Visnik of the Volodymyr Dahl East Ukrainian National University

Сoagulation purification of used motor oils

Т.І. Chervinskyi, P.І. Kazymyriv — Mon, 15 Dec 2025 00:00:00 +0000

Waste petroleum oils are toxic compounds with low biodegradability and pose a significant environmental hazard. Their release into soils and water bodies causes particularly severe ecological damage. To restore the properties of used mineral motor oils, various technological operations based on physical, chemical, and physicochemical processes are applied to remove degradation products and contaminants. However, the most challenging for regeneration are water-contaminated used oils (oil emulsions), which contain substantial amounts of water or aqueous solutions of cooling mixtures that enter the oils during emergency situations. The difficulty in regenerating such oils arises from the fact that the water present inhibits physical purification methods – such as filtration, settling, sedimentation, and dehydration by atmospheric-vacuum distillation – due to the high stability of water – oil emulsions. The study examined the coagulation behavior of used mineral motor oil in the presence of several inexpensive and commercially available coagulants, including starch, carboxymethylcellulose, sodium laureth sulfate, and cocamidopropyl betaine. The effect of the type and dosage of these coagulants on the operational properties of the purified oil was determined. The application of 10 wt.% starch at 80 °C for 30 min. resulted in complete removal of emulsified water from the waste oil, decreased the concentration of solid impurities, and slightly improved its viscosity-temperature characteristics. The incorporation of carboxymethylcellulose in the coagulation process also enabled complete removal of emulsified water, improved viscosity-temperature properties, reduced the amount of solid impurities, and lowered the acid number of the oil. In contrast, achieving the desired level of coagulation using sodium laureth sulfate required the addition of more than 20 wt.%. It was further demonstrated that cocamidopropyl betaine, used at a dosage of 10 wt.%, provided nearly complete removal of emulsified water, slightly reduced solid impurities, and improved viscosity - temperature properties. However, at a fixed dosage of cocamidopropyl betaine, the acid number of the refined motor oil increased. The effective performance of the selected coagulants in purifying used mineral motor oil was confirmed by both experimental results and IR spectroscopic analysis. The dehydrated and partially purified oil should subsequently undergo combined regeneration methods to achieve complete restoration of its operational properties.

Adaptive symmetric cryptosystem with dynamic key agreement based on deep neural networks

B.H. Mnozhynskyi — Mon, 15 Dec 2025 00:00:00 +0000

The article is devoted to the development of an adaptive symmetric cryptosystem. Key formation is performed without traditional key exchange protocols. The method is based on the synchronization of deep neural networks. The process is implemented over an open communication channel. The purpose of the study is to substantiate a new architecture for dynamic key management in the space of neural networks. The mechanism relies on neural synchronization. Cryptographic robustness and computational efficiency of the model are evaluated. The methodology integrates cryptographic analysis and neural network theory. A formalized description of algorithmic constructions is applied. An analytical assessment of computational complexity is carried out. A comparison with classical symmetric encryption schemes is performed. The result is an architecture with decentralized key agreement logic. The key is generated as a function of the internal state of the network. The algorithm covers initialization, synchronization, and key generation. The system provides cyclic updating of key material. Encryption and decryption procedures are implemented. Resistance to passive attacks is analyzed. Robustness against active forms of interference is investigated. The system counteracts interception and injection attacks. The mechanism protects against man-in-the-middle attacks. Model adaptivity reduces correlation between successive keys. Reconstruction of internal states is significantly complicated. Computational complexity remains acceptable for practical application. The neural component does not reduce system performance during long communication sessions. Practical value lies in application within distributed networks. The system operates without centralized trust infrastructure. The results are suitable for embedded computing systems. The approach is applicable to mobile and sensor networks. The model reduces dependence on asymmetric cryptography. Peak computational loads are eliminated. Future work is associated with experimental verification on hardware platforms. An in-depth analysis of resistance to combined attack vectors is planned. A separate scientific interest concerns optimization of architectural solutions.

