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In the article there is the increase of rail circuits work stability in conditions of heavyweight traffic for AC traction sections. There is a coordinate plane graph of backward traction circuit base diagnostic states in the paper. We analyzed the results gained in the researching and suggested the way to coordinate rail shunt location and to evaluate the insulation resistance in backward traction circuit.

In article the possibilities of decrease in energy consumption on draft at the movement of electric trains in the conditions of a flat profile of West Siberian Railway due to shutdown of traction section of an electric train and rational distribution of time of the course in all direction of the movement are considered. During the calculating and creation of schedules of the train for site is used an analytical method of the solution of the differential equation of the movement of the train. For the analysis of optimum schedules of the train at each stage of their modeling an inspection of calculations which allows to guarantee reliability of the received results is car-ried out. For definition of potential opportunities of decrease in energy consumption on draft at traffic control of an electric train the concrete trip of an electric train of ED4M along a route Omsk - Irtyshskaya is analysed. Settlement schedules of an electric train are provided in the considered trip, and also with shutdown of one traction section. Average is defined by standard means of system of computer modeling on the way the electric train speed, dispersion of speed on the way, energy consumption. The received size of energy consumption for draft with the disconnected traction section is much less than energy consumption on a real trip. Rational distribution of time of the course of the electric train in all direction of movement from a condition of preserving time of its arrival also allows to reduce an electric power expense on draft by the terminal station. Based on consumption data of the electric power in general possible economy of energy costs on draft due to application of the offered methods is determined by Omsk TCh-31 depot.

The article presents the results of a study of the effect of the functional relationship between the parameters of the microgeometry of the brake disc surface and the level of the stress-strain state of the contact area on the thermal resistance coefficient. The results of an experimental study of the process of changing the step and altitude parameters of the microgeometry of the surface of the brake disc under the influence of normal and tangential forces realized during friction are obtained. It was found that under the influence of normal and tangential forces, the height parameters of the microgeometry tend to increase, and the step parameters tend to decrease. It is shown that when calculating the contact thermal resistance, it is necessary to take into account the functional relationship between the geometric parameters of the microroughness of the brake disc surface and the level of the stress-strain state of the contact area. The calculations performed without taking into account this connection lead to overestimated values of the contact thermal resistance and, accordingly, to errors in determining the values of heat fluxes passing through the contact area of the mating surfaces. The values of the constants, which depend on the design features of the friction unit of the disc brake and are used to determine the nature of the change in the geometric features of microroughnesses, have been specified. The correction of the input parameters of the microgeometry of the surface of the brake disc is performed, taking into account the dynamics of changes in their geometry under the influence of force loading. It is shown that it is advisable to take into account the dynamics of changes in the surface microgeometry in the analytical determination of the contact thermal resistance of a disc brake. The results obtained are recommended to be used in calculating the friction characteristics and assessing the heat fluxes passing through the area of mutual contact of the brake disc and brake pads of the disc brake.

The article is devoted to the research of the of wind load effect on the aerodynamic component to the movement of a freight train. These findings contribute to a better understanding of the impact of aerodynamic resistance on the consumption of fuel and energy resources (FER) on train traction. The article shows the high significance of this problem for Joint Stock Company Russian Railways (RZD JSC). The conclusions were drawn from the analysis of statistical data on the routes of locomotive drivers, working on the Pallasovka-Verkhniy Baskunchak section, which is undergone to wind loads. The SOLIDWORKS application was used to design a train with a locomotive and gondola cars coupled on an embankment, and SOLIDWORKS Flow Simulation plug-in was used to simulate wind load, different in speed, varying from 0 to 90º. The values of the force of aerodynamic resistance to movement for the train as a whole and for each unit of the rolling stock separately were obtained. Using the methods of the theory of train traction, the influence of aerodynamic drag on fuel consumption for traction has been assessed. Based on the obtained values of the aerodynamic drag forces and patterns of air flow distribution, conclusions were drawn about the effect of loading a gondola car on an increase in traffic resistance. Conclusions are drawn about the effect of wind load on each unit of rolling stock in the train. It was found that when the wind is directed at an angle to the axis of the path, the force of the wind effect increases, compared with the case when the angle between the axis of the path and the velocity vector is zero. The experimental data on the increase in resistance from the wind load are confirmed by theoretical calculation, as well as practical processing of routes machinists. This article demonstrates the need for a separate regulation of fuel and energy resources in the event of wind loads, and may be useful in further detailed study of the aerodynamic drag of freight trains.

