| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an efficient method for removing an old pipe without excavating, the ground surface and laying the new pipe at the same time. SOLUTION: A steel wire is inserted into the old pipe from a vertical shaft, a linking means is fixed to an end portion of the oil pipe exposed in the vertical shaft at the start side, the tip side of the inserted steel wire is connected to the linking means, the steel wire is taken up to a winder installed in the vertical shaft at the arrival side and pulled out by applying a pushing force from the end portion to the old pipe at the start side, and the old pipe is taken up to the winder together with the steel wire. Also, in order to pull in the new pipe to be laid from the vertical shaft at the sending side to the hole at the same time with the removal of the old pipe, the linking means is fixed to the tip portion of the new pipe, the tip side of the steel wire previously inserted is fixed to the linking means, and the old pipe is taken up by the winder and pulled out and at the same time the new pipe is pulled by the steel wire into the hole from which the old pipe has been removed.</p> |
