Essential Bearing Maintenance and Inspection Procedures

Bearing Maintenance and Inspection Procedures

Maintenance practices for bearings include disassembly for access, cleaning, inspection, and lubrication. Bearings should be cleaned with the recommended solvent, brushed clean with a soft-bristle brush, and dried with compressed air.

Critical Cleaning Safety

Never rotate the bearing while drying with compressed air. The high-speed metal-to-metal contact of the bearing rollers with the race causes heat that damages the metal surfaces.

Common Causes for Bearing Rejection

Once cleaned, the bearing is inspected. Common conditions that lead to rejection include:

• Spalling: A chipped-away portion of the hardened surface of a bearing roller or race.
• Overheating: Caused by a lack of sufficient lubrication, resulting in a bluish tint to the metal surface. The ends of the rollers may deform and flow, and the bearing cup raceway is usually discolored.
• Brinelling: Caused by excessive impact, appearing as indentations in the bearing cup raceways. Static overload or severe impact leads to vibration and premature failure.
• False Brinelling: Caused by vibration of the bearing while in a static state, which can force lubricant from between the rollers and the raceway.
• Bruising: Caused by fine particle contamination, often from a bad seal or improper maintenance, leaving a rough surface on the bearing cup.

Inspection and Handling Best Practices

When rotated, a bearing should feel smooth; roughness indicates concealed damage. The bearing should also be relatively tight with no excessive play. Contamination is a leading cause of bearing failure; abrasive substances like sand, grit, or dust can cause dents or scratches in the race or rolling elements.

Handling is of the utmost importance. Contamination, moisture, and vibration—even while the bearing is in a static state—can ruin it. Proper lubrication is a partial deterrent to negative environmental impacts.

Lubrication Recommendations

Always use the lubricant recommended by the manufacturer. Utilizing a pressure bearing packing tool or adapter is the best method to remove any contaminants that may have remained inside the bearing after cleaning.