API RP 621
Recommended Practice for Reconditioning of Metallic Gate, Globe, and Check Valves
standard by American Petroleum Institute, 03/01/2001
Full Description
API RP 621 provides guidelines for reconditioning heavy wall (API 600 type) carbon steel, ferritic alloy (up to 9% Cr), stainless steel, and nickel alloy gate, globe, and check valves for ASME pressure classes 150, 300, 400, 600, 900, 1500, and 2500. Guidelines contained in this RP apply to flanged and butt weld cast or forged valves.