Given high extent of depletion of the production assets and maturing of the main oil fields in the Republic of Tatarstan, the Tatneft’s objective to sustain the current level of the annual production can be attained through increase of effectiveness of geologic exploration playing a significant role in reserves replacement. The paper presents an overview of geologic exploration works carried out on the territory of Tatneft PJSC operations in the Republic of Tatarstan in the period from 2016 to 2020. Geophysical survey has always been the main instrument in the geologists’ repertoire of tools applied at all stages of exploration. The authors analyze the effectiveness of the geophysical methods. To reduce risks and to optimize geological prospecting, the Company uses an integrated package of technologies. The higher the quality of geologic prospecting, the higher the chance of new discoveries, and the latter is the main criterion of the exploration success.

Maintaining of the existing oil production level in Tatarstan is not conceivable without reserves replacement. For the last five years, extension additions made 73% of total addition to reserves of the Tatneft. The Company’s priorities as regards reserves replacement are: search for new fields, as well as for poorly explored unconventional oil reserves (heavy oil, domanik sediments, carbonate fractured reservoirs, tight reservoirs, sediments in the crystalline basement, sediments of the Riphean-Vendian age); search for small-sized and low-amplitude accumulations, lithologically or stratigraphically screened accumulations; development of novel exploration technologies and improvement of the existing ones; providing a rather dense network of microseismic monitoring and continuous updating of databases, including revision of all acquired data, re-processing and re-interpretation of field data.

Notwithstanding high extent of depletion of the main productive assets (80%) and increase of the share of hard-to-recover reserves (over 87%), the effectiveness of geologic prospecting has increased from 83 to 86%. The Company continues to develop new technologies aimed at reserves’ addition from complex unconventional reservoirs, and to conclude new foreign contracts, which will add to economic growth of Tatarstan and Russia.

References

1. Khisamov R.S., Bazarevskaya V.G., Ziyatdinov A.G. et al., Evaluation of geological and economic efficiency of prospecting and exploratory drilling at license blocks of Tatneft PJSC (In Russ,), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 7, pp. 6–7, DOI: 10.24887/0028-2448-2018-7-6-7.

2. Khisamov R.S., Bazarevskaya V.G., Bachkov A.P. et al., Confirmability of geophysical data by drilling and well production testing in the territory of Tatneft’s activities  (In Russ,), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 7, pp. 12–14, DOI: 10.24887/0028-2448-2018-7-12-14.

To satisfy a need for reserves replacement, large Russian vertically-integrated companies pay closer attention to unconventional hydrocarbon sources with hard-to-recover reserves, in particular, the Domanic sediments and the heavy oil accumulations in the Permian formations. Tatneft PJSC considers these reserves of strategic importance that are able to provide for oil production increase and diversification of the resource base on the territory of the Republic of Tatarstan. For the last five years, the Domanic sediments add annually 8 million tons to incremental reserves. The Company’s experience of development of heavy oil accumulations in the Sheshminskian sand sequences has shown that exploration and development of unconventional resources call for out-of-the-box approaches and, as a consequence, huge investments. In accordance with the Science and Technology Development Strategy of the Russian Federation and the relevant Resolution of the Government of the Russian Federation, Tatneft PJSC is involved in development of the comprehensive full innovation cycle R&D project for study and development of unconventional reserves in the DOMANIC and BITUM testing sites in Tatarstan. The comprehensive full innovation cycle R&D project is aimed at development of novel heavy oil exploration and reservoir engineering technologies. Considering the ever-decreasing chances of new large conventional hydrocarbon discoveries, the significance of the project is self-evident.

The paper discusses the prospects and the progress of the R&D project, and the importance of the governmental support for unconventional hydrocarbon reserves development projects.

References

1. Khisamov R.S., Bazarevskaya V.G., Anoshin D.V., Geologicheskaya uspeshnost' vypolneniya opytno-promyshlennykh rabot v skvazhinakh, vskryvshikh domanikovye otlozheniya na territorii deyatel'nosti PAO “Tatneft'” (Geological success of pilot works in wells penetrating domanik sediments on the territory of Tatneft operations), Proceedings of TatNIPIneft / Tatneft PJSC, 2020, V. 88. pp. 15–22.

2. Minnikhanov R.N., Maganov N.U., Khisamov R.S., On creation of research and testing facilities to promote study of nonconventional oil reserves in Tatarstan (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 8, pp. 60–62.

Well construction in carbonate rock intervals is accompanied by presence of cavernous fractured zones with low reservoir pressure and is complicated by drill mud and cement slurry losses. Loss of circulation is a typical problem for the most of the Tatarstan fields, so, best practices have been established during the decades. Two-stage cementing technique and light-weight cement slurries are used to provide top of cement up to the wellhead. Light-weight cementing slurry is prepared by adding agents of much lower density compared to cement or those agents that increase water-cement ratio. The major drawbacks of light-weight slurries are low set cement strength and technical difficulties of cement mixing.

The paper summarizes light-weight slurries development for production casing cementing at Tatneft assets. Light-weight cement slurries can be prepared based on standard cement using several techniques. These include increasing the volume of liquid phase in a slurry by adding, for example, water retaining agents; mixing of standard cement with lower-density fluids, such as oil and oil products; adding of solid agents with lower density than that of cement; cement slurry aerating. Tatneft was the first to use clays and gel powders as lightweight agents. The Company still uses light-weight cement slurries based on oil-well Portland cement and bentonite powder which are mixed in the dry state by multiple repacking at cement Contractor’s storage depot. The key contributor to density reduction is high water cement ratio, which adversely affects the set cement strength. Previously, different agents were used as light porous fillers for cement slurries, including perlite, expanded clay, foamed vermiculite, pumice, lignin. However, because of low triaxial compressive strength of porous fillers, they had limited application area. For this reason, other types of materials have come into common use, such as aluminosilicate, glass, ceramic and foam-glass microbeads.

References

1. Kateev I.S., Issledovanie i sovershenstvovanie sposobov povysheniya kachestva krepleniya skvazhin na pozdney stadii razrabotki neftyanykh mestorozhdeniy (Research and improvement of methods for improving the quality of well casing at the late stage of oil field development): thesis of candidate of technical science, Ufa, 1978.

2. Iskhakov A.R., Zaripov I.M., Ismagilov A.A., Razrabotka tekhnologii tsementirovaniya obsadnykh kolonn s ispol'zovaniem alyumosilikatnykh polykh mikrosfer (Development of casing cementing technology using hollow aluminosilicate microspheres), Proceedings of youth scientific and practical conference dedicated to the production of three billion tons of oil by Tatneft OAO, Al'met'evsk, 2007, Part 1, pp. 54–55.

3. Ryabokon' S.A., Novokhatskiy D.F., Sovremennoe sostoyanie v oblasti tamponazhnykh tsementov i rastvorov (Current state in the oil-well cements and mortars), Collected papers “Sovremennaya tekhnologiya i tekhnicheskie sredstva dlya krepleniya i remontno-izolyatsionnykh rabot neftyanykh i gazovykh skvazhin” (Modern technology and technical means for casing and repair and insulation works of oil and gas wells), Proceedings of NPO Burenie OAO, 2000, V. 5, pp. 75–88.

4. Gazizov M.G., Zaripov A.M., Zaripov I.M. et al., Optimizatsiya retseptury tamponazhnogo rastvora s ispol'zovaniem poristykh steklyannykh polnotelykh granul pri tsementirovanii ekspluatatsionnykh kolonn v OAO “Tatneft'”  (Optimization of the grouting slurry formulation using porous glass full-bodied granules when cementing production strings at Tatneft), Collected papers “Reagenty i materialy, tekhnologicheskie sostavy i burovye zhidkosti dlya stroitel'stva, ekspluatatsii i kapital'nogo remonta neftyanykh, gazovykh i gazokondensatnykh skvazhin” (Reagents and materials, technological compositions and drilling fluids for construction, operation and overhaul of oil, gas and gas condensate wells), Proceedings of XVI International scientific-practical conference, Suzdal, 5–8 July 2012, Vladimir: Publ. of VlSU, 2012, pp. 130–135.

5. Kateev R.I., Amerkhanova S.I., Zaripov I.M. et al., Tamponazhnyy rastvor so steklyannymi granulami (Grouting mortar with glass granules), Proceedings of TatNIPIneft' / Tatneft', 2013, V. 81, pp. 275–281.

6. Vakula A.Ya., Belonogov S.V., Kateev R.I. et al., Pilot using of alleviated cement slurry in "Tatneft" JSC (In Russ.), Burenie i neft', 2013, no. 4, pp. 26–28.

7. Kateev R.I., Zaripov A.M., Shayakhmetov A.Sh., Rezul'taty opytno-promyslovykh ispytaniy oblegchennykh tamponazhnykh rastvorov v PAO «Tatneft'» pri tsementirovanii v odnu stupen' (Results of field trials of lightweight grouting slurries at Tatneft PJSC during one-stage cementing), Collected papers “Reagenty i materialy dlya stroitel'stva, ekspluatatsii i remonta neftyanykh, gazovykh skvazhin: proizvodstvo, svoystva i opyt primeneniya. Ekologicheskie aspekty neftegazovogo kompleksa” (Reagents and materials for the construction, operation and repair of oil and gas wells: production, properties and application experience. Environmental aspects of the oil and gas complex), Proceedings of XXII International scientific-practical conference, 5-8 June 2018, Vladimir: Arkaim Publ., 2018, pp. 82–85.

8. Patent RU 2 588 026 C1, Lightweight plugging composition, Inventors: Kateev R.I., Amerkhanova S.I., Shayakhmetov A.Sh., Gabbasov T.M., Latypova D.V., Gazizov M.G.

9. Zaripov I.M., Iskhakov A.R., Kateev R.I., Zaripov A.M., Tatneft’s experience in well completion using fiberglass-reinforced plastic casing strings (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 7, pp. 18–19, DOI: 10.24887/0028-2448-2018-7-18-19.

10. Patent RU 2 720 025 C1, Casing string cementing method in well, Inventors: Zaripov I.M., Iskhakov A.R., Shayakhmetov A.Sh.

11. Kateev R.I., Zaripov A.M., Bikbulatov R.R., Kozlov A.V., Lightweight cement slurry with the addition of a foam glass ceramic (In Russ.), Burenie i neft', 2018, no. 3, pp. 28–31.

12. Zaripov I.M., Iskhakov A.R., Kateev R.I. et al., Issledovanie kombinirovannogo napolnitelya dlya uluchsheniya tamponiruyushchikh svoystv tsementnogo rastvora (Study of the combined filler to improve the plugging properties of the cement slurry), Proceedings of TatNIPIneft' / Tatneft', 2019, V. 87, pp. 240–245.

13. Shigabutdinov A.S., Gimatdinov V.N., Shakirov I.R. et al., Pilot industrial work on the introduction of foam cementing technology  (In Russ.), Burenie i neft', 2020, no. 4, pp. 28–32.

Pilot project implemented in the Bavlinsky deposit of Pashian horizon identified some features of oil-drainage line movement, oil-water contact raising, showed no severe breakthrough and water fingering subject to proper reservoir management, as well as demonstrated mechanism of non-uniform movement and constriction of oil-drainage boundaries. The experiment showed that although considerable amount of oil is displaced from the water-oil zone into the oil zone during peripheral waterflooding, oil losses due to undeveloped water-oil zone or due to wide well spacing are quite high. Therefore, the water-oil zone should be developed with the same well pattern as the oil zone. It should be noted that the maximum efficiency is achieved by well drilling in this zone from the very start of field production. According to various studies, oil losses in the Bavlinskoye oil field due to wide well spacing make 4.7-12.7%, which is much higher than it was projected (0.25-1.5%). The results of geologic model calculations showed that oil losses due to wide well spacing made 7.4-7.7%. To assess oil losses during wide well spacing experiment and its effect on oil recovery from D1 horizon, multiversion numerical simulation is required with changing well operation conditions, time and sequence of well shutting-in and putting on production, which will enable detecting oil flow paths towards producing wells with due regard for specific geological structure. A 60-years’ experience in D1 horizon development shows that adjustment of well interventions included in the previously approved technical project documentation provided oil recovery increase.

References

1. Muslimov R.Kh., The outstanding role of the Bavlinskoye oil field in the formation of high technologies for the development of productive strata (In Russ.), Georesursy, 2006, no. 3 (20), pp. 3–7.

2. Khisamov R.S., Ganiev G.G., Khannanov R.G. et al., Scientific and practical significance of the discovery and development of the Bavlinsky oil field (In Russ.), Georesursy, 2006, no. 3 (20), pp. 8–10.

