Flanged Steel Pressure-relief Valves

8th Edition

Published by American Petroleum Institute, 08/01/2023


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API STD 526, 8th Edition – Flanged Steel Pressure-relief Valves

API 526 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 [metric units (SI)] and Annex E [U.S. customary units (USC)].

General Product Information:

Revision 8th
Document Type PDF
Pages 160
Document Language English
Publisher American Petroleum Institute (API)
Status Current


Document History