Water drain non-return valve - has sump in ground with upstream strainer fixed to access hatch

摘要

The non-return valve is for installation in a water drain, having a sump in the ground with a removable top hatch, and grille. Upstream of the valve is a strainer retaining the coarse dirt. The strainer (16) is fixed to one or more sections of the hatch (2,3,4), or to a support for the latter. It can be in one piece with the inlet grating (2), or with the hatch (3) covering the components (10,11) of the non-return valve.