Seat tolerances for standard conditions

Performance and operating conditionsBearing type and arrangementBearing sizeLubricationOperating temperature and speedBearing interfacesBearing executionSealing, mounting and dismounting

The following tables provide recommendations for tolerances of shaft and housing seats. They are valid for standard applications but do not cover all details of a specific application. The information under Selecting fits and Tolerances for bearing seats and abutments should be additionally considered.

These recommendations are valid for bearings with Normal dimensional tolerances. They can also be used for bearings to P6 dimensional tolerances. The tighter P6 tolerance zone changes the resulting fit only slightly.

Recommended seat tolerances for metric bearings:

  • For solid steel shafts:
    • Radial ball bearings → table 1 (except insert bearings)
    • Radial roller bearings → table 2 (except needle roller bearings)
    • Thrust ball bearings and spherical roller thrust bearings → table 3
  • For cast iron and steel housings:

For the following bearing types, recommendations are listed in the product sections:

All ISO tolerance classes used in the tables are valid with the envelope requirement (such as H7Ⓔ), in accordance with ISO 14405-­1. For practical reasons, symbol Ⓔ is not indicated in the tables.

Bearings with a tapered bore mounted on tapered sleeves

Bearings with a tapered bore are always mounted with an interference fit for the inner ring. The fit is determined by the distance through which the inner ring is driven up on a tapered sleeve. For detailed information, refer to the information in the product sections:

For seats of bearings mounted on tapered sleeves, wider diameter tolerances are permissible. The total run-out tolerances should be the same as for bearings on cylindrical seats (→ Tolerances for bearing seats and abutments).

Suitable tolerances are listed in table 6. They are valid for moderate speeds and moderate precision requirements.
SKF logo