ISO 15500-21:2023

INTERNATIONAL ISO
STANDARD 15500-21
First edition
2023-02
Road vehicles — Compressed natural
gas (CNG) fuel system components —
Part 21:
Discharge line closures
Véhicules routiers — Composants des systèmes de combustible gaz
naturel comprimé (GNC) —
Partie 21: Fermeture des lignes de décharge
Reference number
© ISO 2023
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Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Marking . . 2
5 Construction and assembly .2
6 Tests . 2
6.1 Applicability . 2
6.2 Continued operation . 3
6.3 Internal leakage vent test . 3
6.4 Water jet protection . 3
Bibliography . 4
iii
Foreword
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This document was prepared by Technical ISO/TC 22, Road vehicles, Subcommittee SC 41, Specific
aspects for gaseous fuels.
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iv
Introduction
For the purposes of this document, all fuel system components in contact with natural gas have
been considered suitable for natural gas as defined in ISO 15403-1. However, it is recognized that
miscellaneous components not specifically covered herein can be examined to meet the criteria of this
document and tested according to the appropriate functional tests.
All references to pressure in this document are considered to be gauge pressures unless otherwise
specified.
1)
This document is based on a service pressure for natural gas used as fuel of 20 MPa [200 bar ] settled
at 15 °C. Other service pressures can be accommodated by adjusting the pressure by
...