The article provides an in-depth analysis of the forecasts and projections of three leading global analytical organizations: the OPEC Secretariat, the U.S. Energy Information Administration (EIA), and the International Energy Agency (IEA). Despite the transformation of the energy landscape, the fragmentation of the global economy and the entire system of international relations, as well as geopolitical uncertainty and the rise of trade barriers, these organizations predict a steady increase in oil demand in 2026-2027, which will be largely driven by continued robust economic activity in the countries outside the Organisation for Economic Co-operation and Development (OECD). These countries will also contribute to the increase in demand, while demand in OECD countries will increase much less. The main drivers of the increase in oil demand in 2026-2027, as well as global economic growth, are the developing countries of Asia, led by China and India, and the continued economic growth in major developing economies. The key factors contributing to the global increase in oil demand are identified. The article also shows that during 2025 and the first two months of 2026, all three organizations have repeatedly revised their estimates of global oil demand for the current year and their forecast for 2026-2027. The analysis of these forecasts reveals that the estimates made by different agencies differ, although the differences are not significant. However, there are larger differences in regional estimates.

References

1. Net Zero by 2050. A Roadmap for the Global Energy Sector, URL: https://www.iea.org/reports/net-zero-by-2050

2. No new oil, gas or coal development if world is to reach net zero by 2050, says world energy body,

URL: https://www.theguardian.com/environment/2021/may/18/no-new-investment-in-fossil-fuels-demands-top-en...

3. Energy groups must stop new oil and gas projects to reach net zero by 2050, IEA says, URL: https://www.ft.com/content/2bf04fff-5b2f-4d96-a4ea-ff55e029f18e

4. Mastepanov A.M., Will oil remain the leading energy carrier in the world: At the crossroads of opinions (In Russ.), Problemy ekonomiki i upravleniya neftegazovym kompleksom, 2024, No. 5(233), pp. 5–7.

5. OPEC. Monthly Oil Market Report – 16 June 2025, URL: https://momr.opec.org/pdf-download/

6. Mastepanov A.M., Prospects for the development of the oil sector of the global economy in 2025-2026 in the assessments of leading foreign research centers

(In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2025, No. 9, pp. 6–12, DOI: https://doi.org/10.24887/0028-2448-2025-9-6-12

7. OPEC. Monthly Oil Market Report – 12 August 2025, URL: https://www.opec.org/assets/assetdb/momr-august-2025.pdf

8. OPEC. Monthly Oil Market Report – 14 January 2026, URL: https://www.opec.org/assets/assetdb/momr-january-2026.pdf

9. U.S. Energy Information Administration, Short-Term Energy Outlook, August 2025, URL: https://www.eia.gov/outlooks/steo/

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11. Mastepanov A.M., Prospects for the development of the global economy and its oil sector in 2025-2027 in the assessments of leading foreign research centers (In Russ.), Energeticheskaya politika, 2025, No. 9(212), pp. 24–49, DOI: https://doi.org/10.46920/2409-5516_2025_09212_24

12. Oil Market Report – December 2025, URL: https://www.iea.org/reports/oil-market-report-december-2025

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15. IEF. Monthly Comparative Analysis. January 2026, URL: https://www.ief.org/data/comparative-analysis

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17. Commodity Markets Outlook: October 2025, URL: https://openknowledge.worldbank.org/server/api/core/bitstreams/c579e19c-83a7-4d94-abda-77e4810b4ea4/content

As oil and gas exploration depths increase, rock compaction occurs, altering the reservoir structure, the volume of carbonate and crystalline rocks increases. The structure of tight rock deposits, particularly in basement formations, is characterized by significant heterogeneity in the composition and petrophysical properties of the rocks, and uneven distribution of decompressed reservoir rocks within the section. This article presents the summary results of the application and prospects of using modern research methods and approaches to studying the structure of oil and gas deposits in tight rock, predicting reservoirs within crystalline and carbonate deposits, and assessing their fracturing and cavernosity. A systems approach to evaluating geological and geophysical data was used to address these challenges. Modern «scattered wave» technology was used in the processing and interpretation of seismic data obtained by the 3D common depth point method, enabling the prediction of decompressed rock zones in the section based on elevated local energy attribute values. Using «seismic imaging» technology, the trap type is predicted based on seismic characteristics. Applying optical core analysis methods (with a scanning microscope) enables the identification of micro- and macrofractures in the rock, the sizes of identified caverns and microfractures, and the establishment of metasomatic zoning of hydrothermally altered rocks, thereby creating a detailed geological model of the reservoir. Joint research of OGRI of the RAS along with Gazpromneft and Rosneft companies using seismic research methods, core analysis, and well logging data enabled refinement of geological models of oil deposits in carbonate sediments and identification of promising targets.

References

1. Dmitrievskiy A.N., Kireev F.A., Bochko R.A., Kireeva T.A., On a new type of reservoir in crystalline basement rocks (In Russ.), DAN, 1990, V. 315, No. 1, pp. 163–165.

2. Dmitrievskiy A.N., Kireev F.A., Bochko R.A. et al., Magmatic-sedimentary formation complex as a new oil-promising object (In Russ.), DAN, 1992, V. 322, No. 2,

pp. 347–350.

3. Shuster V.L., Crystalline basement rocks are a promising target for increasing oil and gas reserves in Russia (In Russ.), Geologiya nefti i gaza, 1994, No. 9, pp. 35–38.

4. Shuster V.L., Oil and gas potential of the crystalline basement (In Russ.), Geologiya nefti i gaza, 1997, No. 8, pp. 17–19.

5. Patent RU2168187C1. Method of seismic prospecting in geological rock mass, Inventors: Levyant V.B., Mottl’ V.V.

6. Shuster V.L., Levyant V.B., Ellanskiy M.M., Neftegazonosnost’ fundamenta (problemy poiska i razvedki mestorozhdeniy uglevodorodov) (Oil and gas potential of the basement (Problems of prospecting and exploration of hydrocarbon deposits)), Moscow: Tekhnika Publ., 2003, 176 p.

7. Levyant V.B., Shuster V.L., Isolation in the foundation zone of fractured rock by seismic exploration 3D-methods (In Russ.), Geologiya nefti i gaza = The journal Oil and Gas Geology, 2002, No. 2, pp. 21–26.

8. Levyant V.B., Tronov Yu.A., Shuster V.L., Using the scattered component of the seismic field to differentiate the crystalline basement into reservoir and monolithic zones (In Russ.), Geofizika, 2003, No. 3, pp. 17–26.

9. Kur’yanov Yu.A., Kuznetsov V.I., Koshkakov V.Z., Smirnov Yu.M., Experience of using the field of scattered seismic waves for predicting fractured zones (In Russ.), Tekhnologiya seysmorazvedki, 2008, No. 1, pp. 25–31.

10. Shuster V.L., Takaev Yu.G., Mirovoy opyt izucheniya neftegazonosnosti kristallicheskogo fundamenta. Razvedochnaya geofizika: Obzor (Global experience in studying the oil and gas potential of crystalline basement reservoirs. Exploration geophysics: A review), Moscow: Geoinformmark Publ., 1997, 71 p.

11. Dmitrievskiy A.N., Shuster V.S., Punanova S.A., Doyurskiy kompleks Zapadnoy Sibiri – Novyy etazh neftegazonosnosti: Problemy poiskov, razvedki i osvoeniya mestorozhdeniy uglevodorodov (Pre-Jurassic complex of Western Siberia – A new level of oil and gas potential: Problems of prospecting, exploration, and development of hydrocarbon deposits), Saarbryuken: LAP LAMBERT Academic Publishing, 2012, 135 p.

12. Kurysheva N.K., Prognozirovanie, kartirovanie zalezhey nefti i gaza v verkhney chasti doyurskogo kompleksa po seysmologicheskim dannym v Shaimskom neftegazonosnom rayone i na prilegayushchikh uchastkakh (Forecasting and mapping of oil and gas deposits in the upper part of the pre-Jurassic complex based on seismological data in the Shaim oil and gas region and adjacent areas): thesis of candidate of geological and mineralogical science, Tyumen, 2005.

13. Shuster V.L., Punanova S.A., Kurysheva N.K., Novyy podkhod k otsenke neftegazonosnosti obrazovaniy fundamenta (A new approach to assessing the oil and gas potential of basement formations), Proceedings of international conference dedicated to the memory of V.E. Khain “Sovremennoe sostoyanie nauk o Zemle” (The current state of Earth sciences), Moscow: Publ. of Geological Faculty of MSU, 2011, pp. 2116–2118.

14. Tsimbalyuk Yu.A., Shpurov I.V., Matigorov A.A., Mul’tifokusing – innovatsionnaya tekhnologiya obrabotki dannykh seysmorazvedki (Multifocusing is an innovative technology for processing seismic data.), Proceedings of All-Russian scientific conference XI “Fundament, struktury obramleniya Zapadno-Sibirskogo basseyna” (Foundation and framing structures of the West Siberian Basin), Novosibirsk: Geo Publ., 2010, pp. 28–32.

