Papers by Author: Yong Sik Kim

Abstract: The ASME B&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. Korea Electric Power Research Institute(KEPRI) and Korea Hydro and Nuclear Power Company(KHNP) finished developing Korean Performance Demonstration(KPD) system for the ultrasonic examination to apply pressurized light-water and pressurized heavy-water reactor power plants piping weld in accordance with ASME code section XI, appendix VIII on January 2004. KEPRI has been accomplishing the performance demonstration for nuclear power plant piping weld ultrasonic examination in Korea from April 2004. This paper describes the implementation status of the performance demonstration for nuclear power plant piping weld ultrasonic examination in Korea.

Abstract:
The results of ultrasonic testing performed during in-service inspection period for main components of nuclear power plant are affected by the performance of each inspector. To enhance the inspection reliability, the more restrictive qualification is required. KEPRI established Korean performance demonstration (KPD) system for the ultrasonic testing personnel, equipment and procedure which applied to the piping examination of nuclear power plant. A round robin test was conducted to evaluate the reliability of examination result by comparing conventional (DAC) UT and performance demonstration (PD) UT method. Participants took detection/length sizing test and depth sizing test using DAC method and PD method. The results showed that the PD method was preciser and more accurate than the conventional DAC method in length and depth sizing regardless of field experience and PD qualification status.