Flanged, Duck Bill Check Valves
Style 4200
Features:
- Reliable and cost-effective alternative to flap-gate and other conventional check valves
- Eliminates backflow and seals around entrapped solids
- Rugged all-elastomer construction
- Maintenance-free operation with no mechanical components that can corrode or seize
- Lower head loss than conventional check valves
- Will open with as little as 1" W.C.
- Quiet operation (non-slamming)
- Non-plugging
- Excellent corrosion and abrasion resistance
- Versatile construction for a wide range of applications
- Manufactured with an integral reinforced rubber flange provided with metal retaining rings for easy bolting directly to the pipe flange, tank wall or head wall
- Flanges drilled per standard ANSI B16.1/150 lb. pattern; other drilling patterns are available upon request
- Retaining ring available in galvanized, 304 stainless steel and 316 stainless steel
- Wide variety of sleeve elastomers available for different abrasion and corrosion service conditions
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Typical Applications:
Storm Water Outfall/Overflow: The Flex-Valve® Style 4200 Duck-Bill check valves provide quiet, maintenance-free operation with an added benefit of low opening pressure. The low opening pressure eliminates standing water – a major health concern.
Submerged Outfall Diffuser: The Flex-Valve® Style 4200 Duck-Bill check valves will eliminate marine fouling and backflow intrusion with an added benefit of higher jet velocities. The high jet velocity is also found at low flow rates, providing a more uniform port discharge distribution. The versatile construction and our creative design team can adapt the Flex-Valve® Style 4200 Duck-Bill check valves to additional applications including, but not limited to: water mixing systems, overflow vents, anti-siphon devices, course bubble diffusers, floor drains, sparging devises, or when needed, a devise to increase back pressure in a pipe line.

Notes:
- Dimensions are subject to change due to customized construction.
- For full product specifications and installation instructions, see SPEC 4200-1 and ININ 4200-1.
- All dimensions expressed in inches. Contact General Rubber for sizes not shown and higher pressure ratings.
- Customer to provide head pressure and maximum back pressure when ordering.
