Shaft and housing tolerances and fits
The values listed for the shaft (table 1, table 2, table 3, table 4, table 5 and table 6) and housing (table 7, table 8, table 9, table 10 and table 11) tolerances enable the character of the fit to be established:
- the upper and lower limits of Normal tolerances for the bearing bore or outside diameter deviations
- the upper and lower limits of the shaft or housing bore diameter deviations in accordance with ISO 286-2:2010
- 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
Normal tolerances for the bore and outside diameter, for which the limiting values have been calculated, are valid for all metric rolling bearings except for metric tapered roller bearings when d ≤ 30 mm or D ≤ 150 mm and thrust bearings when D ≤ 150 mm. The diameter tolerances for these bearings deviate from the Normal tolerances for other rolling bearings (table 12, table 13, table 14, table 15, table 16, table 17, table 18 and table 19).
The values for the probable interference or loose fit cover 99% of all the combinations.
When bearings with tighter dimensional tolerance than Normal are used, the bore and outside diameter tolerances are reduced. Therefore, values for an interference or loose fit need to be adjusted correspondingly. For information about calculating these limits more accurately, contact the SKF application engineering service.
The signs for clearance and interference in this catalogue are in accordance with ISO 286-1:2010. Clearance is now indicated with a “+” sign and interference with a “–” sign.