3. Khammadeev F.M, Sultanov S.A., Poluyan I.G., Eksperimental'naya razrabotka Bavlinskogo mestorozhdeniya (Pilot production of Bavlinskoye field), Kazan': Tatknigoizdat Publ., 1975, 111 p.

4. Dorokhov O.I., Poluyan I.G., Sultanov S.A., Large-scale experiment in Bavlinskoye field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 1959, no. 3, pp. 41–46.

5. Dorokhov O.I., Metodika izucheniya nefteotdachi v promyslovykh usloviyakh na Bavlinskom neftyanom mestorozhdenii (Field study of oil recovery in Bavlinsky field), Scientific and technical collection of oil production / VNII, 1961, V. 13, pp. 56–60.

6. Dorokhov O.I., Sultanov S.A., Poluyan I.G., Promyshlennyy eksperiment na Bavlinskom mestorozhdenii po izucheniyu vliyaniya plotnosti setki na protsess ekspluatatsii i nefteotdachu (Industrial experiment at the Bavlinskoye field to study the effect of grid density on the process of operation and oil recovery), Collected papers “Opyt razrabotki neftyanykh i gazovykh mestorozhdeniy” (Experience in the development of oil and gas fields), Proceedings of All-Union meeting, Kiev, 1961, Moscow: Gostoptekhizdat Publ., 1963, pp. 35–41.

7. Muslimov R.Kh., Nikolaev V.A., Sultanov S.A., Poluyan I.G., Preliminary results of Bavlinsky pilot project (In Russ.), Neftyanoe khozyaystvo = Oil Industry, Neftyanoe khozyaystvo, 1981, no. 7, pp. 30–38.

The paper describes algorithms for predicting oil production rates based on Arps model whose parameters are estimated in terms of well production performance and the algorithm based on panel data models with a trend component described by Arps model. An algorithm for selection of input factors based on Bayesian neural networks has been proposed and implemented. An algorithm for construction of piecewise multiple regression models to estimate the Arps constant and to predict oil production rates based on application of Kohonen networks and structural change analysis approaches has been proposed and implemented. This method for prediction of oil production rate and production decline considers numerous factors that influence production performance. A module for prediction of oil production performance of project wells has been developed. The host application is written in Python 3.6 programming language. Computational algorithms of model building are implemented in R programming language. The authors describe the principle of operation of software module for forecasting oil production performance of project wells.

The described method has been field tested at production sites of Tatneft Company. Machine learning has been done using selected geological and production data from producing wells in Kynovian and Pashian reservoirs for a group of production areas of Romashkinskoye field. Machine learning enabled selection of project wells and estimation of production and economic performance. A comparative analysis of existing methods for prediction of input oil production rates and annual production decline rates of project wells for the selected group of areas has been performed. Resultant data suggest applicability of machine learning method for prediction of production performance of project wells in oil fields. This is particularly important for mature fields, which provide sufficient accumulated statistical data required to apply machine learning methods.

References

1.  Latifullin F.M., Sattarov Ram.Z., Sharifullina M.A., Application of lazurit workstation software package for geological and reservoir modeling and well intervention planning for Tatneft’s production assets (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 6, pp. 40–43, DOI: 10.24887/0028-2448-2017-6-40-43.

2. Nasybullin A.V., Sattarov Ram.Z., LatifullinF.M. et al., Creation of software tool for long-term investment planning with a view to the effective development of oil fields (In Russ.), Neftjanoe hozjajstvo = Oil Industry, 2019, no. 12, pp. 128–131, DOI: 10.24887/0028-2448-2019-12-128-131.

3. Khisamov R.S., Ganiev B.G., Galimov I.F. et al., Computer-aided generation of development scenarios for mature oil field (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 7, pp. 20–25, DOI: 10.24887/0028-2448-2020-7-22-25.

4. Lysenko V.D., Proektirovanie razrabotki neftyanykh mestorozhdeniy (Oil field development design), Moscow: Nedra Publ., 1987, 247 p.

5. Silaev K.O., Silaeva A.N., Methods for the analysis of production decline curves used in the fuel and energy sector (In Russ.), Ekonomika i sotsium, 2016, no. 9(28), pp. 543–546, URL: https://readera.org/ekonomika-socium/2016-9-28.

6. Gujarati D.N., Basic econometrics, McGraw-Hill, 1995, 1003 p.

7. Poirier D.J., The econometrics of structural change, Amsterdam: North-Holland, 1976, 206 p.

8. Kohonen T., Self-organizing maps, New York, 2001, 501 p.

9. Rousseeuw P.J., Tutorial to robust statistics, Journal of chemometrics, 1991, V. 5, no. 1, pp. 1–20.

10. Huber P.J., Robust statistics, New York: John Wiley & Sons, 1981.

11. Faddeenkov A.V., Khaylenko E.A., Estimation of regression model parameters by the trimmed maximum likelihood method (In Russ.), Nauchnyy vestnik Novosibirskogo gosudarstvennogo tekhnicheskogo universiteta, 2016, V. 65, no. 4, pp. 135–145.

12. Denisov V.I., Timofeev V.S., Sign method: advantages, problems, algorithms (In Russ.), Nauchnyy vestnik Novosibirskogo gosudarstvennogo tekhnicheskogo universiteta, 2001, no. 1 (10), pp. 21–35.

13. Timofeev V.S., Vostretsova E.A., Robust estimation of regression model parameters based on ideas of least-square method (In Russ.), Nauchnyy vestnik Novosibirskogo gosudarstvennogo tekhnicheskogo universiteta, 2007, no. 2 (27), pp. 57–67.

14. Timofeev V.S., The characteristic function in parameter estimation problem for regression model (In Russ.), Nauchnyy vestnik Novosibirskogo gosudarstvennogo tekhnicheskogo universiteta, 2010, no. 2 (39), pp. 43–52.

Currently underway is commercial production of extra-viscous oil in the fields of the Republic of Tatarstan using steam-assisted gravity drainage (SAGD) technique. A large amount of updated field data obtained during appraisal drilling as a preparatory stage for extra-viscous oil production operations, systematization of geophysical and geological data with rock typing, paleogeographic reconstructions and modeling enabled identification of the zones exhibiting oil saturation heterogeneity and complex geological structure. A significant factor interfering with the production of extra viscous oil is the presence of shaled-out interlayers associated with lack of reservoir continuity, when a sharp change of facies types from predominantly sandstone to interbedding clays, siltstones and sands is observed in shallow marine shelf conditions on bar slopes and barrier islands. Prior to operation of horizontal wells drilled in such zones a number of issues shall be tackled. Firstly, it is necessary to select optimal compositions depending on rock mineralogy, calculate the required injection volume and concentration of chemical agents, which will also depend on rock characteristics (the clay and carbonate component), such that the injection volume be large enough to provide the desired benefits, on the one hand, and not too large to favor the formation of direct flow channels between parallel horizonal (injection and production) wells which will further lead to steam breakthrough.  Negative effects on tubing string and perforation interval shall be minimized through selection of optimal composition and treatment strategy. To date, combined efforts of specialists from research and production departments of Tatneft Company resulted in development of the technology that mitigates detrimental effects of the above-mentioned factors during the development of extra-viscous oil reservoirs using SAGD technique.

References

1.  Takhautdinov Sh.F., Sabirov R.K., Ibragimov N.G. et al., Sozdanie i promyshlennoe vnedrenie kompleksa tekhnologiy razrabotki mestorozhdeniy sverkhvyazkikh neftey (The creation and implementation of technology complex for heavy oil deposits development), Kazan': Fen Publ., 2011, 142 p.

2. Beregovoy Ant.N., Knyazeva N.A., Vasil'ev E.P. et al., Povyshenie effektivnosti razrabotki zalezhey sverkhvyazkoy nefti s uplotnennymi i zaglinizirovannymi kollektorami (Improving the efficiency of the development of extra-viscous oil deposits with seal and mudded-off collectors), Proceedings of TatNIPIneft' / Tatneft PJSC, 2019, V. 87, pp. 137–144.

3. Amerkhanov M.I., Zaripov A.T., Beregovoy Ant.N. et al., Process engineering solutions to improve heavy oil development at Tatneft assets (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 1, pp. 60-65, DOI: 10.24887/0028-2448-2020-1-60-65.

4. Patent no. 2686768 RF, MPK E21B 43/27, E21B 43/24, E21B 7/04, E21B 49/00, C09K 8/72, Method for development of super-viscous oil and/or bitumen deposit in compacted and clogged reservoirs (versions), Inventors: Amerkhanov M.I., Beregovoy A.N., Vasil'ev E.P., Knyazeva N.A., Razumov A.R.

Considerable portion of Russian oil fields, including the Volga-Ural region, are at the late stage of development and are characterized by production decline. This decline is attributable to depletion of active oil reserves with the resultant increase in the share of residual oil trapped in unswept zones. Other contributing factors are increase in water cut of complex terrigenous reservoirs and substantial reservoir compartmentalization. Such reservoirs are typically developed using waterflooding method. This well-proven and relatively cost-effective method still has its limitations.  Different viscosities of crude oil and displacing agent, and their immiscibility as well as reservoir heterogeneity are the primary factors affecting water-oil displacement efficiency.

Target oil recovery factor can be achieved through improvement of water (displacing agent) displacing ability or reservoir sweep efficiency. Various flow diversion technologies have been implemented and applied in Tatneft PJSC. Of these, gel-forming compositions, dispersion systems and sedimentation agents have gained wide acceptance. However, application of such compositions can cause total blockage of high and medium permeability intervals that contain considerable oil reserves despite high water saturation. This puts such intervals out of operation for a long time to the extent that the entire reservoir becomes non-producing. At the same time restoring production from blocked intervals requires complex and costly operations. Consequently, permanent shut-down of individual reservoirs cay result in increase of the share of hard-to-recover oil reserves and decrease of ultimate oil recovery. In light of the above, application of low-impact flow diversion technologies becomes urgent. These technologies enable temporary blockage and suppression of water flow in flushed high- and medium permeability reservoir zones.  The common practice is to use hydrocarbon-based emulsion compositions exhibiting the above properties. Emulsion compositions improve sweep efficiency and facilitate conformance control to prevent rapid breakthrough of injected water towards production well due to high viscosity of the emulsion. Adjustable viscosity enables penetration of emulsion composition into flushed high-permeability zones, redistribution of injected water to lower permeability zones and complete oil recovery from unswept reservoir zones.

References

1. Zaripov A.T., Beregovoy Ant.N., Knyazeva N.A. et al, Development and application of emulsion-based technologies to enhance production from Tatneft PJSC assets (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 7, pp. 40–43, DOI: 10.24887/0028-2448-2019-7-40-43

2. Patent no. 2110675 RF, MPK E 21 V 43/22, Invert microemulsion for treating oil beds.

3. Beregovoy A.N., Amerkhanov M.I., Rakhimova Sh.G., Vasil'ev E.P., Application of invert emulsions enhances conformance in heterogeneous formations (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2010, no. 8, pp. 116–118.

4. Patent no. 2379326 RF, MPK C 09 K 8/584, Water repellent emulsion for oil reservoirs treatment, Inventors: Ibatullin R.R., Amerkhanov M.I., Rakhimova Sh.G., Beregovoy A.N., Andriyanova O.M., Khisamov R.S.

5. Patent no. 2613975 RF, MPK V 01 F 17/00, C 09 K 8/00, C 11 D 1/04, 3/43. Invert emulsions emulsifier, Inventors: Sakhabutdinov R.Z., Beregovoy A.N., Rakhimova Sh.G., Andriyanova O.M., Fadeev V.G., Amerkhanov M.I., Nafikov A.A.

6. Amerkhanov M.I., Nafikov A.A., Beregovoy Ant.N. et al., Predvaritel'nye rezul'taty primeneniya novogo emul'gatora invertnykh emul'siy s tsel'yu uvelicheniya stepeni nefteizvlecheniya mestorozhdeniy PAO “Tatneft'” (Preliminary results of the use of a new emulsifier of invert emulsions in order to increase the degree of oil recovery of Tatneft fields), Proceedings of TatNIPIneft' / PAO “Tatneft'”, 2017, V. 85, pp. 211-216.

7. Patent no. 2660967 RF, MPK E 21 V 43/22, C 09 K 8/92, E 21 V 43/16, Method of treating non-uniform permeability oil reservoir by injection of invert emulsion, Inventors: Zaripov A.T., Beregovoy A.N., Rakhimova Sh.G., Medvedeva N.A., Lakomkin V.N., Amerkhanov M.I., Nafikov A.A.

