This standard specifies the boundary dimensions of two structural types of combined needle roller bearings with angular contact ball bearings (hereinafter referred to as combined bearings).
Type NKIA 0000 - the combined needle roller bearings with angular contact ball bearings (see Figure 1);
Type NKIB 0000 - the combined needle roller bearings with three-point contact ball bearings (see Figure 2).
This standard is applicable to the combined bearings installed and used in the components under large radial load and small single-direction (or double-direction) axial load as well as limited radial dimension.
