The boundary dimensions of SKF metric spherical plain bearings and rod ends correspond to those which have been standardized by ISO. SKF inch spherical plain bearings follow an American ANSI/ABMA standard. The appropriate standards are referenced in the sections dealing with the various bearing and rod end types.

In addition to bearings with standardized dimensions, this catalogue also includes bearings and rod ends which have been specifically designed for special applications. The boundary dimensions of these correspond only in part or not at all to the standards. Such products include radial spherical plain bearings of series GEM and rod ends of series SIR and SCF. The dimensions of these spherical plain bearings and rod ends have found general acceptance in industry so that their interchangeability is the same as for the standardized products.

Chamfer dimensions

The chamfer dimensions r1 and r2 quoted in the bearing tables are minimum values of the chamfers in the radial and axial directions for the corners of the outside diameter and side face of the outer ring, and bore and side face of the inner ring. The actual form of the chamfer is not described. In order to obtain a sufficient abutment surface even when the chamfer dimension is at a maximum, the transition between bearing seat and a shoulder in the housing or on the shaft should not be made larger than indicated by the fillet dimensions ra and rb which are given in the bearing tables (fig 1).