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The article presents the results of studies of the effect of material properties and wheel failures on the process of their machining on the on the car wheel lathe. Developed by complex criterion that takes into account the effect of various factors on the allowable cutting speed. The proposed method for assessing the machinability of cutting wheels through additive criteria. The quantitative characteristics of the machinability of cutting are obtained, taking into account the macroscopic imprecision of the geometric shape, defects in the thermomechanical interaction of the wheel, brake pad and rail, surface defects of the rim, work hardening and the presence of zones of increased hardness. The results can be used in the development of methods to reduce the consumption of carbide cutting tools for machining parts of rolling stock with operational defects.

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.

Article is devoted to one of actual problems – to definition of the rational hardness ratio of wheel and rail. The mathematical model of wear process of friction pair «wheel – rail» is developed. Results of researches on intensity of wear process of wheel and rail are presented.

The aim of the work, the results of which are presented in this article, is to a study of the impact of physical and mechanical properties of rail steel on the parameters of the spectrum emission. The experimental results were obtained by method of atomic emission spectroscopy (AES) in argon. Performed quantitative analysis material of the rail steel and built a multi-dimensional graduations of the description of the spectral lines correlate with changes in the hardness of steel. The results can be used to extend the capabilities of devices atomic-emission spectral analysis

Article is devoted to actual questions of research of microstructure,physic-mechanical and tribological indicators blankets of friction couple "ring-sleeve of cylinder" under laser processing.Analysis of base defects of elements of cylinder-piston group of internal combustion engines,methods their reduction and rise of tribotechnical characteristics are conducted.Notes that different kinds of thermos and chemical thermal processing of working surface of link are most effective means of rise of wear resistance of couple "ring-sleeve of cylinder".Using of perspective technology of laser thermostrengthening is offered with this target.Offering technologies find greater application in automobile and technics of agricultural purpose. But purpose of ICE in aviation industry due to their specific exploitative and specific design features is limited.At the same time,they may have important practical meaning. Different variants of laser modification of surfaces of coupling in the context of CPG of aviation engine of ASH-62IR are offered and analyzed in article. Data of microstructural analysis of blanket,indicators of microhardness and wear resistance are adduced.Short description of tribotechnical laboratory-scale plant and methodic of conduct an experiment on base of comparative analysis of findings is given.Wherein tribotechnical indicators are compared with results of metallographical researches and physic-mechanical properties of modification layer,in particular with indicator of microhardness. Conduct of tribological researches determines that rise of indicator of wear resistance of friction couple "ring-sleeve of cylinder" observed at all researching regimes of laser effect with acconting of identified border conditions of processing for both elements of coupling.Maximum value of wear resistance is observed at laser thermostrengthening of both surfaces of couple on critical levels of density of laser energy.These levels do not case of appearance of microcracks in blanket.Wherein wearing qualities of modification surface of cylinder sleeve may increase by 4,5 - 5 times and wearing qualities of piston rings more than 3 times. Theoretical bases of mechanism of wear of thermos thermostrengthening surfaces which illustrate kinetics of increase their wear resistance in result of formation of microstructure of special blanket with increased bearing capacity,microhardness and improved conditions of wear of modification layer.Experimentally validated that the greatest wear resistance is observed in the friction elements at their mutual modifying their surfaces.

The cranking of the bandages in service leads to an earlier replacement of the bandage than the pawned resource, which entails both an increase in maintenance costs and a long, simple locomotive for repair. The article shows the main factors that have a significant effect on the strength of the «wheel center - bandage» connection. Particular attention is paid to the mechanical properties of materials. The calculation of the reduction of the contact pressure from the heating of the bandage has been carried out, both for the new and for the worn out. New materials for manufacturing of bandage wheels are considered. It was found that the hardness of the materials can have a significant effect on the strength of the bandage fit to the wheel center. Preliminary calculations of the influence of hardness on the strength of the joint are carried out.The analysis of the influence of the mechanical properties of banding wheel materials on the strength of the joint can be used in the improvement of new materials in the manufacture of bandage wheels and in the development of technology for the formation of wheel sets of locomotives, which in turn will improve the efficiency of wheel sets of lo-comotives.