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For a radical solution of the issue of extending the service life of wheelsets of the freight cars, it is proposed to weld not only serviceable wheels, but also wheels to be pressed against an unacceptable rim thickness. It is shown that in multilayer surfacing, the possibility of obtaining high quality metal becomes more difficult, and heating of a thin rim can have an adverse effect on the gap between the inner surfaces of the wheels. The purpose of the work is to optimize the technological parameters of the multi-electrode surfacing mode, determine the amount of warpage of the wheel disk and study the quality of the deposited metal during operational tests of wheel sets. Experimental surfacing was carried out on the optimal parameters of the multi-electrode process, and a method for measuring the value of wheel warping in conditions of multilayer surfacing was proposed. The results of studies on the influence of the multi-electrode surfacing process on the metal structure and wheel warping are presented. It is shown that under the optimal surfacing mode, favorable conditions are created for obtaining fine-grained structures in the near-seamed zone. Field tests of the freight cars wheel sets were carried out to determine the efficiency and reliability of the method of automatic multi-electrode surfacing of the wheel rim. The task of the tests was a comparative assessment of the resistance of the wheels under study to defects and wear. The implementation of the task involved obtaining data for the wheel sets being researched on the number of cases of wheel failure due to the insufficient quality of the welded surfacing metal. It was found that wheel warping does not cause any dangers that threaten traffic safety, and the weld metal has the necessary resistance to cracking under the action of operational loads.

This article presents the rationale for the need to change the methodology for determining the absolute and relative values of energy losses to train traction. It is shown that when determining the relative value of the losses, it is necessary to take into account the amount of recovery energy returned to the contact network by electric rolling stock meters. To increase the accuracy of determining the absolute value of losses, it is necessary to take into account the energy consumption for the needs of the traction power supply system for prophylactic heating and smelting of ice on the wires of the contact network, as well as to ensure uninterrupted voltage on inactive electrified sections of railways. A formula is proposed for estimating the component of electric power losses in the contact network from the flow of energy recovery taking into account changes in the methodology for determining the loses of electric power for train traction.

The article discusses the process of developing an adaptive model of energy management of the railway enterprise on the basis of production rules. An algorithm for flow control of fuel and energy resources (FER) of the enterprise of the railway industry using mathematical apparatus of fuzzy logic.Proposed to use the base rules of fuzzy conclusions to assess the adequacy of the developed model of management.

In this article, the currently existing methods for determining such a technical parameter as the sliding friction coefficient were considered. The coefficient of friction is one of the main parameters characterizing the operation of tribological pairs of any engineering system. Stable and efficient operation of tribological pairs in such systems, along with high strength and fatigue characteristics, are not only the basis of safety, but also a promising direction in terms of economic benefits in the design and operation of various devices and systems. Accordingly, this area of research is very relevant for the railway industry, and for railway rolling stock in particular. This is caused by a large number of friction pairs in different nodes of passenger and freight cars, locomotives, ensuring safe and uninterrupted movement of rolling stock as a whole on iron drogs. Tribological processes are important both directly during movement and during braking processes. In this matter, the factor of determining and analyzing the sliding friction coefficient comes to the fore. One of these friction pairs is the «pad-wheel» system, which is the executive body of the braking system of a railway train. Optimization of contact in this system is one of the determining factors for the growth of braking efficiency during braking, increasing the working life of the elements of the friction pair, reducing the likelihood of defects. The search for new approaches to the study of friction issues is a direct catalyst for scientific and technological progress in the engineering industry.

The article provides a brief theoretical analysis of railway vehicle with nonlinear elastic elements. Considered distinctive features of spring suspension electric locomotives of the old and the new generations. On the basis of differences of a calculation scheme and derived a mathematical model of vertical dynamics of conditional «uniaxial» electric locomotive of new generation allows to estimate the critical speed train crew and indicators of its dynamic qualities.

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.

The structure of a complex of locomotive safety devices (CLSD) is analyzed. A comparison of technical characteristics and design features of ground stationary and transport antennas of the receiving equipment of the global satellite radio navigation system (SRNS) is made. On this basis, the importance of using SRNS in the CLSD structure is shown. It has also been shown that the decrease in locomotive positioning errors associated with the need to increase the signal-to-noise ratio at the input of the receiver can be achieved by the use of active phased array antennas (APARs). APAR are able to form narrowly directional patterns with the commutation of their maximum directions in accordance with the coordinates of the constellation's navigation satellites. Features of the formation of narrowly directional patterns and the possibility of controlling them in a linear and flat uniform APAR are considered. It is shown that the use of APAR in the ground-based equipment of the user is associated with the need: a) changing the approach to designing it for specific applications, - a flat surface of the required size should be provided in the design; b) the modernization of the algorithm for receiving and processing SRNS signals, which must take into account the finite switching time of the radiation patterns, the angle of the mask, the number and coordinate distribution of the navigation satellites in the working constellation.

