Bearing Failures And The Solutions

Bearing Failures and the Solutions

The cause of bearings to fail can usually be described by wear, fretting, corrosion, indentations, electrical pitting, smearing, cracking, or flaking.

High Temperatures on Bearings and its Lubricant

A factor that causes a lot of bearings to fail is exceeding the maximum temperature of the bearing. With today's technology high temperature metals are used to reduce this from happening but now because the metal can handle the higher temperatures the lubricant is failing and so now it is a case of finding the right lubricant for the job. Another factor which is taken into consideration with bearings is the lifetime they are needed to be used within a particular piece of machinery. For if a bearing and its lubricant can work for a limited time period at a certain temperature then it can be used because it won't matter if it fails after it is not needed. For example Tedric Harris reports in his Roller Bearing Analysis in the U.S Space Shuttle that all lubricants that they tested were reacting with the liquid oxygen that was being pumped around, the lubricants were all setting on fire or causing other types of failures. They then decided to use the liquid oxygen as the lubricant for the roller bearings, usually liquid oxygen isn't a very good lubricant as the bearing fails after so many hours but the part of the shuttle that they were working on was only needed for a couple of hours and so it was the perfect solution.

Bearing Fitting

It may sound simple but the actual fitting of the bearing can cause many problems if the bearing is not set in place properly. If the bearing is not fixed in place correctly this creates poor contact with the shaft and bearing seat which mis-aligns the bearing ring. This distortion causes unnecessary stress on the bearing and reduces its life. The bearing not being fitted properly can be a result of dirt on the shaft and so it doesn't fit properly or the wrong shaft may have been used for the wrong bearing or for the wrong purpose. Ensure you are using the correct bearing for the right purpose with the right shaft and keep it clean to avoid problems and failures.

Roller Bearing Fatigue

The fatigue on a bearing is caused by continuously loading and releasing the bearing which causes it to break. Fatigue is the general wear and tear on the bearing which becomes disfigured which then leads to problems. In essence the bearing should always outlive the piece of equipment and so if a machine does fail because of fatigue on the bearing then a different bearing more suitable to the job should be used.