MULTI-LAYERED HEAT TRANSFER TUBE, METHOD FOR PRODUCING THE MULTI-LAYERED HEAT TRANSFER TUBE, AND MOLDING TOOL USED FOR THE METHOD

摘要

PROBLEM TO BE SOLVED: To provide a fin tube to be used for an open rack type carburetor, which has excellent heat transfer property, is capable of vaporizing liquefied natural gas, and has improved corrosion resistance to sea water by covering the entire outer circumference of the fin tube with a sacrificed anodic coating.SOLUTION: The multi-layered fin tube 2 having a plurality of fins 8 on the outer circumferential surface along the longitudinal direction comprises an inner tube material 4 in which a passage through which a liquefied gas flows along the longitudinal direction and an outer tube material 5 which covers the outer circumferential surface of the inner tube material 4, in its inside. At least the outer tube material 5 is composed of a fully dense material. All of the outer surface of the inner tube material 4 is covered with the outer tube material 5 and a metallic bond is formed on the interface between the outer tube material 5 and the inner tube material 4.