Reasoning for the parameters of the traction system of an industrial shunting battery locomotive

Ye.S. Riabov, A.V. Kachan — Mon, 15 Dec 2025 00:00:00 +0000

The article is devoted to determining and justifying the parameters of the traction system of an industrial manoeuvring battery locomotive, the use of which in industrial enterprises will allow the renewal of the locomotive fleet with insufficiently efficient diesel locomotives. The key advantages of using such locomotives are reduced fuel and energy consumption, lower maintenance costs, and reduced harmful emissions. To determine the parameters of traction systems, an analysis of the operating modes of existing shunting diesel locomotives was performed based on data from on-board systems. Data from ChME3 diesel locomotives used for shunting at Poltava Mining and Processing Plant PJSC was processed. It was determined that energy consumption during a twelve-hour shift ranges from 404 kWh to 1031 kWh at a maximum tangential power of 250 kW. With the specified energy consumption, the capacity of the energy storage device is 1022...1874 kWh. Calculations of the parameters of an energy storage device with lithium iron phosphate cells show that the mass of the cells is 5.8…10.7 tonnes, and the volume required for their placement is 2.9…4.9 m³. To accommodate storage devices with such mass and size parameters, as well as other electrical equipment, an appropriate locomotive design is required. The power of the energy storage device is 511...937 kW, which allows the locomotive to be used for hauling work characterised by a tangential power of no more than 420 kW. To ensure the energy efficiency of the traction electric drive, it is advisable to use an energy storage device with a maximum voltage of 600 V. This allows direct connection of auxiliary system converters to the storage device. For this case, a structural diagram of the traction system is proposed.

The energy performance of traction collector and asynchronous electric drives is considered. When using traction asynchronous electric motors in combination with two-stage gearboxes, an increase in the efficiency of both the traction electric drive and a reduction in energy consumption for cooling traction electric motors is expected. When using an asynchronous traction electric drive, it is possible to create a four-axle locomotive, including when modernising the existing crew compartments of serial shunting locomotives. 3D sketches of the equipment layout on a battery locomotive and a bogie with two motorised axles are provided using the example of the ChME3 diesel locomotive.

Modeling of automated control of mining production facilities based on the wave approach

V.S. Morkun, N.V. Morkun, Y.O. Hryshchenko, А.А. Azaryan, А.М. Gritsenko — Mon, 15 Dec 2025 00:00:00 +0000

During the classification of crushed ore by size on a fine wet ore screen, various vibrations are formed in its structure, which propagate in the form of traveling waves. To describe and model the dynamic response of an object in which traveling waves propagate, it is represented as a multi-agent system. This approach is based on a wave transfer function that determines the interactions between agents and the parameters of traveling waves and describes the behavior of the system from the local point of view of its individual elements. Analysis of the obtained simulation results showed that the approach used is well suited for reflecting the general topology of wave processes in the studied structure and its overall behavior. At the same time, the applied model includes the main nodal points of the screen structure but does not reflect the wave process occurring directly on the screen surface. Solving this problem requires the use of a large number of agents with appropriate consideration of their interaction, which is quite difficult with this approach. An alternative approach based on the use of physical modeling blocks based on the Simscape® software package for Simulink®/MATLAB® is considered. The screen cloth is presented as a structure with distributed parameters, implemented for the compliance of the structure to vertical vibrations and bending. The proposed structure consists of elementary Mass-Spring-Damper blocks connected to each other by parallel spring shock absorbers. This structure provides the inertia of the canvas, while the spring damper systems ensure its compliance. The model simulates the dynamic response of the system, oscillating in response to the applied force and bending in response to the static mass imbalance. The advantage of this approach is the possibility of using any number of elementary Mass-Spring-Damper blocks with the ability to form with the necessary accuracy the distribution of both the elastic qualities of the canvas and the mass of the ore material on it. Analysis of the simulation results shows that the proposed approach allows determining, forming, and investigating various modes of ore material movement during screening to achieve optimal technological and energy performance of the process.

Modelling the procedure for determining the characteristic features of mineralogical varieties of iron ore in the process of drilling wells

N.V. Morkun, M.G. Loriya, S.M. Hryshchenko, Т.А. Oliinyk — Mon, 15 Dec 2025 00:00:00 +0000