Now there is no efficient decision to estimate a corrosion condition of an underground part of reinforced concrete support of contact network which is not demanding digging of a support. This problem makes actual a task of development of a hardware and software system of definition of a corrosion condition of an underground part of reinforced concrete support of contact network. As a result of work the software module allowing to realize panoramic shooting of an internal surface of an underground part of a support, to increase quality of the received images, to carry out searching of inhomogeneities and to determine their geometrical parameters, and also to make the analysis of the found inhomogeneities. Implementation of results of work will allow to reduce time and labor costs, and also to increase efficiency of diagnostic works on support of contact network.

Is executed the analysis of the special features of the process of the optimization of the complex systems of video surveillance and video registration in the territorially distributed objects of rail transport. Is proposed the procedure of setting optimization problem during the local level for the group of adjacent clusters into supers-clusters and the step-by-step optimization of entire system at the global level. The procedure of two-level optimization and the association of the adjacent information clusters of system into the supers-cluster make it possible to combine the methods of linear and dynamic programming for the optimization of the complex branched systems on the criterion of minimum expenditures.

The article considers one of the ways of improving the energy efficiency of AC electrical system railways 25 kV, 50 Hz. The proposed approach allows to determine the optimal location and capacity of an unregulated device for compensation reactive power according to the criterion of minimum active power losses in a traction electrical system. Modeling of trains on the site was made using instant schemes. Description of the traction power supply system implemented by the node potential method and Steinmetz’s symbolic method. Optimal value of reactive power for all possible locations of a compensating device was calculated numerically by an optimization method of Hooke-Jeeves according to the criterion of minimum active power losses in the traction network. The mathematical model allows to consider the elements of the traction network, schedules of trains, change of traction loads of electric locomotives, schemes of overhead network. The proposed approach was considered on the example test problem, which solution allowed to determinate the optimal location and required value of reactive power of an technical device. The placement of a compensating device in a certain place will allows to minimize the power loss in the contact network, track circuit and traction transformers from the flow of the reactive component of the current in average for all instant schemes with various traction loads. An unregulated technical device for compensating reactive power which is located between two traction substations reduces energy consumption for traction of trains on the 1 - 2 %.

The analysis of the development of the wheels increased hardness on the example of certain manufacturers, and changing regulatory and technical documentation for production (GOST). A mathematical analysis of the comparison operation wheelsets normal hardness of the wheel pairs of high hardness, based on the receipt of freight wagons from production to unscheduled maintenance. For comparison methods were used: Cramer - Welch and Laplace function. The estimation of av-erage mileage of cars on different types of wheel sets of freight cars and production technology. Developed the basic advantages of high hardness wheelsets.

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.

The article considers one of the ways of improving the energy efficiency of three-phase power supply system of industrial and railway enterprises. Presented and proved a theorem, which allows to determine the necessary conductivity and the reactive branch currents compensating device with asymmetric structure, for which the equivalent conductivity of these elements and the load will be symmetrical and active. In three-phase electric circuit of an alternating sinusoidal current reactive elements allow to redistribute active and reactive power between the phases. The use of a compensating device with asymmetric structure will reduce losses from the occurrence of reactive currents, reverse currents and zero sequence in low-voltage three-phase power system. As an example of the use of the theorem and the calculated expressions for determination of conductance of the branches of the asymmetric compensating devices a special test problem was considered. It shows the values of power losses, the coefficients of voltage unbalance with and without using the device. Considered possible options for the practical implementation of such technical devices.

The article analyzes the current state of electricity measuring on the electric rolling stock. The main shortcomings of the existing electric power measuring systems for train traction are shown. The technical requirements for information-measuring systems of electricity accounting on electric rolling stock are presented. The technology of electricity accounting on the rolling stock with the use of information-measuring complexes and the procedure for processing the measurement results are described. The minimum required list of fixing parameters during the trip is determined. The procedure for calculating the electric power consumption of electric rolling stock within the boundaries of an arbitrary electricity metering zone is given. The prospects of application of the proposed developments on the railway network are considered to provide monitoring of the transportation process energy efficiency.

In article the design of an automatic pneumatic brake of the car with the braking accelerator is offered. Use of the developed accelerator of braking of an automatic pneumatic brake by freight cars allows to reduce a brake way of the train and to reduce longitudinally dynamic forces in the train when braking.

