Premature aging of rolling bearings will cause equipment downtime. The experience of preventing premature aging of rolling bearings will be introduced in combination with the author's motor maintenance practices. The causes of premature aging of rolling bearings include: over-tightening, poor lubrication, misalignment of installation, strong vibration, material fatigue, pollution and corrosion.

1. Tight fit

When the inner ring of the bearing is forced into the journal, the lighter will cause a severely worn annular trajectory at the bottom of the raceway, and the heavy one will have cracks or peeling in the slideway, the outer ring and the balls. Reason: The gap between the ball and the slide is too small, the torque is increased, the friction is increased, and the bearing operating temperature is too high, which causes the bearing wear and fatigue to increase and fail.

Prevention method: Restore the radial clearance of the bearing and reduce the interference.

2. Poor lubrication

The cause is a severe lack of grease or dryness of the grease. Due to the frictional heat generated by the motor running at high speed, the bearing temperature is too high and the oxidation discoloration occurs. The bearing ball, cage, inner ring and its journal become brown or blue.

Prevention method: Determine the oil replenishment and oil change time according to the four factors of the motor's running time, ambient temperature, load conditions, and the quality of the grease. Generally, the oil should be recharged once when the motor is running for 6000 ~ 10000h; the oil should be changed once when running for 10000 ~ 20,000h. Use high-quality lithium-based grease (code ZL-2).