Abutment and fillet dimensions
The dimensions of components adjacent to the bearing (shaft and housing shoulders, spacer sleeves etc.) must be such that sufficient support is provided for the bearing rings, but there must be no contact between the rotating parts of the bearing and a stationary component. Appropriate abutment and fillet dimensions are quoted for each bearing listed in the product tables.
The transition between the bearing seat and shaft or housing shoulder, may either take the form of a simple fillet according to the dimensions ra and rb in the product tables, or be relieved in the form of an undercut. Table provides suitable dimensions for the relieved fillets.
The greater the fillet radius (for the smooth form curve), the more favourable is the stress distribution in the shaft fillet area. For heavily loaded shafts, therefore, a large radius is generally required. In such cases a spacing collar should be provided between the inner ring and shaft shoulder to provide a sufficiently large support surface for the bearing ring. The side of the collar facing the shaft shoulder should be relieved so that it does not contact the shaft fillet (fig 1).
CARB toroidal roller bearings
CARB bearings can accommodate axial expansion of the shaft, within the bearing. To be sure that these axial displacements of the shaft with respect to the housing can take place it is necessary to provide space on both sides of the bearing (fig 2).
Additional information can be found in the section CARB® toroidal roller bearings.