15. Shaburova M.E., Orlov N.N., Allocation of improved filtration and reservoir properties zones using the example of an oil field in the Timan-Pechora oil and gas province (In Russ.), Ekspozitsiya Neft’ Gaz, 2024, No. 4(105), pp. 16–21, DOI: https://doi.org/10.24412/2076-6785-2024-4-16-21

16. Shaburova M.E., Shuster V.L., Allocation of seals and formations of dispersion according to a complex of geological and geophysical studies on the example of an oil field in the Timan-Pechora oil and gas province (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2025, No. 3, pp. 26–30, DOI: https://doi.org/10.24887/0028-2448-2025-3-26-30

17. Kutukova N.M., Shuster V.L., Modern methods for studying the heterogeneous structure of complex carbonate reservoirs and erosion protrusions of the foundation (In Russ.), Vestnik Moskovskogo universiteta. – Seriya 4: Geologiya = Moscow University Bulletin. Series 4. Geology, 2020, No. 6, pp. 88-94,

DOI: https://doi.org/10.33623/0579-9406-2020-6-88-94

18. Kutukova N.M., Volyanskaya V.V., Shuster V.L., Fault mapping methodology based on the intrusive bodies’ distribution: Baikit anteclise Vendian-Cambrian rock study (Siberian craton) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, No. 5, pp. 60-66, DOI: https://doi.org/10.24887/0028-2448-2021-5-60-66

Nowadays, fiber optic sensing systems are not widely used in Russia for vertical seismic profiling (VSP) and offset vertical seismic profiling (offset VSP) due to insufficient study of fiber optics capabilities. TATNEFT PJSC successfully completed offset vertical profiling in three wells using fiber optic systems. At the same time, vertical seismic profiling was performed in the same wells based on the conventional technology using electrodynamic receivers. During the well interventions, the following benefits were confirmed from using fiber optic sensing systems to record seismic wave fields in the wells based on the results of tying the obtained data to well logging and land seismic survey data: high speed of operations due to simultaneous recording along the entire wellbore with one seismic excitation at the array station; obtaining high-quality VSP survey data matching the data from SK6-823 logging tool. A number of problems were identified: a signal-to-noise ratio and a correlation coefficient are higher for offset VSP data obtained with the SK6-823 tool than that obtained with the fiber optic sensing system; the fiber optic sensing system performance reduces rapidly with the growing distance between a seismic source point and a well due to basic limitations of a uniform linear array related to its directivity parameters; a relatively high inherent noise level. Despite differences in the medium seismic response between a distributed sensor and geophones, the prospects of using fiber optic systems for VSP/ offset VSP are promising provided that their key drawbacks are eliminated.

References

1. Tabakov A.A., Stepchenkov Yu.A., Ferentsi V.N. et al., Wideband processing and interpretation of Vertical Seismic Profiling (VSP) data using High Definition Seismic (HDS) technology (In Russ.), Proceedings of 10th anniversary scientific and practical conference “Sankt-Peterburg 2023. Geonauki: vremya peremen, vremya perspektiv” (St. Petersburg 2023. Geosciences: A Time of Change, a Time of Prospects), 17-20 April 2023, St. Petersburg, Moscow: Publ. of Geomodel’, 2023, pp. 319–322.

2. Chugaev A.V., Tarantin M.V., Amplitude-frequency response of a helically-wound fiber distributed acoustic sensor (DAS) (In Russ.), Gornye nauki i tekhnologii, 2023, V. 8, No. 1, pp. 13–21, DOI: https://doi.org/10.17073/2500-0632-2022-06-10

3. Chugaev A.V., Kuznetsov A.I., Evaluation of the capabilities of distributed acoustic sensing with a helical fiber for cross-well seismic survey (In Russ.), Pribory i tekhnika eksperimenta = Instruments and Experimental Techniques, 2023, No. 5, pp. 167–173, DOI: https://doi.org/10.31857/S0032816223050087

4. Kharasov D.R., Spiridonov E.P., Naniy O.E. et al., DAS technology – Debunking myths and looking ahead (In Russ.), Pribory i sistemy razvedochnoy geofiziki, 2025, No. 2, pp. 24–33.

The paper considers active temperature logging as an efficient tool for diagnostics of well condition and environmental subsurface monitoring. This research is of current interest because most of oil and gas fields and underground gas storage facilities have a significant operation life. This leads to deterioration of wells technical conditions resulting in behind-the-casing flow and loss of casing integrity. The most insightful method for diagnosing the technical condition of wells is temperature logging; however it does not always enable the accurate detection of behind-the-casing flows. Innovative active temperature logging method that relies on induction heating of metal casing creates temperature disturbance. Its propagation and evolution are analyzed to identify behind-the-casing flows, casing leaks, and evaluate flow rates. Findings of the research conducted using advanced active temperature logging tools, including distributed temperature sensors, suggest that analysis of the speed, extent, and direction of generated temperature disturbance propagation enables not only determination of presence/ absence of behind-the-casing flows, but also identification of crossflow channels, flow rate, and reservoir injectivity, particularly for multilayer formations. The data obtained confirm that active temperature logging outperforms conventional diagnostic methods in terms of information content, which is important for development of oil and gas fields and protection of freshwater intervals.

References

1. Agadullin I.I., Ignat’ev V.N., Sukhorukov R.Yu., Environmental aspects of the leakage annulus in the wells for various purposes (In Russ.), Neftegazovoe delo, 2011,

No. 4, pp. 82–90.

2. Valiullin R.A., Yarullin R.K., Sharafutdinov R.F., Sadretdinov A.A., Present-day procedures of geophysical studies applied at the Russian fields (In Russ.), Neft’. Gaz.

Novatsii, 2014, No. 2(181), pp. 21-25.

3. Yarullin R.K., Yarullin A.R., Valiullin A.S. et al., Optimization of complex for horizontal wells production logging (In Russ.), Problemy sbora, podgotovki i transporta nefti i nefteproduktov, 2020, No. 4(126), pp. 19-28. – https://doi.org/10.17122/ntj-oil-2020-4-19-28

4. Sharafutdinov R.F., Valiullin R.A., Fedotov V.Ya. et al., Experience of using active temperature measurement technique in borehole status diagnostics (In Russ.), Karotazhnik, 2010, V. 193, No. 4, pp. 5–12.

5. Valiullin R.A., Sharafutdinov R.F., Ramazanov A.Sh., Shilov A.A., Enhancement of well productivity using a technique of high-frequency induction treatment,

SPE-157724-MS, 2012, DOI: https://doi.org/10.2118/157724-MS

6. Davletshin F.F., Ramazanov A.Sh., Akchurin R.Z. et al., Investigation of thermal field in a well under fluid movement under induction impact (In Russ.), Izvestiya Tomskogo politekhnicheskogo universiteta. Inzhiniring georesursov, 2023, V. 334, No. 3, pp. 153–164, DOI: https://doi.org/10.18799/24131830/2023/3/3896

7. Davletshin F.F., Islamov D.F., Khabirov T.R. et al., The study of heat exchange processes during induction heating of the casing string in relation to the determination of behind-the-casing flows (In Russ.), Vestnik Tyumenskogo gosudarstvennogo universiteta. Fiziko-matematicheskoe modelirovanie. Neft’, gaz, energetika, 2023, V. 9, No. 1, pp. 60–77, DOI: https://doi.org/10.21684/2411-7978-2023-9-1-60-77

8. Kosmylin D.V., Davletshin F.F., Islamov D.F. et al., Experimental study of the thermal field in the wellbore during induction (In Russ.), Neftegazovoe delo, 2023, V. 21, No. 2, pp. 56–64, DOI: https://doi.org/10.17122/ngdelo-2023-2-56-64

9. Valiullin R.A., Sharafutdinov R.F., Sorokan’ V.Yu., Shilov A.A., Experimental study of the thermal field in the wellbore during induction (In Russ.), Karotazhnik, 2002,

V. 100, pp. 124–137.

10. Patent RU2194160C2, Method of active temperature logging of operating wells, Inventors: Valiullin R.A., Sharafutdinov R.F., Ramazanov A.Sh., Dryagin V.V., Adiev Ya.R., Shilov A.A.

The paper examines methodological and practical aspects of building artificial intelligence (AI) systems aimed at reducing the impact of the human factor in knowledge-base construction and result interpretation. It is shown that current Russian state standards in the field of AI mainly regulate technical implementation principles while leaving the methodology for knowledge-base filling largely unaddressed, thereby increasing the risks of errors and vulnerabilities. As an alternative, the concept of objective intelligence (OI) is proposed  an approach based on the input of verifiable data, the use of validated regularities, and formalized rules. OI is implemented through an explicitly designed problem-solving model that includes a data input and validation module, a knowledge base, an inference engine, and a results interpretation module. The practical feasibility of the approach is demonstrated using the certified AutoCorr software, applied to construct objective geological models of structurally complex oil and gas-bearing formations. The main workflow stages are described: automated well-log correlation using weighted parameters of the logging-method set, quality control via correlation misfit assessment, and interactive correction. Using the Bazhenov formation in Western Siberia as an example, the study identifies potentially productive intervals and estimates porosity based on the search for multidimensional statistical relationships derived from integrated well-log data and core geochemical analyses. The presented OI workflow implemented in AutoCorr can be used to accelerate interpretation and substantiate reserve-estimation parameters for complex source-rock formations in poorly studied petroleum provinces.

References

1. GOST R 71476-2024 (ISO/MEK 22989:2022). Artificial intelligence. Artificial intelligence concepts and terminology.

2. Gutman I.S., Korrelyatsiya razrezov skvazhin slozhnopostroennykh neftegazonosnykh ob»ektov i geologicheskaya interpretatsiya ee rezul’tatov (Correlation of well sections of complex oil and gas objects and geological interpretation of its results), Moscow: ESOEN Publ., 2022, 336 p.

