This part of ISO 4126 specifies general requirements for pilot-operated safety valves, regardless of the medium for which they are designed. In all cases, the function is triggered by the medium in the system to be protected. The standard applies to pilot-operated safety valves with a narrowest flow diameter of at least 4 mm and for response pressures of at least 0.1 bar. Temperature limits are not specified. This standard is a product standard and does not address applications for pilot operated safety valves.
EN ISO 4126-4:2013 Referenced Document
ISO 4126-7:2013 Safety devices for protection against excessive pressure - Part 7: Common data
EN ISO 4126-4:2013 history
2013EN ISO 4126-4:2013 Safety devices for protection against excessive pressure - Part 4: Pilot-operated safety valves
2004EN ISO 4126-4:2004 Safety devices for protection against excessive pressure - Part 4: Pilot operated safety valves ISO 4126-4:2004