We work with many clients across the continent, and it has become very simple to see a trend in their types of questions and concerns. From these trends, you many times find that an effect of an issue can mask the real problems that are occurring. Rolling element bearings heating up are a common occurrence that can have many different causes. However, the heat, is really only an indicator and not the actual cause of the problem.
There are several causes of bearing failure. As an operator, it can be very frustrating in trying to troubleshoot a pump bearing issue when heat is the only indication that something is wrong. However, understanding how hot a pump bearing should be while it’s running is imperative.
How hot a rolling element bearing should be is based on how the pump is designed, however, all three styles of rolling element bearings have a normal in-service running temperature between 140 and 155 degrees Fahrenheit. If the bearing gets up to 180 F, that is usually considered an alarm point, and once you hit 190 F, you should shut down the pump. Some pumps have an automatic alarm, and depending on your available resources, you also may have techs that are constantly checking the bearing temperature gauges, using infrared guns, thermometers, and resistance temperature detectors.
Feeling for temperature by touching the bearing housing, is not effective, no matter how well you think you know your pump. Your skin will sense pain at 130 degrees and is not a reliable or safe gauge for determining pump temperature. The rise in temperature could or could not be happening due to an issue with the bearings. Narrowing down the cause of the heat can sometimes be a difficult task for an end-user that isn’t constantly analyzing, testing, providing maintenance and repairing pumps. However, a trained technician can analyze this issue and quickly provide a solution.
When a pump bearing is running above optimal temperature, it is most likely the root cause will ultimately found to be one or more of the following reasons:
- Misalignment between pump and driver
- Defective bearing seats on the shaft (improper tolerance/surface finish)
- Rolling element bearings overheating due to faulty mounting practices
- Improper tolerance or Class of fit selected for shaft/housing
- Insufficient or excessive lubrication
- Worn, incorrect, or insufficient bearing sealing
- Damage due to false Brinelling Electric ARC gap jumping
- Age
- Installed Operating Environment
Each one of these can cause your bearings to run higher than normal temperature and each one of these can cause your pump to finally fail if the problem isn’t addressed. Tackling potential issues as soon you are aware of them is critical. To help you, we have created informative and educational articles for each and every cause in the hope of better informing the individuals tasked with ensuring their pumps continue to run well. Of course, if you have any questions or concerns that the articles don’t cover, feel free to contact our field service team at any time to get trained expert advice on your pumps - service@ksbusa.com.
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