What is the Most Common Cause of Bearing Failure

Bearings are critical components in a wide range of machinery, from small household appliances to large industrial machines. When bearings fail, they can cause significant damage to the equipment they support, leading to costly downtime, expensive repairs, and potential safety hazards. Bearing failures occur when the bearing can no longer perform its intended function, typically due to a combination of factors that cause excessive wear or damage to the bearing raceway.

Understanding the common causes of bearing failure is crucial for maintenance engineers and operators. Identifying potential issues early makes it possible to address them before they lead to catastrophic failures. This proactive approach not only helps extend the lifespan of bearings but also maintains the overall efficiency and reliability of machinery. For more on the basics of bearing failures, click here.

Lubrication Issues

Lubrication is essential for the smooth operation of bearings. It reduces friction between rolling elements and the bearing raceway, minimizes wear, and helps dissipate heat generated by the bearing’s motion. However, lubrication problems are among the most common causes of bearing failure.

• Insufficient Lubrication: When there is not enough lubricant in the bearing, metal-to-metal contact occurs, leading to increased friction, wear, and, ultimately, bearing failure. Insufficient lubrication can be due to poor maintenance practices, incorrect lubricant selection, or simply not replenishing the lubricant at regular intervals.
• Contaminated Lubrication: Contamination of lubricant by dirt, water, or other foreign particles can severely impact bearing performance. Contaminants can cause abrasive wear, leading to the formation of scratches, pits, or grooves on the bearing surfaces. This type of damage accelerates the degradation of the bearing and can lead to premature failure.

Installation Errors

Improper installation is another major cause of bearing failures. Even the best quality bearings can fail if they are not installed correctly.

• Improper Mounting Techniques: Bearings must be installed using the correct tools and techniques. Improper mounting, such as using excessive force or not aligning the bearing properly during installation, can cause internal damage to the bearing components, leading to premature failure.
• Misalignment: Bearings are designed to operate within specific alignment tolerances. Misalignment occurs when the bearing is not properly aligned with the shaft or housing, resulting in uneven load distribution across the bearing raceway. This can cause excessive stress on the bearing, leading to overheating, increased wear, and eventual failure. Explore proper installation techniques.

Material Fatigue and Wear

Material fatigue and wear are natural processes that occur as a bearing operates over time. However, certain factors can accelerate these processes, leading to early bearing failure.

• Metal Fatigue: Metal fatigue occurs when the bearing material becomes weakened due to repeated stress cycles. Over time, microscopic cracks can form in the bearing raceway, eventually leading to spalling, where pieces of the bearing material break away. This type of damage is often irreversible and leads to the need for bearing replacement.
• Abrasive Wear: Abrasive wear happens when hard particles, such as dirt or metal debris, become trapped in the lubricant or on the bearing raceway. Rotating with these particles leaves micro-scratches on the bearing raceway. This type of wear reduces the bearing’s load-carrying capacity, leading to increased vibration, noise, and, ultimately, failure. 

Environmental Factors

The environment in which a bearing operates can significantly impact its lifespan. Severe conditions can accelerate wear and lead to premature failure.

• Temperature Extremes: Bearings are designed to operate within specific temperature ranges. Exposure to temperatures outside these ranges can cause the bearing material to expand or contract, leading to internal clearance changes, lubricant deterioration, and increased wear. High temperatures, in particular, can cause the lubricant to degrade faster, reducing its effectiveness and leading to failure.
• Corrosion: Bearings operating in environments where they are exposed to moisture, chemicals, or corrosive agents are at risk of corrosion. Corrosion can lead to pitting on the bearing raceway, which increases friction and wear. Over time, corrosion can cause the bearing to seize or fail completely.
• Indentations Caused by Metal Debris: Metal debris can become embedded in the bearing surfaces, creating indentations that lead to stress concentrations and surface fatigue. These indentations disrupt the smooth motion of the bearing, increasing wear and the likelihood of failure. Explore the environmental impact on bearings.

