Science and Transport Progress

7-14

Authors: A. M. Beznaritnyy, V. I. Gavrilyuk, I. O. Romantsyev, V. I. Shchyeka

Purpose. It is necessary to identify the influence nature of the electric stock on the equipment of rail circuits that is used in automatic blocking devices and electrical centralization. Methodology. During the preparation phase the experimental investigations in real operating conditions of track circuits were conducted. The method of fast Fourier transform was used during the analysis of experimental data. Findings. The conducted research made it possible to evaluate the spectral composition of the traction current in a rail line under the influence of electromotive traction rolling stock with different characteristics of traction motors. Originality. As a result of research the characteristics of traction current, which is formed by modern accelerated traction rolling stock with asynchronous traction motors in rail lines were obtained. The harmful influence of traction current generated by such rolling stock on the operation of rail circuits of railway automatics was presented. Practical value. Experiments show the increase of harmful influence of return traction network on signaling and blocking devices during adoption on accelerated motion section. The obtained results can be used as a basis for development of rail circuits protection from interference, increase of electromagnetic compatibility of traction network with the adjacent lines and the development of technical diagnostics systems.

24-33

Authors: M. I. Muzykin, G. I. Nesterenko

Purpose. The article aims to analyze the stabilization process of train movement after interruption and loss of the working capacity. Methodology. To examine the process of train movement on the route (double-track line with sorting station) in extreme conditions during the maintenance windows for capital repair of the track. During the investigation of this process time calculations of a normal motion restoration after the maintenance windows were carried out. In this process there are no organizational interventions aimed to change various coefficients. It is presented in the research in its pure form, in order to show how the system comes to equilibrium. Findings. It was found out that the major losses of working capacityduring the maintenance windows occur as a result of perturbations caused by interruptions, not the interruptions in themselves. The actual idle time in the study is about 300 train-hours. Directly because of the maintenance window it is 129 train-hours. Losses were equal to more than half of total idle time of trains caused by the maintenance windows. Originality. The authors proved the possible reduction of working capacity losses on railway direction as a result of a deliberate action on this process. Practical value. Implementation of these actions will reduce the losses of the working capacity.

42-50

Authors: YU. S. Bondarenko

Purpose. Application of physical modeling as a tool for research of any events or systems is becoming more widespread, including the field of railway transport. At the same time the adequacy of results that can be obtained, depends largely on the similarity degree of the physical model to real system. From the standpoint of the traction asynchronous electric drive (TAED) research together with the traction power supply system research, the similarity can not be determined by the direct proportion of the parameters, because the processes nature accompanying the operation of these systems is non-linear. These features should be taken into account in the experimental setup, the basis for constructing of which is establishing of the system similarity that defines the purpose of this paper. Methodology. At the heart of the experimental setup creation laid reproduction of processes of energy transformation in the system of the DC traction power supply. Determination of the similarity degree of the proposed facility to the real system was carried out using the basic theorems of the similarity theory, their additional provisions on the complexity and nonlinear systems, as well as elements of mathematical analysis. Findings. According to the results of work: 1) The block diagram, the energy conversion mechanism of which is similar to the real system was received. This scheme is the basis of experimental setup, built in the future for the study of electromagnetic compatibility of TAED in the structure of DC traction electric power supply system. 2) Similarity of obtained structural scheme with the real system with the mechanism definition of calculating the scaling relations was established. Originality. In the process of establishing the similarity a simplified method for determining the scaling relations for nonlinear systems was suggested. They are identical in their structure components, but have different capacities. Practical value. Experimental research of electromagnetic compatibility of TAED in the structure of traction power DC system using the elements of similarity theory will provide more adequate results and, as a consequence, create preconditions for further improvement process of the aggregate related systems functioning of electrified railways.

