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http://dx.doi.org/10.6110/KJACR.2015.27.3.174

Characteristic Analysis of Electromagnetic-ultrasonic Guided Waves for Defect Signals in Condenser Tubes  

Choi, Sang-Hoon (Technical Research and Development Institute, KPS)
Wang, Gi-Nam (Department of Industrial Engineering, Ajou University)
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.27, no.3, 2015 , pp. 174-178 More about this Journal
Abstract
This paper describes a signal processing technique for identifying signals from defects by using an electromagnetic-ultrasonic guided waves method based on a magnetostrictive sensor that generates a torsional mode (T(0, 1)). Because this technique is based on the digital filtering, the filtered signals provide information on the relationship between the cutoff frequency of band-pass filter and the characteristic of defect signals in heat exchange tubes. To verify the performance of the technique, artificial defects with various thickness reduction ration and shape were machined in titanium tubes, and digital filtering results are reported. The results show that digital filtering provides information to the identify shape of defects and the contact condition between the tube and support ring. Therefore, the proposed technique has good potential as a tool for evaluating the integrity of heat exchange tubes.
Keywords
Guided Wave; Condenser Tube; Magnetostrictive Sensor; Frequency;
Citations & Related Records
Times Cited By KSCI : 5  (Citation Analysis)
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1 Rose, J. L., Jiao, D., and Spanner, Jr. J., 1996, Ultrasonic Guided wave NDE for Piping, Materials Evaluation, Vol. 54, No. 11, pp. 1310-1313.
2 Shin, H. J., Rose, J. L., and Song, S. J., 2000, Inspection of Heat Exchanger Tubing Detects with Ultrasonic Guided Waves, J. KSNT, Vol. 20, No. 1, pp. 1-9.
3 Park, I. K., Kim, Y. K., Kim, H. M., Song, W. J., Cho, Y. S., and Ahn, Y. S., 2005, Long Range Ultrasonic Guided Wave Techniques for Inspection of Pipes, J. KWS, Vol. 23, No. 5, pp. 43-48.
4 Choi, B. I., Cho, Y. H., Lee, J. H., and Shin, D. C., 2009, A Study on MsS Guided Wave Scattering from Defects, J. KSNT, Vol. 29, No. 5, pp. 442-449.
5 Cheong, Y. M., 2009, Experimental Evidence and Analysis of a Mode Conversion of Guided Wave Using Magnetostrictive Strip Transducer, J. KSNT, Vol. 29, No. 2, pp. 93-97.
6 Gil, D. S., Ahn, Y. S., Jung, G. J., and Kim, Y. G., 2012, Study on the Property of Guided Wave Signal Analysis according to Defect Shape of Small Size", J. KSNT, Vol. 32, No. 4, pp. 410-417.
7 Kim, Y. K., Park, I. K., Park, S. J., Ahn, Y. S., and Gil, D. S., 2012, A Technique for Defect Detection of Condenser Tube in Support Plate Region using Guided wave, J. KWS, Vol. 30, No. 6, pp. 522-527.
8 Gazis, D. C., 1959, Three-Dimensional Investigation of the Propagation of Waves in Hollow Circular Cylinders. I. Analytical Foundation, J. Acous. Soc. Am, Vol. 31, No. 5, pp. 568-573.   DOI