Patent ID: 8183493

Claim:
A system for monitoring a weld operation, comprising: a first structure and a second structure configured to be disposed on different sides of a target material; an ultrasonic wave generator comprising two or more separate generating elements directly or indirectly coupled to the first structure and adapted to deliver a guided ultrasonic wave to the target material during the weld operation, wherein the two or more separate generating elements are at different angular orientations with respect to the first structure; an ultrasonic receiver directly or indirectly coupled to the second structure and adapted to receive the guided ultrasonic wave propagated through the target material; and a signal processor adapted to monitor a quality level of a weld by extracting a transmit time versus signal amplitude plot corresponding to a torsional ultrasonic mode by separating the torsional ultrasonic mode from the guided ultrasonic wave and by comparing the extracted plot to a reference transmit time versus amplitude plot that corresponds to an acceptable quality level.