NDTsi 2001 Session: Major Component Inspection I-IV
Steam Generator Tube Inspection with Intelligent ECT System
K. Sawaragi, S.Tanioka ,Y.Asada, M. Kurokawa, K. Kawata, N.Kawase, Mitsubishi Heavy Industries, Japan
ABSTRACT
Steam generator tube inspection has demanding requirement of high detectability and high- speed inspection. To materialise both requirements Intelligent ECT system has been developed. The combination of 24 channels inclined lay out drive coils and thin film pick-up coils provide both high detectability, which is equivalent to rotating coil ECT, and high-speed inspection which is equivalent to conventional bobbin coil ECT. And the built-in electronic circuit materialises high S/N ratio. Intelligent ECT system which consist of Intelligent Probe, data acquisition unit and data analysis system was developed in 1997. The basic function was verified by first field trial in 1997. Various efforts have been made to improve the detectability, probe durability, automatic data analysis and flaw sizing technique. As the result of improvement, Intelligent ECT system is becoming the high system of completeness for field inspection. The mock-up testing has been done to check the performance of Intelligent ECT system at Argonne National Laboratory SG Mock-up in 2001. This SG mock-up facility contains 400 tubes. Test tube can be flaw free or contain OD or ID SCC, IGA, Fatigue cracks, wastage, or machined defects of several types. In this time the number of tested tubes is 167 tubes of 400 tubes. This paper describes the features of Intelligent ECT system, improvement of Intelligent ECT system and experience of Argonne National Laboratory SG Mock-up.
Publication Source: 3nd International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurized Components, November 14-16, 2001, Seville Spain. Publisher: Tecnatom s.a. - [Homepage]
