| 摘要 |
PROBLEM TO BE SOLVED: To effectively prevent oxidation, which is easy to occur on internal surfaces of vertical pipelines when the vertical pipelines are jointed by soldering, by a simple method.SOLUTION: When a lower end part 11 of an upper pipeline 1 and an upper end part 12 of a lower pipeline 2 are jointed to each other by soldering, a bag body 20 is so attached to an upper end part 10 of the upper pipeline 1 as to be able of expanding and a non-oxidation gas is introduced in the interiors of the upper pipeline 1 and the lower pipeline 2, whereby the lower end part 11 of the upper pipeline 1 and the upper end part 12 of the lower pipeline 2 are jointed to each other by soldering after the bag body 20 is expanded. Since soldering can be carried out in a state such that air existing in the interiors of the upper pipeline and the lower pipeline is pushed into the interior of the bag body and the non-oxidation gas is filled in the interiors of the upper pipeline and the lower pipeline, an oxide film is not formed in the internal surfaces of the upper pipeline and the lower pipeline, whereby vertical pipelines can be prevented from jam and contamination. |
