ISO 15500-13:2012 道路車両—圧縮天然ガス（CNG）燃料システムコンポーネント—パート13：圧力解放装置（PRD） | ページ 2

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, 2.

The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.

ISO 15500-13 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 25, Vehicles using gaseous fuels.

This second edition cancels and replaces the first edition (ISO 15500-13:2001), which has been technically revised.

ISO 15500 consists of the following parts, under the general title Road vehicles — Compressed natural gas (CNG) fuel system components:

• Part 1: General requirements and definitions
• Part 2: Performance and general test methods
• Part 3: Check valve
• Part 4: Manual valve
• Part 5: Manual cylinder valve
• Part 6: Automatic valve
• Part 7: Gas injector
• Part 8: Pressure indicator
• Part 9: Pressure regulator
• Part 10: Gas-flow adjuster
• Part 11: Gas/air mixer
• Part 12: Pressure relief valve (PRV)
• Part 13: Pressure relief device (PRD)
• Part 14: Excess flow valve
• Part 15: Gas-tight housing and ventilation hose
• Part 16: Rigid fuel line in stainless steel
• Part 17: Flexible fuel line
• Part 18: Filter
• Part 19: Fittings
• Part 20: Rigid fuel line in material other than stainless steel

Introduction

For the purposes of this part of ISO 15500, all fuel system components in contact with natural gas have been considered suitable for natural gas as defined in ISO 15403. However, it is recognized that miscellaneous components not specifically covered herein can be examined to meet the criteria of this part of ISO 15500 and tested according to the appropriate functional tests.

All references to pressure in this part of ISO 15500 are considered to be gauge pressures unless otherwise specified.

This part of ISO 15500 is based on a service pressure for natural gas used as fuel of 20 MPa [200 bar ¹ ] settled at 15 °C. Other service pressures can be accommodated by adjusting the pressure by the appropriate factor (ratio). For example, a 25 MPa (250 bar) service pressure system will require pressures to be multiplied by 1,25.

1 Scope

This part of ISO 15500 specifies tests and requirements for the pressure relief device (PRD), a compressed natural gas (CNG) fuel system component intended for use on the types of motor vehicles defined in ISO 3833.

This part of ISO 15500 is applicable to vehicles (mono-fuel, bi-fuel or dual-fuel applications) using natural gas in accordance with ISO 15403.

It is not applicable to the following:

• a) liquefied natural gas (LNG) fuel system components located upstream of, and including, the vaporizer;
• b) fuel containers;
• c) stationary gas engines;
• d) container-mounting hardware;
• e) electronic fuel management;
• f) refuelling receptacles.

2 Normative references

The following referenced documents are indispensable for the application 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.

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 15500-1 and the following apply.

Bibliography