Lateral shadow zone range corresponding to edge of part determination method for detecting e.g. bubble, in part, involves determining range of shadow zone from edge to surface of part by measuring effective section of ultrasonic beams

摘要

The method involves determining range of a shadow zone from an edge (34) of a submerged part (12) to a surface (22) of the part by measuring an effective section of ultrasonic beams (20). The range between a transducer (18) and the surface is equal to radius of section of the beam at the surface. The section is determined from echo amplitude variation of the beam according to the distance of the axis (40) of the beam at the edge.