Patent attributes
A pressure cap having a generally cylindrical hollow body with a semispherical cap having an orifice defined within and passing through said cap, a valve stem passing through and of smaller cross-section than the orifice, a valve member supported by the valve stem within the hollow body, a valve seat surrounding the inner end of the orifice and upon which the valve member is normally seated so as to close the orifice, and mateable threading to attach to an existing pipe, or attach by frictional fit. It may also have a rubberized flange to fit over a drain line for pressuring a drain and any of a variety of valve stem configurations to accommodate different pump systems and access requirements. Further, a method for clearing an obstructed pipe using a pressure cap as disclosed. In another embodiment a balloon is positioned within the pipe to receive pressurized air until bursting, thereby sending a blast of air down the pipe to clear obstructions.
