Typical Symptoms of Bearing Failure

Bearings are an important part of contemporary machinery and equipment. Its main function is to support the mechanical rotating body, reduce the friction coefficient during its movement, and ensure its rotation accuracy.

 

Metal bearing is the most important supporting component of the motor. Under normal circumstances, when the temperature of the rolling bearing of the motor exceeds 95 ° C and the temperature of the sliding bearing exceeds 80 ° C, the symptoms of bearing overheating will occur. At present, most motor manufacturers can consider burying temperature measuring components near the bearing, and then protect the spherical plain bearing through the control circuit. When the motor is running, overheating of the bearing is a common failure, and its causes are various. Sometimes it is difficult to accurately diagnose the specific cause. Therefore, in many cases, if the treatment is not timely, the result is often greater damage to the motor, shortening the life of the motor, which affects work and production. The following mainly explains the symptoms and solutions of bearing overheating.

 

 

Grease or oil failure or wrong selection

Too much or too little grease will also cause the metal bearing to heat up, because too much grease will cause a lot of friction between the rotating part of the bearing and the grease, and too little grease may cause dry friction and heat . Therefore, the amount of grease must be adjusted to about 1/2-2/3 of the volume of the bearing room. Unsuitable or deteriorated grease should be cleaned and replaced with suitable clean grease. The solution is to select the correct grease or oil and check the compatibility of the grease or oil.

 

 

The oil level is too high or the bearing box grease is completely filled

This will cause the lubricant to be fully stirred to produce high temperature or oil leakage. The solution is to add grease to the tank to 1/2; if the engine oil is lubricated, the oil level is slightly lower than the center of the lowermost rolling body.

Inadequate bearing clearance
The bearing clearance is not appropriate. When there is heat flow through the shaft, the inner ring will expand excessively. The solution is to check whether the clearance of the overheated bearing is within the original design range. If it is, please change to a larger clearance and change it to C3 or C3 to C4.

 

The shaft is bent
Solution: At this time, the bearing force is no longer pure radial force, so the bearing heat is caused. Try to straighten the bent shaft or replace it with a new one.

 

Roller bearings are not installed correctly, the tolerances are too tight or too loose
Solution: The working performance of the rolling bearing depends not only on the manufacturing accuracy of the bearing itself, but also on the dimensional accuracy, shape and position tolerance and surface roughness of the shaft and hole matched with it, the selected fit and the correct installation. In general horizontal motors, well-assembled rolling bearings only bear radial stress. However, if the fit between the inner ring of the bearing and the shaft is too tight, or the fit between the outer ring of the bearing and the end cover is too tight, the bearing clearance after assembly will become too small, even close to zero.

If the fit between the inner ring of the bearing and the shaft is too loose, or the fit between the outer ring of the bearing and the end cover is too loose, the inner ring of the spherical plain bearing and the shaft, or the outer ring of the bearing and the end cover, will rotate relatively, resulting in frictional heating. The rotation is not flexible, and heat will be generated during operation, causing overheating of the knuckle bearing.

 

If you have more reasons and solutions for the symptoms of bearing failure, please feel free to contact us.