| 摘要 |
PURPOSE:To perform high-precision flaw detection by obtaining a decibel value corresponding to a weld zone and a decibel point for obtaining a evaluation point at the same time in such a state that they are in phase with each other in the lengthwise direction of the weld zone. CONSTITUTION:When an ultrasonic flaw detector A for the weld zone 2 connecting end parts of tubes 1a and 1b is constituted, the 1st - the 3rd probes 3a- 5a for transmission, the 1st - the 3rd probes 3b-5b for reception, and a measuring devices 6 equipped with a flaw detector 6a are provided. Then, an A/D converter 7 converts the measurement data received by the 1st - the 3rd probes 3b-5b for reception into digital signals, and the arithmetic processor 8 calculates evaluation points on the basis of the input information; and a plotter 9a outputs an evaluation line of evaluation points and decibel values corresponding to the weld zone 2 graphically on the basis of those signals, and a printer 10 prints three decibel values at specific circumferential positions of the tubes 1a and 1b and the evaluation points numerically. |
