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Vol.5 No.2 previous AA 68-SP10(69-70-71)-NT 58 -59

Academic Articles
Regular Paper Vol.5No.3 (2013) p.155 - p.164

Online Monitoring of Pipe Wall Thinning by Electromagnetic Acoustic Resonance Method

Ryoichi URAYAMA1, Toshiyuki TAKAGI1*, Tetsuya UCHIMOTO1 and Shigeru KANEMOTO2
1Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
2School of Computer Science and Engineering, The University of Aizu, Japan
The electromagnetic acoustic resonance (EMAR) method provides accurate and stable evaluation in high temperature environment, and it is an effective tool for online monitoring. In this study, the EMAR method and the superposition of the n-th compression (SNC) for data processing are applied to online monitoring of pipe wall thinning, and the accuracy and reliability of the measurements are demonstrated through field tests using a large-scale corrosion test loop at high temperature. To measure the thickness of pipes with complicated wall thinning, the SNC extracts thickness information from the spectral responses of the EMAR. Results from monitoring test show that EMAR with SNC can evaluate pipe wall thinning with an accuracy of 10μm at 165ºC. In addition, time evaluation of evaluated thickness decreases monotonically all over the test duration, which indicates high stability of this measurement technique.
online monitoring, NDT, EMAR, pipe wall thinning, thickness measurement, signal processing.
Full Paper: PDF EJAM Vol.5No.3 pp.155-164 "Online Monitoring of Pipe Wall Thinning by Electromagnetic Acoustic Resonance Method"

Article Information
Article history:
Received 5 March 2013
Accepted 2 October 2013