Dwyer Instruments, Inc.

Oct. 11, 2007
Flap Check Valves Keep Backflow in Check

Dwyer's new Series FPV Plastic Flap Check Valves are suited to areas where backflow could potentially cause damage to pumps, filters, or process equipment. The valves operate without the need for any adjustments or settings.  Line pressure moves the solid plastic flap off the elastomer seat, opening the valve. When the inlet flow stops, back pressure moves the flap back onto the seat, stopping the flow.  

These flap check valves have been designed to provide excellent flow characteristics, and because of their straight-through flow design they have a lower pressure drop than other check valve designs.  Additionally, their compact size takes up less space in the pipeline than other types of check valves.  Because of their all plastic construction, these valves will never jam or stick as a result of rust or corrosion, and they will not contaminate sensitive fluids that come into contact with them, according to the manufacturer. These valves are available in 4-inch, 6-inch, and 8-inch sizes and feature EPDM O-rings and silicone free-construction.