Bearing Seizure: Causes, Prevention and Maintenance Guide

Bearing seizure is a critical fault where bearings get stuck on the shaft during operation, caused by severe friction between rolling elements and raceways due to abnormal stress or wear. It disrupts equipment operation and may damage related components. Below is a simplified analysis of its main causes and practical prevention measures to help reduce downtime and extend bearing life.

Main Causes of Bearing Seizure

1. Bearing Quality Defects and Wear Failure

Poor bearing quality (material defects, substandard manufacturing) and overuse beyond service life are common causes. These issues lead to premature wear of internal components (e.g., scratches on rolling elements, broken cages), which accelerates overheating and seizure, especially in motor applications.

2. Abnormal Lubrication System

Improper lubrication is a core cause of seizure, including insufficient/excessive lubrication, grease aging, and contamination. Excessive grease increases friction and temperature; insufficient lubrication causes dry friction and sintering. Improper oil seal installation also allows contaminants to enter, worsening wear and heat.

3. Installation and Assembly Errors

Incorrect installation often leads to seizure, such as improper fit clearance (too loose or tight), overheating bearings during installation, misaligned shafts, or incorrect axial gap adjustment (too small causes jamming; too large increases vibration).

4. Abnormal Load and Operating Conditions

Equipment overload, insufficient clearance for shaft thermal expansion, excessive vibration, or rotor-stator rubbing (in motors) all add extra stress to bearings, accelerating fatigue and seizure.

Practical Prevention and Maintenance Measures

1. Strict Lubrication Management

- Select lubricants suitable for the bearing model, speed, load and environment.

- Lubricate regularly in the correct dosage, avoiding insufficient or excessive lubrication.

- Keep lubricants clean and replace them regularly to prevent contamination.

- Monitor oil quality and level, handling abnormalities promptly.

2. Improve Installation Quality

- Follow installation procedures and use professional tools to avoid brute force.

- Ensure proper fit clearance between the bearing, shaft and bearing housing.

- Check and adjust shaft alignment to avoid misalignment and uneven wear.

- Control preload correctly for bearings that require it.

3. Strengthen Operation Monitoring

- Monitor bearing temperature; stop the machine if it exceeds 80℃ persistently.

- Use vibration analyzers to detect abnormal wear or misalignment.

- Pay attention to abnormal noises (squeaking, grinding) which indicate potential seizure.

- Establish a regular inspection system to resolve problems early.

4. Optimize Environmental Control

- Keep the bearing’s working environment clean.

- Install high-quality seals to prevent dust, moisture and corrosion.

- Avoid extreme temperatures and take heat dissipation/insulation measures if needed.

- Use anti-corrosion measures in harsh environments (e.g., chemical plants).

5. Standardize Maintenance and Upkeep

- Formulate and implement a regular maintenance plan.

- Replace bearings timely when they reach service life or show defects.

- Maintain complete maintenance records for traceability.

- Train operators and maintenance staff on proper procedures.

Conclusion

Bearing seizure is often caused by poor lubrication, installation errors, quality defects or abnormal conditions. By following the above prevention and maintenance measures, enterprises can reduce seizure risks, improve equipment reliability and ensure stable production.

For persistent bearing seizure issues or professional support, contact our engineering team for personalized solutions.