Flow Sensors

Monitor changes in gas system flow with Swagelok’s Flow Sensors. Swagelok’s Snap-action float mechanism delivers positive actuation for accurate sensing so you can properly monitor gas system flow. The Swagelok FV4 series flow sensor contains a float with a calibrated orifice that moves up or down in the float guide as flow increases or decreases. A magnet encased in the float above the orifice alternates electrical continuity between the Black and the Red leads of the adjacent reed switch.


  • Electric switch actuated at pre-set level
  • Working pressures up to 5000 psig
  • Fluid containment ensured by all-welded construction
  • Replacement switch assembly is not inside flow path allowing for easier maintenance
  • Can be selected to sense either increasing or decreasing flow
  • All welded construction ensures positive fluid containment
  • Swagelok tube fitting ends, VCR and tube extensions for butt welding are available end connections

Swagelok products and assembly work are backed by our Limited Lifetime Warranty.

Browse Our Flow Sensors Catalog

Questions? Email or call 866.901.0151.