Dry trap valve for use in a non-flushing urinal and other drains

摘要

A dry trap valve is disclosed which includes a holder (34) in the form of a generally planar ramp having an entry (32) for receipt of the wastewater. A sealing flap element (50) covers a passageway (36) in the holder. The sealing element (50) is disposed to lift upon flow of the wastewater through the valve and to close in the absence of the flow under the influence of gravity. The valve is particularly suited to use in a non-flushing urinal where the seal is increased under gas back pressure from a sewerage system.