SEALING METHOD FOR END PART OF HOLLOW MATERIAL FOR COIL SPRING

摘要

PURPOSE: A sealing method for end part of hollow material for coil spring is provided to prevent coating inferiority by preventing penetration of water. CONSTITUTION: The hollow material(10) for coil spring bar is fixed to a chuck of a rotating device. The rolling jig(11) of the rotating device is carried to the hollow material for coil spring. The end tip of the hollow material is inserted to the inside of the mechanical groove(110) of rolling jig. The rolling jig is rotated and the end tip of the hollow material inserted into the mechanical groove is heated with the frictional heat. The end tip of the hollow material is heated with rotational friction of rolling jig. The rolling jig is more carried to the hollow material. The end tip of the hollow material is pushed into a hollow portion(100) and thermally fused.