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The experience gained in the operation of high-voltage vacuum circuit breakers VBO-25-20/ 630UHL1 indicates an incorrect assessment of the mechanical resource of its individual components and elements. Despite the repeated improvement of the design of the main switch drive, applicable both as part of the new «Ermak» series locomotives starting from number 1000 series, and in earlier numbers, the dynamics of malfunctions continues to persist to the present time. One of the most important elements of the main switch is a latch designed to hold the elements of the drive mechanism in the on position, the failure of the latch entails the failure of the entire section of the locomotive. The article considers three latch upgrades previously proposed by the manufacturer, a kinematic scheme of the drive with a vacuum arc-extinguishing chamber of the switch is developed, the parameters of the preload and trip springs in the drive are calculated, the forces operating during operation are determined. On the example of the latest modernization of the latch using the finite element method in the SolidWorks Simulation software package, a strength calculation was carried out, according to the results of which the stresses arising in its design were determined. As a result of the analysis of the finite element model, the forces critical for the structure are determined, a graph of the dependence of the structural strength margin and the maximum stress in the structure on the acting forces is developed. According to the results of the study, the force at which the most favorable value of the safety factor is provided is determined, for which it is proposed to reduce the critical force by changing the parameters of the compression springs and disconnecting the drive of the arc extinguishing chamber. A loading diagram with the drawing dimensions of two modified springs has been developed.

In this paper analyzed the design of cast and weld side frames three-piece bogies. The directions of further improvement design side of a bogie frame.

One of the many topics on which he worked V.V. Lukin in end of his life, was to improve the cast parts bogies freight wagons using the finite element method. In this paper the authors shows that the method of finite element analysis of the stress-strain state of two of the most essential parts a three-element bogie freight cars to further improve the their design.

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.

The article studies comparing the effectiveness of using thermoradiation and convective drying methods insulation windings of electrical machines of traction rolling stock, impregnated with various modern varnishes and compounds at their factory and depot repair. Objective factors in the comparison methods are parameters such as temperature class, electric strength and cementing capacity. The author substantiates advantage thermoradiation method over convective.

The article is devoted to continue presenting the results of experimental studies on the identifi-cation of rational modes of IR energy supply in encapsulation technology insulation windings of electric machines (EM) of traction rolling stock (TPS). In this paper, published the results of com-paring the effectiveness of the use of various oscillatory modes of infrared (IR) energy supply in the process of winding insulation encapsulation the frontal parts armature winding of the traction mo-tor type NB-514B electric locomotives series "Ermak" on the process plant at their depot and fac-tory repair. In studies to identify rational oscillating modes IR energy supply option duty cycle remained unchanged for the existing design of the generator of heat radiation technological installation, and changed only option cyclical, characterized by changing the speed of rotation of the armature trac-tion motor on the plant corresponding to 5, 25 and 50 Hz when the drive installation works from the frequency converter. The process of encapsulation was carried out first only short-wavelength radiation generated incoherent halogen emitters, then only at medium-wavelength radiation generated pulse ceramic radiators, and finally - with alternating heating medium short- and medium-wavelength radiation, i.e. with these two types of emitters in the spectral-oscillating mode IR energy, on which is currently obtained patent for the invention. For comparability of experimental studies same dose irradiation of segments frontal part of the armature windings of the traction motor type NB-514B electric lo-comotives «Ermak». Objective factors when comparing encapsulation modes to identify the most efficient are pa-rameters such as dielectric strength (the value of the breakdown voltage insulating tape) and ce-menting capacity.

This article contains results of experimental studies on the formation of corrosion products as a result of aggressive environment and electric currents action on the reinforced concrete structures. There are discussed a method of creating models with artificial electrocorrosion under conditions close to real working. The results of testing models using the X-ray method and modeling their strength characteristics are presented.

