Preliminary Results of a Pilot Study on ET Inspection Qualification of VVER Type SG Tubes Based on Blocks with Realistic SCC Defect Simulations
L. Horácek, Nuclear Research Institute, Czech Republic
ABSTRACT
A Pilot study on Eddy current inspection qualification of VVER 440 steam generator tubes, discussed in this paper, followed the ENIQ methodology principles and covered briefly the assumed scope of ET qualification, relevant elaborated qualification documents, known ISI limitations and a review of input information on component and defects determined for Eddy current inspection qualification of VVER 440 steam generator tubes. The information includes the fabrication of the test blocks with SG tube segments provided by intended defect simulations of realistic SCC type and basic data on the realistic SCC type defects manufacturing technology. Lessons learned from the development of manufacturing technology of SSC type of defects, regional blind tests, elaboration of the preliminary technical justification for Eddy current automated inspections, potential optimisation of inspection procedures, laboratory and practical open trials are summarised in the paper. The results of the Pilot study seems to be useful for practical operational ISI programme decisions and the establishment of plugging criteria of VVER 440 and VVER 1000 type steam generator tubes. The Pilot study results are assumed to be used for the national qualification of Eddy current automated inspections of steam generator tubes in the near future.
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]
