The primary application of flap valves is for surface water drainage associated with rivers, estuaries and seawater outfalls to prevent reverse flow conditions.
Flap valves can be utilised on final effluent outfalls for sewage treatment plant to prevent flood damage within the works. The flap valves should be positioned on the outfall structure to avoid the build-up of debris around the invert area which could prevent the valve operating correctly. Sufficient fall-away should be provided between the invert of the flap valve and the base of the outfall structure.
Flap valve application on sea water outfalls should be given careful consideration due to turbulence of flow across the flap, particularly when severe wave action is involved, resulting in dislocation of the flap relative to its seals. Wherever possible the flap valve should be located in a shielded position to minimise the effects of severe wave action.
Ham Baker Adams manufactures a comprehensive range of flap valves. Generally, most flap valves are of single door type but double door types are also available. The cast iron series of flap valves is constructed from traditional materials utilising the most modern production techniques to provide a robust and reliable product. Flap valves can be supplied for wall, flange or thimble mounting applications.