Bearing failure

We may find the following problems while identifying bearing failure:

1. Cage Damage – During use, the cage damage may occour, such as vibration, excessive speed, wear, & blockage.

2. Contamination – Contamination may be caused by the entrance of foreign objects into the bearing, such as scratches, pits, and lapping of the raceways.

3. Fatigue Failure – It is characterized by flaking or spalling of the raceway.  Fatigue failure is caused by granular weakening of the bearing steel which begins at the sub-surface and spreads to the raceway. 

4. Lubrication Failure – The original color of grease will usually turn to dark. If the grease is stiff or changed in color, it indicates lubrication failure. The grease will have an odor of burnt petroleum oil. If there is lack of oil, the lubricating oil will disappear. 

5. Misalignment – When one side of bearing is misaligned in relation to the other, the ball or roller path will run from one side of the race. This can result in high temperature and destroy of lubricant.