METHOD FOR NON-DESTRUCTIVE TESTING OF A WELDING JOINT FORMED BY A LOST ELEMENT WELDING TECHNIQUE, SAID LOST ELEMENT BEING A WINDING, AND CORRESPONDING ARRANGEMENT

摘要

A method of nondestructive testing of a weld formed using the electrofusion technique, the method comprising the steps of:- exciting (100) a heating coil in a welding zone having the welding zone between at least two components welded together via the heating coil with at least one excitation signal with an excitation signal amplitude and an excitation signal frequency or an excitation signal frequency sweep with varying excitation signal frequency to a vibration;- varying (200) the exciter signal with respect to the exciter signal frequency and / or the exciter signal amplitude with which the heating coil is excited and determining (300) at least one resonance signal, in particular a resonant signal amplitude or a resonant signal frequency, the welding zone or the components welded together;- comparing (400) the determined resonance signal with at least one reference value for the resonance signal of the welding zone or of the components welded to one another, wherein a proper weld is concluded when a deviation between the determined resonance signal and the at least one reference value does not exceed a maximum value. It will be further described a corresponding arrangement.