Bearing failures are a major cause of motor failure. Can you name some common causes of bearing failure?
Here’s a list of five common failure modes:
- Improper lubrication. Mixed grease, too little grease, or too much grease can quickly kill a bearing. Motor bearing lubrication isn’t a grunt job, it’s a job that requires expertise.
- Mechanical factors such as misalignment or a bent shaft. Ensure any critical motor has been balanced by a motor shop; check shaft runout on the other motors using a dial indicator. Perform laser alignment on all motors.
- Excess loading. Check gear boxes for lubrication and operation issues. Ensure the motor is correctly sized for the application.
- Harmonics, low power factor, or other anomalies. These can make the motor run hotter and that doesn’t help bearings.
- Unbalanced current flowing through the bearings. If you see a ground rod near a motor, suspect someone tried to fix this problem. The ground rod won’t fix it, however. Bond all metallic objects (to help provide a path around the motor rather than through it). Ensure 100% integrity of grounded conductors (i.e., return path for 277V).
