Development of Ultrasonic Phased Array Probe for SAW Seam Inspection of UOE Pipe

Abstract

The requirements of Ultrasonic Testing, such as DNV, ISO specification etc., for longitudinal submerged arc weld (SAW) seam of UOE pipe become severe to the offshore steel line-pipe with high grade and heavy wall thickness. In order to satisfy the requirements, testing method with multi-probe arrangement have been widely applied in the pipe manufacture. Recently, the phased array technique has been applied for inspection of girth welds of pipeline and longitudinal ERW (electric resistance welded) seam instead of multi-probe method. But the inspection system with conventional phased array probe has many difficulty to apply for inspection longitudinal SAW seam of UOE pipe, because of defect detection capabilities, array elements arrangement, and so on. The authors have developed an applicable ultrasonic phased array probe to satisfy the severe requirements for longitudinal SAW seam of UOE pipe. This paper presents the results of our original designed array probe, which has been composed of 32-transducer elements mounted on cylindrical-shaped plastics, and also compares the inspection results to those obtained on the conventional multi-probe and our developed array probe in the UOE pipe mill.