Reasons for easy damage of bearings in three-phase motors

The main reasons for the easy damage of bearings in three-phase motors include overload operation, poor lubrication, dust pollution, improper bearing 

selection, incorrect bearing clearance code, incorrect installation method, improper matching of motor stator and rotor, excessive shaft bending or diameter 

error, and unequal lubricating grease grades.

Specific cause analysis

Overload operation: The rated load of the bearing is limited, and exceeding the rated load can lead to excessive bearing force on the shaft, reduced fatigue life, 

and possible contact fatigue tooth marks.

Poor lubrication: Poor lubrication can lead to increased bearing friction, high temperature rise, increased wear, and even contact corrosion.

Dust pollution: The mixing of dust and other particles into lubricating oil can lead to increased bearing wear and shortened lifespan.

Improper selection of bearings: The selection should be based on actual usage conditions, including factors such as load, speed, and ambient temperature. 

Improper selection can result in bearings being unable to withstand actual loads.

The bearing clearance code is incorrect: excessive or insufficient clearance can affect the operation of the motor. Excessive clearance can cause excessive 

vibration, while insufficient clearance can prevent the motor from working properly.

Incorrect installation method: Incorrect installation method can cause bearing deformation or cracking, such as directly tapping or burning the bearing.

Improper coordination of motor stator and rotor: Non concentricity or axial misalignment of the stator and rotor can cause abnormal stress on the bearings, 

affecting the operation of the motor.

Excessive shaft bending or shaft diameter error: Excessive shaft bending or shaft diameter error can affect the working clearance of the bearing, leading to 

bearing heating or sleeve running.

Incorrect brand of lubricating grease: When selecting lubricating grease, the appropriate one should be chosen according to the operating environment and 

conditions of the motor.

preventive measure

Optimize the load situation of the electric motor: avoid overloading and ensure operation within the rated load range.

Strengthen the lubrication management of bearings: select appropriate lubricating oil, ensure the thickness and quality of the oil film, and lubricate according 

to the prescribed lubrication cycle.

Regularly clean bearing contaminants: Avoid dust and other particles from entering the interior of the bearing and regularly clean the contaminants.