Difference between adapter and withdrawal sleeves are explained below:
Adapter sleeves enable bearings to be mounted on smooth shafts as well as on stepped shafts. Mounting is made easier and no additional location on the shaft is required. Expensive machining of the shaft can also be avoided. Tapered seat direct on journal is however recommended when the bearings run at high speed and/or high running accuracy is required. Adapter sleeves, which generate a tight fit by driving the bearing along the sleeve.
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. For mounting bearings on stepped shafts, it is possible to use withdrawal sleeves as well.