In this article, the object of the study is the power supply cables for non-traction railway consumers. The electrical parameters of the insulated conductor are determined. Primary parameters of the aluminum shell of the main power supply cable are obtained. As a result of solving the problem, the transient resistance of an isolated conductor is determined. From the boundary conditions, the propagation constant of the metal shell of the power supply cable in the polymer insulating coating is determined. As a result, the values of the transition resistance obtained by different methods are the same.

Article is devoted to one of actual problems – to definition of the rational hardness ratio of wheel and rail. The mathematical model of wear process of friction pair «wheel – rail» is developed. Results of researches on intensity of wear process of wheel and rail are presented.

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.

In the article the finite element model of the electrical contact pin wire - collector strip, which takes into account the complex interaction of electric and thermal processes. As the contact wire is selected worn MF-100, the current collection plate - two brands VJZ-metal and graphite. Microgeometry the body surface at the contact point is obtained based on the model of Greenwood - Williamson. It was considered the two extreme cases of possible contact between the contact wire to the plate. The results were analyzed and compared with the known experimental data. Calculated at what proportions contact force and contact current due to burnout occurs spark or arc. Identify ways to improve the model.

Article is devoted to actual questions of research of microstructure,physic-mechanical and tribological indicators blankets of friction couple "ring-sleeve of cylinder" under laser processing.Analysis of base defects of elements of cylinder-piston group of internal combustion engines,methods their reduction and rise of tribotechnical characteristics are conducted.Notes that different kinds of thermos and chemical thermal processing of working surface of link are most effective means of rise of wear resistance of couple "ring-sleeve of cylinder".Using of perspective technology of laser thermostrengthening is offered with this target.Offering technologies find greater application in automobile and technics of agricultural purpose. But purpose of ICE in aviation industry due to their specific exploitative and specific design features is limited.At the same time,they may have important practical meaning. Different variants of laser modification of surfaces of coupling in the context of CPG of aviation engine of ASH-62IR are offered and analyzed in article. Data of microstructural analysis of blanket,indicators of microhardness and wear resistance are adduced.Short description of tribotechnical laboratory-scale plant and methodic of conduct an experiment on base of comparative analysis of findings is given.Wherein tribotechnical indicators are compared with results of metallographical researches and physic-mechanical properties of modification layer,in particular with indicator of microhardness. Conduct of tribological researches determines that rise of indicator of wear resistance of friction couple "ring-sleeve of cylinder" observed at all researching regimes of laser effect with acconting of identified border conditions of processing for both elements of coupling.Maximum value of wear resistance is observed at laser thermostrengthening of both surfaces of couple on critical levels of density of laser energy.These levels do not case of appearance of microcracks in blanket.Wherein wearing qualities of modification surface of cylinder sleeve may increase by 4,5 - 5 times and wearing qualities of piston rings more than 3 times. Theoretical bases of mechanism of wear of thermos thermostrengthening surfaces which illustrate kinetics of increase their wear resistance in result of formation of microstructure of special blanket with increased bearing capacity,microhardness and improved conditions of wear of modification layer.Experimentally validated that the greatest wear resistance is observed in the friction elements at their mutual modifying their surfaces.

The question of the possibility of using concrete foundations support of a contact network as earthing. The analysis of the impact of the construction of the foundation for the spreading re-sistance. The results of the calculation of spreading resistance of the anchor bolt foundation metal support on the proposed formula.