• Electrical Erosion: Electrical erosion, also known as electrical discharge or fluting, occurs when electric currents pass through the bearing, causing localized melting and pitting of the bearing raceway. This type of damage is common in applications where bearings are exposed to stray electrical currents, such as in electric motors.
• Corrosion by Varnish: Varnish vapour reacting with the lubricant can also lead to corrosion. If Varnish was not dried enough,  solvent within the Varnish may evaporate over time and react with the lubricant, leading to corrosion traces on the raceway. Details on corrosion by varnish.

Overloading

Bearings are designed to handle specific load capacities. The bearing can experience accelerated wear or catastrophic failure when these limits are exceeded.

• Excessive Load: Operating a bearing under loads greater than its design capacity can cause deformation of the bearing components. This deformation can lead to increased friction, heat generation, and eventual bearing failure. Improper machine design, unexpected operating conditions, or misapplication of the bearing often cause overloading.
• Vibration and Shock Loads: Bearings subjected to excessive vibration or shock loads can experience premature failure. These forces can cause brinelling, where indentations form on the bearing raceways, leading to increased noise, vibration, and wear. Vibration can also cause the lubricant to break down, reducing its effectiveness and leading to failure. Learn more about the effects of overloading.

To prevent bearing failures and extend their service life, following best practices in lubrication, installation, and maintenance is essential.

• Optimal Lubrication: Ensuring that bearings are adequately lubricated with the correct type and amount of lubricant is crucial. Regularly monitor the condition of the lubricant and replace it as needed to prevent contamination and degradation.
• Proper Installation: Use the correct tools and techniques when installing bearings. Ensure that the bearing is properly aligned and that mounting forces are evenly distributed. Avoid using excessive force, which can damage the bearing components.
• Regular Monitoring: Implement regular maintenance checks to monitor bearing conditions. Use modern monitoring tools like vibration analysis and thermoprobe to detect early signs of wear and failure. This proactive approach allows for timely maintenance and can prevent catastrophic failures. Understand vibration and shock loads.

Proactive maintenance and monitoring are key to preventing bearing failures. Regular inspections, along with the use of advanced monitoring tools, can help detect potential issues before they lead to significant damage.

• Vibration Analysis: Vibration analysis can detect early signs of bearing wear or misalignment. Maintenance teams can identify issues before they escalate by monitoring vibration levels, allowing for timely intervention.
• Thermoprobe: Thermoprobe can identify hot spots in bearings, indicating potential lubrication issues or excessive friction. Early detection of these problems can prevent overheating and subsequent bearing failure.
• Routine Inspections: Regularly inspect bearings for signs of wear, corrosion, or contamination. Address any issues promptly to prevent further damage and extend bearing life.

TPI Bearings are known for their high quality and adherence to strict environmental standards. Their products are designed to meet the demanding requirements of various applications while offering cost-effective solutions without compromising on performance.

• Product Quality and Environmental Standards: TPI Bearings are manufactured to the highest standards of quality, ensuring reliable performance in a wide range of applications. The company is also committed to environmental sustainability, adhering to strict regulations and using eco-friendly materials and processes.
• Cost-Effective Solutions: TPI Bearings offer a balance of affordability and quality, making them a cost-effective choice for many industries. Their products are designed to provide long-lasting performance, reducing the need for frequent replacements and minimizing downtime.
• Made in Taiwan: TPI Bearings are proudly made in Taiwan, a country known for its precision engineering and manufacturing excellence. The company’s commitment to quality and innovation is reflected in every product they produce.
• Rich Bearing Application Experience: With extensive experience in various bearing applications, TPI Bearings has the expertise to provide tailored solutions for a wide range of industries. Whether you need bearings for automotive, industrial, or precision applications, TPI has the knowledge and products to meet your needs.

Understanding the common causes of bearing failure and taking proactive steps to prevent them can save your business from costly downtime and repairs. For more detailed information and to explore TPI’s range of high-quality bearings, visit the TPI Home Page. With TPI Bearings, you can trust that your machinery will operate smoothly and efficiently, backed by a company committed to quality and customer satisfaction.