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The article is devoted to the analysis of the quality of materials for the manufacture of fasteners for rolling stock. The paper presents the results of studies of parts destroyed during operation that are used for fastening the undercarriage assemblies, spring suspension and impact-traction devices of rolling stock. The purpose of the work is to establish the probable causes of the destruction of parts under the action of static and dynamic loads during movement on the track. The paper describes the methodology and sequence of examination of materials based on the analysis of the chemical composition of metals, the assessment of mechanical properties and the study of the surfaces of fractures of parts. The results of spectral analysis of the metal of the investigated parts, measurements of hardness and analysis of the surface of fractures of the parts are presented, which allowed to establish the possible nature, sequence and causes of their destruction. The results obtained in the course of the research showed that the main reason for the breaks in the fasteners of rolling stock is the impact on them of loads exceeding the tensile strength of the metal. It was found that the brand used in the production of metal does not meet the requirements of the normative-technical documentation for the product and is not intended for the manufacture of fasteners. Thus, the findings confirm the need to tighten the quality control of materials used in the manufacture of fasteners for rolling stock, and can be used in machine-building enterprises specializing in the production of components and spare parts for railway rolling stock. The main conclusion of the work is the need to use in the production of fastening parts of the responsible components and assemblies of rolling stock, structurally reasonable steels and alloys.

The article describes the study of the mechanical characteristics of polymer insulation, in particular the hardness of the insulating lacquer layer with a different methods of drying it. The influence of the hardness and elasticity of the dried impregnating material on the reliability of the insulating structures during the operation of electrical equipment of the traction rolling stock is analyzed. A device has been created and presented that allows for a simple measurement of the hardness of the varnish film on a pre-selected object of study, which was the insulating finger of the bracket of the brush holder of an electric locomotive traction motor. The process of measuring hardness and results for three groups of insulating fingers are presented: insulating fingers without coating by an impregnating compound (press material); impregnating material, sealed by convective method; impregnating material baked by thermoradiation method. On the basis of the obtained practical results, the effect of the energy supply on the curing process when performing drying by the convective and thermoradiation methods is explained. Also presented are photographs of an electrically insulating lacquer layer from an electron microscope, which allow the microstructure to be evaluated for the presence of gas inclusions, which have a negative effect on both mechanical and electrical indicators of polymeric insulation. A study was made of the relationship between the parameter of electrical and mechanical strength. On the basis of experimental data, the dependence of the breakdown voltage on the hardness of the insulating lacquer layer was constructed.

Annotaion. The relevance of carrying out research works on improving the regulatory and methodological base in the development of promising railroad rolling stock structures with the use of new structural materials with nonlinear properties during deformation (physical nonlinearity) is substantiated in the work. The possibility of using the finite element method (FEM) procedure for creating such constructions is considered. Dependence of stresses on deformations is approximated by a cubic parabola. This made it possible to obtain generalizations of the well-known relations and algorithms of the classical theory of FEM with a nonlinear relationship between stresses and deformations. The proposed technique was tested in the evaluation of the stress-strain state (SSS) of an aluminum gondola car under various standard loads according to the 1st design mode. The effect of physical nonlinearity on the SSS of a spiral beam of a freight gondola car of aluminum alloy AMg6 was estimated. The calculation of the stresses generated by the action of a longitudinal force with eccentricity shows that the stresses in the nonlinear approximation are 13% lower than the corresponding stress values obtained by calculation in the linear theory. The results obtained can be recommended for the development of pilot projects of new structures optimized for weight and strength characteristics.

Results of mathematical modeling of determination of character and the law of change of forces and tension arising in the field of contact of interacting bodies on the example of dynamic contact at impact of an elastic sphere about motionless, absolutely rigid plate are presented in article, at its flat movement. The received results can be used at calculations of contact forces and material tension in a metalwork at shock influences.

Solidifying transportation of goods by rail, namely, tank wagons is accompanied a number of difficulties. These include: lowering the temperature of the transported oil, accompanied by the growth of its viscosity, the inability to quickly discharge, change in performance of transported oil products, an increase in idle tank cars. The analysis of the cooling rate of the goods transported, depending on the size and thickness of the insulating layer. Introduced formulas show that the presence of the heat-insulating sheath is cylindrical vessel radius deviation from the optimum value. When this thermal insulation reduces considerably the heat transfer coefficient in the surrounding area and to accelerate the discharge process.

The issue of optimizing the use of lubricants to reduce the in-intensity wear of the wheels of traction rolling stock is considered in the work. The purpose of the work and the test objects are defined. The types of tests, their procedure, short description of tests, and compliance with the technical assignment and technical requirements are presented. Design work was carried out on the development of solid antifriction elements for lubricating the ridges of locomotive wheel pairs (hereinafter referred to as TAEL rods). Bench tests were carried out on a universal friction machine 2168 UMT «Unitrib», which models the contact interaction of the wheel with the rail when applying solid lubricant to the wheel ridge. The linear wear rate of the lubricating element and the friction moment were determined. Explutation tests were carried out on the basis of traction rolling stock of the series VL80, 2TE25KM, ChME3. Such indicators as average intensity of development of cores of TAEL and lubricant cores and average intensity of wear of crests of wheels were defined. The results of laboratory bench-out and operational tests of TAEL rods were obtained in accordance with the order of admission of lubricating materials for wheel-rail contact for use in locomotive combs operated on the railways of the Russian Federation. Operational tests of traction rolling stock were carried out at the landfills of the North Caucasus, South-Eastern and Volga Railways. During the performance test period, the following indicators were monitored: assessment of the impact of TAEL on the wear of co-forest steam ridges, assessment of the actual resource of TAEL production, assessment of the functional capabilities of TAEL rods. According to the test results, the developed TAEL rods received permission to use Russian Railways for the infrastructure. At the same time, the wear rate of the ridges of the wheel pairs of locomotives equipped with TAEL in comparison with the standard rods decreased to 50 %.

