JPH05346295

PURPOSE:To improve operability by winding a tube material on a mold material for molding, removing a formed coiled tube from the material, and extending between a starting end and a finishing end of the tube to increase a pitch of the tube. CONSTITUTION:A long tube material is wound on a mold material 3 for molding, and coiled tube 4 in close contact are formed. Then, after the tube 4 is removed from the material 3, an interval between a starting end 4a and a finishing end 4b of the tube 4 is extended to increase a pitch of the tube 4. The tube 4 is so fixed to the material for fixing the tube that the extended tube 4 is arranged in a zigzag manner. It is aligned in parallel thereby to obtain a heat exchanger of a zigzag array by eliminating a brazing position. Thus, a heat transfer tube having high operability and high reliability can be obtained.