FEM Analyses of the TOFD Technique in Unequal Thickness Component

Abstract

The time-of-flight diffraction (TOFD) technique is a new ultrasonic nondestructive testing method. It utilize the longitudinal diffraction signal that generated from the defects, we can confirm whether there is a discontinuity in butt weld by the analysis of diffracted waves. This detection method has wide application prospects and detect flaws with high precision of localization and quantification. In this paper, two-dimensional numerical simulation of ultrasonic TOFD technique is carried out on unequal thickness butt weld of Drum Cylinder and Spherical Head, the propagation characteristics and laws of ultrasonic wave in unequal thickness component are analyzed by using finite element software ABAQUS. The simulation results show that the ABAQUS software can effectively simulate ultrasonic TOFD technique in such pressure vessel component, so the application range of ultrasonic TOFD technique will be extended.