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Test operation check after completion of high temperature bearing installation

Update:15-11-2019
Summary:

After the installation of the high temperature bearing […]

After the installation of the high temperature bearing is completed, in order to check whether the installation is correct, a test run inspection is required. The small machine can be rotated by hand to confirm whether the rotation is smooth. The inspection items have poor operation due to foreign matter, scratches, and indentations. The installation is poor, the torque generated by the mounting is not stable, and the torque is too large due to too small clearance, installation error, and sealing friction. Wait. If there is no abnormality, the power running can be started.

The power running starts from the no-load low speed and slowly increases to the rated operation of the specified conditions. The test operation check items are whether there are abnormal sounds, changes in bearing temperature, leakage or discoloration of lubricants, and the like. If an abnormality is found, stop the operation immediately, check the machine, and remove the high temperature bearing check if necessary.

1. Prevention of assembling foreign objects: When the bearing is mounted on the rotor to make dynamic balance, it is easy to enter the iron filings generated during dynamic balancing into the bearing. Therefore, it is better to balance the load before loading the bearing. Some manufacturers have some oil or grease to lubricate the bearing chamber during assembly. However, it is often difficult for the operator to control the amount. If the oil or grease accumulates in the bearing chamber, the bearing is very rotating. It is easy to enter the inside of the high temperature bearing along the shaft. Bearing room It is good not to apply oil or grease. If it is not painted, it must be controlled not to accumulate in the bearing chamber.

2, the prevention of paint rust: the characteristics of paint rust is mostly in the sealed motor, the sound of the motor is very good when assembled, but after some time in the warehouse, the abnormal noise of the motor becomes very large, the bearing is removed Severe rust. In the past, many manufacturers thought that it was a bearing problem. After our constant publicity, the motor factory has now realized that it is mainly a problem of insulating varnish. This problem is mainly caused by the acidic substance volatilized by the insulating paint forming a corrosive substance under a certain temperature and humidity, which causes the high temperature bearing to be damaged after the bearing channel is corroded. The problem can only be achieved by selecting a good insulating varnish and venting it after drying for a while.

3. Selection and control of shaft and bearing chamber tolerance: After the bearing is pressed into the bearing, it should be flexible and unobstructed. If the obvious rotation is not flexible, it means that the size of the shaft is too large and the tolerance is lowered. If the bearing is pressed into the shaft and turned by hand, there is a clear "sand" feeling, which may be that the tolerance of the shaft is too large or the roundness of the shaft is not good. Therefore, it is necessary to control the roundness when controlling the tolerance of the shaft and the bearing chamber. At present, many domestic manufacturers only control the tolerance and do not control the roundness.

4, the assembly of the bearing: Because the bearing is a high-precision product, such as improper assembly can easily damage the bearing channel, resulting in high-temperature bearing damage. The bearing should have a special mold during assembly. It can't be beaten at will. When pressing the shaft, it can only be subjected to small force. When pressing the large circle, it can only be subjected to large force. It is required to use air pressure or hydraulic pressure during assembly. When pressing, the upper and lower touches should be outside the horizontal state. If it is tilted, the bearing channel will be damaged due to the force, which will cause the bearing to produce a sound.

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