Shaft and housing tolerances
The values shown in tables 1a to 1e and 2a to 2e for the shaft and housing tolerances enable the character of the fit to be established
- the upper and lower limits of Normal tolerances for the bearing bore and outside diameter deviations
- the upper and lower limits of the shaft and housing bore diameter deviations in accordance with ISO 286-2:1988
- the smallest and largest values of the theoretical interference (+) or clearance (–) in the fit
- the smallest and largest values of the probable interference (+) or clearance (–) in the fit.
The Normal tolerances for the bore and outside diameter for which the limiting values have been calculated are valid for all metric rolling bearings with the exception of metric tapered roller bearings when d ≤ 30 mm and D ≤ 150 mm and for thrust bearings when D ≤ 150 mm. The diameter tolerances for these bearings deviate from the Normal tolerances for the other rolling bearings, see section Tolerances.
The values for the probable interference or clearance cover 99% of all the combinations of the theoretical interference or clearance.
When bearings of higher accuracy than Normal are used, the reduced bore and outside tolerances mean that the interference or clearance of the fits is reduced correspondingly. If, in such cases, a more accurate calculation of the limits is required it is advisable to contact the SKF application engineering service.