METHOD OF MANUFACTURING TORQUE JOINT AND FORMING DIE

摘要

PURPOSE: A method is provided to form grooves of shaft direction and radius direction in an equiangular tubular joint by using inner electromagnetic force between the ridges formed in a cylindrical surface surrounding the inner part of an outer die structure. CONSTITUTION: A method comprises the steps of:surrounding the overlapped part of a tubular member having an annular die with an inner cylindrical surface facing the outer surface of the overlapped area; inserting a coil piece connected to an electric energy source to extend the coil piece from the annular die to the overlapped area; and supplying electromagnetic force to inside the tubular member formed in the overlapped area by using the coil piece to generated changing force expanding the tubular member in the overlapped area to radial and outward directions.