Handling Method of Bearing Overheating

Time：2020.08.20  Source：Roller Bearings Suppliers

As we well know bearing is the most important supporting component of motor.In general, when the temperature of the motor rolling bearing exceeds 95℃ and the temperature of sliding bearing exceeds 80℃, the bearing is overheated.At present, most motor manufacturers can consider embedding temperature measuring element near the bearing and then protecting the bearing by controlling circuit.

Bearing overheating is a common fault in motor operation, and the causes are various, sometimes it is difficult to accurately diagnose the specific causes.Therefore, in many cases, if the treatment is not timely, the result is often to cause more damage to the motor, the motor life is shortened, as a result of affecting the work and production.

1. Improper installation of rolling bearing, too tight or too loose fitting tolerance. 

Solution: the working performance of the rolling bearing not only depends on the manufacturing precision of the bearing itself, but also on the dimensional precision, shape and position tolerance and surface roughness of the shaft and hole fitted with it, as well as the selection and installation of the correct or not.In general horizontal motors, well-assembled rolling bearings only bear radial stress. However, if the inner ring of the bearing is too tightly fitted with the shaft, or the outer ring of the bearing is too tightly fitted with the end cover, the bearing clearance will become too small or even close to zero after assembly.Need WSBC 22224 E,click here to learn more.

If the coordination between the bearing inner ring and the shaft is too loose, or between the bearing outer ring and the end cover is too loose, the bearing inner ring and the shaft, or between the bearing outer ring and the end cover, will have relative rotation, resulting in friction and heat. The rotation will be not flexible, and heat will be generated during operation, resulting in overheating of the bearing.

2. Improper selection of grease or improper use and maintenance, poor quality or deterioration of the grease, or mixed with dust and impurities, etc. can cause bearing heating. 

Solution: too much or too little grease will also cause bearing heating, because too much grease, the bearing rotation part and grease will produce great friction, and too little grease, may appear dry friction and heating.Therefore, it is necessary to adjust the amount of grease so that it is about 1/2-2/3 of the bearing room space. Improper or deteriorated grease should be cleaned and replaced with appropriate clean grease.

3. The axial clearance between the outer bearing cover of the motor and the outer circle of the rolling bearing is too small. 

Solution: Large and medium motors generally use ball bearings at non-shaft ends.Roller bearing is adopted at the shaft extension end, which can be expanded freely when the rotor is heated.As both ends of the small motor adopt ball bearings, there should be an appropriate clearance between the outer bearing cover and the bearing outer ring, otherwise, the bearing may be heated due to too much axial thermal elongation.

4. End caps or bearing caps on both sides of the motor are not installed properly. 

Solution: if the motor on both sides of the end cover or bearing cover is not parallel or not close to the stop, it will make the ball off the track rotation and heat.Both sides of the end cover or bearing cover must be reinstalled flat and fixed with bolts rotating evenly.Click here to learn more about WSBC 22226 E.

5. Ball bearings, rollers, inner and outer rings, ball bearings are seriously worn or metal is peeled off.

Solution: The bearings should be updated at this point.

6. Poor connection with load machinery.The main reasons are as follows: poor coupling assembly, too much belt tension, not consistent with the load of the mechanical axis, too small belt wheel diameter, belt wheel is too far from the bearing, the axial or radial load suffered by too much.

Solution: Correct incorrect connections and avoid abnormal forces on the bearing. 

7. The axis is bent. 

Solution: The bearing force is no longer pure radial force, thus causing bearing heating.Try to straighten or replace a bent shaft.

Wuxi Spark Bearing Co.,Ltd welcome your inquiry anytime