Research on automatic flaw detection of pipeline girth weld by ultrasonic phased array system

An automatic ultrasonic phased array inspection system used for nondestructive testing (NDT) of pipeline girth weld is developed. The linear phased array transducer is optimized by numerical analysis based on a mathematical model. Then hardware and software designs of the system are presented, realizing dynamically focusing in the detection area. A series of technological difficulties are solved. Finally, an automatic flaw detection testing platform on pipeline girth weld is set up. Experimental results illustrate the transducer optimum design improves system performance and the system has good capabilities of ultrasonic transmitting and echo synthesis, greatly improving testing flexibility and testing speed whereas reducing the system´s volume and weight. It can be extended to inspect an object with rough surface or irregular structure in industrial NDT field.