Journal of Transsib Railway Studies V.1(45), 2021

At this time, an urgent area of development in the field of railway transport is the reduction of operating costs for maintenance and repair of collector traction motors . The analysis of data from the monitoring of new rolling stock shows that one of the elements affecting the reliability during the operation of traction motors is the collector-brush unit. Failures associated with unsatisfactory operation of the collector-brush unit elements reach 30% of the total number for traction motors. At work of traction electric motors there is a continuous process of mechanical, electric and chemical interaction of electric brushes with a collector, leading to deterioration of electric brushes. During the research, the authors proposed a mathematical model to determine the intensity of wear of electric brushes. The paper provides information about developing an approach that allows using the operating data recorded by locomotive on-board parameter monitoring system to determine the service life of traction motor brushes. For elimination of the problem connected with processing of big arrays of parameter values for calculation, in mathematical model of intensity of wear of electric brushes it is offered to divide the received data into intervals with definition of average values and probability of approach for each of them, and also the technique on realization of the offered decision is resulted. The developed approach allows us to eliminate the need for long-term wear tests on traction motors in operation and reduce not only time, but also financial costs. The reliability of the developed method was assessed by comparing the wear values of different types of electric brushes installed on locomotive traction motors in operation with the calculated values.

The article describes the study of the mechanical characteristics of polymer insulation, in particular the hardness of the insulating lacquer layer with a different methods of drying it. The influence of the hardness and elasticity of the dried impregnating material on the reliability of the insulating structures during the operation of electrical equipment of the traction rolling stock is analyzed. A device has been created and presented that allows for a simple measurement of the hardness of the varnish film on a pre-selected object of study, which was the insulating finger of the bracket of the brush holder of an electric locomotive traction motor. The process of measuring hardness and results for three groups of insulating fingers are presented: insulating fingers without coating by an impregnating compound (press material); impregnating material, sealed by convective method; impregnating material baked by thermoradiation method. On the basis of the obtained practical results, the effect of the energy supply on the curing process when performing drying by the convective and thermoradiation methods is explained. Also presented are photographs of an electrically insulating lacquer layer from an electron microscope, which allow the microstructure to be evaluated for the presence of gas inclusions, which have a negative effect on both mechanical and electrical indicators of polymeric insulation. A study was made of the relationship between the parameter of electrical and mechanical strength. On the basis of experimental data, the dependence of the breakdown voltage on the hardness of the insulating lacquer layer was constructed.

An analysis of the operation of electric locomotives on certain sections of railways shows that their power is used irrationally and electric locomotives are operated with low energy indicators, especially on long-distance flat stretches, which indicates that there are reserves for reducing the consumption of electric energy. The purpose of the work is to determine the optimal value of the rated power of electric locomotives by minimizing the electricity consumption on the site and to estimate the loss of electric energy from the non-optimal use of electric locomotives' power. To achieve this goal, an equation was drawn up for the dependence of the electric power consumption on the traction of an electric locomotive on the value of its rated power. To find the optimal value, this equation was differentiated by the value of the rated power of the electric locomotive and solved using the Cardano method. The expression allowed us to determine the minimum consumption of electric power is the rated power of the electric locomotive, depending on the required for a given traffic conditions and to evaluate the variation of energy consumption from non-optimal use of its structural capacity. The obtained equations allowed us to solve the problems of choosing the optimal value of the rated power of electric locomotives and evaluating the irrational consumption of electric energy from the non-optimal use of their power and can be used to determine the optimal parameters of electric locomotives. The conclusion is made about the importance of choosing the optimal power values of electric locomotives in order to obtain the highest technical and economic indicators during their operation.

The article suggests that the reason for the increased wear of the tires of electric locomotives with an asynchronous traction drive is the increased sliding speed in the contact of the wheels with the rails. It is shown that in thrust modes with high sliding speeds, frictional self-oscillations can develop in the drive. The stability zones of the drive are constructed in the space of its parameters. The model of an asynchronous drive with a «jammed rotor» for the study of skidding modes has been substantiated. It is recommended to install a clutch control system (СCS) on the electric locomotive to reduce wear on wheels and rails. СCS intelligent sensors create an additional feedback channel for the system of optimal traction control - the implementation of maximum traction forces with minimal friction losses. The methods and recommendations presented in the article are applicable to various designs of traction drives.

