Shell-Type Needle Roller Bearing

How to choose Needle roller bearings

Points to check when selecting, with the values for this product (Shell-Type 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

Thin-walled formed outer ring incorporating caged rollers. Available in open-end and closed-end types; sealed types are supplied pre-filled with grease.

FAQ

Q. What is the structure of shell-type needle roller bearings (HK, HMK, DCL, BK, BMK, DBL)?

A. They use a thin-walled formed outer ring (shell) incorporating caged rollers. Open-end and closed-end types are available.

Q. Are sealed types available for shell-type needle roller bearings, and is grease packed in them?

A. Yes, sealed types are available. Sealed types are supplied with grease packed in.

Q. What are the features and applications of shell-type needle roller bearings (HK, HMK, DCL, BK, BMK, DBL)?

A. They are thin-walled and compact. Heavy-load, inch-series, and special-size series are also available. Applications include automotive components and oscillating and rotating parts of industrial machinery.

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 15
  Found on: https://www.ntn.co.jp/japan/products/catalog/ja/2203/index.html