bush) can be selected.
According to the requirements of speed on bearings, the following points can be determined:
1) Compared with roller bearing, ball bearing has higher limit speed, so ball bearing should be preferred in high speed;
2) Under the same condition of inner diameter, the smaller the outer diameter, the lighter the rolling body is, the smaller the centrifugal inertia force applied to the outer ring raceway when the rolling body is running, so it is more suitable for working at higher speed. Therefore, in high speed, it is advisable to select ultra light, extra light and light series bearings. Heavy and extra heavy series bearings are only used in low speed and heavy load occasions. If a light series bearing is used and the bearing capacity cannot meet the requirements, it may be considered to adopt a wide range of bearings or two light series bearings and install them together for use.
3) The material and structure of the cage have great influence on the bearing speed. The solid cage allows a higher speed than the ram cage.
4) The ultimate speed of thrust bearing is very low. When the working speed is high, if the axial load is not very large, angular contact ball bearing can be used to bear the pure axial force.
5) If the working speed is slightly higher than the limit speed specified in the sample, the bearing tolerance level can be improved, or the radial clearance of the bearing can be increased appropriately, the circular lubrication or oil mist lubrication shall be selected, and the cooling of circulating oil shall be strengthened to improve the bearing telling performance. If the working speed exceeds the limit speed, special high-speed rolling bearing shall be selected.