The analysis of the influence of operating modes and the development of the residual life, expressed through thermal wear of the insulation of the asynchronous traction motor. The research subject is to obtain new patterns of change in the residual life of the stator winding insulation, which make it possible to determine the specific life of the winding for each mode of the asynchronous traction motor. The research aim is to create a system for determining and assessing the residual life by developing methods and technical means of monitoring and comprehensive diagnostics, as well as theoretical justification using the method for determining additional thermal wear of the stator winding insulation, taking into account the combined effect of the starting transient process, the long-term allowable load schedule and the maximum allowable temperature values. To determine and assess the possible residual life, the method of sequential influence of starting transients, maximum permissible load curves, as well as long-term overloads at the maximum permissible temperature, taking place under various operating factors during the movement of electric rolling stock, was used. The expediency of determining the function of uneven resource development, which has a monotonic character and is approximated by a linear double exponential and exponential functions, is shown. Specific proportionality coefficients are experimentally determined, which characterize the decrease in the dielectric strength of the insulation with sequential alternation of maximum and long-term permissible loads and maximum permissible temperature values, followed by obtaining an analytical relationship that predetermines the insulation resource. It is shown that the determination and assessment of the residual resource under typical modes practically makes it possible to clarify the timing of preventive measures and predict the expected duration of accident-free operation and forestall the premature failure of the asynchronous traction motor.

The article is devoted to the improvement of the testing method of current collectors of electric rolling stock considering collision efforts from the overhead catenary. The article discusses the features of collision effects on pantographs of electric rolling stock at high speeds. An analysis of the existing methods for testing collision effects on pantographs in laboratory installations and in linear conditions has been carried out. The analysis is carried out and the drawbacks of the percussion pendulum installation for testing current collectors, described in GOST 32204-2013, are identified, and its characteristics are calculated. The design of a shock stand with smaller dimensions and expanded functionality is proposed, and its parameters and characteristics are calculated. When calculating the characteristics of the test bench, mathematical and computer modeling was applied using the MATLAB Simulink environment. The method of bench collision testing using accelerometers and high-speed video camera. It was established that the proposed test bench retains the full functionality of the test facility regulated by GOST, while having smaller dimensions and wider functionality.

The article discusses the thermal state of the disc brake elements during braking, taking into account the distribution of heat fluxes between the friction elements. The results of the study of the influence of the thermal resistance of the medium filling the microcontact gaps, caused by reversible deformations of the surface microgeometry, on the thermal state of the disc brake elements are presented. Method - the description of the thermal state of the disc brake elements during braking is made on the basis of the Fourier - Kirchhoff differential equation of thermal conductivity, taking into account the influence of the thermal resistance of the medium filling the microgaps between the surfaces of the brake pad and the brake disc. Results of the work: The calculation of the thermal state of a railway disc brake was carried out taking into account the reversible deformations of the microgeometry of the surfaces of the working elements of the disc brake. The exact dimensions and shape of the disc brake elements are specified in the CAD system (SolidWorks). The graphs of changes in the thermal energy generated and dissipated by the disc brake at different initial speed and duration of braking are given. The obtained dependences illustrate the process of heat energy dissipation into the environment. The inertia of the friction system of the disc brake in relation to the dissipation of the generated thermal energy during braking is shown. It has been shown that the distribution of heat fluxes between the working elements of a disc brake depends on the level of reversible deformations of the microgeometry of the brake disc surface, which directly determine the thermal resistance of the medium filling the microcontact gaps. Taking this circumstance into account makes it possible to increase the reliability of calculations of the generated and dissipated energy by the working elements of the disc brake during braking. The results of the study are recommended for use in calculating the thermal state of the working elements of the disc brake during braking.

The purpose of this article is to analyze the voltage drop in the contact network caused by poor-quality operation of an alternating current electric locomotive when passing heavy trains. Heavy-haul traffic is considered today as a valid and necessary tool for increasing weight norms and increasing the throughput of railway sections. The article provides statistics on the passage of heavy and connected trains on the Krasnoyarsk railway for 2019 and 2020. For the effective use of heavy traffic, it is necessary to solve a number of problems, one of which is to reduce the voltage in the overhead network when passing heavy trains, this negatively affects the speed of the train along the haul, the conditions for cooling the power equipment of the electric locomotive deteriorate, etc. As a result of the analysis of the operation of the thyristor rectifier-inverter converter, a number of disadvantages were revealed. The reason for the low power factor of the electric locomotive lies in the use of an outdated element base based on thyristors, their closure is carried out only in the next voltage half-cycle, long-term switching and a large opening angle of thyristors leads to a significant reactive current in the contact network. Based on the analysis the voltage losses at the current collector, it was concluded that it is necessary to reduce the duration of the switching process of the arms of the rectifier-inverter converter, in which a short circuit occurs in the secondary winding of the traction transformer. An alternative version of the converter based on fully controlled semiconductor devices - IGBT transistors is proposed. The ability to open and close at any time of such elements allows you to minimize the phase angle and increase the power factor. Due to the almost instantaneous switching of transistors, the distortion in the contact network is minimized.

