Article Article
Blind Trial Validation of a Guided Wave Structural Health Monitoring System for Pipework

Guided wave permanently installed monitoring systems (PIMS) are potentially very attractive for ensuring the integrity of critical structures, particu-larly where access for frequent NDT is difficult, but their performance has not yet been satisfactorily validated. This paper presents the results of a blind trial of a guided wave PIMS system on an L-shaped 8 in. (0.2 m) diameter pipe section with an overall length of 10 m, a 1.5D bend, and a total of three butt welds. Readings were taken at 30 min intervals over a period of roughly 40 days while the pipe temperature was cycled between ambient temperature and 60 °C, during which six simulated corrosion discontinuities were introduced. The data was sent in batches to an evaluation team who had no knowledge of the discontinuity locations or the schedule for their introduction; they reported on the data before being given the next batch. A new independent component analysis (ICA) scheme was used to process the measurement data, and all the discontinuities were successfully located with no false calls. It was found that the detection sensitivity was about a factor of five better than that typically obtained in one-off guided wave tests. Permanently installed guided wave monitoring systems are therefore a very promising technology for monitoring critical infrastructure.


Alleyne, D.N., and P. Cawley, 1996, “The Excitation of Lamb Waves in Pipes Using Dry Coupled Piezoelectric Transducers,” Journal of Nonde-structive Evaluation, Vol. 15, No. 1, pp. 11–20.

Alleyne, D.N., B. Pavlakovic, M.J.S. Lowe, and P. Cawley, 2001, “Rapid Long-Range Inspection of Chemical Plant Pipework Using Guided Waves,” Insight, Vol. 43, No. 2, pp. 93–96.

Birch, S., and F. Baker, 2007, “Long-Range Guided-Wave Ultrasonics: A New Age in Pipeline Inspection,” AWS Inspection Trends, Vol. 10, No. 4, pp. 13–17.

Carandente, R., J. Ma, and P. Cawley, 2010, “The Scattering of the Funda-mental Torsional Mode from Axi-Symmetric Defects with Varying Depth Profile in Pipes,” The Journal of the Acoustical Society of America, Vol. 127, pp. 3440–3448.

Cawley, P., F.B. Cegla, and A. Galvagni, 2012, “Guided Waves for NDT and Permanently-Installed Monitoring,” Insight: Non-Destructive Testing and Condition Monitoring, Vol. 54, No. 11, pp. 594–601.

Cawley, P., F.B. Cegla, and M. Stone, 2013, “Corrosion Monitoring Strate-gies — Choice Between Area and Point Measurements,” Journal of Nonde-structive Evaluation, Vol. 32, No. 2, pp. 156–163.

Clarke, T., F. Simonetti, and P. Cawley, 2010, “Guided Wave Health Moni-toring of Complex Structures by Sparse Array Systems: Influence of Temperature Changes on Performance,” Journal of Sound and Vibration, Vol. 329, No. 12, pp. 2306–2322.

Croxford, A.J., J. Moll, P.D. Wilcox, and J.E. Michaels, 2010, “Efficient Temperature Compensation Strategies for Guided Wave Structural Health Monitoring,” Ultrasonics, Vol. 50, Nos. 4 and 5, pp. 517–528.

Demma, A., P. Cawley, M. Lowe, and A.G. Roosenbrand, 2003, “The Reflec-tion of the Fundamental Torsional Mode from Cracks and Notches in Pipes,” Journal of the Acoustical Society of America, Vol. 114, No. 2, pp. 611–625.

Demma, A., P. Cawley, M. Lowe, and B. Pavlakovic, 2005, “The Effect of Bends on the Propagation of Guided Waves in Pipes,” Journal of Pressure Vessel Technology, Vol. 127, No. 3, pp. 328–35.

Dobson, J., and P. Cawley, 2016, “Independent Component Analysis for Improved Defect Detection in Guided Wave Monitoring,” Proceedings of the IEEE, Vol. 104, No. 8, pp. 1620-1631.

Harley, Joel B., and José M.F. Moura, 2012, “Scale Transform Signal Processing for Optimal Ultrasonic Temperature Compensation,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 59, No. 10, pp. 2226–2236.

Heinlein, S., P. Cawley, and T.K. Vogt, 2018, “Reflection of Torsional T (0,1) Guided Waves from Defects in Pipe Bends,” NDT & E International, Vol. 93, No. 1, pp. 57–63.

Hyvärinen, A. 1999, “Fast and Robust Fixed-Point Algorithm for Inde-pendent Component Analysis,” IEEE Transactions on Neural Networks and Learning Systems, Vol. 10, No. 3, pp. 626–634.

Hyvärinen, A., and E. Oja, 2000, “Independent Component Analysis: Algo-rithms and Applications,” Neural Networks, Vol. 13, Nos. 4–5, pp. 411–430.

Kwun, H., and C. Dynes, 1998, “Long-Range Guided Wave Inspection of Pipe Using the Magnetostrictive Sensor Technology: The Feasibility of Defect Characterization,” Proceedings of SPIE on Nondestructive Evaluation of Utilities and Pipelines II, Vol. 3398, pp. 28–34.

Ledesma, V.M.N., E.P. Baruch, A. Demma, and M.J.S. Lowe, 2009, “Guided Wave Testing of an Immersed Gas Pipeline,” Materials Evaluation, Vol. 67, No. 2, pp. 102–115.

Liu, C., J. Dobson, and P. Cawley, 2017, “Efficient Generation of Receiver Operating Characteristics for the Evaluation of Damage Detection in Practical Structural Health Monitoring Applications,” Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 473, No. 2199, DOI: 10.1098/rspa.2016.0736.

Rose, J.L., 2014, Ultrasonic Guided Waves in Solid Media, Cambridge University Press, Cambridge, England.

Usher, K.M., A.H. Kaksonen, I. Cole, and D. Marney, 2014, “Critical Review: Microbially Influenced Corrosion of Buried Carbon Steel Pipes,” International Biodeterioration & Biodegradation, Vol. 93, pp. 84–106.

Vinogradov, S.A., 2009, “Magnetostrictive Transducer for Torsional Guided Waves in Pipes and Plates,” Materials Evaluation, Vol. 67, No. 3, pp. 333–341.

Usage Shares
Total Views
421 Page Views
Total Shares
0 Tweets
0 PDF Downloads
0 Facebook Shares
Total Usage