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125mm circular HDPE flap valves are for use with pipework up to 125mm. Circular flap valves are recommended for use in emergency situations to protect against and prevent flooding during periods of extreme weather. Our circular flap valves are usually installed above the normal water level to prevent back flow up a pipe during times of heavy rain and flooding. The PTK-G flap valve is suitable for use with a water pressure of 5 MWC for 72 hours and 1 MWC for 50 years. Althon circular flap valves are HDPE with HDPE ribs and can be further reinforced where necessary with stainless steel.

  • 125mm Flap Valve for pipework up to 125mm
  • 10mm opening pressure when submerged 
  • Lightweight, easy to install and handle
  • Easily adaptable to meet site specific pressure or installation demands
  • 50 Year design life

The flap valve is HDPE with HDPE ribs and can be further reinforced where necessary with stainless steel

The valve plate and the back plate are manufactured in HDPE. The hinge pin and ballast weight are manufactured in SS316 as standard. The ballast weight can be easily adjusted if required. The sealing arrangement consists of an EPDM lips seal in the back plate. The valve plate is also installed on an angle in relation to the back plate to ensure a good seal. 

Please note drawing is for visual purposes only and not to scale

All dimensions in millimetres

If you require any assistance or more information please contact us by phone on 01603 488700 or by email

125mm Circular Flap Valve line drawing
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125mm Circular Flap Valve

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    125mm Circular Flap Valve

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