Swagelok S-18KF8 Integral Bonnet Needle Valve

Swagelok S-18KF8 Integral Bonnet Needle Valve is a compact stainless steel control valve designed for precise metering in instrumentation and sampling lines. Made from 316 stainless steel, it features an integral bonnet design to minimize leak paths and a regulating stem for fine flow adjustment. The valve is configured with 1/2 in MNPT inlet and 1/2 in FNPT outlet end connections, and carries a flow coefficient Cv of 1.80 with an orifice of about 0.375 in (9.5 mm) to support smooth throttling. Typical maximum rating is 600°F (315°C) at up to 3,130 psi (215 bar), enabling use in high-temperature, high-pressure applications, as long as the fluid is compatible with stainless steel and Swagelok fittings. Common applications include precise gas and liquid regulation in instrumentation lines, sampling circuits, calibration setups, and chemical processing feeds where tight shutoff and reliable repeatable control are essential.