電磁超音波共鳴法を用いた配管減肉検査における底面形状の影響
Influence of bottom shape in the pipe wall thinning inspection using an electromagnetic acoustic resonance method
著者:
浦山 良一 Ryoichi URAYAMA ジョン マンチョル Jeong Man Chul 原 翔一郎 Syoichiro HARA 高木 敏行 Toshiyuki TAKAGI 内一 哲哉 Tetsuya UCHIMOTO 丹治 和宏 Kazuhiro TANJI
発刊日:
公開日:
electromagnetic acoustic resonancepipe wall thinningthickness measurement
概要
Electromagnetic acoustic transducer (EMAT) provides non-contacting measurements and is often applied to monitoring in high temperature environment. Electromagnetic acoustic resonance method (EMAR) is transmits an ultrasonic burst wave, and the driving frequency of bust wave is swept. Then signal amplitude of each frequency is computed by the superheterodyne processing at the interval. Pulse-EMAR method is transmits an ultrasonic pulse wave propagating, but the pulse wave is not swept. Then echo waves received is anal ed by Fast Fourier Transform. Finally, the superposition of the nth compression (SNC) for data processing is applied to evaluate wall thickness for two methods. In this study, the influence of bottom shapes is evaluated using EMAR method and Pulse-EMAR method. nd therefore the specimens of three types which are with inclined bottom, R shape and scale-like shape are prepared. Influence of bottom shape appears as an attenuating of peak value of SNC, a widening of the full width at half maximum, and peaks of multiple.