65-74

Authors: I. O. Vakulenko, O. N. Perkov, M. Knapinski, D. M. Bolotova

Purpose. Damageability estimation of carbon steel in the conditions of cyclic loading. Methodology. The steel fragments of railway wheel rim and rail head served as material for research with chemical composition 0.65 % С, 0.67 % Mn, 0.3 % Si, 0.027 % P, 0.028 % S и 0.7 % C, 0.82 % Mn, 0.56 % Si, 0.025 % P, 0.029 % S accordingly. The microstructure of tested steels corresponded to the state of metal after a hot plastic deformation. The fatigue research was conducted in the conditions of symmetric bend using the proof-of-concept machine of type «Saturn-10». Full Wohler diagrams and the lines corresponding to forming of sub-and micro cracks were constructed. The distribution analysis of internal stresses in the metal under cyclic loading was carried out using the microhardness tester of PMT-3 type.Findings. On the basis of fatigue curves for high-carbon steels analysis the positions of borders dividing the areas of convertible and irreversible damages were determined. The article shows that with the growth of carbon concentration in the steel at invariability of the structural state an increase of fatigue limit is observed. At the same time the acceleration of processes, which determine transition terms from the stage of forming of submicrocracks to the microcracks occurs. The research of microhardness distribution in the metal after destruction confirmed the nature of carbon amount influence on the carbon steel characteristics. Originality. Regardless on the stages of breakdown site forming the carbon steels behavior at a fatigue is determined by the ration between the processes of strengthening and softening. At a cyclic loading the heterogeneity of internal stresses distribution decreases with the increase of distance from the destruction surface. Analysis of metal internal restructuring processes at fatigue loading made it possible to determine that at the stages prior to incubation period in the metal microvolumes the cells are already exist with inhomogeneous position of crystalline structure defects and, primarily, dislocations. Practical value. Increase of carbon content from 0.65 to 0.7%, in the conditions of cyclic loading of steel with the structure of lamellar pearlite is accompanied by the fatigue durability increase approximately on 40%. The increase of carbon content in steel accelerates transition from the stage of forming the convertible damages of internal structure to irreversible ones that is confirmed by the increase of angular coefficient of French curves.

84-91

Authors: A. YE. Kapustyan, A. V. Ovchinnikov, I. A. Vakulenko

Purpose. Limited application of details from powder titanium alloys is connected with the difficulties in obtaining of long-length blanks, details of complex shape and large size. We can solve these problems by applying the welding production technology. For this it is necessary to conduct a research of the structure and mechanical properties of welded joints of sintered titanium alloys produced by flash welding. Methodology. Titanium industrial powders, type PT5-1 were used as original substance. Forming of blanks, whose chemical composition corresponded to BT1-0 alloy, was carried out using the powder metallurgy method. Compounds were obtained by flash welding without preheating. Microstructural investigations and mechanical tests were carried out. To compare the results investigations of BT1-0 cast alloy were conducted. Findings. Samples of welded joints of sintered titanium blanks from VT1-0 alloy using the flash butt welding method were obtained. During welding the microstructure of basic metal consisting of grains of an a-phase, with sizes 40...70 mkm, is transformed for the seam weld and HAZ into the lamellar structure of an a-phase. The remaining pores in seam weld were practically absent; in the HAZ their size was up to 2 mkm, with 30 mkm in the basic metal. Attainable level of mechanical properties of the welded joint in sintered titanium alloys is comparable to the basic metal. Originality. Structure qualitative changes and attainable property complex of compounds of sintered titanium alloys, formed as a result of flash butt welding were found out. Practical value. The principal possibility of high-quality compounds obtaining of sintered titanium alloys by flash welding is shown. This gives a basis for wider application of sintered titanium alloys due to long-length blanks production that are correspond to deformable strand semi finished product.

100-108

Authors: A. V. Gaydamaka

Purpose. Lack of kinematics models and imperfection of the known dynamics models of the roller bearings of railway rolling stock axle-boxes do not allow designing the optimal structure of bearing cages, providing the required service life and reliability of bearing units of wheel sets for cars and locomotives. The studies of kinematics and dynamics of roller bearings of axle boxes for cars and locomotives and modeling of their parts interaction to create the analytical method of bearing cages calculation are necessary. Methodology. This purpose has been achieved due to the modeling of kinematics of the ideal (without gaps) and real (taking account the gaps, manufacturing and installation errors) bearings, substantiation of the transfer mechanism of motion from the rollers to bearing cage, modeling the dynamics of rolling, research of interaction forces of the rollers with bearing cage. Findings. It is established that the kinematics of ideal bearing is determined by the contact deformations of the rollers and rings, when the kinematics of real bearing depends mainly on the side gaps in the windows of the bearing cage. On the basis of studies of the real bearing kinematics the dynamics models of the rollers and bearing cage interaction were constructed. The conducted studies of kinematics and dynamics of rolling bearings have changed our view of them as of the planetary mechanism, explained the reason of bearing cage loading, and confirmed the possibility of destruction during operation. Originality. It was first proposed a mechanism for motion transfer from the rollers to the bearing cage of roller bearings, consisting in that the side gap in the bearing cage window is reduced gradually multiple of the number of rollers of radial loading area according to the bearing cage motion. The models of roller bearing dynamics, which allow calculating the interaction forces of parts for all modes of operation, were improved. Practical value. Use of the offered models of kinematics and dynamics of the roller bearings will develop analytical calculation method of the bearing cage for the choice of its optimal design according to criterion of maximum service life and reliability of the bearing unit of wheel sets of the railway rolling stock.

