1. Incorrect installation of rolling bearing, too tight or too loose fit tolerance.

The working performance of the rolling bearing depends not only on the manufacturing accuracy of the bearing itself, but also on the dimensional accuracy, geometric tolerance and surface roughness of the matched shaft and hole, as well as the selected matching and correct installation. In general horizontal motors, the assembled rolling bearing only bears radial stress,

Inflexible rotation, heat generation during operation. If the fit between the bearing inner ring and the shaft is too loose, or the fit between the bearing outer ring and the end cover is too loose, the bearing inner ring and the shaft or the bearing outer ring rotate relative to the end cover, resulting in bearing friction, heating and overheating. In general, the tolerance zone for the inner diameter of the bearing cone as a reference part moves below the zero line in the standard. The fit between the tolerance zones of the same shaft and the fit ratio tolerance zones of the bearing cone and the general reference holes is much more important.

2. Improper selection, use and maintenance of lubricating grease, poor quality or deterioration of lubricating grease, or mixed with dust and impurities will cause bearing heating.

Too much or too little lubricating grease will also cause bearing heating, because too much lubricating grease will cause large friction between the rotating part of the bearing and the lubricating grease, while too little lubricating grease will cause dry friction and heating.

Therefore, the amount of grease must be adjusted to approximately 1/2-2/3 of the bearing housing space volume. Incorrect or deteriorated grease should be cleaned and replaced with suitable and clean grease.

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

Ball bearings are generally used at the non-shaft extension end of large and medium-sized motors. Roller bearing is used at the shaft extension end to enable the rotor to stretch out freely when heated and expanded. Due to the use of ball bearings at both ends of the small motor, the bearing outer cover and the bearing outer ring shall have proper clearance, otherwise the bearing may be heated due to excessive axial thermal extension.

In case of such phenomenon, remove the front and rear bearing caps, or add a thin paper pad between the bearing cap and the end cap to form enough clearance between the outer bearing cap and the bearing outer ring.

4. Incorrect installation of end covers or bearing covers on both sides of the motor.

If the end covers or bearing covers on both sides of the motor are not installed in parallel or the stops are not tight, the ball will rotate out of the track and generate heat.

End covers or bearing covers on both sides must be reinstalled flat and secured with evenly rotating bolts.