Sleeves permit bearings with a tapered bore to be tightly fitted on cylindrical shafts of broad diameter tolerances. In general, the bore taper of such bearings is 1:12. However, spherical roller bearings of the 240.. and 241.. series have a bore taper of 1:30. Two main types of sleeve exist:

 

  • Adapter sleeves, which generate a tight fit by driving the bearing along the sleeve. The sleeves are supplied complete with clamping nut   and   lock-washer. They comply with standard ISO 113/1.

 

  • Withdrawal sleeves, which generate a tight fit by driving the sleeve into the bore of the bearing. The latter permit easy dismounting of the bearing by simple application of the appropriate withdrawal nut. The withdrawal sleeve is used in heavy assemblies where the bearings are difficult to handle and adjust. Its removal requires a nut (sold separately) which screws onto the sleeve and presses against one face of the bearing.

 

The quality of bearing installation and fit is fundamental to the achievement of long and reliable service. The cleanliness and suitability of the lubrication are also important factors. The tolerances of the shafts that are used with sleeves are:

 

  • Diameter tolerance: quality 9 minimum
  • Form tolerance: quality 5 minimum

 

The   clamping and  withdrawal nuts  (Standard ISO  2982) are used for  axial locking of  bearings with:

  • cylindrical bare
  • tapered bore

and for  the  extraction of  a withdrawal sleeve. When used for axial attachment, they are mounted with the corresponding tab washer or locking stir up with a suitable hexagonal head bolt, thereby making a simple low-cost and low-footprint clamping device.