Every bearing which is designed by the manufacturer and selected by a user properly will work for its life. Any deviation in the ideal condition to be maintained for the bearing to work properly will lead to the premature failure of the bearing.
When a bearing fails it is really important to identify the real cause in order to make necessary adjustments and select an alternate bearing to prevent the failure from occurring again.
Let us now look into the various types of failure and their causes. Though each failure seems to be similar to each other. A detailed analysis is required to identify the real cause.
1. Excessive Load: A bearing which is loaded excessively, i.e. more than the rated capacity of the bearing leads to spalling in the bearings. Some other causes for the failure can be improper preloading of the bearing and tight fits on the bearings can also lead to this. Though this failure seems to look like it has occurred due to normal fatigue, the duration for this appearance will be very much shorter than the actual life time decided for the bearing. The only solution to overcome this problem would be to go in for a higher series of bearing.
2. Overheating: As the name suggests, the failure occurs due to the excessive heating of the bearing. When the bearing temperature operates around 400 Degree Fahrenheit (200 Degrees Centigrade), it tends to anneal the bearing (deprives the bearing of its hardness). Once the bearing losses its hardness, its load carrying capability also reduces because of the softness of the balls, inner cage and outer cage. The common causes for this type of failure are insufficient lubrication, presence of debris in the lubricating oil and insufficient cooling to be bearing. A good remedy for this would be continuous monitoring of the temperature of the bearing at least in critical areas.
We will look into the various other failure modes of bearings in the forth coming articles.