Bearings in electric motors have a high risk of failure due to lack of lubrication or some incorrect lubrication practices. These failures are caused by reasons such as the use of incorrect lubricants, over-lubrication or contamination.
Most electric motors have anti-friction, grease-lubricated rolling bearings. Grease acts as a life enhancer for any machine because it forms an oil film that prevents rough metal-to-metal contact between rotating bearing elements. About 50% to 60% of mechanical failures are caused by bearing failures, most of which are related to poor lubrication. In this article, we will look at the main causes of failures that can cause a motor to stop running.
Improper Lubricants: There are different types of lubricants, including - those that are used only for electric motors, while other types of lubricants are specially designed for a variety of applications. Therefore, it is important to use the correct type of lubricant for the type of application. Using the wrong type of grease can cause premature bearing failure.
Overgreasing: If the grease chamber is overfilled and high pressure is applied from the grease gun, excess grease can leak into the shaft and possibly inside the motor as well. This grease can further penetrate inside the end windings of the insulation system and can cause winding insulation and bearing failures.
Lack of lubrication: Lack of lubrication can be another cause of your mechanical failure. First, insufficient grease, and second, extended relubrication intervals can create friction in your mechanical parts and can cause your machinery to not function properly.
Housing overpressure: Sometimes, when a housing is overstressed, the resulting stress can place a burden on components that were not intended to withstand that pressure. During this process, many mechanical failures are prone to occur.
Excessive grease leads to overheating: Excessive grease can cause rotating bearing elements to mix grease to push them out. This results in parasitic energy losses and increases the threat of oil separation and bearing degradation.
Grease incompatibility: Different types of grease are made with different thickeners, such as calcium and lithium. These thickeners are used in different mechanical parts. Therefore, it is important to use the same grease that is compatible with your bearing to prolong its life.