Research the fatigue crack initiation and the fatigue crack growth in rail with thermomechanical damage. On basis of cyclic test and numerical simulation of rail deflected mode was determine a fatigue failure characteristics and fatigue crack growth characteristic in rail steel.

The article deals with measures to improve the energy efficiency of the transportation process. The necessity of creation of an automated system for monitoring the energy efficiency of the electric rolling stock. The algorithm, which allows to determine the reasons for non-locomotive crew specific rules of electricity on the trip. Developed form of protocols, reflecting the information on losses of electricity on the basis of a trip with the time and place of their origin.

The problem of emergency outages of power consumers due to the interruption of the wires of power lines due to ice formation remains relevant for today. As a solution to this problem, an electromechanical class device developed by the authors is proposed in the article. The principles of his work, the features of the design and placement on the wires are outlined. The functionality of the device in automatic mode is described. The substantiation of the maximum efficiency of electromechanical methods of struggle against icing is given in comparison with others, including thermal methods. It is necessary to search for optimal pulse parameters and the design of the actuator.

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.

In the context of the objectives of and compliance with transportation of corridors for rolling stock and improving the technology of transportation of different modes of transport considered minimization of the geometric factor in positioning navigation, peculiarities of determination of errors of coordinate of the moving objects along physically fixed trajectories on the plane, it is proved the statement about the possibility of recovery of the trajectory of the mobile point on the plane with continuous or discrete measurements of one coordinate.

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.

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.

In this article, the technical condition monitoring of power supply line for devices of railway automatics is considered. The algorithm of determining location of the break with using the mathematical apparatus of discrete Fourier transform is proposed.

The hypothesis of formation of vibration conditions of a working environment based on representation that process of formation of interaction of elements in systems with not holding connections is considered as the process consisting of several phases is offered. Those are: contact phases at which reaction of connection is positive; a phase of a transition state when reaction is equal to zero; a gap phase in which the contacting surfaces can make the independent movements. Research problems are focused on specification of theoretical ideas of dynamic interactions of a solid body with the vibrating surface on the basis of the developed mathematical models received at introduction of additional external forces and elastic connections. Dynamic interactions of elements are considered; analytical approaches in an assessment of opportunities of vibration technological processes with continuous tossing of a working environment are defined and developed. The generalized approach for problems of dynamic synthesis which basis is introduction of concept about the function of a gap allowing to prove creation of trajectories of movements of material particles according to the certain criteria reflecting properties of trajectories of the movement of material particles in interaction with the vibrating surface is offered. The method of creation of mathematical models of formation of vibration interactions taking into account the factors having technological value or criteria to which conditions of realization of the multiple modes, influence of additional forces and elastic connections belong is developed. Within the generalized approach to the solution of problems of dynamic interaction of the loose environment with the vibrating surface possibilities of use of function of a gap for an assessment and research of forms of the movement of material particles according to influence of a number of the factors reflecting parameters of a vibration field, condition of interactions with environment and features of formation of the periodic modes of tossing are considered. The theorem of conditions and opportunities of realization of the steady modes of interaction with the vibrating surface is proved. The analytical ratios defining conditions of realization of forms of processes of interaction of a loose working environment with details in technologies of vibration hardening are received. Results of approbation of recommendations about creation of technological processes in the annex to an industrial technological complex are proposed.

The article deals with the issues of joint use of a low-temperature solar collector and a heat pump in a solar heating system, the combination of which allows for high energy efficiency and stable operation of the system for the entire period of the year. The study and development of innovative technologies in alternative energy is a topical issue of today. Based on the actual statistical climatic data of the city of Omsk, a thermal calculation of the solar collector and the air heat pump in the heat supply system of the building was made. The values of solar insolation and the angle of inclination for the city of Omsk by months determined depending on latitude are given, the dependence of the change in solar insolation of the city of Omsk on the period of the year is plotted. The proposed scheme allows creating high energy efficiency and stable operation of the system during the summer and transitional months of the year. A method for calculating the generation of thermal energy using a combined system is given. The required number of tubes of solar vacuum tubular collector SVK-20A has been calculated. The work of an air heat pump and a solar collector according to a bivalent scheme is proposed, and a graph of the heat load of the heating system is also considered. The thermophysical properties of the working substance of a solar collector and an air heat pump are studied with a change in ambient temperature, the dependence of the freezing point of aqueous solutions of ethylene glycol and propylene glycol on the mass concentration of glycol is studied. A technical calculation of the COP coefficient for one of the educational buildings of OSTU was made. An effective option for using this system is proposed - heating systems «warm floor», «warm walls» or «warm ceiling».