REPLACING CONSTRUCTION METHOD OF GAS TRANSPORTING CONDUIT AND PIPE END SEAL DEVICE

摘要

PROBLEM TO BE SOLVED: To efficiently perform replacing work of city gas conduit or the like. SOLUTION: Replacement of a city gas conduit is performed to be divided in a plurality of days. An excavation pipe L2 on a first day is taken longer than a replacing section L1, old pipes 2a, 2b are left in both sides. The out of the old pipe 2a, 2b in both sides of the replacing section L1 is air-tightly closed by inserting a gas bag 5a, 5b from an insertion hole 4a, 4b. A replaced new pipe 3 is polyethylene-made, one end side is connected through a sleeve 6 and a transition joint 7. In the other end side, a stopper 8 is inserted. The stopper 8 is expanded when a fluid is supplied through a hose 9, an end part of the new pipe 3 can be airtightly closed. In the other end of the new pipe 3, an end cup 10 is mounted. When a cover body 11 is removed, the hose 9, in a condition air-tightly sealed, can be drawn out to the outside. In work on the next day, the stopper 8 is expanded, the end cup 10 is removed, after the new pipe is connected, the stopper 8 is moved in the new pipe.