Bearings overheating often stems from incorrect lubrication, misalignment, or overloading—three issues that account for 70% of industrial bearing failures. Fixing these requires targeted checks: verify lubricant viscosity, confirm shaft alignment, and reduce load if operating beyond rated capacity. Below is a step-by-step guide to resolve overheating and prevent downtime.
Incorrect Lubrication
Wrong lubricant viscosity is the top cause of overheating. For example, a deep groove ball bearing (6205 series) operating at 1,500 RPM in 80°C ambient requires ISO VG 68 grease; using ISO VG 32 will cause friction buildup. Over-lubrication is equally bad: fill only 30-50% of the bearing cavity to avoid heat trapping. MS Bearings supplies pre-lubricated bearings with exact viscosity specs for common industrial applications.
Shaft Misalignment
Misalignment between the shaft and bearing housing increases friction by 20-40%, leading to rapid heat rise. Use a dial indicator to check angular and parallel misalignment: angular misalignment should be less than 0.5 degrees for radial bearings. For a 6205 bearing at 2,000 RPM, even 0.3 degrees of misalignment can cause a 15°C temperature increase. Correct alignment with shims or laser tools eliminates this issue.
Overloading and Speed Mismatch
Operating a bearing beyond its rated load or speed causes overheating. The dynamic load rating (C) of a 6205 bearing is 15.8 kN; exceeding this by 20% raises surface temperature by 25°C. Speed should not exceed the limiting speed (n) of the bearing: for 6205, the limiting speed is 12,000 RPM for grease lubrication. Adjusting load or switching to a higher load rating bearing resolves this.
For project-specific bearing troubleshooting, consult your bearing supplier. Contact MS Bearings for free technical support on selecting the right bearing for high-temperature industrial operations.
What temperature is considered abnormal for a bearing?
Normal operating temperature for most industrial bearings is 10-20°C above ambient; temperatures exceeding 80°C (176°F) indicate a problem.
