The largest part of operating fleet of EMU trains, operated on the railways of the JSC “Russian Railways”, belongs to the category “ЭП” - electric commuter trains for transporting passengers in suburban areas with a length of the turnover section not exceeding 200 km with a speed of up to 120 km/h. The category of “ЭП” electric trains is fully formed by the domestic rolling stock produced since 1993. After putting Safety Norms NB ZhT 03-98 into force in 1998 and subsequently entering Technical Regulations of the Customs Union - TR TS 001/2011 virtually all new or upgraded series of EMU trains of the category «ЭП» within the acceptance and certification tests were experimentally investigated by the Test Loop of the JSC “VNIIZhT” (ITs ZhT) for compliance with safety requirements from the conditions for ensuring normative level of indicators of interaction between rolling stock and the track. Main technical parameters were shown as well as design features of carriage part of EMU trains of the category “ЭП”. The following features were considered: comparative quantitative values and dependencies on the travel speed and the level of unbalanced accelerations of the experimental indicators of influence on the track of EMU train cars of the category “ЭП”, determined from the results of statistical processing of realizations of dynamic stresses in the throttle of rail sole and lateral forces; vertical and lateral (horizontal) forces transmitted from the wheels to the rail head; stability coefficients of assembled rails and sleepers from the transverse shift along the ballast, as well as the coefficients f of the transition from the axial stresses in the base of the rail to the stresses in the outer edge of the rail sole. The quantitative values of the impact indicators on the track of EMU train cars of the category “ЭП” with a design speed of 120 km/h, obtained from the results of complex certification and acceptance tests, are in the range of values regulated by the current regulatory documents. It is recommended to use the values of the impact indicators on the track to evaluate the design of the carriage part of EMU train cars at the design stage.

At present, specialists of foreign and domestic research organizations and industrial firms pay much attention to the use of steam compression heat pump plants (HPP) as an energy-saving technology. Modern compressor units allow receiving 3-4 kW for 1 kW of power consumed by HPP, and under certain conditions up to 5-6 kW of useful power. Today HPPs are most used in heat supply systems for residential and office buildings, especially in Scandinavia, Germany, Switzerland, USA, Japan, China. The paper discusses features of the operation of steam compressor heat pump plants as systems for improving energy efficiency with a description of the device of a heat pump plant; its main components are also listed. Review of the existing practice of introducing such systems in foreign countries is presented, including in Minsk - the Minsk metro, and in Russia - the Moscow Metro. The project, performed by specialists of JSC “VNIIZhT” and MIIT, is considered for the Moscow Metro (with reference to the heating systems of the Nagatinskaya and Pushkinskaya metro stations) for the use of dumping heat of ventilation shafts for heating and hot water supply, proposed by scientists of JSC “VNIIZhT” in 2012 within the framework of the exhibition of technical achievements. Authors presented information on the implementation of the pilot project at the station “Salar’yevo” (Moscow Metro) on the use of HPP in the heat and cooling supply system of the station for further comprehensive analysis of the effectiveness of the HPP application in the operating conditions of the metro. From the analysis of the data given in the work, it is concluded that metro systems are significant sources of low-potential heat, which can be used for the heat supply of stations and/or nearby urban sites by means of HPP. By now, there is a lot of experience (especially abroad) of the practical application of HPP in the heat supply systems of facilities. Nevertheless, for a reliable and comprehensive assessment of the feasibility and cost-effectiveness of projects using low-potential heat of metro systems as an energy-saving technology, a complex of studies is needed, including operational tests of currently implemented pilot projects.

One of the key problems of organizing an effective The article considers problems of the influence of technical transportation process is an adequate reflection of the current and technological parameters of freight transportation by rail on pricing factors in the tariff system. This can be done on the basis of the cost price for tariff purposes, the distribution of the cost of the the development of appropriate models for determining the cost initial-final operation between loaded and empty cars, determinaof transportation. Modeling the cost of transporting freights by rail tion of coefficients taking into account the length of cars and the for tariff purposes is based on determining and assessing the rela-distance of transportation, as well as the methodology for the distionship between transportation costs and work indexes. tribution of costs between the initial-final and motion operations. Proposed updated methodology for constructing parametric models for determining the cost of transportation of freights for tariff setting purposes includes: method of itemized distribution of expenditures between non-commercial organizations and affiliated subsidiaries in terms of infrastructure and traction; procedure for allocating the costs, attributed to affiliated subsidiaries, to the indexes “ton-kilometer gross” and “car-kilometer”; system of itemized distribution of freight costs for the indexes of the transportation operation, as well as the system for calculating the aggregate expenditure rates (AER) used in parametric models of the cost price; actualized assessment of the influence of the length of the car on the cost value for tariff setting purposes; procedure for allocating the cost of initial-final operations between loaded and empty cars. The developed parametric models for calculating the cost of transportation for tariff purposes for transportation by the locomotive of the JSC “Russian Railways” take into account such factors as the distance of transportation, the weight of the container and the length of the car, its loading, the type of shipment. Within the framework of creating new parametric models, the following factors have been updated: coefficients that take into account the length of the car; coefficients that take into account the effect on the cost of production up to the distance of transportation in connection with the change in the relative distance of carriage of the car as part of mixed and transfer-and-export trains; coefficients depending on the type of shipment.

