Method and apparatus for ultrasonic flaw detection.

摘要

A method and an apparatus of ultrasonic flaw detection suitable for detecting internal cavity defects in a material (2), the method comprising: mounting on a rotary body (7) a plurality of inclined probes in equidistant positions in the circumferential direction of the rotary body (7) to provide a corresponding number of channels for transmitting and receiving ultrasonic beams in a direction intersecting the axis of rotation of the rotary body (7) at different depths in an inspection zone.of a material (2) positioned opposite to the probes; turning the rotary body (7) to revolve the probes through 360° about the axis of rotation while transmitting and receiving ultrasonic pulses;producing detected flaw patterns from the peak values of the echoes received at the detection gates of the respective channels in relation with the direction of incidence of the ultrasonic beams: and deciphering the direction, inclination. size and depth of a detected defect from correlation processing of the detected flaw patterns with a number of predetermined reference patterns for judging the severity of the detected defect.