ETM Equipment, Technologies, Materials

EQUIPMENT TECHNOLOGIES MATERIALS ISSN: 2663-8770, E-ISSN: 2733-2055, DOI: 10.36962/ETM AVADANLI Q L A R , T E X N O L O G İ Y A L A R , M A T E R İ A L L A R VOLUME 31 (07) ISSUE 07 2025 CİLD 31 (07) BURAXILIŞ 07 2025 http://emtasoiu.com/index.php/en/archives http://bsj.esif.net/index.php/etm EQUİPMENT TECHNOLOGİES MATERİALS ISSN: 2663-8770, E-ISSN: 2733-2055, DOI: 10.36962/ETM AVADANLI Q L A R , T E X N O L O G İ Y A L A R , M A T E R İ A L L A R VOLUME 31 (07) ISSUE 07 2025 CİLD 31 (07) BURAXILIŞ 07 2025 AZERBAIJAN BAKU 2025 The beautiful thing about learning is nobody can take it away from you—B. B. King CROSSREF FREESIA ISDSJ DISSEMINATION SCORES 2023 – 4.77 QUALITY FACTOR 2023 – 1.3 OAJIF – 1.5 (2023) 2 VOLUME 31 (07) ISSUE 07 2025 Publisher Management Board Member: Ibrahim Habibov. Publisher Technical & Reviewer Team Member: Zuleykha Eyvazova. Publisher Technical & Reviewer Team Member: Zohra Garayeva. Nəşriyyatın İdarə Heyətinin Üzvü: İbrahim Həbibov. 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VOLUME 31 (07) ISSUE 07 2025 3 TABLE OF CONTENTS Sholpan Umbetova, Maarif Yusifov, Asaf Mammadov OPTIMIZATION OF CONTROL IN NON-STATIONARY FLOW CONDITIONS DURING THE RECONSTRUCTION PHASE OF COMPLEX GAS NETWORK ……………………………….……….... 05-18 Shahla Zeynalova, Mirsadi Mustafayev MANUFACTURING TECHNOLOGIES OF ORGANIC SENSORS ……………………………………..... 19-28 Atif Novruzov, Rashad Alirzayev STRATEGIC DIRECTIONS FOR IMPROVING ENTERPRISE COMPETITIVENESS IN THE CONTEXT OF MANUFACTURING INDUSTRY ECONOMIC DEVELOPMENT PRIORITIES ………………………..... 29-38 Abusalam Mukhtarov ASSESSMENT OF GEOTHERMAL ENERGY PROSPECTS IN AZERBAIJAN: A COMPARATIVE ANALYSIS WITH GLOBAL HOT SPRING AND GEOTHERMAL RESOURCE REGIONS …………… 39-45 Rauf Guliyev AN OVERVIEW OF THE AIR DATA INERTIAL REFERENCE SYSTEM (ADIRS) AND ITS INTEGRATION IN MODERN AIRCRAFT AVIONICS ………………………………………………………………………… 46-54 Zаmaddin Allakhverdiyev, Latifa Kazimova CORROSION PROTECTION ASSURANCE IN THE CONSTRUCTION AND OPERATION OF TRUNK PIPELINES ………………………………………………………………………………………………..….… 55-65 Axıra Sultanova DETERMINATION OF OIL POLLUTION OF WATER SURFACE USING AN UNMANNED AERIAL VEHICLE (UAV) .................................................................................................................................... 66-73 Tamilla Khankishiyeva, Javid Mustafayev INVESTIGATION OF THERMAL EFFICIENCY AND OPERATIONAL CHALLENGES IN REFINERY FURNACES …………………………………………………………………………………………………..… 74-82 Yevgeniya Mammadova, Emin Makhmudov METHOD OF ANTIPHASE OPERATION OF PRODUCTION AND INJECTION WELLS ………......… 83-91 Mahammed Shirinov, Vadim Bogopolsky, Azad Bagirov ECONOMIC RISKS IN MODERN SOCIETY ....................................................................................... 92-100 Mehpara Adygezalova RESEARCH UNIVERSAL COMBINED INHIBITOR FOR THE OIL AND GAS INDUSTRY ….…….. 101-109 Abusalam Mukhtarov GEOTHERMAL ENERGY RECOVERY FROM ABANDONED OIL AND GAS WELLS: AN INTEGRATED ASSESSMENT OF POTENTIAL AND APPLICATIONS ………………………………………….……. 110-116 Rugiya Askerova ON THE USE OF POLYETHYLENE PIPES IN LAYING GAS DISTRIBUTION NETWORKS ….….. 117-124 Rita Huseynova, Rufat Hajialiyev MODERN CHALLENGES OF OFFSHORE HYDRAULIC ENGINEERING STRUCTURES AND METHODS FOR THEIR ELIMINATION …………………………………………………………………………..……. 125-134 Gafar Ismayilov, Mahabbat Agasenli, Gulnara Zeynalova ON THE INFLUENCE OF STRUCTURAL CHANGES ON PRESSURE LOSSES IN MULTIPHASE GRAVITATIONAL FLOWS ………………………………………..……………………………………..… 135-141 Rasim Bashirov, Demirel Ramazanov INVESTIGATION OF MECHANISMS FOR MACHINING INTERNAL CYLINDRICAL SURFACES BY PLASTIC DEFORMATION ………………………………………………………...………………………. 142-147 4 VOLUME 31 (07) ISSUE 07 2025 Konul Amirmatova, Gunay Aliyeva THE ROLE OF Ag ALLOYING IN MODIFYING THE STRUCTURE AND CORROSION RESISTANCE OF Mg–Zn ALLOYS ………………………………………………………..…………………………………… 148-154 Nazile Rahimova, Sevil Huseynova PRINCIPLES AND APPLICATION OF CRYPTOGRAPHIC DATA PROTECTION IN IT SERVICES …...……………………………………………………………………………………………… 155-166 Bahar Asgarov, Fereh Veyisli ANALYSIS OF CYBER THREATS TARGETING CRITICAL INFRASTRUCTURE AND ASSESSMENT OF EXISTING APPROACHES TO PROTECTION …………………………………………………...…...… 167-176 Ayten Aliyeva, Leyla Yusifova THE ROLE OF ARTIFICIAL INTELLIGENCE IN DETECTING CYBERATTACKS IN MEDICINE AND EDUCATION ………………………………………………………………………………………………… 177-188 Ali Hikmat Ahmadov, Gulshad Qasimova MATHEMATICAL MODELING OF PACKER SEALS USED IN WELL REPAIR …………...………... 189-195 Mahammad Sofiyev, Rovshana Aliyeva THE ANALYSIS OF OPERATION OF A DIRECT-FLOW GATE VALVE OF A WELL EQUIPMENT …………………………………………………………………………………..…………….. 196-201 Javida Damirova ALCULATION OF THE LOAD ON THE ROD SUSPENSION DURING UNSTEADY OSCILLATORY MOTION OF THE RODS OF A WELL PUMPING INSTALLATION …………………………………… 202-213 Gulbala Aleskerov, Yasin Suleymanli, Rugiya Askerova INFRASTRUCTURE DEVELOPMENT FOR TRANSPORTING HIGH-VISCOSITY OIL ….………... 214-224 Yasin Suleymanli, Rugiya Askerova ASSESSMENT OF ECOLOGICAL IMPACTS IN THE TRANSPORTATION OF HIGH-VISCOSITY OILS AND INTEGRATION OF BIOREMEDIAL STRATEGIES ………………………………………..……... 225-234 VOLUME 31 (07) ISSUE 07 2025 5 OPTIMIZATION OF CONTROL IN NON-STATIONARY FLOW CONDITIONS DURING THE RECONSTRUCTION PHASE OF COMPLEX GAS NETWORK Sholpan Umbetova¹, Maarif Yusifov2, Asaf Mammadov2 1Korkyt Ata Kyzylorda University, Kazakhstan, Kyzylorda, 2Azerbaijan University of Architecture and Construction, Department of Operation and Reconstruction of Buildings and Structures, Baku, Azerbaijan. https://orcid.org/0000-0002-5015-8354 E-mails: 1umbetova[email protected], 2m[email protected], [email protected] ABSTRACT This paper presents a new approach to the mathematical modeling of unsteady flow processes in gas pipelines and the determination of automatic valve closure time. As a result of the modeling, an analytical function describing the time-dependent pressure variation was derived, and a general methodological framework was developed for calculating the closure time by taking into account the leakage location and the attenuation coefficient. Two main criteria for valve actuation were considered: when the rate of pressure decrease exceeds the critical threshold, or when the pressure drops by at least 20% from its initial level. The calculations showed that the rate criterion is practically satisfied immediately, while the decisive factor is the 20% relative drop criterion. Example calculations demonstrated that, for a leakage at a distance of 40 km, the valve closure time is approximately 6.8 minutes. At shorter distances, this time is shorter; at longer distances, it becomes longer, and in some cases the required 20% reduction does not occur within the given time window. In addition, a power-law dependence for the attenuation coefficient as a function of distance was established, and the variation of closure time with distance was visualized. The proposed model has practical significance for detecting leakages in gas pipelines and optimizing automatic valve mechanisms in emergency situations. The results confirm that coordinated valve closure reduces gas loss and increases safety. Keywords: Unsteady gas flow; Pipeline reconstruction; Emergency valve control; Centralized monitoring; Pressure dynamics. Introduction The reconstruction of gas supply systems primarily involves the modernization of existing pipeline infrastructure, enhancement of gas transmission capacity, assurance of high operational reliability, and improvement of equipment efficiency. One of the most effective approaches to reconstruction is the replacement of morally and physically outdated equipment with modern, high-efficiency, and safe systems that comply with current industrial standards. This strategy is 05-18 Publication history Article received: 06.10.2025 Article accepted: 03.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-05 6 VOLUME 31 (07) ISSUE 07 2025 aimed at increasing pipeline productivity and also entails the implementation of new operational components [1, 2, 10]. Among these components, special attention is devoted to the automatic emergency shut-off valves (AESVs) used in main gas pipelines. Their main function is to prevent potentially catastrophic events in the event of sudden pipeline ruptures. The operating principle of such valves is based on monitoring the rate of pressure drop. Specifically, when the pressure decrease exceeds 0.1 MPa per minute, the corresponding control valve automatically triggers the shut-off mechanism. This pressure reduction is calculated as the difference between the initial steady-state pressure and the pressure decrease over time following a complete rupture [14, 15]. Empirical observations have shown that, during severe ruptures, the rate of pressure decrease can reach 0.2–0.5 MPa per minute. Consequently, the development of new operating principles that ensure reliable functioning of AESVs even at lower pressure drop rates is an urgent task, particularly in the reconstruction of complex gas pipeline systems [7, 8]. Although conventional mechanical shut-off valves do not rely on external power sources, they require high maintenance and calibration costs. Modern electronic shut-off valves, on the other hand, are more costeffective, equipped with IoT-based continuous pressure sensors, and provide sufficiently reliable performance. However, since their activation is still based solely on local pressure reduction, delayed or inefficient responses may occur in complex network topologies. Recent studies have emphasized the importance of advanced and adaptive control systems. For example, Zhao et al. [3] developed a multi-objective optimization method for natural gas pipeline route selection, highlighting the significance of real-time operational criteria at the planning stage. Qiao et al. [5] presented a comprehensive review of gas demand forecasting, demonstrating the importance of integrating dynamic prediction and system response in modern pipeline management. Furthermore, research on branched and partially loaded networks [7, 9], as well as the control of non-stationary regimes [13], has confirmed the relevance of advanced modeling techniques for early leak detection and reliable operation under variable demand conditions. A number of researchers have focused on modeling pressure dynamics and gas flow under unsteady conditions, which constitutes a fundamental prerequisite for pipeline system reconstruction and dispatch optimization [6, 8, 12]. In particular, dynamic flow modeling [9, 13], automation of control systems [11], and optimization under varying demand conditions [12] have laid the groundwork for improving gas distribution reliability. The research presented in this paper aims to overcome the limitations of traditional AESV operation principles. The novelty lies in redefining the activation logic of the valves: instead of relying on isolated sensors, it is proposed that the valves located on both sides of the leak point be simultaneously closed based on a centralized pressure impulse signal. This approach enables faster isolation of the damaged section and ensures uninterrupted gas delivery to consumers through parallel pipelines. To support this concept, an analytical framework based on non-stationary gas dynamics has been developed. This framework combines a system of differential equations describing variations in pressure and mass flow with Laplace transform methods and empirical validation. The model allows the computation of closing time, pressure distribution, and calibration parameters to ensure reliable valve operation. VOLUME 31 (07) ISSUE 07 2025 7 Thus, this study provides both theoretical and practical foundations for improving the management of reconstructed gas pipeline systems, minimizing gas losses, and enhancing safety and continuity under emergency conditions. Materials and methods This section presents the theoretical framework, mathematical model, and simulation parameters used to analyze the behavior of complex gas pipeline systems under leakage conditions. Theoretical model and conceptual framework In conventional linear gas pipelines, automatic emergency shut-off valves (AESVs) typically operate independently, triggered solely by the local rate of pressure drop. However, such an approach is not sufficiently effective in complex gas distribution networks consisting of branched and parallel pipelines, particularly under unsteady flow conditions. In these networks, coordinated response strategies are required to prevent excessive gas loss and ensure uninterrupted supply to consumers. The model proposed in this study introduces a new concept that takes into account the dynamic interactions between parallel gas pipelines. As illustrated in Figure 1, the parallel pipeline system is equipped with AESVs and interconnecting lines installed at various strategic locations. As seen in the figure, apart from the interconnections located at the beginning and the end of the pipeline, each intermediate connecting line (or junction) is equipped with two automatic valves - one on the right and one on the left. In case of an emergency, however, the operation of only one valve on a given side is not sufficient. To minimize gas losses, both valves located on either side of the leakage point must be closed simultaneously. Therefore, the traditional approach - where each valve operates independently based on its own local pressure drop - is inadequate. The pressure sensors of the AESVs should be linked in a centralized manner, so that when a leak occurs, both valves on either side of the damaged segment are activated simultaneously. Figure 1: Schematic diagram of the efficient arrangement of automatic emergency shut-off valves in complex gas pipeline systems. 1 – pipeline of the parallel gas main; 2 – interconnecting line of the parallel pipelines; 3 – valves that trigger the operation of the automatic shut-off system; 4 – automatic emergency shut-off valves (AESV); L – total length of the gas pipeline; ℓ – distance from the pipeline inlet to the valve located upstream of the accident; ℓ₁ – distance from the pipeline inlet to the leakage 1 1 2 2 2 3 4 5 3 4 5 3 4 5 3 4 5 3 4 3 4 3 4 5 3 4 5 5 4 5 4 5 4 L 1 Gut P1 P1 P2 P2 8 VOLUME 31 (07) ISSUE 07 2025 point; Gut – mass of gas leaking from the ruptured section at point (x = ℓ₁); P₁ and P₂ – gas pressures at the inlet and outlet of the pipeline, respectively, under steady-state flow conditions. Based on Figure 1, the effective operation of AESVs requires the synchronized activation of the right-hand valve of one interconnecting line and the left-hand valve of the subsequent line, starting from the inlet of the pipeline. This synchronization is essential to ensure that both sides of the damaged segment are simultaneously closed, maintaining uninterrupted gas supply to consumers. If a leak occurs at a certain point ℓ₁, the control logic ensures that the two valves located to the left and right of this point close simultaneously, thereby isolating the damaged segment. Unlike traditional approaches, this control mechanism does not rely solely on the local pressure drop detected by each valve. Instead, it is governed by an impulse signal from centralized sensors placed near the pipeline inlet. Consequently, the system detects the pressure impulse generated by the leakage and triggers the simultaneous closure of both valves. The model is based on the following assumptions: - The parallel pipelines have identical diameters and operate in a quasi-steady-state regime prior to the occurrence of the accident. - The initial parameters - mass flow rate G0 and inlet pressure P1 - are known. - The temporal variations in pressure and mass flow are described by exponential decay functions. - The pressure dynamics are modeled using the linearized form of I.A.Cherny’s equations for unsteady gas flow. To support the reconstruction strategy, the model incorporates the synchronized operation of the AESV pairs located at each interconnecting line. Thus, the valves situated to the left and right of the interconnection closest to the leakage point are closed simultaneously, ensuring safe isolation of the damaged segment. This conceptual framework also introduces the idea of time-constrained valve activation, where the valve closure duration is determined by both the rate of pressure decrease and the maximum delay time t1 beyond which the accident may become uncontrollable. Analytical expressions for this delay are derived based on the Laplace transform of the pressure functions within the pipeline. Hence, the proposed model resolves the inconsistencies between traditional AESV operation principles and the requirements of modern gas distribution systems, enabling the implementation of intelligent and rapid control strategies. Mathematical model and boundary conditions In complex gas pipeline systems, the dynamic behavior of gas flow during emergency situations is governed by non-stationary processes. These processes are modeled using a system of linear differential equations, while the physical phenomena - such as leakage and valve activation -are represented through appropriate boundary and initial conditions. Governing equations For each segment of the pipeline, the pressure P(x,t) and mass flow rate G(x,t) are described by the linearized form of the unsteady gas flow equations: VOLUME 31 (07) ISSUE 07 2025 15 The variation of the attenuation coefficient with distance was interpolated based on experimental points and the dependence β(ℓ)=kℓm was established (m≈−0.36m, k≈0.16). This dependence allows us to predict the closing time of the valves in advance. In the exemplary calculations, the closing time for a distance of ℓ=40 km is determined as t1≈6.8 min. At small distances, this time is shorter, at large distances it is longer, and in some cases the 20% drop does not occur in the given time window. The graphs and calculation tables prepared based on the proposed model are of great importance in practical applications (SCADA systems, placement and calibration of automatic valves for emergency situations). Using the algorithm and calculation methods developed based on the results of the analysis, we will achieve effective solutions for the reconstruction of complex main gas pipelines, taking into account the non-stationary regime. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES 1. I.G. Aliyev, (2025). Technological Foundations of Management Decision-Making in the Reconstruction of Complex Gas Pipeline System. Cornell University, USA. arXiv org. DOI: https://doi.org/10.48550/arXiv.2504.11488 2. Aliyev I.G., Takhmazov F.I., Yusifov M.Z., Mammadova N.A. (2024). Technological foundations of multiline gas pipeline reconstruction. International Journal on Technical and Physical Problems of Engineering ( IJTPE), Vol.16, 2,June 2024, Pages 122-127, 17IJTPE-Issue59-Vol16-No2-Jun2024-pp122-127.pdf 3. Tong ZHAO , Xu WANG, Sheng-zhu ZHANG, Ying-quan DUO, Jin-huai XU, Sai-Tao. (2024). 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Gafarov, S.M., & Aslanov, R.M. (2022). Optimization of gas distribution under unsteady demand conditions. Journal of Energy and Power Engineering, 16(2), 83–91. https://doi.org/10.17265/1934-8975/2022.02.005. 13. Rakhmanov, T.I. (2018). Control of unsteady regimes in pipeline networks. Chemical and Petroleum Engineering, 54(5-6), 325–331. https://doi.org/10.1007/s10556-018-0421-z 14. Zenfira Huseynli, Calal Babazade, Gulnar Hamidova, Niyaz Zeynalov.(2023).Study of the cause of failure of main elements of the gate valve and effective solution ways. Equipment Technologies and Materials, Volume 14.1, ISSUE 02, pp 31-38. ISSN: 2663-8770, EISSN: 2733-2055. 15. Sabir Babaev, Ibrahim Habibov, Zohra Abiyeva. (2021) Evolution of the quality of highpressure valves during the period of their intensive development. Equipment Technologies and Materials, Volume 05, ISSUE 01, pp 4-10. ISSN: 2663-8770, E-ISSN: 2733-2055, MÜRƏKKƏB QAZ ŞƏBƏKƏLƏRİNİN REKONSTRUKSİYASI MƏRHƏLƏSİNDƏ QEYRİ-STASİONAR AXIN ŞƏRAİTİNDƏ İDARƏ OLUNMASININ OPTIMALLAŞDIRILMASI VOLUME 31 (07) ISSUE 07 2025 17 Sholpan Umbetova1, Maarif Yusifov2, Asəf Məmmədov2 1Qazaxıstan, Kyzylorda, Korkut Ata adına KızılOrda Universiteti, 2Bakı, Azərbaycan Memarlıq və İnşaat Universiteti, “Bina və qurğuların istismarı və rekonstruksiyası” kafedrası. https://orcid.org/0000-0002-5015-8354, E-mail: 1umbetova-3[email protected], 2maarif[email protected], [email protected] XÜLASƏ Bu məqalədə qaz kəmərlərində qeyri-stasionar axın proseslərinin riyazi modelləşdirilməsi və klapanların avtomatik bağlanma vaxtının təyini üzrə yeni yanaşma təqdim olunur. Modelləşdirmə nəticəsində təzyiqin zamana görə dəyişməsini əks etdirən analitik funksiya əldə edilmiş, sızma nöqtəsinin məsafəsi və zəiflətmə əmsalı nəzərə alınaraq bağlanma vaxtının hesablanması üçün ümumi metodoloji çərçivə formalaşdırılmışdır. Klapanların işə düşməsi üçün iki əsas meyar nəzərdən keçirilmişdir: təzyiqin azalmasının sürəti kritik həddi aşdıqda və ya təzyiqin başlanğıc səviyyəsindən azı 20% azalması baş verdikdə. Hesablamalar göstərmişdir ki, sürət meyarı demək olar ki, dərhal təmin olunur, lakin əsas həlledici amil 20%-lik nisbi düşüm meyarıdır. Nümunəvi hesablamalar göstərmişdir ki, 40 km məsafədə sızma üçün bağlanma vaxtı təxminən 6,8 dəqiqə təşkil edir. Daha yaxın məsafələrdə bu vaxt daha qısa, uzaq məsafələrdə isə daha uzun olur və bəzi hallarda verilmiş zaman pəncərəsində tələb olunan 20%-lik azalma baş vermir. Əlavə olaraq, məsafədən asılı zəiflətmə əmsalı üçün güc tipli asılılıq qurulmuş və məsafə üzrə bağlanma vaxtının dəyişməsi qrafikləşdirilmişdir. Təklif olunan model qaz kəmərlərində sızmaların aşkarlanması və qəza hallarında avtomatik bağlanma mexanizmlərinin optimallaşdırılması baxımından praktik əhəmiyyət daşıyır. Nəticələr təsdiq edir ki, klapanların koordinasiyalı bağlanması qaz itkisini azaldır və eləcə də, təhlükəsizliyi artırır. Açar sözlər: Qeyri-stasionar qaz axını; Qaz kəmərinin rekonstruksiyası; Qəza klapan nəzarəti; Mərkəzləşdirilmiş monitorinq; Təzyiq dinamikası ОПТИМИЗАЦИЯ УПРАВЛЕНИЯ В УСЛОВИЯХ НЕСТАЦИОНАРНОГО ПОТОКА НА ЭТАПЕ РЕКОНСТРУКЦИИ СЛОЖНЫХ ГАЗОВЫХ СЕТЕЙ Чолпан Умбетова¹, Маариф Юсифов2, Асеф Мамедов2 ¹Кызылординский государственный университет имени Коркыт Ата, Кызылорда, Казаксктан, 2Азербайджанский университет архитектуры и строительства, кафедра эксплуатации и реконструкции зданий и сооружений, Баку, Азербайджан. https://orcid.org/0000-0002-5015-8354 Email: [email protected], maarif.yusifo[email protected].az, [email protected] РЕЗЮМЕ В данной статье представлен новый подход к математическому моделированию нестационарных процессов течения в газопроводах и определению времени автоматического закрытия клапанов. В результате моделирования получена аналитическая функция, описывающая изменение давления во времени, и разработана общая методологическая основа для расчета времени закрытия с учетом расстояния до места утечки и коэффициента затухания. Рассмотрены два основных критерия срабатывания клапанов: когда скорость снижения давления превышает критический порог, или когда давление уменьшается не менее чем на 20% от исходного уровня. Расчеты показали, что критерий скорости выполняется практически мгновенно, в то время как решающим 18 VOLUME 31 (07) ISSUE 07 2025 фактором является критерий 20%-ного относительного снижения. Примерные вычисления показали, что при утечке на расстоянии 40 км время закрытия клапана составляет примерно 6,8 минуты. На меньших расстояниях это время короче, на больших -дольше, и в некоторых случаях требуемое 20%-ное снижение не достигается в пределах заданного временного окна. Кроме того, установлена степенная зависимость коэффициента затухания от расстояния и построены графики зависимости времени закрытия от расстояния. Предложенная модель имеет практическое значение для выявления утечек в газопроводах и оптимизации работы автоматических клапанов в аварийных ситуациях. Полученные результаты подтверждают, что координированное закрытие клапанов снижает потери газа и повышает безопасность. Ключевые слова: Нестационарный газовый поток; Реконструкция газопроводов; Аварийное управление клапанами; Централизованный мониторинг; Динамика давления. VOLUME 31 (07) ISSUE 07 2025 19 MANUFACTURING TECHNOLOGIES OF ORGANIC SENSORS Shahla Zeynalova1, Mirsadi Mustafayev2 1Docent, National Aviation Academy. E-mail: [email protected] 2Phd student, National Aviation Academy. E-mail: [email protected] ABSTRACT The development of organic sensors has accelerated rapidly owing to their mechanical flexibility, biocompatibility, and cost-effective fabrication potential. However, their large-scale implementation critically depends on mastering reliable manufacturing processes capable of producing uniform and high-performance layers. This study systematically analyzes the principal fabrication technologies applied to organic sensor production—particularly flexography, gravure, screen, and inkjet printing, as well as spin coating. Each method is examined in terms of its process sequence, precision, and adaptability to flexible substrates. The comparison shows that contact printing techniques ensure high throughput and multilayer capability, whereas non-contact digital printing enables selective, mask-less deposition with minimal material waste. Coating approaches further refine film uniformity and structural continuity, improving the stability and integrity of functional layers. Integrating these additive and solution-based routes establishes a scalable framework for low-cost and environmentally compatible device fabrication. The findings emphasize that roll-to-roll and inkjet processes connect laboratory experimentation with industrial production, defining the technological basis for next-generation flexible, lightweight, and sustainable sensor systems that combine functional reliability with manufacturable simplicity. Keywords: organic sensor, printing technique, substrate, flexible electronics, layer, fabrication, process. Introduction Organic sensors have emerged as a promising class of devices that leverage carbon-based materials to detect environmental, chemical, or biological signals. They offer advantages like mechanical flexibility, low-cost fabrication, and biocompatibility, enabling applications from wearable health monitors to environmental detectors. However, realizing these benefits at scale depends critically on the development of suitable manufacturing technologies. Unlike conventional silicon sensor fabrication, which relies on rigid substrates and subtractive lithography, organic sensors can be produced through additive manufacturing techniques that deposit functional materials directly onto flexible platforms [3]. This approach avoids complex masking and etching steps, resulting in a cleaner process with less material waste. A variety of printed electronics methods have been adapted for organic sensor fabrication. The two main categories are contact printing and non-contact printing. In contact printing methods 19-28 Publication history Article received: 06.10.2025 Article accepted: 03.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-19 20 VOLUME 31 (07) ISSUE 07 2025 (such as gravure, screen, and flexography), patterned rolls or stencils transfer conductive or sensing ink onto the substrate through direct physical contact [1]. These techniques are compatible with high-throughput roll-to-roll production, allowing continuous printing on flexible substrates. Non-contact printing methods like inkjet printing eject droplets of ink in precise patterns without touching the substrate [2]. Inkjet is especially useful for rapid prototyping and complex or multi-material designs, since it is a digital, mask-less process. Alongside printing, solution-based coating techniques (e.g. spin coating, slot-die coating, blade coating) are employed to deposit uniform thin films of organic semiconductors or sensing layers. Additionally, laser patterning and other advanced structuring methods can define fine features or remove material to create sensor patterns without physical masks. Together, these manufacturing technologies provide a toolbox for fabricating the various layers and components of an organic sensor on plastic, paper, or textile substrates. The adoption of printing and coating techniques in sensor manufacturing has opened the path toward scalable production of flexible sensor systems. Roll-to-roll printing on large-area substrates enables high-throughput fabrication of cost-effective sensors under ambient conditions [4]. This means that hundreds or thousands of organic sensor devices can be printed in a single batch, dramatically lowering unit costs and supporting disposable or ubiquitous sensor applications. The printed sensors retain performance on curved or stretchable surfaces, which is difficult to achieve with traditional rigid electronics. Indeed, a wide range of physical and chemical sensor types – including strain gauges, optical sensors, pressure sensors, and electrochemical gas sensors – have already been realized using these printable technologies. Such demonstrations underscore the versatility of modern manufacturing techniques in the organic electronics domain. In the following, we focus on the key manufacturing technologies of organic sensors and their principles, capabilities, and current developments. Printing techniques like flexography, gravure, screen, and inkjet printing are reviewed with regard to how they pattern sensor components and the quality of devices they produce. We also examine coating processes (spin coating, slot-die, etc.) for forming uniform organic layers, and laser patterning methods for fine-resolution structuring. By aligning with the state-of-the-art practices in printed and flexible electronics, this overview highlights how each fabrication approach contributes to the overall goal of producing reliable, high-performance organic sensors. The main objective is to outline these manufacturing methods and discuss their advantages, limitations, and roles in advancing organic sensor technology, thereby setting the stage for detailed exploration in subsequent sections. Research purpose To examine and systematize contemporary manufacturing technologies applied in organic sensor production, uncovering how fabrication parameters shape structural precision, functional efficiency, and reliability, and to establish a scientifically grounded framework for developing innovative, scalable, and high-fidelity manufacturing approaches that redefine future directions in organic sensor engineering. Flexography. Flexography is a rotary printing technique in which quick-drying inks are transferred onto a variety of substrates using flexible plates made of rubber or other elastomeric materials [7]. The inks employed in this process typically dry through rapid evaporation, enabling efficient and continuous printing across diverse surfaces [1]. Figure 1 illustrates principle of VOLUME 31 (07) ISSUE 07 2025 21 flexography. The inking system comprises a fluid reservoir coupled with an anilox roller, while the printing section consists of a plate cylinder and an impression cylinder. Initially, the printing fluid is formulated, and its viscosity is precisely adjusted during the conditioning stage (0). The fluid, held within a reservoir, is then applied to the rotating anilox roller in the fluid acquisition phase (1). After removal of excess fluid, a controlled quantity remains within the roller’s engraved cells, representing the predosing step (2). Subsequently, the fluid is transferred from the anilox roller to the printing plate—mounted on the plate cylinder and containing the image design—during the dosing stage (3). As is characteristic of all relief printing processes, the image areas are elevated relative to the nonimage areas. The ink is then transferred (4) from these raised regions onto the substrate, which is pressed against the plate by the impression cylinder. This sequence involves two distinct inksplitting actions. Finally, the process concludes with the relaxation (5) and drying (6) stages, ensuring stabilization and fixation of the printed layer. Figure 1: Principle of flexography. Characteristics of print equipment. The anilox roller consists of a steel core coated with a ceramic (Fig. 2 right) or metallic surface containing precisely engraved microcells. It represents a critical component of the inking unit, as it ensures the delivery of a well-defined and uniform quantity of ink to the printing plate. In ceramic anilox rollers, the cells responsible for fluid uptake and transfer are produced through laser gravure technology. Compared with chrome-plated cylinders fabricated mainly by mechanical engraving, ceramic cylinders exhibit superior durability, wear resistance, and operational stability, resulting in an extended service lifetime and improved printing consistency. The gravure angle defines the orientation of the engraved cells on the surface of the anilox roller relative to its rotational axis and typically ranges between 30° and 90° (Fig. 2 left). 