Journal of Transsib Railway Studies V.2(38), 2019

Wearing parts of the cylinder-piston group and crank mechanism is one of the main reasons for putting a diesel engine into repair. Timely detection of the occurrence of intense wear allows you to prevent negative consequences, make timely repairs, eliminate the likelihood of unplanned exit of the locomotive from service. As a result of the study of the intensity of accumulation of wear products in engine oil, a mathematical model has been developed, which is implemented with the use of an artificial neural network apparatus. Its use allows to carry out an operational assessment of the technical condition of diesel engine parts in an in dividing way and to improve the technological process of repairing diesel engines of the D49 type

A modern solution to the problem of improving the efficiency of the traction rolling stock maintenance and repair processes based on the use of new information technologies is the transition to a locomotives predictive repair promising system. The key element of the predictive repair system in the issue of operational assessment and management of the locomotives technical condition are onboard microprocessor control systems with built-in diagnostic, monitoring and monitoring subsystems. The onboard microprocessor control systems have the ability to carry out continuous or discrete measurement, registration, transmission and accumulation the values of large package analog and discrete locomotive equipment parameters. The functionality of the onboard microprocessor control systems based on information technologies makes them an exceptionally effective means of efficiently organizing maintenance and repair impacts on the locomotive park in order to ensure specified operational reliability and performance indicators.

Based on the analysis of the empty rolling stock on the Krasnoyarsk and East Siberian Railways, the technical parameters that have a significant impact on the unloading of the wheel of the first wheel pair in the course of movement are determined. The design features of wagons influencing the safety coefficient of train traffic are considered. Statistical processing of these gatherings, according to the materials of official investigations, revealed a number of interesting features. One of them is non-normalized total gaps in the sliders along the diagonals of the wagons. This fact in the movement of empty car causes misalignment of the body, which in turn leads to a redistribution of the loads acting on the spring kits on the sides of carts and wagons. The influence of elastic suspension parameters (height, spring break) on the redistribution of loads acting on the sides of the trolley is considered. The misalignment of the body of empty wagons, especially wagons with a sufficiently small mass of unsprung parts and a high center of gravity, leads to a significant reduction in the safety factor. The calculation of the transverse guiding forces acting at the point of contact of the wheel and rail, as well as their effect on the unloading of the wheel. It is revealed that the body skew leads to a significant increase in lateral force, which affects the stability of the empty rolling stock.

The purpose of the work is to assess the energy efficiency of recuperative braking of a passenger DC electric locomotive when a train is moving at an unsteady and steady speed, to determine the degree of influence of the speed of movement and electric heating of passenger cars on the return of electricity during recuperative braking of an electric locomotive, to develop recommendations for improving the energy efficiency of passenger DC electric locomotives. The following methods were used: comparative analysis, methods of traction calculations, linear regression analysis, energy balance method. The equations of the energy balance of the movement of a passenger train and its components are considered in the mode of regenerative braking, allowing to identify the main factors affecting the return of electricity. The dependences of the return of electricity during regenerative braking, allowing to evaluate the influence of the train running mode and electric heating of passenger cars on the return of electricity during regenerative braking of an electric locomotive, are obtained. Developed recommendations to reduce the energy consumption of passenger trains. The conditions under which it is possible to increase the return of electricity during regenerative braking of passenger electric locomotives are determined. The developed proposals will allow increasing the energy efficiency of passenger DC electric locomotives.

The paper is vibration investigation in a case of guiding of railroad vehicle in curves with low radius. Experimental methods. Examine results of the investigation of vibrations on box bearing of railroad locomotive in a case of mountain trucking with large count of curves with low radius. It is show, that in a case of locomotive guiding in a low radius curves a pseudo-random vibration arise. The level of the pseudo-random vibration in a low radius curves exceeds the vibration in the rail joint, but vibration in the guiding is semi continuous. In a case of locomotive working, also the harmonics of gearing is shown. The spectral density of vibration accelerations is presented in a three-dimensional form, coded in color on a two-dimensional time-frequency diagram for estimating the vibration spectra and their probable sources.

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 presents the results of the study of the influence of deviations of certain design parameters of bogie from established normative values on a relative offset from the crests of wheel pair in mezhdurelsovom space of railway transport. Such deviations occur in the process of the gradual wear of moving parts in real-world conditions of rolling stock and lead to a change of kinematic parameters of bogie. An analysis of dependence of lateral displacement relative to the wheelset of railway track from the difference between the diameters of the tapered surfaces of wheelset, skating from lack of alignment of wheelsets and difference coefficients rigidity of springs of bogie. The proposed mathematical model allows to not only diagnose technical condition of wagon bogies during their movements on the straight section of railway track, but also forecast the rolling stock maintenance dates the whole on the basis of position measurements of wheel pairs regarding railway track.

