| 摘要 |
PROBLEM TO BE SOLVED: To judge with high reliability the severity of a flaw in a subject for examination, such as a railroad rail, by performing appropriate evaluation that matches the kind of the flaw. SOLUTION: Ultrasonic pulses are radiated to a rail 10 through a multichannel ultrasonic wave transmitting/receiving part 12 through an ultrasonic probe 11, and a reflected echo at each of plural channels is detected by a reflected echo detecting part 13. A connection area of the detected reflected echoes on a B-scope image is extracted by a connection area extracting part 14. Magnitude and end-point position on the B-scope image, the central value of the input signal level of the reflected echoes constituting the connection area, and the central value of the beam path of the reflected echoes are calculated by a feature amount extracting part 15 as the feature amounts of the connection area, and the kind of a flaw is identified by a flaw-kind identifying part 16 from the kind of the channel and the central value of the beam path of the reflected echoes extracted. The severity of the flaw is judged by a severity judging part 17 on the basis of the kind of the flaw, the magnitude and end-point position of the connection area on the B-scope image, and the central value of the input signal level of the reflected echoes. |
