Bearing fit tolerance is selected from the load condition, ring rotation, shaft and housing material, temperature, mounting method and required running clearance. The complete bearing reference and the equipment manufacturer’s tolerances should be reviewed before machining or replacing a bearing.
Why Bearing Fits Matter
An interference or clearance fit changes how the inner and outer rings are supported. An incorrect fit can contribute to ring creep, reduced internal clearance, mounting damage, heat generation or poor load distribution.
Selection Factors for Shaft and Housing Fits
- Which ring rotates relative to the load
- Radial load, axial load, shock and vibration
- Shaft and housing material, wall thickness and temperature
- Bearing type, clearance class, accuracy and mounting method
- Need for axial displacement or a locating/non-locating arrangement
Fit Review by Bearing Type
For deep groove ball bearings, review the radial load, rotating ring and internal clearance. For cylindrical roller bearings, verify the locating or non-locating function. For spherical roller bearings, confirm clearance and mounting effects. Use the bearing clearance guide together with the fit review.
Installation Checks
- Measure shaft and housing seats, shoulders and fillets.
- Confirm the correct fitting tool and apply force only to the ring being fitted.
- Check operating clearance, endplay or preload where required.
- Monitor temperature, vibration and noise after startup.
FAQ
Can I select a fit from bearing dimensions alone?
No. Dimensions do not show the load condition, ring rotation, temperature or clearance requirements.
Does an interference fit affect clearance?
Yes. Ring expansion or contraction can change the internal clearance, so the fit and clearance class must be considered together.
Request a Fit Review
Send the bearing reference, shaft and housing dimensions, material, load, speed and operating temperature through our inquiry page.