Manhole cover for roadway has an elastic damping seal fitted to the underside and with a radial lip extending over the diameter of the cover to provide horizontal damping

摘要

A manhole cover (2) set into a roadway is supported on an even surface shelf (4) around the inside top of the shaft. The outer edge of the cover is fitted with an elastic sealing and damping ring (3) fitted into a trapezium shaped groove (5) under the cover and with a radial lip (6) extending past the diameter of the cover. The lip is sufficiently wide to fit into the stepped shelf of the fitting and to stabilise the horizontal movements of the cover when displaced by heavy traffic. The elastic seal is made in one piece and a dovetail fitting can be used as an alternative to the trapezium fitting.