Current geopolitical and economic conditions for the functioning of railway transport in most post-Soviet states are such that it is extremely difficult to provide required quality of transport services and break-even operations at high expenses for maintaining the railway infrastructure and rolling stock. Dynamics of transportation of the Tajik Railway (TSR) is shown, which displays that most of its sections are classified as low-intensity ones. The paper proposes methodical principles, setting and qualitative analysis of the task of rationalization of operational work and organization of car flows for international transportation, taking into account the specifics of the Tajik Railway. There is a problem of complex maintenance of the efficiency of operational work in modern conditions based on the synthesis of the tasks of self-management (rational internal operational technology of the Tajik Railway) and coordination tasks (technological interaction with railway administrations of other states). Author substantiated the necessity of solving this problem. Proposed classification of technological restrictions and controlled variables in the performance of transport takes into account methods for changing external conditions for the functioning of the railway landfill and methods for increasing internal efficiency of its operation. The search for the solution of the problem involves direct search of variants along its ordered set with clipping of groups of variants that do not correspond to constraints, with the subsequent finding of compromise control over a set of effective alternatives.

To date, there is a large number of programs that simulate the train operation of the locomotive using the method of traction calculations. As input data in the program, information is entered about the track section, locomotive and train composition. The drawback of modeling the train motion using the traction calculation method is the obtaining of a local unimportant result for a particular section of the track. The article proposes a new approach to modeling the operation of freight mainline locomotive. The train operation of the mainline locomotive is represented by a limited number of generalized modes depending in turn on a limited set of initial conditions - the profile of the track section, the weight of the train, the speed of the locomotive, etc. In this case, the elements of the set of initial conditions are random variables. The advantage of the proposed approach is the ability to give a generalized assessment of the change in the performance of the locomotive train when introducing new elements and control algorithms into the diesel generator unit without linking to a particular section of the track. Comparison of the time of work on the positions of the driver's controller was obtained during the year by mathematical modeling and experienced runs with diesel locomotives of the 2TE116U series at Oktyabrskaya Railway, a branch of the Russian Railways. It showed that the maximum discrepancy between calculated and experimental data does not exceed 5 %. The proposed algorithm for simulating the train operation of the freight mainline locomotive allows reproducing the locomotive train performance parameters with an acceptable accuracy for practice. It can be used to obtain quantitative estimates of the impact of changes in the performance of the train operation of long-distance freight diesel locomotives when new elements and control algorithms are introduced into the diesel generator unit.

The article compares the results of calculation of the finite element simulation of current and temperature distribution in the scale model of the DC catenary with the data of laboratory tests. Researches were carried on various versions of the structural design of catenary model, reflecting the topological features of the wire connection, characteristic of the DC contact network. The proportions of the cross-sectional area of the scaled model wires are comparable to each other with the corresponding values for real DC catenary. The article deals with the operating conditions of the catenary model in the modes of transit and current collection. When studying the operation of the scale catenary model in the transit mode, the effect of the structural elements on the current distribution and heating of the wires was obtained. Within the framework of the scale model, theoretical assumptions about the current overload of the supporting cable near the middle anchoring have been confirmed. In the current collection mode, the experimental dependences of the current in the transverse wires of the scale model are obtained from the coordinate of the current collection point. Using the model it was experimentally confirmed that in the section of the contact wire with local wear, not only the temperature rise occurs but also the current redistribution due to the smaller cross section. Thus, the current share in other longitudinal wires of the scale model increases and their temperature rises. Scale and mathematical models are constructed with allowance for laboratory clamps and supporting elements that participate in the removal of heat from the investigated wires. Obtained study results of the scale model allow to draw a conclusion about the adequacy of the mathematical model and its correspondence to the real physical process. These conclusions indicate the possibility of applying mathematical model for calculating real catenary, taking into account the uneven contact wear wire and the armature of the contact network.

