Wavelet-based pipe flaw 2D-reconstruction scheme using line-focusing ultrasonic transducer array

This paper developed a single right angle line-focusing ultrasonic transducer array to detect all the dents, metal loss and crack-like flaws. By using the A-scan ultrasonic signals captured from the array, 2D images of the pipe flaws can be obtained, so the size and location of the flaw can clearly be got. In this paper, the algorithm for flaw 2D-reconstruction is presented. Meanwhile, a wavelet-based technology for the purpose of lessening the influence of noises and improving inspection accuracy is introduced. With this method, the flaw image can be of high accuracy from even heavy noised ultrasonic A-scan signals. Finally, experiments have been performed on a pipe specimen with standard flaws. The reconstructed results show the effectiveness and potential of this scheme in pipe flaw inspection.