| 摘要 |
<p>PROBLEM TO BE SOLVED: To exchange a buried pipe without injuring a newly laying pipe by crushing an existing pipe buried in the earth while spreading the pipe, and drawing a newly laying pipe connected to a crushing means in crushed traces under the condition covered with a cylindrical covering body made of cloth. SOLUTION: A newly laying pipe 3 made of polyethylene pipe 3A to be drawn in instead of a crushed existing pipe is covered with a covering body 4A formed by folding canvas material such as nylon or aramid into two from the extreme end part extending over the full length and continuously sewing the end edge part in the width direction setting the outlet seam outside. On the extreme end of the incision part 7 of an existing pipe incision tool 6B, a fitting part to a rod 10 for taking it in the existing pipe is provided, the newly laying pipe 3 is connected to the rear part of a forcedly spreading part 8 through a connecting metal fitting 15, the existing pipe is incised by incision round blade 7a of which the diameters become larger from the extreme end, and the pipe 3 connected to a crushing means 6 and covered with a covering body 4A is covered with a guide bar 11. When it is put in the existing pipe, there is no possibility injuring the pipe 3.</p> |
