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The article presents the results of studies of the effect of material properties and wheel failures on the process of their machining on the on the car wheel lathe. Developed by complex criterion that takes into account the effect of various factors on the allowable cutting speed. The proposed method for assessing the machinability of cutting wheels through additive criteria. The quantitative characteristics of the machinability of cutting are obtained, taking into account the macroscopic imprecision of the geometric shape, defects in the thermomechanical interaction of the wheel, brake pad and rail, surface defects of the rim, work hardening and the presence of zones of increased hardness. The results can be used in the development of methods to reduce the consumption of carbide cutting tools for machining parts of rolling stock with operational defects.

Annually locomotive-building plants, equipment suppliers and service companies develop organizational and technical measures aimed at improving the reliability of products. Thus, within the framework of the contract for the supply and maintenance of electric locomotives of the ERMAK series, a number of corrective measures have been implemented in more than thirty directions, many of which have achieved a positive result. However, during the long-term operation, more and more new hidden technical defects are revealed, and in rare cases, the measures taken are not enough. The manifestation of systemic inconsistencies is random in nature, thereby they negatively affect the dynamics of the average daily mileage and the linear mileage completed over the entire life cycle, causing unpredictable fluctuations, and as a result, the organization of service planning and budgeting to support the life cycle of locomotives. Therefore, there is a need to develop a model for a more accurate forecast of the average daily mileage for a long period, considering the impact of system inconsistencies and corrective measures to improve the reliability of nodes. The article uses the Pareto principle to analyze system malfunctions of locomotives manufactured by PC NEVZ LLC for the period of operation from 2018 to 2021, analyzes the dynamics of the average daily mileage of the locomotive fleet of the Far Eastern Traction Directorate with the use of a statistical and analytical method, analyzes the impact of failures on the average daily mileage using the Fourier time series forecasting method. On the example of malfunctions of power current-carrying buses of a rectifier-inverter converter and malfunctions of latches of a high-voltage vacuum circuit breaker, the influence of malfunctions of critical nodes is evaluated.

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 considers technical solutions to improve the quality of life support system in long-distance passenger trains (PVPDS), in particular in the water supply and ventilation systems, which ensure safe and comfortable passenger travel conditions. The quality of water in the coach is determined by the conditions of initial water filling at the intermediate stations, which can be adversely affected by the sanitary condition of the storage tank. Currently filters are installed in the ventilation system, efficiency of which is questionable in pandemic conditions. Scientific works and elaborations of native and foreign scientists, up-to-date concepts of organizing comfortable conditions in the PVPDS, as well as methodical and normative-reference materials on the given theme were used when writing the article. The effectiveness of the proposed method was confirmed in the course of experimental research, the results of which were used in the implementation of the investment project "Clean Water" of JSC "Russian Railways". Technical solutions have been proposed to improve the quality of life support systems using ozonization technology. Their realization will allow the life support system to operate in the water purification and disinfection mode and sterilization the air environment in the PVPDS. The condition for the efficient use is the availability of compressed air for the ejector operation in the mode of supplying the ozone-air mixture required for water and air cleaning and disinfection in the car. Ozonization is performed separately in the automatic mode. The ozone method for solving the problems of life support in coach cars is a perspective direction consider its generality and, therefore, ability of using it on the infrastructure objects for disinfection and sterilization of premises, reserved volumes and production capacities.

In article the question about possibility of extension of service life of carriage wheels by influence on technological parameters of restoration of their driving profile is considered. The correlation analysis of statistical data on volumes of machining and the size of defects on a driving surface of the wheels coming to repair is made. The mechanism of purpose of an allowance for machining of a driving profile of a wheel which will allow to reduce an unreasonable consumption of metal of a rim of a wheel in shaving is offered.

The deterministic evaluation of the durability of railway rolling stock structures according to fatigue safety factors, established by regulatory requirements, does not fully take into account the random nature of loads that cause the accumulation of fatigue damages, the operation rate (operating time), does not allow to evaluate the operating life and its depletion over the service lifetime. At the same time, with the development of heavy and high-speed traffic, as well as due to the introduction of technical regulations, the task to evaluate and substantiate the assigned service lifetime and operating life of railway vehicles are becoming more important. The subject of the study, the results of which are presented in this article, was the fatigue strength of elements of locomotive basic parts. The purpose of the work was the prediction of their limit state by the operating life of critical elements. In the present work, design and experimental studies have been performed with running dynamic and strength tests of the locomotive in the entire range of operating speeds of its running, determining the stress-strain state of structures using strain-gauge methods, calculating safety factors with the probabilistic estimate of the fatigue strength of parts. According to results obtained, the influence of the operation loading performance on the fatigue strength margin and its depletion during the element operating life is shown. According to the results of this work, it can be concluded that main indicators of the strength, operating life and service lifetime of the locomotive make it possible to compare and link their key parameters for the subsequent analysis, substantiation, rating and control of safe operating life of railway equipment.

