Foreword

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This document was prepared by Technical Committee ISO/TC 123, Plain bearings, Subcommittee SC 8, Calculation methods for plain bearings and their applications.

This first edition of ISO 31657-2 cancels and replaces ISO/TS 31657-2:2020 , which has been technically revised.

The main changes are as follows:

the title has been modified;
Figure 1 has been updated.

A list of all parts in the ISO 31657 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A complete listing of these bodies can be found at www.iso.org/members.html.

1 Scope

This document specifies the characteristic values for selected two-, three- and four-lobe bearings.

2 Normative references

3 Terms and definitions

4 Characteristic values for calculation of multi-lobed journal bearings

4.1 General

4.2 Two-lobe bearings

4.3 Three-lobe bearings

4.4 Four-lobe bearings

Bibliography

ISO 31657-2:2025

Plain bearings. Hydrodynamic plain journal bearings under steady-state conditions — - Part 2: Characteristic values for calculation of multilobed journal bearings

Current

Published:

16 Oct 2025

1 Scope