Bearing Failure Mechanism
Bearing failure is one of the most common causes of mechanical failure and frequently requires the bearing to be replaced. There are many reasons resulting in bearing failure, but basically they can be classified into four general categories, namely creep failure, fatigue failure, lubrication failure and hydraulic pressure overload. The cause of each type of bearing failure must be determined in order to make the necessary corrections and prevent similar failures from occurring in the future.
Creep Failure
Creep failure occurs when a bearing is improperly mounted, causing excessive loading in the radial or axial direction. This can cause misalignment of the inner and outer race resulting in decreased availability of the race-to-race contact. This tension will increase and will eventually cause plastic deformation. This type of bearing failure is known as creep failure.
Fatigue Failure
Fatigue failure is caused by the constant cyclic loading and unloading of the bearing that occurs during its operation. This cyclic movement can cause microscopic cracks in the bearing that can eventually lead to fatigue failure.
Lubrication Failure
Lubrication failure occurs when the lubricant is unable to provide proper lubrication and cooling of the bearing. This causes an increase in the temperature and viscosity of the lubricant, decreasing its ability to lubricate the bearing properly. This will eventually result in bearing failure.
Hydraulic Overload
When excessive hydraulic pressure is applied to a bearing, it can cause the bearing to slip and transition from a bearing to a thrust bearing. This causes an overload on the bearing, resulting in a malfunction of the shaft and bearing assembly. In order to prevent this type of bearing failure, a load limit must be set to ensure that the bearing is not subjected to excess pressure.
Conclusion
Bearing failure is a common cause of mechanical failure and has many causes, including creep failure, fatigue failure, lubrication failure, and hydraulic pressure overload. It is important to determine the cause of bearing failure in order to address the issue and to prevent future problems. Proper maintenance and inspections of the bearings should be done on a regular basis in order to avoid unnecessary wear and tear in the future.
