Common Causes and Cures of Bearing Failure

Of the nearly 10 billion bearings being manufactured annually, approximately 0.5% – that’s 50 million – are being replaced due to damage or failure. The costs of bearing failure to production can be enormous – as much as $25K-$50K per hour, and often, the bearing itself the least expensive aspect of the failure.

According to SKF in their report Bearing Damage and Failure Analysis, 2/3 of bearing failures are due to fatigue and lubrication issues. Contamination and other issues, such as improper mounting, fit, misalignment, and overloading, make up the balance.

Preventing Bearing Failure

With bearing failures often occurring because of a mixture of issues, preventive bearing maintenance and proactive replacement at the first signs of an issue can significantly reduce premature bearing failure. Some of ways to prevent premature failure include the following:

• Lubrication Problems: Use the appropriate type and correct amount of lubricant, avoid grease loss, and follow appropriate relubrication intervals. Implement a routine lubricant analysis and vibration monitoring program.
• Fatigue: Replace bearing and/or consider redesigning to use a bearing with a greater calculated fatigue life and internal clearances. Confirm proper shaft and housing recommendations with the bearing manufacturer.
• Contamination & Corrosion: Filter lubricants, keep work areas, tools, fixtures and keep hands clean when handling. Use integrally sealed bearings or external seals in hostile environments. Make sure the correct bearing material (e.g. stainless steel) is used in corrosive environments. Follow proper bearing storage practices: in a dry room at room temperature, covered to keep clean.
• Other: Follow recommended mounting instructions and provide training on the difference between properly and improperly mounted and installed bearings. Inspect shafts and housings for run-out of shoulders and bearing seats. Note: Run-out can cause vibration of the machine and increased loads on the bearings. Eliminate or absorb external vibration that could cause the balls to move. Use lubricants containing anti-wear additives. Ground or use insulated bearings to prevent electrical currents flowing through.

Implementing a routine lubricant (oil and grease) analysis program helps to proactively assess the situation and determine the cause or source of the potential failure. Contact us today to learn how we can help.