A MANHOLE

摘要

A manhole equipped with a spiral circulation plate is provided to drain water gradually without an auxiliary pipe as the manhole is made up of a dual pipe in which the spiral circulation plate is installed between the inner and outer pipes. A manhole comprises an inner pipe(12) in which a drain pipe(26) is installed on one side, an outer pipe(14) which is inserted outside the inner pipe and equipped with an inlet pipe(22) positioned above the drain pipe, and a circulation plate(18) which is the space(16) between the inner and outer pipes to circulate the water discharged from the inlet pipe. The circulation pipe is placed along the peripheries of the inner and outer pipes in the shape of spiral so that the end(18a) of the spiral is connected to a hole(24) formed on the lower end of the inner pipe.