ULTRASONIC FLAW DETECTION METHOD

To provide an ultrasonic flaw detection method with which it is possible to accurately calculate the positions and the number of flaws.SOLUTION: The present invention includes the steps of: detecting a flaw in a material to be inspected for flaws using a plurality of array type ultrasonic probes; generating a two-dimensional image per ultrasonic probe with respect to a cross section; synthesizing two-dimensional images per ultrasonic probe and generating a general two-dimensional image of the entire cross section of the material to be inspected for flaws; and synthesizing the general two-dimensional images with respect to a plurality of cross sections in the longitudinal direction of the material to be inspected for flaws and generating a general three-dimensional image of the whole of the material to be inspected for flaws. In the flaw detection step, the plurality of ultrasonic probes are arranged so that there is an overlapping flaw detection area where each of the flaw detection areas of the plurality of ultrasonic probes overlaps. In the general two-dimensional image generation step, the two-dimensional images are synthesized so that all of prescribed reference positions located within the overlapping flaw detection area of two-dimensional images per ultrasonic probe match, in which way the general two-dimensional image is generated.SELECTED DRAWING: Figure 4 【課題】きずの位置や個数を正確に算出可能な超音波探傷方法を提供する。【解決手段】本発明は、複数のアレイ型超音波探触子を用いて被探傷材を探傷する工程と、超音波探触子毎に断面についての２次元画像を生成する工程と、超音波探触子毎の２次元画像を合成して、被探傷材の断面全体の全体２次元画像を生成する工程と、被探傷材の長手方向の複数の断面についての全体２次元画像を合成して、被探傷材全体の全体３次元画像を生成する工程とを含む。探傷工程において、複数の超音波探触子の探傷領域のいずれもが重複する部分である重複探傷領域を有するように、複数の超音波探触子を配置する。全体２次元画像生成工程において、超音波探触子毎の２次元画像の重複探傷領域内に位置する所定の基準位置が全て一致するように２次元画像を合成することで、全体２次元画像を生成する。【選択図】図４