This European Standard specifies the requirements for the design; manufacture and testing of safety valves for cryogenic service; that is to say for operation with cryogenic fluids (as defined in EN 1251-1) below-10 ℃ in addition to operation at ambient temperature. It is a requirement of this European Standard that the valves comply with EN ISO 4126-1 or EN ISO 4126-4. In the event of different requirements; the requirements for cryogenic service are applied. NOTE 1 A cryogenic fluid (refrigerated liquefied gas) is a gas which is partially liquid because of its low temperature (including totally evaporated liquids and supercritical fluids).This European Standard is restricted to valves not exceeding a size of DN 100 for category B. The valves of category A are limited to DN 25 and set pressures up to 40 bars. Both categories are designed to relieve single phase vapours or gases. A valve can be specified; constructed and tested such that it is suitable for use with more than one gas or with mixtures of gases. NOTE 2 All safety valves covered inThis European Standard correspond to category IV of PED (Directive 97/23/EC) and category 3 of TPED (Directive 99/36/EC). NOTE 3This European Standard does not provide methods for determining the capacity of relief valve(s) for a particular cryogenic vessel. Such methods are provided in EN 13648-3.
EN 13648-1:2008 history
2008EN 13648-1:2008 Cryogenic vessels - Safety devices for protection against excessive pressure - Part 1: Safety valves for cryogenic service
2002EN 13648-1:2002 Cryogenic Vessels - Safety Devices for Protection Against Excessive Pressure - Part 1: Safety Valves for Cryogenic Service