One of the priorities in oil and gas industry is determining quality of chemical agents used in well drilling, completion, operation, workover, production stimulation, and enhanced oil recovery processes. Use of chemicals in oil production processes is a global trend and an integral part of the present-day strategy of improving oil and gas field development efficiency. Advanced use of chemicals for oil production stimulation is now focused on synthesis and development of composite chemical systems. In addition to conventional inorganic acids, more complex components are used with increasing frequency, such as organic acids, chelate compounds, as well as a series of chemical agents to control acid-rock reaction kinetics and to selectively react with specific lithological components of reservoir rock and to change (control) structure and viscosity parameters. Considering these domestic and global trends, the importance of research in the field of testing and ranking composite acid systems based on specific geologic and physical field conditions is beyond dispute. Modern innovative approaches stipulate the necessity and importance of digitizing and ranking physical and chemical properties of chemical products in order to effectively and scientifically select chemical agents for targeted and efficient production stimulation operations.

The paper discusses the procedure of identifying the most viable acid system formulations for various productive formations based on rank differentiation of formulations according to their physical and chemical parameters.

References

1. Brian C., Metcalf S., Stimulation of oil production in the San Andres area thanks to the use of a weak acid (In Russ.), Neftegazovye tekhnologii, 2009, no. 12, pp. 21–24.

2. Fjelde I., Sulfate in rock samples from carbonate reservoirs, Proceedings of International Symposium of the Society of Core Analysts held in Abu Dhabi, 12 p.

3. Gomari K.A.R, Karoussi O., Hamouda A.A., Mechanistic study of interaction between water and carbonate rocks for enhancing oil recovery, SPE-99628-MS, 2006, DOI: https://doi.org/10.2118/99628-MS.

4. Høgnesen E.J., Strand S, Austad T., Waterflooding of preferential oil-wet carbonates: Oil recovery related to reservoir temperature and brine composition, Proceedings of 14th Europec Biennial Conference held in Madrid, Spain, 13-16 June 2006, DOI: https://doi.org/10.2118/94166-MS.

5. Lungwitz B., Fredd C., Brady M. et al., Diversion and cleanup studies of viscoelastic surfactant-based self-diverting acid, SPE-86504-PA, 2007, DOI: https://doi.org/10.2118/86504-PA

6. Manchanda R., Sharma M.M., Impact of completion design on fracture complexity in horizontal shale wells. Equilibrium Test-A method for closure pressure determination, SPE-159899-PA, 2014, DOI: https://doi.org/10.2118/159899-PA.

7. Nasr-El-Din H.A., Van Domelen M., Welton T., Sierra L., Optimization of surfactant-based fluids for acid diversion, SPE-107687-MS, 2007, DOI: https://doi.org/10.2118/107687-MS

8. Webb K.J., Black C.J.J., Tjetland G., A laboratory study investigating methods for improving oil recovery in carbonates, Proceedings of International Petroleum Technology Conference in Doha, Qatar, 21–23 November 2005, DOI: https://doi.org/10.2523/IPTC-10506-MS.

9. Xie Kh., Weiss W.W., Tong Z., Morrow N.R., Improved oil recovery from carbonate reservoirs by chemical stimulation, SPE-89424-MS, 2004, DOI: https://doi.org/10.2118/89424-MS

10. Ibragimov N.G., Musabirov M.Kh., Yartiev A.F., Tatneft’s experience in commercialization of import-substituting well stimulation technologies (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2015, no. 8, pp. 86–89.

11. Yartiev A.F., Tufetulov A.M., Musabirov M.H., Grigoryeva L.L., Enhancement of horizontal well oil recovery by means of chemical stimulation, Asian Social Science, 2015, V. 11, no. 11, pp. 346–356.

12. Khisamov R.S., Musabirov M.Kh., Yartiev A.F., Uvelichenie produktivnosti karbonatnykh kollektorov neftyanykh mestorozhdeniy (Increase in productivity of carbonate reservoirs of oil fields), Kazan': Ikhlas Publ., 2015, 192 p.

13. Zakirov I.S., Zakharova E.F., Musabirov M.Kh., Ganiev D.I., Approaches to assessing the effectiveness of chemicals on core material of Domanic deposits (In Russ.), Neftyanaya provintsiya, 2019, no. 3(19), pp. 141–155, DOI: https://doi.org/10.25689/NP.2019.3.141-155.

14. Ibragimov N.G., Musabirov M.Kh., Dmitrieva A.Yu. et al., On necessity of targeted approach to selection of chemical systems for bottomhole zone treatment of Tulskian-Bobrikovskian reservoirs (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2018, no. 7, pp. 20–23, DOI: 10.24887/0028-2448-2018-7-20-23.

15. Musabirov M.Kh., Dmitrieva A.Yu., Podbor kislotnykh kompozitsiy dlya obrabotki prizaboynoy zony plastov mestorozhdeniy NGDU “Bavlyneft'” (Selection of acid compositions for treatment of bottomhole formation zones of oil and gas production department "Bavlyneft"), Proceedings of TatNIPIneft' / PAO “Tatneft'”, 2017, V. 85, pp. 217–228.

16. Patent RU 2724832 C1, Complex procedure for selection of acid compositions for intensification of oil production in domanic deposits, Inventors: Zakirov I.S., Zakharova E.F., Dmitrieva A.Yu., Budkevich R.L., Ganiev D.I.

17. Dmitrieva A.Yu., Musabirov M.Kh., Abusalimov E.M. et al., Innovative foam-acid technology of bottom-hole area for intensification of oil production from carbonate reservoirs in PJSC "Tatneft" (In Russ.), Ekspozitsiya Neft' Gaz, 2016, no. 5, pp. 30–33.

18. Ibragimov N.G., Ismagilov F.Z., Musabirov M.Kh., Abusalimov E.M., Analysis of well stimulation pilot projects in Tatneft OAO (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2014, no. 7, pp. 40–43.

The article presents the results of reservoir simulation modeling of alternative surfactant-polymer composition applications to increase oil recovery in high-permeability porous-type reservoirs containing highly viscous oil. Justification for application of reservoir simulator is provided, peculiar aspects of the applied model compared to commercial software products are revealed, a brief description of the target and associated issues are presented. FlowER software package was used to predict the performance of chemical treatment and select the optimal composition and injection volume for the pilot surfactant-polymer flood project developed in Tatneft. Automatic history matching of the resultant model to actual field data was done in FlowER software package with selection of the main reservoir properties, relative permeability functions. Laboratory studies of the properties of two types of chemical compositions depending on component concentrations were conducted. A series of simulation runs were performed to determine the optimal injectivity of injection wells at different injection volumes with the assumption of bottomhole pressure limitation. Injection of surfactant-polymer system was simulated for various volumes and component concentrations. Dependencies of oil production increment on injection volume were obtained. The paper also presents production vs. injection volume variations, well injectivity changes during injection volume increase as well as after injection of the design volume with variations of formation pore volume. Comparison of two types of compositions at different component concentrations was performed, their efficiency with the increase of surfactant or polymer concentrations was evaluated.

References

1. Garipova L., Persova M., Soloveichik Y. et al., Optimization of high-viscosity oil field development using thermo-hydrodynamic modeling, Proceedings of 19th International Multidisciplinary Scientific GeoConference SGEM, 30 June – 6 July 2019, Sofia, 2019, V. 19, pp. 473–480, DOI: https://doi.org/10.5593/sgem2019/1.3/S03.060

2. Persova M.G., Soloveichik Y.G., Vagin D.V. et al., The design of high-viscosity oil reservoir model based on the inverse problem solution, Journal of Petroleum Science and Engineering, 2021, V. 199, DOI: https://doi.org/10.1016/j.petrol.2020.108245

3. Persova M.G., Soloveichik Y.G., Ovchinnikova A.S. et al., Numerical 3D simulation of enhanced oil recovery methods for high-viscosity oil field, Proceedings of 14th International Forum on Strategic Technology (IFOST 2019), 14th-17th October 2019, Tomsk, Russian Federation, IOP Conference Series: Materials Science and Engineering, 2021, V. 1019, URL: https://iopscience.iop.org/article/10.1088/1757-899X/1019/1/012050/meta/.

4. Khisametdinov M.R., Trofimov A.S., Rafikova K.R. et al., Determination of optimal polymer flooding parameters using reservoir simulation model (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 9, pp. 90–93, DOI: 10.24887/0028-2448-2019-9-90-93.

5. Persova M.G., Soloveychik Yu.G., Vagin D.V. et al., Podkhod k avtomaticheskoy adaptatsii gidrodinamicheskoy modeli mestorozhdeniya vysokovyazkoy nefti na osnove resheniya mnogomernoy obratnoy zadachi mnogofaznoy fil'tratsii (An approach to automatic adaptation of a hydrodynamic model of a high-viscosity oil field based on solving a multidimensional inverse problem of multiphase filtration), Proceedings of 21st EAGE conference on oil and gas geological exploration and development – Geomodel 2019, Gelendzhik, September 9–13, 2019.

Tracer investigations is a direct and one of the most reliable methods to determine presence/source of subsurface connectivity, which have found use in geological exploration for study of reservoir fluids’ behavior and diagnostics of horizontal wells without resorting to well logging, as well as in environmental studies for evaluation of leak integrity of waste pits and search for pollution sources. In oil industry, the efficacy of tracer investigations is determined by the tracer characteristics. Tritium used to be applied on a wide scale in previous years, has all necessary characteristics to provide for accuracy and reliability of results, however, it does not meet the requirements regarding nuclear safety, so its application is restricted. Tracer systems in current use, which are organic dyes (fluorescent, ionic, alcoholic), also have a number of drawbacks, namely, a limited product range, a complicated procedure for quantitative identification of tracers. Besides, bright colors of fluorescent tracers considerably restrict hydrogeological surveys and might affect applicability of fresh water resources. To improve efficiency of upstream operations, it is important to find optimal tracers for reservoir studies to have real-time data about reservoir fluids’ behavior, inflow of reservoir fluids to wells, including horizontal wells. The synthesized carbon quantum dots specimens allowed to expand the range of tracers. The laboratory tests determined the efficiency of carbon quantum dots in comparison with the known fluorescein tracers. The paper presents a number of key indicators determined in the course of experiments such as minimal measurement limit (luminescent emission intensity), Stokes shift (difference between waves of excitation and emission), and results of core analyses. The synthesized carbon quantum dots made possible to expand the applicability of tracers and to improve performance as compared with conventional tracers. Results of laboratory experiments demonstrate good potential of the synthesized carbon quantum dots as tracers for reservoir management and ecological monitoring.

References

1. Zaytsev V.I., Sokolovskiy E.V., Sultanov S.A. et al., Primenenie tritievogo indikatora dlya kontrolya za razrabotkoy neftyanykh mestorozhdeniy v SSSR (The use of a tritium indicator for monitoring the development of oil fields in the USSR),  Ser. Neftyanaya promyshlennost', Moscow: Publ. of ,VNIIOENG, 1982, V. 1(25), 39 p.

2. Morozov O.N., Andriyanov M.A., Koloda A.V. et al., Use of intelligent tracer technology for inflow monitoring in horizontal producers of the Prirazlomnoye oilfield (In Russ.), Ekspozitsiya Neft' Gaz, 2017, no. 7 (60), pp. 24–29.

3. Hartvig S.K., Huseby O., Yasin V. et al., Use a new class of partitioning tracers to assess EOR and IOR potential in the Bockstedt field, Proceedings of IOR 2015 – 18th European Symposium on Improved Oil Recovery, Apr. 2015, DOI: https://doi.org/10.3997/2214-4609.201412118.

4. Sanni M., Al-Abbad M., Kokal S., Dugstad O., Hartvig S., Huseby O., Pushing the envelope of residual oil measurement: a field case study of a new class of inter-well chemical tracers, SPE-181324-MS, 2016, DOI: https://doi.org/10.2118/181324-MS.

5. Huseby O., Galdiga C., Zarruk G.A. et al., New tracers to measure residual oil and fractional flow in push and pull tracer tests, SPE-190421-MS, 2018, DOI: https://doi.org/10.2118/190421-MS.

6. Mingazov M.N., Strizhenok A.A., Anoshina M.M. et al., Utochnenie geologicheskogo stroeniya i prognoz treshchinovatosti bashkirskikh otlozheniy Vishnevo-Polyanskogo mestorozhdeniya (Clarification of the geological structure and prediction of fracturing of the Bashkir deposits of the Vishnevo-Polyanskoye field), Proceedings of TatNIPIneft' / OAO “Tatneft'”, 2014, V. 82, pp. 52–58.

7. Mingazov M.N., Strizhenok A.A., Kamyshnikov A.G. et al., Izuchenie neodnorodnosti verkhnepermskikh otlozheniy Ashal'chinskogo mestorozhdeniya sverkhvyazkoy nefti (Study of the heterogeneity of the Upper Permian deposits of the Ashalchinskoye super-viscous oil field), Proceedings of TatNIPIneft' / OAO “Tatneft'”, 2015, V. 83, pp. 307–312.

