Guided waves Evaluation of pipe defect using low-frequency shear wave transducers

This presentation addresses the challenge of inspecting carbon steel pipes along their entire length, particularly under limited access conditions. We propose a non-destructive evaluation (NDE) method utilizing shear-horizontal wave transducers for ultrasonic-guided wave generation. This proposed testing setup enables long-range pipe inspection from a single test location, even when access and clearance are limited, and allows for long-term monitoring. Preliminary numerical and experimental analyses were conducted on two carbon steel straight pipes, both with and without defects, using Guided Wave Ultrasonic Testing (GWUT). Digital signal processing algorithms were applied to improve the accuracy of defect detection. Additionally, the dispersion characteristics were considered over a range of frequencies. Numerical simulations were performed to investigate the mode cancellation effect using the current transducer array configuration. The results indicate that although four transducers are capable of generating the guided torsional mode, they are insufficient to excite the mode with adequate strength. Damping ratios and phase velocities were extracted from both simulations and experiments. Overall, this study demonstrates the effectiveness of shear-horizontal wave transducers in improving the accuracy and efficiency of guided wave-based NDE, offering promising applications for pipe inspection.