3. Spasennykh M., Maglevannaia P., Kozlova E. et al., Geochemical trends reflecting hydrocarbon generation, migration and accumulation in unconventional reservoirs based on pyrolysis data (on the example of the Bazhenov formation), Geosciences, 2021, No. 11, DOI: https://doi.org/10.3390/geosciences11080307

4. Kozlova E.V., Fadeeva N.P., Kalmykov G.A. et al., Geochemical technique of organic matter research in deposits enriched in kerogen (the Bazhenov formation, West Siberia) (In Russ.), Vestnik MGU. Seriya 4. Geologiya = Moscow University Geology Bulletin, 2015, no. 5, pp. 44–54.

5. Gutman I.S., Baturin A.Yu., Obgolts A.A. et al., Signs of hard-to-recover unconventional oil-producing rocks established in the process of its integrated study at the exploration and exploitation stages (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2023, No. 4, pp. 20-25, DOI: https://doi.org/10.24887/0028-2448-2023-4-20-25

6. Kozlova E.V., Bulatov T.D., Leushina E.A. et al., Geokhimicheskaya model’ netraditsionnogo kollektora v paleogenovykh otlozheniyakh Predkavkaz’ya (Geochemical model of an unconventional reservoir in the Paleogene deposits of the Ciscaucasia), Proceedings of 24th International Scientific and Practical Conference on the Exploration and Development of Oil and Gas Fields “Geomodel’ 2022”, Gelendzhik, 5–8 September 2022.

Petroleum potential within the Mesozoic sedimentary complex often depends on the deep structural model of the region, including large tectonic blocks, deep troughs, and surrounding uplifts, which determine the nature of the formation of younger structures. The article describes the hydrocarbon systems formation in the Barents-Kara region during Mesozoic stage. Based on a synthesis of deep drilling results, high-resolution seismic data, and core analysis, the authors performed seismic stratigraphic and seismic facies analyses, enabling them to reconstruct sedimentation environments and trace the cyclical structure of Triassic, Jurassic, and Cretaceous deposits. It is quite difficult to predict the organic matter type in the potential petroleum source rocks without sedimentary environments forecasting within the large structural zones. Paleogeographic zones were used to trace the properties of hydrocarbon system elements in areas without drilling. Particular attention is paid to petroleum source rocks of various genetic types. A full range of geochemical studies was conducted for most of the drilled wells in the Mesozoic sedimentary complexes, characterizing both the organic matter and hydrocarbons. Potential reservoirs associated with sand bodies of deltaic, alluvial, and coastal-marine origin, as well as regional seals could be the clayey strata of Toarcian, Callovian, and Upper Jurassic age. An attempt was made to reconstruct major sources and the main directions of sand material progradation.

References

1. Suslova A.A., Stoupakova A.V., Paleozoic hydrocarbon system formation in the Barents-Kara region (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2026, No. 3, pp. 18-24, DOI: https://doi.org/10.24887/0028-2448-2026-3-18-24

2. Suslova A.A., Mordasova A.V., Gilayev R.M. et al., Phanerozoic history of the Barents-Kara region as the framework for petroleum potential assessment (In Russ.), Georesursy, 2025, V. 27, No. 2, pp. 74–92, DOI: https://doi.org/10.18599/grs.2025.2.7

3. Stupakova A.V., Korobova N.I., Mordasova A.V. et al., Depositional environments as a framework for genetic classification of the basic criteria of petroleum potential (In Russ.), Georesursy, 2023, V. 25, No. 2, pp. 75–88, DOI: https://doi.org/10.18599/grs.2023.2.6

4. Dibner V.D., Morfostruktura shel’fa Barentseva morya (Morphostructure of the Barents Sea shelf), Leningrad: Nedra Publ., 1978, 211 p.

5. Gilmullina A., Klausen T.G., Dore A.G. et al., Arctic sediment routing during the Triassic – sinking the Arctic Atlantis, Journal of the Geological Society, 2023, V. 180,

No. 1, DOI: https://doi.org/10.1144/jgs2022-018

6. Kolesnikova T.O., Mordasova A.V., Suslova A.A. et al., Evolution and formation conditions of petroleum potential of the Barents-North Kara Sea shelf based on basin modelling (In Russ.), Georesursy, 2025, V. 27, No. 2, pp. 93–117, DOI: https://doi.org/10.18599/grs.2025.2.8

7. Stupakova A.V., Kiryukhina T.A., Suslova A.A. et al., Oil and gas prospects in the Mesozoic section of the Barents Sea basin (In Russ.), Georesursy, 2015, No. 2(61), pp. 13–26.

8. Stupakova A.V., Bol′shakova M.A., Suslova A.A. et al., Generation potential, distribution area and maturity of the Barents-Kara Sea source rocks (In Russ.), Georesursy, 2021, V. 23, No. 2, pp. 6–25, DOI: https://doi.org/10.18599/grs.2021.2.1

9. Norina D.A., Stroenie i neftegazomaterinskiy potentsial permsko-triasovykh terrigennykh otlozheniy Barentsevomorskogo shel’fa (Structure and oil and gas source potential of the Permian-Triassic terrigenous deposits of the Barents Sea shelf): thesis of candidate of geological and mineralogical science, Moscow, 2014.

10. Danyushevskaya A.I., Oil and gas producing strata of Phanerozoic deposits of the Arctic islands (In Russ.), Geokhimiya, 1995, No. 10, pp. 1495–1505.

11. Suslova A.A., Seismostratigraphic analysis and petroleum potential prospects of Jurassic deposits, Barents Sea shelf (In Russ.), Neftegazovaya geologiya. Teoriya i praktika, 2014, V. 9, No. 2, pp. 1–19.

12. Basov V.A., Pchelina T.M., Vasilenko L.V. et al., Obosnovanie vozrasta granits osadochnykh sekventsiy mezozoya na shel’fe Barentseva morya (Substantiation of the age of the boundaries of Mesozoic sedimentary sequences on the Barents Sea shelf), Collected papers “Stratigrafiya i paleontologiya Rossiyskoy Arktiki” (Stratigraphy and paleontology of the Russian Arctic), St. Petersburg: Publ. of VNIIOkeanogelogiya, 1997, pp. 35–48.

13. Suslova A.A., Neftegazonosnyy potentsial yurskikh otlozheniy Barentsevomorskogo basseyna (Oil and gas potential of the Jurassic deposits of the Barents Sea basin), Moscow: Nedra Publ., 2021, 197 p.

14. Zakharov V.A., Permian-Triassic boundary biotic crisis in the boreal biogeographic region (In Russ.), Proceedings of Geological Institute, 2006, V. 580, pp. 72–76.

15. Shurygin B.N., Nikitenko B.L., Meledina S.V. et al., Comprehensive zonal subdivisions of Siberian Jurassic and their significance for Circum-Arctic correlations

(In Russ.), Geologiya i geofizika = Russian Geology and Geophysics, 2011, V. 52(8), pp. 1051–1074.

16. Krasnova E.A., Izotopnaya geokhimiya ugleroda i kisloroda dlya resheniya zadach poiskovo-razvedochnykh rabot na neft’ i gaz (Carbon and oxygen isotope geochemistry for oil and gas exploration): thesis of doctor of geological and mineralogical science, Moscow, 2026.

17. Kiryukhina T.A., Stupakova A.V., Bol’shakova M.A. et al., Mesozoic oil and gas source deposits of the Barents Sea oil and gas potential basin (In Russ.), Geologiya nefti i gaza, 2012, No. 3, pp. 24–35.

18. Mordasova A.V., Stupakova A.V., Suslova A.A. et al., Oil and gas potential of the Arctic seas. Upper Jurassic and Lower Cretaceous clinoform complexes of the Barents-Kara shelf (In Russ.), Neftegaz.RU, 2019, No. 5, pp. 26–33.

Drilling wells in the Volga-Ural oil and gas province often involves drilling through intervals prone to caving and catastrophic mud losses. Despite successful mitigation of these challenging zones, this impacts wellbore quality and complicates casing running. Samaraneftegaz JSC and other Rosneft Group companies are constantly searching for new technologies to improve the efficiency of their operations. These include the use of a rotating liner during downhole operations, followed by cementing. This article provides an overview of devices for disconnecting the transport string from the liner: threaded and threadless (cam, lock and pin). Their operating principles and cementing procedures are described. As an example, a geological stratigraphic section and profile of a directional well at the Gazelnoye field are considered. Challenges encountered during liner drilling are described, including the failure of the drilling tool to move without rotating flushing, which resulted in the excessive removal of mudstone. The article briefly discusses liner assembly and preparation. It also provides technical details of the operations performed during liner rotation and the liner activation procedure. Graphical plots of hook weight, torque, and inlet pressure versus wellbore depth during the operation are presented. A description of how to disconnect the installation tool from the hanger and cement the liner is provided. A conclusion is drawn regarding the potential of using a rotating liner hanger packer within the 168×114 and 146×102 mm dimensions.

References

1. Balagurova N., Volgo-Ural’skaya neftegazonosnaya provintsiya: kharakteristika, mestorozhdeniya i strategicheskoe znachenie (Volga-Ural oil and gas province: characteristics, deposits and strategic importance), URL: https://fb.ru/article/466974/volgo-uralskaya-neftegazonosnaya-provintsiya-harakteristika-mestorojden...