Well drilling is the most common and resource-intensive technological operation in the extraction of minerals. The economic efficiency of this operation directly depends on the quality of automated process control, which, in turn, is determined by the completeness of its information support. The main factor affecting the results of the drilling process is the correspondence of the speed of well penetration and the resulting control actions to the physical and mechanical characteristics of the rock or its mineralogical varieties. A method is proposed to improve the efficiency of the procedure for determining the characteristic features of mineralogical varieties of iron ore in the process of drilling wells based on the simulation of the conversion of a probing electromagnetic signal in the studied environment using Simscape® physical modeling blocks for Simulink®/MATLAB®. The approach used is based on the use of an electromagnetic transducer that generates a probing pulse in iron-bearing rock with certain electrical and magnetic properties. As a result, eddy currents are formed in the studied medium, which create an induced magnetic field, affecting parameters such as the voltage on the measuring coil or its impedance. The electromagnetic properties of the medium material affect the distribution of these induced eddy currents, which changes the parameters of the measuring coil compared to the reference material. During the modeling process, the parameters of the signal measured on the secondary winding of the electromagnetic transducer were determined when the characteristics of the studied medium changed. At the same time, changes in the ratio of minerals in the composition of iron ore varieties were simulated. Analysis of the results obtained shows their strong dependence on the magnetite content in the studied medium. This complicates the recognition of iron ore varieties that include other weakly magnetic minerals with low electrical conductivity. To obtain satisfactory results from this procedure, it is necessary to include additional characteristic features of the physical properties of the object being recognized, which primarily include the parameters of the propagation of ultrasonic waves formed during the formation of an electromagnetic pulse in ferromagnetic rock.

Stabilisation of the methanol synthesis cycle based on algorithmic control of the cooling and condensation unit

О.А. Duryshev — Mon, 15 Dec 2025 00:00:00 +0000

The paper investigates the influence of the operating modes of the gas-product mixture cooling and condensation unit on the stability and economic efficiency of the methanol synthesis cycle. It is shown that uncoordinated control of air cooling devices, which is mainly implemented in manual mode, leads to significant temperature and hydraulic disturbances in the synthesis circulation circuit. This, in turn, causes fluctuations in synthesis gas consumption, changes in pressure drops at the compressor, and a decrease in the overall stability of the unit. Existing approaches to regulating heat exchange processes, in particular the use of frequency converters to control air cooling unit fans, have been analysed, and their limited effectiveness and high cost for existing production facilities have been substantiated. An alternative approach to the automation of the cooling and condensation unit is proposed, based on the principle of compensation for disturbances in the input parameters of the process. The essence of the approach lies in the use of a discrete control system with algorithmic selection of the optimal combination of operating air cooling devices, taking into account the temperature of the gas-product mixture at the unit inlet, its flow rate and the ambient temperature. This approach minimises temperature jumps at the unit outlet, reduces pressure drops and ensures a smoother transition in the methanol synthesis cycle. The advantage of the proposed solution is that it can be implemented without installing additional expensive equipment, using only existing automation and control systems. The results obtained can be used to improve the reliability and energy efficiency of existing methanol synthesis units.

The implementation of the proposed approach creates the conditions for the further integration of intelligent control methods and digital twins of technological processes, which is in line with current trends in the development of the chemical industry and the Industry 4.0 concept.

Evaluation of current methods for extending the intervals between repairs of railway wheel sets

O.V. Vorobiov — Mon, 15 Dec 2025 00:00:00 +0000

The work is devoted to solving the urgent scientific and practical problem of evaluating and systematising modern methods for improving the operational reliability and extending the inter-repair mileage of railway wheel sets. It is substantiated that wheel sets are critical safety elements, accounting for about 10% of technical equipment failures, and that the processes in the wheel-rail system directly determine the level of resource conservation in transportation. The study analyses the dominant mechanisms of rolling surface degradation: contact fatigue, abrasive wear and thermal damage. Based on the study of domestic and foreign experience, methods for extending the service life have been systematised and classified into four main groups: structural, technological, operational and track maintenance methods. It has been established that among the design measures, the priority is the introduction of adaptive repair profiles (such as DMETI, ITM) with a non-linear generatrix. This ensures conformal contact, uniform load distribution and improved kinematic stability of movement. In terms of technological methods, the effectiveness of chemical-thermal treatment and plasma hardening has been assessed. It has been determined that the main quality criterion is the creation of a surface layer with an optimal balance of hardness and viscosity, as well as the formation of residual compressive stresses, which serve as a barrier to the development of fatigue cracks. Operational methods are considered in detail, among which forced lubrication of the ‘cam-rack’ zone demonstrates the highest efficiency, allowing the friction coefficient to be reduced to 0.08-0.12 and the wear intensity to be reduced by 2.5-4 times. The importance of the wheel set rotation strategy to compensate for uneven wear (the ridges of the running axle wear 40-60% faster) is substantiated. The impact of infrastructure is also emphasised: compliance with track width tolerances and preventive rail grinding can reduce wheel repair costs by 15-25%. Based on the results of the work, it is concluded that the maximum effect is achieved through the synergy of the methods considered. For freight traffic, a combination of ridge strengthening and lubrication is recommended, and for high-speed traffic, the use of adaptive profiles. A comprehensive approach allows for a 30-50% increase in the overall service life of wheel sets and minimises the life cycle cost of rolling stock.

