Development of Dissimilar Metal Weld Performance Demonstration System

In the early 1980s, many leaks in the piping systems of boiling water reactors in the USA were discovered in piping weld area which had been examined ultrasonically and found to be defect free. To enhance the reliability of ultrasonic testing system, ASME B and PV code section XI adopted the performance demonstration requirements (Appendix VIII) for the ultrasonic examination of nuclear power plant piping weld in the 1989 winter addenda for the first time. MOST Bulletin 2004-13 was published at 2004.6. Following the MEST Bulletin 2009-37 which was published at 2009.9(formerly MOST Bulletin 2004-13), all nuclear power plants in Korea shall implement performance demonstration of dissimilar metal weld. The object of this study is to develop the performance demonstration system for dissimilar metal weld ultrasonic testing of nuclear power plant in order to meet ASME Sec. XI Appendix VIII requirements and MEST Bulletin 2009-37. This paper describes the status of the development of dissimilar metal weld performance demonstration system in Korea