PURPOSE: To simply join integrally both members by forming a projecting hole flange part in one of two tubes, etc., and forming a recessed hole flange part in the other, fitting the projecting hole flange part into the recessed hole flange part and joining peripheral edges of the fitting parts.
CONSTITUTION: As for a heat exchanger 1, six tube materials 2-1 - 2-7 are bundled and joined integrally, and each of these pipe materials in constituted of an outer cylinder 3 and an inner cylinder 4 of a double cylindrical structure, and the upper and the lower ends are closed up by ring-like cover members 5, 6. In the outer cylinder and the inner cylinder, ring-like chambers S1 - S7 are formed and in other pipe materials than the center tube material, partition plates 11 - 16 are provided. By burring, a projecting flange part 3d and a recessed flange part 3e are formed on the upper and the lower sides of the outer cylinder 3 of the tube material, respectively, both of them are fitted and peripheral edges of fitting end parts are welded, and a passage 9 for allowing the chamber S3 and the chamber S4 to communicate with each other is formed. In such a way, while forming the passage between both the members at a low cost and simply, both the members can be joined integrally.
OHARA AKIRA
ONO MASAHIRO
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