CONTINUOUS HIGH-SPEED WELDING METHOD OF DOUBLE-WOUND METAL TUBE, AND WELDING FURNACE THEREOF

摘要

PROBLEM TO BE SOLVED: To consistently and continuously produce a double-wound metal tube used for a brake tube, etc., for a car according to the tube-manufacturing speed. SOLUTION: The welding speed is increased to keep the balance with the tube-manufacturing speed by using the high-temperature reducing molten salt of a large calorific capacity as a heating medium.