Commercial Marine Flow Switches

Gems™ flow switches provide thoroughly dependable protection of shipboard systems utilising liquid flow in their operation.  Made to monitor specific flow rate setpoints, Gems flow switches are used to initiate automatic shutdown or actuate alarms in the event flow falls off, exceeds or otherwise fails to meet established parameters.  Use Gems flow switches in heating, cooling, lube oil systems, or any other critical flow area in a vessel.  They utilise our reliable reed switch technology which responds to true fluid flow, and isn't affected by pressure changes.  And because they are Gems sensors, these flow switches feature only the highest quality, corrosion-resistant materials for use in the toughest marine environments.

Two Unique Operation Designs
Simple in Concept, Gems flow switches are sophisticated in design.  They respond only to true fluid flow, and are unaffected by changes in line pressure that can cause false readings in other types of sensors.

Shuttle Type switches use a shuttle which, when displaced by fluid flow at a preset rate, actuate a hermetically sealed, SPST or SPDT reed switch within the unit's stem.  Either a compression spring or gravity provides shuttle return when flow decreases.

Paddle Type switches feature cam action.  When liquid flow in either direction deflects the paddle it rotates an attached cam, which then displaces a permanent-magnet-equipped shuttle along the unit's stem.  The magnet actuates a hermetically sealed, magnetic reed switch within the stem.  Paddles are cut to provide specific setpoints and to allow use in a range of pipe diameters.  They provide flow/no-flow detection where there is a fluid velocity of at least 0.5ft. per second (152 mm per second).

When actuated, these switch units are used to operate remote alarms, indicators and annunciators, pumps, motorised valves, or are integrated into automatic system controls.

FS-550 FS-550 - Paddle Flow Switches
Sensing flow in either direction to monitor flow/no-flow conditions, Gems paddle switches are cut to size to fit a variety of pipe sizes from 1-1/4" and up.  The unique, patented cam design assures low pressure drop, and requires no bellows, seals, or mechanical linkages.  They are supplied in two paddle lengths and can be trimmed during installation to permit switch actuation at the desired flow rate.  Available with brass or stainless steel housings, 316 stainless steel paddles, and Teflon®, Viton®, and ceramic wetted parts.  Temperature capability ranges from -30°F to +300°F (-34°C to +149°C), and pressures to 2000 psig (138 bar).  Threaded or flange mounted versions available.

FS-200 FS-200 - Shuttle Type Switches  
Rugged shuttle type flow switches are used for moderate to high flow rate applications.  A broad range of models allow flow actuation settings from .5 GPM to 150 GPM (1.9 I/min to 568 I/min).  They provide 1% repeatability over a broad range of flow settings and port sizes.  The shuttle design offers generous flow paths to keep pressure drop low, and a choice of flange NPT, socket weld, and union end connections provides versatility.  Available in bronze or stainless steel housings with Teflon®, and ceramic wetted parts.  They handle temperatures of  -20°F to +300°F (-29°C to +149°C), and pressures to 400 psig (27 bar).

Call the Marine Product Specialists at Gems Sensors & Controls at 1-855-877-9666 for assistance or click here for authorised Marine product representatives.