Failure Analysis of Cracked and Corroded Tubings in Sudong Block of Changqing Oilfield

Abstract:

In the process of layer inspection and hole mending, it was found that the corrosion of tubing in a well was serious, and perforation and fracture occurred. Part of the tubing was found to be cracked from the failed pipe samples, and relatively serious pitting corrosion pits were found on the surface of the outer wall. The fracture morphology and corrosion products were analyzed by means of macroscopic analysis and metallographic microscope, SEM and EDS. The result show that the mechanical damage of the outer wall of the tubing was the primary condition for accelerating corrosion, and the severe corrosion thinning of the inner and outer walls of the tubing was the main reason for the failure of the tubing string. The corrosion perforation of tubing was mainly caused by internal corrosion.

• Periodical: Materials Science Forum (Volume 1035)
• Pages: 638-646
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1035.638
• Online since: June 2021
• Authors: Xue Hui Zhao*, Ming Xing Li, Jun Lin Liu, Man Liu
• Keywords: Damage, Failure Analysis, Pitting, Tubing

References

[1] Feng Yaorong, Fu Anqing, Wang Jiandong, et al. Research progress and prospect of failure control and integrity technology of oil casing string in complex working conditions [J].The natural gas industry, 2020, 40(2): 106-114.

[2] Lv Shuanlu, LI Helin, Teng Xueqing. et al. Summarizing of Failure Analysis on Tubing and Casing Galling and Leakage[J]. OIL FIELD EQUIPMENT, 2011, 40(4): 21-25.

[3] Wang Shaolin, Fei Jingyin,Lin Xihua, et al. Research progress of high performance corrosion resistant pipe and super 13Cr[J]. Corrosion Science and Protection Technology, 2013, 25(4): 322-326.

[4] Yuan Yue, Zhang Jiangjiang, Guo Yujie, et al. Analysis on Finite element of residual strength of the oil pipe with uniform corrosion defects[J].New technology and New process, 2020, 4: 60-66.

[5] Lin Naiming, Xie Faqin, Wu Xiangqing, et al. Research status and prospect of oil casing surface protection technology [J]. Corrosion and Protection, 2009, 30(11): 801-805.

[6] Han yan, Ji rui, Lv yuhai, et al. Failure analysis of corrosion perforation of a N80S tubing [J]. Corrosion and Protection, 2019, 40(12): 933-937.

[7] Liu Zongzhao, Wang Yu, Wang Jun. Research on Corrosion Behavior of Release Sewage of Acidizing in the Exploration of LD10-1 Oilfield[J]. TOTAL CORROSION CONTROL, 2013, 27(6): 35-39.

[8] Li Wenfei, Xia Wenan. Numerical Simulation Analysis on Corroded Casing Residual Strength[J]. NATURAL GAS AND OIL, 2013, 31(6): 70-75.

[9] Shi Hongyan. Hole-type Corrosion Damage Pipelines Residual Strength Evaluation[J]. Pipeline Technique and Equipment, 2017, 1: 47-50.