| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a double pipe enabling an inner pipe to be inserted into an outer pipe easily, and capable of easily and surely fixing the outer pipe and the inner pipe regardless of the dimensions in an extension direction of a straight pipe part and a bent part.SOLUTION: A process of manufacturing a double pipe 7 used as an internal heat exchanger of a refrigeration cycle 1 mounted on a vehicle includes: an insertion process of inserting, into an outer pipe 12, an inner pipe 11 having an outer diameter smaller than an inner diameter of the outer pipe 12; and a fixation process performed after the insertion process, of fixing the outer pipe 12 and the inner pipe 11 by making a part of the outer pipe 12 recessed until contacting with the outer periphery of the inner pipe 11. Then, the fixation process is, for example, a process of making the outer pipe 12 recessed so that a plurality of bottomed hole 22 exists in a scattered manner.SELECTED DRAWING: Figure 4 |
