PROCEDIMIENTO Y DISPOSITIVO PARA EL ACOPLAMIENTO DE UNOS CABEZALES ULTRASONICOS EN UNA PIEZA A ENSAYAR

Ultrasonic coupling method and device In the piece-by-piece continuous ultrasonic testing of material, there is a transient test condition in the end regions of workpieces. The new method and the new device are intended to guarantee the steady test condition even in the end regions. In a test head driven on a test track at a constant distance from the test piece, a layer of coupling medium is built up between sound emission surface and test piece surface with the aid of a separate free jet of the coupling medium arranged at the side of the test head and formed in a plane perpendicular to the test track containing the centre line of the sound emission surface. The method according to the invention and the apparatus according to the invention avoid the time-consuming manual inspection in the ultrasonic weld testing of longitudinally seam-welded pipes.