It is spread the guide wave whose phase velocity

摘要

PROBLEM TO BE SOLVED: To ultrasonically inspect an inspection target at least a part of which is embedded, while suppressing the attenuation of guide waves.;SOLUTION: A guide wave transmitter/receiver 2 for receiving the trigger of transmission from a computer 4 applies a signal for driving the guide wave to a guide wave transducer 1 and the guide wave transducer 1 excites the guide wave 13 slower than concrete in sonic velocity to propagate the same to piping 11. The guide wave 13 axially propagates through the piping 11 and the component of the guide wave reflected from a discontinuous point due to cracks or reduced wall thickness is received by the guide wave transducer 1; and the receiving signal in which receiving waveform data is contained is inputted to the guide wave transmitter-receiver 2 to be amplified and the amplified receiving signal is converted into a digital signal, by an A/D converter 3 to be transmitted to the computer 4. Next, the computer 4 analyzes the receiving waveform data of the guide wave contained in the digital signal and calculates the position, in the axial direction of flaw from the appearance time of the signal.;COPYRIGHT: (C)2006,JPO&NCIPI