The issue of optimizing the use of lubricants to reduce the in-intensity wear of the wheels of traction rolling stock is considered in the work. The purpose of the work and the test objects are defined. The types of tests, their procedure, short description of tests, and compliance with the technical assignment and technical requirements are presented. Design work was carried out on the development of solid antifriction elements for lubricating the ridges of locomotive wheel pairs (hereinafter referred to as TAEL rods). Bench tests were carried out on a universal friction machine 2168 UMT «Unitrib», which models the contact interaction of the wheel with the rail when applying solid lubricant to the wheel ridge. The linear wear rate of the lubricating element and the friction moment were determined. Explutation tests were carried out on the basis of traction rolling stock of the series VL80, 2TE25KM, ChME3. Such indicators as average intensity of development of cores of TAEL and lubricant cores and average intensity of wear of crests of wheels were defined. The results of laboratory bench-out and operational tests of TAEL rods were obtained in accordance with the order of admission of lubricating materials for wheel-rail contact for use in locomotive combs operated on the railways of the Russian Federation. Operational tests of traction rolling stock were carried out at the landfills of the North Caucasus, South-Eastern and Volga Railways. During the performance test period, the following indicators were monitored: assessment of the impact of TAEL on the wear of co-forest steam ridges, assessment of the actual resource of TAEL production, assessment of the functional capabilities of TAEL rods. According to the test results, the developed TAEL rods received permission to use Russian Railways for the infrastructure. At the same time, the wear rate of the ridges of the wheel pairs of locomotives equipped with TAEL in comparison with the standard rods decreased to 50 %.

Transportation in tank cars of viscous liquid cargo (fuel oil, paraffins, industrial oils, cracking residues, etc.) is difficult with their solidification, accompanied by a sharp increase in viscosity. In fact, this leads to the need to warm up or partially warm up the transported oil product before unloading, usually carried out as a gravity discharge, in order to restore the fluidity of the delivered oil cargo. The process of unloading in this case with heating leads to a significant increase in the cost of transporting petroleum products, including the downtime of tank cars, and in general, a decrease in the turnover of rolling stock. According to the analysis carried out to determine the costs of the technological process of heating frozen petroleum products transported by rail, about 600 thousand tons of conventional fuel are spent per year, and the idle time of tank cars under unloading and subsequent cleaning of boilers from high-viscosity residues of oil cargo exceeds 1 million car-hours. The urgency of the issue of reducing the cost of railway transportation of viscous cargo is due to the intensive development of the Northern and Eastern regions of the Russian Federation. Important factors for transportation in these conditions are not only the negative average daily air temperature, but also long distances. The issue of reducing the cost of transportation of viscous petroleum products at low air temperatures is considered. Viscous petroleum products, when thickened, turn into a rheological liquid, which does not have a clear interface between the liquid and solid phases. The methods of transfer to the stratified state of hot fuel oil during its slow cooling and partial solidification with the formation of a heat-insulating layer of solidified fuel oil are applied. The positive effect is achieved by reducing the time and cost of thermal energy for unloading the delivered oil product by reducing the rate of its cooling during transportation. This, in turn, is achieved by suppressing the natural convection of the hot oil product on the cold walls of the boiler of the tank car in the first few hours after filling the tank. From the comparison of the experimental data and the calculation results, the values of the empirical coefficients of the equation for the heat transfer coefficient of liquid petroleum products are selected. The standard deviation of the absolute temperature of the liquid petroleum product was 8 %.