2. Shipovskiy K.A., Tsirkova V.S., Koval’ M.E. et al., Improving the efficiency of prediction of lost circulation zones in the Neogene and Permian deposits. The case of Samara region oil fields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, No. 5, pp. 52–55, DOI: https://doi.org/10.24887/0028-2448-2020-5-52-55

3. Shipovskiy K.A., Tsirkova V.S., Koval’ M.E., Prediction and prevention of circulation loss in the Serpukhovian stage during wells drilling in Samara region fields

(In Russ.), Stroitel’stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2019, No. 9, pp. 35–39, DOI: https://doi.org/10.30713/0130-3872-2019-9-35-39

4. Shipovskiy K.A., Tsirkova V.S., Koval’ M.E. et al., Improving the efficiency of forecasting and preventing zones of complete and catastrophic lost circulation in reef structures of the Kama-Kinel downfold system (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, No. 12, pp. 97–101, DOI: https://doi.org/10.24887/0028-2448-2021-12-97-101

5. Shipovskiy K.A., Tsirkova V.S., Kozhin V.N. et al., Features of predicting complications in the zones of tectonic faults when drilling wells in the fields of the Samara region (In Russ.), Neftepromyslovoe delo, 2022, No. 10(646), pp. 20–25, DOI: https://doi.org/10.33285/0207-2351-2022-10(646)-20-25

6. Shipovskiy K.A., Tsirkova V.S., Koval’ M.E. et al., Trend of territorial distribution of the lost circulation areas and methods for lost circulation control at the Samara region fields (In Russ.), Neft’. Gaz. Novatsii, 2020, No. 6(235), pp. 62–69.

7. Rvalov M.A., Petrov M.V., Kapitonov V.A., Gilaev G.G., Design of directional and horizontal drilling wells in the Samara region (In Russ.), Burenie i neft’, 2022, No. 11,

pp. 3–8.

8. Shipovskiy, K.A., Kapitonov V.A., Koval’ M.E., Classification of absorption zones based on complications distribution patterns by tectonic elements in the Samara region (In Russ.), Stroitel’stvo neftyanykh i gazovykh skvazhin na sushe i na more, 2022, No. 11(359), pp. 18–22, DOI: https://doi.org/10.33285/0130-3872-2022-11(359)-18-22

9. Kapitonov V.A., Fedosenko O.V., Yurchenko V.V., Considering the factors that affect the stability of argillites (In Russ.), Neft’. Gaz. Novatsii, 2017, No. 10, pp. 22–25.

10. Miklyaev R.A., Ob′edkov O.P., Aver’yanov V.S. et al., Experience in applying liners sets with possibility of their rotation while rih (In Russ.), Neft’. Gaz. Novatsii, 2025, No. 1(290), pp. 21–24.

11. Basarygin Yu.M., Bulatov A.I., Proselkov Yu.M., Zakanchivanie skvazhin (Well completion), Moscow: Nedra-Biznestsentr Publ., 2000, 670 p.

12. Bulatov A.I., Savenok O.V., Zakanchivanie neftyanykh i gazovykh skvazhin: teoriya i praktika (Completion of oil and gas wells: theory and practice), Krasnodar: Prosveshchenie-Yug Publ., 2010, 542 p.

13. Podveska khvostovika tsementiruemaya zashchishchennaya vrashchaemaya PKhTsZV (Cemented, protected, rotating shank hanger (PKhTsZV)), URL: http://www.zers.ru/catalog/podveski-hvostovikov/podveska-hvostovika-czementiruemaya-zashhishhennaya-...

14. Tsementiruemye podveski khvostovikov (s vrashcheniem pri tsementazhe) (Cemented liner hangers (with rotation during cementing)), URL: https://aris-ot.ru/production/equipment-for-completion-wells/cementiruemye-podveski-hvostovikov-s-vr...

15. Paker-podveska khvostovika gidromekhanicheskaya, tsementiruemaya (s vrashcheniem) NPKF-PKh-GMTs-V-10000 PSI (69 MPa) (Hydromechanical, cemented (with rotation) liner packer-hanger NPKF-PKh-GMC-V-10000 PSI (69 MPa)), URL: https://www.npk-filtr.ru/npkf-ph-gmc-v-10000#rec145029960

16. Sychev V.A., Primenenie spetsial’nykh tamponazhnykh rastvorov pri tsementirovanii khvostovikov s vrashcheniem (Use of special cementing solutions for cementing liners with rotation): Master’s student’s final qualifying work, Tomsk: National Research Tomsk Polytechnic University, 2023, URL: http://earchive.tpu.ru/handle/11683/76209

This article is a summary of articles devoted to the search for optimal solutions for the development of reservoirs with low permeability using the example of the Erginsky license area, which is a testing ground for pilot industrial works to improve the efficiency of hard-to-recover reserves (HRR) production. The drilling of the horizontal well (HW) stock across the direction of propagation of the maximum regional stress for the development of transverse fractures proved to be more effective than the basic system of developing HW with longitudinal fractures of multi-stage hydraulic fracturing (HF) for low- permeability reservoirs. Based on geomechanical modeling and refinement of the fracture geometry in the HF simulator, a strategy for conducting pilot projects using various HF designs (six technologies at the first stage) was determined. According to the pilot test results, high-tech wells with an increased share of low-viscosity fluids showed an increase in productivity and cumulative production compared to standard large-volume HF with high-viscosity cross-linked guar-borate gel. The potential of using only low-viscosity fluids with an alternative fracturing job schedule with reduced proppant mass and increased fluid volume is noted. The article describes the results of changing the reservoir development strategy to increase the profitability of involving HRR in development. The influence of the HW orientation for the development of transverse fractures, various HF designs and the number of stages on the increase in cumulative production and well productivity is studied; studies of the interference of transverse fractures and microseismic monitoring of multi-stage HF are presented.

References

1. Rodionova I.I., Shabalin M.A., Kapishev D.Yu. et al., Choosing strategy of development of hard-to-recovery oil reserves at early stage of exploration (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, No. 12, pp. 132–135, DOI: https://doi.org/10.24887/0028-2448-2019-12-132-135

2. Bez TrIZ ne oboytis’ (We cannot do without hard-to-recover reserves), 2023, URL: https://www.cdu.ru/tek_russia/issue/2023/12/1212/

3. Weijers L., Wright C., Mayerhofer M. et al., Trends in the North American frac industry: Invention through the shale revolution, SPE-194345-MS, 2019,

DOI: https://doi.org/10.2118/194345-MS

4. Pearson C.M. et al., Twelve years and twelve thousand multi-stage horizontal wells in the Bakken – How is industry continuing to increase the cumulative production per well, Proceedings of SPE International Hydraulic Fracturing Technology Conference and Exhibition, Muscat, Oman, October 2018,

DOI: https://doi.org/10.2118/191455-18IHFT-MS

5. Tompkins D., Sieker R., Koseluk D., Cartaya H., Managed pressure flowback in unconventional reservoirs: a Permian basin case study, Proceedings of the 4th Unconventional Resources Technology Conference, 2016, DOI: https://doi.org/10.15530/urtec-2016-2461207

6. Zakrevskiy K.E., Nassonova N.V., Geologicheskoe modelirovanie klinoform neokoma Zapadnoy Sibiri (Geologic modeling of the West Siberian Neocomian clinoforms), Tver’: GERS Publ., 2012, 80 p.

7. Kapishev D.Yu., Rakhimov M.R., Mironenko A.A., The choice of the optimal system for the development of ultra-low-permeable reservoirs on the example of the Erginsky license area on the Priobskoye field (In Russ.), Ekspozitsiya Neft’ Gaz, 2022, no. 7, pp. 62–65, DOI: https://doi.org/10.24412/2076-6785-2022-7-62-65

8. Latypov I.D., Borisov G.A., Khaydar A.M. et al., Reorientation refracturing on RN-Yuganskneftegaz LLC oilfields (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2011, No. 6, pp. 34–38.

9. Sadykov A.M., Kapishev D.Yu., Erastov S.A. et al., Innovative hydraulic fracturing designs and recommendations for putting wells into production in conditions of ultra-low-permeability reservoirs on the example of the Erginsky license block of the Priobskoye field (In Russ.), Ekspozitsiya Neft’ Gaz, 2022, no. 7(92), pp. 80–85,

DOI: https://doi.org/10.24412/2076-6785-2022-7-80-85

10. Certificate of state registration of the computer program No. 2019660105 “Programmnyy kompleks dlya 1D geomekhanicheskogo modelirovaniya ustoychivosti stvola skvazhiny (PK “RN-SIGMA 2018”)” (Software package for 1D geomechanical modeling of wellbore stability (PC “RN-SIGMA 2018”)), authors: Davletova A.R., Knutova S.R., Fedorov A.I. et al.

11. Certificate of state registration of the computer program No. 2017611238 “RN-GRID” (RN-GRID), authors: Borshchuk O.S., Pestrikov A.V., Solov’ev D.E.

