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The article deals with the cooling and heating of individual components and assemblies diesel engines at low ambient temperatures. The more attention is paid to the description of the characteristics of the intensity of the cooling water system of diesel locomotive engines. The article presents the results of investigation of the outdoor temperature , operating conditions of load and no-load on the cooling system of. The parameters of the cooling water and engine oil that characterize the thermal conditions of the diesel engine. We reviewed and analyzed various ways of warming systems, diesel engines using airborne and stationary devices. The work is aimed at improving the efficiency of diesel locomotive at warming by reducing the operating time of the diesel engine is idling.

The paper describes a mathematical model of gas-dynamic movement through the through defects in the body of the boiler tank cars. The mathematical model allows to take into account the processes of gas flow at low pressure drop and the impact of the level of roughness of the inner surface of the through channel formation jet escaping gas. The comparison of the results of theoretical modeling and experimental studies of the velocity of the gas flow and temperature under different conditions. The study identified the laws of gas flow through a series of classic models through defects. Shows the dependence of the temperature of the escaping gas flow from the exhaust velocity and the level of roughness of the internal surface of the through channel, which allows us to estimate the nature of gas flow and temperature gradient. The obtained results allow to adjust the level of sensitivity to rejection temperature during thermal leakage control boilers railway tanks.

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.

The results of mathematical modeling of the heating process of the wheel material during braking mode of the locomotive are presented in article. The results can be used to calculate the temperature change for any point of the wheel during the braking operation.

The article assesses the influencing factors for electric power consumption for the needs of the electric locomotives of the 2ES6 series, statistical models for normalizing the electric power consumption for own power have been generated, and their quality has been assessed.

The heating of the pantograph panhead of an electric rolling stock is caused by the removal of the traction electric current. The increase in temperature is due to the characteristics of the catenary and conductive materials of the suspension and current collector. Current collection low quality also leads to overheating of contact materials and limits the passage of the maximum permissible long-time current when the electric locomotive moves. The uneven distribution of temperature leads to local points of overheating and an inefficient use of the surface of the contact strips. The presented graphs of the density distribution of the position of the contact wire in the plan indicate their dependence on the profile of the path section and the type of the catenary, which determine the heat distribution along the panhead. The proposed methodology of the factor analysis of the effect on the current collector's panhead heating makes it possible to determine the causes of its uneven heating and propose measures to reduce the share of influence of each factors and to provide an increase in the removal of the traction current.

In article the way increases in system effectiveness of cooling locomotives in operation - use relaunches of heat carriers between contours is considered.

The technical condition of the cylinder-piston group has significant effect on the reliable operation of the diesel locomotive engines. The most susceptible to the premature failure is the head of cylinders. It is caused by the heat release rate of the combustion chamber detail. The increase of the diesel locomotive engines cylinder heads durability in operation causes the relevance of the researches. In the article the set of the factors influencing on the diesel locomotive engine cylinder heads durability is defined, their main groups and subgroups are found. In the offered classification the subjective factors which directly depend on the human activity are dominated. It is possible to reduce the influence of the subjective factors by means of the human activity wrong solutions reduction while operating and repairing locomotives. The measures that improve diesel locomotive engine operation and positively affect the reliability of the cylinder heads are considered. Simple in implementation methods to extend the service life of the cylinder-piston group are offered. They are decreasing temperatures gradient during the post-stopping period of the power point and upgrading cooling system.

Solidifying transportation of goods by rail, namely, tank wagons is accompanied a number of difficulties. These include: lowering the temperature of the transported oil, accompanied by the growth of its viscosity, the inability to quickly discharge, change in performance of transported oil products, an increase in idle tank cars. The analysis of the cooling rate of the goods transported, depending on the size and thickness of the insulating layer. Introduced formulas show that the presence of the heat-insulating sheath is cylindrical vessel radius deviation from the optimum value. When this thermal insulation reduces considerably the heat transfer coefficient in the surrounding area and to accelerate the discharge process.

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 presents a method of calculation of the thermal state of the pantograph head. The density of the suspension zigzag distribution, taking into account a number of assumptions, has replaced the contact wire position function in the plan. Results of calculating the temperature of the pantograph head at different width of the zigzag of the typical suspension, including zero, are presented. The influence of sinusoidal and tangential contact suspensions on the temperature distribution of the pantograph head is estimated.

The results of infrared studies of the process of heating parts collector and brush assembly dc electrical machines. Proved diagnostic parameters for assessing the technical condition of the collector-brush assembly of electric motors: the ratio of changes in the elevation of temperature in time and space.

