Electron beam welding with automatic electron beam readjustment

The fusing zone of an electron beam-welded seam is verry narrow because of the small beam diameter. Therefore small deviations of the point of impact from the center of the welding gap will already deteriorate the welding result considerably. In order to guarantee the correct position of the point of impact of the beam along the whole welding seam, a readjustment system has been developed and built measuring and, if necessary, correcting the relative position of the point of impact of the beam and the welding gap with respect ot one another during the welding process. The measurement occurs intermittently at periodical intervals of time; as measuring system, the electron beam itself and the electrons reflected by the workpiece are used. The readjustment system allows an easier setting of the workpiece and welding also of seams which cannot be produced by other methods because of their complicated geometry. (orig.)