Journal of Transsib Railway Studies V.2(46), 2021

He method of researching the dynamic properties of the railway crew in the action on it harmonic parametric perturbation, caused by the changing rigidity of the base of the rail, is set out. For such differential equations there are no regular methods of solving them, moreover, their exact solutions are not known at present, so they are used by approaching methods. A two-degree mechanical system with a harmonic parametric perturbation described by a system of ordinary homogeneous differential equations is considered. One of the hard-bone parameters is a function of time and varies from 2000 to 3000 N/m. To calculate the boundaries of dynamic instability (parametric resonance) a method of generalized Hill definers is used, which does not require the introduction of small parameters. The area of interaction of parametrically excited and forced vibrations has been determined.

The purpose of this work is to determine the causes of cracks in the frame of traction motors of electric locomotives. An analysis of the statistics of detecting cracks in the frame of NB-514 traction motors at the Eastern testing area is presented, showing that every third frame in operation has cracks. The method of mathematical modeling on a computer with the use of FEM was used. It is noted that carrying out measurements in the crack initiation zone by the tensometric method is practically impossible due to the geometry of the frame. The results of mathematical modeling of mechanical stresses arising in the frame of the NB-514 traction motor during its uneven heating to temperatures characteristic of the hourly mode of operation of the traction motor are considered. It is shown that mechanical stresses arising only due to the temperature difference between the ambient air and the windings of the main and additional poles of the traction motor can reach 100 MPa. Variants of changing the design of the ventilation windows of the frame are proposed to reduce the magnitude of temperature stresses with a constant area of the ventilation openings. When correcting the shape of the ventilation windows of the traction motor frame, these voltages can be reduced to 76 MPa. It was concluded that one of the main reasons for the formation of cracks in the frame of traction motors are cyclically repeating temperature stresses, which is especially important for electric locomotives operating on mountain pass sections in the pushing mode. It is noted that the appearance of mechanical stresses in the backbone of the traction motor also depends on vibrations arising from the path and operation of the gear train, as well as on the variable part of the magnetic field of the motor, which are not currently studied in detail.

Measures to normalize the consumption of diesel fuel for the operation of shunting locomotives are an integral part of the efficiency of the use of traction rolling stock. Due to the presence of problems in the formation of the fuel consumption rate, such as the performance of the shunting locomotive, the loading and technical condition of the diesel generator set, the operating conditions of locomotives, it is necessary to improve the existing fuel consumption rate determining methodology. The article presents the results of studies of the operating modes of shunting locomotives, the parameters of the spread of the values of the operating time of the diesel generator set in the load mode for shunting locomotives of the TEM2 and TEM18DM series are given. A mathematical model based on the bases of machine learning models is proposed, taking into account the degree of loading of the diesel generator set and the technical and economic characteristics of the locomotive series. The task of the proposed model is to determine the fuel consumption of a locomotive by an iterative calculation method, where the input parameters of the model are the performance indicators of the locomotive. It is established that the method of forming the fuel consumption rate for performing shunting operations should take into account the degree of loading of the diesel generator set and the technical and economic characteristics of the locomotive series. According to the results of the implementation of the proposed model for establishing specific fuel consumption rates for the studied locomotives based on the results of their operation, the average indicators of specific fuel consumption by locomotives by the positions of the driver's controller are obtained. The proposed method allows us to take into account the actual degree of loading of the diesel generator set and establish the correct fuel consumption rate for a certain period of operation of the locomotive, which represents the practical significance of the work. The presented research results are the beginning of work on the development of an intelligent system for diesel fuel rate rationing for the operation of shunting locomotives.

The work relates to the application of a new method of noncontact RFID monitoring of the condition of insulators for overhead power lines, including signaling, centralizing, blocking, and longitudinal power supply lines . A significant number of accidents occur due to the breakdown of insulators and imperfection of control methods. It is proposed to use a non-contact RFID control system for overhead power line insulators, which consists of a reader with a transceiver and an antenna, standard insulators with RFID indicators and special software. The aim of the research is the influence of climatic factors on the components and assembly structures of pin insulators with RFID indicators and the operation of the RFID control system in general. The selected study samples are a radio frequency tag, an aluminum-coated plastic cap with an integrated tag, and a pin-shaped porcelain insulator with an RFID indicator in the assembly. The climatic tests were carried out in the testing center of technical means of railway transport of the Ural State University of Railway Transport (IC TSZHT USUPS). Temperature changes were simulated from -60 to +50 ° С with air humidity up to 93%. The results on the adhesive properties and electrical conductivity of a conductive coating on a polyethylene surface and the stability of the functioning of RFID tags are presented and analyzed. Suggestions for improving the components and assembly design are given. Firstly, to use a screw thread on the top of the pin instead of a special knurling, which will reduce mechanical stress during installation of the structure of individual components and will reduce the error in the installation dimensions to improve the reception and transmission of signals between the reader and the tag. Secondly, sandblasting of the surface of the polyethylene cap can improve the adhesion of the surface to the conductive coating, which will increase the electrical conductivity of the structure. The result of this work proves that the developed RFID control system of insulators functions in the climatic conditions specified by GOST, which allows to recommend its implementation in the lines ts use in lines of devices with a voltage of 6-10 and 35 kV.

