Acoustic Emission Technique for Damage Assessment of Gas Pipeline in Hydraulic Test

Inspection of oil and gas pipelines for integrity assessment is usually carried out by ILI (in-line inspections) tools (pigs). In case a pipeline section cannot be inspected by pig other methods should be considered. Among these, acoustic emission is a promising NDT technique allowing monitoring of structures in service condition. As challenging task of the eni R&D project a 48” OD pilot pipeline, made up of API5L X80 steel grade pipes, has been designed and installed in CSM full scale laboratory located in Sardinia. On the outer surface of each pipe Dent & Gouge (D&G) defects have been machined, representing the Third Party Interference (TPI) damage. For about 18 months the line was operated in severe conditions in terms of cycling pressure and cathodic overprotection corresponding to a pipeline under service conditions. The nucleation and growth of cracks have been monitored by using acoustic emission (AE) technique during the campaign and supported periodically by NDT investigations. Finally, a hydraulic test was performed according to a procedure consisting of four steps characterized by increasing pressure ramps and subsequent hold time in which the pressure load has been kept. AE technique has localized and monitored the propagation of defects. In the crack areas metallographic analysis were also made.

1. Tiratsoo, J., ed. Pipeline pigging technology, Second Edition. 1999. 2. GE Energy Oil & Gas, Solution for unpiggable Pipelines. newsletter/july/wece/geog_wece_news/ GEOG_UNPIG.pdf. 3. Budano, S., A. Lucci, R. Piancaldini, L. Prandi and G. Giunta. “Damages Monitoring for OIL&GAS Pipeline using AT Technique,” Proc. 30th European Conference on Acoustic Emission Testing, University of Granada. September 2012. 4. Cosham, A., P. Hopkins. “The Effect of Dents in Pipeline – Guidance in the Pipeline Defect Assessment Manual,” Proceedings ICPVT, July 2003, Vienna, Austria. 5. Panetta, P.D., et al. Mechanical Damage Characterization in Pipelines. Pacific Northwest National Lab. Richland WASA35467. October 2001. 6. Budano, S., A. Lucci, R. Piancaldini, L. Prandi and G. Giunta. “Damages Monitoring for Oil and Gas Pipeline Using AE Technique,” EWGAE 2012, Granada, Spain. September 2012. 7. Jones, D.G. and P. Hopkins. “The Influence of Mechanical Damage on Transmission Pipeline Integrity,” Proc. 1983 Int. Gas Research Conference, London, June 1983. 8. Cialone, H.J., D.N. Williams and T.P. Groeneveld, “Investigation of the causes of Hydrogen-Related Failures at Mechanically Damaged Regions,” NG 18 Report No. 189. September 1991. 9. Giunta G., L. Prandi, S. Budano and A. Lucci. “Fracture Mechanisms Evaluation in Gas Transportation Pipes by Acoustic Emission Analysis,” ASNT Fall Conference and Quality Testing Show, October. 2011, Palm Springs, CA. 10. Giunta G., S. Budano, A. Lucci and L. Prandi. “Pipeline Health Integrity Monitoring (PHIM) Based on Acoustic Emission Technique,” ASME, Pressure Vessels & Piping Conference, July 2012, Toronto, PVP2012-78545. 11. ASME Code 2007 “Boiler & Pressure Vessel Code Section V NDT Examination,” Article 12 Acoustic Emission Examination of Metallic Vessels During Pressure Testing, pp. 201, 213. 12. De Lorenzo G. and G. Giunta. “Method for the elastic installation of detection devices on pipelines and suitable device therefore,” Patent PCT/EP2009/00297. 13. Giunta G., S. Budano, L. Prandi and A. Lucci. “Improvement of reliability assessment of gas pipeline using Acoustic Emission technique.” ASME, Pressure Vessels & Piping Conference, July 2013, Paris, PVP2013-97175. 14. Tracy, N., tech. ed., P.O. Moore, ed. ASNT Nondestructive Testing Handbook, third edition: Volume 6, Acoustic Emission Testing ASTM E569-13 Acoustic Emission Monitoring of Structures During Controlled Stimulation. 15. Budano S., G. Giunta and A. Lucci. “Acoustic Emission data analysis to evaluate damage mechanisms in pipeline carbon steels,” The e-Journal of Nondestructive Testing, Vol. 1, 2011 16. Budano S., G. Giunta and A. Lucci, “Damage Mechanism Evaluation in Pipeline Steels using Acoustic Emission Analysis,” The e-Journal of Nondestructive Testing, 2013-08
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