22 VOLUME 31 (07) ISSUE 07 2025 Figure 2: Ceramic rollers(right) and hexagonally patterned anilox roller illustrating screen frequency and engraving angle. Key operational parameters of the anilox roller include the screen frequency (measured in lines per centimeter) and the pickup volume (expressed in cubic centimeters per square meter). The pickup volume represents the total volume of all cells within a specified surface area; however, it is important to note that only a portion of this theoretical volume is effectively transferred during the printing process. During the transfer stage, the substrate is gently pressed against the printing plate to ensure proper contact. The resulting printing pressure critically influences print quality and is adjusted as follows: the impression cylinder and plate cylinder are first moved together until they lightly touch—a condition known as kiss printing, where the flexible plate remains undeformed. The distance between the cylinders is then slightly reduced to establish an optimal contact area, or nip, through controlled deformation of the plate, a phase referred to as engagement (see Fig. 3). This low-pressure configuration is particularly suitable for multilayer printing. During operation, the printing plate rolls over the substrate in a continuous rotary motion, enabling the adhesion of the ink film. The process concludes with the relaxation and drying stages, which stabilize and fix the printed image on the substrate. Figure 3: In flexography, engagement is the compression between cylinders, and the nip is the contact point where ink transfers to the substrate. VOLUME 31 (07) ISSUE 07 2025 23 Figure 4: Scheme of rotogravure process. Gravure printing. Gravure printing is a cost-effective, high-resolution technique compatible with a wide range of functional inks, making it well-suited for the patterned deposition of organic semiconducting and dielectric layers. Owing to its excellent control over film thickness and uniformity, this method is increasingly employed in the fabrication of flexible and highperformance organic sensors. Gravure printing, also referred to as rotogravure, is a high-speed and large-scale intaglio printing technique in which the image is precisely engraved onto a metal cylinder [5]. During the printing process, the inked cylinder transfers the engraved pattern onto the substrate—commonly polymeric or elastic materials such as PET, PEN, or PDMS—enabling continuous, high-quality fabrication suitable for flexible and large-area applications. Typical rotogravure presses (as illustrated in Fig. 4) are composed of an ink reservoir, a gravure cylinder containing engraved cells that form the printing pattern, and an impression cylinder. Unlike letterpress techniques, gravure printing employs recessed image areas incised into the cylinder surface, where ink is retained and subsequently transferred to the substrate under controlled pressure, enabling uniform and high-fidelity reproduction. During gravure printing, the conditioned functional fluid (0) is usually stored in an ink pan, where the gravure cylinder is partially immersed. As the cylinder rotates, its engraved cells are filled with the fluid—this stage is known as fluid acquisition (1). Once the filled cells leave the reservoir, the cylinder surface becomes covered with a thin, uniform liquid layer, representing the predosing stage (2). Subsequently, a doctor blade removes excess fluid from the non-image areas, leaving uniformly filled cells that contain the precise volume required for transfer—this is the dosing step (3). The metered fluid is then transferred (4) onto the substrate through the pressure exerted between the gravure and impression cylinders, involving a single ink-splitting event. As in all printing processes, the transferred layer then undergoes relaxation (5) and drying (6), forming a stable and uniform coating. In the context of organic sensor fabrication, this controlled sequence ensures accurate layer definition, film uniformity, and compatibility with polymeric or elastic substrates used in flexible electronic devices. Process Description. İn a typical rotogravure press, the ink pan is positioned beneath the gravure cylinder, allowing the cylinder surface to be coated as it rotates through the functional fluid. In laboratory-scale systems, however, the ink is often applied manually using a syringe or pipette. In such setups, the gravure cylinder is not continuously immersed, which can cause solvent evaporation and ink drying on the surface—an effect that alters printing quality. To mitigate this, solvent traps are employed, and the time intervals between coating steps (latency times) are kept minimal. After passing beneath the doctor blade, a precisely metered volume of ink remains within the engraved cells and is subsequently transferred onto the substrate. The efficiency of cell emptying during transfer is primarily determined by two factors: the cell geometry—defined by the engraving depth and screen angle—and the process parameters, such as printing pressure and cylinder velocity. While higher pressures promote more complete ink transfer, this setting is suitable mainly for rough paper in graphic printing. In contrast, for printed and organic electronics applications, the pressure must be minimized—ideally approaching zero—to prevent mechanical deformation or damage to the polymeric or elastic substrate. 24 VOLUME 31 (07) ISSUE 07 2025 İnkjet printing. İnkjet printers differ fundamentally from traditional printing presses in both structure and operation. Their key distinctions are the contact-free ink transfer—classifying them as non-impact printing (NIP) systems—and the absence of a physical printing plate. The main component, called the print head, contains precision nozzles and electronic circuits responsible for ejecting ink droplets (Fig. 5). İn industrial setups, the print head is typically connected to an external ink tank, while smaller laboratory or office printers use sealed cartridges mounted directly onto the print head. Figure 5: Principle of a DOD piezo inkjet. Two principal mechanisms govern droplet formation in inkjet technology: drop-on-demand (DOD) and continuous inkjet. In the DOD approach, droplets are ejected only when required, ensuring precise material deposition. By contrast, the continuous method generates a steady stream of droplets, diverting the excess ones before they reach the substrate. Both concepts employ various actuation mechanisms—most commonly piezoelectric or thermal drivers—to induce fluid excitation and control the droplet ejection process. İn a DOD piezo inkjet print head, several subprocesses occur in sequence. First, the ink is conditioned (0)—homogenized and adjusted for viscosity—then acquired (1) by the print head from the cartridge. Next, a piezo element deforms to generate pressure variations that propel the ink. During predosing (2), a precise volume of ink is drawn toward the nozzle, followed by dosing (3), where pressure waves drive it through the channel to the orifice, initiating droplet formation. Once detached, the droplet transfers (4) to the substrate, where it undergoes relaxation (5), then drying and solidification (6), forming the printed feature. Process description. İnkjet printing begins with fluid conditioning, where the ink is remixed and de-gassed to prevent nozzle clogging from particle agglomerates or air bubbles. After loading the cartridge and connecting it to the print head, the hardware is ready, while the software is programmed with the layout, actuator signals, and cleaning cycles. İn drop-on-demand (DOD) systems, droplets are ejected by creating pressure inside the ink chamber—either by heating and vaporizing the fluid (thermal DOD) or by piezoelectric deformation [6]. The latter uses a tailored waveform of voltage pulses controlling droplet formation and is favored for functional materials, as it avoids thermal damage. VOLUME 31 (07) ISSUE 07 2025 31 to the production process and fosters a positive image of both the product and the enterprise as a whole. Scientists believe that the introduction of digital technologies into product lifecycle management processes is one of the key strategic benchmarks for developing competitiveness in the context of the challenges facing Russian industry. Digital product lifecycle management (DPLM) is becoming a comprehensive concept that replaces the linear processes of traditional lifecycle management with cyclical ones, integrating data from all stages, from design to operation. The key characteristics of DPLM are flexibility (adaptation to real-time market changes), scalability (rapid expansion or contraction of production), intelligence (use of analytics and AI to anticipate needs), and connectivity (data synchronization between devices, users, and partners) [Gerber et al., 2022]. In implementing this concept, a key role is given to "living" devices, which optimize operational processes and ensure hyper-personalization of the consumer experience. Currently, the connection between digitalization and enterprise performance is manifested not only in the additional benefits of its implementation but also in the losses from ignoring digital technologies. In other words, digital transformation of the product lifecycle is not a choice, but a necessity for the survival of enterprises in the context of "industrial consumerism" and growing demands for personalization. It is also important that the close integration of isolated departments (R&D, marketing, production) is even more necessary than decades ago. Organizational changes involve not only retraining employees but also engaging new stakeholders (consumers, partners). K.S. Mayorova and E.S. Balashova note that digitalization requires a transition from isolated projects to integration into cross-industry "smart" ecosystems that unite enterprises, suppliers, customers, partners, and other stakeholders. Such ecosystems accelerate innovation, increase flexibility in responding to market changes, provide access to shared resources, enable enterprises to create personalized services, increase recurring revenue, and remain competitive in the digital economy [Mayorova, Balashova, 2021]. The key strategic benchmarks for developing the competitiveness of industrial enterprises outlined in the analyzed sources are summarized in Table 1. The researchers identify structural imbalances, the high cost of technology, and the lack of a methodology for managing breakthrough development as the main challenges to increasing the competitiveness of industrial enterprises. . In summary, the authors rightly highlight digital transformation (DPLM, platforms, ecosystems) as a key driver of competitiveness. However, the hyper-focus on technology may obscure systemic issues such as the digital divide between large and small businesses (the implementation of AI, "living" devices, and smart ecosystems requires significant investment, which is unaffordable for many Russian companies, especially in regions with high asset depreciation); digitalization imbalances (the service sector's dominance in technology demand indicates industry's weak adaptation to new realities); and the human factor (the transition to cyclical DPLM processes requires not only employee retraining but also a change in corporate culture, which inevitably leads to employee resistance). Considering the controversial aspects noted, we believe that enhancing the competitiveness of industry requires a synergistic approach combining technological, institutional, and social transformations: 32 VOLUME 31 (07) ISSUE 07 2025 1. Digitalization must be implemented in a realistic manner: priority should be given to the modernization of fixed assets and the development of digital platforms for SMEs with state support. 2. Changes driven by the focus on ESG and Industry 5.0 should be evolutionary, not revolutionary. EICSG implementation should occur in stages through pilot projects in highly profitable industries (petrochemicals, metallurgy), where environmental and social investments will have a faster return on investment. ESG criteria could be integrated into public procurement and export standards. 3. Import substitution should be based on global integration. For example, it would be advisable to create clusters not as closed systems, but as nodes in international value chains (as in the case of cooperation with the EAEU in IT and pharmaceuticals). Stimulating foreign direct investment in R&D through special economic zones could also be considered Table 1. Summary of strategic guidelines for developing the competitiveness of industrial enterprises. A benchmark for the growth of enterprise competitiveness Key tasks and challenges for developing competitiveness Recommendations for achieving competitiveness growth objectives 1 2 4 Digitalization and DPLM Replacing linear processes with cyclical ones (DPLM); Flexibility, scalability, intelligence (AI), connectivity; The need to integrate departments and stakeholders. - transition to cross-industry smart ecosystems; - implementation of digital platforms for business process integration. Industry 5.0 and ESG - Synergy between Industry 5.0 (humancentricity, sustainability) and ESG; - Challenges: infrastructure, regulatory barriers, R&D costs. expansion of ESG to EICSG; focus on a "green" agenda for competitiveness in global markets. Modernization of fixed assets - high wear and tear (over 50% in the mining industry); - low renewal and retirement rates; - uneven distribution across regions. - modernization of assets, especially in the mining sector; - an adaptive strategy to reduce depreciation. Import substitution - Dependence on imports (49.2% – machinery, 18.3% – chemical products); - Successful examples of localization. - creation of clusters; - reduction of the key rate to 4%, subsidies for digitalization. Rational proposals for increasing enterprise competitiveness based on other tools also present certain challenges. For example, the proposal to synthesize the EICSG approach appears innovative, but its implementation in the Russian industrial context raises doubts due to infrastructural limitations, including depreciation of fixed assets and low renewal rates, making the introduction of "sustainable" technologies costly and time-consuming. The identified systemic problems and limitations of current approaches to improving the competitiveness of industrial enterprises are reflected in Table 2. In other words, a competitiveness enhancement strategy must be adaptive and take into account both global trends (digitalization, ESG) and the specifics of Russian industry (asset depreciation, regional disparities). The key challenge is overcoming the "partial solutions trap," whereby VOLUME 31 (07) ISSUE 07 2025 33 isolated measures (digitalization of marketing, preferential loans) are not supported by systemic changes (infrastructure, education, institutions). Without this, even technologically advanced companies will remain islands in an ocean of outdated practices (Table 3). Table 2. Systemic problems and limitations of current approaches to improving competitiveness. Problem Characteristic Examples / Consequences Digital divide Uneven technology adoption between large and small businesses due to high costs. Small businesses in regions with depreciating assets cannot implement AI, “living” devices, and smart ecosystems. Digitalization imbalance The service sector dominates demand for digital technologies, while manufacturing lags behind.. Decreased adaptation of industry to new market realities. Human factor Resistance to corporate culture change and staff retraining during the transition to DPLM. Slowing down digital transformation processes. Implementation of the EICSG approach Infrastructure constraints (asset depreciation) and regulatory barriers (lack of ESG standards). High cost and long lead times for implementing sustainable technologies. Problems of import substitution Localization does not guarantee quality, and government subsidies create a “government procurement market,” reducing competition.. Risk of a decrease in innovation activity and product quality. Table 3. Author's proposals for a synergistic approach to increasing the competitiveness of industrial enterprises. Direction Content Novelty of approach Digitalization in line with realities Priority of modernization of funds. Focus on adapting technologies to infrastructure constraints rather than blindly implementing them. Evolutionary ESG implementation A phased transition through pilot projects in highly profitable industries (petrochemicals, metallurgy), integrating ESG criteria into public procurement. Abandonment of revolutionary changes in favor of gradual transformation taking into account economic feasibility. Global integration Creating clusters as nodes in international chains. Import substitution not as isolation, but as integration into global value chains. Synergy is achieved by avoiding a sole focus on technological change, which must be accompanied by institutional change. The following can be highlighted as prospects for increasing competitiveness and factors determining the formation of sustainable competitive advantages for key sectors: 1. The oil and gas sector, with its leading positions in production and developed infrastructure, is dependent on raw material prices, sanctions, and environmental risks. Diversification through LNG production and the implementation of carbon capture technologies is an area for strengthening competitiveness. 34 VOLUME 31 (07) ISSUE 07 2025 Sustainable competitiveness Synergistic approach Society Institutes Technologies 2. The metallurgy and chemical industries, while highly competitive in the global market, face risks from high energy costs and stricter environmental regulations in the EU. Here, competitiveness growth is also associated with the reduction of key risks. 3. Mechanical engineering and the military-industrial complex have a high level of innovative development thanks to government contracts (drones, electronics). However, civil engineering lags in digitalization and the quality of its component base, which are becoming key areas for improvement.. A balance is needed between digitalization and addressing systemic issues (asset depreciation, regional disparities). Furthermore, competitiveness enhancement strategies must be adaptive, emphasizing the evolutionary, rather than revolutionary, implementation of strategic guidelines facing industry. We also note the priority of preserving and enhancing human capital in implementing transformations. A general framework for achieving industrial enterprise competitiveness is presented in Figure 1. Figure 1: Elements of a synergistic approach to achieving industrial enterprise competitiveness. The general strategic directions for increasing the competitiveness of industrial enterprises are determined by the priorities identified above. These include the following: 1. Digital transformation through the implementation of IoT, big data, AI, robotics, and digital twins for process automation. This approach aligns with national priorities, providing access to government funding. The practical application of this competitiveness enhancement tool reduces costs, improves planning accuracy, and increases the speed of response to market changes. 2. Development of R&D and innovative products through increased investment in R&D and the creation of high-added-value products. This approach is also supported by state programs, stimulating the development of critical technologies, enabling import substitution, reducing dependence on sanctions, and building a competitive advantage through product uniqueness. 3. Greening production through the implementation of ESG standards and the transition to green technologies and renewable energy sources. This approach aligns with global trends and export market requirements, provides access to incentives (tax holidays for "green" projects), and promotes profitability. 4. Optimization of logistics and localization of supply chains through the creation of supplier clusters and the development of domestic raw materials and components. Sanctions make localization critically important, which helps build resilience to disruptions in global supply chains. VOLUME 31 (07) ISSUE 07 2025 35 5. Investments in human capital to train personnel for high-tech work and retrain employees. Advanced training provides a competitive advantage. The introduction of digital skills contributes to a significant increase in labor productivity. 6. Export expansion and market diversification, in particular access to markets in Asia, the Middle East, and Africa through participation in government export support programs. Implementing this approach to increasing competitiveness offers the potential for compensation of up to 80% of certification and other costs, reducing dependence on traditional markets. 7. Cooperation with scientific and industry clusters, which provides access to grants for joint projects and innovations (for example, KAMAZ's cooperation with KNITU-KAI led to the creation of an electric truck). 8. Strengthening the brand and building loyalty. The prospects for this area of competitive growth are linked to leveraging the post-sanctions trend toward "patriotic consumers" and creating an emotional connection through storytelling (brand history, support for local communities). For example, the shoe brand Tervolina launched the "Made for Our Own" campaign, increasing brand awareness by 40%. 9. Integration into ecosystems and collaborations. For example, partnerships with IT companies (for example, the introduction of smart features into technology through an alliance with Yandex or Sber) and collaborations with designers and bloggers to increase engagement with young audiences can be considered significant areas for increasing competitiveness in B2C markets. 10. Large-scale modernization of industrial capital assets. Strategic approaches to increasing the competitiveness of Russian industrial enterprises are based on the principles of flexibility and the combination of state priorities (import substitution, digitalization) with market opportunities. Conclusion The study concluded that the strategic areas for improving competitiveness include digital transformation, R&D and innovation, greening and ESG, supply chain localization, export diversification, and investments in human capital. Key success factors include synergies between government programs (national projects, export support) and market opportunities, a focus on R&D and integration into international value chains, and the evolutionary implementation of ESG principles and digital technologies, taking into account infrastructure realities. Companies that combine adaptability, innovation, and cooperation will be able to strengthen their positions in the domestic market and enter new niches globally. Necessary conditions for implementing strategic areas for increasing the competitiveness of industrial enterprises include a systems approach, government support, and a balance between global trends and local specifics. It is also necessary to overcome the digital divide, regulatory barriers, the risk of creating a "government procurement market" with low innovation activity, and regional imbalances. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. 36 VOLUME 31 (07) ISSUE 07 2025 Acknowledgments The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES 1. Antonov G.D., Ivanova I.P., Tumin V.M. Managing the Competitiveness of an Organization. - Moscow: INFRA-M, 2012. - 300 p. 2. Asanova S.S. Formation and Implementation of Import Substitution Processes in an Innovative Economy. / Dis., Cand. Sciences (Econ.): 08.00.05. - Samara, 2021. - 174 p. 3. Gerber Yu.B., Nagorny S.V. 2022. Priorities for Industrial Development in the Sharing Economy. Natural Sciences and Humanities Research, 40(2): 69–74. 4. Gerber Yu.B., Balko S.V., Yakushev A.A. 2022. Digital format for the development of the food industry in modern economic conditions. Economy, entrepreneurship and law, 12(5): 1613–1624. 5. Mayorova K.S. 2021. Transformation of value creation processes of industrial enterprises in terms of technology digitalization. International research journal, 7-3(109): 123–132. 6. Kantemirova M.A., Dzakoev Z.L. Strategic approach to the development of enterprises in the regional processing sector // Fundamental research. 2015. No. 6-2. pp. 355–36 7. Mayorova K.S., Balashova E.S. Digital transition of industrial enterprises to a "smart" ecosystem. Industrial economics, 14(4): 433–444. 