At this time the traction electric motor (TEM) is one of the most important elements of the design of rolling stock, since the safety and stability of the transportation process on the railway network of JSC "Russian Railways" depends on its uninterrupted operation. This article is given a detailed analysis of the TEM failures of diesel locomotives of the 2,3TE10 v / series and the assigned fleet of the Novaya Chara locomotive depot of the East Siberian Traction Directorate. The section of circulation of diesel locomotives from Taksimo station to Hani station is one of the most difficult not only in the borders The East Siberian Railway, but also the entire railway network of the country. The analysis of the statistics of the reasons for the failures of the TEM of locomotives of the Novaya Chara locomotive depot for 2006 - 2012 showed that there is a rather extreme operation mode and that most of the failures are due to the breakdown of the insulation of the anchor winding of the TEM. During a research trip to the diesel locomotive maintenance site, a team of IRGUPSA scientists conducted full-scale measurements speed of movement, driving mode of the train, heating temperature of the TEM, taken into account the climate factors - ambient temperature, relative humidity, pressure and others. After studying the available information, it was proposed to additionally coat the insulation with FL-98 varnish in order to maintain and restore its properties in the conditions of the Winter locomotive depot during TR-3. IRGUPS has been working for a long time to study the process of drying insulation using infrared radiation (IR). The effectiveness of this method has been proven by numerous experimental studies. Several PhD theses have already been defended in various dissertation councils on this topic. This article presents also the statistics of failures of operated TEM already with additional varnish-impregnated insulation of open frontal parts after the implementation of measures based on the results of the work of the IRGUPS group of scientists. It is established that the method of applying the compound to the insulation of the frontal part of the windings of electric machines and encapsulating it with the help of IR radiation energy is effective in combating TEM failures due to insulation breakdown.

Special attention on the Belarusian Railway is paid to the issues of operation of curved-linear sections of the track, since in the framework of solving the problem of increasing train speeds; one of the significant obstacles to changing the speed regime is the discrepancy between the actual position of the curve of the project documentation. The automated systems of mobile diagnostic tools used on the road fully allow us to evaluate the actual parameters of the curves, which can form the basis for modeling the desired positions of the curves for the purpose of their certification. For this purpose, various orders and orders are drawn up annually, which set the main parameters of the curves in the plan and level, as well as the volume of work on the reconstruction (modernization) of the curves in order to bring them to the project documentation. In the Methodology introduced at the Belarusian Railways for evaluating the actual parameters of the installation of curves of track sections, general provisions given for the regulations that determine the procedure for performing actions when performing qualitative and quantitative assessments of the parameters of the geometry of the rail track. Depending on the state of the actual parameters, it is assumed that the curve will be assigned a certain status, which determines the order of its further operation, and depending on the ratio of the actual parameters relative to the design parameters, the degree of violation. The parametric analysis of this technique allowed us to generalize the results of structural, functional and informational analyses of the order of assessment of the level of disorder of curves, with assigning them the appropriate status, and the value of indicators that determine the degree of violation. The study of the parameters of curved sections revealed discrepancies in the qualitative and quantitative estimates of the same track sections, as well as the need for a comprehensive assessment of the actual and design parameters of the rail gauge geometry.

Purpose. Constructing a model for predicting a quantitative indicator of the pre-discharge state of the upper structure of the track based on a statistical analysis of the seasonal dynamics of this indicator. Forecasting involves identifying bottlenecks for timely corrective action. This approach allows you to refine the construction of algorithms of the functional risk assessment system on the infrastructure of Russian Railways for managing the technical condition of the railway track and safety and is considered as an element of digitalization of the risk assessment of traffic safety in the Railway Infrastructure Directorate. The development is carried out on the basis of accepted existing regulatory documents and classifiers of risk factors operating for the infrastructure management at Russian Railways. Methods. regression analysis, data validation, modeling based on regression analysis. Results. Dependence was identified and a forecast model of the dynamics of the number of deviations of the 2nd degree rail gauge geometry (GRK) was built based on the use of actual data from the automated system Path (APCS P) of Russian Railways. Testing of the approach was carried out on the basis of the Directorate of Infrastructure of the North Caucasus Railway. The identified dependence allows you to give a fairly accurate forecast of the state of traffic safety and the development of GRK deviations on the 2nd degree for use in practice, effective planning of material costs for planned preventive work and overhaul at linear enterprises, on a specific railway adopted for calculation and on the network of Russian Railways. Practical significance. The constructed model allows predicting the intensity of the risk factor on an objective basis of seasonal patterns, as well as the volume of control impacts on the current content of the upper track structure. The presence of such a forecast will make it possible to establish a relationship between the indicator of the dynamics of the number of deviations of the 2nd degree rail gauge geometry, including seasonal dynamics, and the risk factor, that is, the number of GRK deviations of the 3rd degree used in the risk assessment on the infrastructure. The result of this approach is the solution of a system of tasks that affect the values that reflect the level of risks, and as a result, effective management of financial flows for the maintenance of infrastructure, reduction and prevention of traffic safety incidents.