The article is devoted to the definition of rational overhaul runs equipment of locomotives. This has an impact not only on the reliability of the rolling stock, but also on safety. As a method chosen for the implementation of this task, the functions of the failure rate are used, with the subsequent construction of the functions of resource distribution and determining 90 % of the resource of the equipment of electric locomotives. The proposed technique allows you to determine the rational timing of maintenance and repair of locomotives in the specific conditions of their operation. The calculations are based on information about changes in the technical condition of the wheel-motor block of VL10 electric locomotives.

In the article it is developed a model for the locomotives life cycle managing in their maintenance and repair using automated technical diagnostic systems. Based on statistical analysis of data on the operation of locomotives, the impact of the reliability of the locomotive and its maintenance and repair system on the efficiency of locomotives is theoretically justified. A method of analyzing the technical diagnostic systems effectiveness using the mathematical apparatus of information theory and of predicting the duration of maintenance and repair time with the dynamic use of accumulated statistics on the duration of previous repairs has been developed.

In article from positions of uniform life cycle locomotives, from creation before write-off, the major factors influencing the level of their reliability are considered. Value of these factors will give the chance to connect mathematical model the potential level of reliability put in the specification on design of new locomotives with the actual reliability in specific conditions of operation and on this basis to determine the optimum parameters systems of maintenance and repair corresponding to maximum efficiency of use locomotives for all life cycle.

The article presents the equivalent circuit of three conductors, taking into account their mutual influence. The equivalent circuit contains the resistance and inductance of each conductor, the conductivity and the capacitance of their insulation relative to the earth, as well as the mutual inductances, conductivities and capacitances of the insulation between the conductors. The mathematical foundations of calculating the distribution of electrical quantities in the system of three conductors are considered, taking into account their mutual influence. An iterative incremental model of the software life cycle was chosen as the basis for automating this calculation, taking into account existing approaches to software development. Specific features of specialized software are specified. A structural scheme of the software complex and a block diagram of the calculation algorithm are proposed. The algorithm is based on the iterative calculation of currents and voltages for three conductors, taking into account their mutual influence. In accordance with the chosen model of the life cycle of the software, three versions of software with different functionality have been developed. This allowed us to effectively organize the processes of testing, debugging and implementation. As a result, the software complex has a window interface containing four tabs and allowing to enter the initial data for the calculation, display the results in the form of graphs and tables. For saving the results of calculations, a connection with the database has been implemented.

The need to apply various methods for predicting the technical condition of reinforced concrete supports of the contact network is currently a necessary condition for ensuring the safety of train traffic. Such a need arose due to the presence in operation of supports with extended service life, in the absence of a reduction in loads, without the presence of various kinds of redundancy. The article describes a method for predicting the technical state of the supports of the contact network. Solving the problem of exploitation, which consists in the fact that it is rather difficult to reveal the system of failures of the considered object of exploitation, under the influence of many factors. The probability of finding the contact network supports in a certain state is expressed through the statistical properties of the contact network supports, based on the change in the carrying capacity

Evaluation of fatigue life is based on the use of basic fatigue curves. However, due to large va-riety of possible design solutions basic fatigue curves cannot be calculated for all cases. In addi-tion, the production practice has a significant influence on the durability of structural elements. To predict the fatigue durability using the traditional method we need to consider the influence of structural and technological factors by introducing the correction coefficients established on the basis of the experience and accumulated experimental data. The correction coefficients are widely used in calculating the resource elements by domestic and foreign construction firms. Using the traditional method the match of the projected longevity and durability resulted in a bench test struc-tures are not always satisfactory. Often by conducting rapid analysis the sufficient fatigue curves absent, the closest in characteristics among the available are selected. The article presents the im-proved technique of numerical fatigue life prediction of structural elements by using the modified fatigue curves, considering the impact of structural and technological features of the products of the actual design. The results of calculated estimate of the resistance of fatigue thin-walled struc-tures and their comparison with experimental data are presented. On the basis of the work carried out was drawn the conclusion that by using the method of calculation of fatigue longevity using modified fatigue curves , considering the structural features fragments of products, the convergence of the results of predicting fatigue life and test bench results obtained higher than by using tradi-tional techniques.

In research consider a methodology the remaining life assessment of rail with fatigue crack in lower flange. Obtain the stress intensity factor equations for crack size and kind of stress: bending stress, thermal and residual stress. Make up an fatigue strength analysis of rail P65 and under different conditions of loading and remaining life calculation of damaged rail when given conditions of loading. Submit a assessment evaluation rail reinforcement in cyclic crack growth rate.

Using the example of operating gas fields in the Western Siberia, the issue of the correct choice of voltage class, considering all the periods of gas fields life cycle, appears. Wrong choice of the voltage class leads to braking development of a gas field. Gas field technological scheme during the each period of the life cycle is considered, the dynamics of the electrical load is estimated. The analysis of existing methods of choosing the voltage class is carried out and their flaws are revealed. Mathematical models of the optimal voltage class calculation and discounted costs calculation are developed using the theory of experiment planning. An algorithm of choosing the optimal voltage is developed and the distribution and supply networks of the external power supply system of the existing gas fields in Western Siberia are investigated. Progressive voltage class for power supply and distribution network is proposed. Conclusions are made.

The results of mathematical modeling of the optimization of maintenance cable lines are presented in article. The results can be used to calculate the optimal frequency and number of major repairs and substitutions of cable lines.