Five steps to install bearings correctly
- 2020/6/4 14:17:19
Five steps to install bearings correctly
Whether the bearing is installed correctly is related to the service life of the bearing, so everyone must pay attention to it. This article details the five steps to install the bearing correctly. Hongyuan hopes to help your work.(HONBbearing06)
①Use special tools for bearing installation and disassembly
Advanced installation tools can avoid bearing damage caused by tools and improper operation during installation. For example, when installing the bearing, the staff used the copper rod knock-in method, which is likely to cause uneven axial force on the bearing, causing the cage to deform, the rolling element is damaged, and the clearance becomes larger. The copper powder flies into the bearing cage, which may cause bearing failure.
②Check the bearings before installation
For old bearings, check the balls (pillars) for burrs, scratches, and cracks. Whether the radial clearance and axial clearance of the old bearing are qualified, generally only the radial clearance is measured. For new bearings, first check if the bearing model is correct.
③Check the matching dimensions of bearings and rotor shaft
When assembling the motor, it is also necessary to carefully check the matching size of the bearing and the rotor shaft when the bearing is installed, and the matching size of the bearing outer ring and the end cover hole.
④Control the amount of oil in the bearing and bearing room
Too much oil in the bearing and the box will cause the bearing rolling body to slip, causing the rolling body to change from rolling friction to sliding friction, and damage the bearing rolling body. Due to the excessive amount of bearing oil, the free space in the bearing box is small, and the operating temperature of the bearing will be As it rises, the grease's hysteresis decreases, the lubricating film of the rolling element becomes thinner, and the lubrication conditions are poor, which can easily cause abnormal noise of the bearing, the surface slips, and shortens the life of the bearing. Generally, there is a bearing oil chamber on the side of the motor end cover (except for motors designed as double sealed bearings). According to the speed of the motor, the amount of oil that can be injected into the bearing chamber can be implemented according to the following standards: when the motor speed is less than 1500r/min, the amount of oil is the bearing chamber 2/3 of the volume. When the speed is between 1500~3000r/min, it is 1/2 of the volume of the bearing chamber. When the speed is greater than 3000r/min, it should be less than or equal to 1/3 of the bearing volume. In the actual work process, for bearings running at high temperatures and high speeds, bearings with sealing surfaces should be used as little as possible to increase the amount of oil stored in the motor oil cover, and a grease nipple is installed to increase the operating life of motor bearings.
⑤Pay attention to ensure the insulation is intact
For bearings with an insulating design on the outer ring, care must be taken to ensure that the insulation is intact. If the bearing insulation is damaged during installation, the very thin bearing oil film will be broken down by the shaft voltage. After the oil film breaks down, not only will the rolling element's lubrication conditions be bad, but also the electric sparks generated will cause electrical corrosion on the bearing rolling body, causing rolling elements The matte surface accelerates bearing wear.