This standard is a purchase specification for flanged steel pressure-relief valves. Basic requirements are given for direct spring-loaded pressure-relief valves and pilot-operated pressure-relief valves as follows:
– orifice designation and area;
– valve size and pressure rating, inlet and outlet;
– materials;
– pressure-temperature limits;
– center-to-face dimensions, inlet and outlet.
Nameplate nomenclature and requirements for stamping are detailed in Annex A.
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