ISO 9608:2022

V-belts and V-ribbed belts - Uniformity of belts - Test method for determination of centre distance variation

This document specifies a test method for determining the centre distance variation of V-belt and V‑ribbed belt drives as a criterion for the uniformity of V-belts and V-ribbed belts. This document does not apply to elastic V-ribbed belts.

Courroies trapézoïdales et courroies striées — Uniformité des courroies — Méthode d'essai permettant de déterminer les variations d'entraxe

General Information

• Status: Published
• Publication Date: 18-May-2022
• ICS: 21.220.10 - Belt drives and their components
• Technical Committee: ISO/TC 41/SC 1 - Friction
• Drafting Committee: ISO/TC 41/SC 1 - Friction
• Current Stage: 6060 - International Standard published
• Start Date: 19-May-2022
• Due Date: 15-Mar-2023
• Completion Date: 19-May-2022

Relations

• Revises: ISO 9608:1994 - V-belts - Uniformity of belts - Test method for determination of centre distance variation
• Effective Date: 26-Nov-2021

Overview

ISO 9608:2022 - V-belts and V-ribbed belts - Uniformity of belts - Test method for determination of centre distance variation defines a standardized laboratory method to measure the centre distance variation (ΔE) of V-belts and V‑ribbed belt drives. The test quantifies non-uniformities that cause force fluctuations and irregular running of belt drives. Note: the standard explicitly does not apply to elastic V-ribbed belts.

Key topics and requirements

• Measurement principle: two identical grooved pulleys, one movable under a specified measuring force (F), the other rotating at a controlled low speed.
• Belt speed limit: belt speed shall not exceed 1 m/s during measurement.
• Measured quantity: centre distance (E) between pulley axes; centre distance variation (ΔE) is the difference between the maximum and minimum centre distance measured on the standardized fixture (ΔE = Emax − Emin).
• Measurement accuracy: centre distance variation can be measured with an accuracy of 0.05 mm.
• Procedure summary:
  • Seat the belt correctly in pulley grooves and apply the specified measuring force.
  • Rotate the pulleys at least two complete revolutions to divide force equally between belt spans.
  • During a subsequent revolution record Emax and Emin and calculate ΔE.
• Test report requirements: reference to ISO 9608, centre distance variation rounded to two decimal places, belt type/profile/technical design and date of manufacture.
• Specifications for pulleys and measuring forces: given in corresponding belt standards (see Related Standards).

Practical applications

• Quality control of V-belts and V-ribbed belts during production acceptance testing.
• Comparative uniformity testing for supplier qualification and incoming inspection.
• Root-cause analysis for belt-drive vibration, noise and irregular running in manufacturing or vehicle systems.
• R&D and product development to validate belt design and manufacturing consistency.
• Maintenance and reliability engineering to assess belt condition and performance variability.

Who should use this standard

• Belt manufacturers and test laboratories
• OEMs specifying belts for industrial machinery or automotive applications
• Quality assurance teams and incoming inspection personnel
• Design engineers and maintenance teams working on belt-drive systems

Related standards

ISO 9608 references groove and belt specifications in related ISO documents for measuring pulleys and forces, including:

• ISO 1081 (vocabulary)
• ISO 1604, ISO 2790, ISO 3410, ISO 4184, ISO 5289, ISO 8419 (V-belt types)
• ISO 9981, ISO 9982 (V-ribbed belt profiles)

Using ISO 9608:2022 helps ensure consistent, repeatable measurement of belt uniformity and supports reliable, low-vibration belt-drive performance.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 9608
Third edition
2022-05
V-belts and V-ribbed belts —
Uniformity of belts — Test method
for determination of centre distance
variation
Courroies trapézoïdales et courroies striées — Uniformité des
courroies — Méthode d'essai permettant de déterminer les variations
d'entraxe
Reference number
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
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Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normatives references . 1
3 Terms and definitions . 1
4 Symbols . 1
5 Test method . 2
5.1 Measurement principle . 2
5.2 Procedure . 2
6 Results . . 2
7 Test report . 3
Bibliography . 4
iii
Foreword
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This document was prepared by Technical Committee ISO/TC 41, Pulleys and belts (including veebelts),
Subcommittee SC 1, Friction.
This third edition cancels and replaces the second edition (ISO 9608:1994), which has been technically
revised.
The main changes are
...