摘要 |
A sealing member for use in well shafts. The sealing member comprises a hose which is mounted over a tube sleeve and is sealed at its ends relative thereto. At least one pipe carrying pressurized water passes through the sleeve. The pressurized water pipe is connected with a space between the sleeve and the hose, and the connection means includes a valve arranged to allow water to flow from the pressurized water pipe to the space but not in the opposite direction. Through this arrangement the pressurized water inside the space between the hose and the sleeve keeps the hose in sealing engagement against the wall of the well shaft. |