摘要 |
SEWER CHECK VALVE WITH CUTTING SEAT In place of one of the usual blunt seats, a sewer check valve has a knife-edge extending from one of the seats to eliminate holding of compressed, relatively tough chunks of sewage between seats by cutting through the chunks, and has room for the cut pieces to move away from the seats. The flap of the valve has a lever extending therefrom, and a spring actuated rod retained by a catch is released to strike against the lever for forcing the flap against the knife-edge. The catch may be released manually, but is preferably released by slightly delayed operation of a solenoid in response to operation of a level sensing device in the housing of the valve. |