| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an easily manufacturable double tube type heat exchanger capable of serving also as a part of a pipe by bending the whole smoothly and having high pressure proofing property. <P>SOLUTION: An internal tube 1 is constituted in such a way that a plurality of swelling parts 7a having cross section like bag or balloon are formed in the radial direction from the center on cross section at a right angle for its axial line, a port of the swelling part 7a is blocked, and a tip of each swelling part 7a comes into contact with an inner face of an outer tube 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
