Causes and Treatment Methods Of High Motor Bearing

The temperature of the motor bearing NSK bearings is too high, which is similar to the abnormal situation of "fever". It is a common and harmful hazard of rotating equipment. If the cause is unclear and improperly handled, it will often get twice the result with half the effort. Will cause the bearing to burn out. Therefore, to quickly determine the cause of the fault and take appropriate measures to solve it is the guarantee for the continuous safe operation of the equipment.

When the motor is running, the allowable temperature of the outer ring of the bearing should not exceed 95 ° C. If this value is exceeded, the temperature of the motor bearing is too high, also known as motor bearing heating. What is the reason for the high temperature of the motor bearing? Bearing heating is one of the most common failures of electric motors. The light will make the grease dilute and leak out, and the heavy will damage the bearing, causing economic losses to users.
 
Reason
1. The inspection and replacement are not timely, and the bearing is damaged.
2. The grease grade is incorrect or too much or too little. Generally use No. 3 lithium base grease or No. 3 compound calcium base grease, ZL3 (SY1412-75) or compound calcium base grease. After cleaning the bearing and cover, add grease to about 1/2 of the net volume.
3. The lubricating oil of the sliding bearing is not enough or there are impurities, or the oil ring is stuck and should be repaired.
4. The bearing and the end cover are too loose (outside or too tight). Spray metal on the journal when it is too loose; rework when it is too tight.
5. The bearing and the end cover are too loose (take the outer circle) or too tight. The end cover is set when it is too loose; it is reprocessed when it is too tight.
6. The end covers or bearing covers on both sides of the motor are not assembled. Reinstall it.
7. The transmission belt is too tight or too loose, the coupling is not aligned, and the vibration is large, it should be adjusted.
8. Improper bearing selection.
9. Bearing quality problems.
When the bearing temperature is high, the problem should be solved from the following aspects first. Bearing Online NSK 6320ZZS bearing 6320ZZS bearings, click here

 
1. Improper refueling quantity, too much or too little lubricating grease

The bearing box should be refueled regularly in accordance with the requirements of the work. After the bearing is lubricated, sometimes the temperature will be high, mainly due to too much lubricating.
At this time, the phenomenon is that the temperature continues to rise. After reaching a certain point (generally about 10 to 15 degrees higher than the normal operating temperature), it will remain unchanged, and then it will gradually decrease.

2. When the added grease does not meet the requirements or is contaminated

Inappropriate selection of lubricating grease, it is not easy to form a uniform lubricating film, can not reduce the internal friction and wear of the bearing, insufficient lubrication, bearing temperature rise.
When different types of grease are mixed, a chemical reaction may occur, causing the grease to deteriorate and agglomerate, reducing the lubrication effect.
The contamination of grease will also increase the temperature of the bearing, and the dust will fall into the process of adding grease, which will cause the pollution of grease, resulting in the deterioration of the grease inside the bearing box and damage the bearing lubrication, and the temperature will increase.
Therefore, suitable grease should be selected, the bearing box and bearing should be cleaned during inspection, and the oil pipeline should be checked for dredging. Different types of grease are not allowed to be mixed; if other types of grease are replaced, the original grease should be cleaned first; during operation and maintenance Grease should be added regularly, and grease should be properly stored for moisture and dust prevention measures.

3. When cooling is insufficient

Check whether the pipeline is blocked, and whether the temperature of oil inlet and return water exceeds the standard.
If the cooler is not selected properly, the cooling effect is poor, and the use requirements cannot be met, it should be replaced in time or a new cooler should be installed in parallel. The axial flow induced draft fan should also check the insulation and tightness of the core tube.

4. When there is no problem in the above aspects, check the coupling

The alignment of the coupling must meet the process standards. When aligning axial flow induced draft fans and hydraulic couplers, the problem of thermal expansion of the equipment during operation should also be considered.
The bearing box rises on the impeller side of the induced draft fan due to heat; the temperature rises during the operation of the hydraulic coupler. The bearing box expands and the bearing rises. Therefore, the motor is higher when the timing is adjusted. The size of the reserve depends on the characteristics of the equipment and Depending on the temperature parameter in operation.