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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.

This article contains results of a preliminary study of the parameters of the laser triangulation sensor in the context of its application to control of a technical condition of details of the car. The main aim of the study is the experimental determination of the limits of applicability of the sensor to monitor the real sample detail of the new design freight car on the example of 18-9855 bogie parts. By the experimental methods where established the threshold limits of applicability of the given sensor, its properties and application features for dimensional control. Also where established limit angles of the distance measurement at the maximum setting of the speed sensor, the actual focal point of the transducer. The analysis of the obtained data allowed authors to make an optimal scheme of automated measurement machine of portal type for control of the size and shape of parts of the car. The results of the work is possible to use when designing automated systems and equipment for dimensional inspection of parts during manufacture, repair and maintenance of railroad cars and other vehicles.

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

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.