8. Kubarev P.N., Kamyshnikov A.G., Kondakov S.V., Primenenie mnogoindikatornogo metoda issledovaniya mezhskvazhinnogo prostranstva na ob"ektakh PAO “Tatneft'” (Application of the multi-indicator method for studying the interwell space at the facilities of Tatneft PJSC), Proceedings of scientific and technical conference dedicated to the 60th anniversary of TatNIPIneft PJSC Tatneft, Bugul'ma, 13-14 April 2016, Naberezhnye Chelny: Ekspozitsiya Neft' Gaz Publ., 2016, pp. 145–149.

9. Antonov G.P., Abramov M.A., Kubarev P.N., Carrying out tracer studies to control and regulate the process of waterflooding of oil deposits at Tatneft (In Russ.) Inzhenernaya praktika, 2015, no. 5, pp. 56–68.

10. Mingazov M.N., Strizhenok A.A., Fatkhullin R.R. et al., Experience on applying indicative studies for hydrodynamic relations between Sakmarian and Upper Permian deposits in Ashalchinsky field of heavy oil (In Russ.), Georesursy = Georesources, 2015, no. 1, pp. 29–32.

11. Molaei M.J., A review on nanostructured carbon quantum dots and their applications in biotechnology, sensors, and chemiluminescence, Talanta, 2019, V. 196, pp. 456-478, DOI:  https://doi.org/10.1016/j.talanta.2018.12.042.

12. Mintz K.J., Zhou Y., Leblanc R.M., Recent development of carbon quantum dots regarding their optical properties, photoluminescence mechanism, and core structure, Nanoscale, 2019, V. 11, no. 11, pp. 4634-4652, DOI:  https://doi.org/10.1039/C8NR10059D.

13. Devi P., Rajputa P., Thakurab A. et al., Recent advances in carbon quantum dot-based sensing of heavy metals in water, TrAC Trends in Analytical Chemistry, 2019, V. 114, pp. 171–195, DOI:  https://doi.org/10.1016/j.trac.2019.03.003.

14. Xuejiao Chen, Fuchun Gong, Zhong Cao et al., Highly cysteine-selective fluorescent nanoprobes based on ultrabright and directly synthesized carbon quantum dots, Analytical and Bioanalytical Chemistry, 2018, V. 410, no. 12, pp. 2961–2970, DOI:10.1007/s00216-018-0980-3

15. Ellis E.S., Al'-Askar M., Khotan M. et al., Saudi Aramco studies nanoparticle oil tracers in Ghawar field, Oil&Gas Journal Russia, 2017, no. 12 (122), pp. 64–69.

Variety of producing field conditions and engineering challenges facing oil and gas producers necessitate development and implementation of innovative solutions based on scientific advances, including geomechanics development. In view of the problems to solve, Tatneft Company has decided to develop its own software for geomechanical simulation. This software will make it possible to consider specific features of productive formations at Tatneft’s assets, to meet the requirement for improved quality of operations digitization, to provide import substitution, and to reduce possible risks of sanction restrictions.

The paper presents the first results of developing proprietary software for geomechanical simulation. The software package includes traditional 1D modeling tools, such as calculation of pore pressure and borehole stability, determining safe mud weight range, as well as a complete set of 3D modeling tools, including geological modeling tools and 3D stress-strain behavior calculation considering over-passed elastic yield. It also has an interface for changing stress-strain properties depending on temperature and pressure. The geomechanical model helps to identify the impact of changing in-situ stress state and stress-strain properties on the reservoir rock, overlying and basement rocks during the development process, as well as to establish reservoir production conditions that will eliminate any adverse effects on ultimate oil recovery. Pilot testing of the developed software is currently being underway at Tatneft’s assets to obtain feedback from the technicians who use the results of geomechanical simulation in practice.

References

1. Eaton B.A., Graphical method predicts geopressures worldwide, World Oil, 1976, V. 183, no. 1 (July), pp. 100–104.

2. Zoback M.D., Reservoir geomechanics, Stanford University, California, 2007, https://doi.org/10.1017/CBO9780511586477.

3. Jaeger J.C., Cook N.G.W., Zimmerman R.W., Fundamentals of rock mechanics, Oxford: Blackwell Publishing Ltd., 2007, 475 p.

Steam injection has become a common method of extracting heavy crude oil. To mitigate environmental impact associated with disposal of large volumes of produced water in the heavy oil fields and to decrease the need in fresh water from surface sources, the Company has been using the produced water for steam generation. Currently, Tatneft PJSC operates two water treatment units, the Kamenka unit with the capacity 350 m3/h and the Karmalka unit with the capacity 700 m3/h to produce demineralized water to be used as feed water for steam generation. Membrane methods of water treatment and demineralization have been realized in the above-mentioned water treatment units. The flow scheme includes the following process units and operations: sorption-filtration unit (preliminary cleaning to remove residual oil); ultrafiltration membrane unit (removal of oil); activated carbon sorption filters (further removal of dissolved oil and organic matter); reverse osmosis membranes – two stages (demineralization of water); anionic filters (removal of hydrosulfides); hydrogen peroxide dosing unit (complete removal of sulfide ions). TatNIPIneft R&D Institute has performed extensive studies to develop an efficient technology of preliminary cleaning of produced water in the sorption-filtration unit; also, TatNIPIneft research engineers have carried out studies on hydrogen peroxide dosing into demineralized water to neutralize residual sulfide ions, and have designed an automatic hydrogen peroxide dosing unit. The performed pilot tests allowed to select the most efficient agents for chemical washing of the reverse osmosis membranes. Successful operation of the first-in-Russia water treatment units based on the membrane methods has demonstrated that water meets the requirement to feed water for water-tube units for steam generation.

References

1. Buslaev E.S., Kudryashova L.V., Magsumova R.S., Ratsional'noe ispol'zovanie vodnykh resursov pri razrabotke mestorozhdeniy sverkhvyazkoy nefti (Rational use of water resources in the development of super-viscous oil deposits), Proceedings of Scientific and Technical Conference dedicated to the 60th anniversary of TatNIPIneft, 13-14 April 2016, Naberezhnye Chelny: Publ. of Ekspozitsiya Neft’ Gaz, 2016, pp. 438–439.

2. Heins W.F., McNeill R., Vertical-tube evaporator system provides SAGD-quality feed water, World Oil, 2007, V. 228, no. 10, pp. 135–144.

3. Heins W.F., Technical advancements in SAGD evaporative produced water treatment, Journal of Canadian Petroleum Technology, 2009, V. 48, no. 11, pp. 27–32.

4. Minnich K., Neu D., Evaporator choice critical for effective steam production in SAGD operations, Oil & Gas Product News, 2008, V. 12, no. 3, pp. 22–23.

5. Buslaev E.S., Loyko A.V., Itskov S.V., Sakhabutdinov R.Z., Abramov M.A., Issledovanie svoystv poputno dobyvaemoy vody na mestorozhdeniyakh sverkhvyazkoy nefti i razrabotka tekhnologii ee podgotovki dlya povtornogo ispol'zovaniya (Investigation of the properties of associated water in super-viscous oil fields and development of technology for its preparation for reuse), Proceedings of TatNIPIneft' / PAO “Tatneft'”, 2016, V. 84, pp. 247–254.

6. Voikina G.R., Stratilatova I.V., Magsumova R.S., Nurutdinov A.S., Khabibullin I.Ya., Osobennosti fiziko-khimicheskikh svoistv poputno dobyvaemykh vod mestorozhdeniy sverkhvyazkoi nefti PAO Tatneft (Characteristics of physicochemical properties of associated water in heavy oil fields of PJSC TATNEFT), Proceedings of TatNIPIneft' / PAO “Tatneft'”, 2017, V. 85, pp. 392–395.

7. Garifullin R.M., Anufriev A.A., Sakhabutdinov R.Z., Shatalov A.N., Antonova N.V., Akhmadullin R.R., Issledovaniya metodov ochistki poputno dobyvaemoi vody Ashalchinskogo mestorozhdeniya ot serovodoroda (Research into methods for hydrogen sulfide removal from produced water in the Ashalchinskoye field), Proceedings of TatNIPIneft' / PAO “Tatneft'”, 2011, V. 79, pp. 295–302.

8. Patent RU 2 704 664 C1, System for arrangement of heavy oil and natural bitumen deposit, Inventors: Kudryashova L.V., Gubaydulin F.R., Sakhabutdinov R.Z., Nurutdinov A.S., Arsent'ev A.A., Buslaev E.S.

9. Patent RU 2 720 719 C1, System for arrangement of heavy oil and natural bitumen deposit, Inventors: Gubaydulin F.R., Kudryashova L.V., Antonov O.Yu., Nurutdinov A.S., Arsent'ev A.A.

To ensure the produced oil meets the quality requirements, all chemical agents used in the process of oil production are checked for content of organic chlorine compounds. TatNIPIneft Institute has developed a procedure based on X-ray fluorescence analysis for prompt determination of organochlorine compounds in chemicals’ samples using spectral scanning wavelength-dispersive X-ray fluorescence analyzer, Spectroscan CLSW. The technique allows to measure a mass fraction of organic chlorine compounds in the chemical sample. If the chemical sample (which is an organic-based composition) is a water-based composition, both organic and inorganic chlorine compounds might be present in it. It has been offered to extract organochlorine compounds to isooctane or hexane and to determine the mass fraction of organic chlorine in the extract. The similar approach is used for analysis of hydrochloric acid or HCl-based compositions’ samples. The outcome of the X-ray fluorescence analysis is total content of organic chlorine compounds in the chemical agent sample, including highly volatile forms. Gas chromatography-mass spectrometry method is used to determine the content of organic chlorine in highly volatile organochlorine compounds, as well as the type of these compounds. Shimadzu gas chromatograph/mass spectrometer is used for the purpose. The chromatography-mass spectrometry procedure is detailed in the “Procedure for measurement of mass fraction of volatile organochlorine compounds in chemical agents using gas chromatography method with mass-selective detection”. Combination of two approaches to determine the content of organic chlorine compounds in samples optimizes the costs. In some corrosion inhibitors or bactericides, etc., chlorine compounds are present, which are not classified as organochlorine compounds, but when heated, they are decompounded forming organochlorine compounds. For example, alkyldimethylbenzylammonium chloride when heated is decompounded forming benzyl chloride. To assess chemical agents’ stability to decompounding, a thermal stability test is performed. Chemical agent with the dosage corresponding to the actual chemical concentration in field is added into a synthetic emulsion that was obtained from oil without organochlorine compounds and mineralized water. The emulsion is dehydrated, naphta is distilled form of oil, and the content of organic chlorine in the distilled naphta is determined in accordance with GOST Р 52247-2004, Method В.

Integrated approach to chemical agents control helps to avoid purchase of chemical agents containing organochlorine compounds, thus, ensuring that stock-tank oil quality meets the requirements of regulatory documents.

References

1. Nadirov N.N., Kotova A.V., Kamyanov V.F. et al., Metally v neftyakh (Metals in crude oil), Alma-Ata: Nauka Publ., 1984. 448 p.

2. Zulfugarly D.I., Kuklinskiy A.N., Orlenko S.F., Pushkina R.A., Metalloporphyrin complexes in Paleozoic oils in Volgograd region (In Russ.), Azerbaijanskiy Khimicheskiy Zhurnal, 1976, no. 6, pp. 17-21.

3. Koblova A.Z., Kalashnikova I.G., Belokon T.V., Yakovets Yu.A., Zakonomernosti raspredeleniya porfirinov v neftyakh i vo vmeshchayushchikh nefti geologicheskikh obrazovaniyakh (Trends of porphyrins distribution in oils and in host rocks), Proceedings of All-USSR Conference on Chemistry and Geochemistry of Porphyrins, Dushanbe, 1977, p. 37.

4. Khutoryanskiy F.M., Izbrannye trudy (Selected papers), Ufa: Publ. of  GUP INKhP RB, 2013, 672 p.

5. Karaulova E.O., Levchenko D.N., Sosnina N.P., Podobaeva T.P., Investigation of organochlorine compounds of oil (In Russ.), Khimiya i Tekhnologiya Topliv i Masel, 1981, no. 6, pp. 47-48.

6. Levchenko D.N., Bergshtein N.V., Nikolaeva N.M., Tekhnologiya obessolivaniya neftei na neftepererabatyvayushchikh predpriyatiyakh (Oil desalting technology at oil refineries), Moscow: Khimiya Publ., 1985, 168 p.