The integration of the railways of South and North Korea will make it possible to form an international Eurasian transport corridor and ensure the transportation of goods produced in the Republic of Korea by rail. Today, South Korean cargo owners, due to the island situation, use mainly sea transport. The organization of transportation on the Trans-Korean Railway with access to the Trans-Siberian Railway and the railways of China and Mongolia will give advantages to shippers in terms of cost and time of cargo delivery. The implementation of the project on the reunification of the Trans-Korean Railway will lead to an increase in the volume of cargo and container transportation, including in rail-sea communication. In the Republic of Korea, the main transport hub is the port of Busan, which is served by rail and road transport. The Busan transport hub includes two seaports - the new and old Busan ports, railway stations serving the container terminals of the port, as well as rear terminals to which container delivery is carried out by road. Every year, the share of rail transport for the import and export of containers to the terminals of the port of Busan is less than 7 % and continues to decrease. This dynamic is associated with the presence of infrastructure, economic and technological problems of interaction between rail and sea transport in the port of Busan. The subject of this study is the analysis of the processes of interaction between different modes of transport in the new port of Busan. The purpose of the work is to develop measures to increase the capacity of the railway component of the Busan transport hub for the organization of trans-Korean transport within the framework of the Eurasian transport system. In this paper we used theoretical methods of research, including a systematic analysis and synthesis of information. As a result of the analysis of the technical equipment, operating technology and the existing railway infrastructure of the New Port of Busan, the presence of «bottlenecks» in the functioning of the «railway - seaport» system was revealed, which hinder the effective process of container transportation. The paper considers infrastructure, technological and organizational measures to increase the processing capacity of Busan transport hub facilities. The implementation of the measures under consideration will require time to change and restructure the system of interaction of transport in the process of container transshipment. It is necessary to determine the stages of infrastructure changes based on the forecast of future traffic volumes, including using simulation modeling.

The article deals with the application and use of heat pump installations as a low-potential source of heat energy to provide consumers with heat energy in the building heating system. Today, one of the most environmentally friendly and economical alternative sources of thermal energy is a heat pump unit. The use of these devices will reduce COemissions. The main advantages and disadvantages that appear during the operation of heat pumps are listed. Based on the results of tests of boilers using organic fuels (coal, fuel oil, natural gas)and low-potential heat sources with an electric drive, the dependences of the heat transformation coefficient of the heat pump and the efficiency of boilers operating on organic fuels on the cost of conventional fuel per unit of released energy are constructed. The coefficient of heat transformation of heat pump installations in the range of changes in operating parameters 3,0 < µ < 5,0 is determined. A graph of the dependence of the energy conversion coefficient on the temperature of the heat carrier in the heating system and the ambient temperature is constructed. A schematic diagram of the connection of a heat pump installation to the building heating system is proposed. Studies were conducted in the period from April 1 to April 21, 2021 in the laboratory auditorium of the educational building of OmGUPSa and the readings of the main parameters of the operation of the heat pump unit with the Vitocal 242-S heat pump were recorded. Based on the results of the main parameters, the following are calculated: the thermal load on the room heating system; the temperature of the coolant in the supply pipeline; the amount of electricity consumed by the heat pump; the conversion coefficient of the COР. The optimal values for this heat pump unit under the specified operating modes are estimated.

Station radio communication is an integral part of the technical means involved in the organization of a safe transportation process. Increasing the signal power in places with a complex electromagnetic environment remains an urgent issue. A passive repeater can serve as a solution to this issue, therefore the purpose of this work is to test the possibility of increasing the signal power level using a passive repeater.The article provides an analysis of a passive repeater used as a device that improves the quality of radio communications in places with a difficult electromagnetic environment. The differences between the use of a passive repeater and active relay stations are given.An analysis of the existing methods for calculating the parameters of passive repeaters was carried out, on their basis, modeling and calculation of the parameters of a passive repeater were carried out for the development and conduct of research in real conditions at a railway station. The design, materials of manufacture of the passive repeater, as well as the measurement scheme in real conditions are presented.The study is based on theoretical calculations and performance checks in real conditions and comparison of the results obtained. As a result of the study, it was found that the use of a passive repeater in a complex electromagnetic environment makes it possible to increase the signal power level, thereby increasing the stability of radio communication.It was noted that it is necessary to refine the existing method for calculating a passive repeater, since the above technique was used when calculating passive repeaters over long distances. A variant of fastening passive repeaters without the development and installation of additional new structures is proposed, the need to organize further protection against overvoltage is indicated.The results obtained will be useful in the development of new radio relay communication lines and the modernization of existing ones for places with a difficult electromagnetic environment and rough terrain.