| 摘要 |
PURPOSE:To make it possible to simultaneously observe plural signal patterns differing in flaw detection frequency, by time-dividing a multiple parallel output signal of respective flaw detection frequencies outputted by a probe and in the same time by selecting a desired flaw detection frequency. CONSTITUTION:While multifrequency eddy current defectoscope 8 operates and probe 1 moves in the direction shown by arrow 6 to detect structure 3 of outside of thin pipe 2 and defect 4 of thin pipe 2, the output of defectoscope 8 is inputted to signal display device 13. Respective flaw detection frequency signals are inputted to switch circuits 37-44 via impedance converting circuits 29-36 and time-divided, and then they are applied to the input terminals for X- and Y-axial deflection of recorder 9 via impedance converting circuits 49 and 50. To display only an optional flaw detection signal pattern, the brightness of a spot is made zero by the time width with which a flaw detection signal of a frequency undesired to display draws a pattern. Thus, the necessary number of signal recorders can be decreased. |