The article presents a method of the additional resistance calculating of ground grid drainage unit. This work has two main objectives: development of algorithm for determining the optimal values of additional resistance and to study the possibility of reducing losses in reverse traction network through drainage unit of traction substation. The calculation is carried out with a view to ensuring the normative values of the protective potential on the grounding grid and minimize losses in the reverse traction network. The method is based on the application of the reciprocity theorem, which allows to change the direction of the currents from the source to the load on the reverse one if the system is linear. The calculation of the values of additional resistance and power loss in the reverse traction network for average current on the considered traction substation of the Western-Siberian railway. In results the selection method of optimal values for the additional resistance is offered. This method can be used for designing of traction substation grounding grid protection.

This article discusses the problem of loss of elastic properties of Pandrol Fastclip rail fasteners during operation. The research is related to predicting the dynamics of changes in the elastic properties of the Pandrol Fastclip clamping terminals during their long-term operation and provides for the creation of control methods (regulation) by pressing the fastening terminals on the sole of the rails, which guarantees the safety of trains with set speeds. On the basis of the conducted research, the design of a device that increases the pressing force of the fastening terminals on the sole of the rails has been developed. This device will provide optimal parameters for attaching rails to the sub-rail base at all stages of railway track operation. At the same time, there will be no need to replace the expensive imported elastic terminals of the Pandrol Fastclip fastening in cases of a decrease in the elasticity of the terminals in the current path. The research results are relevant for dozens of foreign railways where modifications of the Pandrol Fastclip fastener are operated: Pandrol Fastclip FC, Pandrol Fastclip FCA, Pandrol Fastclip FE, Pandrol 350, Pandrol SFC, Pandrol 1520, etc. The proposed technology for carrying out work to improve the technical condition of the intermediate rail fastening structure will not require the provision of "windows" in train schedules, which will not affect the carrying capacity and capacity of the railway track and will not affect the delays of scheduled trains.

Recently, during overhaul of the railway track using modern materials such as geotextiles and penoplex. In turn, they make significant changes to the structure of the ballast, t. To. Are almost insulators. OSTU experimentally it has been ascertained that the contact resistance in the case of using a new type of cloth can be raised to 45 - 150 Om*km. Obviously, this leads to a significant increase in the capacity of the rail relative to a distant ground and can cause injury to personnel operating the traction members network. To determine the capacity of the rail at any point area must take into account the redistribution of power in the elements of the rail network, ie. E. In the rail and the transition resistance «rail - the land». The rail network is characterized by longitudinal rails Zp kilometricheskim resistance, transition resistance «rail - land» rp-s, and the characteristic impedance ZB kilometricheskim spreading factor γ rail network. Analysis of the results lead to the following conclusions: 1) contact resistance «rail-to-earth» has a significant impact on the value of the potentials arising on the elements of reverse current flow circuit; 2) the growth of the resistance «rail-to-earth», associated with seasonal fluctuations in soil resistivity, as well as in recent times, with the capital reconstruction of the roadbed, resulting in a significantly longer (up to several tens of kilometers) area, for which the potential can reach hazardous the value of human life; 3) in the circuit mode on a rail (m. E. When a metal short circuit) almost always rail network will occur potentials exceeding admissible values for several kilometers in both directions from the point of fault, which leads to removal of the dangerous potential at all metal construction connected with the rail and therefore requires a review of the principles of grounding structures.