12. Kapishev D.Yu., Rodionova I.I., Sadykov A.M. et al., Selection of the operating mode of horizontal wells with large-volume multistage hydraulic fracturing on deposits with hard-to-recover oil reserves (In Russ.), Ekspozitsiya Neft’ Gaz, 2023, No. 7, pp. 84–89, DOI: https://doi.org/10.24412/2076-6785-2023-7-84-89

13. Erastov S.A., Sadykov A.M., Gallyamov I.F. et al., The study of propagation of multiple hydraulic fractures in horizontal wells for the case of infill drilling (In Russ.), Ekspozitsiya Neft’ Gaz, 2024, No. 5, pp. 44–49., DOI: https://doi.org/10.24412/2076-6785-2024-5-44-49

The article discusses the large-scale water shut-off workovers technology adaptation specifically for infill drilling wells, addressing the issue of bottom water coning in massive carbonate oil reservoirs. The core principle of the technology involves forming a gel barrier to restrict the influx of underlying water, thereby reducing premature water breakthrough in producers. The safe distance for packer placement during injection must be at least 8 meters along the wellbore taking into account the requirements for the technology of work. In 2023-2025, an optimized preventive large-scale water shut-off workovers program was implemented, successfully creating in-reservoir hydro-screen where the minimum distance between injection perforations and production intervals was only 4,5 meters. From 2020 to 2025, 50 operations were carried out at RUSVIETPETRO JV LLC fields, yielding over 465 tons of incremental oil. The article presents criteria for selecting candidate wells, methodology details, and a case study from the West-Khosedayuskoe field. The effectiveness of large-scale water shut-off workovers with traditional low-volume water shut-off workovers is compared. It is noted that large-scale water shut-off workovers not only enhances production and reduces water cut on individual wells but also increases recoverable reserves at the field scale, making it a promising comprehensive solution for developing massive carbonate reservoirs with active underlying aquifers.

References

1. Kubrak M.G., Application of remedial cementing in Samotlor oilfield (In Russ.), Neftegazovoe delo, 2011, no. 2, pp. 82–94,

URL: http://www.ogbus.ru/authors/Kubrak/Kubrak_1.pdf

2. Kubrak M.G., Sapel’chenko R.V., Stepanov A.N. et al., Enhancing the efficiency of large-volume water shut-off jobs in producing wells using thermotropic gelling argent (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2025, No. 5, pp. 99–102, DOI: https://doi.org/10.24887/0028-2448-2025-5-99-102

3 Makarshin S.V., Rogova T.S., Egorov Yu.A. et al., Assessment of opportunities for the use of gels based on aluminum salts for regulating filtration flows in carbonate reservoirs (In Russ.), Proceedings of VNIIneft, 2016, V. 155, pp. 22–36.

4. Nguyen Tri Dung, Pham Khac Dat, Ponomarenko D.M. et al., Evaluation of field trials of an in-situ gel-forming chemical system for water shut-off in production wells at the West-Khosedayu field and it’s application potential in Vietnam, DauKhi, 2025, No. 1, pp. 12–21, DOI: https://doi.org/10.47800/PVSI.2025.01-02

5. Stepanov A.N., Zoshchenko O.N., Ponomarenko D.M., Kubrak M.G., Results of pilot project of water coning prevention treatments using thermogelling compositions (In Russ.), PRONEFT’’. Professional’no o nefti = PRONEFT. Professionally about oil. 2025, V. 10, No. 1, pp. 83–89,

DOI: https://doi.org/10.51890/2587-7399-2025-10-1-83-89

6. Stepanov A.N., Fursov G.A., Ponomarenko D.M., High volume repair and insulation treatments as effective water coning prevention method (In Russ.), PRONEFT’. Professional’no o nefti = PRONEFT. Professionally about oil, 2023, no. 8(2), pp. 105–111, DOI: https://doi.org/10.51890/2587-7399-2023-8-2-105-111

7. Fursov G.A., Ponomarenko D.M., Opyt provedeniya remontno-izolyatsionnykh rabot na mestorozhdeniyakh Tsentral’no-Khoreyverskogo podnyatiya s primeneniem razlichnykh izoliruyushchikh geleobrazuyushchikh sostavov (Experience in carrying out repair and insulation works at the fields of the Central Khoreyver uplift using various insulating gelling compounds), Collected papers “Povyshenie effektivnosti razrabotki neftyanykh mestorozhdeniy” (Improving the efficiency of oil field development), Moscow: Publ. of National Agency for Support and Development, 2017, pp. 75–87.

8. Yudin E.V., Bagmanov R.D., Khairullin M.M. et al., Development of approach to modelling complex structure carbonate reservoirs using example of the central Khoreyver Uplift fields, SPE-187811-MS, 2017, DOI: https://doi.org/10.2118/187811-MS

Water hammer (hammer effect) is an oscillation of wellhead and bottomhole pressure that occurs after pump shutdown or a sudden change in fluid flow velocity in the wellbore during hydraulic fracturing operations. Water hammer analysis during the hydraulic fracturing is typically used to assess wellbore-fracture communication, to localize the location of the fracture, and to attempt to evaluate the fracture geometry and mechanical properties. The objective of the work is to model water hammer oscillations as acoustic waves in the wellbore to solve practical problems of actual pressure data analysis. The goal is to develop a methodology for estimating frictional pressure losses in tubing and perforations. This paper demonstrates how high-frequency actual pressure data of the first negative phase of water hammer can be used to determine the propagation velocity of water hammer waves, the distance from the wellhead to the fracture, and frictional pressure losses in the tubing and perforations. The proposed method is implemented in the RN-GRID hydraulic fracturing simulator. Given the pumps were stopped quickly enough to form clear water hammer wave fronts, the estimate of the hydraulic friction coefficient obtained using the method proposed, agrees well with the actual data. The paper also includes the discussing of the limitations of the method and the challenges of water hammer data analysis in general, and examines the potential future applications for online bottomhole pressure estimation during the injection.

References

1. Zhukovskiy N.E., O gidravlicheskom udare v vodoprovodnykh trubakh (Completion of oil and gas wells: theory and practice), Vol. 3: Gidravlika. Prikladnaya mekhanika (Hydraulics. Applied Mechanics), Moscow–Leningrad: Gostekhizdat Publ., 1949, pp. 7–152.

2. Patzek T.W., Silin D.B., Lossy transmission line model of hydrofractured well dynamics, SPE-46195-MS, 1998, DOI: https://doi.org/10.2118/46195-MS

3. Ghidaoui M.S., Zhao M., McInnis D.A., Axworthy D.H., A review of water hammer theory and practice, Applied Mechanics Reviews, 2005, No. 58(1), pp. 49–76,

DOI: https://doi.org/10.1115/1.1828037

4. Wang, X. Hovem K., Quan Y., Water hammer effects on water injection well performance and longevity, SPE-112282-MS, 2008,

DOI: https://doi.org/10.2118/112282-MS

5. Lyapidevskiy V.Yu., Neverov V.V., Krivtsov A.M., Mathematical model of water hammer in vertical wellbore (In Russ.), Sibirskie elektronnye matematicheskie izvestiya, 2018, V. 15, pp. 1687–1696, DOI: https://doi.org/10.33048/semi.2018.15.140

6. Carey M.A., Mondal S., Sharma M.M., Analysis of water hammer signatures for fracture diagnostics, SPE-174866-MS, 2015, DOI: https://doi.org/10.2118/174866-MS

7. Il’yasov A.M., A new approach to the hydraulic fracture geometric dimensions determination (In Russ.), Trudy Instituta mekhaniki im. R.R. Mavlyutova UNTs RAN, 2017, V. 12, No. 1, pp. 126–134, DOI: https://doi.org/10.21662/uim2017.1.018

8. Baykov V.A., Bulgakova G.T., Il’yasov A.M., Kashapov D.V., To the evaluation of the geometric parameters of hydraulic fracturing crack (In Russ.), Mekhanika zhidkosti i gaza, 2018, No. 5, pp. 64–75, DOI: https://doi.org/10.31857/S056852810001790-0

9. Shagapov V.Sh., Bashmakov R.A., Chiglintseva A.S., Damped natural vibrations of fluid in a well interfaced with a reservoir (In Russ.), Prikladnaya mekhanika i tekhnicheskaya fizika, 2020, V. 61, No. 4, pp. 136–146, DOI: https://doi.org/10.15372/PMTF20200401

10. Dunham E.M., Zhang J., Moos D., Constraints on pipe friction and perforation cluster efficiency from water hammer analysis, SPE-212337-MS, 2023,

DOI: https://doi.org/10.2118/212337-MS

11. Dunham E.M., Building well and fluid-specific pipe friction curves, monitoring perforation cluster efficiency during stimulation, and measuring near-wellbore tortuosity using acoustic friction analysis, Proceedings of Unconventional Resources Technology Conference (URTeC), 2024, DOI: https://doi.org/10.15530/urtec-2024-4044718

12. McFall R., De La Garza J., Khan M., Using real-time acoustic friction analysis for completions design evaluation, Proceedings of the 2025 Unconventional Resources Technology Conference, 2025, DOI: https://doi.org/10.15530/urtec-2025-4264923

13. Akhtyamov A.A., Makeev G.A., Baydyukov K.N. et al., Corporate fracturing simulator RN-GRID: from software development to in-field implementation (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, No. 5, pp. 94–97, DOI: https://doi.org/10.24887/0028-2448-2018-5-94-97

14. Makeev G.A., Fattakhova A.F., Friction pressure loss analysis on typical hydraulic fracturing data (In Russ.), PRONEFT’’. Professional’no o nefti = PRONEFT. Professionally about oil, 2024, No. 9(1), pp. 95–105, DOI: https://doi.org/10.51890/2587-7399-2024-9-1-95-105

15. Makeev G.A., Determining hydraulic friction of a fluid using water hammer pressure actual data (In Russ.), SIIT, 2026, V. 8, No. 2(26), pp. 57–72,

DOI: https://doi.org/10.54708/SIIT-2026-no2-p57

16. Rouleau W.T., Pressure surges in long pipelines carrying viscous liquids, Journal of Basic Engineering, 1960, V. 82, No. 4, pp. 915–920,

DOI: https://doi.org/10.1115/1.3662800

According to current rules established in 2019 for field development projects there is a need to shut down wells upon reaching at least one of the following indicators: the water cut reaches 98 %, the oil flow rate drops below 0,5 tons per day or gas factor reaches 2500 m3 per ton. These well shutdown criteria are the same for all fields. At the same time, upon closer examination of the issue, it should be noted that these well shutdown criteria must be specified for different geological conditions. Using the example of 25 fields of a major oil company in the Khanty-Mansi Autonomous Okrug-Yugra, a differentiation of the criteria for shutting down wells in highly watered well stock was made depending on the tax system and the level of company costs in comparison with the amount of mineral extraction tax. It is shown that highly productive production wells in the oil fields of Western Siberia can be profitably operated even after reaching a water cut of 98 %, maintaining high liquid flow rates. The approach to substantiating the marginal cost-effective technological indicators of well operation presented in this paper can be used for field development projects and to justifying the recovery factor for oil fields.

