Field application of Equipotential Switching Direct Current Potential Drop Technique

Authors : Ji Hak Kim¹, Kyung Ha Ryu¹,
                 Il Soon Hwang¹

Company : ¹ Department of Nuclear Engineering
                     Nuclear Materials Laboratory
                     Seoul National University           
Country : Republic of Korea

Topic :

Non-Destructive Examination methods

ABSTRACT :

Flow Accelerated Corrosion (FAC) accident repeatedly occurred during power reactor operation worldwide and it is a major concern to the structural integrity. In case of Korea, failures due to FAC were not serious so far, but FAC problem could not be ruled out. Extensive amount of time is required for inspection of components that is susceptible to FAC.

An equipotential switching direct current potential drop (ES-DCPD) method was developed to screen the wall loss of piping. This method covers all ultrasonic technique (UT) inspection points of elbow components at once time. An ES-DCPD screening criterion is developed for screening the piping wall loss. It is calculated by Finite Elements Method (FEM) analysis reflecting 113 inspection data. To apply this method to nuclear power plants, hardware and software of existing equipment was improved. ES-DCPD method will be applied to Ulchin nuclear power plant at the early of April 2010.

Speaker Biographical Information

Ji Hak Kim is from Seoul National University in republic of Korea. He is getting a master's in nuclear materials engineering. He is writing his master's thesis under the guidance of Professor Il Soon Hwang. And he will go on for a doctorate next semester.

He is carrying out a study of non-destructive examination methods for Flow Acceleration Corrosion (FAC), especially Equipotential Switching Direct Current Potential Drop (ES-DCPD).