| 摘要 |
PURPOSE:To elevate the reliability of flaw detection data by identifying sporadic defect signals as noise and a plurality of defect signals as defect echo among detection signals as obtained from a plurality of vibrators. CONSTITUTION:An ultrasonic wave transmitting section comprising a trigger 18, a channel converter and a pulser 20 transmits a time-division cycle signal to vibrators C1-C3 as excitation signal. Ultrasonic beams transmitted from the vibrators C1-C3 have different incident angles with respect to the inner surface of a pipe and corresponding reflected echoes are inputted into the ultrasonic wave receiving section. In the ultrasonic wave receiving section, the reflected echoes are outputted as defect signal when higher than the specified level value with a comparator 22 and as defect fetching signal from an AND circuit 26 or an OR circuit 27 when the number of defect signals is more than one as generated while the probe turn three times, namely vibrators C1-C3 each turn once. And furthe, the signal giving the maximum values is taken out with a high value preference circuit 25 from the defect signals. |
