BS ISO 15500‑16:2020 Road vehicles — Compressed natural gas (CNG) fuel system components.
1 Scope
This document specifies tests and requirements for the rigid fuel line in stainless steel, a compressed natural gas (CNG) fuel system component in accordance with ISO 1127 intended for use on the types of motor vehicles defined in ISO 3833.
This document is applicable to vehicles (mono-fuel, bi-fuel or dual-fuel applications) using natural gas in accordance with the ISO 15403 series.
It is not applicable to the following:
a) liquefied natural gas (LNG) fuel system components located upstream of, and including, the vaporizer;
h) fuel containers;
c) stationary gas engines;
d) container-mounting hardware;
e) electronic fuel management;
f) refuelling receptacles.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1127. Stainless steel tubes — Dimensions, tolerances and conventional masses per unit length ISO 15500-1, Road vehicles — Compressed natural gas (CNG) fuel system co,nponents — Part 1: General
requirements and definitions
ISO 15500-2:2016. Road vehicles — Compressed natural gas (CNG) fuel system components — Part 2:
Performance and general test methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 15500-1 apply.
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6.2 Hydrostatic strength Test the rigid fuel line according to the procedure for testing hydrostatic strength specified in ISO 15500-2. The test pressure shall be four times the working pressure. NOTE The higher hydrostatic test pressure for the rigid fuel line compared to the components in the other parts of the ISO 15500 series is due to the necessary provisions to cope with eventual damage or abrasions under normal operation.
6.3 Continued operation Test the rigid fuel line in accordance with the procedure for testing continued operation given in ISO 15500-2, for a total of 100 000 cycles. Following cycling testing, perform the hydrostatic test in accordance with 6.2.
6.4 Bending Test the rigid fuel line according to the following procedure and acceptance criterion. a) Select a mandrel with a diameter according to ISO 15500-2:2016, Table 1. b) Bend the rigid fuel line over this mandrel once, forming a“U” shape. c) Close the ends of the rigid fuel line and subject it to the hydrostatic test of 6.2. At the completion of the hydrostatic test, the rigid fuel line shall be tested according to the procedure for leakage testing specified in ISO 15500-2.
BS ISO 15500‑16 pdf download.