IKO LRTZ253031 LRTZ Needle Roller Bearing Inner Ring, 25 x 30 x 31 mm

This page covers 25 IKO metric series LRTZ inner rings for general usage, made for RNA 49...UU, RNA 69...UU and GTR bearings, 10 to 60 mm bore. Choose the size from the drop-downs (outside diameter F and width B); each variant has its own dimensions, mass and assembled bearings in the Model Details.

An inner ring (inner race) is the hardened, ground raceway that the needle rollers run on. Needle roller bearings normally run directly on a heat treated, ground shaft; where the shaft cannot be made to the specified surface hardness or roughness, an inner ring is used instead. IKO inner rings are heat treated and finished by grinding to a high degree of accuracy. Rings for general usage give CN clearance when used in the matched bearings shown for each size.

LRTZ rings are the general usage rings for the RNA 49...UU and RNA 69...UU bearings (UU is the seal symbol: seals on both sides) and for GTR. Every ring on this page is matched to an RNA...UU bearing. The part number is the bore, outside diameter and width code run together.

Where this product is used

• Shaft raceway for a needle roller bearing where the shaft cannot be heat treated and ground to the specified surface hardness and roughness
• Matching inner ring for the assembled bearings listed against each size in the Model Details
• Shafts that move axially, or that run next to a seal, where a wide inner ring is needed
• A bush on a shaft with no further machining

Features

• Heat treated and finished by grinding to a high degree of accuracy
• Bore 10 to 60 mm, outside diameter 14 to 68 mm and width 14 to 46 mm across 25 sizes
• Gives CN clearance when used in the matched bearings: RNA 49...UU, RNA 69...UU and GTR
• No oil hole provided
• Can be used as a bush on a shaft with no further machining

Key specifications

Available sizes

Mass is a reference value. rs min is the minimum allowable chamfer dimension.

Selecting the right option

The drop-downs are outside diameter (F) and width (B); the ring bore d is in the Model Details. The part number is LRTZ followed by d, F and the width code run together. LRTZ rings are for the RNA 49...UU and RNA 69...UU bearings and for GTR; for the open RNA 49 and RNA 69 bearings use the LRT page.

OH at the end of the part number marks an inner ring with an oil hole. The models on this page are the standard rings with no oil hole; ask AIMS if you need an oil hole.

Fitting and use

Check the outside diameter F (the raceway size), the width B and the bore d in the Model Details against your shaft and the mating bearing. Mass is a reference value.

rs min is the minimum allowable chamfer dimension of the ring, and da is the standard mounting dimension (minimum and maximum) shown in the Model Details.

Match the ring to the bearings shown for it in the Model Details: each ring size is matched to specific bearing part numbers. If you are unsure, send AIMS the part numbers or sizes and we will confirm the fit.

Related products

Bearings these rings are matched to: RNA...UU machined type needle roller bearings without inner ring (seals on both sides). GTR is also matched to LRTZ rings; ask AIMS for GTR. For the open RNA 49, RNA 69 and the other bearings in the general usage range use the LRT inner ring page.