This is the first edition of CSA/ANSI LNG 3.7, Road vehicles — Liquefied natural gas (LNG) fuel system components — Part 7: Pressure relief valve, which is an adoption, with North American deviations, of the identically titled ISO (International Organization for Standardization) Standard 12614-7 (first edition, 2014-07-01). At the time of publication, ISO 12614-7:2014 is available from ISO in English only. CSA Group will publish the French version when it becomes available from ISO.
For brevity, this Standard will be referred to as CSA/ANSI LNG 3.7 throughout.
The North American deviations are intended to
a) correct inaccuracies; and
b) replace references to ISO and IEC Standards with references to U.S. and CSA Group Standards, where applicable.
This Standard is intended to be used in conjunction with CSA/ANSI LNG 3.1-2018, Road vehicles — Liquefied natural gas (LNG) fuel system components — Part 1: General requirements and definitions (adopted ISO 12614-1:2014, with Canadian deviations) and CSA/ANSI LNG 3.2-2018, Road vehicles — Liquefied natural gas (LNG) fuel system components— Part 2: Performance and general test methods (adopted ISO 12614-2:2014, with Canadian deviations).
This Standard has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group. This Standard was approved by the American National Standards Institute (ANSI) as an American National Standard on June 1, 2018.
This part of ISO 12614 specifies tests and requirements for the pressure relief valve (PRV), a liquefied natural gas fuel system component intended for use on the types of motor vehicles defined in ISO 3833. This part of ISO 12614 is not applicable to the following:
a) fuel containers;
b) stationary gas engines;
c) container mounting hardware;
d) electronic fuel management;
e) refueling receptacles.
NOTE 1 It is recognized that miscellaneous components not specifically covered herein can be examined to meet the criteria of this part of ISO 12614 and tested according to the appropriate functional tests.
NOTE 2 All references to pressure in this part of ISO 12614 are to be considered gauge pressures unless otherwise specified.
NOTE 3 This part of ISO 12614 is based upon a working pressure for natural gas as a fuel of 1,6 MPa [16 bar1)]. Other working pressures can be accommodated by adjusting the pressure by the appropriate factor (ratio). For example, 2 MPa (20 bar) working pressure system will require pressures to be multiplied by 1,25.