Manhole covering for sewer system, has cover inserted into frame for closing manhole, and projections accommodating set of aeration openings separated from each other by radial fins

摘要

The manhole covering has a frame attachable on a manhole and with a cover (1) that is insertable into the frame for closing the manhole, where the cover has a sag (2) filled with concrete (3). The sag has a circular periphery (4) and a majority of aeration sectors (5), where the sectors are projections extending along the periphery of the sag. The projections accommodate a set of aeration openings separated from each other by radial fins, where the number of aeration sectors is three. An independent claim is also included for a cover of a manhole covering.