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The analysis of the influence of operating modes and the development of the residual life, expressed through thermal wear of the insulation of the asynchronous traction motor. The research subject is to obtain new patterns of change in the residual life of the stator winding insulation, which make it possible to determine the specific life of the winding for each mode of the asynchronous traction motor. The research aim is to create a system for determining and assessing the residual life by developing methods and technical means of monitoring and comprehensive diagnostics, as well as theoretical justification using the method for determining additional thermal wear of the stator winding insulation, taking into account the combined effect of the starting transient process, the long-term allowable load schedule and the maximum allowable temperature values. To determine and assess the possible residual life, the method of sequential influence of starting transients, maximum permissible load curves, as well as long-term overloads at the maximum permissible temperature, taking place under various operating factors during the movement of electric rolling stock, was used. The expediency of determining the function of uneven resource development, which has a monotonic character and is approximated by a linear double exponential and exponential functions, is shown. Specific proportionality coefficients are experimentally determined, which characterize the decrease in the dielectric strength of the insulation with sequential alternation of maximum and long-term permissible loads and maximum permissible temperature values, followed by obtaining an analytical relationship that predetermines the insulation resource. It is shown that the determination and assessment of the residual resource under typical modes practically makes it possible to clarify the timing of preventive measures and predict the expected duration of accident-free operation and forestall the premature failure of the asynchronous traction motor.

Principal directions for increase of locomotive operating efficiency are determined in the article based on statistical estimates as per data on the main domestic locomotive series. Work ratio is suggested as universal indicator. It is demonstrated that in addition to locomotives' reliability enhancement, increase of the trains' haulage management system efficiency is also a large reserve. It is proven that the number of locomotive units can be reduced at least by 2,000 thous. units.

In article the question about possibility of extension of service life of carriage wheels by influence on technological parameters of restoration of their driving profile is considered. The correlation analysis of statistical data on volumes of machining and the size of defects on a driving surface of the wheels coming to repair is made. The mechanism of purpose of an allowance for machining of a driving profile of a wheel which will allow to reduce an unreasonable consumption of metal of a rim of a wheel in shaving is offered.

The article assesses the state of the market of transport and cargo services in Uzbekistan, considers the problem of scientific justification of the rational placement of cargo facilities in the country. Analysis of the problems of transport services has shown that freight traffic flows have spread out, negative trends have manifested themselves in the form of regular growth in the cost of fuel and energy resources, tightening of regulatory requirements, growth of customs duties, sanctions in the form of cancellation of previously introduced benefits, and more. However, such indicators of rail freight transportation as the range of container transportation and average travel time are stable in rail traffic, i. e. the diversification of the cargo base and the tendency to full capacity utilization take place. Separately, it should be noted that rail transportation interacts with other transport industries - automobile, air, sea, river and other modes of transport - as partners, not as competitors - multimodal freight transportation is widely developed, special logistics agencies operate to ensure the organization of uninterrupted work during freight transportation. Uzbekistan's railways need to be reformed, and possibly restructured. At least, private capital funds are already being attracted to the system of private carriage operation. The article describes the scientific methods of analysis and synthesis, classification, mathematical statistics used in the study. A roadmap of qualitative transformations for the reorganization of the transport and cargo industry has been proposed, which will bring positive results for the transport infrastructure as a whole.The results of the study will further reveal the capabilities of terminal networks capable of providing in a short time the delivery of large volumes of necessary cargo to domestic and foreign markets, the uninterrupted functioning of the necessary infrastructure for the placement of cargo facilities on the railway network. The object of the study is the state of transport infrastructure with a decisive role in trade.

The technique of a prediction of coefficient of Hurst on the basis of various ways of a prediction is offered. For a choice of a method of a prediction errors of underestimation and revaluation are entered. It is shown that if not to consider fluctuation of value of coefficient of Hurst, the demanded parameters of a multiservice network, the allocated resources of a network used for calculation or will be insufficiently for high-quality service of the arriving traffic (that is QoS indicators will worsen), or resources of a network will be inefficiently used.

The need to apply various methods for predicting the technical condition of reinforced concrete supports of the contact network is currently a necessary condition for ensuring the safety of train traffic. Such a need arose due to the presence in operation of supports with extended service life, in the absence of a reduction in loads, without the presence of various kinds of redundancy. The article describes a method for predicting the technical state of the supports of the contact network. Solving the problem of exploitation, which consists in the fact that it is rather difficult to reveal the system of failures of the considered object of exploitation, under the influence of many factors. The probability of finding the contact network supports in a certain state is expressed through the statistical properties of the contact network supports, based on the change in the carrying capacity

The factors affecting the operational reliability of the assembly platform of a rail service car maintaining the repair and installation on the railways are considered in the paper. An assessment and analysis of a system of quantitative indices of reliability is performed, the methods for their separate determination by mechanical equipment and hydro and electrical equipment is described. The strategy of maintenance and repair combined with the use of methods and means of a modern diagnostic system is considered; it ensures the estimation of the object reliability during its design, operation and repair.

The analysis of functioning of difficult transport systems is provided in article, the basic principles of use of simulation modeling in the organization of transportation process on railway transport are characterized. The method of creation of object-oriented model for the description of dynamics of interaction of cargo station and a way of uncommon use is considered.

