If there are bumps, rust layers, abrasive particles, sand, dust and soil on the assembly surface of the NTN bearing and its mating parts, it is difficult to install the bearing and the assembly position is incorrect; second, these attachments form abrasives, The working surface of the bearing is easy to wear, which affects the assembly quality. Therefore, the journal, the surface of the housing hole of the bearing housing, the end face of the shoulder, and the mating surfaces of the connecting parts such as bushings, washers, and end covers should be carefully inspected before installation. If there is a rust layer, file it with a fine file, polish it with a fine emery cloth, and also remove the attachments on the bearing assembly surface and its connecting parts.
Precautions for the use of NTN bearings: Rolling bearings are precision parts, and their use must be carried out accordingly. No matter how high performance bearings are used, if they are used improperly, the expected high performance will not be obtained. Precautions concerning the use of bearings are as follows:
⑴. Keep the bearing and its surroundings clean. Even small dust invisible to the eyes can affect the bearing. Therefore, keep the surroundings clean to prevent dust from entering the bearing.
⑵. Use it carefully. A strong impact on the bearing during use will cause scars and indentations, which will cause accidents. In severe cases, it will crack or break, so be careful.
⑶. Use appropriate operating tools. Avoid replacing with existing tools, you must use appropriate tools. Such as special sleeves, presses, etc.
⑷. Pay attention to the corrosion of the bearing. When handling bearings, sweat on your hands can cause rust. Pay attention to the operation with clean hands, it is best to wear gloves as much as possible.
⑸. Before the installation preparation work is completed, do not unpack the bearing to avoid contamination.
Eric Bearing Limited provide NTN Bearing 6210ZZ.
1. Tolerance selection and control of shaft and NTN bearing chamber: NTN bearing should rotate flexibly without blocking feeling after being pressed into NTN bearing. If there is obvious inflexible rotation, it indicates that the size of the shaft is too large and the tolerance needs to be lowered. If the NTN bearing is pressed into the shaft and turned by hand, there is an obvious sense of "sand", it may be that the tolerance of the shaft is too large or the roundness of the shaft is not good. Therefore, when the tolerance of the shaft and the NTN bearing chamber is controlled, the roundness must be controlled. At present, many domestic manufacturers only control the tolerance, but do not control the roundness.
2. The assembly method of NTN bearings: Because NTN bearings are high-precision products, improper assembly can easily cause damage to the NTN bearing raceway, resulting in damage to the NTN bearing. NTN bearings should have special molds when assembling them, and they cannot be knocked at will. When pressing into the shaft, only small circles can be forced, and large circles can only be forced. When assembling, it is required to use air pressure or hydraulic pressure, and the upper and lower touch should be outside the horizontal state during press-fitting. If there is a tilt, the NTN bearing channel will be damaged due to the force, and the NTN bearing will produce noise.
3. Prevention of assembly foreign matter: When NTN bearing is installed on the rotor for dynamic balance, it is easy to enter the iron filings generated during dynamic balance into the NTN bearing, so it is best to perform dynamic balance before installing the NTN bearing. For the convenience of assembly, some manufacturers apply some oil or grease to the NTN bearing chamber for lubrication effect during assembly. However, it is often difficult for the operator to control the amount. If the oil or grease accumulates in the NTN bearing chamber a lot, the NTN bearing It is easy to enter the NTN bearing along the shaft when rotating. It is best not to apply oil or grease to the NTN bearing room.
4. Prevention of lacquer rust: The characteristic of lacquer rust is that it mostly occurs in sealed motors. The sound of the motor is very good during assembly, but after some time in the warehouse, the abnormal noise of the motor becomes very large. Remove the NTN bearing There is severe rust. In the past, many manufacturers thought it was the problem of NTN bearings. After our continuous publicity, now the motor factory has realized that the problem is mainly 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 cause damage to the NTN bearing after corrosion of the NTN bearing channel. At present, the problem can only be to choose a good insulating paint, and ventilate for a period of time after drying and assembly.
The life of NTN bearings is closely related to manufacturing, assembly, and use. Every link must be done well in order to make NTN bearings in the best operating state, thereby extending the service life of NTN bearings.