Solid Needle Roller Bearing

How to choose Needle roller bearings

Points to check when selecting, with the values for this product (Solid Needle Roller Bearing).

1. 1. Select dimensions by shaft diameter and presence of inner ring

   Types without an inner ring use the shaft directly as the raceway, so the roller pitch circle diameter Fw corresponds to the applicable shaft diameter. In this case the shaft requires sufficient hardness and surface finish. If the shaft cannot serve as the raceway, select a type with an inner ring and match the shaft diameter using the bore diameter d.

2. 2. Check housing dimensions by outside diameter and width

   The outside diameter D determines the housing bore diameter, and the width C determines the axial installation space. Shell types have thin walls and allow a smaller outside diameter, but they are retained by press fit, so the housing bore tolerance and rigidity must be verified.

3. 3. Verify life and static strength with rated loads

   The basic dynamic load rating Cr is used for calculating rolling fatigue life, and the basic static load rating C0r is used for examining permanent deformation under shock loads or stationary loads. The listed Cr values range widely from 1.23 to 13200 kN, and are larger for double-row types and larger diameters.

4. 4. Choose the type suited to the application

   Select shell types for space savings and solid types for high load and high rigidity. Select self-aligning types where shaft tilt is present, combined types with thrust bearings for fixed-side positions that also carry axial load, and cam followers for applications rolling along cams or rails.

5. 5. Match rotational speed with lubrication method

   The limiting speed varies with the lubrication method, and generally oil lubrication allows higher speeds than grease lubrication. Confirm that the operating speed is below the limiting speed for each lubrication condition.

6. 6. Consider sealing and operating environment

   In environments where foreign matter or moisture may enter, selecting contact-seal types such as RS or 2RS, or grease-packed types, helps retain lubricant and reduces relubrication effort. However, the seal increases rotational resistance and imposes limits on operating temperature, so these points should be considered.

This guide was written by AI based on the listed products' documents and specification items.

About Needle roller bearings and all products

Description

The outer ring offers high rigidity and precision, and the bearing can be used without an inner ring or as an assembly with an inner ring. Dimension series are also available for heavy loads and in double-row structures.

FAQ

Q. Can the solid needle roller bearing (NK, NKS, RNA48, RNA49, RNA59, RNA69, MR) be used without an inner ring?

A. Yes, it can be used without an inner ring. Types are available that use the shaft directly as the raceway, as well as types with an inner ring.

Q. What are the structure and features of the solid needle roller bearing (NK, NKS, RNA48, RNA49, RNA59, RNA69, MR)?

A. It is a needle roller bearing with a high-rigidity, high-precision outer ring in a single-row structure. Single-row and double-row structures are available, and clearance adjustment types are also offered.

Q. What types of machines are the solid needle roller bearings (NK, NKS, RNA48, RNA49, RNA59, RNA69, MR) suited for?

A. They are used in machines where a smaller bearing housing is desired and in machine components that use the bearing without an inner ring. Dimension series for heavy loads and double-row structures are also available.

Written by AI based on the content of the source documents.

Source documents

• Catalog ニードルローラベアリング ハンドブック 80 pages Open page 14
  Found on: https://www.ntn.co.jp/japan/products/catalog/ja/2203/index.html