Ultrasonic testing techniques for the binding quality of heat shrinkable tapes used in the field coating for welded joints of pipeline

This paper presents several ultrasonic techniques with different principles and processes to test the binding quality of heat shrinkable tapes used in the field coating for welded joints of pipeline and compares their advantages and disadvantages. A series of experiments are conducted on pulse-echo ultrasonic testing technique, and the evaluation methods for the binding quality of the heat shrinkable tapes used in the field coating for welded joints of pipeline based on ultrasonic testing are established. Moreover, the software and prototype device for evaluating the binding quality are developed and tested on the welded joint blocks. The results show high consistency with the results of mechanical stretch test. The proposed technique provides a new means for testing the binding quality of heat shrinkable tapes used in the field coatings for welded joints of pipeline.