| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To facilitate close contact of a helical tube, which is formed by spirally winding a strip-like profile, to an inner surface of a sewer pipe. <P>SOLUTION: A helical tube 10b partially recessed in a peripheral direction, is formed sequentially in a sewer pipe 20 by spirally winding a flexible profile 10 and joining its abutting ends mutually, using a tube production machine 40 arranged in the sewer pipe 20. Then, the helical tube 10b is made to restore a circular cross section in close contact with the inner surface of the sewer pipe 20, by projecting the recessed part of the helical tube 10b. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