Іntelligent locomotive diagnostics systems as a tool for reducing accidents in railway transport

Mon, 15 Dec 2025 00:00:00 +0000

In the context of increasing competition in the transport services market, minimizing downtime and ensuring the continuity of transportation are becoming critically important. The integration of new technologies, such as intelligent systems, can be a breakthrough in increasing safety and efficiency. The work developed a conceptual model of an intelligent locomotive diagnostics system that takes into account the specifics of the functioning of railway transport. Critical parameters were identified, the monitoring of which is key for early detection of malfunctions. The developed machine learning algorithms demonstrated high accuracy in detecting anomalies and predicting failures, which significantly exceeds the capabilities of traditional diagnostic methods. Thanks to simulation modeling, it was confirmed that the implementation of such systems can reduce the number of emergency situations by up to 25%, as well as reduce the downtime of locomotives for repair. These results indicate the significant potential of intelligent systems in increasing the safety of railway transportation. The developed prototype of the system allows you to visualize data on the state of locomotives in real time, providing operational information for making management decisions. This creates the prerequisites for optimizing maintenance schedules and transition to repairs based on the actual condition, which will reduce operating costs. The proposed methodology can be used to create similar diagnostic systems for other types of rolling stock, which expands the scope of its application. The developed concept and architecture of the intelligent diagnostic system provides a comprehensive approach to monitoring and predicting the technical condition of locomotives. The proposed machine and deep learning algorithms allow for high-precision detection of anomalies and prediction of potential equipment failures at early stages. This translates diagnostics from a reactive to a proactive approach. The obtained scientific results expand the understanding of the possibilities of applying artificial intelligence in the field of railway safety. Thus, the study not only expands scientific knowledge in the field of intelligent systems, but also provides specific tools for improving the safety and efficiency of railway transport.

Development of new systems for assessing the technical condition of vehicles based on intelligent diagnostics

Mon, 15 Dec 2025 00:00:00 +0000

It has been established that a necessary condition for maintaining the competitiveness and sustainable development of the railway industry is the introduction of innovative technologies, such as intelligent diagnostics. The work has developed a conceptual model of an intelligent diagnostic system that integrates data from diverse sources, such as on-board sensors, external monitoring systems and repair databases. This allows for the formation of a comprehensive and comprehensive picture of the technical condition of the wagon at any time. The developed mathematical models and algorithms based on machine learning, in particular deep neural networks, have demonstrated high accuracy in detecting hidden defects and predicting their development. These algorithms are able to independently learn on large data sets, adapt to new conditions and identify anomalies that cannot be detected using traditional methods. The practical value of the results lies in the creation of a software prototype that implements the functions of intelligent diagnostics, which can be implemented at railway enterprises. This software provides automated monitoring, data visualization and forecasting of maintenance needs. The practical implementation of the developed solutions in the form of a software prototype demonstrates the possibility of automating diagnostic processes and transitioning to predictive maintenance. The implementation of such systems will allow optimizing repair schedules, significantly reducing operating costs and increasing the efficiency of rolling stock use. The results obtained can be used for the further development of monitoring and control systems in railway transport. This research is an important step towards creating "smart" railways, where safety and efficiency are ensured by integrating advanced information technologies. The results can serve as the basis for developing industry standards and recommendations for the application of intelligent diagnostic systems in railway transport in Ukraine. The proposed intelligent diagnostic system allows for automating the assessment of the technical condition of railway cars, reducing costs and increasing safety.