7. Azarova S.N., Problem of chlorine in processing industry (In Russ.), Neftegazovaya Vertikal, 2002, no. 8, pp. 50-51.

8. Patent RU 2 740 991 C1, Method of determining content of organic chlorine in chemical reagents used in oil production, Inventors: Tatyanina O.S., Gubaidulin F.R., Sudykin S.N., Abdrakhmanova L.M.

9. Tatyanina O.S., Gubaidulin F.R., Sudykin S.N., Zhilina E.V., Gubaidulina R.I., Issledovanie vliyaniya khimicheskikh reagentov, primenyaemykh v sisteme neftedobychi, na obrazovanie khlororganicheskh soedineniy v nefti (Investigation of impact of chemical agents used in oil production process on forming of organochlorine compounds in oil), Proceedings of TatNIPIneft, Tatneft PJSC, 2020, V. 88. pp. 266-268.

10. Patent RU 2 734 582 C1, Method of determining stability of chemical reagents used in an oil production system, to decomposition with formation of volatile organochloride compounds, Inventors: Tatyanina O.S., Gubaidulin F.R., Sudykin S.N., Urazova A.V. 

Economic efficiency, and in some cases, the overall feasibility of field development with application of water injection system is critical in present-day conditions. However, economic efficiency, in its turn, consists of at least two main interrelated factors: energy efficiency and reliability. Improving energy efficiency is a sophisticated problem that involves extensive measures regarding process flow diagrams, methods, processes and equipment, mostly pumping equipment. However, equipment reliability is also a challenging task, closely related to energy efficiency and having a significant impact on the process cycle and sustainability of operational procedures. State-of-the-art water-injection and oil-gathering technologies impose strict requirements to pumping equipment reliability. In its turn, equipment reliability is based on obligatory application of advanced control and maintenance techniques and requires a comprehensive approach to solving engineering and technical problems. Ensuring successful operation of pumping equipment in water-injection system over a long period of time implies a zero-tolerance approach to selection of equipment design and materials based on  physical and chemical properties of the liquid to be pumped, as well as site conditions, with due regard for possible seasonal changes in pumping characteristics; proper equipment installation, positioning, and operation as required by the service manual; possibility of diagnosing at stated intervals, but ideally, continuous monitoring of changes in pumping parameters and early pre-emergency warning. In case of failure, the cause must be carefully investigated and certain steps must be taken to identify the root cause of the problem in order to prevent its recurrence, which imposes certain requirements to the skills of the operating staff. Pumping equipment of water-injection and oil-gathering systems very rarely has emergency failures if it is properly installed, dynamically balanced, mounted on a specified base with acceptable alignment, properly lubricated, started, operated and stopped as required by the operating instructions, and if well-qualified personnel monitor any deviations in parameter values. However, evaluation of the equipment efficiency is rather challenging. One of the parameters for such evaluation is cost of ownership.

The paper considers various approaches to equipment maintenance, discusses distribution of pump failure sources in water-injection and oil-gathering systems based on practical knowledge, and considers the issue of estimating owning cost and differences in its specific values. Key factors for the development of reliability technology are presented.

References

1. Konnov V.A., Fattakhov R.B., Abramov M.A., Application of positive displacement plunger-type pumps in reservoir pressure maintenance systems (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2019, no. 1, pp. 62–65, DOI: 10.24887/0028-2448-2019-1-62-65.

2. Gabdrakhmanov R.A., Mitrofanov E.L., Konnov V.A., Krasnov O.M., Application of non-positive and positive displacement pumps in water injection system: challenges and opportunities (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 7, pp. 56–59, DOI: 10.24887/0028-2448-2020-7-56-59

3. Starkin I.N., Improving energy efficiency of water-injection system. Experience of high-capacity pump implementation (In Russ.), Inzhenernaya praktika, 2018, no. 9, pp. 60–66.

4. Chikin V.V., Nilov R.V., Islamov I.I. et al., Criteria of a choice of the optimum pump equipment for increase of energy efficiency of system of maintenance of reservoir pressure on objects of Gazpromneft-Muravlenko Branch (In Russ.), Neftyanoe khozyaystvo = Oil Industry,  2015, no. 12, pp.  71–73.

Plugging of sucker-rod pump’s valves with solids, wax, floating debris, etc. while well operation are an expensive and a time-consuming challenge. The available downhole equipment does not allow for direct washing of the pump’s valves, while backwashing is often ineffective, because of settling of suspended particles in the pump and because of circulation losses. The currently used downhole pumping equipment can only be used for bottomhole zone treatment in wells with tubing sucker-rod pumps. A modified sucker-rod pump can solve two tasks simultaneously: well servicing with direct washing of the valve assembly and bottomhole zone treatment without inviting workover crews. This will increase the time between repairs and decrease OPEX associated with wellbore intervention jobs.

The sucker-rod pump design comprises conventional assemblies and components, save a modified suction valve assembly. The latter is equipped with a mechanism of displacement of the ball of the valves pair when the plunger is submerged below the bottom end of the stroke until stop. Successful rig tests, followed by field tests in two Tatneft PJSC wells confirmed performability of the modified sucker-rod pump. During field operation, two operation modes were tested: a) direct pumping of fluid by complete unloading of the rod string; b) pump discharge with testing of traveling and standing valves for leakage. This paper presents a detailed description of the sucker-rod pump design, the procedure and the results of the field tests.

Climate change is a global environmental problem of the 21st century. The reason for changes in the atmosphere thermal conditions is increase in CO2 atmospheric loading, specifically, due to human activity. A European society has announced its commitment to total decarbonization and upcoming introduction of a cross-border carbon tax. These actions indicate that the climate change issue raised by scientific and political community has passed from the theoretical area to the practical one exerting an impact on business. Tatneft Company recognizes the importance of community demand for green energy to reduce greenhouse gas emissions, and pays due consideration to fundamental changes in utility balance towards less carbon-intensive fuels. Having signed a Memorandum of cooperation with the National network of United Nations Global Compact, Tatneft has set a primary objective of sustainable development No.13 named Combating climate change. To accomplish this objective, the Company plans to execute the following projects: efficient greenhouse gas emission management; search for and implementation of process solutions to reduce direct and indirect emissions; improving production energy efficiency; green energy sector development; study of carbon capture and storage (CCS) technology applicability at Tatneft’s assets; implementation of mitigation actions; climate cooperation. 

Tatneft has approved a revised version of Company Environmental policy considering climate change. The Company has set goals to reduce greenhouse gas emissions at its assets, and has established a liability and incentive system for attaining these goals. Accounting of greenhouse gas emissions in the Company complies with the requirements of Russian legislation and international recommendations. An internal greenhouse gas emissions charge has been established. The Сompany implements a Program of carbon footprint reduction and production energy efficiency increase. Currently, the Company uses solar panels, pellet heating systems, and small-scale hydropower plants. Tatneft plans to expand share of renewable energy sources in in-house power generation through wind power projects, downhole power generation, and more extensive use of solar energy. The CCS  project is the key to achieving carbon neutrality. CO2 emissions from flue gases coming from TANECO and Nizhnekamsk heat power plant are planned to be used for enhanced oil recovery and underground storage. Mitigation actions are implemented under Circulating Forest Project and Reforesting Program. In 2021, the company plans to plant 5 million seedlings!

TATNEFT is boosting cooperation in climate matters with the parties concerned including government agencies, international and Russian industry associations, companies, investors and financial organizations. The Company is open to cooperation in the field of de-carbonization.

References

1. Tseli v oblasti ustoychivogo razvitiya OON (Objectives in the field of sustainable development), URL: https://www.un.org/sustainabledevelopment/ru/.

2. Doklad ob osobennostyakh klimata na territorii Rossiyskoy Federatsii za 2020 god (2020 Report on climate pattern in Russia), Moscow: Publ. of Federal Service for Hydrometeorology and Environmental Monitoring (Rosgidromet)), 2021, 104 p., URL: https://www.mnr.gov.ru/press/news/rosgidromet_opublikoval_doklad_ob_osobennostyakh_klimata_v_rossii_...

3. Tekhnologicheskiy obzor. Ulavlivanie, ispol'zovanie i khranenie ugleroda (SSUS) (Carbon capture, use and storage (SSUS): technical review), UN Economic Commission for Europe. 36 p., URL: https://unece.org/publications/tekhnologicheskiy-obzor-ulavlivanie-ispolzovanie-i-khranenie-ugleroda...

This article is devoted to the structural features of the OI-II formation at the Srednebotuobinsky oil-gas condensate field, which is one of the largest oil fields in Eastern Siberia. The field was discovered 50 years ago. The main target are the ancient Vendian sandstones of the Botuoba horizon. The production started in 2013. The second largest reservoir is the OI-II formation, but this object is still at the stage of exploration. Exploration of the field has been conducted since the 1970s, but no commercial oil inflows have been received from the Osinskian horizon (OI-II formation). The formation has a complex and heterogeneous geological structure, and for a long time there was no understanding which zones are associated with the existing commercial inflows in several wells, as well as how these zones can be predicted for the purposes of production drilling. However, thanks to the integrated approach to the study of deposits used in Rosneft Oil Company, it was possible to identify patterns of distribution of zones of improved reservoir properties, map these zones and test them using horizontal drilling. This project shows how important it is to use all available research tools – borehole data with an extended log complex, 3D seismic data, core data with a detailed sedimentological description. The Scientific Center of Rosneft RN-Exploration LLC proposed wells for re-testing and drilling for the OI-II formation, and the subsidiary company Taas-Yuryakh Neftegazodobycha LLC supported this initiative and carried out work on the field. Based on the results of successful tests a further research program was formed, which was successfully approved by Rosneft. The work methodology developed at the project can be applied to other similar objects in the Eastern Siberia.

Mudlogging while drilling is a combination of three pre-existing individual types of surveys – gas logging, express petrophysical analysis and measurement while drilling. Efficiency and safety of drilling are mainly determined by quality of mudlogging that has taken a more important role over the last years.  On many occasions, mudlogging results helped discover new deposits of hydrocarbons in unconventional traps and reservoirs. A distinctive feature of mudlogging is that it examines core, cuttings, drilling mud, and gas that carry direct geological information about the studied section, which gives special significance and importance to this type of work. Accuracy of obtaining and processing mudlogging data will determine the order of pay zone penetration that, in turn, affects efficiency of oil production and overall future operation of the field. In comparison with classical geophysical methods, mudlogging while drilling gives an opportunity to get close to real-time information.

The article describes key objectives, methods and technologies of mudlogging while drilling and presents a structure of mudlogging methods from standard to high-tech logs. Special attention is paid to the integrated approach to forming a mudlogging program based on well type and preset geological and technical objectives. The authors give a specific example to illustrate introduction of modern technologies to improve control and safety of drilling operations at the Rosneft Oil Company license areas.

References

1. RD 153–39.0–069–01. Tekhnicheskaya dokumentatsiya po provedeniyu geologo-tekhnologicheskikh issledovaniy neftyanykh i gazovykh skvazhin (Technical documentation for conducting geological and technological studies of oil and gas wells).

2.  Luk'yanov E.E., Strel'chenko V.V., Geologo-tekhnologicheskie issledovaniya v protsesse bureniya (Geological and technological research in the process of drilling), Moscow: Neft' i gaz Publ., 1997, 688 p.

3. Al'temirov D.V., The main tasks of geological and technological research of wells while drilling (In Russ.), Molodoy uchenyy, 2017, no. 3, pp. 207-209.

4. Luk'yanov E.E., Geologo-tekhnologicheskie i geofizicheskie issledovaniya v protsesse bureniya (Geological, technological and geophysical surveys while drilling.), Novosibirsk: Istoricheskoe nasledie Sibiri Publ., 2009, 752 p.

5. Chirkov V.Yu., Kozhevnikov I.S., Kuznetsov I.V., Underestimated informative parameters of geological and technical research (In Russ.), Nefteservis, 2013, no. 4(24), pp. 43–45.

One of the main conditions for ensuring high-quality well cementing is full replacement of fluid in the annular space, which can be achieved, among other things, by ensuring the concentric position of the casing string in the wellbore. The algorithms based on ISO 10427-2: 2004 are usually used to calculate the centralizer placement for ensuring a required eccentricity. The formulas presented in ISO 10427-2: 2004 are only applicable for calculating casing deflection between two identical centralizers. It is assumed that if the deflection of the string between the two centralizers exceeds the nominal value of the gap between the string and the wellbore wall, then the eccentricity over the entire interval between the centralizers is equal to one. At the same time, actual measurements in wells using downhole GR-density fault detector show that the eccentricity of the casing strings extremely rarely turns into one.

