| Autor: |
ZHU Dajiang, FAN Yu, ZHANG Huali, LI Yufei, ZHANG Lin, SONG Yang |
| Jazyk: |
čínština |
| Rok vydání: |
2022 |
| Předmět: |
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| Zdroj: |
Cailiao Baohu, Vol 55, Iss 9, Pp 27-33 (2022) |
| Druh dokumentu: |
article |
| ISSN: |
1001-1560 |
| DOI: |
10.16577/j.issn.1001-1560.2022.0242 |
| Popis: |
Aiming at understanding the corrosion type, corrosion severity and corrosion resistance of downhole oil casing steel, scanning electron microscopy, energy dispersive spectrometer and metallographic microscope were utilized to investigate the corrosion morphology and products of 028 nickel - based alloy oil tubing and 140ksi carbon steel casing materials in the simulated downhole drilling fluid of a gas well. Additionally, the uniform corrosion of a single material and the galvanic corrosion behavior after the coupling of two materials were evaluated, and the influencing factors and corrosion mechanisms were analyzed. Results showed that under this simulation condition, the single corrosion and galvanic corrosion of 028 nickel - based alloy oil tubing were both extremely slight, and the corrosion resistance of such tubing was excellent. In contrast, the single corrosion and galvanic corrosion rates of 140ksi carbon steel casing were 0.210 6 mm/a and 1.528 3 mm/a respectively, which indicated severe corrosion and extremely severe corrosion respectively. It could be concluded that the existence of galvanic corrosion conditions aggravated the corrosion degree of carbon steel casing. Thus, when designing sour gas well tubing strings, the combination of tubing materials should be chosen based on the actual downhole working conditions and taking into account not only the anti - corrosion performance of single material but also the galvanic corrosion resulting from the coupling contact of various materials, so as to reduce or avoid galvanic corrosion. Moreover, effective anti - corrosion measures should be worked out for ensuring the long - term integrity of gas well tubing strings. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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