The drawbacks of the step-by-step automatic voltage control system under load AVC and the non-contact automatic voltage control system NAVC with the reactor switching device of the converter transformer used in the traction power supply are analyzed. The scheme of a thyristor-reactor switching device (TRSD) connected to the primary winding of the transformer is considered. A brief description of the operation of a transformer with TRSD and the procedure for calculating the symmetrical and asymmetrical external natural characteristics of a converter unit with TRSD are given. Based on the dependence of the energy indicators of the converter unit on the resistance of the uncontrolled reactor TRSD, a method is proposed for calculating the rational resistance of an uncontrolled reactor, where the power factor of the converter unit is taken as the criterion of rationality. The method includes two stages: the first is the calculation of the values of the power factor of the converter unit depending on the resistance of the uncontrolled reactor and the load current of the converter unit; the second is the determination of the average load current value of the power factor of the converter unit for each considered value of the resistance of the uncontrolled TRSD reactor and the determination of the rational for the considered external natural characteristics of the unit. In accordance with the presented methodology, the calculation of the minimum permissible and rational resistances of the uncontrolled reactor TRSD as part of a converter unit with a converter transformer TRDP-16000/10 was made. Taking into account the selected rational value of the resistance of the uncontrolled reactor TRSD, a calculation was made and the external natural characteristics of a converter unit with a TRSD and a converter transformer TRDP-16000/10 are presented. The performance check of the presented calculation method for solving the problem of choosing the rational resistance of an uncontrolled reactor was carried out on a physical model of a converter unit with a TRSD, with a 12-pulse rectifier unit, with a 30 kVA transformer and a linear primary voltage of 380 V. Comparison of experimental and calculated values showed a slight discrepancy, the permissible error was not exceeded. Determination of the resistance value of an uncontrolled reactor based on the developed methodology provides the highest values of the power factor of the converter unit.

The article deals with the organization of operation when using cryogenic technologies for gas locomotives and isothermal cars (IV). The structure of transportation of perishable goods (SPG) by types of rolling stock and types of cargo and the peculiarities of transportation of frozen fish from the Far East to the central regions of the country is presented. On the example of their consideration, a new structure of the type of isothermal rolling stock (IPS) is proposed, including various types of single isothermal cars, large-capacity refrigerated containers and swap bodies. It is proposed to use the block-modular principle of forming energy refrigeration equipment for promising autonomous refrigerated cars (ARC). A review of promising ARC models developed by UralVagonZavod and Altayvagon, ready for serial production, has been carried out. The factors that should be taken into account when creating an innovative isothermal rolling stock are formulated. Variants of using cryogenic technologies for an autonomous refrigerator car and single insulated cars are considered. Based on the results of previously conducted operational tests of autonomous liquid nitrogen cars, the main their advantages and possible areas of use are given. The technology and technical solutions for improving the design of the cooling system of the cargo space for thermos cars cooled with liquid nitrogen have been substantiated. The calculated characteristics of the consumption of liquid nitrogen during the transportation of frozen goods are presented. The advantages of using environmentally friendly liquid nitrogen cooling systems are analyzed and the areas of using cryogenic technologies for isothermal rolling stock are formalized. Uncertainty and spontaneity of the perishable goods transportation market, along with the absence of a large customer, poses a difficult task for car builders to organize serial production of isothermal rolling stock with small production volumes and various technical characteristics. Therefore, when creating isothermal and refrigerator cars, it is advisable to focus on a single universal car kit based on an isothermal body with the possibility of transforming it by using various options for energy refrigeration equipment and chassis.