In the paper the new approach to casing eccentricity calculation is suggested. It considers the possible sagging of the casing between two adjacent collars. First, the deflection between two nearest centralizers is determined. The calculating procedure of casing deflection at each point will depend on the resultant gravity force, Archimedes' force, tensile force and bending force. If centralizers are installed on each casing, then the maximum deflection and therefore the minimum clearance will be noted in the middle of each casing. If the gap in the middle of the distance between the centralizers exceeds the half-difference between the outer diameters of the collar and the pipe body, then it is considered that the collar does not touch the borehole wall. Otherwise, an additional fulcrum appears in the middle between the two centralizers. If there are more than two casing between the centralizers, then in this case there are several likely outcomes: all collars touch the wellbore walls, all collars do not touch the wellbore walls, only some collars touch the wellbore walls. The calculation of the casing deflection between two collars or between the collar and the centralizer is carried out in the same way as the calculation of the casing deflection between two centralizers. It is shown that the procedure that has been described leads to more accurate eccentricity prediction in comparison with existing ones. The proposed approach was implemented in specialized software for centralizer placement calculation in Surgutneftegas PJSC.

References

1. ISO 10427-2:2004. Petroleum and natural gas industries. Equipment for well cementing. Part 2: Centralizer placement and stop-collar testing.

2. Juvkam-Wold, H.C., Baxter, R.L., Discussion of optimal spacing for casing centralizers, SPE-13043-PA Drilling Engineering, Dec. 1988,   https://doi.org/10.2118/13043-PA.

3. Juvkam-Wold H.C., Wu J., Casing deflection and centralizer spacing calculation, SPE-21282-PA, 1992, https://doi.org/10.2118/21282-PA.

4. Kinzel H., Kiithan T., Planning the cementing job incorporates data management and technical expertise – A new software to calculate the optimum placement of mechanical cementing products, SPE-38130-MS, 1997, https://doi.org/10.2118/38130-MS

5. Blanco A., Ciccola V., Limongi E., Casing centralization in horizontal and high inclined wellbores, SPE-59138-MS, 2000, https://doi.org/10.2118/59138-MS

Poorly consolidated reservoir development process is followed by complications that are related to sand production. The development of such reservoir requires strict control over the rock failure of the bottomhole zone. Rock failure at the bottom of a well occurs due to the reason of the irreversible deformation occurrence. Consequently, reservoir rock loses its integrity due to the influence of critical stress level. Thereby, one of the main aims of geomechanical modeling is the evaluation of the well critical drawdown with the aim of prevention of the sand production and assurance of the borehole wall stability. This paper provides a detailed description of the critical drawdown evaluation tool. The evaluation was performed by two methods. In the case of a simplified criterion, it is possible to obtain a continuous drawdown profile in a well of a given orientation, while a full-fledged criterion at a given drawdown is used to estimate the rock failure zone. The current approach was implemented in Python programming language that allows to quickly and efficiently carry out calculations for a group of wells simultaneously. Evaluation of stress-strain state was performed for both initial reservoir conditions and preassigned time step for the reservoir pressure. Thus, for a well of any orientation, based on data from one-dimensional geomechanical modeling, the critical drawdown is calculated for two variations of strength criteria, taking into account changes in reservoir pressure. The demonstrated approach allowed to obtain the critical drawdown profile in the well considering the change in reservoir pressure. Calculations were carried out for several wells, and appropriate recommendations were formed on the bottomhole pressure for a given period of well production.

References

1. Fjær E, Holt RM, Horsrud P, Raaen AM, Risnes R., Petroleum related rock mechanics, V. 53, Elsevier, 2008.

2. Jaeger J.C., Cook N.G.W., Zimmerman R.W., Fundamentals of rock mechanics, Blackwell, 2007, 475 p.

3. Papamichos E., Furui K., Sand production initiation criteria and their validation, Proceedings of 47th US Rock Mechanics / Geomechanics Symposium, 2013, pp. 198–206.

4. Papamichos, E., Furui, K., Analytical models for sand onset under field conditions, Journal of Petroleum Science and Engineering, 2018, doi: 10.1016/j.petrol.2018.09.009

In research and scientific-technical publications, the matters of selecting the optimal parameters for the unsteady stimulation technology usually refer to determine the parameters of the reservoir pressure maintenance system. It is only in recent times, the studies and technologies for applying the unsteady (cyclic) operation of producers for increasing the oil recovery from layerwise heterogeneous reservoirs started to appear. This article describes the processes to change the profiles of pressure and saturation in the layerwise permeably heterogeneous reservoir for modelled zone during the unsteady operation of producers. Based on hydrodynamic modelling of intermittent operation of a production horizontal well, which produces from layerwise non-uniform permeable formation with highly viscous oil, it is shown, that in the layerwise heterogeneous porous reservoir with a significant non-uniformity of permeable area along the cross section, an intermittent production of a horizontal well leads to an increased oil rate and some reduced water cut of produced products. Despite positive increment in oil flowrate during intermittent well operation, the rate of oil reserves recovery reduces due to idle time, cumulative oil production is below the base value. Increment value of oil flowrate during intermittent well operation depends on its “initial” water cut. It is found that, the higher the “initial” water cut, the lower the oil flowrate increment during intermittent production. Once the intermittent flooding is complete, the well remains higher (in comparison to the base level) oil flowrate for a limited period of time, however, after a while the oil flowrate reduces below the base level or equals it, while the water cut goes up to the base level and in certain cases above it. It is shown, that the intermittent (cyclic) water flooding in the production well influences the neighbouring wells, and this effect depends on mutual location of production and injection wells. It is found, that the changes in the process parameters of “remote” wells during intermittent operation of the neighbouring wells, mostly relates not to the unsteady stimulation (even though there is some effect), but to the increase of the reservoir pressure in an inter-well area and to the directional change of filtration flows by the lateral. Besides, the intermittent operations of the well leads both to occurrence of interlayer cross-flows of reservoir fluids and to the change of flow direction by lateral (more intense production from the reservoir area between the producers).

References

1. Gafarov Sh.A., Faizov R.G., Kabirov M.M., Povyshenie effektivnosti tsiklicheskogo vozdeystviya na neodnorodnye neftyanye plasty (Improving the efficiency of cyclic impact on heterogeneous oil reservoirs), Ufa: Monografiya Publ., 2007, 74 p.

2. Vladimirov I.V., Salikhov M.M., Bulgakov R.R. et al., Using data mining methods in searching objects for successful application of non-stationary waterflooding technologies (In Russ.), Neftepromyslovoe delo, 2005, no. 2, pp. 26–32.

3. Ibragimov N.G., Khisamutdinov N.I., Taziyev M.Z. et al., Sovremennoye sostoyaniye tekhnologiy nestatsionarnogo (tsiklicheskogo) zavodneniya produktivnykh plastov i zadachi ikh sovershenstvovaniya (The current state of unsteady (cyclic) flooding technology and problems of their improving), Moscow: Publ. of VNIIOENG, 2000, 112 p.

4. Ivanov A.N., Pyatibratov P.V., Aubakirov A.R., Dzyublo A.D., Justification of injection wells operating modes for cyclic waterflooding application (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 2, pp. 28–31.

5. Manapov T.F., Optimizatsiya i monitoring razrabotki neftyanykh mestorozhdeniy (Optimization and monitoring of oil field development), Publ. of VNIIOENG, 2011, 296 p.

The technological approach to well testing of prospecting and exploratory wells in the casing in the flowing mode has been well studied and is technically simple to implement. However, in case of non-overflowing flow regime well the testing process become significantly complicated and requires the involvement of a larger number of technical means. The «gas lift + level build-up curve (LBC) / inflow curve» method assumes the initial inflow stimulation by nitriding / swabbing, test for on pseudo-steady filtration modes (during gas lift), followed by tracing the level build-up curve. This method is primarily considered as a tool for obtaining a minimum set of parameters, such as the type of formation fluid and the volumetric flow rate. However, well testing of non-overflowing marginal formations using this method has a number of significant disadvantages, consisting in the limitedness of the obtained hydrodynamic characteristics of the object under study. First of all, this concerns the quality of the assessment of such key parameters as reservoir pressure, permeability of the remote formation zone and the state of the bottomhole formation zone. The main reason for the limitations of the LBC method is the long-term dominance of the effects of the wellbore storage, since at a low flow rate (5–10 m3/day) of oil or formation water, the pressure change depends only on the changing level in the well, according to the dynamics of which, it is often impossible to identify the response of the formation. The currently available approaches to the interpretation of the  LBC do not give a conclusive assessment, due to the fact that when performing key stages of processing, a priori knowledge of the reservoir pressure parameter is required, the iterative selection of which can lead to significant errors in the results.

The approach to well testing given in the article by the inflow performance relationship curve + pressure build-up curve, implemented by means of a hydraulic jet pump arrangement, makes it possible to neutralize the complicating effects of the wellbore storage. In this paper, the authors highlight the results of comparing the quality assessment of well tests when testing low-flow oil-saturated reservoirs with a non-overflow inflow using the "Swabbing + LBC", as well as of the tests with the usage of jet pump assemblies. The article presents the key technological aspects of testing with the emphasis on the advantages and disadvantages of both methods.

References

1. Kremenetskiy M.I., Ipatov A.I., Gulyaev D.N., Otsenki produktivnykh svoystv plasta i skvazhiny po gidrodinamicheskim issledovaniyam (Estimates of the productive properties of the formation and wells based on hydrodynamic studies), Moscow: Publ. of Gubkin University, 2003, 86 p.

2. Houzé O., Viturat D., Fjaere O.S., The theory and practice of pressure transient and production analysis & The use of data from permanent downhole gauges, URL: https://www.kappaeng.com/documents/flip/dda51001/files/ assets/basic-html/page-1.html

3. Zeyn Al'-Abidin M.D., Sovershenstvovanie metodov interpretatsii dannykh gidrodinamicheskikh issledovaniy skvazhin s gorizontal'nym okonchaniem (Improvement of methods for interpretation of hydrodynamic test data of wells with horizontal completion): thesis of candidate of technical science, Tyumen, 2017.

The article presents an analysis of the conducted hydrodynamic and field geophysical survey as of 09/01/2020 multilateral horizontal wells within the perimeter of Rosneft Oil Company. The main problems in conducting field geophysical survey and interpreting its results are considered: a decrease in the information content of research, difficulties in specifying the zone of water inflow, low coverage of the fund's research. In order to increase the information content and increase the coverage of production logging, the article describes the positive experience of using Y-tool equipment and alternative methods (a device for interval monitoring of the inflow and fiber-optic pressure, temperature and pressure sensors). In the case of multiphase flow stratification in the horizontal section of the well, it is recommended to use a flow meter with distributed propellers over the well section to obtain reliable information. The main problems of well testing in the multilateral horizontal wells were identified: low quality of interpretation assessment, low coverage of studies, high production losses. To increase the reliability of studies, it was proposed to tune the models for the entire production history (increasing the accuracy of estimating permeability and skin factor). With high-quality primary data (daily measurements of pressure and well flow rate), it is recommended to carry out production data analysis, which allows obtaining well and reservoir parameters without long shutdowns, and therefore increasing the coverage of the research fund. Based on the analysis results, two sets of studies (extended and optimal) were proposed for wells during pilot testing and commercial production, which can reduce oil losses without losing information content.

References

1. URL: https://www2.deloitte.com/content/dam/Deloitte/ru/Documents/energy-resources/Russian/oil-gas-survey-....

2. Tulenkov S.V., Machekhin D.S., Vologodskiy K.V. et al., Planning, execution, and interpretation of results of pilot operations on Russkoye heavy oil field (Part 1) (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2013, no. 10, pp. 70–73.

3. Tulenkov S.V., Shirokov A.S., Grandov D.V. et al., Analysis of production data of horizontal oil wells for determination of reservoir flow parameters (In Russ.), Neftyanaya provintsiya, 2019, no. 4(20), pp. 140–156, DOI 10.25689/NP.2019.4.140-15

4. Arzhilovskiy A.V., Zernin A.A., Shirokov A.S. et al., Evaluation of multilateral wells efficiency in the fields of Vankorsky cluster in different geological environments (In Russ.), Nedropol'zovanie XXI vek, 2020, no. 6(89), pp. 64–73.

5. Ipatov A.I., Kremenetskiy M.I., Kleshkov I.S., Buyanov A.V., Experience in the application of distributed fiber optic thermometry for monitoring wells in the company Gazprom Neft (In Russ.), PRONEFTʹ. Professionalʹno o nefti, 2017, no. 3, pp. 55–64.

