What Does
Plug For Manhole Mean?
Plugs for manholes are made of rugged rubber and normally used to perform spot leaks or test the air quality in an adjoining sewer. They are typically inflated and filled with an inert gas or water after being put in place. However, they may also be mechanical or consist of epoxy resin for more permanent installations. Operations in which plugs for manholes are used include air tightness tests, smoke tests, water tightness tests, and to deviate or divert effluents.
Trenchlesspedia Explains Plug For Manhole
Manhole plugs may also refer to materials used to block, vent and pick holes that allow inflow. In the past it was deemed necessary that manhole covers be constructed with holes in order to vent and prevent a build up of gases in the sewer. However, those worries have largely subsided and most agree that vents are not necessary.