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This article presents an analysis of the reliability of asynchronous auxiliary machines (AAM) type NVA-55 electric locomotives «Ermak» in custody Art. Vihorevka (East-Siberian Railway) and Art. Smolyaninovo (Far Eastern) for the 2009-2011 year. Identified the weakest in terms of reliability components and analyzes the main types and causes of these types of faults AAM. One of the research objectives reliability AAM type NVA-55 is to determine the mean time between failures that could prevent failures in the organization of maintenance and repair, as well as extend the life of the machine. Defining the objective mathematical expectation of failure AAM for effective correcting the overhaul life mileage is not possible, since failures are largely have random and not permanent.

In order to extend the service life of electric machines traction rolling stock has been proposed recovery technology insulation using infrared energy, will improve the quality of insulation in terms of the breakdown voltage and hardness. This article analyzes and estimated of experimental studies conducted in two different meaningful of the work in this direction. Presents an analysis these works in terms of distinctive features and conclusions of the pilot studies. According to the analysis formulated a new hypothesis about the need to address when capsulating the insulation and its elasticity. Also set new directions for future research.

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.

Constantly conducted studies of the reliability of electric equipment of traction rolling stock have shown that the most vulnerable element is the insulation design of the windings of power equipment, especially traction motors. Existing methods and means of restoration and repair of insulating structures of windings of traction motors of modern electric locomotives, based on drying polymer insulation in convective high-power electric furnaces, are energy and time-consuming. This technology has not undergone significant changes for over 50 years. In order to extend the polymer insulation life of electric vehicles of traction rolling stock, an insulation drying technology using thermal radiation was proposed that reduces the cost of electricity for repairs and increases the drying speed by reducing heat loss. The article is devoted to the design of a new device for drying the insulation of the windings of the magnetic system of the skeleton of the backbone of the electric locomotive traction engine by a rotating thermal field. The analysis of works and conclusions based on the results of theoretical studies related to mathematical modeling is presented. As a method of mathematical modeling, the finite element method was used in the work. A simplified 3D model of the winding of the core magnetic system with infrared emitters was created. According to the results of finite element mathematical modeling, temperature fields of heating the polymer insulation of the windings of the core of the traction motor were obtained. Based on this calculation, the work selected the optimal design parameters of the proposed device that provide the minimum energy costs for various sizes of the skeleton of the traction engines. Based on the proposed device variant, an application for a patent for a utility model has been filed, and this prototype is being assembled on the basis of the Ulan-Ude locomotive and car repair plant, a branch of Zheldorremmash JSC. New directions for further research are also set.

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.

The main damaged knot of traction electric motors of a traction rolling stock is isolation, namely in the field of the basis of front part. The imperfect system of isolation in face part of front windings results in humidity. Also the increased intensity in this zone is the reason of low reliability. Authors propose the system of local insulation encapsulation energy of infrared radiation as life extension activities of electrical machines.

This article analyzes the conditions of work of asynchronous auxiliary machines (AVM) electric AC, mainly operated on the network of the East-Siberian railway. Presented the experimental data on the dependence of the motor phase currents ANE 225 locomotive VL 85 on the value of the supply voltage, the duration of start - MC with an induction motor, depending on the voltage of contact network, change the moment of resistance of the compressor depending on the air temperature. Reviewed the features work of the AVM, in particular, their alternate launch of its own needs winding of traction transformer. As a result of systematization of operating conditions affecting the isolation of AVM in order to optimize the parameter tracking their rate of wear, which resulted in the allocated two major factors of aging insulation overheating and vibration, and one factor that increases the probability of failure, regardless of the degree of aging of insulation - it moisturized

Currently, in the brake system of operated cars, there is a problem of lack of brake pressure on the wheel, which is necessary for the movement of the train at a set speed in accordance with the regulatory documentation. This is due to the tendency to increase the mass of trains and the maximum load of cars with a constant tare weight, which requires an extended range of pressure control in the brake cylinder by an air distributor or auto mode, depending on the load of the car. To solve this problem, calculations were made of the braking coefficient of cars equipped with air distributors № 483, which showed that the freight car was not equipped with brakes to run as part of a train at a set speed. In the course of engineering studies, it turned out that increasing the spring rate of loaded and medium modes can increase the adjusting range of the air distributor and partially solve the problem of lack of brake pressure. Thus, it is proposed to recalculate the stiffness of the adjusting spring. Calculations of the rigidity of regular and proposed springs were made. The braking coefficient has been recalculated, taking into account the increased spring constant. As a result, this coefficient has increased, which makes it possible to remove speed limits. The proposed method for upgrading the air distributor can be carried out on all types of repairs, which facilitates the implementation process.

In this article, the currently existing methods for determining such a technical parameter as the sliding friction coefficient were considered. The coefficient of friction is one of the main parameters characterizing the operation of tribological pairs of any engineering system. Stable and efficient operation of tribological pairs in such systems, along with high strength and fatigue characteristics, are not only the basis of safety, but also a promising direction in terms of economic benefits in the design and operation of various devices and systems. Accordingly, this area of research is very relevant for the railway industry, and for railway rolling stock in particular. This is caused by a large number of friction pairs in different nodes of passenger and freight cars, locomotives, ensuring safe and uninterrupted movement of rolling stock as a whole on iron drogs. Tribological processes are important both directly during movement and during braking processes. In this matter, the factor of determining and analyzing the sliding friction coefficient comes to the fore. One of these friction pairs is the «pad-wheel» system, which is the executive body of the braking system of a railway train. Optimization of contact in this system is one of the determining factors for the growth of braking efficiency during braking, increasing the working life of the elements of the friction pair, reducing the likelihood of defects. The search for new approaches to the study of friction issues is a direct catalyst for scientific and technological progress in the engineering industry.