HDPE flap valves

Flap valves are used in sewage and drainage systems. They may be used both as an end-of-line units or as a part of a pipework. Their role is to prevent backflow of water or sewage back into the system. Flap valves may be mounted at discharge points of sewage systems or culverts (for agricultural drainage ditches and natural water courses) to effluent channels with an unstable water surface.

A flap valve works automatically and is activated by a water pressure acting upon the surfaces inside the system. The flap remains closed until the rising pressure of water flowing from the pipe opens it but closes when the pressure increases from the side of the receiver. The flap is properly balanced to permit smooth outflow of sewage from the system.

Flap valves are made from HDPE (high-density polyethylene) which is characterised by its resistance to corrosion and harmful substances in sewage. The flap valves comply with all requirements for plastics used in the construction of pipelines. The flap valves we provide can be mounted on a concrete wall of a sewer or drainage system outlet. They may also be adapted to be flange mounted or connected by means of straight couplers to the existing sewer system.

Bespoke flap valves may be manufactured to suit unique or special requirements concerning mounting.

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