Alignment needle roller bearings
SKF alignment needle roller bearings have an outer ring with a sphered (convex) outside surface. Two polymer seating rings with a sphered (concave) inside surface are encased in a drawn sheet steel sleeve and fitted over the outer ring. This design enables the bearing to accommodate static misalignment of the shaft relative to the housing. SKF supplies alignment needle roller bearings with (fig. 1) or without (fig. 2) an inner ring.
In applications where the shaft cannot be hardened and ground, bearings with an inner ring should be used. The permissible axial displacement (→ product table) of the shaft relative to the housing is limited for bearings with an inner ring. If the permissible axial displacement provided by a standard inner ring is insufficient, it is possible to use an extended inner ring (→ Needle roller bearing inner rings).
Bearings without an inner ring are an excellent choice for compact bearing arrangements, if the shaft can be hardened and ground.