Comparative Testing of Radiographic Testing, Ultrasonic Testing and Phased Array Advanced Ultrasonic Testing Non Destructive Testing Techniques in Accordance with the AWS D1.5 Bridge Welding Code

摘要

A comprehensive body of non-destructive testing data was collected from steel bridge welds under real-world conditions in a fabricators shop. Three different non-destructive testing (NDT) techniques were used on each weld inspection, these being Radiographic Testing (RT), conventional Ultrasonic Testing (UT), and Phased Array Ultrasonic Testing (PAUT). These data were then compared to determine whether PAUT might in future be adopted under the American Welding Society (AWS) D1.5 code as a suitable substitute for the currently required RT. Rejection rates using PAUT were similar to those of RT and UT, thereby allaying concerns that the potentially more sensitive PAUT might result in unnecessary rejections. Although all three NDT techniques generally agreed, there were some rare exceptions. These occurred when edge flaws were present, resulting in a PAUT acceptance despite a RT rejection. Additional testing was performed on three custom-designed test plates with built-in edge flaws. These plates were inspected using a procedure that also included supplemental manual and raster scanning. Using this testing procedure the PAUT came into total agreement with RT and UT regarding all plate defects. It was concluded that PAUT would make a suitable substitute for RT (and UT) in bridge weld inspection, provided an appropriate procedure is followed. Considerable cost savings could be realized by making such a change.