In order to make economically optimal technical solutions for foundations and foundations, specialists in the field of temperature stabilization of soils must perform predictive heat engineering calculations. In the process of designing long-distance objects (field and main pipelines in the above-ground version, overhead power lines), the number of engineering-geological wells for which it is necessary to perform predictive heat engineering calculations can exceed several hundred pieces. To speed up the design procedure, without losing the accuracy of the results of numerical modeling of the thermal state of permafrost soils of the foundations of structures, allows the typification of engineering-geological and geocryological conditions.

In this article, an algorithm for typing engineering-geological and geocryological conditions is proposed and considered. Based on the results of numerical modeling, the scientific validity of the application of the proposed algorithm has been proved. An analysis of the optimization of working resources is carried out, provided that the algorithm is introduced into the process of designing linear structures for the construction of the surface infrastructure of oil and gas, gas and oil and gas condensate fields in the conditions of the spread of permafrost soils. The algorithm is based on the principle of analyzing the lithological composition, physical-mechanical and thermophysical properties of soils, the initial temperature state of soils (plastic frozen, frozen, solid-frozen, thawed) and the type of section (thawed, continuous, non-melting or buried roof of permafrost soils). According to the results of the analysis, geotechnical wells with similar soil parameters are combined into typical geotechnical conditions for which it is assumed that the dynamics of the temperature field change will be identical. The typification process is an important practical tool for a specialist in the field of predictive heat engineering calculations working with long-distance objects (field and main pipelines, high-voltage power lines). The introduction of automated software algorithms in the design can significantly reduce the time for performing numerical modeling without losing the accuracy of the results.

References

1. Ipatov P.P., Regional'naya inzhenernaya geologiya: uchebnoe posobie (Regional engineering geology), Tomsk: Publ. of TPU, 2007, 140 p.

2. Zakharov M.S., Sistemnyy analiz v regional'noy inzhenernoy geologii (Systems analysis in regional engineering geology), Leningrad: Publ. of LSI, 1980, 89 p.

3. Lomtadze V.D., Inzhenernaya geologiya. Spetsial'naya inzhenernaya geologiya (Engineering geology. Special engineering geology), Leningrad: Nedra Publ., 1978, 496 p.

4. Zavershinskaya D.V., Vybor klassifikatsionnykh priznakov dlya inzhenerno-geologichekoy tipizatsii uchastkov vozvedeniya mostovykh perekhodov v razlichnykh inzhenerno-geologicheskikh usloviyakh (Selection of classification features for engineering-geological typification of sections for the construction of bridge crossings in various engineering-geological conditions), Proceedings of All-Russian scientific and practical youth conference “Sovremennye issledovaniya v geologii” (Modern research in geology), March 25–27, 2016, St. Petersburg, 2016, pp. 106–07.

5. Poverennyy Yu.S., Dubrov A.D., Gilev N.G. et al., Application of a digital model of a linear object for the design of pipelines in the conditions of construction on permafrost soils  (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2020, no. 8, pp. 106–109, DOI: 10.24887/0028-2448-2020-8-106-109.

6. Certificate of official registration of the computer program no. 2020618505 “Svaya-SAPR Pro”, Authors: Medyanik S.S., Kesiyan G.A, Dubrov A.D., Zenkov E.V., Zagumennikova A.V., Poverennyy Yu.S., Fedoseenko V.O., Gilev N.G.

7. Georgiyadi V.G., Zenkov E.V., Zolotukhin K.V., Vliyanie zasolennosti na rezul'taty chislennogo prognoza teplovogo sostoyaniya mnogoletnemerzlykh gruntov na severe Krasnoyarskogo kraya (Influence of salinity on the results of numerical prediction of the thermal state of permafrost soils in the north of the Krasnoyarsk Territory), Proceedings of scientific and practical conference “Informatsionnye tekhnologii, robotizatsiya protsessov pri razrabotke, obustroystve i ekspluatatsii mestorozhdeniy” (Information technology, robotization of processes in the development, construction and operation of fields), Krasnodar, December 11–12, 2019, p. 14.

8. Litvinov T.A., Phase composition of building materials water at negative temperatures (In Russ.), Uspekhi stroitel'noy fiziki v SSSR, 1967, no. 3, pp. 38–46.

9. Starostin E.G., Calculation of the amount of unfrozen water from adsorption isotherms taking into account ice content (In Russ.), Nauka i obrazovanie, 2008, no. 1, pp. 43–48.

10. Grishin A.N., Golovanov A.N., Sukov Ya.V., Experimental determination of technophysical, thermokinetic and filtration characteristics of peat (In Russ.), Inzhenerno-fizicheskiy zhurnal, 2006, V. 79, no. 3, pp. 131–136.

11. Second Roshydromet assessment report on climate change and its consequences in the Russian Federation, URL: https://public.wmo.int/en/media/news-from-members/second-roshydromet-assessment-report-climate-chang...

12. Certificate of official registration of the computer program no. 2021616230 “Tipizatsiya MMG”, Authors: Georgiyadi V.G., Zolotukhin K.V., Zenkov E.V., Poverennyy Yu.S., Fedoseenko V.O., Gilev N.G., Dubrov A.D.

13. Certificate of official registration of the computer program no. 2021616474 “TsMLO”, Authors:  Dubrov A.D., Poverennyy Yu.S., Gilev N.G., Zenkov E.V., Yargunina A.O.

Development of offshore oil and gas fields on the continental shelf is fundamentally different from their development on land. High complexity, specific peculiarities of carrying out and organization of works at sea are determined by various factors, including, first of all, climatic and engineering-geological conditions. The main problems during the development of these fields are caused by high cost and uniqueness of the applied technical means as well as challenges, which are connected with the necessity of works under the water, special technologies of construction organization, ecological safety, etc. The right choice and accuracy of offshore operations have a significant impact on the cost of produced hydrocarbons. Offshore operations are a set of technical and technological activities for transportation, assembly, docking and installation at the point of operation of the offshore oil and gas facility or its components, performed while the object is afloat, or using floating crafts.

The implementation of offshore operations projects in the fields of Vietsovpetro JV is associated with the creation of complex engineering structures both onshore and offshore, the operation of specialized vessels, technical facilities and special equipment. The article describes the stages of oil and gas field development, design, construction, operation, liquidation of offshore facilities and subsea communications of Vietsovpetro JV fields. The characteristics of production conditions, the principle of selection of technical means to perform work both at the onshore construction site and for offshore operations at sea are given.

References

1. Bogoyavlenskiy V.I., Bogoyavlenskiy I.V., Nikonov R.A. et al., Oil and gas potential of the crystalline basement at Southern Vietnam offshore (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2016, no. 8, pp. 98–104.

2. Ty Tkhan' Ngia, Veliev M.M., Le V'et Khay, Ivanov A.N., Razrabotka shel'fovykh neftyanykh mestorozhdeniy SP V'etsovpetro (Pryzhok “Belogo Tigra” dlinoyu v 35 let...) (Development of offshore oil fields by JV Vietsovpetro (Leap of the "White Tiger" 35 years long ...)), St. Petersburg: Nedra Publ., 2017, 386 p.

3. ND no. 2-090601-006. Rossiyskiy Morskoy Registr Sudokhodstva. Pravila razrabotki i provedeniya morskikh operatsiy (Russian Maritime Register of Shipping. Rules for the development and conduct of offshore operations), St. Petersburg, 2017, 162 p.

4. Bulatov A.I., Proselkov Yu.M., Morskie neftegazovye sooruzheniya. Tekhnika i tekhnologiya razrabotki i ekspluatatsii morskikh neftegazovykh mestorozhdeniy (Offshore oil and gas facilities. Engineering and technology for the development and operation of offshore oil and gas fields), Krasnodar: Prosveshchenie-Yug Publ., 2006, 412 p.

5. Suvorova I.A., Morskie neftegazovye sooruzheniya. Vyvod iz ekspluatatsii (Offshore oil and gas facilities. Removal from service), Moscow: Publ. of Gubkin University, 2007, 110 p.

The paper describes the application of modern digital technologies combined within the framework of complex approach during the bringing the oil wells equipped by electrical submersible and sucker rod pumps on to stable production. On the base on the expert rules, digital twins and methods of machine learning the uniform decision support system is developed, which allows to support the process of bringing the well on to stable production beginning from preparation the oil well to startup and finishing when it goes to the normal production. The set of intellectual algorithms is designed, which enable to provide remote diagnostics of complications in the pump operation, lift leaks, operability of measuring systems and to recommend the optimal operating regime, speed of acceleration, configuration of control station, tap transformer, and other activities. On the example of description of scheme of bringing the well, which is equipped by electrical submersible or sucker rod pump, on to stable production the sequence of execution of intellectual algorithms is presented within the framework of complex approach. The results of testing are given, in particular it is shown that the prediction of the well operating regime by digital twin allows to achieve the target parameters and avoid to making the additional bringing on to stable production after the main process is over or, otherwise, to diminish the time of bringing the well to the stable production. With examples of real wells a new method of detecting the direction of rotation of submersible motor shaft is illustrated. The estimation of technical and economic effects of implementation of the complex approach during bringing the well on to stable production is done. The total annual effect for the Bashneft-Dobycha wells achieves 35 million rubles due to diminishing of the number of pump stops and failures during the bringing on to stable production.

References

1. Zhonin V.V., Valiakhmetov R.I., Enikeev R.M. et al., ANK Bashneft on the way to perfection: bringing wells to production as an element of monitoring the mechanical fund (In Russ.), Inzhenernaya praktika, 2015, no. 9, pp. 9–12.

2. Mal'tsev N.V., Prediction of flow characteristics and submersible equipment performance during ESP startup (In Russ.), Neft', gaz i biznes, 2012, no. 8, pp. 72–75.

3. Gribennikov O.A., Mel'nikov A.A., Monitoring of reservoir characteristics by the data of bringing on the well to stable production (In Russ.), Neftepromyslovoe delo, 2020, no. 4(616), pp. 27–31.

4. Pashali A.A., Kolonskikh A.V., Khalfin R.S. et al., A digital twin of well as a tool of digitalization of bringing the well on to stable production in Bashneft PJSOC (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 3, pp. 80–85, DOI: 10.24887/0028-2448-2021-3-80-84

5. Volkov M.G., The metodology calculation natural gas separation efficiency during well startup phase (In Russ.), Neftegazovoe delo, 2016, V. 14, no. 4, pp. 45–49.

6. Arkhipov D.S., Latypov B.M., Sil'nov D.V. et al., Ways to improve the energy efficiency of electric submersible pump units for oil production using digital twins (In Russ.), Neftegazovoe delo, 2021, V. 19, no. 1, pp. 42–50.

7. Pashali A.A., Khalfin R.S., Sil'nov D.V. et al., Integrated model “Reservoir – Well – Pump” for unsteady fluid flow regimes calculating (In Russ.), Neftegazovoe delo, 2021, V. 19, no. 1, pp. 33–41, DOI: 10.17122/ngdelo-2021-1-33-418.

8. Volkov M.G., Sil'nov D.V., Topol'nikov A.S. et al., Automated system for interpreting technical condition from dynamograms based on machine learning tools (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2021, no. 4, pp. 102–105, DOI: 10.24887/0028-2448-2021-4-102-105

References

1. Certificate no. 2016618641 to a computer program “Avtotekhnolog-virtual'nyy raskhodomer” (Avtotehnolog - virtual flow meter), Authors: Ivanovskiy V.N., A.A. Sabirov, A.V. Degovtsov et al.

2. Shevchenko S.D., Yakimov S.B., Ivanovskiy V.N. et al., Development of the algorithm providing calculation of oil wells flow-rates operated by means of usage of electrical submersible pumps (In Russ.), Oborudovanie i tekhnologii dlya neftegazovogo kompleksa, 2013, no. 6, pp. 90-91.

3.  Ivanovskiy V.N., Sabirov A.A., Gerasimov I.N., Intelligent hardware and software systems protect downhole equipment from salt deposits (In Russ.), Territoriya NEFTEGAZ, 2015, no. 4, pp. 21–25.

4. Ivanovskiy V.N., Sabirov A.A., Donskoy Yu.A., Forecasting as a way of struggle against salt deposits in wells, equipped with electrocentrifugal pumps (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2009, no. 5, pp. 26–29.

5. Ivanovskiy V.N., Sabirov A.A., Donskoy Yu.A., A new conceptual approach to protecting submersible equipment from scale deposits  (In Russ.), Territoriya NEFTEGAZ, 2013, no. 9, pp. 21–26.

6. Ivanovskiy V.N., Sabirov S.A., Donskoy Yu.A., Intellectualization of oil production: new opportunities, developments and trends (In Russ.), Inzhenernaya praktika, 2014, no. 9, pp. 8–11.

7. Israfilov R.T., Experience of Varyeganneftegaz in the protection of underground equipment from corrosion using chemicals. Review of the technical conference of Rosneft OJSC (In Russ.), Inzhenernaya praktika, 2014, no. 2, pp. 14–18.

