ISO 20766-25:2022 pdf – Road vehicles — Liquefied petroleum gas (LPG) fuel system components — Part 25: Gas connections

ISO 20766-25:2022 pdf – Road vehicles — Liquefied petroleum gas (LPG) fuel system components — Part 25: Gas connections.
1 Scope This document specifies general requirements and definitions of the gas connection component of liquefied petroleum gas fuel, it is intended for use on the types of motor vehicles as defined in ISO 3833. It also provides general design principles and specifies requirements for instructions and marking. This document is applicable to vehicles (mono-fuel, bi-fuel or dual-fuel applications) using gaseous fuels in accordance with ISO 9162. It is not applicable to the following: a) fuel containers; b) stationary gas engines; c) container mounting hardware; d) electronic fuel management; e) refuelling receptacles. It is recognized that miscellaneous components not specifically addressed herein can be examined for compliance with the criteria of any applicable part of the ISO 20766 series, including testing to the appropriate functional tests. All references to pressure in this document are considered gauge pressures unless otherwise specified. This document applies to devices which have a service pressure in the range of 110 kPa (butane rich at 20 °C) and 840 kPa (propane at 20 °C), hereinafter referred to in this document. Other service pressures can be accommodated by adjusting the pressure by the appropriate factor (ratio). 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 20766-1, Road vehicles — Liquefied petroleum gas (LPG) fuel systems components — Part 1: General requirements and definitions ISO 20766-2, Road vehicles — Liquefied petroleum gas (LPG) fuel systems components — Part 2: Performance and general test methods
4 Markings Marking of the component shall provide sufficient information to allow the following to be traced: a) the manufacturer ’s or agent ’s name, trademark or symbol; b) the model designation (part number); c) the working pressure or working pressure and temperature range; d) the serial number or date code; and e) the direction of flow (when necessary for correct installation). The following additional markings are recommended: — the type of fuel; — the electrical ratings (if applicable); — the symbol of the certification agency; — the type approval number; and — a reference to this document. NOTE This information can be provided by a suitable identification code on at least one part of the component when it consists of more than one part. In the event that a component cannot accommodate all marking requirements listed in this document, the manufacturer shall include missing marking information with the packaging of the component. 5 Construction assembly The gas connections shall comply with the applicable provisions of ISO 20766-1 and ISO 20766-2, and with the tests specified in Clause 6 . Soldered or welded joints are not permitted. Soldering or welding can be permitted for connecting the individual parts of detachable couplings to the gas tube or component. Gas tubes shall only be connected by compatible fittings with regard to corrosion. Gas tubes and couplings should mate to avoid galvanic corrosion. Distributing-blocks shall be made of corrosion-resistant material. Gas tubes shall be connected by appropriate joints or fittings. Under no circumstances joints or fittings may be used whereby the tube will be damaged. The burst pressure of the joints or fittings shall be the same or higher as specified for the tube. The number of joints or fittings shall be limited to a minimum.
6.2 Hydrostatic strength Test the gas connections according to the procedure for testing hydrostatic strength specified in ISO 20766-2. The test pressure shall be 2,25 times the working pressure. 6.3 Continued operation Test the gas connections in accordance with the procedure for testing continued operation given in ISO 20766-2 for a total of 100 000 cycles. 6.4 Pull-off Test the gas tube and gas connections according to the following procedure and acceptance criteria. Secure the subject specimen in an appropriate test fixture, then statically apply a tensile load along the gas tube axis at a maximum rate of 250 N/min until the gas tube separates from the connections.