The article discusses the criteria used to calculate the probability of failures of devices of the current collection system due to ice and frost deposits on a catenary. The purpose of the work is to determine the influence of climatic and operational factors (including the number of vibrating pantographs, pneumatic drums on electric locomotives within the boundaries of the Directorate for power supply and devices for mechanical cleaning of ice at power supply distances) on the probability of the occurrence of failures of the current collection system and their severity, which will allow to increase the reliability of operation of traction power supply devices in conditions of ice formation and the efficiency of investments by Transenergo and the Traction Directorate for the purchase of these funds. To determine the likelihood of failures of current collection devices due to the formation of ice on the wires of the contact network, it is proposed to divide all factors into climatic and operational. The choice of factors in predicting failures was carried out using a probabilistic Bayesian network based on statistical methods of data processing, as well as correlation and regression analysis. As a result of the research, the factors influencing the likelihood of failures of current collection devices have been determined, and their significance has been assessed using the calculated variances. A method is given for calculating the probability of failure for a conditional distance of power supply, which makes it possible to assess the adequacy of the equipment of Transenergo and Traction Directorates with devices for mechanical cleaning of ice from a contact wire, vibropantographs and pneumatic drums.

The article discusses the possibility of extending the service life of passenger cars. The analysis of the state of the passenger car fleet has established that the rate of replenishment of reserved cars has been reduced by more than 40 % over the past 10 years, therefore, it is possible to ensure coverage and replenishment of the retirement of rolling stock of this type after the expiration of the standard service life only by extending the service life of existing cars by carrying out capital repairs with the establishment of a new standard service life. When analyzing the power frame of a reserved seat passenger car, it was found that the greatest static and dynamic loads are perceived by its center beam. It is precisely because of the stresses arising in it that an assessment is formed of the further possibility of operating a car both during its life cycle and further use in diagnostics for the possibility of assigning a new service life to it during overhaul repairs. Studies of a number of elements of center beams cut from passenger cars that have expired the standard period have established that the main characteristics of the metal meet the requirements of safety standards, this indicates that the safety margin and resource inherent in them has not been fully depleted. In the study of the presence of residual stresses that have arisen in the elements cut from the ridge beams, depending on the depth of etching carried out according to the method of N. N. Davidenkov in accordance with the TSNIITmash methodology, the most vulnerable and dangerous places of corrosion that require more careful control during the car maintenance and scheduled preventive repairs were identified. In order to reduce the development of residual stresses and the corrosive effect on the load-bearing frame of a second-class car, recommendations and technological operations have been developed for strengthening the ridge beam by the method of shot-blasting with the formation of a uniform fine-pored structure, which ensures uniform application of paint and varnish coating.

In this article, the problem of assessing the stability of a continuous welded rail track during its thermal elongation is considered. The article considers the method of determining a stress-strain state of continuous welded rails proposed by specialists of JSC “VNIKTI”, which is based on the use of the dependence of natural frequencies of rail vibrations on the applied longitudinal force. Such a dependence can be obtained with the help of the calculation method using a finite element model of a track section. The reliability of such a dependence can be assessed by comparing the results obtained using the calculation method with the actual values of natural frequencies of rail vibrations, depending on the longitudinal tensile and compression force applied to a full-scale facility. The track panel is chosen as such a facility. In order to obtain the actual dependence of natural frequencies of rail vibrations on the applied longitudinal force, a specialized test bench is developed. The development of the test bench included designing the test bench elements and creating finite element models of main load-bearing elements of the test bench - a stop, support and traction, as well as their subsequent strength calculation to confirm the operability of the selected design under necessary loading conditions. The strength is assessed using the safety factor for the yield strength. Calculations using the finite element method have shown that the test bench design has sufficient strength. The developed test bench will allow performing tests for the purpose of the verification obtained using the calculation method of the dependence of rail vibration frequencies on the longitudinal tension and compression force applied to it, as well as for testing the proposed method to assess the rail longitudinal force during its thermal expansion.

The article deals with the possibility of applying diagnostic algorithms, taking into account the complexity of the examination, applied to a specific problem of searching for damage in receiver end of station's tonal track circuit. The article presents calculated conditional probabilities, diagnostic weights, particular and general diagnostic values of examinations, taking into account the time of movement and work by an electrician. Based on the calculations performed, a conditional diagnostic algorithm has been compiled, taking into account the complexity of the following for the equipment of the relay end of the tonal rail circuit. The effect of using this algorithm is shown. The results of the work given in the article can be used in the maintenance of automation systems of existing railways.

