The article briefly describes the technical solution for the use of specialized fiber-optic cable embedded in ground wire (OPGW) on the sections of electric Railways AC. The technical solution is to combine in a single conductor functions return conductor and fiber optic communication lines. Are given the relevance of such decisions and some peculiarities of its implementation. The main part of the article examines to the selection options return conductor with combined functions. The article describes the theoretical dependencies for the combined selection of the conductor based on the thermal resistance criterion. As one of the main passport parameters of the OPGW cables is the section of the metal component, the percentage of their content and the variation percentages are used in calculations to determine the electrical resistance of the cable and the magnitude of the permissible current. This approach allows to determine the parameters of the cable based on the criterion of reliability and allows to obtain the cable composition for a subsequent order from the manufacturer. The algorithm of selection combined return conductor that contains two stages: pre-selection based on the reference data, the choice of the real parameters from the manufacturer.
Keywords: OPGW, reverse wire, combined reverse wire, electrothermal degradation, fiber-optic transmission lines railway transport, traction network, the choice of combined shield wire
Nowadays the rolling stock is equipped with electric drive of high power. Frequency turning regulation, motor protection from overheating and limitation of starting currents are made with the help of semiconductor elements. For reliability improvement of starting and regulating facilities it is reasonable to use low component count. Running through regulating facilities current decrease simplifies electric circuit configuration. The authors propose to use thermal resistors as main elements. In the article the authors examine construct specifications of polycrystal temperature dependent semiconducting resistances of coaxial type and their advantages. There are some theoretical propositions which describe the work of thermal resistors and also some algorithms for synthesis of coaxial type starting devices. The authors made mathematical modeling for starting devices of different types based on thermal resistors. In the article there are some graphical dependences describing starting process.
Keywords: high power thermal resistors, thermal resistors of coaxial type, current density, specific generations of heat, criteria of similarity, starting device, starting current, synthesis of starting devices
Analysis of ways to enhance the intensity of the heat radiator sections of the cooling system of diesel locomotive. The technique and results of experimental studies of heat exchange in the condensation of steam inside the radiator sections of the locomotive.
Keywords: radiator section, the locomotive, the coefficient of heat transfer, heat transfer coefficient, condensation, experimental study
In the article the questions of technical and economical justification of the physical and mechanical compressed aitr drying are looked over. The detailed calculation for price index and economic profit for wagon exploitation depot are given.
Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production
The authors examine an alternative method of traction station load balance which needn’t capital investments for technical extension. The authors solve the task of loading partial balancing and suggest exploited transformer construction changing.
Keywords: Balancing transformer, the coefficient reverse sequence, regulation voltage under load.
Is presented the solution of important sectoral issues to improve traffic safety of rolling stock by reducing lateral wear of wheels and rails heads when changes trucks in curves parts of the route by increasing reliability and durability of the pivot site.
To resolve this task, the paper proposed to the original design decision metered supply of lubricant to the friction surfaces of the parts with wear and tear their contact surfaces. According to the proposed resolution on friction surfaces pivot site are hollow, filled with solid composite lubricant, which in process of deterioration will portions get in contact area.
Theoretical foundations and the equation of adaptive management is present.
Keywords: center plate, adaptive regulator, operating parameters, lubricating layer, wear