Sealing Plug for Closing Holes in Walls and the Like

A system comprising:

• a wall that holds a fluid, the wall having a hole defined by an inner surface of the wall,
• a plug for closing the hole in the wall, the plug comprising:
• an elastic body having a central axis, first end, a second end, an inner surface and an outer surface, the inner surface defining at least in part an internal cavity;
• and
• an elongate stem having a first part that resides inside the internal cavity and a second part that resides external to the elastic body protruding from the first end of the elastic body, the first part being operatively coupled to the elastic body so that a pulling on the second part causes the elastic body to axialy compress and radially expand to exert a first pressure on the inner surface of the wall that defines the hole when the plug is located inside the hole;
• the first end of the elastic body having a through opening that communicates the internal cavity with the fluid so that when the plug is located inside the hole the fluid applies pressure against the inner surface of the elastic body to cause the pressure applied to the inner surface of the wall that defines the hole to be greater than the first pressure.
• that extends through the inner surface to allow the internal cavity to communicate with the fluid held by the wall