Application of Laser-Generated Ultrasound for Evaluation of Wall-thinning in Carbon Steel Elbow
نویسندگان
چکیده
The objective of this research is to estimate location and size using laser ultrasound guided wave for wall thinning evaluation of elbow. Wall thinning of carbon steel pipe is one of the most serious problems in Nuclear Power Plant especially wall thinning of carbon steel elbow caused by FAC (Flow-Accelerated Corrosion). Therefore non-destructive inspection method of elbow is essential for safe operation of nuclear power plants. Specimens used in this study were carbon steel elbows as the main elements of real nuclear power plants, and shape of wall thinning was an oval with 120mm-width, 80mm-length and 5mm-depth. The L(0,1) and L(0,2) modes variation of ultrasound guided wave from the response obtained by the laser generation/air-coupled detection ultrasonic hybrid system represent characteristics of the defect. The trends of these characteristics and signal processing used to estimate the size and location of wall thinning.
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