ISO 16486-4:2022 pdf download – Plastics piping systems for the supply of gaseous fuels — Unplasticized polyamide (PA-U) piping systems with fusion jointing and mechanical jointing — Part 4: Valves.
5 Material 5.1 Compound for valve body 5.1.1 Compound The compound from which the valve body with spigot or electrofusion socket is made shall be in accordance with ISO 16486-1. The PA-U components of the valve shall be made from virgin material conforming to ISO 16486-1. 5.1.2 Fusion compatibility Components made from PA-U 11 shall be heat fusion jointed only to components made from PA-U 11. Components made from PA-U 12 shall be heat fusion jointed only to components made from PA-U 12. Components made from PA-U are not fusion compatible with components made from other polymers. 5.2 Material for non-polyamide parts 5.2.1 General All components shall conform to the relevant ISO International Standard(s). Alternative standards may be applied in cases where a suitable ISO International Standard does not exist. In all cases, fitness for purpose of the components shall be demonstrated. The materials and the constituent elements used in making the valve (including elastomers, greases and any metal parts used) shall be as resistant to the external and internal environments as the other elements of the piping system and shall have an expected lifetime under the following conditions at least equal to that of the PA-U pipes conforming to ISO 16486-2, with which they are intended to be used: a) during storage, b) under the effect of the fluids being conveyed, and c) taking into account the service environment and operating conditions. The requirements for the level of material performance of non-polyamide parts shall be at least as stringent as that of the PA-U compound for the piping system. Other materials used in valves in contact with the PA-U pipe shall not adversely affect pipe performance or initiate stress cracking. The valve manufacturer shall ensure that any transition joint between polyamide and non-polyamide parts and the valve body fulfil the requirements of ISO 16486-3. 5.2.2 Metal parts All parts susceptible to corrosion shall be adequately protected, providing this is necessary for the durability and function of the system. When dissimilar metallic materials are used which can be in contact with moisture, steps shall be taken to avoid the possibility of galvanic corrosion.
5.2.3 Elastomers Elastomeric materials used for the manufacture of seals shall be in accordance with ISO 16010. Other sealing materials are permitted if proven suitable for gas service. As a regional requirement for CEN member countries, elastomeric seals shall conform to EN 682. 5.2.4 Greases and lubricants Greases or lubricants shall not exude onto fusion areas and shall not affect the long-term performance of the valve materials. 5.2.5 Assembly Ancillary components of valves shall be assembled according to the manufacturer’s procedures and any component used in the assembly shall not prevent conformity of the valve to this document.
ISO 16486-4:2022 pdf download – Plastics piping systems for the supply of gaseous fuels — Unplasticized polyamide (PA-U) piping systems with fusion jointing and mechanical jointing — Part 4: Valves
