API STD 599 specifies requirements for metal plug valves (quarter-turn, lubricated or non-lubricated) in petroleum, petrochemical, and industrial services. It covers:
Valve types: Flanged, threaded, socket-welded, or butt-welded ends.
Materials: Steel, nickel-based alloys, ductile iron (flanged ends only).
Size range: DN 15 - 900 (NPS 1/2 - 36) for flanged/butt-welded ends; DN 15 - 50 (NPS 1/2 - 2) for threaded/socket-welded ends.
Pressure classes: 150 to 2500 per ASME B16.34.
Key requirements include:
Design groups (short/regular/Venturi/full-bore patterns) with specific face-to-face dimensions.
Bidirectional sealing, material standards, and pressure-temperature ratings.
Testing/inspection per API 598 (shell integrity, seat leakage).
It ensures reliability for pipelines handling oils, gases, water, and steam.
