The motor itself:
1) The bearing inner and outer rings fit too tightly.
2) There are problems with the shape and position tolerance of parts, such as the coaxiality of parts such as machine base, end cover, shaft and other parts.
3) Improper selection of bearings.
4) Poor bearing lubrication or poor bearing cleaning, and there are impurities in the grease.
Shaft current. Aspects of use:
1) The unit is not installed properly, such as the motor shaft and the shaft coaxiality of the dragged device.
2) The pulley pulls too tightly.
3) The bearing maintenance is not good, the grease is insufficient or exceeds the service period, and the hair dry deteriorates.