EVALUATION OF WELD DEFECT SIGNAL FEATURES USING ULTRASONIC FULL WAVE PULSE ECHO METHOD

Abstract

Inspecting weld structures is crucial to determine the quality of welds to prevent failure in daily operations. Ultrasonic testing (UT) is an effective and non-destructive test that has become one of the most suitable methods for detecting defects in welded structures. This work presents a method to determine the most suitable feature extraction using full-wave pulse echo (FWPE) to distinguish the various types of weld defects in single V-joint plates. Six types of certified carbon steel welding materials with induced defects are employed in this study. Normal condition welding (no defects) is used as a reference. A portable ultrasonic equipment generates the FWPE signal using a shear wave angle beam probe. The measured FWPE signals in the configured scanning area are filtered to reduce noise and subsequently recorded to extract the wave characteristics. Manual transverse scan probe movement is performed in the defect areas on both sides of the weld for each welding specimen to obtain the B-scan results. The outcomes revealed that characteristic extraction for the time domain, maximum amplitude, depth, number of peaks and skew can be used to determine the type of defect on the welded specimens tested. Scanning both sides of the weld provides additional information that helps distinguish the type of defect in terms of orientation and position.
Keywords: Ultrasonic testing (UT); full-wave pulse echo (FWPE); weld defects; signal features extraction; transverse scan probe movement

Description