The work is devoted to the consideration of the possibility of using composite materials with an aluminum matrix in the design of electric transport pantographs. Currently, there is a tendency to increase the speeds of electric transport. This fact requires reliable and high-quality current collection, which can be achieved by reducing the mass of the current collector design, including through the use of composite materials. The possibility of using composite materials in parts and assemblies of current collectors operating under conditions of increased current loads and at high speeds of movement and the mechanical characteristics of the traditional ones used in the carriage design and the composite materials proposed for use are analyzed. The design of a carriage of high-speed electric rolling stock has been developed, in which an aluminum matrix composite material was used as a structural material. Statistical modeling using the finite element method in the SOLIDWORKS Simulation software package was performed. Comparison of the strength characteristics of carriage assemblies made of traditional materials and aluminum matrix composite showed the possibility of reducing their weight in the case of composite use without reducing the strength of structural elements. The static characteristic of the carriage in which the composite material was used coincides with the static characteristic of the carriage made of traditional materials, which confirms the possibility of using an aluminum matrix composite without making significant changes to the carriage design. To evaluate the dynamic characteristics of the composite carriage and its effect on the dynamic characteristics of the pantograph, modeling was carried out using the methods of multibody modeling of SOLIDWORKS Motion. The obtained simulation results indicate an improvement in dynamic characteristics when using composite materials, which has a beneficial effect on the reliability and quality of current collection.

The technique and algorithm of definition of consumption rates of materials on the current maintenance of a way depending on freight density, the passed tonnage, the plan and a profile of sites of a way, axial loadings of a rolling stock is given. Standards are developed on the basis of the analysis of the existing normative documents, statistical data from forms of primary accounting of PU-74 of the consumption of materials, annual reports of linear sites and other sources. Depending on service conditions standards are determined by analytical dependences and the correcting coefficients.

The problems of optimization of organization of maintenance and repair of locomotives. The article presents new approaches for calculating the norms of spare parts and materials. Models of vehicle systems consisting of a fleet of operated locomotives are given, taking into account all conditions.

Issues related to the wear of the rail and wheel tread of a locomotive are always of great interest to both operational services and scientists. Knowledge of the influence of technical and operational factors on the intensity of wear of the materials of the contacting bodies would save material and financial resources. The proposed article is devoted to determining one of these parameters, namely, the depth of indentation of the material of the rail head into the material of the wheel rim flange. The force interaction of the bandage crest and the rail head occurs mainly at the level of irregularities in the contact area. The wear of the material of the contacting bodies will be determined by the depth of penetration of irregularities in the contact area and the speed of relative slip. An important parameter for assessing the magnitude and nature of wear is the relative penetration depth of the contacting bodies. In this case, the magnitude of the collapse of one of the contacting bodies is equal to the depth of penetration of another body into it. Calculations of the main radii of curvature of the surfaces of the rail head and bandage crest at the point of their contact are made, and the dimensions of the contact area are determined. As a result, expressions were obtained for calculating the depth of mutual penetration of the materials of the shroud crest and the rail head. The rail head material has a deeper penetration into the shroud tongue material. The force contact between the bandage crest and the rail occurs mainly within the limits of plastic deformation of their materials. Formulas are obtained for determining the magnitude of the approach of the contacting bodies and the highest normal stress in the contact zone. An estimate of the values of the collapse of the material of the rail head and the bandage crest was made, which makes it possible to judge the percentage of their wear. With force contact, the wear of the wheel rim flange is much higher than the wear of the rail head.

Article considers modern shumo-vibroprotective materials for car building. Security measure of the person from vibration in cars are constructive improvements, applica-tion of means of external vibroprotection by uprugodempfiruyushchy materials and devices which take place between a source of vibration and the person, and also continuous control of serviceabil-ity of cars and their timely scheduled preventive repair as in use and wear there is an expressed strengthening of vibration. Considering that constructional features of cars provide compliance "To health regulations on the organization of passenger traffic on railway transport" in the course of formation of structures and at operation of cars there are the technical problems caused by aging (technical wear) cars, a detsentrovka, defects of a way, etc. that leads in practice to deterioration of an acoustic mode of internal rooms of cars. Comparative researches of sound-absorbing properties of a material from aramide fiber and ecologically safe material NOL-1A(B) are conducted. Decrease in noise levels in rooms of cars, due to use of modern materials is experimentally established. NO-L-1A use in a design of air ducts of cars of locomotive draft allows to reduce considerably noise level in rooms, and to raise ecological characteristics of cars.