LINER PIPE AND METHOD FOR MANUFACTURING THE SAME

摘要

PROBLEM TO BE SOLVED: To restore a liner pipe so as to have an almost round cross-sectional shape when the liner pipe is restored within an existing pipe, to certainly join a saddle branch joint or the like to the liner pipe at the time of joining, and to restore the liner pipe so as to have a pipe wall uniform in wall thickness over the entire periphery of the liner pipe. SOLUTION: The liner pipe 10 is held in an up and down direction to be made flat so as to get into a folding habit and the flat pipe 10 applying the folding habit thereto is heat-treated at a predetermined temperature, in a folded state to make it possible to prevent restoring force ready to return the flat pipe 10 to the original liner pipe 10 having a circular cross section from acting on the flat pipe 10, when the flat pipe 10 is inserted into the existing pipe having a bent part to be heated. Since the push-in part 20a of the folded pipe 10 is not plastically deformed, the flat pipe can be restored so as to have the round cross-sectional shape by heating and pressing the pipe 10 from the interior thereof and the wall thickness of the push-in part 20a does not become thin.