R&D of multi-frequency ECT algorithms for FBR SG tubes

Mihalache, O.; 山口 智彦; 白濱 卓馬; 上田 雅司

Proceedings of 3rd International Conference on Maintenance Science and Technology (ICMST 2016) (Internet), 2 Pages, 2016/11

The adherence of sodium on the external surface of steam generator tubes of Fast Breeder Reactors (FBR) adds an additional level of complexity in the in-service inspection (ISI) of SGs using eddy current testing (ECT). The paper focusses on research and development of novel multi-frequency algorithms, based on ECT, special developed and tuned to enhance the signal from defects located on external SG tube surface and to suppress electromagnetic noise from the conductive sodium and SG support plates. The application of the method is investigated using both three-dimensional finite element (FEM) simulations and experimental measurements from SG tubes soaked and then drained of sodium, in a sodium tank mock-up.