Inner rings for needle roller bearings

The inner ring is a ground and hardened raceway that mounts on the shaft so the needles roll on it. It is used when the shaft does not have the hardness or surface finish required for a raceway, or when there is little radial space and high load capacity is needed. It also serves to restore the raceway on worn shafts.

They are designated by three dimensions in millimeters: bore × outside diameter × width. IR 100X110X30 from SKF is a ring of 100 × 110 × 30 mm; in NSK, FIR-354015 reads 35 × 40 × 15 and FIR-404520, 40 × 45 × 20. The outside diameter of the ring is the raceway diameter, and it must match the bore diameter of the bearing or cage that sits on it.

It is common in transmissions, pumps, compressors, machine tools and lifting equipment. When choosing the ring, you must define the shaft diameter, the width of the needle roller bearing and the lubrication. If the ring width is slightly greater than the cage width, the needles can move without leaving the raceway.

We work with NSK and SKF inner rings. Send us the complete part number or the three dimensions via WhatsApp, along with the part number of the needle roller bearing or cage that goes on the ring, and we will quote it promptly.