Phased Array Inspection of Nozzle Welds on Pressure Vessels of High Thickness

The new technology of phased array(PA) ultrasonic inspection adopted by European countries, in accordance with the requirements of ASME Code Case 2235, used for the nozzle welded joints on pressure vessels of high thickness was introduced. The importance of calibration blocks，scanning devices and procedure qualification, and the advantages of PA being able to change beam angles freely and focusing dynamically were emphasized. Finally, the benefits and limitations of applying PA technology to resolve some of difficult problems on NDE of pressure equipments were pointed out.