Most industrial valve companies (including Special Alloy Fabricators) manufacture their products to the specifications outlined in the following codes and standards for design, fabrication, testing and quality control.
ASME B16.34: Valve Design & Testing
ASME B16.5 & B16.47: Flange Ratings & Construction
ASME SECTION VIII DIV 1: Non-Destructive Examination
ANSI FCI 70-2: Control Valve Seat Leakage Classifications
MSS-SP 81 AND 135: Valve Pressure Ratings & Face-to-face Dimensions