METHOD FOR ULTRASONIC CONTROL OF WELD JOINTS

摘要

The invention concerns a method for non-destructive ultrasonic control, combining time-of-flight diffraction and inclined longitudinal wave techniques, of weld joints (1) assembling two abutted parts (2, 3).Therefor, the method consists in, using the time-of-flight diffraction technique, displacing in the longitudinal or circumferential direction, along the weld joint (1) to be controlled, at least one pair consisting of a first transducer (5) and of a second transducer (6), one transmitting and the other receiving ultrasonic waves, said transducers (5, 6) being laterally positioned on either side of the joint (1) to be controlled, said transducers (5, 6) comprising piezoelectric ceramics or crystals, so as to detect any defect in the joint (1, 50) located at a thickness of at least 5 mm. Furthermore, it consists in displacing along the welded joint (1) to be controlled, using the inclined longitudinal wave technique, at least a third transducer (57, 53, 54, 55), so as to detect any defect of the joint (1, 50) located at a thickness ranging between 0.5 mm and 15 mm. The invention is applicable to manufacturing and operating controls, in particular for weld joints of walls of components under pressure.