Thrust roller bearing is used to bear the combined axial and radial load dominated by axial load, but the radial load shall not exceed 55% of the axial load. Compared with other thrust roller bearings, this kind of bearing has lower friction coefficient, higher speed and self-aligning performance.
1. Selection and control of tolerance of thrust roller bearing chamber: the thrust roller bearing shall rotate flexibly without blocking feeling after being pressed into the thrust roller bearing. If there is obvious inflexible rotation, it indicates that the size of the shaft is too large and the tolerance should be reduced. If there is an obvious "rusty" feeling when the thrust roller bearing is rotated by hand after being pressed into the shaft, it may be that the tolerance of the shaft is too large or the roundness of the shaft is not good. Therefore, when controlling the tolerance of shaft and thrust roller bearing chamber, it is also necessary to control the roundness. Many domestic manufacturers only control the tolerance and do not control the roundness.
2. Assembly method of thrust roller bearing: because the thrust roller bearing is a high-precision product, if it is not assembled properly, it is easy to damage the thrust roller bearing channel, resulting in the damage of the thrust roller bearing. The thrust roller bearing shall be equipped with a special mold during assembly, and can not be knocked at will. When pressing the shaft, it can only be stressed by a small ring, and when pressing a large ring, it can only be stressed by a large ring. Pneumatic or hydraulic pressure is required during assembly. During press assembly, the upper and lower dies shall be outside the horizontal state. If there is inclination, the thrust roller bearing channel will be damaged due to stress, resulting in the guide sound of the thrust roller bearing.
3. Prevention of assembly foreign matters: when the thrust roller bearing is installed on the rotor for dynamic balance, it is easy to put the iron filings generated during dynamic balance into the thrust roller bearing, so it is best to do dynamic balance before installing the thrust roller bearing. In order to facilitate assembly, some manufacturers apply some oil or grease in the thrust roller bearing chamber for lubrication effect during assembly, but it is often difficult for the operator to control the amount. If more oil or grease is accumulated in the thrust roller bearing chamber, it is easy to enter the thrust roller bearing along the shaft when the thrust roller bearing rotates. The thrust roller bearing chamber should preferably not be coated with oil or grease. If it must be coated, it should be controlled and there should be no accumulation in the thrust roller bearing chamber.
4. Prevention of paint rust: paint rust is often found in sealed motors. The sound of the motor is very good during assembly, but after it has been put in the warehouse for some time, the abnormal sound of the motor becomes very large, and there is serious rust when the thrust roller bearing is removed. In the past, many manufacturers thought it was the problem of thrust roller bearing. After our continuous publicity, the motor factory has realized that the main problem is the insulating paint. This problem is mainly because the acidic substances volatilized from the insulating paint form corrosive substances at a certain temperature and humidity, which corrodes the channel of the thrust roller bearing and leads to the damage of the thrust roller bearing. The problem can only be to select a good insulating paint and assemble it after drying and ventilation for a period of time.
The rod of 29000 bearing is an asymmetric spherical roller, which can reduce the relative sliding between the roller and the raceway in the work. In addition, the roller is long, the diameter is large, the number of rollers is large, and the load capacity is high. Oil lubrication is usually used, and grease lubrication can be used in some low-speed situations. In the design and selection, priority should be given to the selection;
80000 type thrust cylindrical roller bearing, 90000 type thrust tapered roller bearing and AXK type thrust needle roller bearing can bear unidirectional axial load. It has much greater axial load capacity than thrust ball bearing, high rigidity and small axial space.
Thrust cylindrical roller bearing and thrust tapered roller bearing are suitable for low speed occasions. The speed of thrust tapered roller bearing is slightly higher than that of thrust cylindrical roller bearing. The thrust cylindrical roller bearing is a separate bearing, which can only bear unidirectional axial load and slight impact, and can limit the axial displacement of the shaft (or shell) in one direction. Therefore, it can be used for unidirectional axial positioning. However, its bearing capacity is much greater than that of thrust ball bearing. When the roller rolls, due to the different linear speeds at both ends of the roller, the roller will inevitably slide on the ring raceway. Therefore, the limit speed of this kind of bearing is lower than that of thrust ball bearing, which is usually only suitable for low-speed operation.
The standard design of thrust cylindrical roller bearing adopts turning metal solid cage. According to the requirements of users, other types or materials of cage can also be used. The thrust tapered roller bearing can only bear the unidirectional axial load and can limit the unidirectional axial displacement of the bearing, so it can be used for unidirectional axial positioning. Compared with the thrust cylindrical roller bearing, the bearing capacity is large, the relative sliding is small, but the limit speed is low.
Thrust cylindrical roller bearings are mainly used in heavy machine tools, high-power marine gearbox, oil drilling rig, vertical motor and other machinery.