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Journal of Failure Analysis and Prevention

, Volume 15, Issue 5, pp 604–611 | Cite as

Failure Analysis of Disbondment of Three-Layer Polyethylene Coatings from the Surface of Buried Steel Pipelines

Case History---Peer-Reviewed

Abstract

A failure analysis was conducted to analyze the mode and causes of the disbondment of the three-layer polyethylene coatings from the surface of buried steel pipelines. The failure interface was analyzed through visual and microscopy investigations. Analysis of the coating at the disbonded interface revealed that the fusion bonded epoxy (FBE) layer had a fragile integrity which may have resulted from the in-service conditions of the pipeline. According to failure analysis of the disbonded interface, it can be concluded that degradation of the molecular structure of FBE layer was the most probable cause of the coating failure. It is believed that degradation of the molecular structure of FBE layer and subsequent disbondment of the coatings was caused by a mechanical-assisted cathodic delamination process which was due to the simultaneous action of chemical degradation and residual stresses at the coating-substrate interface. It is believed that surface pretreatment of the steel substrate in addition to coating process parameters of the powder coating are the main parameters in determining the long-term performance of the coating-substrate interface and should be carefully controlled.

Keywords

Coating Failure analysis Three-layer polyethylene Disbondment 

References

  1. 1.
    J.M. Pommersheim, T. Nguyen, Degradation of organic coatings on steel: mathematical models and predictions. Prog. Org. Coat. 25, 23–41 (1994)CrossRefGoogle Scholar
  2. 2.
    G. Grundmeier, W. Schmidt, M. Stratmann, Corrosion protection by organic coatings: electrochemical mechanism and novel methods of investigation. Electrochim. Acta 45, 2515–2533 (2000)CrossRefGoogle Scholar
  3. 3.
    M.I. Karyakina, A.E. Kuzmak, Protection by organic coatings: criteria, testing methods and modelling. Prog. Org. Coat. 18, 325–388 (1990)CrossRefGoogle Scholar
  4. 4.
    G.P. Guidetti, G.L. Rigosi, R. Marzola, The use of polypropylene in pipeline coatings. Prog. Org. Coat. 27, 79–85 (1996)CrossRefGoogle Scholar
  5. 5.
    G.R. Howell, Y.F. Cheng, Characterization of high performance composite coating for the northern pipeline application. Prog. Org. Coat. 60, 148–152 (2007)CrossRefGoogle Scholar
  6. 6.
    Y. Joliff, L. Belec, E. Aragon, Influence of the thickness of pipeline coating on internal stresses during the manufacturing process by finite element analysis. Comput. Mater. Sci. 68, 342–349 (2013)CrossRefGoogle Scholar
  7. 7.
    E. Legghe, Y. Joliff, L. Belec, L. Aragon, A. Margaillan, Computational analysis of internal stresses generated during the manufacturing process of a monolayer or three-layer pipeline coating. Comput. Mater. Sci. 48, 360–365 (2010)CrossRefGoogle Scholar
  8. 8.
    E. Legghe, Y. Joliff, L. Belec, E. Aragon, Computational analysis of a three-layer pipeline coating: internal stresses generated during the manufacturing process. Comput. Mater. Sci. 50, 1533–1542 (2011)CrossRefGoogle Scholar
  9. 9.
    D. Melot, G. Paugam, M. Roche, Disbondments of Pipelines Coatings and Their Consequences on Corrosion Risks, 17th International Conference on Pipeline Protection, BHR Group, Edinburgh, 2007.Google Scholar
  10. 10.
    M. Roche, An Experience in Offshore Pipeline Coatings, Corrosion, 2004—NACE International, New Orleans, USA, 2004.Google Scholar
  11. 11.
    M. Roche, D. Melot, G. Paugam, Recent Experience with Pipeline Coating Failures, 16th International Conference on Pipeline Protection, BHR Group, Paphos, Cyprus, 2005.Google Scholar
  12. 12.
    M. Roche, External Coatings of Pipelines: Challenges Related to Corrosion Risks, Iranian Corrosion/2007—ICA International Congress, Tehran, 2007.Google Scholar
  13. 13.
    C. Argent, D. Norman, Three Layer Polyolefin Coatings: Fulfilling Their Potential? Corrosion 2006, 12–16 March, San Diego, California, USA, 2006Google Scholar
  14. 14.
    C. Argent, D. Norman, Fitness for Purpose Issues Relating to FBE and Three Layer PE Coatings, Corrosion 2005, 3–7 April, Houston, Texas, USA, 2005Google Scholar
  15. 15.
    H. Leidheiser, W. Wang, L. Igetoft, The mechanism for the cathodic delamination of organic coatings from a metal surface. Prog. Org. Coat. 11, 19–40 (1983)CrossRefGoogle Scholar
  16. 16.
    D. Roy, G.R. Simon, M. Forsyth, J. Marde, Modification of thermoplastic coatings for improved cathodic disbondment performance on a steel substrate: a study on failure mechanisms. Int. J. Adhes. Adhes. 22, 395–403 (2002)CrossRefGoogle Scholar
  17. 17.
    F.M. Song, N. Sridhar, Modeling pipeline crevice corrosion under a disbonded coating with or without cathodic protection under transient and steady state conditions. Corros. Sci. 50, 70–83 (2008)CrossRefGoogle Scholar

Copyright information

© ASM International 2015

Authors and Affiliations

  • Mansour Rahsepar
    • 1
  • Mohammad Asgharzadeh
    • 1
  • Mohammad Jafar Hadianfard
    • 1
  • Seyed Ahmad Jenabali Jahromi
    • 1
  1. 1.Department of Materials Science and Engineering, School of EngineeringShiraz UniversityShirazIran

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