Nondestructive Evaluation for Duplex Stainless Steel Tube Using Multi-Frequencies Remote Field Testing

Abstract:

This paper presents the determination of Remote Field Testing (RFT) frequencies to accomplish the inspection of duplex stainless steel tubes grade ASME/ASTM SA 789. The tube specimen was 25.4 mm of outside diameter, and thickness of 1.65 mm with the different artificial flaws. A dual-pickup coils type of RFT probe was employed to inspect the specimen by inserting a probe within the tube. Optimum of testing frequency Range was determined based on an eddy current through transmission generation to produce different magnetic field density. RFT inspection frequency range for duplex stainless steel was consequently determined from 5 to 25 kHz which was different than those inspection frequencies of general ferromagnetic steel tube. In the experiment, calculated frequencies were then generated to the Eddy current (ET) and RFT probes for detecting the flaws of the tube specimen. The inspection signals were specifically shown in function of impedance plane to identify the flaw characters. The results showed that the RFT can be utilized to quantify the wall loss levels of duplex stainless-steel tube better than the ET. Especially, phase angle of inspection signals can be used to evaluate the different depths of the wall losses. Sensitivity of RFT showed the detection performance at minimum 20% of tube wall loss.

• Periodical: Key Engineering Materials (Volume 659)
• Pages: 633-637
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.659.633
• Online since: August 2015
• Authors: Cherdpong Jomdecha*, Isaratat Phung-On, Kasemsak Sritarathorn
• Keywords: Duplex Stainless Steel, Multi-Frequencies, Remote Field Testing, Tube

References

[1] S. Thirunavukkarasu, B.P.C. Rao, S. Vaidyanathan, T. Jayakumar, B. Raj. Influence of sodium deposits in steam generator tubes on remote field eddy current signals, INT. J. PRES. VES. PIP. 85 (2008) 211–218.

DOI: 10.1016/j.ijpvp.2007.10.010

[2] E. Brain, Materials Compensation Technique for Remote Field Technology users, The 3rd International conference CANDU in-serviced inspection and NDT (2010).

[3] B. Yang, X. Li, Pulsed remote field technique used for nondestructive inspection of ferromagnetic tube, NDT. & E. Int. 53 (2013) 47–52.

DOI: 10.1016/j.ndteint.2009.01.015

[4] M. Bohacova, Detection of imperfections on internal surface of super-duplex stainless steel tubes designated for oil and gas exploration by means of eddy current, 11th European Conference on Non-Destructive Testing (2014).

[5] K. Reber, A. Bönisch, Inspection of unusual Pipe Types with Eddy Current Technologies, The Pigging Products and Services Association seminar (2010).

[6] P. O. Moore, nondestructive Testing Handbook: Electromagnetic Testing, Vol. 5, third edition, American Society for Non-Destructive Testing , (2004).

[7] ASTM E2096/E2096M, Standard Practice for In Situ Examination of Ferromagnetic Heat-Exchanger Tubes Using Remote Field Testing, (2010).

DOI: 10.1520/e2096_e2096m-10