References

1. Yakunin I.A., Voronina A.I., On the number of samples to establish the current water cut of wells in the B1 formation of the Zhirnovskaya area (In Russ.), Neftepromyslovoye delo, 1972, No. 5, pp. 35–37.

2. Leybin E.L., Chervyakov N.N., Vysochinskiy A.S. et al., On the number of samples for determining the monthly water cut of production wells (In Russ.), Neftepromyslovoye delo, 1981, No. 10, pp. 15–17.

3. Yemel′yanov D.V., Khazigaleyev R.R., Sharipov I.F. et al., The impact of implementation of the flask-based water cut sampling method on the Samotlor field development (In Russ.), Neftyanoye khozyaystvo = Oil Industry, 2025, No. 11, pp. 26–30, DOI: https://doi.org/10.24887/0028-2448-2025-11-26-30

4. Asmandiyarov R.N., Kladov A.E., Lubnin A.A. et al., Automatic approach to field data analysis (In Russ.), Neftyanoye khozyaystvo = Oil Industry, 2011, No. 6, pp. 58–61

5. Serdyukov O.L., Optimizatsiya ucheta i otbora prob skvazhinnoy produktsii (Optimization of well production sampling and accounting), Proceedings of XV anniversary conference of young specialists working in organizations engaged in activities related to the use of subsoil sites in the Khanty-Mansi Autonomous Okrug – Yugra, Khanty-Mansiysk, 19–22 May 2015, Khanty-Mansiysk, 2015, pp. 197–200.

6. Belov V.G., Ivanov V.A., Solov′yev V.YA., Measurement of oil wells production watering (In Russ.), Neftyanoye khozyaystvo = Oil Industry, 2003, No. 4, pp. 111–113.

7. Chudin V.I., Anufriyev V.A., Shuvayeva L.A. et al., New solution to establish the content of water, oil and gas in well product (In Russ.), Neftyanoye khozyaystvo = Oil Industry, 2004, No. 1, pp. 86–88.

8. Shaydullin F.D., Nazmiyev I.M., Denislamov I.Z. et al., Improving the accuracy of water cut measurements in oil wells (In Russ.), Neftepromyslovoye delo, 2005, No. 5, pp. 29–31.

9. Bobylev O.A., Determination of wells watering at their periodic operation (In Russ.), Neftyanoye khozyaystvo = Oil Industry, 2005, No. 6, pp. 122–123.

10. Voronkov V.S., Galimov A.A., Samoylov D.YU. et al., Improvements in efficiency of water cut measurements for production wells (In Russ.), Neftyanoye

khozyaystvo = Oil Industry, 2020, No. 7, pp. 43–45, DOI: https://doi.org/10.24887/0028-2448-2020-7-43-45

11. Vlasov D.YU., Alekseyeva A.A., Syundyukov A.V. et al., Algorithm for automation of expert averaging of water cut in oil production (In Russ.), Neftyanoye

khozyaystvo = Oil Industry, 2024, No. 12, pp. 58–62, DOI: https://doi.org/10.24887/0028-2448-2024-12-58-63

12. Order of the Ministry of Natural Resources and Ecology of the Russian Federation No. 356 of June 14, 2016 (as amended by order No. 638 of September 20, 2019) “Ob utverzhdenii pravil razrabotki mestorozhdeniy uglevodorodnogo syr’ya” (On the approval of the rules for the development of hydrocarbon deposits),

URL: https://www.consultant.ru/document/cons_doc_LAW_334817/

This paper addresses the development of a neural network-based model for predictive assessment of potentially productive areas and effective exploration of remaining oil reserves. The object of study is a subsurface area comprising three oil fields with a reserve depletion rate of approximately 80 %. Additionally, the subject area has experienced a significant decline in annual oil production over an extended period. Input data include reservoir characteristics from more than 2000 wells producing exclusively from a single formation. The uniqueness of the approach lies in incorporating temporal dynamics (cumulative well operation time) together with static parameters (net pay thickness, net sand ratio, porosity, oil and gas saturation), enabling the modeling of oil production rates with graphical data representation. The optimal network configuration was identified as a multilayer perceptron with six hidden layer nodes. Predictive analysis was performed for 14 target areas identified for potential geological and technical operations. Forecast results for production rates and performance characteristics of future typical wells were obtained. The trained neural network models were preserved and can be applied to any field area using only a few input variables. Thus, the objective of predictive assessment and identification of productive zones was achieved, area ranking was performed, the most high-risk zones were identified, and the effectiveness of integrating neural network modeling into geological and technical operations planning was confirmed.

References

1. Boyd D., Crawford K., Six provocations for Big Data, SSRN Electronic Journal, 2011, V. 123, No. 1, DOI: http://doi.org/10.2139/ssrn.1926431

2. Siegel E., Liftoff: The basics of predictive model deployment, Predictive Analytics World, 2021, URL: https://www.predictiveanalyticsworld.com/blog/liftoff-the-basics-of-predictive-model-deployment/

3. Markin V.A., Markina L.V., Bayramov V.R. et al., Data Mining methods as a decision support system under conditions of data limitation (In Russ.), Neftyanoye khozyaystvo = Oil Industry, 2024, No. 5, pp. 138–142, DOI: https://doi.org/10.24887/0028-2448-2024-5-138-142

4. Markin V.A., Markina L.V., Bayramov V.R. et al., Intellectual analysis as a method of knowledge discovery in field development (In Russ.), Neftyanoye khozyaystvo = Oil Industry, 2025, No. 5, pp. 132–136, DOI: https://doi.org/10.24887/0028-2448-2025-5-132-136

The permeability recovery coefficient of the porous medium of a productive reservoir at the interface with a fracture formed after hydraulic fracturing is one of the most important parameters determining its effectiveness. Therefore, in the process of laboratory research, a special role is assigned to the methodology of conducting the test experiment for the experimental evaluation of this parameter's magnitude under specific reservoir conditions when using a particular fracturing fluid. An analysis of various experimental methods shows that standard laboratory studies using a flow cell do not enable the direct determination of this parameter's value. The use of reservoir models with mixture of sand and сlay with given permeability and the imitation of a hydraulic fracture enables comparative experiments to investigate the effectiveness of different fracturing fluids with good reproducibility of results due to the specific structure of the porous medium. However, the use of models made of several core samples or a single core sample from the specific section of the productive reservoir where hydraulic fracturing is intended, as the porous medium, significantly refines the obtained result. It should be noted that each experimental methodology has its inherent limitations and advantages. The article proposes a methodology for conducting experiments using a single core sample, justifying the parameters for fracturing fluid injection, as well as the conditions for modeling the well completion process after the impact of fracturing fluid on the porous medium during laboratory research.

References

1. ISO 13503-5:2006. Petroleum and natural gas industries — Completion fluids and materials Part 5: Procedures for measuring the long-term conductivity of proppants.

2. MR-ISM-03-OLFI-058-2013. Metod izmereniy pronitsaemosti i provodimosti rasklinivayushchikh napolniteley (proppantov) na real’nom kerne v modeliruemykh plastovykh usloviyakh (Method for measuring the permeability and conductivity of proppant fillers (proppants) on a real core under simulated reservoir conditions).

3. Chertenkov M.V., Aleroev A.A., Ivanishin I.B. et al., Physical modeling of production stimulation in low permeability carbonate reservoirs (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, No. 10, pp. 90–92. – EDN: UXQXMP

4. Gubanov V.B., Magadova L.A., Malkin D.N., Express method for laboratory determination of reservoir permeability recovery coefficient as a result of exposure to hydraulic fracturing fluid (In Russ.), Nafta-Gaz, 2017, No. 4, pp. 236–241.

5. Laboratorno-izmeritel’nyy kompleks dlya issledovaniya neftevytesneniya: rukovodstvo po ekspluatatsii. Model’ CFS 700 (Laboratory and measuring complex for oil displacement research: operating manual. Model CFS 700), Vinci Technologies, Nanter, 2015.

6. ISO 13503-4:2006. Petroleum and natural gas industries — Completion fluids and materials Part 4: Procedure for measuring stimulation and gravel-pack fluid leakoff under static conditions.

