When cylindrical roller bearings are subjected to heavy axial loads, axial run-out and the size of the abutment surfaces of adjacent components are particularly important for running accuracy and even load distribution on the flange.
The inner ring flange should only be supported up to half of its height (fig. 1) so that it is not subjected to damaging alternating stresses that can result, for example from shaft deflection.
The recommended shaft abutment diameter can be obtained using
das = 0,5 (d1 + F)