8. Spiridonov A.A., Fadeeva M.L., Tolstykh T.O. 2023. Strategic priorities of state support for import substitution in industry. Industrial Economics, 16(2): 166–175. СТРАТЕГИЧЕСКИЕ НАПРАВЛЕНИЯ ПОВЫШЕНИЯ КОНКУРЕНТОСПОСОБНОСТИ ПРЕДПРИЯТИЙ В КОНТЕКСТЕ ПРИОРИТЕТОВ ЭКОНОМИЧЕСКОГО РАЗВИТИЯ ОБРАБАТЫВАЮЩЕЙ ПРОМЫШЛЕННОСТИ Атиф Новрузов1, Рашад Алирзаев2 1Кандидат наук, доцент, Кафедра менеджмент, АГУНП. E-mail:[email protected]u atif.nov[email protected] 2Специальность Менеджмент. E-mail: resadelirzayev[email protected]m РЕЗЮМЕ VOLUME 31 (07) ISSUE 07 2025 37 Без повышения конкурентоспособности предприятия невозможно привлечь клиентов, получить необходимую выручку, сохранить устойчивое положение на рынке и даже существовать. Конкуренция заставляет каждое предприятие понимать потребительскую привлекательность своей продукции, ее качество, цены и послепродажное обслуживание. Конкуренцию следует рассматривать как определяющий фактор стабилизации цен, стимул к инновациям и средство вытеснения с рынка неэффективных хозяйствующих субъектов. Поэтому обеспечение необходимого уровня конкурентоспособности следует оценивать не только как функцию системы управления предприятием, но и как потенциальный результат эффективного функционирования всех его подразделений и подразделений. Ключевым фактором, способным защитить конкурентные позиции предприятия на рынке, является способность координировать взаимодействие всех его подразделений, что требует соответствующих подходов к планированию их деятельности. Компании, обладающие передовыми технологиями и инструментами управления, сегодня обладают большей рыночной властью, чем те, кто контролирует ресурсы. Поэтому конкурентоспособность предприятия необходимо управлять и планировать, обеспечивая ее эффективность и результативность. Перерабатывающие предприятия региона нуждаются в методологическом переходе от планирования преимущественно внутренних показателей эффективности и процессов к стратегическому планированию с учетом обеспечения конкурентоспособности на соответствующий период. Цель исследования – выявление стратегических направлений повышения конкурентоспособности промышленных предприятий в условиях внешних вызовов (санкций, технологических ограничений) и внутренних ограничений (износа активов, дефицита рабочей силы). Методология основана на анализе научных публикаций за 2020–2024 годы с использованием ключевых слов, связанных с развитием промышленности, и системного подхода к формулированию рекомендаций. Результаты показали, что ключевыми направлениями являются цифровая трансформация (внедрение IoT, AI и цифровых двойников), интеграция принципов ESG с Индустрией 5.0, локализация цепочек поставок, развитие НИОКР и сотрудничество с научными кластерами. Особое внимание уделено необходимости преодоления цифрового разрыва между крупными и малыми предприятиями, а также системным изменениям в инфраструктуре и управлении. В исследовании подчеркивается, что успех зависит от синергии технологических, институциональных и социальных преобразований, поддерживаемых государственными программами и адаптированных к мировым тенденциям. Ключевые слова: факторы конкурентоспособности предприятий, промышленность, приоритеты развития промышленности, экономика промышленности, стратегия роста конкурентоспособности. EMAL SƏNAYESİNİN İQTİSADİ İNKİŞAFININ PRİORİTETLƏRİ KONTEKSTİNDƏ MÜƏSSİSƏLƏRİN RƏQABƏT QABİLİYYƏTİNİN ARTIRILMASININ STRATEJİ İSTİQAMƏTLƏRİ Atif Novruzov2, Rashad Alirzayev2 1PhD, Dosent, Menecment kafedrası, ADNSU. E-mail: atif_novruzo[email protected] atif.nov[email protected].az 38 VOLUME 31 (07) ISSUE 07 2025 2Menecment ixtisası. E-mail: resadelirzay[email protected]m XÜLASƏ Rəqabət qabiliyyətini artırmadan müştəriləri cəlb etmək, lazımi gəlir əldə etmək, sabit bazar mövqeyini saxlamaq, hətta mövcud olmaq mümkün deyil. Rəqabət hər bir müəssisəni öz məhsullarının istehlakçı cəlbediciliyini, keyfiyyətini, qiymətlərini və satışdan sonrakı xidməti başa düşməyə məcbur edir. Rəqabət qiymətlərin sabitləşməsinin müəyyənedici amili, innovasiya üçün stimul və səmərəsiz təsərrüfat subyektlərini bazardan çıxarmaq vasitəsi kimi nəzərdən keçirilməlidir. Buna görə də, rəqabətqabiliyyətliliyin zəruri səviyyəsinin təmin edilməsi təkcə müəssisənin idarəetmə sisteminin funksiyası kimi deyil, həm də onun bütün bölmə və şöbələrinin səmərəli fəaliyyətinin potensial nəticəsi kimi qiymətləndirilməlidir. Müəssisənin bazarda rəqabət mövqeyinin qorunmasında əsas amil onun bütün bölmələrinin qarşılıqlı əlaqəsini əlaqələndirmək bacarığıdır ki, bu da onların fəaliyyətinin planlaşdırılmasına müvafiq yanaşmalar tələb edir. Qabaqcıl texnologiyalara və idarəetmə vasitələrinə malik olan şirkətlər bu gün resurslara nəzarət edənlərdən daha çox bazar gücünə malikdirlər. Buna görə də müəssisənin rəqabət qabiliyyəti idarə olunmalı və planlaşdırılmalı, onun effektivliyi və səmərəliliyi təmin edilməlidir. Regionun emal müəssisələri ilk növbədə daxili fəaliyyət göstəriciləri və prosesləri planlaşdırmaqdan müvafiq dövr üçün rəqabət qabiliyyətini nəzərə alan strateji planlaşdırmaya metodoloji keçid tələb edir. Tədqiqatın məqsədi xarici çağırışlar (sanksiyalar, texnoloji məhdudiyyətlər) və daxili məhdudiyyətlər (aktivlərin köhnəlməsi, işçi qüvvəsinin çatışmazlığı) şəraitində sənaye müəssisələrinin rəqabət qabiliyyətinin artırılması üçün strateji sahələri müəyyən etməkdir. Metodologiya sənaye inkişafı ilə bağlı açar sözlərdən və tövsiyələrin formalaşdırılmasına sistemli yanaşmadan istifadə etməklə 2020-2024-cü illər üzrə elmi nəşrlərin təhlilinə əsaslanır. Nəticələr göstərdi ki, əsas sahələrə rəqəmsal transformasiya (Əşyaların İnterneti, AI və rəqəmsal əkizlərin tətbiqi), ESG prinsiplərinin Sənaye 5.0 ilə inteqrasiyası, təchizat zəncirinin lokallaşdırılması, R&D inkişafı və elmi klasterlərlə əməkdaşlıq daxildir. İri və kiçik müəssisələr arasında rəqəmsal fərqin aradan qaldırılması, infrastruktur və idarəetmədə sistemli dəyişikliklərin aparılması zərurətinə xüsusi diqqət yetirilir. Tədqiqatda uğurun dövlət proqramları tərəfindən dəstəklənən və qlobal tendensiyalara uyğunlaşdırılan texnoloji, institusional və sosial transformasiyaların sinerjisindən asılı olduğu vurğulanır. Açar sözlər: müəssisənin rəqabətqabiliyyətliliyi amilləri, sənaye, sənaye inkişafı prioritetləri, sənaye iqtisadiyyatı, rəqabət qabiliyyətinin artım strategiyası. VOLUME 31 (07) ISSUE 07 2025 39 ASSESSMENT OF GEOTHERMAL ENERGY PROSPECTS IN AZERBAIJAN: A COMPARATIVE ANALYSIS WITH GLOBAL HOT SPRING AND GEOTHERMAL RESOURCE REGIONS Abusalam Mukhtarov Azerbaijan State Oil and Industry University, Power Engineering Department, Energy Production Technologies Faculty, PhD student Baku, Azerbaijan, [email protected] ABSTRACT This paper presents a comprehensive evaluation of Azerbaijan’s geothermal energy potential and compares it with leading global regions rich in hot-spring and geothermal resources. The study examines the country’s geological and hydrogeological settings, thermal gradients, and spatial distribution of geothermal fields to determine areas of high potential. It further analyzes current utilization levels, distinguishing between direct applications—such as district heating, greenhouse operations, and balneological uses—and indirect uses like electricity generation through binarycycle systems. Special attention is given to the promising opportunity of repurposing Azerbaijan’s extensive network of oil and gas wells for geothermal production, offering substantial reductions in exploration costs and environmental impact. A comparative analysis with Turkey, Georgia, Iceland, Japan, and the Philippines reveals key differences in reservoir temperatures, policy frameworks, technological maturity, and investment environments shaping geothermal development. Results indicate that Azerbaijan possesses considerable potential for direct-use geothermal projects, particularly in space heating and agricultural applications, while also showing long-term promise for integrating geothermal with solar energy in hybrid systems. The study concludes that, with the introduction of clear legislation, fiscal incentives, robust infrastructure planning, and international technological collaboration, geothermal energy could become a vital component of Azerbaijan’s sustainable energy portfolio. Strengthening this sector would not only diversify national energy resources but also contribute to significant reductions in greenhouse gas emissions and dependence on fossil fuels. Keywords: Geothermal energy, Azerbaijan, renewable energy, hot springs, direct use, indirect use, oil and gas wells, geothermal development, comparative study, sustainable energy Introduction Geothermal energy represents a renewable, environmentally sustainable, and constant source of energy derived from the Earth’s internal heat. Unlike solar and wind, which are intermittent, geothermal energy provides a stable and predictable supply, suitable for both electricity 39-45 Publication history Article received: 06.10.2025 Article accepted: 03.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-39 40 VOLUME 31 (07) ISSUE 07 2025 generation and direct thermal use. As the global demand for clean energy grows, geothermal systems are gaining renewed attention as a reliable complement to other renewable sources [1]. Azerbaijan, known primarily for its rich oil and gas reserves, also possesses substantial geothermal resources. The country’s position along active tectonic zones and its abundance of hot springs create promising conditions for geothermal development. However, compared to its hydrocarbon sector, geothermal energy remains underdeveloped. Exploring this resource offers Azerbaijan an opportunity to diversify its energy mix and reduce dependence on fossil fuels while taking advantage of its existing drilling expertise and infrastructure. This paper evaluates Azerbaijan’s geothermal resource potential and compares it with several hot spring and geothermal-rich countries. The comparison provides insight into how Azerbaijan can strategically develop geothermal energy for both direct and indirect uses while maintaining environmental balance and economic sustainability [2]. Geothermal Energy Potential of Azerbaijan Azerbaijan’s geothermal resources are closely linked to its complex geological setting, which includes active fault lines, sedimentary basins, and historical volcanic formations. The Azerbaijani Ministry of Energy (2025) reports a total estimated geothermal potential of 571.2 MWt (thermal) and 57.1 MWe (electric). The International Energy Agency (2024) estimates the technical potential to be as high as 800 MW, with 11 known geothermal zones identified across the country. These zones include Shamakhi–Gobustan, Masalli–Astara, Kalbajar–Lachin, Nakhchivan, and the Greater Caucasus foothills. Temperatures across these regions vary between 30 °C and 150 °C, with the highest gradients found in the Kalbajar–Lachin and Karabakh zones. The combination of tectonic activity and sedimentary aquifers makes Azerbaijan well suited for moderate-enthalpy geothermal projects, particularly for direct-use applications like heating, spa tourism, and greenhouse farming [3]. Direct use of geothermal energy in Azerbaijan includes applications for district heating, greenhouse heating, bathing, and spa tourism. Geothermal water temperatures in the Masalli– Astara and Talysh–Lankaran regions range between 30 °C and 64 °C, with flow rates up to 14,000 m³/day—sufficient for large-scale heating systems. Studies have shown that using geothermal water for greenhouses can reduce fossil fuel consumption by more than 30%, helping improve agricultural productivity and sustainability. The Renewable Heat Integration Project launched in 2025, supported by the Asian Development Bank, aims to introduce geothermal and solar energy into Azerbaijan’s urban district heating systems. Such efforts align with the national energy transition goals and demonstrate a growing institutional interest in renewable heat. Moreover, geothermal spas in regions such as Nakhchivan, Shamakhi, and Kalbajar are attracting domestic tourism, creating economic value while promoting clean energy utilization [3,4]. Indirect Use: Power Generation Potential While most of Azerbaijan’s geothermal resources fall within moderate temperature ranges, certain areas exhibit conditions suitable for binary cycle power generation. These include geothermal zones in Karabakh, Kalbajar, and Kurdamir, where temperatures exceed 100 °C. Binary plants are VOLUME 31 (07) ISSUE 07 2025 47 The term “users”, as illustrated in Figure 1, refers to various essential aircraft systems and subsystems that utilize ADIRS outputs. These include, but are not limited to, the Flight Warning Computers (FWC), the System Data Acquisition Concentrator (SDAC), and the Flight Management System (FMS) [1]. The importance of ADIRS arises from the need for continuous and accurate flight information under all operating conditions. As aircraft have evolved toward full digital control, the traditional independent gyroscopic and pitot-static instruments have been replaced by integrated systems capable of processing data in real time and distributing it through digital communication buses. ADIRS not only calculates and supplies flight parameters but also monitors their consistency and validity, ensuring that the aircraft’s automation systems operate with verified and reliable inputs [2]. Figure 1: Simplified functional layout of the Air Data Inertial Reference System (ADIRS). The Air Data Reference (ADR) unit within the ADIRU depends on several external sensors mounted on the aircraft structure to measure key atmospheric parameters, as illustrated in Fig. 2 and Fig.3. Figure 2: Pitot and Static Sensors Used in the Air Data Inertial Reference System (ADIRS). The pitot probes measure total air pressure, while the static ports measure ambient atmospheric pressure. Together, they enable the computation of airspeed, altitude, and vertical speed by the Air Data Reference (ADR) unit [11]. Pitot Probes: Measure total (stagnation) pressure created by the aircraft’s forward motion through the air. Together with static pressure, this enables the computation of airspeed. 48 VOLUME 31 (07) ISSUE 07 2025 Static Ports: Measure ambient static pressure outside the airflow, allowing determination of altitude and vertical speed when processed by the ADR. Figure 3: Temperature and Angle-of-Attack Sensors Used in the Air Data Inertial Reference System (ADIRS). The Total Air Temperature (TAT) sensors measure the temperature of the airstream, while the Angle-of-Attack (AOA) sensors detect the angular difference between the airflow and the aircraft’s reference line, providing critical data for stall protection and flight control systems [4]. Total Air Temperature (TAT) Sensors: Detect the temperature of the airstream, corrected for compressibility effects, which is used to calculate true airspeed and Mach number [15]. Angle-of-Attack (AOA) Sensors: Sense the angle between the airflow and the wing reference line, providing critical data for stall warning, flight control systems, and performance optimization. These measurements are transmitted to the ADR, which converts the raw pressures and temperatures into digital air data parameters such as calibrated airspeed, Mach number, barometric altitude, and air temperature. The processed data are then integrated with inertial information from the IR section of the ADIRU, producing a comprehensive and continuous set of flight parameters used throughout the aircraft avionics network. Integration with other avionics systems is one of the defining characteristics of ADIRS. Data produced by the system is transmitted to the Primary Flight Display (PFD) and Navigation Display (ND) for pilot reference, to the Electronic Centralized Aircraft Monitoring (ECAM) system for warning and diagnostic purposes, and to the Flight Management and Guidance Computer (FMGC) for flight planning and navigation [14]. Furthermore, ADIRS provides inputs to the autopilot and flight control computers, allowing the aircraft to maintain stable flight and follow programmed trajectories with high precision [2]. Each ADIRU (comprising ADR and IR components) provides flight data to the Display Management Computers (DMCs), Flight Augmentation Computers (FACs), Air Traffic Control (ATC) transponders, Weather Radar (WXR), and cockpit displays such as the Primary Flight Display (PFD), Navigation Display (ND), and ECAM system. The switching panel allows pilots to reconfigure data sources in case of a system failure, ensuring redundancy and continued data availability [6]. The purpose of this paper is to present a structured overview of the ADIRS, focusing on its functional organization, interconnection with other key aircraft systems, and its contribution to flight safety and operational efficiency. The following sections describe the system’s main components, explain its role in data distribution and monitoring, and discuss its integration with autopilot, flight management, and display systems in modern commercial aircraft. VOLUME 31 (07) ISSUE 07 2025 49 Figure 4: Interconnection of the Air Data Inertial Reference Units (ADIRUs) with major aircraft avionics systems. System Description The Air Data Inertial Reference System (ADIRS) is one of the core components of modern aircraft avionics. It combines air data and inertial reference functions within a single framework to provide accurate and continuous flight parameters to other onboard systems. The system consists of three independent Air Data Inertial Reference Units (ADIRUs), each integrating an Air Data Reference (ADR) section and an Inertial Reference (IR) section. A shared Control and Display Unit (CDU) allows the flight crew to monitor system status, perform alignments, and control operational modes [13]. Each ADIRU collects information from a set of external sensors, including pitot probes, static ports, angle of attack (AOA) sensors, and total air temperature (TAT) sensors. The ADR section processes this information to compute parameters such as pressure altitude, Mach number, air temperature, and barometric corrections. The IR section, on the other hand, uses gyroscopes and accelerometers to determine the aircraft’s attitude, heading, velocity, and position [15]. The outputs of the ADIRS are distributed to several aircraft systems, including the Primary Flight Display (PFD), Navigation Display (ND), Flight Control Computers (FCCs), Flight Management System (FMS), and Electronic Centralized Aircraft Monitoring (ECAM). Through digital data buses, the system ensures that all relevant subsystems receive continuous, redundant, and consistent flight data for safe operation [12]. To maintain reliability, ADIRS employs a triplex configuration, where each ADIRU can independently perform all functions. In the event of a failure in one unit, the remaining ADIRUs continue to supply validated information to the aircraft’s avionics network. This redundancy is critical to ensure uninterrupted data availability under all flight conditions [4]. 50 VOLUME 31 (07) ISSUE 07 2025 Figure 5: Flight-deck interfaces for ADIRS. Functional Integration of ADIRS with Aircraft Systems The Air Data Inertial Reference System supplies validated, continuous parameters to avionics users across the aircraft. This section summarizes how those parameters are consumed by key systems and how redundancy preserves service during faults. Autopilot and Flight-Control Computers: ADIRS provides attitude, angular-rate, heading/track, barometric altitude, and airspeed/Mach. The autopilot uses inertial outputs to stabilize pitch/roll/yaw loops and air-data outputs to regulate speed and altitude. If an ADR or IR channel is lost, crew switching assigns the standby ADIRU to the affected side so closed-loop control remains available [13,14]. Flight-Management and Guidance (FMS/FMGC): The FMGC uses inertial position/velocity/track from the IR portion and pressure-altitude/temperature from the ADR portion for navigation solutions, VNAV/LNAV mode logic, and performance scheduling. Hybridization with other NAV inputs (when available on type) further constrains position, while ADIRS remains the primary attitude/heading reference for guidance cues [13,14]. Figure 6: Flight Augmentation Computer (FAC) integration and control paths. Inputs from ADIRU 1/2/3 (air-data and inertial references) together with FMGC, ELAC, FWC, LGCIU and SFCC are processed by FAC 1/2. FAC outputs drive the rudder travel-limiting unit, VOLUME 31 (07) ISSUE 07 2025 51 yaw-damper actuators and rudder-trim actuator, with effects presented on the PFD/ECAM; a mechanical mixer transmits commands to the rudder and stabilizer. ADIRS supplies the speed/Mach, barometric altitude, attitude and rates used for these functions [12,14]. Primary Flight Display (PFD) and Navigation Display (ND) and ECAM: PFD/ND indications— attitude, airspeed, altitude, vertical speed, heading/track—are driven by ADIRS. Side-to-side consistency checks are supported by the triplex architecture; loss of one source is mitigated by reselecting a healthy ADIRU to maintain display continuity. ADIRS parameters feed the ECAM for warnings, cautions, and status messages. Typical effects include stall/overspeed alerts derived from air-data and discrepancy alerts when captain and first-officer references diverge. Channelspecific ADR/IR faults guide the crew to use the switching panel to restore a consistent source, as well as Pressure altitude from ADIRS is forwarded to the transponder for Mode C/S reporting. Accurate barometric altitude is essential for separation services and conformance monitoring [13,14]. Table 1. Mapping of ADIRS outputs to dependent systems. ADIRS Output Dependent system Primary use Attitude, rates Autopilot; Weather radar Control-loop stability; antenna stabilization Heading/track FMGC; PFD/ND Lateral guidance; display Barometric altitude PFD/ND; ATC Altitude indication; Mode C/S reporting CAS/Mach Autopilot; Augmentation Speed targets; protections Temperature Augmentation/Performance Speed schedule; performance calculation Operational Considerations IR alignment is performed on the ground via the MCDU with the IR selectors set to NAV; entering present position and initiating ALIGN IRS completes the process in approximately 10– 15 minutes depending on latitude [12]. In normal operation ADIRU 1 feeds captain-side users, ADIRU 2 feeds first-officer-side users, and ADIRU 3 is hot standby. The AIR DATA and ATT/HDG selectors on the overhead panel allow rapid reassignment following an ADR or IR fault to preserve indications and automation [13]. Representative flight-deck effects include stall/overspeed alerts, attitude/heading/altitude discrepancy messages between sides, and discrete ADR x FAULT or IR x FAULT alerts with associated ECAM procedures and switching actions [5,14]. Conclusions The Air Data Inertial Reference System forms the backbone of the aircraft’s information chain by combining air-data sensing and inertial referencing within redundant ADIRUs. Through continuous delivery of validated attitude, airspeed/Mach, and barometric altitude—as well as heading/track and position/velocity—the system enables stable autopilot operation, accurate flight-management guidance, and clear pilot situational awareness on the flight-deck displays [7,8,9,10]. Its integration with centralized monitoring allows timely detection and isolation of faults, while the triplex architecture and cockpit switching maintain service continuity following a 52 VOLUME 31 (07) ISSUE 07 2025 single-channel failure. The same outputs support surveillance and weather-radar stabilization, linking ADIRS performance directly to safety-of-flight functions. This paper has described the functional organization of ADR and IR, the role of external sensors, and the distribution of outputs to principal avionics users. The analysis highlights that the value of ADIRS lies not only in the precision of individual measurements but also in dependable availability and coherent distribution across the avionics network. Continued improvements in integration and monitoring can further enhance dispatch reliability, reduce maintenance burden, and support future automation features in transport-category aircraft. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES 1. C. R. McClary, “A fault-tolerant air data/inertial reference system,” IEEE Aerospace and Electronic Systems Magazine, May 1992. 2. J. R. Ryan, “Performance test results of the production fault-tolerant Air Data Inertial Reference System,” in Proc. IEEE/AIAA 13th Digital Avionics Systems Conference (DASC), 1994, pp. 371–376. 3. M. D. W. McIntyre and C. A. Gossett, “The Boeing 777 Fault-Tolerant Air Data and Inertial Reference System—A new venture in working together,” in Proceedings of IEEE, 1995, pp. 178–183. (Conference imprint and page range as shown in the PDF header.) 4. Y. C. (Bob) Yeh, “Design considerations in Boeing 777 fly-by-wire computers,” IEEE publication, year and venue not stated in the PDF copy. (Cite as an IEEE conference paper; include full venue and year if you have them.) VOLUME 31 (07) ISSUE 07 2025 53 5. Y. Chen and Z. Li, “Data hybridization computation analysis of aircraft Air Data Inertial Reference System,” in IEEE Conference Proceedings, 2011, ISBN 978-1-4577-0536-6. (Authors and IEEE imprint shown on the first page of the PDF.) 6. J. Noom, C. C. de Visser, N. S. Ramesh, and M. Verhaegen, “Simultaneously identifying the system dynamics and fault isolation for air data sensor failures: A convex approach,” IFAC PapersOnLine, vol. 58, no. 4, pp. 103–108, 2024. doi: 10.1016/j.ifacol.2024.07.201. 7. K. R. Rasmussen, J. J. Iversen, and J. Merrison, “The enhanced sensitivity of pitot tubes at low Reynolds number,” Flow Measurement and Instrumentation, vol. 101, art. 102750, Nov. 2024. doi: 10.1016/j.flowmeasinst.2024.102750. 8. M. Balzano, E. Rey, et al., “Detection and warning of ice crystals clogging pitot probes from total air temperature anomalies,” Aerospace Science and Technology, vol. 112, 2021. 9. J. Cole, “Cole-type pitot tubes and their application to aerometric measurements,” Journal of Instrumentation and Measurement Engineering, vol. 58, no. 3, 2019. 10. D. Eubank et al., “Failures of pitot tubes due to icing: Analysis of commercial incidents,” Flight Safety Quarterly, vol. 65, no. 2, pp. 91–103, 2020. 11. “Revisiting the pitot-static tubes in the standards,” ICAS Congress Proceedings, 2024 (ICAS Paper 0156). 12. R. P. G. Collinson, Introduction to Avionics Systems, 4th ed., Springer, 2023. (Use chs. “Air Data and Air Data Systems” and “Fly-By-Wire” for system context.) 13. M. Tooley and D. Wyatt, Aircraft Digital Electronic and Computer Systems, 3rd ed., ch. 6 “Computers,” CRC Press/Taylor & Francis, 2020. doi:10.1201/9781003215516-6. 14. K. Zhang and Z. Zhang, “Air-data-computer simulation and design credibility assessment considering ADC calculation model,” Aviation (Sciendo), 2024, pp. 1–10. 15. R. Sable, “Evolution of Total Air Temperature (TAT) Sensors,” AIP Conference Proceedings, vol. 3230, 130002, 2024. doi:10.1063/5.0234227. HAVA MƏLUMAT VƏ İNERSİAL REFERANS SİSTEMİ (ADIRS) VƏ ONUN MODERN TƏYYARƏ AVİONİKALARINDA İNTEQRASİYASI ÜZRƏ ÜMUMİ BAXIŞ Rauf Guliyev Müəllim, Doktorant, Hava Nəqliyyatı Fakültəsi, Avionika Bölməsi, Milli Aviasiya Akademiyası. Bakı, Azərbaycan. E-mail: [email protected] Orcid ID: 0009-0006-3872-8736 XÜLASƏ Bu məqalə Hava Məlumatı İnersial Referans Sistemi (ADIRS) və onun təyyarə əməliyyatındakı vacib rolunu nəzərdən keçirir, bu sistem Hava Məlumatı və İnersial Referans Funksiyalarını Hava Məlumatı və İnersial Referans Birliyində (ADIRU) birləşdirir, pitot-statik problar, temperatur sensorları, hücum bucağı probları və hava məlumatı modullarından məlumatları emal edir. Məqalədə sistemin kritik parametrləri – hava sürəti, yüksəklik, mövqe və istiqamət – kimi məlumatları bir neçə təyyarə alt sisteminə necə çatdırdığı qeyd olunur. Xüsusi diqqət, bu məlumatların düzgün nəzarət və naviqasiyanı təmin etdiyi avtopilot, uçuş idarəetmə kompüteri və uçuş nəzarət sistemləri ilə funksional əlaqələrə ayrılır. Müzakirə həmçinin sistemin əsas uçuş ekranları və Elektron Mərkəzləşdirilmiş Təyyarə Monitorinqi (ECAM) sistemi vasitəsilə kabinədəki göstəriciləri necə dəstəklədiyini və digər vahidlərə, məsələn, hava radarına və Hava 54 VOLUME 31 (07) ISSUE 07 2025 Nəqliyyatının İzləmə Transponderlərinə məlumat verdiyini vurğulayır. Ehtiyatlılıq və monitorinqin rolu, əməliyyat etibarlılığını qorumaqda xüsusi olaraq vurğulanır. Bu məqalənin məqsədi, ADIRS-in müasir təyyarənin əsas idarəetmə və monitorinq sistemlərini birləşdirən və dəstəkləyən əsas məlumat mənbəyi kimi necə fəaliyyət göstərdiyini, dəqiqlik, təhlükəsizlik və ümumi uçuş bütövlüyünü təmin etməsini izah etməkdir. Açar sözlər: Hava Məlumatı İnersial Referans Sistemi, Avtopilot, Uçuş İdarəetmələri, PitotStatik Prob. ОБЗОР СОВМЕЩЕННОЙ СИСТЕМЫ ВОЗДУШНЫХ СИГНАЛОВ И ИНЕРЦИАЛЬНОЙ СИСТЕМЫ (ADIRS) И ЕЁ ИНТЕГРАЦИЯ В СОВРЕМЕННЫХ АВИОНИКАХ САМОЛЕТОВ Рауф Гулиев Преподаватель, Докторант, Факультет воздушного транспорта, Кафедра Авионики, Национальная Авиационная Академия. Баку, Азербайджан. E-mail: [email protected] Orcid ID: 0009-0006-3872-8736 РЕЗЮМЕ В данной работе представлен обзор совмещенной системы воздушных сигналов и инерциальной системы (ADIRS) и её ключевой роли в эксплуатации самолетов, эта система объединяет функции инерциальной системы и потока воздушных данных в инерциальном блоке (ADIRU), обрабатывая информацию от питот-статических датчиков, датчиков температуры, датчиков угла атаки и аэроданных модулей. В работе подробно описывается, как система передает критические параметры – такие как воздушная скорость, высота, положение и курс – в несколько подсистем самолета. Особое внимание уделено её функциональным связям с ключевыми авионными системами, включая автопилот, бортовой компьютер управления полетом и системы управления полетом, где данные ADIRS обеспечивают точное управление и навигацию. В обсуждении также подчеркивается, как система поддерживает индикации в кабине через основные дисплеи полета и систему электронного централизованного мониторинга самолета (ECAM), предоставляя информацию другим единицам, таким как погодный радар и транспондеры управления воздушным движением. Особое внимание уделяется роли резервирования и логики мониторинга в поддержании эксплуатационной надежности. Цель этой работы – описать, как ADIRS функционирует в качестве основного источника данных, который соединяет и поддерживает основные системы управления и мониторинга современного самолета, обеспечивая точность, безопасность и общую целостность полета. Ключевые слова: Система инерциального ссылочного измерения аэроданных, автопилот, управление полетом, питот-статические датчики. VOLUME 31 (07) ISSUE 07 2025 55 CORROSION PROTECTION ASSURANCE IN THE CONSTRUCTION AND OPERATION OF TRUNK PIPELINES Zаmaddin Allakhverdiyev1, Latifa Kazimova2 1, 2Azerbaijan State Oil and Industry University, Department of Industrial Safety and Labor Protection, docent E-mail: [email protected], [email protected] ORCİD: 0000-0002-0254-1746 ABSTRACT The term corrosion originates from the Latin word “corrosio”, meaning erosion or degradation. Metal corrosion refers to their deterioration and becoming unserviceable as a result of chemical, electrochemical, or biochemical effects. Due to the reduction of the free energy of a construction material, metals exhibit thermodynamic instability. In essence, corrosion can be defined as the destruction of metals and alloys under the influence of the external environment. In some metals, the degradation process occurs not only on the surface but also within the material. This leads to the disruption of the crystal lattice structure and results in the loss of intrinsic properties. When impurities are abundant within the metal, galvanic couples may form on the surface, leading to localized points of attack and the development of pitting corrosion, which accelerates metal degradation. The economic damage caused by corrosion across different countries can be illustrated by several examples. According to Le Metayer, in 1953 the economic loss to Norway due to corrosion amounted to 180 million marks. In 1964, damages to France’s marine structures reached 80 million francs. Every year, biological corrosion results in a loss of 25 million dollars in Australia and 5 million dollars in New Zealand. In the United States, biofouling in the shipping industry causes an annual loss of 10 million dollars, while sulfate-reducing bacteria in underground pipelines cause damages estimated between 500–2000 million dollars annually. To protect the famous Eiffel Tower from corrosion, 70 tons of special paint and varnish are applied every three years. Generally, the surfaces of metals in their normal state and after corrosion differ significantly. However, certain types of corrosion are invisible to the naked eye. This phenomenon, known as intergranular corrosion (metal embrittlement), occurs due to the disruption of the crystal lattice structure of metals. Corrosion of metals is observed under various environmental conditions such as water, atmosphere, soil, acidic, and alkaline media. The electrochemical corrosion process occurs as a result of the formation of a double electric layer at the metal–environment interface. In some cases, chemical effects are accompanied by physical degradation, which is termed erosion–corrosion or fretting–corrosion. In the case of iron and its alloys, rusting occurs as hydrated corrosion products are formed from oxides. Non-ferrous metals also corrode, although they do not form rust. 55-65 Publication history Article received: 07.10.2025 Article accepted: 04.