117-123

Authors: G. Vaiciunas, S. V. Мyaмlin, A. A. Bosov, V. YA. Panasenko, I. V. Кlimenko, YE. F. Fedorov

Purpose. One should clarify the issues concerning the wear reduction of details of freight car side bearers, costs reduction for the worn details reconstruction, improvement the dynamic characteristics of railway vehicles and the increase of their movement safety. Methodology. Wear-resistant elements of the side bearers are made in the form of removable metal-ceramic plates, entrenched on friction planes. Findings. During operation due to pollution, wear of friction surfaces and other causes the power characteristics of side bearer may significantly vary, which adversely affects the dynamic qualities of bogies, and as a result the train traffic safety. Therefore, the solution proposed by the authors concerning the operation improvement of elastic frictional side bearers by means of their modernization is an urgent one. Originality. The design of the bogie side bearer of freight car was improved. Friction wedge was set on the spring; its inclined surface interacts with a support inclined platform of a plate through the plate with the durable elements in the form of metal-ceramic inserts. Practical value. The use of wear-resistant elements in the form of interchangeable metal-ceramic inserts will reduce the wear of connection joints of bogie and a freight car frame, improve its dynamic qualities. It will also decrease the costs for restoration of worn side bearers by friction.

136-145

Authors: S. V. Myamlin, O. O. Ten, L. O. Neduzha

Purpose. With the advent of new designs of freright cars the task of designing the more modern bogies, assessment of their dynamic properties depending on the type and structure of pecularities, accounting the axle loadings, providing the dynamic and running characteristics, meeting the conditions of impact on the track, stability, and frame forces intensity etc. becomes especially important. In order to launch the new production into manufacture and to assess the dynamic properties using different designs of bogies the running testes were conducted. They allowed one to compare the dynamic performance of the new bogie with the existing models. Methodology. The study was conducted using the method of numerical integration and mathematical modeling of dynamic loading of freight cars using the software package «Dynamics of Rail Vehicles» («DYNRAIL»). Findings. The results of studies of dynamic characteristics of open cars with new and worn wheels of bogie models 18-9771, 18-9770 and 18-578 in graphical and tabular form are presented. All figures are within the normative values and do not exceed the maximum admissible ones. Originality. When designing the bogie for loading 23.5 t/axle almost all available technical solutions to improve the characteristics of the freight car bogies (elastic bearers, cassette bearing in axle boxes, axle boxe adapter of original design, bilinear central spring suspension, etc.) were used. Practical value. As a result of the engineering works on projecting and manufacturing of the improved designs of freight car bogies a new design was received. It is highly competitive with the dynamic qualities of the best ones. Made choice of rational values of elastic-dissipative parameters of the bogie allows one to create standard series of running gears for freight cars for promising operating conditions.The results are of practical importance. They have found reflection in the number of author’spublications in special and semi-populareditions.

160-173

Authors: N. V. Marchenko

Purpose. Statistical analysis of inventive activity in Ukraine shows that the largest number of applications is submitted by employees of universities and research institutions – almost 60% of all inventions. Practice of inventions execution proves that for researchers, especially for students, the most difficult part of the application and author documents is the claim. The purpose of research is a synthesis and supplying the general principles of quality drafting the patent claim, providing further legal protection of the patent. Methodology. Monitoring and analysis of the world documentary informational flow through the civil protection mechanism of the assignee rights on the basis of the patent claim allows us to compare the world systems of formulas development and summarize some key moments concerning the point in question. The example analysis of the correct patent claim drafting and its interpretation in court cases on intellectual property was made. Findings. The specific properties of the patent claim were described. They are conciseness, latitude, completeness and certainty, compliance with unity requirements and novelty of the invention. On the basis of the research it is established that there is a great difference between Ukrainian and American patent claims. A number of common mistakes and shortcomings during the claim drafting were identified. The need to restore the various forms of the invention training in universities of Ukraine was emphasized, since on this basis one should train a number of specialists who are able to carry out the commercialization of intellectual property results into productive findings. Originality. A number of issues and techniques was investigated and summarized. They can be applied by the courts in interpreting of the patent claim in the processing of intellectual property cases. Especially it concerns determining the correct drafting of the patent claim. Practical value. This work may be used during the drafting of patent claim. It will give the possibility for assignees and inventors to avoid the errors when drafting the claim. The results of the conducted research can be applied in the processes of civil protection in cases of intellectual property. The material presented in this article can also be used at lectures on the intellectual property disciplines in the universities.