The aim of the work, the results of which are presented in this article, is to identify effective parameter of the heating process in the collector-brush unit of DC traction motor. The article suggests a detailed equivalent thermal equation of DC traction collector-brush unit. An experiment in a laboratory according to the theory of experimental design in the central rotatable terms of the second order are held, and the analysis of the results are presented. A method for processing the results of thermographic study of the machine is described. The regression equation, reflecting the degree of influence of the mode parameters of the machine on the intensity of the heating area of traction motor collector-brush unit, is compiled. The correct use of mathematical apparatus is confirmed by quantitative calculations Student's criteria assessing the significance of the coefficients of equations and F-Fisher criterion within the 5 % significance level. The results can be used to supplement the methods of DC traction motors and collector-brush unit technical condition diagnostics.

The contact line is a special kind of power overhead line with multiple electrical connections of wires, which form a complex topology of the linear electrical circuit. Analytical models simplify the real topology of the contact line and it limits their functional application. It is possible to take into account the topology of contact line when using tools of computer simulation, but it entails complicating the computational algorithms of the model. The aim of this article is to determine the conditions for the application of current distribution models and the development prospects in this area. The article describes the existing models for calculating the current distribution in DC contact line: a model of natural current distribution, linear analytical models, model with an infinite number of droppers, a model with a direct application of Kirchhoff's circuit laws in matrix form, and a finite element model. The article contains the main provisions and calculation capabilities of each model. Contact line KS-250-3 acts as a calculation catenary for the comparison of current distribution models. You can use the results of the article to select the optimal design distribution model for the design of the contact line, thermal analysis, current-carrying capacity calculation, identification and elimination of «weak point».

As a result of tension increase and significantly loads on the overhead contact lines, there is need to research the tensile stress value for contact and messenger wires. In this paper, the author reviewed the wires operation conditions concerning the thermo-mechanical load. The author has analyzed the results of contact wires low-temperature creep tests. The real rate of contact wires creep is as appropriate as the standard values. At the same time, copper wire elongation is faster than bronze. The author has provided results about contact and messenger wires ultimate tensile stress tests, heated at different temperatures. The ultimate tensile stress rate for the copper and bronze contact wires is reducing by 9 % with temperatures increasing. The ultimate tensile stress rate for the cop-per messenger wires is reducing by 11 %, for the bronze wires - by 4 %, with rising temperatures to 150 °С. Test results have shown that heating of copper wires to temperatures above 90 °С and bronze wires to temperatures above 120 °С leads to a significant immediate reduction of strength. Working conditions for the overhead contact lines wires are close to the critical one. It is not sufficient for reliable and safe operation Author offers to modify regulatory requirements for contact and mes-senger wires concerning permissible heating and also not to divide short-term and long-term heat-ing and only to leave permissible heating.

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.

The article presents an improved mathematical model of the thermal state of the pantograph head for calculating the temperature distribution when interacting with different catenary with a double contact wire. The model takes into account the unevenness of the pantograph contact pressure on the wires along the suspension span and between them, allows using the databases of the car-laboratory for testing the contact network, calculating the thermal conditions of the skid on various sections of electrified Railways, including transients between them. The paper presents graphs of the zigzag distribution density of the contact wire of the Moscow - Saint Petersburg high-speed line, and defines the transient and steady state thermal states of the pantograph head when the pantograph interacts with them.

In the article the peculiarities and the advantages of using dynamic modes for diagnosing units of rolling stock. Specific examples of the diagnostics of separate units of the locomotive vibration, temperature, electrical parameters, frequency of rotation. The urgency of the task of developing diagnostic systems using the reference models.

In this article, with the help of software, the relationship between the structure of the material of the brake pad and the temperature distribution of thermal stress on it is established. Spatio-temporal distributions of thermal stresses were analytically determined for the surface layer of the friction element based on the model of a three-section brake pad with non-fixed edges. At present, shoe brake is widely used for freight trains. It converts dynamic energy into thermal energy using the friction between the pads and the wheel, and then dissipates the thermal energy through a heat exchanger. This process includes heat transfer, design features, mechanical characteristics, material properties and other. The article pays special attention to the brake pad pressure, braking mode, brake pad material and other factors. Modeling of thermal effects is the most important in the design of vehicle parts and assemblies. Thermal research is an important step in the study of braking systems namely railway vehicles, where it is necessary to breakе large masses, since the thermal load on the braked railway wheel prevails compared to other types of loads. In this paper, the thermal stress on the friction element of the shoe during braking is investigated. In frictional braking, the process of friction between the brake pad and the wheel occurs at the points of actual contact. The heat flow from the points of actual contact spreads over the entire geometric area of the block.

