A New Eddy Current 3-D Profilometry for a Quantitative Measurement of Geometric Anomaly in Steam Generator Tubes of Nuclear Power Plants

Abstract:

Most of the corrosive degradations in steam generator tubes of nuclear power plants are closely related to the residual stress existing in the local region of a geometric change, that is, an expansion transition, u-bend, ding, dent, bulge, etc. Therefore, accurate information on a geometric anomaly in a tube is a prerequisite to the activity of a non destructive inspection for a precise and earlier detection of a defect in order to prevent a failure during an operation, and also for a root cause analysis of a failure. In this paper, a newly developed eddy current technique of a three-dimensional profilometry is introduced and the proof for the applicability of the technique to a plant inspection is provided. The quantitative profile measurement using a new eddy current probe was performed on steam generator expansion mock-up tubes with various geometric anomalies typically observed in the operating power plants, and the accuracy of the measured data was compared with those from the laser profilometry.

• Periodical: Key Engineering Materials (Volumes 321-323)
• Pages: 426-429
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.321-323.426
• Online since: October 2006
• Authors: Deok Hyun Lee, Myung Sik Choi, Do Haeng Hur, Jung Ho Han, Myung Ho Song, Un Chul Lee
• Keywords: Eddy Current, Geometric Anomaly, Profilometry, Steam Generator Tube

References

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