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-55 56 VOLUME 31 (07) ISSUE 07 2025 During the design and construction of pipelines, the protection of pipeline structures and foundations of pipes from environmental impacts must be ensured. Keywords: pipeline, metal, environment, protective coating, corrosion. Introduction Protection of pipelines from underground and atmospheric corrosion. During the design and construction of pipelines, issues related to protecting pipeline structures and foundations from the impact of environmental factors must be addressed. When constructing underground or aboveground pipelines, anti-erosion measures involve the use of subsurface protective materials. At the intersection of underground pipelines with other structures, the reinforced sections of non-flooded banks must be positioned at least 0.5 m above the level of floods that occur once every 50 years, as well as above the highest level of wave impact on the shore. In addition to the slopes of flooded banks, other adjacent sections of slopes‒ranging from 1 to 5 meters in length‒must be reinforced. The width of the reinforced shore zone is determined in the design process, depending on geological and hydrogeological conditions. If the pipeline route passes through landslide-prone areas, both the pipeline and the surrounding environment must be protected by installing the pipeline on elevated supports (piles or pillars installed through excavation or drilling). If the terrain along the pipeline route is affected by erosion or covered with cracks, these areas must be stabilized prior to construction. This ensures that preventive measures are implemented to protect the surrounding environment in the future. Methodology Depending on specific construction and operational conditions, two types of corrosion protection coatings are used for pipelines: reinforced and standard types. The reinforced coating type is applied to pipelines with a diameter of 1020 mm or to pipelines of any diameter under the following conditions: * When the pipeline route runs from south to north at an angle of approximately 50°; * When fertile soil in any region of the country is subject to salinization or alkalinization; * When the pipeline passes through swampy areas, black soils, or irrigated lands; * When the pipeline crosses underwater sections, river channels, motor roads, or railways; * When it intersects with other pipeline routes (the protective coating must extend 20 m on both sides of the intersection); * When crossing industrial or domestic wastewater discharge areas or solid waste dumping zones; * When intersecting with pipelines transporting liquids at a temperature of 313 K (40°C); * When located less than 1000 m from rivers, canals, lakes, reservoirs, or residential areas. To protect aboveground pipelines from atmospheric corrosion, various coatings such as varnish paints, treated fiberglass, metallic coverings, or consistent grease-based coatings are used. The total thickness of varnish paint coatings must not be less than 0.2 mm, and their electrical conductivity should not exceed 1 kV. The quality control of paint coating thickness is performed using instruments such as “MT41NÜ,” “TU 25-06.2500-83,” and “Krona-1R” (“TU 25-06.2515-83”). VOLUME 31 (07) ISSUE 07 2025 63 15. A.M. Kadyrov, V.S. Sapozhnikov. Neftepromyslovyye kompressory. Baku, Azneftiizdat, 1952, 332s. 16. M.P. Kalinushkin. Gidravlicheskiye mashiny i kholodil'nyye ustanovki. M., Gosstroyizdat, 1957, 219s. 17. V.I. Kiselev. Nasosy, kompressory, ventilyatory. M. Metallurgizdat, 1961, 400s. 18. Kompressory vozdushnyye i gazovyye. Katalog - katalog. M., Mashgiz, 1954, 166s. 19. Kontorovich B.V. Nasosy i pnevmomashiny. M. Metallurgizdat, 1956, 166s. 20. Metallicheskiye konstruktsii. Pod red. Belenia, 1961 g. 21. Metallicheskiye konstruktsii. Pod red. Belenia, 1985 g. 22. K.P. Seleznev i dr. Teoriya rascheta trubchatykh kompressorov. M. «Mashinostroyeniye», 1968, 406 s. 23. K.I. Strakhovich i dr. Kompressornyye mashiny. M., Gostorgizdat, 1961 g. 24. SNiP 2.05.06-85 Magistral'nyye truboprovody. 25. SNiP 2.04.12-86 Raschet prochnosti stal'nykh truboprovodov. 26. G.N. Smirnov, B.F. Goryunov, Ye.V. Kurlovich, S.N. Levachev, A.G. Sidorov. Porty i portovyye sooruzheniya. Moskva, Stroyizdat, 1979, 608s. MAGİSTRAL BORU KƏMƏRLƏRİNİN TİKİNTİSİ VƏ İSTİSMARI DÖVRÜNDƏ KORROZİYADAN MÜHAFİZƏNİN TƏMİN EDİLMƏSİ Zaməddin Allahverdiyev1, Lətifə Kazımova2 1, 2Azərbaycan Dövlət Neft və Sənaye Universiteti PHŞ, Sənaye thlükəsizliyi və əmək mühafizəsi kafedrası, dosent. E-mail: [email protected], [email protected] ORCİD: 0000-0002-0254-1746 XÜLASƏ Korroziya – latınca «Corrosio» sözündən götürülüb, mənası yeyilmə, dağılma deməkdir. Metalların korroziyası – onların kimyəvi, elektrokimyəvi, biokimyəvi təsir nəticəsində dağılaraq yararsız hala düşməsidir. Konstruksiyanın sərbəst enerjisinin azalması hesabına metalların termodinamiki davamsızlığ baş verir. Konkret şəkildə korroziya– xarici mühitin təsiri ilə metal və ərintilərinin dağılması deməkdir. Bəzi metallarda dağılma prosesi təkcə metalın səthində deyil, onun daxilində də baş verir. Bu isə metalın kristal qəfəsinin dağılması ilə nəticələnir və metal özünəməxsus xassələri itirir. Metalın tərkibində qarışıqlar çox olanda onun səthində qalvanik cütlərin yaranması nəticəsində kiçik nöqtələr əmələ gəlir və pittinq korroziyası baş verir, metal dağılmaya məruz qalır. Korroziya nəticəsində müxtəlif ölkələrin iqtisadiyyatına dəyən ziyanı bir neçə misalla göstərək: Le Metayepin məlumatına görə 1953-cü ildə Norveç iqtisadiyyatına korroziyadan dəyən ziyan 180 milyon markaya çatırdı. 1964-cü ildə Fransanın dəniz qurğularına dəyən zərər 80 milyon frank olmuşdur. Hər il Avstraliyada bioloji korroziyadan dəyən zərər 25milyon dollar, Yeni Zelandiyada 5 milyon dollar təşkil edir. ABŞ-da bioloji örtüyün gəmiçiliyə vurduğu ziyan ildə 10 milyon, yeraltı borularda sulfat reduksiyaedici mikrobların vurduğu ziyan isə ildə 5002000milyon dollara çatır. Məşhur Eyfel qülləsini korroziyadan qorumaq üçün hər üç ildən bir 70 ton xüsusi lak-boyaq maddəsi istifadə edilir. 64 VOLUME 31 (07) ISSUE 07 2025 Ümumiyyətlə, metalın adi və korroziyaya uğramış səthləri kəskin fərqlənir. Lakin elə korroziyalar var ki, onu adi gözlə görmək mümkün olmur. Bu kristalarası korroziya (metalın kövrəkləşməsi) adlanır və metalı təşkil edən kristal qəfəsin pozulması ilə baş verir. Müxtəlif ekoloji şəraitlərdə – suda, atmosferda, torpaqda, turşuda, qələvidə metalların korroziyaya uğraması müşahidə olunur. Elektrokimyəvi korroziya prosesi metal – mühit sərhəddində ikiqat elektrik təbəqəsinin əmələ gəlməsi nəticəsində baş verir. Bəzi hallarda kimyəvi təsir fiziki dağılma ilə müşahidə olunur. Bu korroziya erroziyası və ya frettinq-korroziya adlanır. Dəmir və onun ərintilərinin korroziyası zamanı əmələ gələn oksidlərinin hidratlaşmış korroziya məhsullvarı hesabına paslanma olur. Əlvan metallar korroziyaya uğrayır, lakin paslanmır. Boru kəmərlərinin layihələndirilməsi, çəkilməsi (tikintisi) zamanı, kəmərin qurğularının və boruların özüllərinin ətraf mühitin təsirindən qorunması məsələləri öz həllini tapmalıdır. Açar sözlər: boru kəmər, metal, ətraf mühit, qoruyucu örtük, korroziya. ЗАЩИТА ОТ КОРРОЗИИ ПРИ СТРОИТЕЛЬСТВЕ И ЭКСПЛУАТАЦИИ МАГИСТРАЛЬНЫХ ТРУБОПРОВОДОВ Замaддин Аллахвердиев1, Латифа Казымова2 1, 2Доцент, Азербайджанский государственный университет нефти и промышленности, E-mail: [email protected], [email protected] РЕЗЮМЕ Термин *коррозия* происходит от латинского слова «corrosio», что означает разъедание, разрушение. Коррозия металлов ‒ это их разрушение и потеря эксплуатационной пригодности в результате химического, электрохимического или биохимического воздействия. За счёт уменьшения свободной энергии конструкции металлы проявляют термодинамическую неустойчивость. В сущности, коррозия определяется как разрушение металлов и сплавов под воздействием внешней среды. У некоторых металлов процесс разрушения происходит не только на поверхности, но и внутри материала. Это приводит к нарушению кристаллической решётки и утрате металлом присущих ему свойств. При большом количестве примесей в металле на его поверхности возникают гальванические пары, образуются локальные точки разрушения и развивается питтинговая коррозия, что ускоряет разрушение металла. Экономический ущерб от коррозии в разных странах можно проиллюстрировать несколькими примерами. По данным Ле Метайе, в 1953 году ущерб экономике Норвегии от коррозии составил 180 миллионов марок. В 1964 году ущерб морским сооружениям Франции достиг 80 миллионов франков. Ежегодно биологическая коррозия наносит убытки в размере 25 миллионов долларов в Австралии и 5 миллионов долларов в Новой Зеландии. В США ущерб от биологического обрастания в судоходстве составляет 10 миллионов долларов в год, а от действия сульфатредуцирующих бактерий в подземных трубопроводах — от 500 до 2000 миллионов долларов ежегодно. Для защиты знаменитой Эйфелевой башни от коррозии каждые три года используется 70 тонн специальных лакокрасочных материалов. VOLUME 31 (07) ISSUE 07 2025 65 В целом, поверхность металла в обычном состоянии и после коррозии резко отличается. Однако существуют виды коррозии, которые невозможно увидеть невооружённым глазом. Это так называемая межкристаллитная коррозия (охрупчивание металла), возникающая вследствие нарушения кристаллической решётки металла. Коррозия металлов наблюдается в различных экологических условиях — в воде, атмосфере, почве, кислотах и щёлочах. Электрохимическая коррозия протекает в результате образования двойного электрического слоя на границе металл–среда. В некоторых случаях химическое воздействие сопровождается физическим разрушением. Этот процесс называется эрозионной или фреттинг-коррозией. В случае железа и его сплавов ржавление происходит за счёт образования гидратированных продуктов коррозии оксидов. Цветные металлы также подвергаются коррозии, хотя не ржавеют. При проектировании и строительстве магистральных трубопроводов необходимо обеспечить защиту трубопроводных сооружений и фундаментов труб от воздействия окружающей среды. Ключевые слова: трубопровод, металл, окружающая среда, защитное покрытие, коррозия. 66 VOLUME 31 (07) ISSUE 07 2025 DETERMINATION OF OIL POLLUTION OF WATER SURFACE USING AN UNMANNED AERIAL VEHICLE (UAV) Axıra Sultanova Associate professor, Azerbaijan State Oil and Industry University, Doctor of Philosophy in Technology, Institute of Control Systems of ANAS. E-mail: [email protected]u ABSTRACT The article presents an algorithm for determining oil pollution of water surfaces based on indepth study using multispectral images obtained from a camera on unmanned aerial vehicles (UAVs).The article pays special attention to the issues of accuracy and speed of the algorithm. The developed method has a high information processing speed and can be successfully applied in various climatic conditions. The results show that the proposed algorithm is able to automatically detect even minor contamination of water surfaces, which makes it possible to quickly respond to environmental disasters and minimize their consequences. The article examines the algorithm for detecting oil pollution on the water surface as part of ecological monitoring. The problem of detecting oil pollution by traditional methods requires significant time and financial costs, which reduces the effectiveness of their operational monitoring. Modern approaches to monitoring increasingly involve the use of unmanned aerial vehicles (UAVs) with multispectral cameras and deep learning algorithms, which allows to significantly reduce the response time to environmental disasters. The integration of deep learning technologies allows not only to automate the process of pollution detection, but also to increase its accuracy due to the analysis of large volumes of data. The purpose of this research is to develop an effective algorithm for automated oil pollution monitoring. Keywords: Unmanned Aerial Vehicle (UAV), monitoring, mapping, vision systems, geoinformation system, machine learning, multispectral research. Introduction The spread of petroleum products and crude oil into the environment is one of the most serious threats to both water resources and soil. These phenomena occur as a result of malfunctions of tankers, pipelines or oil rigs, as well as on water surfaces due to accidents. Difficult atmospheric conditions contribute to the unpredictable behavior of oil spills, which requires the development of effective models to predict their spread. Creating a model requires monitoring and environmental impact assessment. In this regard, satellite photography, the use of images obtained from cameras of modern unmanned aerial vehicle (UAV) aircraft, has become the main tool for detecting and analyzing the consequences of oil spills. With the development and widespread use of UAVs and digital photogrammetric cameras over the past 10 years, the 66-73 Publication history Article received: 07.10.2025 Article accepted: 04.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-66 VOLUME 31 (07) ISSUE 07 2025 67 importance of photogrammetry has increased and become a more suitable solution tool for map production. UAV platforms are today an important source of information in the production of photogrammetric information, allowing inspection, control and analysis for different disciplines and different areas of application. UAVs make significant contributions to areas such as mapping, mining, geology, construction and environmental engineering, as they can be easily used in terms of fast and cost-effective control of modern data. Thanks to emerging photogrammetric sensor, platform and remote reception technologies, UAVs are becoming increasingly widespread as they provide higher spatial and temporal resolution capabilities than classical aerial photogrammetry. Due to this achievement in UAV photogrammetry, it is currently widely used in open-pit mining enterprises in many types of activities such as mapping, 3D modeling, quantification of production and decapage, and geological mapping. In addition to these studies, UAV photogrammetry began to be used after 2010 to monitor plate movement, large-scale shifts and deformations. The article discusses an algorithm for detecting oil pollution on the water surface in the framework of environmental monitoring. The problem of detecting oil spills using traditional methods requires significant time and financial costs, which makes them less effective for operational control. Modern monitoring approaches increasingly require the use of unmanned aerial vehicles (UAVs) using multispectral cameras and deep learning algorithms, which can significantly reduce the response time to environmental disasters. The integration of deep learning technologies allows not only to automate the pollution detection process, but also to increase its accuracy by analyzing large amounts of data. This research is aimed at developing an effective algorithm for automated monitoring of oil pollution. Models and methods. There are modern approaches and various methods with unique properties, advantages and limitations for detecting and controlling water surface pollution. Traditional monitoring tools, developed over the years, have a number of significant drawbacks in the era of global informatization. Modern interactive tools allow you to build maps based on operations with multidimensional data (hypercubes), facilitating the collection and processing of information about the environment. In modern monitoring, most of the initial data used for analysis is obtained through space observations [1]. In [2], a highly efficient satellite tracking model based on remotely obtained data is proposed. This model was used to obtain the basic quality parameters. [3] demonstrates the use of data processing collected in real time. Their research focuses on the relationship between the environment and the digital processing of the resulting graphics and images. In [4], satellite imagery was used to track water pollution. Satellite monitoring will make it possible to identify the sources of pollution, measure its scale and predict the spread parameters, which will make it possible to map the spread of oil spills [5]. A key aspect of many existing studies is the processing of high-quality satellite images [6]. . Satellite monitoring makes it possible to detect and track pollution in large areas. Some satellites are equipped with special sensors that can detect various types of pollutants. However, this technology can be expensive and requires complex data analysis. [6-7]. Satellite images do not always meet the monitoring requirements. The use of unmanned aerial vehicles eliminates these disadvantages and can provide good conditions for monitoring water quality due to the flexibility and portability of numerous or highly spectral sensors [7-9]. [10] describes the development and application of multi-purpose UAVs for oil slick detection and control. 68 VOLUME 31 (07) ISSUE 07 2025 In [11-12], a model of a multidronic system for detecting oil spills in seawater is presented. The system includes machine vision and a lightweight algorithm that provides autonomous tracking via certified drones. An algorithm for detecting oil pollution. The amount of water pollution from oil and petroleum products is quite high. Millions of tons of oil pollute the sea waters and oceans every year. Accidents of oil tankers, accidents at oil wells, and the discharge of oil wastewater into the seas lead to pollution of marine ecological systems. Petroleum products released into the water undergo chemical photochemical and bacteriological decomposition. However, it takes a long time to naturally neutralize them. In order to properly detect oil pollution, in addition to obtaining high-quality images, it is necessary to perform image processing to localize the areas of interest. This will avoid oil pollution. This will avoid oil pollution. All areas known to be potential oil spills must be re-checked and confirmed. In addition to identifying precontamination sites, researchers are tasked with determining the geometric parameters of spills in order to make prompt and effective decisions in environmental monitoring systems. To solve these tasks, it is necessary to develop an integrated approach that will be based on the application of automated image processing and will include elements of machine learning. Using this approach will increase the accuracy of detecting oil pollution on the water surface. It is also important to consider various factors such as environmental changes, weather conditions, and features. In addition, system integration requires verification, which will use additional data, such as spectral analysis or remote sensing results, to increase the reliability of evidence of contamination. To evaluate the effectiveness of artificial intelligence models designed to detect water pollution, two main indicators are selected: the Dice coefficient and the Jacquard coefficient. The value of the suggested sizes ranges from 0 to 1. Here 1 shows a complete match. The Dice coefficient is the size that reflects the similarity between two samples. In the context of image segmentation, it reflects the mathematical relationship between the projected mask and the real (real) mask of the object: Dice = |X| + |Y|2 × |X ∩ Y|, In research related to the development of effective environmental monitoring systems, these indicators are used to assess the accuracy of models. Artificial intelligence models play an important role in determining the boundaries of oil spills on the water surface and assessing quality. The high values of the Dice and Jaccard coefficients indicate the feasibility of the model and clearly define the boundaries of the variance. The introduction of neural networks makes it possible to automatically analyze large amounts of data obtained from UAVs using computer vision techniques and identify complex data. Multispectral images are used to improve recognition accuracy and informativeness. The multispectral images from the UAV include additional information for recognizing and classifying objects in the image. Thus, the use of multispectral data significantly improves the accuracy and detail of segmentation (Fig.1). VOLUME 31 (07) ISSUE 07 2025 69 Figure 1: Investigation of the contaminated surface. Optimization methods play an important role in artificial neural networks, which significantly affect the learning process. In the process of training a neural network, the final accuracy is determined by the ratio of the weights of artificial neurons to the loss function, which must be minimized in each cycle. As optimization proceeds at a rapid pace and approaches a global minimum, recognition accuracy increases and training time decreases. The graph of the resulting image after training the neural network is shown below (Fig. 2). (The learning rate is 0.001 cycles) Figure 2: Accuracy graph after training. 70 VOLUME 31 (07) ISSUE 07 2025 The neural network was trained through a dataset created based on N images. The images are images taken during aerial photography. A convolutional deep learning neural network is used to solve the problems of segmentation of images of oil slicks on the surface of water (ocean, sea, lake). Conclusion The results of the study showed that the use of unmanned aerial vehicles (UAVs) and deep learning technologies makes it possible to effectively and accurately identify oil pollution on water surfaces. The article analyzes the problems of oil spill detection and segmentation using UAVs and deep learning structures. The segmentation of images obtained from the UAV is carried out using a convolutional neural network (CNN). The proposed algorithm has the ability to quickly respond to accidents and spills, detect even minimal spills with high accuracy, access to remote and human-hazardous places, the ability to collect and analyze large amounts of data in real time, automate processes in hazardous areas without human participation, etc. it has been proved that there is a need for wide application in the implementation of such processes. The accuracy of recognition of these structures on the water surface demonstrates the effectiveness of the algorithms used. A new algorithm has been proposed using a more complex neural network model and image enhancement techniques (CNNs). Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES VOLUME 31 (07) ISSUE 07 2025 71 1. Sidoryakina V.V. Matematicheskaya model' protsessa rasprostraneniya neftyanykh zagryazneniy v pribrezhnykh morskikh ekosistemakh.Computational Mathematics and Information Technologies. 2023;7(4):39–46. https://doi.org/10.23947/2587-8999-2023-74-39-46 2. Pogorelov V. A. Perspektivy primeneniya bespilotnykh letatel'nykh apparatov v stroitel'stve // Inzhenernyy vestnik Dona, 2016, №1. URL: ivdon.ru/ru/magazine/archive/n1y2016/3571. 3. Sanders, D., 2015. Using Drones for Pipeline Operations. The Northeast ONG Marketplace, pp. 8-9. URL: ongmarketplace.com/wpcontent/uploads/2015/08/OGMidstream-August-2015-3.pdf. 4. Gomez, C., Green, D., 2015. Small-Scale Airborne Platforms for Oil and Gas Pipeline Monitoring and Mapping. University of Aberdeen Report. 54 p. URL: abdn.ac.uk/geosciences/documents/UAV_Report_Redwing_Final_Appendix_Upd ate.pdf 5. Korkishko A. N., Rakhmatullin SH. I., Karamyshev V. G. Lokatsiya utechek nefti, nefteproduktov i neftyanykh uglevodorodnykh zhidkostey na magistral'nykh truboprovodakh // Zhurnal «Problemy sbora, podgotovki i transportirovki nefti i nefteproduktov», 2011, №2. S. 142-147. URL: elibrary.ru/item.asp?id=16380139 6. Mityagina M., Lavrova O. Sputnikovyy monitoring zagryazneniya poverkhnosti Chernogo morya // IEEE International Geoscience and Remote Sensing Symposium (IGARSS). 2015. С. 2291–2294. 7. Ofitserov V., Konushin A. Segmentatsiya izobrazheniy vysokogo razresheniya s ispol'zovaniyem modeley glubokogo obucheniya // International Journal of Open Information Technologies. 2024. Vol. 12 (6). С. 57–64. 8. Prochazka A. et al. Satellite image processing and air pollution detection // IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings (Cat. No. 00CH37100). 2000. Vol. 6. Pp. 2282–2285. 9. Cheng K., Chan S., Lee J.H. Remote sensing of coastal algal blooms using unmanned aerial vehicles (UAVs) // Marine Pollution Bulletin. 2020. Vol. 152. P. 110889. 10. Maashri A., Ghommam J., Saleem A., Nasiri N. A multidrone system for oil spill detection: A simulation and emulation platform // 22nd International Conference on Control. 11. T. YA. Gladkikh, Obnaruzheniye neftyanykh zagryazneniy morskikh poverkhnostey s pomoshch'yu BPLA i mul'tispektral'nykh izobrazheniy na osnove tekhnologiy glubokogo obucheniya, Komp. nanotekhnologii., 2024, tom 11, vypusk 5, 152–160 12. Muratov M.V., Konov D.S., Petrov D.I., Petrov I.B. Primeneniye svertochnykh neyronnykh setey dlya poiska i opredeleniya fizicheskikh kharakteristik neodnorodnostey geologicheskoy sredy na osnove seysmicheskikh dannykh. Matematicheskiye zapiski SVFU. 2023;30(1):101–113. (Na russk.). https://doi.org/10.25587/SVFU.2023.87.50.008 PİLOTSUZ UÇUŞ APARATININ (PUA) TƏTBİQİ İLƏ SU SƏTHİNİN NEFTLƏ ÇİRKLİLİYİNİN MÜƏYYƏNLƏŞDİRİLMƏSİ Axirə Sultanova Dosent, Azərbaycan Dövlət Neft və Sənaye Universiteti, AMEA İdarəetmə Sistemləri İnstitutu, texnika elmləri namizədi. E-mail: sax[email protected] 72 VOLUME 31 (07) ISSUE 07 2025 XÜLASƏ Məqalədə pilotsuz uçuş aparatlarında (İHA) kameradan alınan multispektral şəkillərindən istifadə edərək dərin öyrənmə əsasında su səthlərinin neft çirkliliyinin müəyyənləşdirilməsi üçün bir alqoritm təqdim edir. Məqalədə alqoritmin dəqiqliyi və sürəti məsələlərinə xüsusi diqqət yetirilir. Hazırlanmış metod yüksək məlumat emal sürətinə malikdir və müxtəlif iqlim şəraitində uğurla tətbiq oluna bilər. Nəticələr göstərir ki, təklif olunan alqoritm ekoloji fəlakətlərə tez reaksiya verməyə və nəticələrini minimuma endirməyə imkan verən su səthlərinin hətta kiçik çirklənməsini avtomatik olaraq aşkar edə bilir. Məqalədə ətraf mühitin monitorinqi çərçivəsində suyun səthində neft çirkliliyinin aşkarlanması üçün bir alqoritm araşdırılır. Neft ləkələrinin ənənəvi üsullarla müəyyənləşdirilməsi problemi əhəmiyyətli vaxt tələb edir və maliyyə xərcləri, onların əməliyyat monitorinqi üçün daha az təsirli edir. Monitorinq aparılmasında tətbiq olunan müasir yanaşmalar getdikcə çox spektral kameralar və dərin öyrənmə alqoritmlərindən istifadə edən pilotsuz uçuş aparatlarının (İHA) istifadəsini tələb edir ki, bu da ekoloji fəlakətlərə cavab müddətini əhəmiyyətli dərəcədə azalda bilir. Dərin öyrənmə texnologiyalarının inteqrasiyası yalnız çirklənmənin aşkarlanması prosesini avtomatlaşdırmağa deyil, həm də böyük miqdarda məlumatların təhlili ilə dəqiqliyini yaxşılaşdırmağa imkan verir. Bu tədqiqat neft çirklənməsinin avtomatlaşdırılmış monitorinqi üçün effektiv bir alqoritm hazırlamağa yönəlmişdir. Açar sözlər: Pilotsuz uçuş aparatı (PUA), monitorinq ,kartoqram, görmə sistemləri, geoinformasiya sistemi, maşın öyrənmə, multispektral tədqiqat. ОПРЕДЕЛЕНИЕ НЕФТЯНОГО ЗАГРЯЗНЕНИЯ ВОДНОЙ ПОВЕРХНОСТИ С ПОМОЩЬЮ БЕСПИЛОТНОГО ЛЕТАТЕЛЬНОГО АППАРАТА (БПЛА) Ахира Султанова Доцент, Азербайджанский Государственный Университет Нефти и Промышленности, Институт систем управления НАНА, кандидат технических наук. Эл. aдрес: [email protected] РЕЗЮМЕ В статье представлен алгоритм определения нефтяного загрязнения водных поверхностей на основе глубокого изучения с использованием мультиспектральных изображений, полученных с камеры на беспилотных летательных аппаратах (БПЛА). В статье особое внимание уделено вопросам точности и скорости работы алгоритма. Разработанный метод имеет высокую скорость обработки информации и может успешно применяться в различных климатических условиях. Результаты показывают, что предложенный алгоритм способен автоматически обнаруживать даже незначительное загрязнение водных поверхностей, что позволяет быстро реагировать на экологические катастрофы и минимизировать их последствия. В статье исследуется алгоритм обнаружения нефтяных загрязнений на водной поверхности в рамках экологического мониторинга. Проблема обнаружения нефтяных загрязнений традиционными методами требует значительных временных и финансовых затрат, что снижает эффективность их оперативного мониторинга. Современные подходы к мониторингу всё чаще предполагают использование беспилотных летательных VOLUME 31 (07) ISSUE 07 2025 79 This study examined the thermal and operational characteristics of three refinery furnace configurations — box-type, cylindrical, and twin-cell — focusing on their heat flux distribution patterns and major performance issues. The Results 1. Burner Optimization Necessity. The analysis of thermal behavior across all furnace types confirmed that burner configuration and flame geometry play a dominant role in determining overall furnace performance. 2. Heat Flux Distribution as a Key Efficiency Indicator. Among all configurations, the most stable performance was observed when heat flux variation along the tube surface remained below ±10% of the mean value. Larger deviations led to measurable efficiency loss and higher tube metal temperatures. 3. Thermal Imbalance in Twin-Cell Design. The twin-cell furnace configuration, while advantageous for redundancy, exhibited susceptibility to inter-cell heat flux imbalance. 