8. Patent RU 2 652 219 C1. Method of determining flow rate of wells equipped with pumping units, Inventor: Zolotarev A.V.

9. Rzaev Ab.G., Guluev G.A., Abdurakhmanova A.M. et al., Measurement of oil wells flow-rate (In Russ.), Avtomatizatsiya, telemekhanizatsiya i svyaz' v neftyanoy promyshlennosti, 2016, no. 7, pp. 26–29.

10. Yakimov S.B., Ivanovskiy V.N., Sabirov A., New approach to selection of pumping equipment and the mode of its operation in the wells under conditions of sand and proppant sloughing (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 11, pp. 52–55, DOI: 10.24887/0028-2448-2017-11-52-55.

11. Dolov T.R., Kuznetsov I.V., Determination of the influence of operating conditions and standard sizes of ESPs on the degradation of their characteristics (In Russ.), Inzhenernaya praktika, 2019, no. 11–12, pp. 62–66.

12.  Sabirov A.A., Degovtsov A.V., Kuznetsov I.V. et al., Forecasting the operating time to failure, selection of design and optimization of procurement of electric centrifugal pump installations for complicated wells stock (In Russ.), Territoriya NEFTEGAZ, 2019, no. 7–8, pp. 20–27.

13. Borovkov A.I., Burdakov S.F., Klyavin O.I. et al., Komp'yuternyy inzhiniring (Computer Engineering), St. Petersburg, Publ. of  Polytechnic University, 2012, 93 p.

14. National standard of the Russian Federation. Komp'yuternye modeli i modelirovanie. Tsifrovye dvoyniki. Obshchie polozheniya (Computer models and modeling. Digital twins. General provisions), Moscow: Standartinform Publ., 2020.

15. Borovkov A.I., Gamzikova A.A., Kukushkin K.V., Ryabov Yu.A., Tsifrovye dvoyniki v vysokotekhnologichnoy promyshlennosti (Digital twins in the high-tech industry), St. Petersburg: POLITEKh-PRESS Publ., 2019, 62 p.

Tanks for storing, receiving, transfer and measuring oil and petroleum products are high-risk facilities whose system reliability and performance depend primarily on the quality of the equipment used, which is subject to seismic and climatic effects, corrosive external agents, the working environment, as well as mechanical stresses that the equipment experiences during operation and maintenance of the tank. Therefore, the processes aimed at ensuring and increasing the reliability of the used tank equipment are always relevant to the oil and gas industry.

The article is devoted to the processes aimed at increasing the reliability of tank equipment, the most important of which is the assessment of the conformity of the quality of equipment supplied for the construction, repair and reconstruction of vertical steel reservoirs (tanks) operated at hazardous production facilities of the pipeline transportation of Transneft oil and petroleum products. The article discusses the outstanding issues faced by large companies in the oil and gas industry of the Russian Federation related to improving the reliability of tank equipment, and also considers examples of the main technical requirements for compliance with which the quality of tank equipment is assessed. The material presented in the article clearly demonstrates the potential for improving the quality and reliability of tank equipment through modern and efficient approaches used in Transneft oil and petroleum product pipeline transportation system. The article considers four main types of tank equipment as an example: manifold, storm water drainage system for floating tank roof, siphon drain, floating roof seal, which are included in the list of main products used by Transneft system organisations and subject to assessment of compliance with Transneft oil and petrolium products pipeline transportation regulatory technical requirements.

References

1. Efremov A.M., Aralov O.V., Buyanov I.V., Zhizhin D.A., Development of the branch system of accreditation in JSC "Transneft" (in Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products Pipeline Transportation, 2014, no. 4, pp. 90 – 97.

2. URL: https://www.nmdcomp.ru/

3. Gurevich D.F., Raschet  i konstruirovanie truboprovodnoy armatury (Calculation and design of pipeline fittings), Leningrad: Mashinostroenie Publ., 1968, 888 p.

4. Gurevich D.F., Truboprovodnaya armatura: Spravochnoe posobie (Pipeline fittings), Leningrad: Mashinostroenie Publ., 1981, 368 p.

5. Karavaychenko M.G., Babin L.A., Usmanov R.M., Rezervuary s plavayushchimi kryshami (Tanks with floating roofs), Moscow: Nedra Publ., 1992, 236 p.

6. Aralov O.V., Buyanov I.V., Otsenka sootvetstviya produktsii v Rossii i zarubezhom (Conformity assessment of products in Russia and abroad), Proceedings of XII International educational, scientific and practical conference “Truboprovodnyy transport-2017” (Pipeline transport-2017), 2017, pp. 10–12.

7. Aralov O.V., Industry conformity assessment system for equipment and materials used by OJSC Transneft (In Russ.), Nauka i tehnologii truboprovodnogo transporta nefti i nefteproduktov = Science & Technologies: Oil and Oil Products P

Recently, the sphere of application of the 20 kV voltage class in electrical distribution system of various purposes has been expanding extensively. Voltage 20 kV is included in the standard range of rated voltages 10 – 20 – 35 kV. First of all, the transfer of electrical networks traditionally using voltages of 10 (6) and 35 kV to 20 kV networks is considered. Tables and graphs presented in various publications illustrate theoretically substantiated results: with an increase in voltage in overhead transmission line of the same section, it is possible to transmit more power or reduce power (and voltage) losses, or to find the optimal balance of the ratio of transmitted power and power losses. However, from the point of view of the power supply, oil fields as technological objects have their own peculiarities that should be taken into account when their power supply systems are designed. The main purpose here is to ensure a flexible response of power supply systems to technologically determined changes in electrical loads, the optimal location of technological facilities, expansion of the territory at all stages of field development, while maintaining the required level of reliability and quality of power supply to facilities. In the classical oil field power supply system with voltages of 35 and 10 kV, the basic power supply network of the oil field with the necessary power resources is formed at a voltage of 35 kV with the placement of substations in the centers of electrical loads of the oil fields. The 10 kV network can flexibly respond to changes in the location and capacity of individual technological objects. Such a scheme provides the required power supply reliability and flexibility at all stages of development. The transfer of the oil field's power supply system to 20 kV will drastically limit its ability to respond to changing technology requirements, both due to its less flexibility compared to the 10 kV network and due to capacity limitations compared to the 35 kV network. Therefore, with all the active general industrial development of 20 kV networks, the widespread use of this voltage class for power supply of oil fields does not seem promising.

References

1. Ageev V.A., Dushutin K.A., Eremeev E.N., Semenov G.N., Issledovanie rezhimov elektricheskikh setey pri perevode na napryazhenie 20 kV (Study of the modes of electrical networks when switching to a voltage of 20 kV), Collected papers “Energoeffektivnye i resursosberegayushchie tekhnologii i sistemy” (Energy-efficient and resource-saving technologies and systems), Proceedings of International Scientific and Practical Conference, Saransk, 2019, pp. 226–230.

2. Sadokhina M.A., Sadokhin A.I., Gerasimov D.O., Suslov K.V., Preimushchestva i nedostatki elektricheskikh setey 20 kV (Advantages and disadvantages of 20 kV electrical networks), Collected papers “Elektroenergetika glazami molodezhi” (Electric power industry through the eyes of youth), Proceedings of VII International Youth Scientific and Technical Conference, Kazan', 2016, pp. 206–209.

3. URL: https://depjkke.admhmao.ru/upload/iblock/780/elektroenergiya_pp_2_2015.pdf

4. Volod'ko A.A., Lapaev D.G., Bogachkov I.M., Ovchinnikov P.A., 6 kV feed lines for oil and gas condensate fields. Increased throughput (In Russ.), Novosti elektrotekhniki, 2015, no. 1(91), URL : http://www.news.elteh.ru/arh/2015/91/08.php.

5. Bogachkov I.M., Novikova M.V., 20 kV – optimal'noe reshenie dlya elektrosnabzheniya neftegazovykh mestorozhdeniy (20 kV is the optimal solution for power supply of oil and gas fields), Collected papers “Problemy razvitiya gazovoy promyshlennosti” (Gas industry development problems), Proceedings of XX scientific and practical conference of young scientists and specialists, Tyumen': Publ. of Gazprom proektirovanie, 2018, pp. 123–126.

6. Bogachkov I.M., Khamitov R.N., Veliev M.K., The choice of the optimal voltage class of gas field electricity supply system (In Russ.), Elektrotekhnicheskie sistemy i kompleksy, 2020, no. 4(49), pp. 35–41.

The article presents the results of comprehensive experimental studies aimed at investigating the relationship between base metal and welding parameters (chemical composition of welded pipes and welding consumables, welding mode), the structure of received weld metal, its basic mechanical properties (strength, ductility and impact strength), and the parameters of static and cyclic cracking strength, used within the force criterion of fracture mechanics. For this purpose, standard and special metal tests have been carried out as well as a study of metal structure after heat treatment over a wide range of cooling rates. The established correlations were confirmed by testing the ring type welded pipe joints and tanks’ steel structures, welded using the most common Transneft technologies. Based on the results obtained, a model has been developed for refining the operability of welded joints according to the initial data of various levels. In particular, the influence of the cooling rate and main parameters of the welded joint metal structure on the change in its basic mechanical properties has been established. In addition, empirical expressions linking a set of mechanical properties (impact strength, relative elongation and proof/ultimate ratio), combined into a complex performance factor, to the metal cracking strength parameters used within the force criterion of fracture mechanics. In order to obtain the greatest practical outcome from the implementation of the developed model, it is proposed to introduce differentiated reduction factors when carrying out strength and durability calculations in accordance with current normative documentation, depending on the level of available data on the welded joint.

References

1. Idrisov R.Kh., Idrisova K.R., Kormakova D.S., Analysis of accident rate of main pipelines in Russia (In Russ.), Transport i khranenie nefteproduktov i uglevodorodnogo syr'ya, 2019, no. 2, pp. 44–46.

2. Aladinskiy V.V., Mel'nikova A.V., Formation of requirements for the geometry and properties of welded joints of pipes, ensuring the reliability of pipelines (In Russ.), Nauka i tekhnika v gazovoy promyshlennosti, 2009, no. 4 (40), pp. 43–48.

3. Golikov N.I., Ammosov A.P., Prochnost' svarnykh soedineniy rezervuarov i truboprovodov, ekspluatiruyushchikhsya v usloviyakh Severa (Strength of welded joints of tanks and pipelines operating in the North), Yakutsk: Publ. of North-Eastern Federal University, 2012, 232 p.

4. Makarov E.L., Yakushin B.F., Teoriya svarivaemosti staley i splavov (Theory of weldability of steels and alloys), Moscow: Publ. of Bauman University, 2014, 487 p.

5. Savkin A.N., Andronik A.V., Koraddi R., Determination of the coefficients of the crack growth rate equation upon cyclic load (In Russ.), Zavodskaya laboratoriya. Diagnostika materialov, 2016, V. 82, no. 1, pp. 57–63.

6. Mamontov V.A., Kuzhakhmetov T.A., Iksanov R.U., Doan Van Tin', Diagram building of fatigue destruction of ship shaft models (In Russ.), Vestnik AGTU, 2008, no. 5 (46), pp. 44–49.

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9. Zorin A.E., Analysis of structural and thermal processes in welding (to optimize the technology of cutting circular welded joints of pipelines) (In Russ.), Neft', gaz i biznes, 2011, no. 6, pp. 67–70.

10. Zorin A.E., The design of the sample for mechanical testing of pipe metal (In Russ.), Territoriya NEFTEGAZ, 2015, no. 3, pp. 124–128.

11. Zorin A.E., Nauchno-metodicheskoe obespechenie sistemy podderzhaniya rabotosposobnosti dlitel'no ekspluatiruemykh gazoprovodov (Scientific and methodological support of the system for maintaining the operability of long-term operated gas pipelines): thesis of doctor of technical science, Moscow, 2016.

12. Bel'chenko G.I., Gubenko S.I., Osnovy metallografii i plasticheskoy deformatsii stali (Fundamentals of metallography and plastic deformation of steel), Kiev: Vishcha shkola Publ., 1987, 240 p.

13. Bidulya P., Steel foundry practice, 1968, 319 p.

14. Geller Yu., Tool steels, 1978, 659 p.

15. Okerblom N.O., Demyantsevich V.P., Baykova I.P., Proektirovanie tekhnologii izgotovleniya svarnykh konstruktsiy (Designing a technology for manufacturing welded structures), Lenigrad: Sudprom GIZ Publ., 1963, 602 p.

16. Svarka v mashinostroenii (Welding in mechanical engineering): edited by Ol'shanskiy N.A., Moscow: Mashinostroenie Publ., 1978, V. 1, 504 p.