| 摘要 |
PROBLEM TO BE SOLVED: To surely capture only harmful scratches, to accurately and rapidly specify the reinspection position of ultrasonic flaw detection and a photograph location in X-ray photograph, to improve production efficiency, and to reduce costs for precise and sure detection of harmful scratches over the entire section of a welded section using a small number of ultrasonic probes, and for reducing adjustment time when steel pipe dimensions are changed, when performing the ultrasonic flaw detection of a welded steel pipe welded section. SOLUTION: Ultrasonic probes 3, 3 are installed sandwiching, while holding a welded section 2 in a welded steel pipe 1, ultrasonic probes 4, 4 are installed sandwiching directly above the welded section 2, one signal detected by one of a pair of probes is determined to be a reflection signal from a welded shape, when the signal is detected, and signals from both of the pair of probes are determined to indicate scratches, thus reducing erroneous detection by the fault of the welding shape. When scratches are detected, an alarm is outputted and is outputted to a recording paper, flaw detection is made again, circumferential marking striding over the welded section is executed, and X-ray photographing is executed. An ultrasonic probe in which the refracting angle can be varied is used, thus reducing the facility cost, or the like. COPYRIGHT: (C)2006,JPO&NCIPI
|
