Whether the bearing is installed correctly is related to the service life of the bearing, so everyone must pay attention to it. Xiaohong will introduce the five steps of correctly installing the bearing in detail below, hoping to help you who are using the bearing.
Use special tools for bearing installation and disassembly
Advanced installation tools can avoid bearing damage caused by improper tools and operation during installation. For example, when installing the bearing, if the copper rod knocking method is used, it is easy to cause uneven axial force on the bearing, causing deformation of the cage, damage to the rolling element, and increase the clearance. In addition, during the knocking process of the copper rod, the copper powder flies into the bearing cage, which is easy to cause bearing failure.
Check the bearing before installation
For old bearings, it is necessary to check whether there are burrs, scratches, and cracks on the surface of the ball (column). 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 whether the bearing model is correct.
Check the matching size of the bearing and the 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 outer ring of the bearing and the end cover hole.
Control the amount of oil in the bearing and bearing chamber. Excessive oil in the bearing and the box will cause the rolling element of the bearing to slip, causing the rolling friction of the rolling element to change to sliding friction, and damage the rolling element of the bearing. Due to excessive oil in the bearing, the free space in the bearing box is small, the operating temperature of the bearing will rise, the grease density will decrease, the rolling element lubricating oil film will become thinner, and the lubrication conditions will be poor, which will easily cause abnormal noise in the bearing, surface slippage, and shorten 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 motor speed, the amount of oil that can be filled in the bearing chamber can refer to the following standards: When the motor speed is less than 1500r/min, the amount of oil added is 2/3 of the bearing chamber volume. When the speed is between 1500 and 3000r/min, it is 1/2 of the bearing chamber volume. When the speed is greater than 3000r/min, it should be less than or equal to 1/3 of the bearing volume. In actual working process, for bearings running at high temperature and high speed, bearings with sealing surfaces should be used as little as possible, the oil storage capacity of the motor oil cover should be increased, and oil nozzles should be installed to increase the operating life of the motor bearings.
Pay attention to ensure the insulation is intact
For bearings with insulation design on the outer ring, it is necessary to ensure 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 is broken down, not only the lubrication conditions of the rolling elements are poor, but also the electric sparks generated will cause electro-erosion of the bearing rolling elements, causing the rolling element surface to be uneven and accelerating the wear of the bearing.
