DIN EN ISO 4126-4:2013-12

This part of the International Standard specifies general requirements for pilot operated safety valves, which are not covered by part 1, irrespective of the fluid for which they are designed. In all cases, the operation is carried out by the fluid in the system to be protected. It is applicable to pilot operated safety valves having a valve flow diameter of 6 mm and above which are for use at set pressures of 0,1 bar gauge and above. No limitation is placed on temperature. This is a product standard and it is not applicable to applications of pilot operated safety valves. This document has been prepared by Technical Committee ISO/TC 185 "Safety devices for protection against excessive pressure" in collaboration with Technical Committee CEN/TC 69 "Industrial valves". The responsible German committee is Working Committee NA 003-01-10 AA "Sicherheitseinrichtungen gegen Drucküberschreitungen" ("Safety devices for the prevention of excessive pressure") of the Valves Standards Committee (NAA) at DIN e. V.