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Rail transport has been the leading sector of the whole transport network. In order to improve the efficiency of its functioning, it is important to develop measures that may help reduce the maintenance cost. To improve the open wagon hatch door strength, it is proposed to make it with rectangular corrugations. The results of calculations show that, taking into account the proposed solution, the weight of the improved hatch door is almost 10% lower than the weight of a typical one. The strength of the hatch door under static loads was calculated. The results of calculations show that the strength of the hatch door under the diagrams considered is ensured. The study will contribute to the development of best practices for modern structures of railway vehicles and increase their cost-effective operation. [ABSTRACT FROM AUTHOR]

The analysis of the statistical values of wear of brake pads in operation, based on which a wear model was developed, is presented in this paper. This model can be used for predicting the remaining service life of brake pads according to the wagon mileage. The distribution function of wear on the upper and lower parts of the pad was determined, which made it possible to find the main qualitative characteristics, namely, the wear intensity, the γ-percentage wear, and the average pad wear at a specified wagon mileage. The results of the study can be factored for solving complex engineering problems of excessive wear of composite brake pads used for freight rolling stock; they could also help to extend the guaranteed overhaul period and improve the railway traffic safety. [ABSTRACT FROM AUTHOR]

The features of designing the frame of a universal container made of square pipes are presented in this paper. The two frame loading schemes are taken into account: the effect of vertical loading on the container frame when it is lifted by the upper corner fittings (I loading mode); the effect of longitudinal loading on the frame during transportation by the rail transport (II loading mode). Mathematical modeling was performed to determine the longitudinal loading acting on the container in the II loading mode. The determined acceleration is taken into account when constructing the schemes of force factors that arise in the frame. The strength of the frame was calculated using the finite element method, which was implemented in SolidWorks Simulation. The conducted research could contribute to creation of recommendations and developments regarding the design of modern structures of modular vehicles. [ABSTRACT FROM AUTHOR]

The work highlights the results of a study into the dual wedge-shaped wear of composite brake pads for freight wagons. It has been found that the overnormative wear makes the area of a composite brake pad larger in the lower part up to a value directly proportional to the wagon mileage and smaller in the upper part. To assess the braking efficiency of a rail vehicle, a graphical analytical method has been developed; it allows determining the factor of dual wedge-shaped wear of pads depending on the wagon mileage. The results of calculation were verified by comparing two samplings obtained by mathematical and computer modelling. The results of calculation have proven that the hypothesis on the adequacy is not rejected. The results of the study conducted will allow more accurate assessment of the braking efficiency of freight rolling stock to be made, as well as contribute to improving the safety of train traffic. [ABSTRACT FROM AUTHOR]

The publication presents the results of research into the strength of an improved tank container. The tare of a tank container can be reduced through application of composite material for the tank. In this case its mass can be 46% lower than that of a metal tank. The strength of the tank was calculated by computer simulation. The maximum stress occurs in its lower part and is about 295 MPa. The dynamic loading of a tank can be reduced by application of elastic elements in the fittings of a tank container. The reduction in dynamic load is achieved by the elastic friction forces generated in the fittings. The results of mathematical modelling of the tank container dynamics proved the effectiveness of this solution. [ABSTRACT FROM AUTHOR]

The article presents the results of the strength analysis of the chain binder components for symmetry fixing a wagon on the railway ferry deck, taking into account the actual hydrometeorological conditions of the navigation area. The simulation of the wagon dynamic load during the railway ferry rolling was carried out to determine the loads acting on the chain binder. The strength of the chain binder hook was analysed. The calculation results showed that the maximum equivalent stresses in the hook occur in the radial part and exceed the allowable ones by 23%. Therefore, to ensure the strength of the chain binder, it is necessary to comply with the appropriate roll angles of the railway ferry or create measures to reduce its load when rolling. The conducted studies will contribute to ensuring the safety of wagon transportation by sea and increasing the efficiency of rail-ferry transportation. [ABSTRACT FROM AUTHOR]

The work presents the results of a statistical analysis of random processes of the coefficient of vertical dynamics of a passenger car variation. To determine the dynamic performance of cars the tests were running on the tracks of JSC "Ukrzaliznytsia". The main statistical characteristics of random processes are determined for various modes of car movement along curved and straight sections of the track. As a result of statistical processing of experimental data, correlation functions have been constructed that characterize the degree of connection between different time sections of the process of changing the coefficient of vertical dynamics. The obtained indicators of the law of distribution of the vertical dynamics coefficient values, approximating the models of correlation functions and the numerical values of their parameters, make it possible to further simulate the process of loading a passenger car without carrying out lengthy expensive tests. [ABSTRACT FROM AUTHOR]

