| 摘要 |
PROBLEM TO BE SOLVED: To execute a sound seal welding and to reduce the man-hour by inserting an expanding and cooling jig into a flat tube, making an end plate in close contact with the flat tube and executing seal-welding. SOLUTION: A flat tube 3 is thrusted in an end plate 2, an expanding and cooling jig 1 of copper is inserted into the flat tube 3, the flat tube 3 is expanded and the gap between the end plate 2 and the flat tube 3 is eliminated. A flange 2a is formed in the part of hole into which the flat tube 3 of the end plate 2 is inserted and comes into close contact with the external circumference face of the flat tube 3. In this state, the end plate 2 and the flat tube 3 are seal-welded by a TIG welding torch 5. Since the gap between the end plate 2 and the flat tube 3 is eliminated, the sound welding part without the erosion part can be obtained by the cooling action of the expanding and cooling jig 1. |
