ISO 155:2019

INTERNATIONAL ISO
STANDARD 155
Fourth edition
2019-03
Belt drives — Pulleys — Limiting
values for adjustment of centres
Transmissions par courroies — Poulies — Limites de réglage
d'entraxe
Reference number
©
ISO 2019
© ISO 2019
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ii © ISO 2019 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 1
5 Specifications . 2
6 Factors . 3
Bibliography . 6
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 fourth edition cancels and replaces the third edition (ISO 155:1998), which has been technically
revised. The main changes compared to the previous edition are as follows:
— adding of curvilinear sections to Table 6;
— editorial clarifications of the document.
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iv © ISO 2019 – All rights reserved

INTERNATIONAL STANDARD ISO 155:2019(E)
Belt drives — Pulleys — Limiting values for adjustment
of centres
1 Scope
This document specifies the limiting values for the adjustment of centres of two transmission pulleys.
It is applicable to:
— crowned pulleys for flat belts;
— grooved pulleys for V-belts, either single, multiple or joined;
— grooved pulleys for V-ribbed belts;
— toothed pulleys for synchronous belts.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
4 Symbols
For the purpose of this document, the following symbols apply.
Symbol Definition Unit
d ± δ Limits of small flat pulley diameter mm
D ± δ Limits of large flat pulley diameter mm
e Groove pitch of a V-ribbed pulley mm
E Nominal centre distance mm
E - i Lower limit for the adjustment of centre distance mm
...