A mathematical model of thermal processes (dynamic) contact current collector with contact suspension (in motion), which allows to estimate the temperature distribution of heating the current collector during movement. The experimental evaluation of the proposed cooling device performance is given. The thermal model of the current collector in motion mode has been verified.

With the advent of new series of locomotives, the development of heavy freight trains, the increasing speeds of passenger trains, the introduction of innovative technical means and technologies, the degree of influence of various indicators on energy consumption is redistributed. The aim of the article is to develop a methodology for monitoring the efficiency of locomotives when changing the set of operational factors. This will make it possible to more accurately determine the estimated change in specific energy consumption, which in turn will increase the objectivity of the assessment of the causes of changes in the energy intensity of transport and will help to reduce energy losses.

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 necessity of searching for new methods to improve the dynamic rationalized properties of the traction drive, which does not create contradictions between the conclusions based on the results of numerical parametric analysis and the results of the analysis of nonparametric factors, is established. A modified base point method is proposed that takes into account the possible presence of areas of conservatism of a rational parameter and provides for a procedure for checking for conservatism. The search results using this method for a rational version of a traction drive with a support-frame suspension of an electric motor and a gear reducer coincide with the empirical choice of different manufacturers of locomotives.

In article the design of an automatic pneumatic brake of the car with the braking accelerator is offered. Use of the developed accelerator of braking of an automatic pneumatic brake by freight cars allows to reduce a brake way of the train and to reduce longitudinally dynamic forces in the train when braking.

The development of railway transport is currently impossible to imagine without the use of mathematical models and algorithms. Consider the increase in speeds, reduction of travel time, while minimizing costs, is possible only with the qualitative and full use of the mathematical apparatus. The use of information technologies makes it possible to take an effective decision in the development of a project for the reconstruction of a railway line. The current state of the theory of railway transport is characterized by the presence of a developed system of mathematical models and algorithms for analyzing various features of railways. This opens up possibilities for building an approach to the problems of searching and optimizing design solutions on a mathematical basis, with the reduction to a minimum of costly and time-consuming physical modeling procedures. One of the main tasks that are set for the railway transport in the near future is to increase the speed of trains on existing railway lines with the use of computer technology (computer-aided design). The article deals with the problems of technical reconstruction of the railway plan to increase the speed of train movement. The urgency of the use of computer mathematical methods for the development of an optimal plan for increasing the speed of trains. A pair of mutually dual problems of optimal reconstruction of railway curves to increase the speed of trains with minimal capital investment is considered. As methods for solving the problems posed, the following methods were proposed: the method of steepest descent, a modified method of dynamic programming (the Cattell method), the method of indefinite Lagrange multipliers. The expediency of using each method to solve the problem is indicated. The considered methods allow to implement a number of computer-aided design procedures for the reconstruction of the railway plan.

The article discusses issues of simulation modeling of technological processes of repair of rolling stock components. A model of the technological process of repairing a trolley (mod. 18-100) of a gondola car in an ARENA environment is given.

The article presents the relevance of the use of sources of low-potential, secondary thermal energy, as well as a method for calculating the dependence of the propylene glycol temperature on the depth of a single-well coaxial collector, with constant values of the parameters of the geothermal well. The proposed methodology of the geothermal reservoir, allows to determine the optimal depth of the well, in which the increase in the temperature of propylene glycol in practical terms does not change, respectively, further drilling becomes economically inefficient.

The authors consider the question of the limits of applicability of the capacitor method for measuring the real part of the dielectric constant of printed circuit boards and telecommunications cabled rail transport using the example of FR-4 fiberglass laminate and the cable PK-75-4-12 in the frequency range from 10 Hz to 100 MHz. The measurements were carried out at a constant temperature and humidity of a known material. Comparison of the obtained values with the passport data on the material is carried out; a measurement procedure is developed with overlapping frequency ranges by changing the values of the measuring resistors from larger to smaller with increasing frequency of the input signal. It is shown that in the high-frequency region, the measurement accuracy is directly affected by the parasitic inductance of the capacitor sample under study, as well as the active resistance of the leads and plates and its increase due to the skin effect. The article also discusses the ways of accounting and calculating the parasitic elements of a capacitor. One of these ways is to study the characteristics of the elements of the sample at the first proper serial resonance of the capacitor under study.