Causes of Bearing Failure
Introduced by the invention of the ball bearing more than a century ago, bearings have been a key element of machines. Bearings are designed to provide efficient operation and reduce mechanical wear, but have a limited life span due to the operating environment and operating conditions. Therefore, it is important to understand the causes of bearing failure so that effective preventive measures can be taken.
The most common causes of bearing failure can be divided into three categories: fatigue, contamination, and lubrication.
Fatigue failure occurs when the bearing is subjected to excessive load or stress, resulting in cracks and fractures. Fatigue failures are often caused by improper installation, random shocks, overloads, misalignment, out of balance rotating machines, or a lack of angular contact between the inner and outer raceways.
Contamination of the bearing is another major cause of failure. Contamination can include dirt, abrasives, and other foreign material which can interfere with bearing lubrication, cause abrasion, or cause dimensional changes. Contamination can also accelerate the speed of wear on bearing surfaces. Debris, particularly metal particles, can also block the oil supply and cause large temperature increases.
The third common cause of bearing failure comes from poor lubrication. Lubricants play an important role in preventing wear, reducing frictional losses, and limiting operating temperature. Poor lubrication can lead to an increase in friction forces and an increase in operating temperature, resulting in the formation of copper on the bearing surfaces. This copper can then act like an abrasive and accelerate the wear of the components.
In order to prevent bearing failure, it is important to inspect bearings regularly for signs of wear, check for contamination, and ensure that proper lubrication is provided. Additionally, running settings and conditions of the machinery should be closely monitored to ensure that excessive loads are not present. Immediate action should be taken when any of these causes are present, as bearing damage can cause serious damage to other components of the machinery.
In summary, bearing failure is most commonly caused by fatigue, contamination, and poor lubrication. It is important to take regular preventive measures such as inspecting the bearings, checking for contamination, and providing effective lubrication to ensure that bearing failures are minimized. By taking these proactive steps, machinery downtime and repair costs can be minimized, and machinery performance can be optimized.