The deterministic evaluation of the durability of railway rolling stock structures according to fatigue safety factors, established by regulatory requirements, does not fully take into account the random nature of loads that cause the accumulation of fatigue damages, the operation rate (operating time), does not allow to evaluate the operating life and its depletion over the service lifetime. At the same time, with the development of heavy and high-speed traffic, as well as due to the introduction of technical regulations, the task to evaluate and substantiate the assigned service lifetime and operating life of railway vehicles are becoming more important. The subject of the study, the results of which are presented in this article, was the fatigue strength of elements of locomotive basic parts. The purpose of the work was the prediction of their limit state by the operating life of critical elements. In the present work, design and experimental studies have been performed with running dynamic and strength tests of the locomotive in the entire range of operating speeds of its running, determining the stress-strain state of structures using strain-gauge methods, calculating safety factors with the probabilistic estimate of the fatigue strength of parts. According to results obtained, the influence of the operation loading performance on the fatigue strength margin and its depletion during the element operating life is shown. According to the results of this work, it can be concluded that main indicators of the strength, operating life and service lifetime of the locomotive make it possible to compare and link their key parameters for the subsequent analysis, substantiation, rating and control of safe operating life of railway equipment.

The article provides for the design features of pantographs of an electric drive train, a system of movable frames, which are made in the form of two articulated rod-type levers. Single-lever pantographs are distinguished by improved mass-dimensional indicators, which allows them to be used in the cramped conditions of the roof space of two-system electric locomotives. This requires high mechanical characteristics, as well as the need to use structural materials of increased strength, precision processing methods and high precision during assembly. It becomes especially important to control the transverse and advanced cruelty of the moving frame system during research, periodic and qualification tests, as well as during operation. The article describes a methodology that allows conducting research with a high degree of labor intensity, increasing the speed of measurements, and reducing the influence of the human factor.

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.

The article discusses the possibility of extending the service life of passenger cars. The analysis of the state of the passenger car fleet has established that the rate of replenishment of reserved cars has been reduced by more than 40 % over the past 10 years, therefore, it is possible to ensure coverage and replenishment of the retirement of rolling stock of this type after the expiration of the standard service life only by extending the service life of existing cars by carrying out capital repairs with the establishment of a new standard service life. When analyzing the power frame of a reserved seat passenger car, it was found that the greatest static and dynamic loads are perceived by its center beam. It is precisely because of the stresses arising in it that an assessment is formed of the further possibility of operating a car both during its life cycle and further use in diagnostics for the possibility of assigning a new service life to it during overhaul repairs. Studies of a number of elements of center beams cut from passenger cars that have expired the standard period have established that the main characteristics of the metal meet the requirements of safety standards, this indicates that the safety margin and resource inherent in them has not been fully depleted. In the study of the presence of residual stresses that have arisen in the elements cut from the ridge beams, depending on the depth of etching carried out according to the method of N. N. Davidenkov in accordance with the TSNIITmash methodology, the most vulnerable and dangerous places of corrosion that require more careful control during the car maintenance and scheduled preventive repairs were identified. In order to reduce the development of residual stresses and the corrosive effect on the load-bearing frame of a second-class car, recommendations and technological operations have been developed for strengthening the ridge beam by the method of shot-blasting with the formation of a uniform fine-pored structure, which ensures uniform application of paint and varnish coating.

The results of the study the strength characteristics of loess loam under triaxial when exposed vibrodynamic load of high-speed trains. Research carried out on triaxial vibration, based on the principle of operation of the plant simulation vibrodynamic exposure to periodic changes in hydrostatic pressure in the working chamber triaxial. The experimental values of specific cohesion and angle of internal friction, and the values of their relative decline under the influence of vibrodynamic load.

In research consider a methodology the remaining life assessment of rail with fatigue crack in lower flange. Obtain the stress intensity factor equations for crack size and kind of stress: bending stress, thermal and residual stress. Make up an fatigue strength analysis of rail P65 and under different conditions of loading and remaining life calculation of damaged rail when given conditions of loading. Submit a assessment evaluation rail reinforcement in cyclic crack growth rate.

The reinforcement of a soil subgrade by solidifying grouts injection, outside the limiting dimensions of train movement, can significantly increase the cost efficiency and manufacturability of strengthening. The paper suggests the most appropriate methods to strengthen the subgrade depending on the stage of defects and deformations development.