Lamb wave ultrasonic probe for crack detection and measurement in thin-walled tubing

摘要

A probe inspects steam generator tubing for defects. The probe includes a transducer which generates a localized ultrasonic Lamb wave. The ultrasonic wave is transferred to the tubing by a coupling medium, such as water, that physically couples the transducer and the tubing. Defects in the tubing reflect the ultrasonic wave to the probe which detects the reflections. The results are then used to determine the length and depth of such defects as cracks, pitting, and thinning. The localized ultrasonic wave performs an inspection sensitive enough to detect ligaments between crack segments. This allows highly accurate predictions of tubing integrity and rupture strength.