1 Bearing installation
1.1 bearing installation basically has the following general methods
(1) Pressing method. For small bearings with interference fit, the bearings can be press-fitted onto the shaft or housing in a mechanical or hydraulic manner.
(2) Heating method. For larger bearings or when the interference is large, the principle of thermal expansion and contraction can be used for installation. Oil bath heating or electric induction heating is generally used.
(3) Installation of tapered bore bearings. Bearings with tapered bores are always mounted with a hard fit. For cylindrical bore bearings, the radial clearance after installation is determined by the tolerance of the selected housing bore and shaft. The greater the interference between them, the smaller the radial clearance after installation. For the installation of tapered bore bearings, the interference is not the same as the bore of a cylindrical bore bearing, depending on the tolerance of the selected shaft, depending on the bearing pushing distance on the tapered journal or conical sleeve The length of time. The initial radial clearance of the bearing is gradually reduced during the push-in process, and the amount of push-in determines the degree of fit, so the initial radial clearance of the bearing must first be measured before installation. During the pushing of the bearing, the radial clearance is continuously measured until the required radial clearance reduction and the desired interference fit are achieved.
1.2 Lubrication after bearing installation
Mainly in the case of ensuring the normal operation of the bearing, the surface raceway is in direct contact with the rolling body to reduce the friction and wear inside the bearing, improve the bearing performance and prolong the service life of the bearing. The common lubrication methods are grease lubrication and oil lubrication. And solid lubrication three. In general, grease lubrication is the most widely used. Its bearing housing, sealing structure and lubrication facilities are simple, easy to maintain, and have certain ability to prevent water, gas, dust and other harmful impurities from entering the bearing interior. Oil lubrication is mainly used in heavy load, high speed, high temperature, etc. In these occasions, the lubricating oil has good fluidity and the lubrication effect is better than grease lubrication. Common oil lubrication includes oil bath lubrication, drip lubrication, splash oil lubrication, and circulating oil. Lubrication, jet lubrication, oil mist lubrication, etc. Solid lubrication is only used in certain applications where oil lubrication and grease lubrication are limited, such as high temperature and vacuum.
2 Bearing removal method
When repairing equipment, it is sometimes necessary to temporarily remove the bearing. When the bearing is damaged, it is necessary to remove the bearing and replace it with a new one. If the bearing will continue to be used after being disassembled, it is never allowed to disassemble the external force through the rolling element, otherwise the rolling element and the ferrule raceway will be crushed.
2.1 pairs of non-separable bearings
First, remove the bearing from the looser mating surface, then use the press to press the bearing out of the tight mating surface. The special tool double lever and the three rod puller can also be used to disassemble the bearing.
2.2 pairs of separate bearings
For example, a single row cylindrical roller bearing, the outer ring and the cage, the rolling body are integrated, and can be separated from the inner ring. The inner ring and the shaft are generally tightly fitted. If the inner ring is removed from the shaft, a large external force is required, and there is a possibility of damaging the inner ring hole and the surface precision of the shaft. At this time, the bearing induction heater should be used to heat the inner ring. It is convenient to disassemble in the state of thermal expansion of the inner ring. When removing a large tapered bore bearing, the oil pressure is often used to pressurize the oil in the oil hole on the tapered shaft to expand the inner ring to disassemble the tapered bore bearing.