The Manufacturers Standardization Society (MSS) of the Valve and Fittings Industry has recently published the new Standard Practice SP-156-2019, Ductile Iron, Metal-Seated, Non-Lubricated, Eccentric Plug Valves. SP-156 is maintained under the consensus of MSS Technical Committee 106, Cast Iron Valves.
This newly developed Standard Practice (SP)-156 establishes consensus-based manufacturing requirements for ductile iron, metal-seated, non-lubricated, eccentric plug valves with flanged, mechanical joint, grooved or shouldered ends. This standard includes all applicable eccentric plug valves in sizes and pressure-temperature ratings for general-purpose service and includes identified stipulations on chemical and mechanical material properties, dimensions and classes (designations) of end connections, valve pressure, and temperature ratings, workmanship, testing, coating, marking, and preparation for shipment.
Image credit: MSS