Steam-based thermal technologies are widely used in the development of heavy and extra-heavy oil reservoirs. Particular attention is paid to improving the efficiency of thermal energy utilization injected into the reservoir, including through the implementation of in-situ upgrading processes. The use of transition metal-based catalysts contributes to a reduction in oil viscosity and an increase in its mobility. This leads to an increase in oil recovery. A promising approach is the application of reagents capable of disrupting the supramolecular structures of asphaltenes. This enhances the accessibility of weak carbon–heteroatom bonds and promotes their subsequent degradation under hydrothermal conditions. This study investigates the effect of a thermally stable surfactant-peptizer on the physicochemical properties of heavy oil from the Aksenovskoye field under pilot field conditions. Oil samples were collected over a four-week period, four months after reagent injection. Rheological properties, group composition (SARA), and various characteristics of asphaltenes were analyzed. To elucidate the nature of intermolecular interactions in asphaltene structures, quantum chemical calculations were performed, including Hirshfeld surface analysis, which enabled to identify potential interaction sites and explain the tendency of asphaltenes to aggregate. The obtained results confirm that the action of the surfactant-peptizer (TU 20.59.59-003-02066730-2025) leads to the dispersion of asphaltene aggregates, increased oil mobility under reservoir conditions, and enhanced oil recovery.

References

1. Ganeeva Yu.M., Yusupova T.N., Romanov G.V., Asphaltene nano-aggregates: structure, phase transitions and effect on petroleum systems (In Russ.), Uspekhi

khimii = Russian Chemical Reviews, 2011, V. 80, no. 10, pp. 1034–10502. Fedorov R.A., Akopyan A.V., Anisimov A.V., Karakhanov E.A., Peroxide oxidative desulfurization of crude petroleum in the presence of fatty acids, International Journal of Biology and Chemistry, 2018, V. 11, No. 2, pp. 173–178, DOI: https://doi.org/10.26577/ijbch-2018-2-337

3. Kholmurodov T., Vakhin A.V., Mirzaev O. et al., Non-ionic surfactant influence on peptization of asphaltene agglomerates in heavy oil under hydrothermal conditions in the Na-Fe3O4 catalyst presence, Fuel, 2025, V. 393, pp. 134966, DOI: https://doi.org/10.1016/j.fuel.2025.134966

4. Kholmurodov T.A., Mirzaev O.O., Vakhin A.V. et al., The phenomenon of asphaltenes’ peptization to improve steam-thermal methods efficiency for heavy oil fields development (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, No. 7, pp. 109–112, DOI: https://doi.org/10.24887/0028-2448-2024-7-109-112

5. Kholmurodov T., Tajik A., Galyametdinov Y. et al., Mechanism of surfactant peptization in the process hydrocatalytic degradation of asphaltenes in heavy oils, Fuel, 2025, V. 381, DOI: https://doi.org/10.1016/j.fuel.2024.133490

6. Malaniy S.Ya., Slavkina O.V., Ryazanov A.A. et al., Field test of catalytic aquathermolysis technology at Strelovskoye oil field in the Samara region (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 12, pp. 118–121, DOI: http://doi.org/10.24887/0028-2448-2022-12-118-121

7. Protsenko A.N., Malaniy S.Ya., Bakumenko E.A. et al., Downhole catalytic hydrogenation of carbon dioxide during thermal enhanced heavy oil recovery (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2022, no. 12, pp. 114-117, DOI: https://doi.org/10.24887/0028-2448-2022-12-114-117

8. Patent RU2794400C1. Composition for intensifying the production of hard-to-recover hydrocarbon reserves and a method for its production, Inventors: Kholmurodov T.A., Vakhin A.V., Sitnov S.A., Mirzaev O.O.

9. Betiha M.A., Elmetwally A.E., Al-Sabagh A.M., Mahmoud T., Catalytic aquathermolysis for altering the rheology of asphaltic crude oil using ionic liquid modified magnetic MWCNT, Energy and Fuels, 2020, V. 34(9), pp. 11353–11364, DOI: https://doi.org/10.1021/acs.energyfuels.0c02062

10. Vakhin A.V., Aliev F.A., Mukhamatdinov I.I. et al., Extra-heavy oil aquathermolysis using nickel-based catalyst: Some aspects of in-situ transformation of catalyst precursor, Catalysts, 2021, V. 11(2), No. 189, pp. 1–22, DOI: https://doi.org/10.3390/catal11020189

11. Kholmurodov T.A., Aliev F.A., Mirzaev O.O. et al., Hydrothermal in-reservoir upgrading of heavy oil in the presence of non-ionic surfactants, Processes, 2022, V. 10, No. 11, DOI: https://doi.org/10.3390/pr10112176

12. Kholmurodov T.A., Mirzaev O.O., Affane B. et al., Thermochemical upgrading of heavy crude oil in reservoir conditions, Processes, 2023, V. 11, No. 7,

DOI: https://doi.org/10.3390/pr11072156

13. Yanping Wang a , Qiuxia Wang b, Da Yang et al., Synthesis and properties evaluation of novel Gemini surfactant with temperature tolerance and salt resistance for heavy oil, Journal of Molecular Liquids, 2023, V. 382, DOI: https://doi.org/10.1016/j.molliq.2023.121851

14. Okhotnikova E.S., Barskaya E.E., Ganeeva Y.M. et al., Catalytic conversion of oil in model and natural reservoir rocks, Processes, 2023, V. 11, No. 8,

DOI: https://doi.org/10.3390/pr11082380

15. Aliev F., Mirzayev O., Kholmurodov T. et al., Experimental insights into catalytic conversion of carbon dioxide during in-reservoir hydrothermal upgrading of heavy oil, Fuel, 2025, V. 396, DOI: https://doi.org/10.1016/j.fuel.2025.135326

Efficient management of oil field development using reservoir pressure maintenance systems requires accurate assessment of pressure interaction between injection and production wells. This paper presents a method for determination of well connectivity coefficients using Graph Attention Network (GATs). This method implies formalization of well system as directed graph, where nodes represent wells with their performances, while edges represent potential well connections. GAT model is trained to predict production well performance based on historical data (flow rates, pressures, water cut, well spacing), rather than directly calculate the connectivity coefficient. The key advantage of this approach is that target connectivity coefficients are extracted from inherent weights of model attention mechanism, which reflect the contribution of each injection well to pressure change in particular production well. Multi-head architecture enebles simultaneous analysis of fluid-flow effects and spatial factors. The experiments were conducted in two stages. The first stage entailed model training and validation based on simulated data obtained from reservoir simulation model. The second stage included successful test run of this method using actual data from Bobrikovian sediments of Romashkinskoye field. Thus, the developed method offers a tool to obtain physically interpretable estimates of well interactions directly from historical production data. This opens up opportunities for development of intelligent monitoring systems and adaptive optimization of waterflood patterns to ultimately improve the performance of oil field development.

References

1. Zhao-Qin Huang, Zhao-Xu Wang, Hui-Fang Hu et al., Dynamic interwell connectivity analysis of multi-layer waterflooding reservoirs based on an improved graph neural network, Petroleum Science, 2024, V. 21, No. 2, pp. 1062–1080, DOI: https://doi.org/10.1016/j.petsci.2023.11.008

2. Cunliang Chen, Wei Zhang, Baolin Yue, Bin Liu, A new method for quantitative description of dominant channels in high water-cut stage, Improved Oil and Gas Recovery, 2022, V. 7, 7 p., DOI: https://doi.org/10.14800/IOGR.1212

3. Bo Li, Hui Zhao, Botao Liu et al., Graph neural networks and hybrid optimization for water-flooding regulation, Physics of Fluids, 2025, V. 37(8),

DOI: https://doi.org/10.1063/5.0268372

4. Heffer K.J., Fox R.J., McGill C.A., Koutsabeloulis N.C., Novel techniques show links between reservoir flow directionality, Earth stress, fault structure and geomechanical changes in mature waterfloods, SPE-30711-PA, 1997, DOI: https://doi.org/10.2118/30711-PA

5. Gaysin A.A., Nizaev R.Kh., A comprehensive approach to well interference modeling using physically-based graph neural networks (In Russ.), Neftyanaya provintsiya, 2025, No. 4, pp. 251–265, DOI: https://doi.org/10.25689/NP.2025.4.251-265

6. Senin P., Dynamic time warping algorithm review. Information and Computer Science Department University of Hawaii at Manoa Honolulu, USA, 2008, V. 855 (1–23).

7. RD 153-39.0-109-01. Metodicheskie ukazaniya po kompleksirovaniyu i etapnosti vypolneniya geofizicheskikh, gidrodinamicheskikh i geokhimicheskikh issledovaniy neftyanykh i neftegazovykh mestorozhdeniy (Guidelines for the integration and staging of geophysical, hydrodynamic and geochemical studies of oil and oil and gas fields): approved by order of the Ministry of Energy of Russia No. 30 on February 5, 2002, URL: http://techexpert.tatneft.ru/docs/

8. Gaysin A.A., Isroilov N.K. Gilyazov A.Kh., Reservoir pressure calculation in producing wells using machine learning methods (In Russ.), Neftyanaya provintsiya, 2024, No. 3, pp. 123–136, DOI: https://doi.org/10.25689/NP.2024.3.123-136

The article considers practical experience of the information technology department at Tyumenneftegazproekt LLC in developing and maintaining the technical documentation management system (TDMS). The work is relevant due to the need of design institutes to adapt to the growing requirements of oil and gas companies regarding timelines, formats, structure of design documentation amidst industry digitalization. The objective was to transform the TDMS from a passive file repository into an active tool for managing the design documentation lifecycle. Three key directions were implemented. The first technical adaptation and system programming tailored to specific design processes using VBScript to automate completeness control and compliance of drawings with customer standards. The second development of an integration layer based on C# and F#, ensuring two-way data exchange between TDMS, AutoCAD and MS Office. The third analytics and optimization of design documentation approval routes. Special attention is paid to formalizing customer requirements and organizing external interaction through the Easla.com cloud platform. The practical significance is confirmed by the achieved results: reduction of drawing inspection time by 67 %, increase in design documentation processing speed by 35 %, reduction of human error by 80 %, decrease in average document approval time by 30 %. These results demonstrate that targeted development of a legacy system with a systematic approach to integration, process reengineering, and user communication is an economically viable alternative to implementing new expensive platforms. This enables a design institute to build competitive advantages in the oil and gas industry project services market.