By the author it is offered complex programs of association in uniform system of all processes of life cycle of locomotives, promoting reduction of the expenses connected first of all with operation and service of locomotive park JSC RZhD. The main indicator this complex the system is the level of readiness of a technical product determined by an availability quotient. The developed methodology will allow to pass from technology of fixation of technical refusals, with the subsequent identification of their reasons and carrying out recovery work, to the technology of forecasting and the prevention of these refusals based on a constant control of technical condition of locomotives and forecasting of a stock of a resource in the Online mode.

The purpose of the work is to analyze and assess the structure of economic development and the impact of the «economic space» on railway transport in Uzbekistan, to consider the use of container block train technology. Scientific methods of analysis and synthesis, classification, mathematical statistics, economic analysis, mathematical technical modeling are used. The following results were obtained. The dynamics of the development of cargo transportation in Uzbekistan is assessed on the basis of GDP data. The volume of provided transportation and the use of modes of transport by the volume of shipped products is considered. Of these, the number of goods shipped in Uzbekistan from railway transport, the dynamics of the volume of transportation of certain types of cargo in containers. According to the dynamics of the growth of cargo transportation, a decrease in growth was revealed in 2020 and associated with the pandemic, but in general there are steady growth rates. It is concluded that along with the ongoing work on the renovation and reconstruction of railway tracks, it is necessary to take measures to optimize the entire chain of cargo transportation by containerization, so the use of block train technology. The practical significance of the results of the study follows from the fact that the analysis of the development of transport infrastructure revealed a sharp decline in the results of transport at the end of 2019 - 2020 due to the pandemic, but at the same time, there is a reduction in the «economic space» by improving transport infrastructure, simplifying transit and customs clearance procedures, increasing transit volumes and regional trade, therefore, the logistics transportation market in the republic will grow at an accelerated pace in the coming years. Mass use of containers with the use of block train technology, so. the collection of containers from the port rear terminals, where the formation of batches of containers takes place, and their accumulation in the volumes required by the buyer for transportation by rail can also be a solution to the identified problems.

This article contains information on the main pollutants and weeds on the railway. In the article the questions of the intensity of the contamination of the broken stone ballast. Specified criterion for assigning secondary and preventative maintenance of way in accordance with the technical specifications. Given reasons for the increased intensity of the contamination of the ballast in the first year of life. The analysis contamination of the broken stone layer in areas the Trans-Siberian Railway and the Medium-Siberian Magistral. The Trans-Siberian railway is considered towards Chelyabinsk - Karbysheva - Novosibirsk, the Medium-Siberian Magistral in the direction of the Input - Irtysh - Medium-Siberian. The analysis was conducted based on the data of geological investigations design and survey institutions and to schedules of repairs for the West Siberian infrastructure Directorate. For ease of estimation of the parameters of weeds the resulting material was consolidated into a single table. Based on the table were revealed of the according contamination of crushed stone ballast thickness, ballast layer, from the conceded tonnage and length of operation in years. The article describes the structure of the pollutants by particle size, in terms of pass excess tonnage. Indicated levels of contamination of crushed stone ballast at different values of the missed tonnage (700 million tons 1200 million tons and 1400 million tons). Additionally, this work was determined the average level of contamination of the ballast particles less than 25 mm, 5 mm and 0,1 mm) and obtained a limit value of the allowable clogging the broken stone ballast more than 30 percent. The result revealed the need for reducing the contamination of the broken stone ballast by conducting a deep cleaning.

The article deals with the locomotive lifecycle problem at vehicle technical maintenance and repairing service. It proposes to encapsulate the statistic methods into the automatic locomotive depot control system basing on the example of management with the minimum stock spare parts level. In such a group of companies as "Locomotive technologies" the efficacy of maintenance and repairing technological processes is improved by creation and implementation of the information management control system "Network diagram" into the locomotive depot service. Its implementation was started in 2016 and should be completed by the end of 2017. In practice methodological approaches of international (ISO) and national (GOST) standards of management quality and reliability, lean manufacturing and statistic methods of management in conditions of locomotive depot service are proposed to be used basing on the principle of "Built-in quality". In this case logical constructions, algorithms and formulas are encapsulated into “Network diagram” software significantly reducing the training level demands of the depot personnel. The article also proposes to control the minimum level of stock spare parts in the locomotive depot in terms of “Network diagram” software through encapsulation of probabilistic-statistical methods of minimum stock calculation according to the data on intensity of parts consumption and the time of their delivery to the depot.

The article presents the results of the development and implementation of a method for controlling the technological processes of repairing locomotives based on network planning. The methodology allows you to track online bottlenecks during current repairs and reduce the duration of the critical path by varying the time indicators of events and works, using the aggregate-nodal repair method, redistributing resources between critical and non-critical works. The developed methodology is based on the adjustment of basic repair networks, taking into account the workload of process equipment and repair personnel, the availability of spare parts and materials, the need for unscheduled work during the planned installation of a particular locomotive for repair. This approach was implemented within the framework of the automated control system (ACS) «Network Schedule» and provides control and adjustment of the implementation of technological operations according to the indicators of technological preparation of repairs. An algorithm has been developed for determining a generalized performance indicator when assessing the quality of functioning of an automated maintenance and repair control system for a locomotive in service locomotive depots.