Ultrasonic Phased Array for the Circumferential Welds Safety Inspection of Urea Reactor

Due to the multi-layer thick wall structure and coarse grain materials of inside liner, the circumferential welds safety inspection of urea reactor is usually not easy. The paper analyzes the problems and difficulties of NDT techniques used for circumferential welds of urea reactor and overviews the theory and advanced point of UPA technology. Then two related test blocks (RB-2/20 and Austenitic stainless steel butt joint test block) with artificial defects are selected to simulate the outer and inner layer. Experiments by UPA are carried out on the test blocks and results are analyzed. It is proved that UPA is effective and efficient in solving the circumferential welds safety inspection.