The proximity effect and its application to the concentration of heating currents in predetermined strips

IN ANY industrial operation such as welding, concentration of heating currents in particular parts of the metal presents obvious advantages. A method is described in this paper of concentrating these heating currents in predetermined strips of conducting plates, pipes, or other shapes. These are placed in close proximity to each other or to auxiliary conductors. They are so interconnected that heating currents concentrate largely in adjacent strips in close proximity to each other and in which the current flows in opposite directions. The shapes are connected with sources of alternating or oscillatory current of moderately high frequency. The method therefore consists in the use of an enhanced “proximity effect” to control the distribution of heating currents in bodies.