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flow sensors

Swagelok® Flow Sensors

Achieve accurate gas flow sensing with the positive actuation of Swagelok FV4 series flow sensors.

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Monitor changes in gas system flow with Swagelok FV4 series flow sensors. FV4 series flow sensors contain a snap-action float mechanism with a calibrated orifice that moves up or down in the float guide as flow increases or decreases, providing positive actuation for accurate sensing of gas. A magnet encased in the float above the orifice alternates electrical continuity between leads on an adjacent reed switch to detect flow changes.

An all-welded 316L stainless steel construction ensures fluid containment and enhances durability, and a replaceable switch assembly outside the flow path simplifies maintenance. FV4 series flow sensors are rated for working pressures up to 5000 psig (344 bar).


Material 316L SS
Temperature –40 to 175°F (–40 to 79°C)
Working Pressure Up to 5000 psig (344 bar)

Flow Sensor Catalogs

Locate detailed product information, including materials of construction, pressure and temperature ratings, options, and accessories.

Swagelok leak detection services

Compressed Gas Leak Detection Services

Receive help identifying and quantifying compressed gas leaks so you can prioritize the most critical issues to address based on potential for emissions reduction and safety, cost, and productivity improvement.

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