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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 sets the task of determining the level of dynamic loading in the «trolley-leash-traction motor» subsystem to reduce the dynamic impact in the «locomotive-path» system. The model of vertical vibrations of traction rolling stock, obtained on the basis of the Lagrange equation of the second kind, in the form of a system of fourteen differential equations allows us to estimate the loading of locomotive units in operation, integrated using the MathCAD application package. The approximation of random disturbances using the spectral density of the path irregularity of Professor A. I. Belyaev is chosen as the spectral density of random disturbances. A more detailed design scheme of the crew has been compiled and in order to simplify the calculation within the engineering error, a single-mass discrete model of the path is used. Entering symmetric coordinates allows us to obtain from the original system of differential equations a simplified system with characteristic equations with simple roots, therefore, the natural oscillation frequencies of the bouncing of the body, trolley and wheelset will be determined with minimal error. The transfer function is determined by Kramer's formulas. With the help of a computer, the values are calculated and graphs of the amplitude-frequency characteristics of vertical movements, maximum accelerations of the body, trolley, traction motor and wheelset of the electric locomotive in question are constructed. A comparative analysis of the calculation results and empirical data is carried out. Based on a comparative analysis, it can be argued that the considered mathematical model of vibrations of the electric locomotive 2ES6 «Sinara» is adequate and allows determining the dynamic loading of the locomotive for the entire range of operating speeds. The task of changing the existing design of the suspension system of the traction electric motor of the electric locomotive in question and the mathematical analysis of the vibrations of its nodes in further research is set.

The possibility of fatigue crack propagation in the region of compression stresses is considered. After each semi-cycle of cyclic loading the stress-strain distribution near the tip of the crack is determined by the finite element method. It is shown that maximum of the tension stresses increases in the region of compression. The obtained results allow to present the possible ways of the above-mentioned fatigue crack propagation.

The article presents an analysis of the failures of the mechanical components of the mainline electric locomotives 2ES6 «Sinara» in operation at the landfill of the West Siberian Railway, the causes and consequences of failures of the most vulnerable nodes are determined. The analysis of failures of the mechanical components showed that a significant share of them falls on the components of the wheel-motor unit of the locomotive. The analysis of the design features of the crew part is carried out. The main structural difference of suspension is the absence of leaf springs in the axle box stage, which were widely used on electric locomotives of previous generations. In the body stage, helical springs (Flexicoil) are used instead of the cradle suspension. The connection of the traction motor with the trolley frame is a pendulum. The suspension of the traction motor to the trolley frame is carried out through a leash. When considering the vibrations of railway carriages, it is customary to represent the locomotive and the track as a single mechanical system. The task of forming a mathematical model of the «electric locomotive - path» system is set and a mathematical model of vertical vibrations of an electric locomotive is formed taking into account the dynamics of wheel-motor blocks based on the Lagrange equation of the second kind in the form of a matrix equation, which allows us to assess the loading of mechanical components in operation. The mathematical model represents a system of differential equations in which six equations determine the fluctuations of the bouncing and galloping of the body and trolleys, four - the galloping of wheel-motor blocks, four - the bouncing of wheel pairs together with the reduced mass of the track. The obtained mathematical model makes it possible to determine the level of dynamic loading of the components of the mechanical part of the electric locomotive 2ES6 «Sinara» by integrating the matrix equation using the MathCAD application package.

In article the problem of determination of length of turn of structures, the total loading capacity of the transport which isn't provided with freight, quantity of freight of the transport knot which is in a timepoint in a warehouse on the basis of definition of distribution of a random variable of the freight expecting loading or unloading, and also the free capacity of vehicles taking into account restrictions on the capacity of warehouses is considered. During the solution of a task the following assumptions are accepted: capacity of cargo handling devices of transport knot isn't limited; time of the translation of giving of cars for the pogruzoch-but-unloading front and back isn't considered. The structure is understood as conditional structure which loading capacity is equal to the total loading capacity of some party of real structures, and the moment of its arrival - to the arrival moment on transport knot of the last of them. The received results can be used for determination of optimum values of warehouse capacities and a technological stock of freight of transport knot at the set goods turnover.

Analysis of failures of axlebox units of bogies for freight cars in the network of JSC «Russian Railways» for the period from 2010 to 2012, disadvantages of this node known construction trucks of the car of model 18-100. Defined vertical, horizontal and longitudinal loads acting on the buchs site. Mathematical modeling of the dynamic loading roller bearing axle-box under radial load. The influence of dynamic loads and defects in a roller bearing axle-box site on a safety of movement of the carriage.

Data on corrosion fatigue damages of a sole of rails (defect 69) on the railroads of Russia are submitted. It is established that 69 the corrosion fatigue resulting from moistening of a sole in a zone of contact with subrail laying in combination with the high level of the stretching tension in a rail sole is the reason of breaks of rails on defect. The analysis of statistical data on refusals of rails on defect 69 in the West Siberian management of infrastructure showed that failure rate grows to an operating time of the tonnage of 800 million t gross and has fatigue character. On sites of a way with a complicated plan and a profile failure rate is 3 - 4 times higher, than on quiet Trans-Siberian to the course. Results of the analysis of data are shown and measures for increase of reliability of the rail lashes having tendency to formation of defects on a code 69 are offered.

Analysis of failures bogie side frames of freight cars in the network of JSC «Russian Railways» for the period from 2006 to 2013. Disadvantages of the well-known constructions of trucks of the car of model 18-100. Mathematical modeling of movement of a wheel pair bogie 18-100, set the negative impact of the spread of the values of structural parameters of the chassis of the car on the indicators of its dynamic qualities and driving safety.