1. There is no axial channeling of the motor, and the size between the outer cover of the bearing and the bearing jacket. When the motor is running, the rotor expands when heated, causing the bearing to heat up.

2, the bearing grease is too much, its melting out, thrown to the winding, corrosion winding.

3. Improper bearing installation or incorrect installation of pulley, external force makes the inner and outer ring of bearing loaded crooked, resulting in inflexible rotation, bearing heat damage.

4, bearing roller ball, inner and outer ring ball support serious wear and gold spalling, resulting in abnormal sound of the motor, to telephone machine sweep boring burn.

5, the motor end cover is not good, the stop is not tight, or the bearing cover is not uniform, so that the ball deviation out of the track rotation and heating.

6, the protection is not good, bearing water or dust, so that the bearing can not get good lubrication and damage