Swagelok SS-3NBS4-W20 Needle Valve

SS-3NBS4-W20 is a stainless steel severe-service union-bonnet needle valve with 1/4 in. Swagelok tube-fitting end connections and a Cv of 0.35, designed for precise throttling and isolation in high-pressure process lines. Constructed from 316 stainless steel, it handles working pressures up to 10,000 psig (689 bar) and operates across broad temperature ranges depending on packing: PTFE packing supports -65 to 450°F (-53 to 232°C), while Grafoil packing extends service up to 1200°F (648°C). The W20 suffix indicates a hydrostatic test performed to Swagelok standards, ensuring integrity under pressure before installation. Typical applications include instrumentation panels and high-pressure gas or liquid service in chemical processing, petrochemical, and other demanding process environments where precise needle-valve control and reliable isolation are critical.