4. Impact on Emission Characteristics. Regions of elevated local temperature, particularly near flame impingement or hot spot zones, were directly correlated with increased thermal Nox formation. Table 1. Furnaces types, main problems and mitigations methods. Furnace Type Typical Application / Max Pressure / Max Temperature Main Problem Mitigation Method Box-Type Furnace Used in crude heaters, visbreaker feed heaters. Max pressure: 20–30 bar Max temperature: 850–1150 °C Flame impingement on tube walls causing local overheating and metal damage. Adjust burner tilt and spacing, use flame shields, implement lowNox burners with staged air injection. Cylindrical (Vertical) Furnace Common in reformers, hydrocrackers, and hydrogen units. Max pressure: 35– 45 bar Max temperature: 950–1050 °C Localized hot spots due to uneven heat flux and flue gas maldistribution. Maintain burner symmetry, optimize coil arrangement, apply CFD modeling for radiation uniformity. Twin-Cell Furnace Large-capacity crude or feed heaters requiring redundancy and continuous operation. Max pressure: 25–40 bar Max temperature: 900–1000 °C Inter-cell heat flux imbalance leading to unequal outlet temperatures and efficiency loss. Independent air/fuel control per cell, draft balancing, flame imaging and thermographic monitoring. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments 80 VOLUME 31 (07) ISSUE 07 2025 The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES 1. API Standard 560 – Fired Heaters for General Refinery Service, 5th Edition, American Petroleum Institute, Washington D.C., 2021. 2. V. Ganapathy, Industrial Boilers and Heat Recovery Steam Generators: Design, Applications, and Calculations, Marcel Dekker Inc., New York, 2003. 3. S. Mokhatab, W.A. Poe, and J.Y. Mak, Handbook of Natural Gas Transmission and Processing, 4th Edition, Gulf Professional Publishing, 2019. 4. Mustafa Tutar, C. Emre Üstün et al., “Optimized CFD Modelling and Validation of Radiation Section of an Industrial Top-Fired SMR Furnace,” 2025. 5. Y. Zhang et al., “CFD Analysis and Optimization of Furnace Burners for Nox Reduction in Refinery Applications,” Applied Thermal Engineering, Vol. 193, 2021, 117023. ИССЛЕДОВАНИЕ ТЕПЛОВОЙ ЭФФЕКТИВНОСТИ И ЭКСПЛУАТАЦИОННЫХ ПРОБЛЕМ ПЕЧЕЙ НЕФТЕПЕРЕРАБАТЫВАЮЩЕЙ ПРОМЫШЛЕННОСТИ Тамилла Ханкишиева1, Джавид Мустафаев2 1Доктор философии по технике, кафедра «Промышленные машины», Азербайджанский Государственный Университет Нефти и Промышленности, Email: tamilla.khan[email protected] 2Аспирант, кафедра «Промышленное машиностроение», Азербайджанский Государственный Университет Нефти и Промышленности, Азербайджан. Эл почты: javid.a.mu[email protected] РЕЗЮМЕ В этом документе представлен всесторонний обзор литературы, научных исследований и отраслевых стандартов, относящихся к печи с пламенным нагревом. Печи с пламенным нагревом играют ключевую роль в нефтеперерабатывающей промышленности, обеспечивая тепловую энергию, необходимую для таких процессов, как атмосферная и вакуумная перегонка нефти, каталитический риформинг, гидрокрекинг и термический крекинг. Поскольку эти установки являются одновременно крупными потребителями VOLUME 31 (07) ISSUE 07 2025 81 энергии и источниками выбросов, их конструкция и эксплуатационные характеристики имеют решающее значение для эффективности, безопасности и экологической устойчивости. Несмотря на широкое применение, такие печи подвержены ряду эксплуатационных проблем: удар пламени по трубам (flame impingement), неравномерное распределение теплового потока, закоксовывание труб, разрушение огнеупорной футеровки и чрезмерное образование оксидов азота (NOx). Эти факторы приводят к повышенному расходу топлива, сокращению срока службы оборудования и росту эксплуатационных затрат. В данной работе проведён сравнительный анализ трёх распространённых типов печей, применяемых на нефтеперерабатывающих заводах: коробчатого, цилиндрического и двухкамерного. Для каждого типа описаны основные принципы конструкции и типичные условия работы, а также рассмотрены наиболее часто встречающиеся эксплуатационные проблемы. В целом результаты исследования показывают, что систематическая оценка различных типов печей и целенаправленные инженерные улучшения могут существенно повысить их техническую работоспособность и энергоэффективность. Совмещение традиционных методов проектирования с современными технологиями моделирования и материаловедения позволяет снизить тепловые потери, уменьшить выбросы и продлить срок службы нагревательного оборудования. Ключевые слова: Печи нефтепереработки, Коробчатого, Цилиндрическая печь, Двухкамерная печь, Энергоэффективность, Low-Nox, Удар пламени. NEFT EMALI SOBALARINDA İSTİLİK SƏMƏRƏLİLİYİNİN VƏ ƏMƏLİYYAT ÇƏTİNLİKLƏRİNİN TƏDQİQİ Tamilla Xankişiyeva1, Cavid Mustafayev2 1“Sənaye maşınları” kafedrasının müəllimi, Azərbaycan Dövlət Neft və Sənaye Universiteti, texnika üzrə fəlsəfə doktoru, Email: [email protected] 2Doktorant, "Sənaye maşınları" Departamenti, Azərbaycan Neft və Sənaye Universiteti, Azərbaycan. Email id: [email protected] XÜLASƏ Bu məqalə neft emalı zavodlarında istifadə olunan istilik sobaları barədə ədəbiyyat, araşdırma materialları və sənayə standartları üzrə ətraflı icmalı əks etdirir. İstiliklə işləyən sobalar neft emalı sənayesində mühüm rol oynayır və xam neftin distillasiyası, katalitik reforminq, hidrokraking və termiki kraking kimi proseslər üçün tələb olunan istilik enerjisini təmin edir. Bu sobalar həm yüksək enerji istehlakçıları, həm də əhəmiyyətli emissiya mənbələri olduqlarına görə, onların layihələndirilməsi və istismar göstəriciləri enerji səmərəliliyi, təhlükəsizlik və ekoloji dayanıqlılıq baxımından xüsusi əhəmiyyət daşıyır. Geniş tətbiq sahəsinə malik olmalarına baxmayaraq, bu avadanlıqlar bir sıra əməliyyat problemlərinə məruz qalır: boru səthlərinə alovun birbaşa təsiri, istilik axınının qeyri-bərabər paylanması, borularda kokslaşma, odadavamlı materialların deqradasiyası və azot oksidlərinin (NOx) həddindən artıq yaranması. Bu problemlər yanacaq sərfiyyatının artmasına, avadanlığın istismar müddətinin azalmasına və texniki xidmət xərclərinin yüksəlməsinə gətirib çıxarır. Bu məqalədə neft emalı müəssisələrində istifadə olunan üç əsas soba 82 VOLUME 31 (07) ISSUE 07 2025 konfiqurasiyası – qutu tipli, silindrik və iki kameralı sobaların müqayisəli təhlili təqdim olunur. Hər bir soba növü üzrə əsas layihə prinsipləri və tipik iş şəraiti izah edilmiş, həmçinin əməliyyat zamanı müşahidə olunan əsas problemlər təhlil edilmişdir. Ümumilikdə aparılan tədqiqat göstərir ki, soba növlərinin texniki və termodinamik xüsusiyyətlərinin sistematik qiymətləndirilməsi, eləcə də layihə və istismar mərhələsində məqsədyönlü optimallaşdırma tədbirlərinin tətbiqi bu qurğuların enerji səmərəliliyini və texniki işqabiliyyətini əhəmiyyətli dərəcədə artırır. Ənənəvi dizayn yanaşmalarının müasir simulyasiya üsulları və qabaqcıl material texnologiyaları ilə birləşdirilməsi enerji itkilərinin azaldılmasına, emissiyaların minimuma endirilməsinə və soba avadanlıqlarının xidmət müddətinin uzadılmasına şərait yaradır. Açar sözlər: Neft emalı sobaları, Qutu tipli soba, Silindrik soba, İki kameralı soba, Enerji səmərəliliyi, Aşağı NOx, Alovun boruya təsiri. VOLUME 31 (07) ISSUE 07 2025 83 METHOD OF ANTIPHASE OPERATION OF PRODUCTION AND INJECTION WELLS Yevgeniya Mammadova1, Emin Makhmudov2 1,2Azerbaijan State Oil and Industry University, 1,2Department of Oil and Gas Engineering 1Associate professor, PhD, [email protected],https://orcid.org/0000-0001-5054-5701 2Master, Azerbaijan State Oil and Industry University ABSTRACT This paper examines the technology of cyclic counter-phase operation of production and injection wells as a logical extension of the unsteady waterflooding method used to enhance reservoir oil recovery. A major limiting factor in the application of conventional unsteady waterflooding is the high current water cut of produced fluids. The paper proposes an improved technology that combines cyclic water injection with periodic production well operation, enabling reduction of produced water volumes and an increase in recoverable oil reserves. It is well recognized that unsteady waterflooding (UW) methods are most effective in thick, layered, heterogeneous reservoirs with good hydrodynamic connectivity between layers, as well as in fractured-porous systems. According to several studies, cyclic waterflooding is most efficient when reservoir oil viscosity ranges from 0.4 to 25.0 mPa·s. Particularly favorable conditions for unsteady processes occur in reservoirs containing gassaturated, low-viscosity oils, as such systems exhibit high fluid mobility and increased sensitivity to changes in flow regime. These observations highlight the need for an individual approach to designing UW technologies, taking into account reservoir and fluid properties, and confirm the prospects for further research in this area. Hydrodynamic simulations have shown that this approach is especially effective for heterogeneous reservoirs with a wide range of permeabilities. The authors note that the technology’s efficiency largely epends on the proper selection of operational parameters—cycle amplitude and frequency—which requires consideration of complex reservoir structure, fluid saturation, and filtration characteristics. In particular, for reservoirs characterized by three-phase systems (oil, water, gas) with high-permeability flow channels, optimizing cycle frequencies becomes more challenging. Special attention is given to the applicability of the technology at high water cuts (up to 98% and above), which are typical of the late stages of field development. Keywords: oil recovery, hard-to-recover reserves, cyclic injection, oil reservoir, injection amplitude, cycle frequency. 83-91 Publication history Article received: 07.10.2025 Article accepted: 04.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-83 84 VOLUME 31 (07) ISSUE 07 2025 Introduction Among contemporary enhanced oil recovery (EOR) methods, cyclic waterflooding holds a distinct position due to its high efficiency, broad applicability, and relative simplicity of implementation. In contrast to many other techniques that require complex equipment or are constrained by narrow operating conditions, cyclic (periodic) waterflooding can be effectively applied across a wide range of geological and thermobaric settings, which makes it a highly practical solution in oilfield development. Extensive research and field experience have demonstrated that alternating injection and production cycles not only stimulate oil recovery but also reduce water cut in the produced fluids. This effect is attributed to the cyclic influence on heterogeneous reservoir systems, which initiates a redistribution of flow: water from high-permeability zones is partially diverted into lowerpermeability regions, thereby improving sweep efficiency. This technology is particularly significant in the development of multilayered and geologically complex reservoirs, where the selection of an optimal development strategy must take into account detailed hydrodynamic interactions between layers as well as the internal heterogeneity of productive horizons. Consequently, cyclic waterflooding represents not only an economically viable but also a scientifically substantiated approach to enhancing the efficiency of developing hard-to-recover hydrocarbon reserves. Analysis of Studies The investigation of oil recovery characteristics from a productive reservoir under combined unsteady waterflooding and periodic production (UW+PP) was carried out using numerical simulation of three-phase flow processes. A mathematical model was employed that accounts for the simultaneous movement of oil, water, and gas, with the capability of defining variable boundary conditions reflecting the cyclic nature of the process [1,4]. This approach enables a more comprehensive representation of phase flow dynamics, the impact of reservoir heterogeneity, and interlayer hydrodynamic communication on hydrocarbon recovery efficiency when applying the UW+PP technology. As a computational model of a heterogeneous reservoir, formation “A” was considered, represented by a three-layer system characterized by interlayer permeability variations. All three layers are hydrodynamically connected and have approximately equal thickness. The middle layer is highly permeable, with permeability fixed at Khp=2,0 µm², serving as the primary fluid conduit. The upper and lower layers are represented by low-permeability intervals, with permeability coefficients ranging from 0,001 to 0,1 µm² depending on the specific task conditions. Such a model adequately reproduces filtration conditions in heterogeneous reservoirs and provides an assessment of the effectiveness of unsteady water-flooding technology, taking into account flow redistribution between zones with varying filtration capacities. It is assumed that once the water cut of the produced fluids reaches 95%, the reservoir development system is switched to an unsteady (cyclic) operating mode. Within this regime, alternating periods of injection and production are implemented as follows: • at the first stage, injection wells are shut in for 10 days, while production wells remain in operation; • after this period, water injection is resumed, whereas production is suspended for 10 days. VOLUME 31 (07) ISSUE 07 2025 85 This cycle of periodic influence continues until the water cut of the produced fluids reaches 98%, at which point operation of all wells in the considered reservoir section is completely terminated. Such a scheme makes it possible to model the effect of alternating injection and production phases on flow redistribution in a heterogeneous reservoir, as well as on the ultimate oil recovery. Figure 1: Reservoir performance under different operating regimes: (a) oil rate profile; (b) water cut profile. Comparison of the base case with unsteady waterflooding with periodic shut-ins (permeability of low-permeability layers assumed to be ~10 mD). Similar approaches are applied at several oil fields where conventional waterflooding methods prove ineffective due to high reservoir heterogeneity. Positive results of implementing cyclic operating modes under conditions of highly waterflooded reservoirs have been reported in the literature [2,3,6], confirming the potential of the proposed scheme. To evaluate the impact of reservoir filtration-capacity properties on the efficiency of heterogeneous reservoir development, a series of numerical experiments was conducted. In the simulation model, the permeability of the highly permeable middle layer was fixed at k ~2000 mD. The permeability values for the low-permeability upper and lower layers were varied and sequentially assigned as 100 mD, 50 mD, 10 mD, and 1 mD, which enabled analysis of system behavior over a wide range of permeability contrasts (Fig. 2). The initial (“starting”) water cut of the produced fluids was assumed to be 95%. For each permeability scenario, two development regimes were simulated: • Base case, in which all wells operate under a steady-state regime (continuous injection and production); • Alternative case, implementing unsteady waterflooding with periodic water injection and counter-phase fluid production (UW+PP). A comparative analysis of the results allowed assessment of the impact of cyclic operation on flow redistribution within the heterogeneous reservoir and on the efficiency of involving lowpermeability zones in production. Analysis of the graphs in Fig. 1 indicates a positive effect of the UW+PP technology: compared to the base case, there is a noticeable increase in current oil rates and a reduction in water cut. This suggests more effective engagement of low-permeability zones due to redistribution of the 86 VOLUME 31 (07) ISSUE 07 2025 displacing agent. At the same time, it should be noted that under the cyclic regime, production wells experience downtime periods, which may potentially slow the cumulative oil recovery rate during long-term reservoir operation [5,9]. Figure 2: Relative changes in oil rate (a) and absolute changes in water cut (b) under unsteady waterflooding with periodic production (UW+PP) for a reservoir with layered permeability heterogeneity. Fig. 2 presents changes in current operational performance induced by the implementation of unsteady waterflooding with periodic shut-ins (UW+PP) at the studied reservoir section for different low-permeability layer values. For clarity, data points corresponding to temporary production well shutdowns are excluded from the graph. It should be noted that the analysis is based on relative oil rates, i.e., deviations from the base case expressed as fractions of its value. α – current oil rate of the studied reservoir section. Fig. 3 shows the dynamics of relative cumulative oil recovery increase (expressed as fractions of the base case) resulting from the application of the considered technology for different lowpermeability layer values. The analysis indicates that the maximum oil increment—27.5%—is achieved at the lowest permeability of the low-permeability intervals, whereas at the highest permeability, the increment is only 1.4%. This demonstrates the increased efficiency of the technology under conditions of pronounced reservoir heterogeneity [7]. VOLUME 31 (07) ISSUE 07 2025 87 Figure 3: Dynamics of relative cumulative oil (a) and fluid (b) production under unsteady waterflooding combined with counter-phase periodic operation of production wells, depending on the permeability of low-permeability layers. The same figure also presents relative changes in cumulative fluid production compared to the base scenario. Implementation of the UW+PP technology is accompanied by a significant reduction in total fluid production—ranging from 5% to 14% depending on the permeability of the low-permeability layers. This reflects more selective development of productive intervals and a reduction of excessive water inflow, which positively impacts overall reservoir development efficiency. Table 1 presents the results of model calculations of key operational indicators for different development scenarios of an oil reservoir with a layered, permeability-heterogeneous formation under unsteady waterflooding combined with periodic production of wells (UW+PP). The data allow evaluation of the effectiveness of the considered technology under reservoir heterogeneity and provide a comparison with base-case development scenarios. Table 1. Results of numerical simulations. Permeability of the lowpermeability interlayer, mD Permeability ratio of the layers Oil recovery factor (ORF) Incremental oil recovery factor (IORF) base UW 100 20 0,623 0,688 0,045 50 40 0,601 0,654 0,053 10 200 0,536 0,614 0,079 1 2000 0,346 0,589 0,242 Conclusion The application of unsteady waterflooding combined with periodic production of wells (UW+PP) in reservoirs with a high degree of layered permeability heterogeneity demonstrates a significant increase in oil recovery. The positive effect is observed at the early stages of technology implementation, making it particularly effective for accelerated reservoir depletion. 88 VOLUME 31 (07) ISSUE 07 2025 An additional advantage is a substantial reduction in produced water volumes, which contributes to higher technological and economic efficiency of reservoir development. Even in relatively homogeneous, high-permeability reservoirs, the technology reduces total fluid production by approximately 5%, although the corresponding increase in oil recovery is less pronounced— around 1.3%. Thus, the UW+PP technology can be considered an effective tool for enhancing development efficiency both in strongly heterogeneous reservoirs and in more homogeneous formations, where its main benefit lies in reducing water cut. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES 1. Abzalov R. E., Malyshev V. L., Mavrin S. A. (2020) «Analiz effektivnosti nestatsionarnogo zavodneniya v posloyno neodnorodnykh plastakh». Molodoy uchonyy, № 14 (304), aprel 2020, s. 123–126 2. Yermukhametov V. L. (2020) «Nestatsionarnoye zavodneniye v rezhime obrazovaniya iskusstvennoy treshchinovatosti». Molodoy uchoniy, № 45 (335), November 2020, pp. 15– 17. 3. Veliyev, E. M. Issledovaniye zavisimosti effektivnosti tekhnologii nestatsionarnogo zavodneniya ot prodolzhitel'nosti poluperioda raboty/prostoya nagnetatel'nykh skvazhin v tsikle pri razrabotke vysokoproduktivnykh neodnorodnykh kollektorov malovyazkoy nefti / E. M. Veliyev // Problemy sbora, podgotovki i transporta nefti i nefteproduktov / IPTER. – Ufa, 2015. – Vol. 2 (100). – pp. 46-56. VOLUME 31 (07) ISSUE 07 2025 95 Economic risk is determined by the corresponding type of activity. Signs of economic activity include: • belonging of the subject to General useful, economic practice (in our case, the enterprise); • the fact of the existence of a subject of activity, confirmed by an act of state registration (as a legal entity; • the sphere of implementation in the field of economics as a sphere of economic activity; • the presence of operational goals, expressed, on the one hand, in meeting the needs of society, its members and employees of the company, and on the other, in the creation of material and intangible benefits; • income serves the purpose of covering material costs and various types of expenses incurred by the enterprise. Economic risks and uncertainty are closely related. Under this category of threats, we will understand the likelihood of unpleasant events as a result of a business decision made by the company's management. It is suggested that the positive side of the risk should not be taken into account for the time being. The uncertainty of the economic environment is, in fact, the main reason for the event that may occur in the future [8]. But in addition to uncertainty, there is a need to work in all areas (financial, material, information, time resources, etc.).) resource limitation affects economic risk. The danger arises as a result of a certain objective probability of unpleasant events, and the decision made forms subjective prerequisites for them. In general, in economic relations, the subjective and objective aspects of any economic facts and phenomena play one of the main roles. And the subject of the relationship always makes an evaluative judgment about any probable event in its dynamics. And since these relationships themselves involve at least two subjects, we must understand which of them is considered a risk. To do this, it is proposed to pay attention to the diagram presented below. Scheme of internal and external economic relations between business entities [9]. The enterprise itself is a subject of economic relations (ER), but its owners and employees simultaneously act as subjects of legal relations, Labor Relations and, naturally, ER. Thus, the subjects of ER relate to the objects of ER existing in them. As objects of such relations, we mean the totality of property and non-property rights and obligations arising for the relevant subjects. All this works both within the enterprise and in relation to subjects outside it. Foreign ERS are directly related to such facts and phenomena that are formed in complex entrepreneurial practice related to making a profit. However, if economic activity is associated not only with it, then the associated risk is much broader than the dangers of an entrepreneurial nature. Risks of a dual nature (entrepreneurial and other types) are included in the broader concept of economic risk, for example [9-10]: • financial risk; • property riski; • resource risk, etc. And what relationships in the company may not be related to entrepreneurial activity? For example, Labor Relations related to the social sphere of the enterprise's life: for housing and communal services that are on the balance sheet, if the enterprise is a city-maker or with employees working in a house of Culture, a recreation center, etc. The next example that we can 96 VOLUME 31 (07) ISSUE 07 2025 name is charitable activities. It is the movement of financial resources, the acquisition of property and Information, time, materials, etc. related to the use of other resources such as. The list of such business practices can be continued. Figure 1: The place of economic risk in the field of probabilities. The division of risks associated with economic relations and entrepreneurship into the following types Figure 2: Classification of economic risks in the logic of "diversification" according to three internal characteristics. The diagram above shows the classification of economic risks in the logic of "diversification" according to three internal characteristics: • by the relationship of risk with relations of an economic or non-economic nature; • with the inclusion of entrepreneurial focus in the risk associated with economic activity; VOLUME 31 (07) ISSUE 07 2025 97 • types of entrepreneurial risk as the main form of economic risk. Indeed, relations between subjects are not only economic in nature. They are related to politics, technology, international relations, etc. can be identified with. At the same time, the types of economic risks, in addition to the purely business context, can include specific types of universal risks. These include threats that can have consequences not only in terms of profit, but also for business initiatives. For example, damage to the finances of employees can occur due to errors in calculating the income tax of individuals or the Social Insurance Fund (financial risk). Negative consequences (property risk) are also possible for property on its balance sheet in the social sphere of the enterprise. The concept of risk in the field of economic activity therefore has fundamental differences from other types: entrepreneurial, financial, investment, etc. All these forms are included in the systemic phenomenon of economic risk, and some in the concept of entrepreneurial risk. This happens when they are not intended to be of a different nature than when it comes to making a profit. Thus, investment risk is essentially a type of entrepreneurship, based on the definition of investment activity. The same can be said about credit risk, but financial risk, as we saw earlier, is somewhat broader. We define financial risk as a type of economic risk that determines the likelihood and consequences of an unpleasant event in the form of loss of financial resources (money) as a result of a decision made. In general, the possible consequences of risk for the company's economy are formed in three main directions. 1. Failure to obtain the planned benefit in whole or in part (profit, Income, staff satisfaction, business capitalization, etc.). 2. Use the resources of the company (money, personnel, property, information, etc.).) complete or partial loss. 3. Additional financial and material costs (for example, in case of compensation for losses incurred). We have essentially considered the probable consequences of threats to the economic complex of the enterprise. It seems that the goal of delimiting various threats associated with the activities of a business entity has been achieved. This means that the risk Manager, Project Manager or investment economist can better manage the basic concepts of risk management based on the result obtained in the article. At the same time, the model of the subject area of the professional sphere is enriched with clarity regarding their important distinguishing features. The result Recently, more and more attention has been paid to the field of research of all types of economic risks. This is confirmed by an increase in the volume of literature devoted to the topic, and most importantly, a noticeable progress in the quality of the proposed measures. Moreover, the experience of foreign and Russian companies shows that firms pay more and more attention and resources to this area, special departments are organized for analysis, Control and Risk Reduction, and an increasingly advanced decision-making methodology is being introduced to reduce the negative consequences of risks. Bir daha qeyd etmək lazımdır ki, risk sahibkarlıq fəaliyyətinin və ümumilikdə iqtisadi fəaliyyətin tərkib hissəsidir. If the activity is not accompanied by risk, it is most likely not a market activity. There is no profit without Risk, and profit is the goal of any economic activity. Therefore, 98 VOLUME 31 (07) ISSUE 07 2025 appropriate knowledge of risk, its causes, structural features and management methods increases the effectiveness of entrepreneurial activity. There are many methods of managing risk. A qualified and trained specialist must identify risks, analyze them, filter out the harmless, and then make a decision to reduce the negative consequences of risk. If the most rational set of actions is selected, the risk is reduced to its elimination. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCE 1. Bikov А. А. On the relationship between the concepts of "risk" and "uncertainty" // Problems of risk analysis. 2014. № 1. С. 4-5. 2. Gorlatov А.S., Liman I.А. The economic category "risk": the essence and methods of regulation [Electronic resource] - URL:httpsV/cyberleninka.ru/article/n/ekonomicheskayakategoriya-risk-suschnost-i-metody-regulirovaniya (дата обращения: 21.06.2021). 3. Kantor О.G. Classification of methods of quantitative assessment of economic risk [Electronic resource] – URL:https://cyberleninka.ru/article/nMassffikatsiya-metodovkolichestvennoy-otsenki-ekonomicheskogo-riska (date of request: 20.06.2021). 4. Kunitsina, N.N. Economic dynamics and risks / Kunitsina, N.N. – М.: Economics of agricultural and processing enterprises, 2002. – 288 p. 5. Blank, I.А. Financial risk management / Blank, I.А. – К.: Nika Center, 2005. – 600 p. 6. Kuznetsova, N.V. Risk management / Kuznetsova, N.V. – Vladivostok: Far Eastern University Press, 2004. – 168 p. VOLUME 31 (07) ISSUE 07 2025 99 7. Hohlov, N.V. Risk management: a textbook for universities / Hohlov, N.V. – М.: UNITYDANA, 2001. – 239 p. 8. Nazarova, I.G. Risk management in business: a textbook / Nazarova, I.G. – Ukhta: УГТУ, 2003. – 136 p. 9. Shapkin, А.S. Risk theory and modeling of risky situations: textbook / Shapkin, А.S., V.А. Shapkin. – М.: Dashkov and Co., 2005. – 880 p. 10. Blank, I.A. Financial risk management / I.A. Blank. – К.: Nika Center, 2005. – 600 p. MÜASİR CƏMİYYƏTDƏ İQTİSADİ RİSKLƏR Məhəmməd Şirinov1, Vadim Boqopolskiy2, Azad Bağırov3 1Müəllim, Azərbaycan Dövlət Neft və Sənaye Universiteti. E-mail: [email protected]u 2,3 Dosent, Azərbaycan Dövlət Neft və Sənaye Universiteti, E-mail:, vadim46.