Defect Localization for Pressure Vessel Based on Circumferential Guided Waves: An Experimental Study

Pressure vessels are normally employed under extreme environments with high temperature and high pressure. Inevitably, the defects like crack and corrosion that easily occur in the equipment and can significantly influence the normal operation. Guided wave-based method is a cost-effective means to measure the utility of pressure vessel. In this paper, finite element (FE) simulation is used to explore the propagation characteristics of circumferential guided waves in pressure vessel. Based on the propagation characteristics, the experiments with different configurations of piezoelectric transducers (PETs), which contain a sparse array and a dense array, have been conducted on pressure vessel respectively. Different imaging methods, including discrete ellipse imaging algorithm and probability damage imaging algorithm have been applied to locate the defect based on the configurations above. Furthermore, a multi-channel ultrasonic guided wave detection system has been set up for pressure vessel inspection. The experimental results show that the sparse array with the discrete ellipse imaging algorithm can locate the defect effectively. The imaging results based on probability damage imaging algorithm show that the dense array presents the better localization result.