Apparatus and method for finding of defects, in particular in the form of material tears, in a rotationally symmetrical test specimen from a material having at least metallic parts of the material

摘要

Device for finding of defects, in particular in the form of material tears or surface defects, in a rotationally symmetrical test specimen from a material having at least metallic material, with electromagnetic ultrasonic transducers (emus), the horizontally polarized transverse waves (sh - waves) to generate and / or in the position to detect by means of a two-sided directional characteristic, and at a distance from one another to the electro-acoustic coupling in a common cross-sectional plane by the rotationally symmetrical test object at a freely accessible surface of the unit under test are in contact, as well as to an evaluation unit, which with the ultrasonic transducer acting as a receiver is connected,characterized in that at least two ultrasound transducers serving as a receiver at a distance from one another along the circumferential edge of the cross-sectional plane by the unit under test are arranged,that in the center between each two adjacent receivers each ultrasonic transducer which serves as a transmitter along the circumferential edge is arranged, andthat the receiver for signal evaluation are connected with the evaluation unit, the measuring signals originating from a receiver is inverted and subsequently with the measurement signals of the other..