Inner rings are made from hardened rolling bearing steel and have precision machined or ground raceways.
They are used where:
- the shaft cannot be used as a raceway with needle roller and cage assemblies, drawn cup needle roller bearings with open ends, drawn cup needle roller bearings with closed end and needle roller bearings
- needle roller bearings must be combined with wider inner rings in order to facilitate axial displacement of the shaft in relation to the housing
- optimum running surfaces are required for the seal lips.