Development of intelligent systems for monitoring the technical condition of braking and automatic coupling equipment of railway rolling stock

Mon, 15 Dec 2025 00:00:00 +0000

From a scientific point of view, the work developed new mathematical models that allow for a more accurate description of the dynamic characteristics of brake systems and automatic couplings in different operating modes. The need to create unified solutions for different types of rolling stock is relevant. Integration with existing railway transport management systems is an important task. The development of scalable and flexible monitoring systems is necessary. This will allow them to be adapted to the future needs of the industry. The introduction of innovative technologies will contribute to the development of railway infrastructure as a whole. Ukraine, as a country with an extensive railway network, has significant potential for the implementation of such solutions. Increasing the competitiveness of railway transportation is a strategic goal. This research is extremely relevant for ensuring the stability and safety of the functioning of railway transport. It is aimed at solving urgent problems of the industry. This will ensure stable and safe operation of railway transport. This provides a deeper understanding of the processes occurring in the equipment. The obtained machine learning algorithms demonstrate high efficiency in detecting hidden defects and predicting potential failures, which significantly exceeds the capabilities of traditional diagnostic methods. From an applied point of view, the developed prototype of an intelligent monitoring system has shown its operability and efficiency in laboratory conditions and on test sites. The system successfully integrates data from various sensors, providing a comprehensive analysis of the technical condition of the equipment in real time. This allows you to quickly respond to changes and make informed decisions regarding maintenance. The results of the study open the way to creating industrial samples of such systems that will have a significant economic effect by reducing the accident rate and optimizing the costs of operating and repairing rolling stock. The effectiveness assessment confirmed the significant economic potential of the implementation of such systems, which is manifested in reducing operating costs and increasing transportation safety. The results of the study are a solid basis for further scientific developments in the direction of autonomous diagnostic systems.

Parametric modeling and integration with cae systems in the design of disk gear cutters in ptc creo parametric environment

О.М. Lohunov — Mon, 15 Dec 2025 00:00:00 +0000

The article addresses the urgent problem of improving the efficiency of designing complex metal-cutting tools in the context of modern mechanical engineering. The object of the study is disk gear cutters designed for cutting spur gears using the copying method. Since these tools are standardized and manufactured in sets (typically comprising 8, 15, or 26 cutters per module depending on the required accuracy), they represent an ideal object for applying parametric design automation methods. The paper substantiates the transition from obsolete modeling methods, which used approximate spline constructions based on characteristic points (characteristic of systems like APM WinMachine), to precise mathematical modeling in high-level CAD systems such as PTC Creo Parametric. The authors present a comprehensive methodology for creating a fully adaptive 3D model of a gear cutter. The core of the proposed approach is the use of the Parameters tool as a central control unit for variables (module, number of teeth, pressure angle) and the Relations tool to establish mathematical dependencies for calculating derived geometric characteristics (pitch, base, and root diameters). A significant part of the study is calculating and building the exact geometry of the cutting tooth. The article details the process of generating the involute profile using theoretical equations in Cartesian coordinates via the "Equation Driven Curve" feature, followed by mirroring the profile relative to the tooth symmetry plane. Furthermore, the specific geometry of the relief surface (backing off), which is necessary to ensure proper clearance angles during cutting, is modeled using the Archimedean spiral equation in cylindrical coordinates. Special attention is paid to design automation using the Family Table tool, which allows generating the entire nomenclature range of the cutter set from a single generic model without manual rebuilding. The article also covers the integration of the CAD model with the CAE system ANSYS for engineering analysis. It describes the sequence of static, dynamic (modal), and coupled thermal-structural analyses required to evaluate the tool's strength, vibration resistance, and thermal stability under operating loads. The result of the work is a verified technique that significantly reduces design time, minimizes errors, and prepares the model for complex strength calculations.

Іmproving the efficiency of a multi-stage device for cooling industrial factory flue gases

Mon, 15 Dec 2025 00:00:00 +0000

The article discusses the problem of cooling flue gases from industrial enterprises as one of the key areas for improving energy efficiency and environmental safety. The high temperature of waste gases complicates the operation of heat exchange and gas cleaning equipment and contributes to an increase in harmful emissions into the environment. Traditional methods of gas cooling, such as heat exchangers, have significant energy costs, corrosion resistance problems, bulky designs, high costs, and maintenance complexity. One promising approach to solving this problem is the use of Laval nozzles, which provide adiabatic expansion of the flow with the conversion of the potential energy of the gas into kinetic energy, resulting in its intensive cooling. Based on an analysis of publications related to gas cooling, it has been determined that the use of Laval nozzles is effective not only for reducing the temperature of flue gases, but also for initiating moisture condensation and separating solid and gaseous impurities, in particular carbon dioxide and water vapor. To confirm the feasibility of this approach, a simulation of a multi-nozzle device was performed in SolidWorks FlowSimulation. The constructed three-dimensional model of a multi-nozzle device takes into account the actual parameters of flue gases and shows an effective reduction in flow temperature from 120°C to 72°C at Mach numbers of 1.1–2.7. To improve cooling efficiency, it is proposed to improve the design of the multi-nozzle device by using external cooling of the nozzles with water. The results of simulation modeling of the improved design of the multi-nozzle device showed improved heat dissipation, a reduction in the temperature gradient of the walls, and a reduction in the temperature of the gas flow at the outlet to 18°C. The studies confirm the feasibility of using multi-nozzle systems with Laval nozzles in flue gas cooling lines and open up prospects for further optimization of their geometry and integration into industrial gas cleaning systems.

