The Flapstopper Box Valve

The Box Valve version of the Flapstopper is a revolutionary solution that overcomes the issues associated with opening a Flapvalve under a head of water. It also provides access to the mechanism for inspection and servicing without having to remove the valve from its mounting.


Designed and manufactured in the UK from corrosion, resistant, stainless box valves can be fabricated to suit drains and sewers from just 10cm to over 1m in diameter.  With the larger diameters, it is commonplace to reduce the size of the actual valve fitted to reduce the flow when opening and to make the Flapstopper and the Box act as a combined flow attenuator. By reducing the size of the flap, leakage and cost are both reduced, and a tsunami water flowing upon opening is reduced significantly, reducing the risk of structural damage downstream.


The controls for the Box Valve are identical to that of the standard Flapstopper which can both be automated using radio telemetry, call points or smart in-drain sensors.

Reverse Mounted Pollution Containment Box Valve 160mm in stainless steel

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