[email protected]2, azad[email protected]3 XÜLASƏ Məqalə iqtisadi təhlükəsizlik sisteminin mühüm komponenti kimi risk təhlilinin nəzəri və metodoloji aspektlərinə həsr edilmişdir. Məqalədə risk anlayışı, risk növləri və onların qiymətləndirilməsi üsulları haqqında məlumatlar ümumiləşdirilmişdir. Bundan əlavə iqtisadi risklərin əsas növlərinin biznesə və bütövlükdə iqtisadiyyata təsirini nəzərdən keçirəcəyik, həmçinin nümunələr və statistika təqdim edəcəyik. İqtisadi sistemlərin növləri və müvafiq risklərin xüsusiyyətləri məsələsinin yeni müəllif şərhi təqdim olunur. Riskin qiymətləndirilməsi üçün elmi metodologiyanın makro səviyyədə tətbiq edilməsinin məqsədəuyğunluğu barədə nəticə çıxarılır. Açar sözlər: iqtisadi risklər, iqtisadi sistemlər, iqtisadi təhlükəsizlik, risklərin qiymətləndirilməsi, risklərin idarə edilməsi. ЭКОНОМИЧЕСКИЕ РИСКИ В СОВРЕМЕННОМ ОБЩЕСТВЕ Магомед Ширинов1 , Вадим Богопольский2, Азад Багиров3 1Преподаватель, Азербайджанский Государственный Университет Нефти и Промышленности. E-mail: [email protected] 2,3Доцент, Азербайджанский Государственный Университет Нефти и Промышленности. E-mail: [email protected] , [email protected] РЕЗЮМЕ Статья посвящена теоретико-методологическим аспектам анализа рисков как важного компонента системы обеспечения экономической безопасности. В статье обобщена информация о понятии риска, о видах рисков и методах их оценки. Кроме того, мы рассмотрим влияние основных видов экономических рисков на бизнес и экономику в целом, а также приведем примеры и статистику. Представлена новая 100 VOLUME 31 (07) ISSUE 07 2025 авторская интерпретация вопроса о видах экономических систем и специфике соответствующих рисков. Сделан вывод о целесообразности использования научной методологии оценки рисков применительно к макроуровню. Ключевые слова: экономические риски, экономические системы, экономическая безопасность, оценка риска, управление рисками. VOLUME 31 (07) ISSUE 07 2025 101 RESEARCH UNIVERSAL COMBINED INHIBITOR FOR THE OIL AND GAS INDUSTRY Mehpara Adygezalova Doctor of Technical Sciences, Associate Professor of the Department of Chemistry and Technology of Inorganic Substances, Azerbaijan State University of Oil and Industry. E-mail: [email protected] ABSTRACT The inhibiting efficiency of a multifunctional combined inhibitor against hydrogen sulfide and carbon dioxide corrosion of St3 carbon steel was investigated using the gravimetric method in model formation water MI. Corrosion tests were carried out in sealed vessels with a volume of 0.5 L using flat steel specimens (St3) with dimensions of 30 × 20 × 1 mm. A combination of gossypol resin and MARZA was used as the multifunctional inhibitor, with diesel fuel and kerosene serving as solvents. It was established that when kerosene is used as the solvent, the protective efficiency of the inhibitor varies in the range of 75–96 %, while with diesel fuel it reaches 80–100 %. The study demonstrated that the use of the combined inhibitor in MI water containing hydrogen sulfide and carbon dioxide ensures a corrosion rate of approximately 0.04 g/m²·h during 24-hour tests at an inhibitor concentration of no less than 70 mg/L. With increased exposure time, a similar level of corrosion resistance can be achieved at a lower inhibitor concentration of 50 mg/L. A comparable trend was observed both in carbon dioxide and in hydrogen sulfide–carbon dioxide environments. Keywords: imitation, hydrogen sulfide, carbon dioxide, polarization resistance, electrochemical impedance spectroscopy, steel ductility, solid-phase diffusion, inhibition, hydrogen. Introduction The corrosion damage of oilfield equipment is determined by the physicochemical properties of the aqueous and hydrocarbon components of the system, their composition, quantitative ratio, and the presence of dissolved gases such as hydrogen sulfide, carbon dioxide, oxygen, and others. At high flow velocities, which ensure intensive mixing of phases, emulsion systems of the oil-inwater or water-in-oil type are formed. Upon settling, these systems separate into two immiscible phases. In all cases, however, water is the primary corrosive medium [1–2]. The most common and critical types of corrosion currently affecting the oil industry are carbon dioxide corrosion, hydrogen sulfide corrosion, microbiologically influenced corrosion (MIC), and hydrogen embrittlement, among others [1–4]. A significant portion of metallic corrosion damage in both natural and industrial environments is the result of biological corrosion. The danger of bacterial corrosion lies in the ability of bacteria to 101-109 Publication history Article received: 08.10.2025 Article accepted: 05.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-101 102 VOLUME 31 (07) ISSUE 07 2025 rapidly reproduce and easily adapt to changing physical, chemical, and biological environmental conditions. Among these microorganisms, sulfate-reducing bacteria (SRB) are the most aggressive toward metal structures. SRB act as producers of corrosive agents, primarily hydrogen sulfide. The reaction of hydrogen sulfide with metal results in the formation of iron sulfide, which accumulates on the inner surfaces of pipelines and other equipment [5]. The intensive growth of sulfate-reducing bacteria (SRB) leads to a sharp increase in the corrosion rate — by approximately 24 times. The presence of stagnant zones further enhances the activity of SRB, resulting in a significant increase in localized corrosion rates. Microbiologically influenced corrosion (MIC) causes enormous economic damage to national industries. Its impact is particularly severe in the oil production and refining sectors. According to expert assessments, the vast majority of corrosion failures in oilfield equipment are associated with microbiological factors. This problem remains highly relevant and has not yet been fully resolved. One of the most effective methods to combat this type of corrosion of structural materials is the use of corrosion inhibitors, particularly universal inhibitor formulations. The versatility of such inhibitors lies in their ability not only to reduce the overall corrosion rate and the severity of localized damage but also to act as efficient biocides, especially against sulfate-reducing bacteria. Even at low (molar-level) concentrations, these additives can effectively suppress both metal corrosion and hydrogen uptake, thereby preventing hydrogen embrittlement of equipment [6]. Brittle failure occurs instantaneously in hard and strong metals with limited plasticity when critical stress levels are reached. In contrast, soft and ductile steels begin to delaminate gradually. Once these local delaminations reach a certain size, they can merge to form large-volume cavities that lie either in a single plane or as stepped layers stacked upon one another. During delamination in soft steels, hydrogen bubbles, or "blisters," form near the surface at shallow depths. In [7], a theoretical evaluation of the destructive pressures exerted by hydrogen was conducted, with calculated values ranging between 150 and 200 kgf/sm². The authors of [9] performed a detailed study on the influence of carbon dioxide on hydrogen embrittlement and sulfide stress corrosion cracking (SSCC) in acidic environments at pH = 4.5, under varying partial pressures of hydrogen sulfide. A significant increase in hydrogen permeation into steel was observed when both H₂S and CO₂ were present simultaneously. The effect of carbon dioxide diminishes at high hydrogen sulfide concentrations. Thus, the literature analysis presented indicates that, despite the wide range of corrosion inhibitors available both domestically and internationally, the issue of protecting metallic equipment in gas and oil production remains highly relevant and unresolved. Experience in corrosion control demonstrates that the reliable operation of technological equipment can be ensured through the use of inhibitors [11]. Compared to other corrosion protection methods, inhibitor technologies for aggressive media are relatively simple and do not require significant material or technical expenditures. The addition of inhibitors in small concentrations to a corrosive environment reduces the corrosion rate or even practically suppresses the process altogether [12]. Despite significant progress in this field, many challenges remain unresolved, including issues related to the availability, cost, and environmental safety of additives. Intensive research on new inhibitors is ongoing and will continue [12,13]. VOLUME 31 (07) ISSUE 07 2025 103 One of the primary requirements for inhibitors is multifunctionality. They should not only reduce the overall corrosion rate but also slow down hydrogen uptake in environments containing hydrogen sulfide, carbon dioxide, and their combinations, thereby preserving the mechanical properties of metallic structural materials. Additionally, inhibitors should possess sufficient bactericidal activity and effective protection in two-phase aqueous hydrocarbon systems, which depends on favorable distribution coefficients of the additives. Currently, such studies are being conducted intensively, resulting in a wide range of inhibitors. However, data on the universality of their action remain extremely limited. The aim of the present work is to investigate the effect of a multifunctional combined inhibitor on the corrosion rate of steel in environments containing hydrogen sulfide, carbon dioxide, and their combination. Experimental Methodology Corrosion tests were conducted using St3 steel samples with the following chemical composition (wt.%): 0.2% C, 0.5% Mn, 0.15% Si, 0.04% P, 0.05% S, 0.3% Cr, 0.2% Ni, 0.2% Cu, and 98.36% Fe. Steel specimens measuring 30 × 20 × 1 mm were ground with abrasive papers of varying grit sizes until a bright, polished surface was obtained. Subsequently, the samples were thoroughly rinsed with water and acetone. After degreasing, all handling was performed using tweezers or filter paper to avoid contamination. To activate the surface, the samples were immersed for one minute in a 15% hydrochloric acid solution, then rinsed thoroughly with running and distilled water. The specimens were dried with filter paper, wrapped in it, stored in a desiccator with a moisture absorber for 24 hours, and weighed on an analytical balance with an accuracy of ±0.0001 g [14, 15]. Corrosion testing was performed gravimetrically [16] in a model formation water MI with the following composition (g/L): NaCl – 17, NaHCO₃ – 0.8, MgCl₂·6H₂O – 0.2, CaCl₂ – 0.2. Highly mineralized solutions were saturated separately and jointly with hydrogen sulfide and carbon dioxide gases. Carbon dioxide was supplied from a high-pressure cylinder to a pressure of 1 atm gauge. The pressure in the vessels was monitored manometrically. Hydrogen sulfide was generated in situ by adding stoichiometric amounts of sodium sulfide and hydrochloric acid to the background solution. The concentration of hydrogen sulfide was controlled by the iodometric back-titration method [17]. The corrosion rate was calculated using the formula: m KS   = (1) Where: Δm is the difference in sample mass before and after exposure, S is the surface area of the samples, τ is the exposure time. The inhibition efficiency coefficient was calculated as: 0 .инг K K  = (2) Where: K0 is the corrosion rate of the sample in the absence of inhibitor, Kinh is the corrosion rate of the sample in the presence of inhibitor (g/m²·h). 104 VOLUME 31 (07) ISSUE 07 2025 The inhibition efficiency (protection efficiency) of the inhibitor was calculated using the formula: 0 0100% KK ZK − = (3) where K0 and K are the corrosion rates in uninhibited and inhibited solutions, respectively. The corrosion permeability was calculated using the formula: 1,12Пк K= (4) In the laboratory study, MARZA and gossypol resin were investigated as inhibitors. The exact chemical composition of MARZA is not disclosed by the manufacturers; therefore, the experiments were conducted using only its conditional name. MARZA is an organic chemical compound whose molecular structure includes atoms of carbon, hydrogen, oxygen, and others. The molecule of MARZA contains a triple covalent bond. Gossypol resin is a plant-derived inhibitor. It is obtained as an intermediate product during the production of cottonseed oil [18]. Gossypol resin varies in color from light brown to black and has a characteristic odor. It solidifies at 50 K and melts at 435 K. The resin contains 10–12% nitrogenous compounds and has a density of 0.8600 kg/m³. It has a molecular weight of 290–300 and is poorly soluble in water but readily soluble in hydrocarbons. To reduce the freezing point, diesel fuel and kerosene were used as solvents. The experimental results are presented in Table 3 [18]. Table 3. Freezing point of gossypol resin at various concentrations. ;№ Solvent Ratio of reagent to solvent Freezing point, °C 11 Diesel fuel 1:1 -14 1:2 -16 1:3 -18 22 Kerosene 1:1 -15 1:2 -18 1:3 -25 As shown in the table, increasing the amount of solvent reduces the freezing point of the gossypol resin. The best effect was achieved at a reagent-to-kerosene solvent ratio of 1:3. Results and Discussion The introduction of the combined inhibitor into the test solutions consistently resulted in a decrease in corrosion rate and an increase in protective efficiency with increasing inhibitor concentration. With longer experiment durations, the corrosion rate decreased in both inhibited and uninhibited solutions, which is consistent with observations reported in [19–24]. In the latter case, this phenomenon indicates the protective action of corrosion product films forming on the electrode surface, which shield the metal substrate. The most significant reduction in corrosion rate in environments containing either hydrogen sulfide or carbon dioxide was observed during the first hour after the experiment began. It is VOLUME 31 (07) ISSUE 07 2025 111 production, mediumand low-temperature ones are mainly employed for building heating, greenhouse cultivation, and industrial processes. The world’s first geothermal power plant was commissioned in Italy in 1904, marking the start of technological progress from high-enthalpy steam systems to modern binary-cycle units capable of operating at moderate temperatures. By 2020, global installed capacity exceeded 15.95 GWe, though growth has slowed since 2005 due to competition from other renewables, regulatory delays, and bureaucratic barriers [1]. Globally, an estimated 20–30 million oil and gas wells have been abandoned, offering substantial potential for geothermal repurposing. Utilizing abandoned oil and gas wells (AOGWs) can reduce drilling costs by about 50%, as the subsurface data, casing, cement, and tubing are already available. These factors make AOGW conversion an economically and environmentally sound approach for geothermal deployment [2]. Geothermal extraction can rely on downhole heat exchanger systems (DHES), commonly designed as openor closed-loop configurations. Open-loop systems circulate formation fluid between production and reinjection wells, whereas closed-loop designs use sealed pipe networks that avoid contact with the reservoir and mitigate corrosion or scaling. Closed-loop DHESs, typically U-tube or coaxial, are optimized by parameters such as pipe geometry, insulation, and fluid properties [3]. Reservoir temperatures of 150–250 °C indicate significant geothermal potential in AOGWs. For lower-temperature basins (120–130 °C), electricity generation through a single-flash geothermal cycle integrated with a closed-loop DHES is feasible. The present study develops a thermodynamic model to evaluate such systems, performing sensitivity analyses on reservoir and design parameters, geothermal gradient, and insulation performance. The model aims to deliver a preliminary technical feasibility assessment for future investment decisions [4, 5]. Description of the Proposed System The system presented in this study consists of two main components, as illustrated in Figure 1. The right section of the figure represents the Downhole Heat Exchanger (DHX), which enables direct extraction of heat from subsurface rock formations. The other part corresponds to the conversion unit, where the recovered thermal energy is transformed into electricity. A coaxial heat exchanger configuration was selected due to its lower pressure losses and higher heat-transfer efficiency compared to other designs. To enhance heat extraction, a counter-flow arrangement is applied for the circulating fluid within the DHX. In this setup, the cold working fluid enters through the annular pipe, gains heat while descending, and exits as a heated stream through the inner pipe. To minimize thermal losses during circulation, the inner pipe is insulated with glass wool, maintaining temperature stability throughout the cycle. 112 VOLUME 31 (07) ISSUE 07 2025 Figure 1: Schematic representation of geothermal energy extraction from an abandoned well (AOGW). The diagram illustrates the operating principle of a geothermal power generation system. Hot fluid and steam extracted from the subsurface are first separated by a separator, after which the steam is directed to a turbine, converting thermal energy into mechanical work. The turbine drives an electric generator, producing electricity. The exhaust steam is then cooled and condensed in a condenser, and the resulting liquid is pumped back into the geothermal well under pressure. This closed-loop process ensures continuous heat exchange between the hot and cold streams, allowing subsurface thermal energy to be converted into sustainable, environmentally friendly electricity. Global developments in this area In the global transition from fossil fuels to clean and renewable energy sources, the reuse of abandoned oil and gas wells (AOGWs) for geothermal power generation is attracting growing attention. Millions of inactive wells worldwide intersect geological formations with high thermal potential, offering opportunities for efficient resource utilization and reduced carbon emissions. Currently, the United States has approximately 3.7 million abandoned wells, while India has around 13,000, with an estimated geothermal potential of 10,000 MW. Globally, the potential is assessed at several hundred thousand megawatts. Reusing a fraction of these wells could enable new energy generation while significantly lowering operational costs [6]. Modeling studies at the Forest Reserve field in Trinidad indicate that a small system composed of several wells could produce 3–4 MW of electricity over a 25-year period. Similarly, pilot tests in Colorado and Texas (USA) have demonstrated the feasibility of integrating abandoned wells into local heating and power networks. These findings confirm the technical and economic viability of such projects in the long term. Technically, this approach mitigates one of the main challenges of conventional geothermal projects—drilling costs—by utilizing existing well infrastructure and pre-characterized geological and hydrodynamic data. Furthermore, it minimizes land disturbance and environmental risks [7]. Two primary types of heat-exchange systems are applied for geothermal energy recovery: openloop and closed-loop configurations. In open-loop systems, fluid is extracted from the reservoir and reinjected after cooling, which may lead to corrosion and scaling issues. In closed-loop systems, heat is transferred through a sealed piping network without direct contact between the VOLUME 31 (07) ISSUE 07 2025 113 working fluid and the formation, making it safer and more suitable for repurposed wells. Power generation typically employs the Organic Rankine Cycle (ORC), which uses low-boiling working fluids and is well-suited for lowand medium-temperature resources (80–150 °C). Factors such as drilling depth, rock thermal conductivity, well length, and insulation thickness have a direct impact on overall system efficiency [9]. Economically, this technology offers notable advantages. Because no new drilling is required, initial capital expenditures can be reduced by 40–60%, and pilot studies show payback periods of 5–7 years under favorable conditions. The reduced cost of well abandonment further enhances project attractiveness. However, several technical and regulatory challenges remain. Degraded casing and cement integrity in old wells may cause leakage during heat circulation, necessitating additional technical remediation. Moreover, in many countries, regulatory frameworks for geothermal reuse of abandoned wells are still underdeveloped. In summary, the utilization of AOGWs for geothermal energy is technically feasible, economically viable, and environmentally beneficial. This approach supports energy decarbonization and promotes resource efficiency through infrastructure reuse. In the near future, widespread deployment of this technology could enable the reintegration of thousands of inactive wells into the global energy system [10]. Conclusion The findings of this study demonstrate that repurposing abandoned oil and gas wells for geothermal energy generation holds substantial potential for the sustainable development of the energy sector. This approach eliminates the need for new drilling, reduces project costs, and leverages existing geological and production data to minimize technical risks. Closed-loop downhole heat-exchange systems are identified as the most efficient option for such wells, offering high thermal performance with minimal corrosion and scaling. Modeling results suggest that reservoirs within the 120–130 °C range can produce 3–5 MW of electricity. A potential 50% reduction in drilling costs improves project economics, shortening payback periods to 5–7 years. Optimizing insulation and well design significantly enhances system performance, though issues related to casing integrity and cement degradation may increase leakage risks. In addition, the absence of comprehensive regulatory frameworks and complex licensing procedures remain key barriers to large-scale implementation. Nevertheless, pilot projects in the USA, China, Canada, and Trinidad have confirmed the practical potential of this technology. Overall, geothermal energy recovery from abandoned wells is a strategically important, economically sound, and environmentally responsible pathway for advancing the global energy transition. Future research should focus on improving heat-transfer modeling, testing new insulation materials, and evaluating long-term operational reliability. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments 114 VOLUME 31 (07) ISSUE 07 2025 The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES 1. Ashena, R. (2022). Retrofitting Abandoned Petroleum Wells for Geothermal Energy Production – Overview Analysis of Some Case Studies and Introduction of an Innovative Idea. SSRN. 2. Li, J., Wang, H., Wang, T., Li, H., Guo, C., & Yang, D. (2025). Feasibility Analysis of Converting Abandoned Oil and Gas Wells into Geothermal Wells and Power Generation. SSRN. 3. Jello, J., & Baser, T. (2022). Repurposing Abandoned Oil and Gas Wells for Geothermal Applications. Energy Proceedings, 25. 4. Usuolori, B. O., Izuwa, N. C., Kerunwa, A., & Nwogu, N. C. (2025). A Study of Geothermal Energy Prospect from Abandoned Oil and Gas Wells in Nigeria. IOGR. 5. Li, X., et al. (2023). Life Cycle Assessment of Repurposing Abandoned Onshore Oil and Gas Wells for Geothermal Energy. Journal of Cleaner Production. 6. Energy Technologies Office (U.S. Department of Energy). (2024). Wells of Opportunity: Geothermal Production from Hydrocarbon Wells. 7. “Reuse of Abandoned Oil and Gas Wells for Geothermal Energy Production.” (2017). Renewable Energy. 8. “Geothermal Energy Extraction from Abandoned Oil and Gas Wells: Techno-Economic and Policy Review.” (2023). Wiley Energy Reports. 9. “Potential for Heat Production by Retrofitting Abandoned Gas Wells into Geothermal Systems.” (2019). PLoS ONE. 10. “Reuse of Oil Wells in Geothermal District Heating Networks.” (2022). Energies, 17(1), 169. ВОССТАНОВЛЕНИЕ ГЕОТЕРМАЛЬНОЙ ЭНЕРГИИ ИЗ ЗАБРОШЕННЫХ НЕФТЯНЫХ И ГАЗОВЫХ СКВАЖИН: КОМПЛЕКСНАЯ ОЦЕНКА ПОТЕНЦИАЛА И ВОЗМОЖНЫХ ПРИМЕНЕНИЙ VOLUME 31 (07) ISSUE 07 2025 115 Абусалам Мухтаров Азербайджанский государственный университет нефти и промышленности, Кафедра энергетических технологий, Факультет энергетических технологий, аспирант, Баку, Азербайджан, muk[email protected]m РЕЗЮМЕ Ликвидированные нефтяные и газовые скважины могут быть повторно использованы для извлечения геотермальной энергии, представляя собой перспективную и устойчивую стратегию использования тепла недр при минимальном воздействии на окружающую среду. Скважины, расположенные в термально благоприятных геологических структурах, обеспечивают возможность преобразования тепловой энергии недр в электричество или прямое тепловое использование для промышленных, жилых и сельскохозяйственных нужд. Настоящее исследование представляет собой концептуальную оценку извлечения геотермальной энергии с использованием подземных теплообменных систем, эффективно функционирующих при средних температурах и низких расходах жидкости. В рамках исследования была разработана комплексная модель для оценки работы типовой скважинной системы в различных геологических и эксплуатационных условиях. Анализ учитывал влияние термических свойств пород, изменения температуры с глубиной, конструкции теплообменника и параметров теплоизоляции на эффективность теплопередачи. Кроме того, проводилась оценка долговременного поведения системы для определения устойчивости и потенциальной выработки энергии в течение всего эксплуатационного периода. Результаты показывают, что эффективность извлечения геотермальной энергии из ликвидированных скважин в первую очередь определяется распределением температуры в недрах, конструкцией и длиной теплообменной системы, а также тепловыми свойствами окружающих пород. Исследование демонстрирует, что правильно спроектированные подземные системы могут стать надежным и экологически безопасным источником возобновляемой энергии. Результаты подчеркивают потенциал повторного использования существующей скважинной инфраструктуры для диверсификации энергетического баланса, снижения зависимости от ископаемого топлива и поддержки перехода к низкоуглеродным энергетическим системам. Ключевые слова: Геотермальная энергия, Ликвидированные скважины, bосстановление тепла, Тепло недр, bозобновляемая энергия, yстойчивое развитие. LƏĞV EDİLMİŞ NEFT VƏ QAZ QUYULARINDAN GEOTERMAL ENERJİNİN ƏLDƏ OLUNMASI: POTENSİALIN VƏ TƏTBİQ SAHƏLƏRİNİN İNTEQRASİYALI QİYMƏTLƏNDİRİLMƏSİ Əbusalam Muxtarov Azərbaycan Dövlət Neft və Sənaye Universiteti, Energetika Fakültəsi, Enerji İstehsalı Texnologiyaları Fakültəsi, Baku, Azərbaycan, PhD tələbəsi, [email protected] XÜLASƏ 116 VOLUME 31 (07) ISSUE 07 2025 Ləğv edilmiş neft və qaz quyularının geotermal enerji çıxarılması üçün təkrar istifadəsi yeraltı istiliyi mənimsəmək üçün perspektivli və dayanıqlı strategiya təqdim edir, eyni zamanda ətraf mühitə təsiri minimuma endirir. Termal cəhətdən əlverişli geoloji strukturlarda yerləşən bu quyular yeraltı istilik enerjisini elektrik enerjisinə və ya birbaşa istilik istifadəsinə çevirərək sənaye, yaşayış və kənd təsərrüfatı sahələrində tətbiq etməyə imkan yaradır. Bu tədqiqat, orta temperatur və aşağı axın şəraitində səmərəli işləyə bilən yeraltı istilik mübadilə sistemləri vasitəsilə geotermal enerji bərpasının konseptual qiymətləndirilməsini təqdim edir. Əlavə olaraq, dünya üzrə ləğv edilmiş neft və qaz quyularından geotermal enerji əldə olunması ilə bağlı aparılan tətqiqatların nəticələrinin sistemli təhlilinə və məsləhət görülən tətbiqlərin qiymətləndirilməsinə bu məqalədə diqqət ayrılır. Tədqiqat çərçivəsində müxtəlif geoloji və əməliyyat şəraitində nümunəvi bir quyu sisteminin performansını qiymətləndirmək üçün əhatəli modelləşdirmə yanaşması hazırlanmışdır. Analiz zamanı süxur materiallarının istilik xüsusiyyətləri, dərinlik üzrə temperatur dəyişiklikləri, mübadilə sisteminin quruluşu və izolyasiya parametrlərinin istilik ötürmə səmərəliliyinə təsiri nəzərdən keçirilmişdir. Bundan əlavə, sistemin uzunmüddətli fəaliyyətinin davamlılığı və enerji istehsalı potensialı qiymətləndirilmişdir. Nəticələr göstərir ki, ləğv edilmiş quyulardan geotermal enerji çıxarılmasının səmərəliliyi əsasən yeraltı temperatur paylanması, istilik mübadilə sisteminin dizaynı və uzunluğu, həmçinin ətraf süxurun istilik xüsusiyyətlərindən asılıdır. Tədqiqat sübut edir ki, düzgün hazırlanmış yeraltı sistemlər etibarlı və ekoloji baxımdan məsuliyyətli bərpa olunan enerji mənbəyi təmin edə bilər. Nəticələr mövcud quyu infrastrukturlarının təkrar istifadəsi ilə enerji balansının şaxələndirilməsi, fosil yanacaqlardan asılılığın azaldılması və aşağı karbonlu enerji sistemlərinə keçidin dəstəklənməsi imkanlarını vurğulayır. Açar sözlər: Geotermal enerji, ləğv edilmiş quyular, istilik bərpası, yeraltı istilik, bərpa olunan enerji, dayanıqlı inkişaf. VOLUME 31 (07) ISSUE 07 2025 117 ON THE USE OF POLYETHYLENE PIPES IN LAYING GAS DISTRIBUTION NETWORKS Rugiya Askerova Azerbaijan State Oil and Industry University. E-mail:rugiya.askerova[email protected] ABSTRACT The advantages of polyethylene pipes in the construction of gas distribution networks compared to steel pipes are analyzed. The main advantages are low-cost, long service life and corrosion resistance. Currently, gas transportation with polyethylene pipes is carried out in several pipelines. In order to investigate the hydraulic resistance of these pipelines, studies were conducted on the polyethylene and metal parts of the gas pipelines supplying cities of Salyan and Neftchala. Researches were carried out in different pressure and consumption regimes, in summer and winter seasons. As a result of the research, it was determined that the calculated value of the hydraulic resistance in the part of the pipeline with polyethylene pipes in different modes is reduced by approximately two times compared to the metal pipes. This, in turn, makes it possible to increase productivity without changing the pressure regime (about 1.4 times compared to metal pipes). The reason for the reduction of hydraulic resistance in polyethylene pipes is that their roughness is much less than that of steel pipes (according to current standards, it is 0.0007 cm for new polyethylene pipes and 0.01 cm for new steel pipes). Keywords: polyethylene pipes, gas pipeline, pressure regime, hydraulic losses, hydraulic resistance, roughness. Introduction As it is known, the transportation of oil, oil products, gas, water, sewage flows, etc. through the metal pipes, leads to the consumption of a large volume of metal, resulting in significant financial expenses. Taking into account all this, the production of pipes from cheaper materials has become an important issue. Starting from the 1970s and 1980s of the last century, as a result of progress achieved in the petrochemical industry, complex steel pipes were partially replaced by pipes made of polymer materials [1,2]. As a result, of conducted research and tests, it was found that depending on the grade of the polyethylene pipes, their service life can range from 50 to 100 years. Automatic welding of polyethylene pipes is performed automatically ensuring the necessary reliability of joints reducing significantly human labor and improving quality. 