Railway bogie is the basic element that determines the force, kinematic, power and other parameters of the rolling stock, and its movement in the railway track has not been studied enough. Classical calculation of the kinematic and dynamic parameters of the bogie's motion with the determination of the position of its center of rotation, the instantaneous axes of rotation of wheelsets, the magnitudes and directions of all forces present a difficult problem even in quasi-static theory. The paper shows a simplified method that allows one to explain, within the limits of one article, the main kinematic and force parameters of the bogie movement (installation angles, clearance between the wheel flanges and side surfaces of the rails), wear and contact damage to the wheels and rails. Tribology of the railway bogie is an important part of transport tribology, the foundation of the theory of wheel-rail tribosystem, without which it is impossible to understand the mechanisms of catastrophic wear, derailments, contact fatigue, cohesion of wheels and rails. In the article basic questions are considered, without which it is impossible to analyze the movement of the bogie: physical foundations of wheel movement along the rail, types of relative motion of contacting bodies, tribological characteristics linking the force and kinematic parameters of the bogie. Kinematics and dynamics of a two-wheeled bogie-rail bicycle are analyzed instead of a single wheel and a wheelset, which makes it clearer and easier to explain how and what forces act on the bogie and how they affect on its position in the rail track. To calculate the motion parameters of a four-wheeled bogie, it is represented as two two-wheeled, moving each on its own rail. Connections between them are replaced by moments with respect to the point of contact between the flange of the guide wheel and the rail. This approach made it possible to give an approximate estimation of the main kinematic and force parameters of the motion of an ideal bogie (without axes skewing) in curves, to understand how the corners of the bogie installation and the gaps between the flanges of the wheels and rails vary when moving with different speeds, how wear and contact injuries arise and to give recommendations for their assessment and elimination.

Quality of passenger cars is a complex property, depending on the reliability and functional safety of the cars. Therefore, guided by the standard definition of the term "quality", satisfaction of the parties concerned, in this case passengers, customer, carrier, infrastructure owner, supplier or state supervision bodies, can be achieved by meeting the requirements objectively established to the noted indicators. In order to establish the requirements for the reliability and functional safety of passenger cars, it is necessary to solve the following tasks: Selection of the nomenclature of indicators taking into account the peculiarities of using passenger cars for their intended purpose. Development of calculation methods and selection of parameters of test plans for reliability for the established nomenclature of indicators. Determination of the achieved level of reliability and safety of cars based on selected indicators. Establishment of standardized values of indicators taking into account achieved level on the basis of the principle of reasonable sufficiency. The article shows the nomenclature of the applied indicators of reliability and safety of passenger cars, as well as formulas for their calculation, accepted criteria for failures and limiting states of cars, requirements for the accuracy and reliability of the measured indicators. The work concludes that the establishment of requirements for indicators of reliability and functional safety of passenger cars allows taking into account the interests of all involved parties. For passengers, infrastructure owner and state supervision bodies, interests in the field of traffic safety will be taken into account; for the carrier - these requirements will be taken into account in terms of timely and safe transportation of passengers; for the customer - in terms of ensuring the good technical condition of the cars; for the manufacturer - in terms of preserving the reputation, ensuring the competitiveness of products, reducing costs to eliminate inconsistencies in its quality.

The first frequency of the own bending vibrations of the car body of the EMU train is one of the main normalized parameters associated with smooth running. Estimation of this parameter at the design stage allows to accelerate the process of development of design documentation and to reduce further number of tests. Rigidity of the undercarriage and roof equipment of the EMU train cars contributes to the overall rigidity of the body. When simulating the equipment with concentrated masses at the attachment points, underestimating the rigidity of the body results in underestimated values of the first natural frequency of bending vibrations of the body. It is shown that modeling the equipment with a rigid area with subordinate nodes at the attachment points makes it possible to simplify the process of constructing the model and adequately take into account the rigidity of the equipment not only in determining the static characteristics of body deflections, but also in calculating the dynamic characteristic and the first natural frequency. Using subordinate nodes of a rigid area on the surfaces of the fixing holes leads to a reassessment of the natural frequency. Value of the first natural frequency of the body oscillations is linearly dependent on the specific weight of the undercarriage equipment. When designing the bodies of EMU train cars (especially motor cars), in order to increase the frequency value, the equipment boxes should be located, taking into account the compatibility of the deformations of the box frames and the loadbearing structure of the body. Massive boxes for small equipment should be placed as close to the bolster beams as possible. If it is necessary to place largesize boxes under the car equipment, one should consider variants of its location in the central part of the body to include the box frames in the bend of the transverse beams of the frame.