The article discusses the traction parameters of a new generation electric locomotive. The existing schemes of service areas by electric locomotives and locomotive brigades on the studied railway test site are presented. A comparison is made of the main parameters of DC and single-phase AC electric locomotives, the operation of which is currently organized on sections of movement with trains of calculated mass in the long-term mode of thrust on the climbs of various steepness. The scheme of the proposed organization of operation of a double power locomotive and locomotive crews is presented. Calculated traction parameters of a two-system electric locomotive, taking into account the plan and profile of the track in the proposed areas of operation, specific resistivity to the movement of the locomotive and the composition of the train at the estimated speed, specific accelerating and decelerating forces of the train. When two-system electric locomotives are put into operation, it will be possible to reduce the fleet of locomotives in operation, the number of traction arms due to their lengthening and the number of locomotive change points, reduce the transit time of freight trains, increase technical and local speed, average daily mileage and average daily performance of the locomotive, reduce power consumption per traction . The operation of such electric locomotives contributes to the development of polygon technologies for managing the transportation process, improving the quantitative and qualitative indicators of various railway enterprises.

In article methods of valuation electrical parameters and mathematical models of electic processes of reinforced concrete construction are considered. The conclusion that influence of reinforced mesh was not taken into account in describe models had been done. Method for prediction of reinforced concrete foundation which based on equation system of electric field in conductors and finite element method and allowed explicit geometry of object include reinforced mesh was suggested by authors. Authors done the assumption about invariability of potential of reinforced mesh which covered of concrete layer for direct current and alternating current due to ratio of steel and concrete resistance. Realization of nethod was done by dint of software complex Comsol Multiphysics. Research object was reinforced steel foundation TSS-4, which is located in ground. Result of research was represented color epure of potential distribution and line of current density. Reinforced concrete construction current and current which flow into armature were determined by dint of integration of normal current density on surface where set the external potential and surface of armature. On the grounds of determine values of model current resistance of model depending on resistivity of concrete and ground were calculated.

Currently, according to regulatory documents, the resistivity of power line wires is assumed to be the same for any permissible load current and the heating temperature of the wires is equal to 20 degrees. This account of resistivity causes significant errors that significantly affect the operating modes of power transmission lines. This article analyzes the influence of outdoor air temperature, load current, solar radiation intensity, wind speed and direction on the heating temperature of overhead power lines, and as a result, on the value of the resistivity of the wires and power and electricity losses in them. The example of the BAM highway shows that even in the conditions of one region, the outdoor air temperature varies, depending on the time of year, within a very wide range. This in turn requires careful consideration of the dependence of the resistivity value of the line wires on the external air temperature. At the same time, it is shown that it is permissible to ignore the intensity of solar radiation, wind speed and direction on the heating temperature of overhead power lines due to the lack of comprehensive information about these factors and their opposite direction. However, this assumption will only be valid for operating currents in the range from zero to double the current value corresponding to the economic density. When calculating power losses, especially in heavily loaded lines, it is necessary to take into account all external temperature influences. Due to the appearance of sensor temperature sensors, it is proposed to use them directly to measure the heating temperature of line wires and then calculate their resistivity.

Resistive heating of the pantograph head due to the flow of traction current through the conductive elements of the upper node, has an uneven distribution along the frame structure and depends on the location of the contact wire on the insert. The aim of the work is to develop a mathematical model for calculating power losses in the pantograph panhead, allowing to estimate its value, taking into account the zigzag of the contact wire during the movement of electric rolling stock. The subject of the study is the pantograph panhead. The paper gives an example of calculating the frame skid of a pantograph equipped with carbon strips. Experimental studies of the current distribution over the shunts of the panhead depending on the position of the contact wire were carried out in February 2021 in the laboratory "Designs of contact networks, power lines and current collection devices" using a complex for testing current collection devices. The calculation of the heating power of the panhead is determined by the Joule-Lenz law. The results of the calculation showed that the maximum heating power is observed when the contact wire is in the middle of the panhead, while the places of the greatest losses located along its edges are above the places where the shunts are attached. The model makes it possible to obtain a functional dependence of the heating value along the panhead. The obtained results of the skid heating power distribution make it possible to supplement the complex model of the thermal state of the pantograph developed at the Omsk State Transport University with the participation of the authors of the article. The versatility of the developed model makes it possible to investigate various zigzags of the contact wire and evaluate the effect on the distribution of traction current along the panhead, depending on the location of the shunts and their number.