Corrosion Failure Analysis of a New L360 Pipeline

Abstract:

In this paper, the optical microscope, scanning electron microscope (SEM), X-ray Diffraction (XRD) and simulation test were utilized to study the corrosion failure of L360 pipeline. The results show that the corrosion pits distributed around the pipe inner surface. The pipe mechanical properties, chemical constituents and inclusions grade satisfied the requirements of the technical conditions. Inclusions were composed of Ca, S, Al and O. Corrosion products consisted of the Fe₃O₄, Fe₂O₃ and FeO (OH). The compositions of corrosion products within and around the pits were similar to the inclusions. Due to the combined effects of water and high pressure air sealed in the pipeline, the pits formed around inclusions, and developed into occluded cells which accelerating the corrosion and leading to the failure finally.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 930-936
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.930
• Online since: March 2016
• Authors: Xin Su, Feng Wang, Yu Ran Fan, Yan Chun Zhang, Qing Lai Chen
• Keywords: Corrosion Failure, Inclusions, L360 Pipe, Occluded Cell

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