117-124 Publication history Article received: 08.10.2025 Article accepted: 05.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-117 118 VOLUME 31 (07) ISSUE 07 2025 For example, it is sufficient to note that pipes with a diameter of up to 160 mm using technical sciences introduce innovations in reducing the volume of construction work. This, in turn significantly decreases the number of welded joints in the pipes. It should be noted that for such pipes, excavation of trenches using an excavator is also accelerated, and as a result a team of 2-3 people can install and construct more than 1 km of pipe in one day. Experiments and currently used methods in the field of polyethylene pipe application worldwide have shown that their installation and construction can be carried out using old pipes that are already in operation. That is, without performing earthworks or digging trenches for the pipeline, polyethylene can be inserted into the old pipes, thereby reducing labor volume and significantly increasing construction speed. In this case, by removing the electrical protection from the pipe, the metal pipe itself can be used as a protective pipeline. Thus, the reduction of costs associated with corrosion protection of polyethylene pipes leads to a significant decrease in construction and operational expenses, while also saving construction time. Two main advantages can be highlighted in terms of increasing the productivity of polyethylene pipes: - The hydraulic resistance coefficient of polyethylene pipes is significantly lower compared to steel pipes. - The inner surface of polyethylene pipes does not undergo corrosion or adhesion (sticking) during movement. Although the cost of polyethylene pipes is lower than that of steel pipes, the cost of welding their joints is higher. Therefore, the total construction cost of polyethylene pipes is higher than that of other pipelines materials. However, these pipes have several advantages, which are why they are widely used: - They have a long service life (50-100 years); - They do not require electrochemical protection (cathodic protection); - They are resistant to water and aggressive environments; - They are 2-4 times lighter than metal pipes; - They do not require lifting mechanisms for 12 meter sections; - Polyethylene pipes with a diameter of 20-110 mm are available in coils of 50-500 meters; - Their end-to-end welding is inexpensive and simple, does not require additional materials, and takes little time; - Preparing welds requires minimal time; - They can be stretched to some extent; - They are characterized by high elasticity and a smooth inner surface; - They are environmentally friendly and economical. The choice of polyethylene pipes is based on their field of application. In high-pressure gas pipeline construction, all-diameter pipes are joined using welding. The most common welding method is butt welding, performed with special welding equipment. The electrofusion welding method is used in systems with high safety requirements. Considering that steel pipelines are mainly used in pipeline installations, the main problem for them remains their susceptibility to external and internal corrosion, especially for industrial VOLUME 31 (07) ISSUE 07 2025 119 pipelines. Based on this, the authors in [3] substantiate the advisability of replacing steel pipelines with polymer-reinforced pipes, which are distinguished by their high corrosion resistance, low moisture absorption values, and increased dielectric properties. In the study [4] on the basis of the analysis of the state of the gas distribution network of the city of Baku conducted by the authors the technical and economic feasibility of replacing steel pipelines with polyethylene ones is substantiated. It is noted that the problems of saving fuel and energy resources all over the world occupy a leading place, both in the design and in the construction and operation of gas pipelines. This problem is also relevant for Azerbaijan, where the oil and gas industry occupy a strategic place in the economy of the country. In this regard, the use of modern energyand resource-saving technologies in pipeline gas transportation is acquiring urgent significance. Here, along with increasing operational reliability, an important place is occupied by the issues of the cost of gas pipelines, both in construction and in operation. One of the directions for solving these issues is the use of pipes made of polymeric materials for gas distribution networks. The conducted analysis of the development and the current state of the gas distribution network of the city of Baku showed that intensive gasification of the city began in the fifties of the last century, and its complete gasification was basically completed in the midseventies. It should also be noted that most underground gas distribution pipelines have outlived their service life and are subject to replacement. But significant capital investments are needed to bring underground gas pipelines into proper condition. Currently, with the aim of completely replacing steel pipelines with polyethylene ones in gas distribution networks in Azerbaijan (Sumgait city), an industrial base for the production of polyethylene pipes has been created and is successfully operating based on the purchase of modern technologies. At the same time, the use of polyethylene pipes in the construction of gas distribution networks requires solving such an important issue as the possible manifestation of non-equilibrium (viscoelastic) properties of the pipe material [5]. Here, first of all, we are talking about developing new calculation schemes for gas movement in pipeline systems, taking into account the possible manifestation of the relaxation properties of the pipe material. In order to scientifically substantiate the advantage of polyethylene pipes with respect to their low hydraulic resistance compared to the steel pipes used, this article conducted studies on selected sections of the existing gas pipeline. The methodology of the studies and the results obtained are presented below. Research methodology Depending on the type of transported material, polyethylene pipes are subjected to two types of impact – physical and chemical. Although polyethylene pipes are highly resistant to chemical compounds, hydrocarbons such as oil, gas, condensate and petroleum products can affect them, reducing the physical and mechanical strength of the pipe material. Experiments have shown that the smooth inner surface of polyethylene pipes allows for an increase in pipeline capacity by up to 20%. When transporting hydrocarbon products, the internal pressure can be reduced by up to 20% due to pipe’s resistance to the effects of the transported substances. Theory and Calculation 120 VOLUME 31 (07) ISSUE 07 2025 Calculations were performed as a result of studies conducted on the section of the existing distribution network containing the polyethylene pipes to observe the reduction in hydraulic resistance during transportation with polyethylene pipes is compared to steel pipes. The schematic diagram of the studied gas pipeline section is provided. The diagram shows there are sections of the gas pipeline constructed from metal and polyethylene pipes. The AstaraGazimammad main pipeline with a diameter of 1200 mm is used as the feeder pipeline. The pipeline starts from Astara, and the connection point is at the 151st km of the pipeline (Figure). The study included a comparative analysis of the hydraulic resistance coefficient, roughness parameters and other characteristics from both metal and polyethylene pipes. The main objective of the study was to improve the reliability of the existing distribution network by reducing hydraulic resistance and increasing productivity in the polyethylene pipeline sections supplying the cities of Salyan and Neftchala. Utilizing the advantages of polyethylene pipes, as mentioned earlier, helps ensure a stable and efficient supply of natural gas to the population, public utilities and industries both now and in the future. As it is seen from the diagram, the pipelines are constructed from polyethylene (1-5) and metal (5, 6) pipes of various diameters. The section between points 1 and 2 consists of a 250 mm diameter pipe with a length of 20 km. The section between points 2, 3 and 4 consists of a 200 mm diameter pipe with a total length of 13.4 km; the diameter of the pipe between 2 and 5 points has a diameter of 200 mm and length of 23 km. Thus, the entire polyethylene pipeline length is 56.4 km. The metal pipe section between the points 5 and 6 has a diameter of 200 mm and a length of 13 km. VOLUME 31 (07) ISSUE 07 2025 127 and hydrodynamic pressures that generate large inertial forces; this structural integrity is continuously challenged by technological factors like continuous cyclic operational loads, which cause fatigue stresses and the subsequent formation and propagation of microscopic cracks, leading to reduced structural capacity and potential failures. Monitoring of hydraulic structures The monitoring process is fundamentally important for ensuring the long-term safety, reliability, and efficiency of Offshore Hydraulic Engineering Structures (OHES). Monitoring encompasses a set of systematic activities carried out to continuously collect, analyze, and forecast information regarding the physical condition of the structure, its structural integrity, and the environmental parameters affecting it. The foundation of OHES monitoring is established by Structural Health Monitoring (SHM). These systems are designed to track changes, degradation, and damage occurring in the structural elements of the facility in real-time. SHM systems employ various types of sensors. Strain and deformation sensors utilize strain gauges placed at various points of the structure, particularly in highly stressed sections, to record changes in material stress. Monitoring the submerged parts of OHES requires specialized methods, as they are exposed to the most aggressive effects of the marine environment. Robotics and uncrewed underwater vehicles (ROV/AUV) are widely used for visual inspection, photography, video recording, as well as sonar and acoustic scanning, in depths or hazardous zones inaccessible to human divers. ROVs are controlled via a cable and possess precise maneuvering capability. AUVs autonomously collect data along predetermined routes. These devices enable the detection of cracks, corrosion, biological fouling, erosion (scouring) around the foundations, and other underwater damages. Subsea ultrasonic inspection is applied to detect hidden cracks, defects, and thickness loss in metal structures. Table 1. New tested methods. Method Model (Equipment) Application Area Result (Product) Unmanned Aircraft System (UAS / Drone) Matrice M300, Sony Alpha 7 RII, Sony RX0II Camera (Part) Images (photos), 3D surface model Unmanned Aircraft System (UAS / Drone) Elios, 1/2,3” CMOS, Lepton 3.5 FLIR Culvert (Pipeline / Pipe) Images (photos), Thermal images Terrestrial Laser Scanner Leica-P30 Camera (Part) Point cloud Handheld Triangulation Scanner Artec MHT Specific damage Point cloud Thermal Imaging Camera FLIR T660 Specific damage Thermal images Remotely Operated Vehicle (ROV) Blueprint Oculus Multibeam Sonars - M1200D Camera (Part), Specific damage Videos, Sonar Images Multibeam Sonar Teledyne SeaBat T50-P Camera (Part) Point cloud Source: A. Seiffert & J. Bödefeld. "Innovative methods for the inspection of hydraulic structures." Life-Cycle of Structures and Infrastructure Systems – Biondini & Frangopol (Eds), pp. 548-554, 2023. 128 VOLUME 31 (07) ISSUE 07 2025 The northern chamber of the Sülfeld Shipping Lock was used as a test site for performing both underwater and above-water tests. The factors leading to the selection of this test object were the possibility of completely draining the lock's water, the scheduling of the water drainage aligning with the project timeline, and the presence of various types of damage in the lock structure. Table 1 illustrates the tested methods. The inspection and data collection concerning the lock chamber's condition were performed using the Matrice M300 Unmanned Aircraft System (UAS). The Unmanned Aerial Vehicle (UAV) was flown in manual control mode, without utilizing predefined routes. An overlap of 60–70% of the images was ensured to combine the photographs via the photogrammetry method to obtain a textured 3D surface model of the lock chamber. Furthermore, these collected images were used to evaluate the potential for automatic damage detection by applying machine learning methods. Azerbaijan's oil and gas industry in the Caspian Sea also widely utilizes these modern monitoring technologies. Complex sensor networks installed on deepwater platforms, routine inspections carried out by ROVs, and environmental monitoring programs play a vital role in ensuring the reliability and environmental safety of OHES in the region. Analysis of strength, stability, and corrosion in offshore hydraulic structures Offshore Hydraulic Engineering Structures (OHES) encounter complex challenges due to their operation in the harsh and dynamic marine environment. These issues can severely impact the structural integrity, operational efficiency, and environmental safety of the facilities. The problems arising during the operation of OHES are primarily linked to a complex set of causes, broadly divided into two major groups: natural and technogenic factors. These causes interact with each other, potentially weakening the structural integrity and disrupting the functional stability of the installations. Natural factors stem from the volatile and aggressive nature of the marine environment. Hydrodynamic loads are one of the most crucial natural impacts. Strong waves, marine currents, and storms apply significant dynamic and static pressures to the submerged and above-water sections of the structure. Meteorological factors also play an important role. The force and direction of the wind, sharp temperature changes, and the formation or movement of ice sheets on the sea surface (especially in the northern parts of the Caspian Sea) impose additional loads on the structures. Technogenic factors are related to human activity, production processes, and technological errors. Internal defects arising during the manufacturing of construction materials (e.g., voids in weld seams, microcracks in steel, non-homogeneity in concrete). Design and installation errors during the construction process (e.g., incorrect placement of reinforcement, faulty foundation installation) reduce the initial strength of the structure. Accidental events such as ship collisions with platforms, fires, explosions, or structural overloading can lead to serious structural damage or total collapse. Environmental challenges The construction and operation of Offshore Hydraulic Engineering Structures (OHES) can significantly impact the marine ecosystem. These impacts manifest both directly and indirectly, harming biodiversity, degrading the quality of the marine environment, and generally disrupting the ecological balance. VOLUME 31 (07) ISSUE 07 2025 129 One of the largest environmental concerns posed by OHES is the risk of marine pollution. Oil and gas production platforms can occasionally cause oil spills, covering large areas on the sea surface and inflicting fatal damage to birds, marine mammals, and fish, while also making ecosystem recovery difficult for years. Wastewater, chemical reagents, drilling waste, and metal ions discharged from facilities during operation alter the chemical composition of the seawater, reduce oxygen levels, and harm benthic organisms. In ports, fuel leaks from vessels, discharge of ballast water, and solid municipal waste negatively affect seawater quality. OHES face the problems of bio-corrosion and biofouling (attachment of marine organisms). Biocorrosion is linked to the accelerated rate of metal corrosion caused by microorganisms in seawater (e.g., sulfate-reducing bacteria). These bacteria form biological films on the metal surface and promote electrochemical reactions that accelerate corrosion processes. Biofouling is the process where mussels, barnacles, seaweeds, and other marine organisms attach to the submerged parts of the structures and form colonies. This process increases the hydrodynamic resistance of the structures, which leads to increased current loads or reduced vessel speed. Implementation of new technologies against problems in offshore hydraulic structures Continuous advancements in engineering and technology facilitate the application of new and innovative methods in the struggle against the multifaceted problems faced by Offshore Hydraulic Engineering Structures (OHES). These new approaches aim to prolong the lifespan of the structures, enhance safety, reduce maintenance costs, and minimize environmental impacts. One of the most essential new methods is the application of smart materials and composites. Traditional materials are being replaced by materials with particularly high strength, corrosion resistance, and resistance to fatigue stresses (e.g., titanium alloys, specialized polymer composites, stainless steels). Research on self-healing materials holds great promise for the future, as these materials can automatically repair microcracks as they form. Furthermore, coatings developed using nanotechnologies provide more effective corrosion protection, increase the surface's resistance to biofouling, and reduce energy consumption. Digital Twins technology is leading to revolutionary changes in the management of OHES. A Digital Twin is a virtual replica of the physical structure, continuously updated with data collected in real-time from sensors. This enables engineers to simulate the structure's operational characteristics, potential failures, and stress points in a virtual environment, test repair scenarios, and make optimized decisions. Digital Twins ensure sustainable management throughout the structure's life cycle, from the design phase to the end of operation. Figure 1: The Digital Twin Technology. 130 VOLUME 31 (07) ISSUE 07 2025 Source: https://www.motioncontroltips.com/what-are-digital-twins-how-are-they-used-inindustrial-manufacturing/ Ecology-related challenges are also being addressed with new methods. Systems based on "Zero Discharge" principles prevent the dumping of waste from oil and gas production platforms into the sea. All production and domestic waste are either treated and reused or transported onshore for disposal. Methods like hydraulic sandfill or the placement of artificial protective structures are also applied to prevent the erosion of the seabed. The use of alternative energy sources (wind, solar) for power supply in OHES reduces carbon emissions and shrinks the ecological footprint. Progress and future trends OHES are continuously subjected to fatigue and aging processes. Cyclic stresses applied by wave, wind, and current loads at sea eventually cause the formation and propagation of microscopic cracks in structural elements, particularly in the welded joints of steel structures. The growth of these cracks reduces the material's strength and can ultimately lead to structural failure. Defects in the quality of construction materials pose a key problem for the reliability of OHES. These defects can arise: During material production (e.g., microcracks in steel, non-homogeneity in concrete). If transport or storage conditions are violated. During the construction process (e.g., improper preparation or placement of concrete, poor quality of steel welding). Based on the research findings, it is possible to propose a series of general recommendations for resolving the problems of offshore hydraulic engineering structures. Integrated Design and Life Cycle Analysis (LCA): Implement a systematic approach that holistically considers environmental, economic, and safety factors across all phases, from design and material selection to operation and decommissioning. The project's overall cost and impact must be optimized through Life Cycle Analysis (LCA). Acceleration of Digital Transformation: Promote the widespread adoption of Building Information Modeling (BIM), Digital Twins, and Artificial Intelligence (AI)-based predictive analytics. This will ensure accurate structural monitoring, enhanced risk forecasting, and the execution of agile, data-driven decisions. Table 2. Problems and Solutions. Section Core Problem and Complex Factors Current Solutions and Achievements Future Research and Development Directions (Recommendations) OHES Problem Analysis. Corrosion, wave/current loads, seismic activity, soil erosion, icing, sea level rise. High-strength concretes, FRP (Fiber-Reinforced Polymers), stainless steel alloys. Self-healing materials, materials that detect corrosion early and activate protective systems. Technological and Ecological Risks. Fatigue, aging, material defects, construction errors, operational inefficiency, navigation risks, the human factor. Cathodic protection, protective coatings, reinforcement with carbon fibers. Precise modeling and minimization of seabed erosion (scouring) and sedimentation processes. VOLUME 31 (07) ISSUE 07 2025 131 Technological and Ecological Risks. Marine pollution, biocorrosion, biofouling, physical disruption of the ecological system. Robotics, uncrewed underwater vehicles (ROV/AUV), 3D printing technologies. Reduction of the carbon footprint, integration of CCS (Carbon Capture and Storage) technologies into OHES. General Recommendations and Strategic Directions. These factors lead to degradation, reduced stability, and increased accident risks. Remote monitoring (SCADA, IoT), predictive maintenance strategies, seismic isolation. Development of specialized AI/Machine Learning models (predicting structural aging). General Recommendations and Strategic Directions. Integrated design and application of "Life Cycle Analysis.". Complex geological/hydrometeorological surveys, Emergency plans, Compliance with international standards. Design of new OHES types for the integration of offshore renewable energy sources (Wind, Wave, Current), considering the Caspian Sea potential. General Recommendations and Strategic Directions. Acceleration of digital transformation (BIM, Digital Twins, AI). Green technologies, environmental protection measures, continuous ecological monitoring. In-depth analysis of the impact of sea level rise and extreme weather events on OHES design requirements. New Research Directions: Focus on the development of novel Offshore Hydraulic Engineering Structure (OHES) types for integrating offshore renewable energy sources (wind, wave, current); the precise modeling of seabed erosion (scouring) and sedimentation; the reduction of the carbon footprint (including Carbon Capture and Storage - CCS technologies); and the in-depth study of climate change impacts on OHES design requirements (e.g., sea level rise and extreme weather events). Conclusion One of the main objectives of the research, which was the comprehensive analysis of OHES problems, has been successfully completed. It was found that these structures are exposed to the complex effects of both natural (corrosion, wave and current loads, seismic activity, soil erosion, icing, sea level rise) and technogenic (fatigue and aging, material defects, construction and installation errors, operational and maintenance inefficiency, navigation risks, the human factor) factors. These factors lead to the degradation of structures, reduced stability, and elevated accident risks. Furthermore, attention was drawn to the ecological problems that OHES can cause, such as marine environment pollution, biocorrosion and biofouling, as well as the physical disruption of the marine ecosystem. The implementation of new-generation materials, such as high-strength concretes, fiber-reinforced polymers, and stainless-steel alloys, significantly increases material durability and corrosion resistance. Corrosion protection methods like cathodic protection and protective coatings are also of critical importance. Solutions such as energy absorption systems, stable foundation systems, and seismic isolation are applied to enhance resistance against dynamic loads. The development of modern construction and repair technologies also makes significant contributions to solving problems in this field: Robotics and uncrewed underwater vehicles (ROV/AUV) make inspection and repair work in deep waters safer and more efficient. 3D printing technologies accelerate the production of complex components. Remote monitoring systems (SCADA, IoT) enable real-time control over the condition of the facilities and the 132 VOLUME 31 (07) ISSUE 07 2025 application of predictive maintenance strategies. Methods like carbon fiber reinforcement extend the service life of existing structures. Finally, the objective set regarding risk management and preventative measures has also been broadly addressed. Conducting complex engineeringgeological and hydrometeorological surveys. Preparing emergency plans for accident scenarios. Ensuring compliance with international standards. Implementing continuous operation and maintenance programs fundamentally enhance the safety of OHES. In the field of environmental safety, the application of green technologies, environmental protection measures, and continuous ecological monitoring systems are essential for the protection of the marine ecosystem. These research areas will ensure the future development of offshore hydraulic engineering and enable humanity to utilize marine resources more efficiently and safely. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES 1. Ə.C.Məmmədov, V.V.Məmmədova. Dəniz hidrotexniki qurğularının tarixi, metodologiyası və müasir problemləri. Dərs vəsaiti. Bakı, AzMİU, 2019, 162 səh. 2. Subrata K. Chakrabarti. Handbook of Offshore Engineering. Elsevier Ltd, Oxford. Vol 1. 2005. 3. Al'khimenko A. I. Bezopasnost' morskikh gidrotekhnicheskikh sooruzheniy 2003. 288 s. 4. Kul'mach P. P. Morskiye gidrotekhnicheskiye sooruzheniya. Chast' I. Osnovy morskoy gidrologii i ograditel'nyye sooruzheniya L.LVVISU. 1990. 199 s. 5. Ivanov V.I., Fadin I.M. Inzhenernaya ekologiya i prirodopol'zovaniye. - M.: Logos, 2003. - 527 s VOLUME 31 (07) ISSUE 07 2025 133 6. Todt F., Korroziya i zashchita ot korrozii. Korroziya metallov i splavov. Metody zashchity ot korrozii, per. s nem., M. L., 1966; 7. P. MakKaun. Nanotekhnologii: Shag v budushcheye \ Nanotekhnologii: Shag v Budushcheye. - M.: «Vil'yams», 1999.- S. 27 8. Seiffert & J. Bödefeld. "Innovative methods for the inspection of hydraulic structures." Life-Cycle of Structures and Infrastructure Systems – Biondini & Frangopol (Eds), pp. 548-554, 2023. 9. Wang, L., & Garcia, A. Harnessing the Potential of Autonomous Underwater Vehicles in Pipeline Inspection and Maintenance. Marine Technology Review (2023), 20(2), 78-89. 10. Qin Chen, Lixia Wang, Haihong Zhao, Douglass S.L. Prediction of Storm Surges and Wind Waves on Coastal Highways in Hurricane-Prone Areas // Journal of Coastal Research. 2007. Vol. 23. Iss. 5. P. 1304–1317. https://doi.org/10.2112/05-0465.1. 11. SP 369.1325800.2017. Morskiye statsionarnyye platformy. Pravila proyektirovaniya. AO «VNIIG im. B.Ye. Vedeneyeva». M.: Standartinform. 2018. 32 s. 12. SP 11-114-2004. «Inzhenernyye izyskaniya na kontinental'nom shel'fe dlya stroitel'stva morskikh neftegazovykh ob"yektov» / Gosstroy Rossii. — M.: Proizvodstvennyy i nauchno-issledovatel'skiy institut po inzhenernym zrachkam v stroitel'stve (FGUP «PNIIIS») DƏNİZ HIDROTEXNİKİ QURĞULARIN MÜASİR PROBLEMLƏRİ VƏ ONLARIN ARADAN QALDIRILMASI ÜSULLARI Rita Hüseynova1 Rüfət Hacıəliyev2 1.2“Qaz-Neft-Mədən” fakültəsi, Azərbaycan Dövlət Neft və Sənaye Universiteti. 