초록 ▼

A watertight manhole insert is provided for preventing rainwater from entering a sanitary sewer system through manhole covers. The insert includes a shallow, dish-shaped body and a mounting flange designed to rest upon the supporting flange of a manhole frame. A recess is formed in the bottom of the

A watertight manhole insert is provided for preventing rainwater from entering a sanitary sewer system through manhole covers. The insert includes a shallow, dish-shaped body and a mounting flange designed to rest upon the supporting flange of a manhole frame. A recess is formed in the bottom of the body portion and includes a valve for releasing pressure which builds up beneath said insert. The valve is shielded such that it will not be struck by a manhole cover sliding across said insert. Additionally, the valve can be used as a handle to remove the insert from a manhole.

대표청구항 ▼

A watertight manhole insert for positioning beneath a manhole cover, said insert comprising: a mounting flange corresponding to a support flange of a manhole frame; a dish-shaped body depressed below said mounting flange less than the path of spin of said manhole cover on said supporting flange of s

A watertight manhole insert for positioning beneath a manhole cover, said insert comprising: a mounting flange corresponding to a support flange of a manhole frame; a dish-shaped body depressed below said mounting flange less than the path of spin of said manhole cover on said supporting flange of said manhole frame, said body including a recess formed in the lower portion thereof; and a valve located in said recess for releasing pressure which builds up beneath said insert.