The main engineering problem associated with the degradation of permafrost and cyclic freezing-thawing of seasonal permafrost soils is a decrease in the bearing capacity of engineering structures due to the degradation of the main physical-mechanical properties of the embankment soils. The cyclical change in temperature leads to regular freezing-thawing of the soil, as a result of which such types of deformations occur as heaving during freezing and settlement during thawing. The purpose of this work is to highlight new information about complex measures to stabilize the subgrade of railways and highways in the cold regions of China. The paper considers such measures as thermosiphon stabilization, rock fill, installation of ventilation pipes and laying of thermal insulation boards. This paper also describes the disadvantages of existing measures for stabilizing the temperature regime of the embankment and its base. Considered the main transport network of the Qinghai-Tibet plateau, including the Qinghai-Tibet railway and four highways. The experimental section of the Wushu-Xining expressway on the Qinghai-Tibet plateau was chosen as the object of the study of numerical modeling; a numerical calculation of the temperature and moisture content fields of the typical embankment was carried out, as well as numerical calculation of the embankment with rock fill for the 10th year of operation. The calculations were carried out on the basis of the «Freeze-Cold» software package specially developed for engineering calculations of the freezing and thawing process in soils. The calculation showed that rock fill allows to reduce the area of the soil thawing, raising the front of frozen soil, helps to reduce the degradation of frozen soil, which ultimately has a positive effect on the bearing capacity of the entire engineering structure. Analysis of the collected data and calculated values allows to conclude that the use of rock fill of 0,8 meters depth as an insulating material to maintain the stability of the thermal regime of the embankment on frozen ground in the considered region of the Qinghai-Tibet Plateau.

The purpose of the work is to analyze and assess the structure of economic development and the impact of the «economic space» on railway transport in Uzbekistan, to consider the use of container block train technology. Scientific methods of analysis and synthesis, classification, mathematical statistics, economic analysis, mathematical technical modeling are used. The following results were obtained. The dynamics of the development of cargo transportation in Uzbekistan is assessed on the basis of GDP data. The volume of provided transportation and the use of modes of transport by the volume of shipped products is considered. Of these, the number of goods shipped in Uzbekistan from railway transport, the dynamics of the volume of transportation of certain types of cargo in containers. According to the dynamics of the growth of cargo transportation, a decrease in growth was revealed in 2020 and associated with the pandemic, but in general there are steady growth rates. It is concluded that along with the ongoing work on the renovation and reconstruction of railway tracks, it is necessary to take measures to optimize the entire chain of cargo transportation by containerization, so the use of block train technology. The practical significance of the results of the study follows from the fact that the analysis of the development of transport infrastructure revealed a sharp decline in the results of transport at the end of 2019 - 2020 due to the pandemic, but at the same time, there is a reduction in the «economic space» by improving transport infrastructure, simplifying transit and customs clearance procedures, increasing transit volumes and regional trade, therefore, the logistics transportation market in the republic will grow at an accelerated pace in the coming years. Mass use of containers with the use of block train technology, so. the collection of containers from the port rear terminals, where the formation of batches of containers takes place, and their accumulation in the volumes required by the buyer for transportation by rail can also be a solution to the identified problems.

In the article, on the basis of the thermodynamic analysis of the working process in the turbine, a method is presented for determining the generation of electricity based on heat consumption and an assumption is made about the possibility of instrumental measurement of the amount of generation and the implementation of accounting in real operating conditions of the steam turbine. This indicator can become an important indicator in the district heating system and automatic regulation of heat energy supply, such a statement of the problem in the district heating system was made for the first time and requires additional research. The article discusses the influence of electricity generation on thermal consumption on the efficiency of the power system of district heating. Dependences of electricity generation based on heat consumption on the share of steam supplied to the heating extraction are obtained. Specific power generation has been determined taking into account regeneration.

To improve the accuracy of the diagnosis of the technical condition of rolling stock, it is necessary to develop new algorithms for the digital processing of signals coming from sensors at the time of the passage of the axes of wheeled pairs of wagon carts during the uniform movement of the train on the straight section of the railway track. The use of modern mathematical application software packages to model digital-based data processing algorithms reduces the cost and time of developing automated systems to diagnose the technical condition of the rolling stock of railways. To assess the accuracy of the fixation by the magneto-induction sensor of the moment of passage of wheel pairs axly, an asthigmatic model is proposed, allowing to investigate not only the energy properties of the sensor, but also the shape of the output signal, taking into account the real dimensions of its magnetic core. The developed model allows you to classify the pore. The developed model allows to classify the order of astigmatism model magnetoinduction sensor based on a set of discrete virtual sensors