Given the conditions of production corrosive activity growth on Vietsovpetro fields, a new approach has been implemented to safely operate the subsea pipelines. The main factors have been described, which mostly affect the corrosion processes and reduce the inhibitor protection efficiency of pipeline systems for oil gathering and transportation. To improve an operational lifetime of transport pipeline systems and reduce an incident rate, the «Comprehensive program on pipelines and equipment corrosion protection, inhibitor protection and corrosion monitoring at Vietsovpetro fields» have been developed. The article includes the main results and technical features of pipelines in-line cleaning and inspection on Vietsovpetro offshore facilities, as well as the subsea pipelines operating challenges and ways to resolve those. For initial cleaning of oil pipelines the polyurethane and foamed plastic pistons of various hardness degree have been used. The amount of sediments, obtained from cleaning averages 2,4 t/km. The material composition of the deposits is represented mainly by asphaltene-resin-paraffin components. Water pipelines have been cleaned from corrosion deposits and solids by a large-volume water flushing with a constant monitoring of flush water clarity. Use of elastic gel compositions for cleaning the gas pipelines from water enables not only to dry the pipeline, but also to avoid possible complications related to the complex geometry of the pipelines. For the first time ever, Vietsovpetro has developed and is implementing the comprehensive actions with the long-term perspective to reduce the risks of subsea pipelines failures, while the most works are carried out by the Company.
References
1. Savel’ev V.V., Chernyad’ev I.N., The corrosive activity of water produced from offshore oil fields of Vietsovpetro JV (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 1, pp. 54–56, DOI: https://doi.org/10.24887/0028-2448-2019-1-54-56
2. Savel’ev V.V., Ivanov A.N., Avdeev A.S. et al., Integrated solutions for improving the reliability of Vietsovpetro subsea oil pipelines (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, no. 2, pp. 106–110, DOI: https://doi.org/10.24887/0028-2448-2024-2-106-110
3. Lepikhin A.M., Makhutov N.A., Leshchenko V.V., Shmal’ G.I., Problems of safety of underwater pipelines (In Russ.), Morskaya nauka i tekhnika, 2022, no. 5,
pp. 32–37.
4. Faritov A.T., Khudyakova L.P., Rozhdestvenskiy Yu.G. et al., Effect of solids precipitation and deposition of corrosion products on the protective ability of inhibitors
(In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 6, pp. 116–121.
5. Strel’nikova K.O., Vagapov R.K., Zapevalov D.N. et al., Determination of protective aftereffect of corrosion inhibitors in presence of aggressive carbon dioxide in gas deposits (In Russ.), Korroziya: materialy, zashchita, 2020, no. 11, pp. 29–37.
6. Savel’ev V.V., Ivanov A.N., Chernyad’ev I.N., The inhibitor protection of gas-lift pipelines in Vietsovpetro JV (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020,
no. 5, pp. 68–71, DOI: https://doi.org/10.24887/0028-2448-2020-5-68-71
7. Qiuping Ma,Guiyun Tian,Yanli Zeng et al., Pipeline in-line inspection method, instrumentation and data management, Sensors, 2021, V. 21(11),
DOI: http://doi.org/10.3390/s21113862
8. Kichenko S.B., Kichenko A.B., On question of evaluation of complex effectiveness for corrosion inhibitors (In Russ.), Praktika protivokorrozionnoy zashchity, 2005,
no. 3, pp. 24–28.
