CSA ANSI LNG 4.4:20 PDF

CSA ANSI LNG 4.4:20 PDF

Preface:

This is the first edition of CSA/ANSI LNG 4.4, Breakaway devices for liquefied natural gas (LNG) dispensing systems for natural gas vehicles (NGV).

This publication represents a Standard for safe operation, substantial and durable construction, and performance testing of breakaway device components for natural gas vehicle LNG dispensing systems, within limitations given in the scope of this Standard.

This Standard is based on proven engineering principles, research, and the combined expertise of gas utilities, manufacturers, users, and others having specialized experience.

Nothing in this Standard is to be considered in any way as indicating a measure of quality beyond compliance with the provisions it contains. It is designed to allow compliance of products which might exceed that specified in the provisions herein. In its preparation, full recognition has been given to possibilities of improvement through ingenuity of design. This Standard is subject to revision as further experience and investigation might show it is necessary and desirable.

Users of this Standard are advised that the devices/products/activities within its scope might be subject to regulation at the federal, state, provincial, or local levels. Users are strongly urged to investigate this possibility through appropriate channels. In the event of a conflict with this Standard, the federal, state, provincial, or local regulations should be followed.

CSA Group acknowledges that the development of this Standard was made possible, in part, by the financial support of Natural Resources Canada.

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 has been approved by the American National Standards Institute (ANSI) as an American National Standard.

Scope:

1.1 General

1.1.1 This Standard applies to newly manufactured LNG dispenser fuelling and vent hose emergency breakaway shutoff devices, hereinafter referred to as devices.

Notes: 1) Devices covered in this Standard are intended to be used on an LNG dispenser certified to CSA LNG 4.1 and with an LNG refuelling connector in accordance with ANSI/CAN/CSA-ISO 12617.

2) Both “one-time use” or “reusable” devices are covered in this Standard.

3) Devices can be installed “in line” or rigidly mounted at the transition from rigid piping to flexible hose at the dispenser end.

1.1.2 Devices covered by this Standard are intended to

a) minimize the escape of natural gas by automatically shutting off the flow of LNG from the dispenser and control the depressurization of the hose; and

b) minimize damage to the vehicle fuel tank and dispenser when a vehicle is driven off with the fuelling nozzle attached to the vehicle?s fuelling receptacle.

1.1.3 Devices covered by this Standard are intended for use with liquefied natural gas, a fluid in the liquid state at cryogenic temperatures that is composed predominantly of methane and that can contain minor quantities of ethane, propane, nitrogen, or other components normally found in natural gas.

1.1.4 Installation and inspection of these devices is subject to requirements in accordance with NFPA 52, CSA B108, Part 2, or other standards, as applicable, and the authority having jurisdiction (AHJ).

1.1.5 This Standard does not apply to hose breakaway devices for

a) rail locomotive dispensing systems;

b) marine vessel bunkering systems; and

c) compressed natural gas dispensers.

1.1.6 Annex A contains items that are unique to Canada.

1.2 Terminology

In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the Standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the Standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.

1.3 Measurements 1.3.1

The values given in SI units are the units of record for the purposes of this Standard. The values given in parentheses are for information and comparison only.

1.3.2 All references to pressure throughout this Standard are to be considered gauge pressures unless otherwise specified.