References

1. Didichin D.G., Pavlov V.A., Vykhodtsev A.V. et al., New tools of Rosneft Oil Company for improving design efficiency: oil-and-gas institutes productionactivity monitoring (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, No. 5, pp. 127–132, DOI: https://doi.org/10.24887/0028-2448-2024-5-127-132

2. Golitsyna T.D., Integration of product data management systems and computer-aided design systems: From partial solution to global strategy (In Russ.), Izvestiya vysshikh uchebnykh zavedeniy. Priborostroenie, 2009, V. 52, No. 3, pp. 42–46.

3. Hammer M., Champy J., Reengineering the corporation: A manifesto for business revolution, Harper Business, 1993, 223 p.

4. GOST R 21.101-2020. System of design documentation for construction. Main requirements for design and working documentation.

The article discusses the issue of applying new methods for diagnosing and monitoring the technical condition of storage tanks for oil and petroleum products. It is shown that the current tank diagnostics system in the Russian Federation, despite its development and the high efficiency of the diagnostic methods used, is not always capable of promptly identifying new and rapidly developing defects due to the periodic nature of implementation. At the same time, the systems used today for monitoring technical condition of tanks are economically costly. A comparative analysis of the most effective and widespread tank diagnostics methods is conducted. It is demonstrated that the requirements for these control methods limit the possibility of their application for monitoring. The authors proposed to consider unmanned aerial vehicles with cameras for infrared (hyperspectral) imaging as a tool for monitoring the technical condition of tanks. It is established that modern unmanned aerial vehicles possess sufficient technical characteristics for their use in tank diagnostics. A fundamental algorithm for the use of unmanned aerial vehicles with cameras for infrared (hyperspectral) imaging for monitoring the technical condition of storage tanks is proposed. The main problems and tasks that need to be addressed in further research to implement the method proposed by the authors are highlighted.

References

1. Kondrasheva O.G., Nazarova M.N., Cause and effect analysis of vertical steel tank failures (In Russ.), Neftegazovoe delo, 2004, No. 2, p. 19.

2. Vasil’ev G.G., Sal’nikov A.P., Analysis of causes of accident with vertical steel tanks (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, No. 2, pp. 106–108.

3. GOST 31385-2023. Vertical cylindrical steel tanks for oil and oil-products. General specifications, URL: https://docs.cntd.ru/document/1302050679

4. GOST R 58623-2019. Trunk pipeline transport of oil and oil products. Vertical cylindrical steel tanks. Rules of technical operation, URL: https://docs.cntd.ru/document/1200169168

5. Gorban’ N.N., Vasil’ev G.G., Sal’nikov A.P., Predictive monitoring system of technical condition of marine oil terminals (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2025, No. 8, pp. 89–93, DOI: https://doi.org/10.24887/0028-2448-2025-8-89-93

6. GOST 27751-2014. Reliability for constructions and foundations. General principles, URL: https://docs.cntd.ru/document/1200115736

7. Safety Guide «Recommendations for the technical diagnosis of welded vertical cylindrical tanks for oil and oil products», URL: https://docs.cntd.ru/document/1303139887

8. GOST 7512-82. Nondestructive testing. Welded joints. Radiography method, URL: https://docs.cntd.ru/document/1200001358

9. GOST R 55724-2013. Non-destructive testing. Welded joints. Ultrasonic methods, URL: https://docs.cntd.ru/document/1200107569

10. GOST R 56512-2015. Non-destructive testing. Method of magneting particle testing. Standard technological processes,

URL: https://docs.cntd.ru/document/1200122220

11. GOST 18442-80. Nondestructive testing. Capillary methods. General requirements, URL: https://docs.cntd.ru/document/1200004648

12. Safety Guide “Guidelines on the procedure for conducting acoustic emission testing”, URL: https://docs.cntd.ru/document/1314426387

13. RD 153-112-017-97. Instruktsiya po diagnostike i otsenke ostatochnogo resursa vertikal’nykh stal’nykh rezervuarov (Instructions for the diagnosis and evaluation of the residual life of vertical steel tanks), URL: https://gostassistent.ru/doc/2ac5debc-9b41-441b-a45e-f19b3c9bc3b2

14. Giperspektral’noe mashinnoe zrenie: tekhnologiya i primery primeneniya (Hyperspectral machine vision: Technology and applications),

URL: https://diext.ru/2025/11/23/giperspektralnoe-mashinnoe-zrenie-tehnologiya-i-primery-primeneniya/

On time steel pipelines corrosion defects detection is one of the key factors ensuring the reliable and safe operation of main subsea pipelines. This article presents the results of internal cleaning (pigging) and in-line inspection (ILI) performed to assess the remaining life of subsea pipelines operated by Vietsovpetro JV. It should be noted that the selected subsea pipelines have been in service for more than 25 years, exceeding their design life, pigging and ILI were carried out for them for the first time. A brief description of the methodological approach used for the analysis of ILI data is provided. The calculation procedure is based on the practical recommendations of DNV-RP-F101 and employs a three-level approach: selection and analysis of residual wall thickness based on ILI data; assessment of residual strength for each defect; and assessment of residual strength for clusters (groups of interacting defects). It was found that despite the long service life of the pipelines, more than 85 % of all defects is within the category of up to 40 % metal loss and are not critical. The most hazardous detected defects are located on the above-water parts of the vertical pipeline sections (risers) and are generally formed as a result of atmospheric corrosion. The study identified the differences in the chemical composition of solid deposits in oil gathering, gas-lift, and water injection pipelines. Spatial distribution features of corrosion defects in subsea pipelines were established depending on the transported fluid and its conditions.

References

1. Mazur I.I., Ivantsov O.M., Bezopasnost' truboprovodnykh sistem (Safety of pipeline systems), Moscow: Elima Publ., 2004, 1104 p.

2. Recommended Practice DNV-RP-F101 Corroded Pipelines, Det-Norske-Veritas, Norway, 2015.

3. Bai Y., Bai Q., Subsea pipeline integrity and risk management, Gulf Professional Publishing, 2014, 429 p.

4. Borodavkin P.P., Morskie neftegazovye sooruzheniya (Marine engineering structures), Part 1. Konstruirovanie (Designing), Moscow: Nedra-Biznestsentr Publ., 2006, 555 p.

5. Savel’ev V.V., Bovt A.V., Ivanov A.N. et al., Comprehensive approach to preventing failures of Vietsovpetro subsea pipelines (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2024, No. 10, pp. 32–38, DOI: https://doi.org/10.24887/0028-2448-2024-10-32-38

Transneft PJSC conducts experimental studies of the residual life of pipes and welds with various types of defects identified during pipeline diagnostics. The goal of the studies is to improve the methodology for determining the permissible service life of pipelines with defects. One of the directions in ensuring the safe operation of main pipelines is the improvement of computational models for determining the strength and durability of pipes with defects. The most reliable method for verifying improved computational models is comparing calculation results with experimental test data of full-scale samples of pipes with defects. This raises the problem of determining the minimum number of pipe samples for conducting experimental studies sufficient to validate the calculations taking into account the scatter of test results. To address the issue, the article analyzes the scatter of residual life test results for the pipes with defects of the same type, a relative residual life parameter is proposed, and a normal distribution law is demonstrated. The occurrence of the fraction of relative residual life parameter distribution within the required interval with a given confidence probability according to GOST R 50779.21 - 2004 is analyzed. A methodology for determining the minimum required number of test pipes in a given sample is developed. The minimum number of test samples is calculated for different confidence probabilities. During the calculation, the minimum number of test pipes ensuring the specified requirements is determined. Based on these results, it was concluded that in order to take into account the natural dispersion of test results for full-scale pipe samples with defects of the same type, the minimum required number of samples in the sample is 15 with a confidence level of 0,99.

References

1. Cochran W.G., Sampling Techniques, Wiley, 1977, 428 p.

2. Johnson N.L., Leone F.C., Statistics and experimental design in engineering and the physical sciences, Wiley, 1977, 1090 p.

3. Gmurman V.E., Teoriya veroyatnostey i matematicheskaya statistika (Theory of probability and mathematical statistics), Moscow: Vysshaya shkola Publ., 2002, 479 p.

4. Bakaeva O.A., Determining the minimum sample size (In Russ.), Vestnik mordovskogo universiteta, 2010, No. 1, pp. 111–114.

5. GOST R ISO 5479-2002. Statistical methods. Tests for departure of the probability distribution from the normal distribution.

6. GOST R 50779.21 – 2004. Statistical methods. Determination rules and methods for calculation of statistical characteristics based on sample data. Part 1. Normal distribution.