1Dosent, texnika elmləri namizədi, rita.huseynov[email protected] 2Magistr, ruf[email protected] XÜLASƏ Dəniz hidrotexniki qurğularının quraşdırılması neft, qaz və digər mayelərin çıxarılması və saxlanılması üçün vacib olan mürəkkəb mühəndislik konstruksiyalarıdır. Suyun dərinliyi, dəniz dibinin tərkibi və ətraf mühit qaydaları kimi müxtəlif amillər hidrotexniki qurğuların tikinti və quraşdırma metodunun seçilməsinə təsir göstərir. Bu qurğular həm təbii amillərin (korroziya, dalğa və cərəyan yükləri, seysmik aktivlik, torpaq eroziyası, buzlanma, dəniz səviyyəsinin qalxması), həm də texnogen amillərin (yorulma və qocalma, material qüsurları, tikinti və quraşdırma səhvləri, istismar və təmirin effektivsizliyi, naviqasiya riskləri, insan faktoru) birgə təsirinə məruz qalır. Bu amillər konstruksiyaların deqradasiyasına, dayanıqlığının azalmasına və qəza risklərinin artmasına səbəb olur. Dərin su qurğuları tez-tez dəqiq əməliyyatlar üçün uzaqdan idarə olunan nəqliyyat vasitələri (ROV) və avtonom sualtı nəqliyyat vasitələri (AUVs) kimi qabaqcıl texnologiyalar tələb edir. Bundan əlavə, DHQ-ların ekoloji problemlərə – dəniz mühitinin çirklənməsinə, bio-korroziya və bioloji çirklənmə, eləcə də dəniz ekoloji sisteminin fiziki pozulmasına səbəb ola biləcək potensial təsirlərini qiymətləndirmək üçün ətraf mühitə təsirin qiymətləndirilməsi aparılır. Məqalədə dəniz hidrotexniki qurğularının problemlərinin həlli yollarına dair müxtəlif üsulların tətbiqinin analizi aparılmış, baş verən çətinliklər, mürəkkəbləşmələr vurğulanmış, məsələnin hal- 134 VOLUME 31 (07) ISSUE 07 2025 hazırdakı və gələcəkdəki aktuallığı barədə fikirlər bildirilmişdir. Burada əsas məqsəd dəniz tikintisinin və neft, qaz ehiyatlarının istisamarının əsasını təşkil edən dəniz hidrotexniki qurğuların tikinti mexanizmi və metodları haqqında ümümi məlumatın verilməsi nəzərdə tutulmuşdur. Açar Sözlər: dəniz hidrotexniki qurğuları, dəniz tikintisi, müasir tikinti və təmir texnologiyaları, qurğuların vəziyyətinə real vaxt rejimində nəzarət metodları, tikinti problemləri. СОВРЕМЕННЫЕ ПРОБЛЕМЫ МОРСКИХ ГИДРОТЕХНИЧЕСКИХ СООРУЖЕНИЙ И МЕТОДЫ ИХ УСТРАНЕНИЯ Рита Гусейнова1 Руфат Гаджиалиев2 1,2Раздел «Газ-Нефть-Добыча», Азербайджанский государственный нефтяной и промышленны университет 1Доцент, кандидат технических наук, rita.huseyno[email protected] 2Мастера, rufat.hajialiy[email protected] РЕЗЮМЕ Морские гидротехнические сооружения (МГС) — это сложные инженерные конструкции, которые имеют решающее значение для добычи и хранения нефти, газа и других жидкостей. Различные факторы, такие как глубина воды, состав морского дна и экологические нормы, влияют на выбор метода строительства и монтажа гидротехнических сооружений. Эти конструкции подвергаются комбинированному воздействию как природных факторов (коррозия, волновые и течения нагрузки, сейсмическая активность, эрозия грунта, обледенение, повышение уровня моря), так и техногенных факторов (усталость и старение, дефекты материалов, ошибки при строительстве и монтаже, неэффективность эксплуатации и ремонта, навигационные риски, человеческий фактор). Эти факторы приводят к деградации конструкций, снижению их устойчивости и увеличению рисков аварий. Глубоководные сооружения часто требуют передовых технологий, таких как дистанционно управляемые аппараты (ROV) и автономные подводные аппараты (AUVs), для выполнения точных операций. Кроме того, проводится Оценка Воздействия на Окружающую Среду (ОВОС) для оценки потенциального влияния МГС на экологические проблемы, включая загрязнение морской среды, биокоррозию и биообрастание, а также физическое нарушение морской экологической системы. В статье проведен анализ применения различных методов для решения проблем морских гидротехнических сооружений, подчеркнуты возникающие трудности и осложнения, а также высказаны мнения о текущей и будущей актуальности этого вопроса. Основная цель здесь — предоставить общую информацию о механизме и методах строительства морских гидротехнических сооружений, составляющих основу морского строительства и освоения запасов нефти и газа. Ключевые слова: морские гидротехнические сооружения, морское строительство, современные технологии строительства и ремонта, методы мониторинга состояния сооружений в режиме реального времени, проблемы строительства. VOLUME 31 (07) ISSUE 07 2025 135 ON THE INFLUENCE OF STRUCTURAL CHANGES ON PRESSURE LOSSES IN MULTIPHASE GRAVITATIONAL FLOWS Gafar Ismayilov1, Mahabbat Agasenli2, Gulnara Zeynalova3 1Professor of Azerbaijan State Oil and Industry University. e-mail: [email protected]1, 2PhD student of Azerbaijan State Oil and Industry University. e-mail: [email protected] 3Lecturer of Azerbaijan State Oil and Industry University. e-mail: guln[email protected]3 ABSTRACT In oil and gas field practice, multiphase flows (oil and gas, oil and gas-water, gas-mechanical particles, oil and mechanical particles, gas-condensate, etc.) are very widespread. Analysis shows that, compared to single-phase flows, multiphase flows have higher technological difficulties and operating costs. Due to multiphase, the reliability and useful work coefficient of pipelines and risers are lower. The article shows the possibility of increasing the reliability of such systems by taking into account the interaction of phases in accordance with a new physical flow model. For example, it was possible to increase the efficiency of technological processes by selecting the optimal diameter of multiphase pipelines. Keywords: Risk, technological difficulty, multiphase, fountain lift, optimal diameter. Introduction The experience of offshore field exploitation shows that, depending on the conditions, not only the collection and even the transportation of well products is often carried out without phase separation, that is, in a multiphase manner [1 5] . Due to the extreme nature of offshore conditions, the collection and transportation of natural and associated petroleum gases is often accompanied by the formation of a liquid phase and its precipitation in pipelines. The analysis shows that, due to the multiphase flow, the "well-gathering" system operates in a pulsating mode. Due to the periodic accumulation and discharge of condensate at the well bottom (in the casing), pulsations are observed in the dynamics of the wellhead pressure and the initial and final pressures in the gas pipeline. Multiphase flows are very common in gas lift risers. Oil, gas, and even water entering the lift from the formation are in the form of multiphase mixtures. These mixtures change their properties as they move along the riser. In general, one of the important problems for multiphase flows is related to technological difficulties. In many cases, these difficulties can be further complicated by the relief, or rather, by flows directed from bottom to top and from top to bottom. For such flows, the physicochemical and rheological properties of the flow differ from each other, and gravitational losses are of 135-141 Publication history Article received: 08.10.2025 Article accepted: 05.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-135 136 VOLUME 31 (07) ISSUE 07 2025 particular importance. Thus, while the gravitational force increases the resistance to movement in the ascending parts of the route, it reduces the resistance of the pipeline in the descents. The pressure losses due to gravitational forces can be estimated as follows: (1) Here: and - are the gravitational losses in the ascending and descending sections, respectively; and - are the flow densities in the ascending and descending sections, respectively; and - are the heights of the ascending and descending sections, respectively. Considering that , in addition to ascending and descending sections, there are also linear (horizontal) sections for offshore pipelines, and in this section there are no gravitational losses and mainly friction losses ( ) are important, then to determine the total pressure losses for a offshore pipeline with complex relief, we can write: (2) Considering that the height of the vertical sections is much smaller than the linear section, friction losses for these flows are not taken into account in expression (2). considering the expression, then the following expression can be written to determine the total pressure losses for a multiphase pipeline: (3) Here: a=1.087 b= and - the density and hydraulic resistance coefficient of the mixture, respectively; - the volume flow rate of the mixture; Qthe flow rate of the mixture. As it can be seen from the obtained expression (3), the flow characteristic of a multiphase pipeline differs significantly from that of a single-phase pipeline (Fig. 1). If the minimum pressure for a single-phase flow is equal to the pressure at the end of the pipeline, then for a multiphase pipeline this pressure divides the multiphase flow structure into two parts, as Figure 1. shows thus, from this point to the right the flow is homogeneous, dispersed or emulsified, and from the minimum point to the left the flow is stratified, i.e., separated into phases. VOLUME 31 (07) ISSUE 07 2025 143 Furthermore, such machining simplifies the technological process, reduces energy consumption, and significantly extends the operational life of components. The machining of internal cylindrical surfaces by plastic deformation is particularly important in the manufacturing of internal combustion engines. The surface quality of cylinders directly affects engine fuel consumption, power, and durability. For instance, conventional turning and honing methods leave microscopic irregularities on the surface, which increase friction and fuel consumption during operation. However, machining by plastic deformation creates smoother and stronger surfaces, thereby reducing fuel consumption, increasing operational life, and extending maintenance intervals. Moreover, the application of plastic deformation machining is not limited to engine cylinders. This method is also widely used in the manufacturing of hydraulic cylinders, compressor chambers, high-pressure pipelines, and pump components. All of these elements operate under high pressure and friction; thus, their internal surface strength and deformation resistance are critical requirements. One of the main technological advantages of plastic deformation machining is that it not only improves surface quality but also generates residual compressive stresses in the internal structure of the material. These stresses increase fatigue strength and enable the working surface to withstand loads for an extended period. For this reason, such methods are gaining preference in the production of high-responsibility structural components. From a scientific and practical perspective, this topic is relevant for Azerbaijan, where the machine-building industry is rapidly developing. The application of modern technologies is crucial to enhance the competitiveness of local production facilities. The high-quality machining of internal cylindrical surfaces is especially important in the oil-gas industry, agricultural machinery, and vehicle manufacturing sectors. Therefore, the study and industrial application of plastic deformation methods are among the key priorities for the national economy. Research on this topic has both theoretical and practical significance. From a theoretical standpoint, it allows the analysis of deformation mechanisms, applied forces, and the distribution of stresses and strains. From a practical standpoint, the results contribute to the development of modern tools, devices, and technological processes. Consequently, the study of machining internal cylindrical surfaces by plastic deformation is particularly important for improving industrial efficiency and extending the service life of components. The selection of this topic is not accidental, as the enhancement of material strength and reduction of production costs remain major industrial objectives. Therefore, this research primarily aims to study the mechanisms of plastic deformation machining of internal cylindrical surfaces. Purpose of the study The main objective of this research is to study the theoretical and practical foundations of machining internal cylindrical surfaces using plastic deformation methods, to scientifically substantiate their advantages, and to investigate the structural features of mechanisms that enable their implementation. For this purpose, the study compares existing machining methods with plastic deformation methods in terms of accuracy, surface quality, strength, and economic efficiency. 144 VOLUME 31 (07) ISSUE 07 2025 A distinctive feature of this work is that the research is not limited to theoretical approaches but also provides practical solutions applicable in industry. It examines the design, working principles, application areas, and stress-strain conditions of tools and mechanisms used in plastic deformation machining. Research object and test methods The research object of this study includes the tools, devices, and technological mechanisms used in machining internal cylindrical surfaces by plastic deformation. The main focus is directed toward improving surface quality, increasing strength, and extending service life. In this research, to determine the efficiency of the machining process by plastic deformation, the following test methods were used: Static Load Test Conducted to study the influence of the applied force on deformation depth. The degree of surface deformation under different pressure forces is measured. Dynamic Test (Impact or Vibration) Performed to study the effect of rotational speed and vibration changes on the thickness of the plastic layer during machining of rotating cylindrical parts. Temperature Test Investigates the influence of surface temperature on the material’s yield strength and surface quality during machining. Surface Roughness Measurement After machining, the surface roughness parameters (Ra, Rz) are measured using a profilometer to evaluate the ability of plastic deformation to improve surface quality. Hardness and Mechanical Stress Test Determines residual stress and hardness distribution in the internal surface using the Brinell or Vickers methods. Microstructural Study Examines the internal structure of the material after machining, including dislocation density, grain size, and texture changes using an optical microscope. Wear Resistance Test Evaluates the wear resistance of machined surfaces under operational conditions using a tribological testing machine. The conducted experiments showed that: With increasing applied pressure, the deformation depth increases; however, beyond a certain limit, microcracks appear. The optimal pressure range was determined as 300–500 N. Increasing the rotational speed generates thermal effects, causing localized softening of the material and resulting in a smoother surface. However, excessive speeds lead to thermal deformation. The optimal rotational speed range was 800–1000 rpm. The influence of temperature was clearly observed during testing. In the 80–120°C range, the yield strength of the material decreases, ensuring uniform deformation. Surface roughness parameters achieved were Ra = 0.4–0.6 μm, representing a 25–30% improvement over conventional cutting methods. Post-machining hardness increased by 15–20%, attributed to the compaction effect of plastic deformation. VOLUME 31 (07) ISSUE 07 2025 145 Microstructural analysis revealed that a fine-grained structure formed in a 0.1–0.3 mm thick surface layer, with increased dislocation density, leading to higher mechanical strength. Wear resistance tests showed that surfaces machined by plastic deformation demonstrated 1.5–1.7 times higher wear resistance. Practical significance This research is of particular importance for Azerbaijan’s industry. Extending the operational life of equipment used in the oil and gas sector, agricultural machinery, and transport vehicles directly impacts national economic growth. The obtained results not only provide a theoretical foundation but also serve as practical recommendations for industrial enterprises. The experiments were conducted at the “Bibiheybat OGP” facility in compliance with GOST standards. Conclusion The machining of internal cylindrical surfaces by plastic deformation has become one of the major issues in modern mechanical engineering. The operational capacity and longevity of technical devices, vehicles, engines, and industrial equipment depend heavily on the quality of their internal surfaces. Cylindrical components working under high pressure and friction are prone to wear, cracking, and failure, increasing maintenance costs and causing production interruptions. Therefore, the selection of this topic is not accidental. This study focuses on meeting one of today’s key industrial challenges – ensuring the long-lasting and reliable performance of components through new machining methods. Traditional machining methods using cutting tools are still widely used today. However, their capabilities are limited. While they can achieve certain precision, they do not increase material strength or wear resistance; in fact, cutting sometimes weakens the material’s structure, causing premature failure. Plastic deformation machining, on the other hand, is fundamentally different: the material is not cut, but compressed and strengthened under special forces, changing internal stresses and extending service life. For this reason, plastic deformation has become one of the most demanded machining technologies in modern industry. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. Acknowledgments The author would like to thank for the support staff and experienced people who participated in this study by sharing their invaluable knowledge and experience. Their cooperation and openness contributed greatly to the depth and richness of the research results. Competing Interests The authors declare no competing interests. Funding Source 146 VOLUME 31 (07) ISSUE 07 2025 This research was conducted without support from external funding. Ethical Standards The research meets all ethical guidelines, including adherence to the legal requirements of the study country. REFERENCES 1. Abbasov, V. A., & Bashirov, R. C. (2019). Manufacturing Technology of Metal Tools. Baku: Elm Publishing, No.1, pp. 72–75. 2. Hasanov, A. A., & Aliyev, M. A. (2010). Strength of Materials, No. 3 (67), pp. 26–29. 3. Huseynov, A. M. (2020). Methods of Strengthening Industrial Parts. Sumqayit: Industrial Publishing, 18–19 November, Vol. I, pp. 103–106. 4. Mammadov, N. M. (2020). Machining of Oil and Gas Equipment Parts. Baku: SOCAR Publishing, No.10, pp. 54–57. 5. Gasimov, Sh. Y. (2016). Materials Science and Technological Processes. Baku: Education Publishing, No.12, pp. 52–54. ИССЛЕДОВАНИЕ МЕХАНИЗМОВ ОБРАБОТКИ ВНУТРЕННИХ ЦИЛИНДРИЧЕСКИХ ПОВЕРХНОСТЕЙ ПУТЕМ ПЛАСТИЧЕСКОЙ ДЕФОРМАЦИИ Расим Баширов¹, Демирэл Рамазанов² ¹Профессор, Кафедра «Теория машин и механизмов», Бакинский инженерный университет, Азербайджан. Email: [email protected] ²Магистрант, Кафедра «Теория машин и механизмов», Бакинский инженерный университет, Азербайджан. Email: [email protected] РЕЗЮМЕ Применение новых технологий играет важную роль в развитии современного машиностроения и производственных процессов. В частности, долговечность и надежная работа различных деталей машин, цилиндров двигателей, насосного и компрессорного оборудования зависят от качества их внутренних поверхностей. Основное преимущество методов пластической деформации заключается в уплотнении и упрочнении микроструктуры металлических поверхностей, что повышает долговечность и срок службы. Этот метод предотвращает появление следов режущего инструмента на поверхности, снижает вероятность образования трещин и улучшает качество поверхности. Обработка внутренних цилиндрических поверхностей методом пластической деформации напрямую влияет на расход топлива, мощность и долговечность двигателей внутреннего сгорания. Проведённые исследования показывают, что обработка внутренних поверхностей методом пластической деформации значительно повышает пластическую прочность и износостойкость деталей двигателя. VOLUME 31 (07) ISSUE 07 2025 147 Ключевые слова: деформация, качество поверхности, внутренние цилиндрические поверхности, машиностроение, цилиндры двигателей. DAXİLİ SİLİNDRLİ SƏTHLƏRİN PLASTİK DEFORMASİYA METODU İLƏ EMAL MEKANİZMİNİN TƏDQİQİ Rasim Bashirov1, Dəmirəl Ramazanov2 1Professor, “Maşınlar və Mexanizmlər Nəzəriyyəsi” kafedrası, Bakı Mühəndislik Universiteti, Azərbaycan. E-mail: [email protected] 2Magistr tələbəsi, “Maşınlar və Mexanizmlər Nəzəriyyəsi” kafedrası, Bakı Mühəndislik Universiteti, Azərbaycan. E-mail: ramazanov.dem[email protected] XÜLASƏ Müasir maşınqayırma və istehsalat proseslərinin inkişafında yeni texnologiyaların tətbiqi mühüm rol oynayır. Xüsusilə də müxtəlif maşın detallarının, mühərrik silindrlərinin, nasos və kompressor avadanlıqlarının uzunmüddətli və etibarlı işləməsi onların daxili səthlərinin keyfiyyətindən asılıdır. Plastiki deformasiya üsullarının əsas üstünlüyü ondadır ki, metal səthlərdə mikrostrukturun sıxlaşdırılması və möhkəmləndirilməsi hesabına səthin davamlılığı və istismar müddəti artır. Bu üsul səthdə kəsici alət izlərinin yaranmasının qarşısını alır, çatların əmələgəlmə ehtimalını azaldır və səth keyfiyyətini yüksəldir. Daxili silindrik səthlərin plastiki deformasiya ilə emalı daxili yanma mühərriklərinin yanacaq sərfiyyatına, gücünə və uzunömürlülüyünə bilavasitə təsir göstərir. Aparılmış tədqiqatlar göstərir ki, daxili səthlərin plastiki deformasiya üsulu ilə emalı mühərrik hissələrinin plastiki möhkəmliyini və aşınmaya qarşı davamlılığını əhəmiyyətli dərəcədə artırır. Açar sözlər: deformasiya, səth keyfiyyəti, daxili silindrik səthlər, maşınqayırma, mühərrik silindrləri. 148 VOLUME 31 (07) ISSUE 07 2025 THE ROLE OF Ag ALLOYING IN MODIFYING THE STRUCTURE AND CORROSION RESISTANCE OF Mg–Zn ALLOYS Konul Amirmatova1, Gunay Aliyeva2 1J.Researcher. Azerbaijan State Oil and Industry University. Email: amirm[email protected]. ORCID ID 0000-0002-6223-7623 2J.Researcher. Azerbaijan State Oil and Industry University. Email: gunkaa[email protected] ABSTRACT This review examines recent studies on how silver (Ag) affects the corrosion resistance of Mg–Zn alloys, which are actively explored as biodegradable materials for temporary medical implants. The main challenge remains the high corrosion rate of magnesium in physiological environments. Ag is highlighted as an alloying element that can slow degradation by refining microstructure, stabilizing protective surface layers, and providing antimicrobial functionality. The review discusses how Ag influences electrochemical behavior, microstructural evolution, interphase interactions, and passive film formation. Findings based on SEM, XRD, potentiodynamic polarization, and EIS are summarized. Biomedical aspects such as biocompatibility and antibacterial performance are also considered. Overall, Ag addition notably enhances the corrosion resistance of Mg–Zn alloys, supporting their potential for next-generation biodegradable implants. Keywords: Mg-Zn-Ag, Mg-Zn, biomaterials, structure, corrosion. Introduction The development of biodegradable metallic materials is gaining significant interest in biomedicine, especially for temporary implants such as orthopedic screws, stents, and suturing elements. Magnesium alloys are among the most promising candidates due to their biocompatibility, bone-like density, and ability to gradually dissolve in the body. However, their main limitation is a high corrosion rate, which may cause premature loss of mechanical integrity and hydrogen evolution. [1] The concept of resorbable magnesium clips was first proposed by Andrews in 1917 and later developed in a 1986 patent by R. Jorgensen. Although various Mg–Al, Mg–Cd, and Mg–Zn alloys were tested, they were too brittle and insufficiently strong for surgical use. [2, 14] One way to improve magnesium performance is alloying. Silver (Ag) is of particular interest due to its combined anticorrosive and antibacterial properties. Adding Ag to Mg–Zn alloys modifies the microstructure, promotes the formation of stable protective films, and enhances corrosion resistance. Despite advances in biomaterials, titanium and stainless-steel implants remain the clinical standard. However, they come with drawbacks such as thermal sensitivity, discomfort, delayed 148-154 Publication history Article received: 09.10.2025 Article accepted: 06.11.2025 Article published online: 20.11.2025 DOI: 10.36962/ETM31072025-148 VOLUME 31 (07) ISSUE 07 2025 149 bone remodeling, excessive stiffness, and—most importantly—the need for secondary surgery to remove the implant. In many countries, up to 80% of metallic fixation devices are removed, increasing patient trauma and healthcare costs. [2,13] Magnesium implants, however, degrade too rapidly in physiological media (pH 7.4–7.6), which leads to local alkalization, inflammation, and hydrogen gas formation that can impair blood flow and damage tissues. Localized corrosion and the formation of a weak MgO/Mg(OH)₂ surface layer further accelerate degradation. Thus, magnesium is unsuitable for long-term implants but remains highly promising for temporary ones. [2, 3] This review summarizes current research on the influence of silver on the corrosion behavior of Mg–Zn and Mg–Zn–Ag alloys, focusing on corrosion inhibition mechanisms, experimental assessment methods, and their potential for clinical application. Review of Mg–Zn Alloys: Structure and Corrosion Behavior Mg and its alloys offer advantages such as the absence of thrombotic complications, but pure Mg degrades too quickly and releases hydrogen, sometimes dissolving completely within 60–90 days after implantation. [8] Alongside Mgand Fe-based biodegradable metals, zinc is also considered promising due to its osteogenic potential. However, pure Zn is too soft and brittle, while many industrial Zn alloys contain toxic elements (e.g., high Al content), raising biocompatibility concerns. Study [4] developed Zn-1X (Mg, Ca, Sr) alloys and showed that small additions of these elements significantly improved microstructure, strength, corrosion behavior, and biocompatibility, highlighting their potential for next-generation biodegradable implants. Study [5] analyzed Zn–xMg alloys produced by LPBF. Zn-1Mg showed the best balance of properties (381 MPa tensile strength, 4.2% elongation). Higher Mg contents refined grains but produced brittle Mg₂Zn₁₁ and MgZn₂ phases. Zn-1Mg scaffolds had compressive strength and Young’s modulus comparable to human bone, supporting their use in resorbable implants. Study [7] produced Zn–xMg wires (down to 0.25 mm). Alloys contained Mg₂Zn₁₁, and higher Mg reduced grain size. Zn-0.08Mg achieved yield strength >200–300 MPa, tensile strength >300–400 MPa, and >30% elongation—meeting key requirements for biodegradable stents, though timedependent strengthening requires optimization. In vivo tests showed moderate inflammatory response. Study [9] examined extruded Zn-1.2Mg. Extrusion refined grains and improved strength (UTS 362.64 MPa, elongation 21.31%). Corrosion rate increased slightly but remained acceptable. The alloy showed excellent hemocompatibility and thromboresistance. Intermetallic phases Mg₂Zn₁₁ and MgZn₂ are critical in Mg–Zn alloys, strongly influencing strength, brittleness, and corrosion behavior. Their heterogeneity accelerates galvanic corrosion, therefore phase composition must be carefully controlled when designing biodegradable implants. Review of Mg–Zn–Ag Alloys: Structure and Corrosion Behavior Interest in the Mg–Zn–Ag system began in the 1950s–1970s, mainly for aerospace and electronics. By the 1980s, phase diagrams and key intermetallics (Mg₂Zn₁₁, MgZn₂, Mg₃Ag) were established, forming the basis for later modeling. The first biomedical showed that adding up to 1.5 wt.% Ag refines grains and improves corrosion resistance, initiating biomedical research. After 2010, focus shifted to biodegradable implants, optimizing Ag content for strength, 150 VOLUME 31 (07) ISSUE 07 2025 degradation rate, and biocompatibility using SPS, extrusion, casting, and metallic glass processing [11, 13]. In study [2], Mg7Zn1Ag and Mg6Zn3Ag alloys were compared. Higher Ag content (2.5 wt.%) in Mg6Zn3Ag improved corrosion resistance, reduced mass loss, and produced a finer, more uniform microstructure due to Mg₃Ag precipitation. Study [3] examined Zn–3Mg–xAg SPS alloys. Ag promoted Mg aggregation and MgZn₂ formation; the best properties were at 1.5 wt.% Ag (UTS 273.8 MPa, elongation 10.67%, compressive strength 543.7 MPa), far exceeding pure Zn and Zn–3Mg. In study [10], Mg–3Zn–xAg alloys produced by backward extrusion showed little difference in strength but a clear trend in ductility: it increased up to 0.2 wt.% Ag (elongation 19.8%) and decreased at higher Ag. Mg–3Zn–0.2Ag also demonstrated the best corrosion resistance due to its uniform single-phase structure. Figure 1: Phase diagram of the binary Mg–Zn system indicating the regions of formation of the intermetallic phases Mg₂Zn₁₁ and MgZn₂. Study [12] confirmed similar trends for Zn–3Mg–xAg SPS alloys: optimal mechanical behavior at 1.5 wt.% Ag due to balanced strengthening and minimal defects. In study [16], Zn–Mg–Ag alloys produced by mechanical alloying showed high strength (UTS up to 435 MPa) and significant effects of Ag on corrosion: Ag increased initial degradation but promoted uniform dissolution and a shift toward calcium–phosphate corrosion products. Corrosion rates eventually stabilized at clinically acceptable levels (~11 μm/year). Study [17] on Zn–0.5Mg–x alloys showed that Ag improves structural homogeneity, corrosion resistance, and hydrophilicity — important for implants. Metallic glass studies [6,17] demonstrated that Ag (4–6 at.%) expands the glass-forming region, improves thermal stability, reduces corrosion rates, and enhances cytocompatibility. Alloys like Mg₆₇Zn₂₉Ag₄ showed uniform degradation (0.19 mm/year) and selective inhibition of tumor cell lines. VOLUME 31 (07) ISSUE 07 2025 151 Conclusion This review shows that alloying Mg–Zn alloys with silver (Ag) effectively improves their corrosion resistance, mechanical performance, and biocompatibility, making them strong candidates for biodegradable implants. Silver addition refines grains, increases microstructural uniformity, and promotes the formation of fine phases (Mg₃Ag, Mg₂Zn₁₁, MgZn₂), which reduces galvanic corrosion by balancing potentials between the matrix and intermetallics. Optimal Ag contents (≈0.2–2.5 wt.%) decrease the corrosion rate through the formation of dense passive films (Mg(OH)₂, Ag₂O) and by shifting degradation from localized to uniform. In amorphous Mg–Zn– Ag alloys, corrosion rates as low as 0.19 mm/year meet clinical requirements. Ag also enhances the strength–ductility balance (10–30% increase in strength, elongation 10–20%) and improves cytocompatibility, calcium–phosphate deposition, and antibacterial properties. As a result, Mg– Zn–Ag alloys—especially amorphous and nanocrystalline ones—offer tunable degradation, good mechanical behavior, and high biocompatibility, making them promising materials for nextgeneration biodegradable stents, orthopedic fixators, and bone implants. Declarations The manuscript has not been submitted to any other journal or conference. Study Limitations There are no limitations that could affect the results of the study. 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