Inner rings for needle roller bearings

Most needle roller bearings lack an inner ring and use the shaft as raceway surface. However, there may be cases where the shaft surface cannot be changed on the machine to the required hardness and/or roughness so in this case an inner ring may be used. NTN inner rings are made of high carbon chromium bearing steel blank that is heat-treated, and then finish-ground to higher precision. They are available in both metric and inch series and can also be used as bushings.

Snap rings are used for axially positioning, guiding the inner and outer rings, or the needle-roller and cage assembly in needle roller bearings. Two types are available, for either shaft and/or housing use.