Manhole cover for valve box, has fixed and mobile parts threaded interiorly and exteriorly, where mobile part rotates in fixed part to adjust height of cover with respect to fixed part, for positioning upper part of cover at ground

摘要

The cover has a fixed part (2) threaded interiorly on a large part of its length, and a mobile part (3) threaded exteriorly. The mobile part rotates in the fixed part to adjust the height of the cover with respect to the fixed part, to position an upper part of the cover at ground. The cover has a sleeve of length adapted to a raised value of valve box so that the cover is extracted vertically with the fixed part.