The questions of the composition of the design and technology of smelting, casting and heat treatment of alloyed rail steels having high operational stability. Together specialists EVRAZ ZSMK Novokuznetsk and IrGUPS was proposed complex doping scheme of the rail steel and rail rolling floor EVRAZ ZSMK was conducted testing of the technology of smelting and eletropechnoy thermostrengthening superperlitnoy steel of high purity, which has high wear resistance. several experimental batches were produced rails, which are tested on the site of the saddle-point Irkutsk-Slyudyanka VSZHD with an unfavorable combination of operational loads, causing increased wear of the rails. The test results showed high wear resistance experienced rails and expediency of development of industrial production.

A mathematical model of thermal processes (dynamic) contact current collector with contact suspension (in motion), which allows to estimate the temperature distribution of heating the current collector during movement. The experimental evaluation of the proposed cooling device performance is given. The thermal model of the current collector in motion mode has been verified.

Example of the methods to evaluate conditions and reserve of transverse stability in CWR curves under abnormal track maintenance is discussed in the article. The author presents the results of the research of this method and also its positive effect is described.

The article deals with the issue of the formation of defects of thermomechanical origin (sliders) on the rolling surface of wagon wheels during their skidding along the rail, since such defects affect traffic safety to a greater extent. In addition, such defects on the tread surface of the wheel are difficult to eliminate in the repair industry. It is known that the slider is formed when the wheel is jammed and its translational movement (sliding) along the rail, the so-called skid. As a result, in the area of contact between the wheel and the rail, intensive wear of the wheel material is observed, as a softer element, and a wear area (slider) is formed. The slider is evaluated by such a parameter as the depth relative to the wheel tread. An algorithm for calculating the depth of the slider is given under the condition of a short-term movement of the wheel along the rail skidding. The initial data were determined and a calculation was made with the construction of graphs that reflect the dependence of the slider depth on the speed of the rolling stock and the load on the axle of the wheelset during short-term skidding. A technique for calculating the maximum temperatures in a pair of sliding friction "wheel-rail" is described. The values of the maximum temperatures in the contact patch are calculated when the wheel moves along the rail skidding. Based on the results of the calculations, graphs of changes in the maximum temperatures on the wheel tread surface in the area of friction on the rail under various operating conditions were plotted. An assessment is made of the possibility of indirect determination of the depth of the hardened metal layer in the area of the slider, depending on its dimensions, measured when the wheelset was received for repair.

The article outlines modern approaches to determining the maximum permissible continuous current of current collectors when stopping and in motion. The features of techniques that reliably take into account operational factors when conducting tests in laboratory conditions are considered. A mathematical model is given for studying the distribution of current load in emergency mode of breaking a current-carrying shunt.

This article presents an algorithm and a method for calculating power flow of an open electric network with a voltage of 6-35 kV, taking into account the temperature dependence of active resistances. Calculation of the electric and thermal conditions of the electric network is carried out with a joint solution of the equations. The determination of stresses in the nodes is carried out using the inverse matrix of the nodal and intrinsic conductivities. The inverse matrix of nodal and intrinsic conductivities is determined based on the well-known direct Jordan-Gauss method. The equation of the heat balance of the wire used to calculate the actual temperature is solved numerically. Convective heat transfer is recorded only for forced convection, because wires of overhead power lines with a voltage of 6 kV and higher are located on various types of poles, at a height of at least 10 m. This fact allows us to abandon the use of formulas for natural convection and use expressions only for forced convection. Accounting for solar radiation in the presented algorithm is possible on the basis of two methods: simplified and considered in the standard of PJSC FGC UES, which allows you to take into account the actual location of the wire relative to the north. Using the test circuit as an example, the steady-state mode was calculated taking into account the temperature dependence of the active resistances. The results of a numerical experiment are presented, confirming the operability of the developed algorithm. The refinement in determining active power losses with and without taking into account the heating factor for the considered circuit is about 13%. Verification of the algorithm that implements the method of calculating the steady state (SS) of an open electrical network of a medium voltage class taking into account the temperature dependence of active resistances showed that in technically acceptable modes the developed algorithm has good accuracy in comparison with the RastrWin3 software package.