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Ten reasons why electric motors vibrate

1. Imbalance of rotor, coupler, coupling and transmission wheel (brake wheel).
2. Loose core support, loose oblique key and pin failure, and loose rotor binding will cause imbalance of the rotating part.
3. The axis of the linkage part is out of center, the center line does not coincide, and the centering is not correct.The main cause of this kind of failure is the installation process, poor and improper installation.
4. The center line of the linkage part overlaps and is consistent in the cold state, but after running for a period of time, the center line is damaged due to the deformation of the rotor fulcrum and foundation, resulting in vibration.
5. The gear and coupling connected with the motor are out of order, with poor occlusion of the gear, severe wear of the gear teeth, poor lubrication of the opposite wheel, misalignment of the coupling, wrong tooth shape and tooth spacing, excessive clearance or severe wear, all of which will cause certain vibration.
6. Defects in the motor structure itself, including ellipse of shaft neck, bending of rotating shaft, excessive or too small gap between shaft and bearing bush, and insufficient stiffness of bearing seat, foundation plate, part of foundation and even the entire motor installation foundation.
7. Installation problems: the motor is not firmly fixed between the base plate, the foot bolt is loose, and the bearing seat is loose between the base plate, etc.
8. Too large or too small clearance between shaft and bearing bush can not only cause vibration but also abnormal lubrication and temperature of bearing bush.
9. Load conduction vibration of motor drag, such as vibration of fan and water pump dragged by motor, causes motor vibration.
10. Ac motor stator wiring error, rotor winding short-circuit wound linear asynchronous motor, synchronous motor winding inter-turn short-circuit, synchronous motor excitation coil connection error, cage asynchronous motor rotor bar broken, rotor core deformation caused by stator and rotor air gap uneven, resulting in air gap flux imbalance resulting in vibration.

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