Research into the patterns of formation of the structure of tool high-speed steels during surface electron beam treatment

O.V. Shevchenko, D.M. Zinchenko — Mon, 15 Dec 2025 00:00:00 +0000

The objective of the research was to study the modes of electron beam hardening on the structure and properties of surface layers of tool high-speed steels. The limiting modes of electron beam hardening were determined experimentally, which allow obtaining the maximum microhardness of the hardened layer without melting the surface being treated. Based on the results of experimental studies, a comprehensive parameter of the treatment mode was proposed, according to which the intensity of heating and cooling of the surface layer of the tool can be determined - the power density of the beam. This parameter includes all other parameters of the hardening treatment mode: diameter, power, and speed of beam movement relative to the tool surface. It has been established that the maximum hardness of the hardened layer during electron beam treatment can be achieved by high-temperature hardening without melting the treated surface. Hardening without melting also ensures the formation of a highly dispersed structure throughout the entire depth of the hardened layer. Melting of the surface of a tool undergoing electron beam hardening should be considered an extremely undesirable processing option. In the case of melting of the surface layer in a tool made of high-speed steels, a significant decrease in microhardness is observed. At the same time, the surface layer contains a significant amount of residual austenite. Hardening with melting, in which a significant amount of residual austenite is formed, is the main reason for the sharp decrease in the content of carbide phases in the surface layer. Together, all this leads to a decrease in the wear resistance of tool high-speed steels. In the case of hardening with melting, there is also a deterioration in the tool's resistance to large plastic deformations at elevated temperatures in the cutting zone. It has been established that the depth of the hardened layer significantly depends on the initial structure of the steels. The maximum depth of the hardened layer in tool high-speed steels can be obtained by their preliminary heat treatment in the form of volumetric hardening and tempering. Within the framework of the experimental studies, a range of optimal values of the overlap coefficient was established, which corresponds to the minimum values of the tempering zone width.

Research into the relationship between the structure and coercive force of spring steels for the development of a method for non-destructive testing of elastic suspension elements in electric locomotives

O.V. Shevchenko, D.M. Zinchenko — Mon, 15 Dec 2025 00:00:00 +0000

The research is devoted to studying the relationship between the following characteristics of structural steels used to manufacture suspension springs for freight electric locomotives: hardness, residual deformation and coercive force. The results of testing the elastic elements of electric locomotive suspension for residual deformation under static load have shown that their optimal structure is troostite, which is formed during medium tempering. It is the troostite structure formed during medium tempering of pre-hardened steel that allows obtaining the optimal ratio of elastic characteristics of electric locomotive suspension elastic elements during their operation under alternating loads. The results of experimental studies prove that standard methods of measuring coercive force can be used to control and evaluate the final structure and mechanical properties of the elastic elements of electric locomotive suspension. Given that the quality control of springs for hardness and residual deformation is almost 100%, this allows for a significant reduction in the time spent on control operations. The coercive force of spring steels depends solely on their structural state. If there is a decarburised layer on the surface of the springs, it has practically no effect on the coercive force if the thickness of this layer does not exceed the values established by the applicable regulatory and technical documents. Thus, a slight deviation of the coercive force of the elastic elements of electric locomotive suspension from the optimal values of coercive force established in this study may indicate an excessive thickness of the decarburised layer. The presence of surface cracks on the elastic elements of electric locomotive suspension has no effect on the coercive force. In this context, the nature and mechanisms of crack formation are also irrelevant. The results of the study show that the optimal coercive force of the elastic elements of electric locomotive suspension, which corresponds to their optimal hardness, can only be determined on the basis of preliminary tests of the elastic elements of electric locomotive suspension for residual deformation. The latter parameter is the main operational characteristic of springs, which can be used to determine their suitability for use as elastic elements in electric locomotive suspension systems. The results of the research established a relationship between the structure and residual deformation under static load of elastic elements in electric locomotive suspension systems.