PURPOSE: To prevent the coming off of plating by a method in which both ends of a pipe are closed by welding at axial end and a plating liquid is flowed from a pipe soldered to the axial end for plating treatment in case where the rotary shaft of a motor, etc., is made into a heat pipe.
CONSTITUTION: Both open ends of a pipe 1 are butt-welded with axial ends 2 and 3, and small-diameter pipes 9 and 10 are soldered to the axial ends 2 and 3 in such a way as to make them connect with a chamber 8 inside the pipe. Then, the pipes 9 and 10 are connected to a nonelectrolytic plating tank 11 and a plating liquid is circulated in the chamber 8 to apply plating to the inner surfaces of the chamber 8, the axial ends 2 and 3, and the small diameter pipes 9 and 10. Then, water as a working liquid is filled in the chamber 8 through the small diameter pipes 9 and 10 and the open ends of the pipes 9 and 10 are sealed up to obtain a heat pipe free of the coming off of plating.
TANABE MITSUO
AZUMA IZUMI