The mathematical model of a multi-section articulated bus has been improved in the article, which allowed to determine the stability indicators of the two and three-section articulated buses for the Metrobus system. The critical speed for the three-section articulated bus was 28.06 m/s and for the two-section articulated bus - 30.89 m/s. Since the motion of multi-section articulated buses will be carried out on separate lanes with a speed of 25 - 28 m/s, one can assume that the stability of rectilinear traffic of both two and three-section buses is provided. In non-stationary modes of motion with two-section articulated buses, the lateral speed of the first bus decreases by almost 8.5 % compared to the three-section and the second trailer-bus increases by almost 9.5 % compared to the three-section. In this case, the motion stability of multi-section articulated buses can be considered satisfactory, as the lateral accelerations in the center of mass of all sections do not exceed 0.45 g. [ABSTRACT FROM AUTHOR]

The study deals with determination of the dynamic loading on the frame of a tank car with closed composite center sill filled with elastic-viscous filler. It has been found that the measures for improvements can decrease the dynamic loading of the frame by 3.5% in comparison to that of the structure without a filler. The strength calculation of the frame of a tank car is also presented. It was found that the maximum equivalent stresses occurred in the contact area between the center sill and the body bolster; they amounted to about 284.7 MPa and did not exceed the allowable values. The computer modelling of the dynamic loading of the tank car frame was also conducted. The numerical values of accelerations and the distribution fields of accelerations in the frame of a tank car were determined. The results of the calculation showed that the hypothesis on the adequacy was not rejected. The natural frequencies and oscillation modes of the tank car frame were also determined. [ABSTRACT FROM AUTHOR]

It has been determined that the greatest risk of an error in determining the technical condition of the axle box unit in the so-called "zone of uncertainty" is in the impossibility of unambiguously assessing its technical condition. To solve this problem, a model is proposed in the form of an n-dimensional radius vector, which has a direction towards an increase in the probability of failure and a deterioration in its parameters' values. Such a model for determining the axle box unit's pre-failure condition will reduce the risk of errors in decision-making. [ABSTRACT FROM AUTHOR]

Automobiles with internal combustion engine using diesel fuel have large harmful emissions of nitrogen oxides and soot, which affect the health of the population and especially children and carbon dioxide, which is dangerous for the planet as a whole. Biodiesel is used in Europe as an additive to diesel fuel to reduce soot emissions (including carcinogens), as well as to improve the balance of carbon dioxide on the planet. Using the biodiesel in internal combustion engines tends to show higher nitrogen oxides emissions compared to diesel. In this paper, the impact of flame temperature, ignition delay and density on NOx formation of biodiesel and its component for both stationary engine and automotive engine were analysed. Emissions of nitrogen oxides increase with increasing load. In no-load modes, biodiesel shows lower emissions of nitrogen oxides than diesel. [ABSTRACT FROM AUTHOR]

The article presents the results of research into the strength of the hatch covers of general-purpose open wagons. It was detected that strength of the standard hatch covers is not provided in operational loading diagrams. Therefore, new designs of the hatch covers for open wagons were proposed. The results of the strength calculation, implemented with the finite element method, make it possible to conclude that at basic and additional operational loading diagrams the strength values for proposed designs of hatch covers do not exceed the admissible values. The research conducted can contribute to a higher strength of the carrying structures of the bodies of general-purpose open wagons in operation, thus, guaranteeing a higher operational efficiency of the rail transport. [ABSTRACT FROM AUTHOR]

This article is devoted to development of a method for calculating the parameters of an asynchronous motor of an electric locomotive with asymmetrical windings of stator and rotor. A method for determining self and mutual inductances of the stator and rotor phases of an asynchronous motor with asymmetric windings and their relations to mechanical variables is proposed. It is based on comparing two equations of stored magnetic energy, one equation calculated through induction, magnetic field strength and geometrical dimensions and another equation calculated through the parameters of the motor circuits. It is shown that the obtained solutions correspond to the previously existing methods, but they give the additional possibilities in mathematical modeling. The proposed technical solution allows higher accuracy developing of a mathematical model of a drive with an asynchronous motor having asymmetrical stator and rotor windings for studying dynamic processes during the operation of the specified drive, in particular, the drive of auxiliary machines for electric locomotive, where an asynchronous motor with asymmetrical stator windings is used as a phase release. [ABSTRACT FROM AUTHOR]

In order to reduce the cost of designing and manufacturing of the new-generation open wagons, it is proposed to construct their carrying systems from round pipes. In order to exploit the proposed designs of wagons in international rail-water communication, it is assumed that they will be equipped with assemblies for fastening of chain binders. The maximal values of accelerations, as components of dynamic load acting on open wagons, made from round pipes during their transportation on a railway ferry, are determined. It is established that when moving the body in the vertical direction for a wagon located on the upper deck, the maximum acceleration value is 0.84 g, with angular displacement relative to the transverse axis for the extreme from the anchor point of the wagon body - is 0.1 g, with angular displacement around the longitudinal axis for the extreme from the bulwark of the body of the wagon - is 0.24 g. The conducted researches will enable increased efficiency of operation of open wagons through international transport corridors. [ABSTRACT FROM AUTHOR]