National Repository of Grey Literature 56 records found  beginprevious21 - 30nextend  jump to record: Search took 0.01 seconds. 
Off-board systems for top-of-rail lubrication
Málek, Jan ; Kvarda, Daniel (referee) ; Galas, Radovan (advisor)
This bachelor’s thesis is focused on rail off-board lubrication system. The main part of this thesis is explaining of function and design few certain lubrication systems. In this thesis are explained aspects of wheel-rail contact, such as types and parts of rail, adhesion, slip, creep–traction diagram. Another part of this thesis is description of few certain lubrication system for top of rail and gauge face application. In this thesis are explained product of major companies of friction management industries such as SKF-Lincoln, Whitmore, Loram. Additional part of this thesis speaks about usage and development of this devices in Czech Republic. Output of this thesis is conclusion about advantages and disadvantages these certain devices.
Design of a test condition for determining the wear at the contact of a railway wheel and rail
Rec, Matouš ; Prokop, Aleš (referee) ; Řehák, Kamil (advisor)
This diploma thesis focuses on the issue of a wear of a railway wheel and a rail. The wear of the components depends on a number of parameters including the contact stress, the contact pressure and the contact surface dimensions. Among the factors determining these parameters belongs primarily the wheel driving gauge, the rail profile and the load of the contact area. Furthermore, the material from which the wheels and rail are made, the roughness and hardness of the functional surfaces and the residual stress in the material have a significant impact on the wear. All the parameters mentioned above are designed for the production of the railway wheels and rails and therefore they meet the standards for the production of these components. However, the existence of the changeable parameters has also a significant impact on the wear. These parameters include the presence of contaminants, or lubricants in contact, the changing driving gauge due to the wear, the slip ratio or the friction coefficient. With the wear being an inevitable process during the application it cannot be eliminated but only controlled. Applying the lubricant into the contact when passing through the arc in order to achieve an ideal coefficient or the maintenance grinding for restoring the driving gauge can serve the purpose. If properly optimized, the importance of the wear research lies in the financial savings. Being the crucial factor for optimization of the intervals between the maintenance grinding, the research is also beneficial. A high-quality wear prediction can be seen as the key field in order to increase the safety of the railway vehicles operation as well. Therefore, the wear research is made using several methods, such as the computational models, the multi-body dynamics software and the technical experiments. This thesis introduces a conceptual design of the test, enabling the wear research via experimental approach. The final device is capable of a simulation of both volume and fatigue wear during the states the railway wheel and railway undergo including riding on the straight track, passing through an arc or a wheel slip during braking.
Upgrading of Milevsko Railway Station
Křemen, Tomáš ; Kubrt, Petr (referee) ; Svoboda, Richard (advisor)
The aim of the diploma thesis is the reconstruction of Milevsko railway station. The platforms with access persons with reduced mobility are designed in this station. The rail substructure and station drainage system design was necessary to do within the reconstruction. New assembly of a switches and crossing is the part of reconstruction design as well.
Computational modelling of complex eigenfrequencies of the tram wheel during cornering
Burian, Josef ; Hadaš, Zdeněk (referee) ; Švancara, Pavel (advisor)
This Master’s thesis deals with the computational modeling of complex natural frequencies of the tram wheels during cornering. The aim of this work is to determine eigenvalues, perform analysis of the influence of different parameters on eigenvalues and perform harmonic response analysis in order to find surface velocities that can be used in future noise emission analysis.
Modernization of Brno - Přerov railway line in Vyškov area for speed 200 km/h
Hašek, Jan ; Rotschein, Petr (referee) ; Plášek, Otto (advisor)
The objective of this master´s thesis is a design of modernization of railway line no. 300 Brno – Přerov in Vyškov area and its vicinity for speed 200 km/h. The track section is located between railway station Luleč and Ivanovice na Hané. The track is designed in two variants. The first variant is proposed keeping railway line through Vyškov railway station including necessary modification of the railway station. The second variant suggests keeping track outside Vyškov and a connection with the railway station by bridging is designed.
Assessment of Geometry Parameters of Track with Under Sleeper Pads
Škovranová, Michaela ; Volejník, Miloslav (referee) ; Hruzíková, Miroslava (advisor)
The diploma thesis applies to under sleeper pads. It researches thein using and benefits in foreign railvway authorities. Further it assesses track geometrical parameters in the trial track section with under sleeper pads in track Havlíčkův Brod - Okrouhlice and in the railway station Planá nad Lužnicí. There were evaluated measurements of vertical alingnment rails by precise leveling and deviations of track geometrical parameters measured by track meusuring car in the diploma thesis.There is expressed an conclusion about the impact of under sleeper pads on track geometric data in the thesis.
The effect of climate conditions on wheel-rail contact adhesion
Nohel, Rostislav ; Horák, Zdeněk (referee) ; Omasta, Milan (advisor)
Presented master’s thesis is focused on the experimental research of influence of climate conditions on wheel-rail adhesion, where climate conditions are meant two parameters: ambient air temperature and air humidity. These parameters always affect wheel-raid contact and their values change significantly during the year. For presented experimental research was used tribometer Mini Traction Machine (MTM) in configuration „ball on disc“. For determination of influence climate conditions was first found out the influence of air humidity on adhesion at certain temperatures, which varied between (1 to 50) °C. These experiments were performed for two types of discs, where one disc was exposed to leaf extract contamination. After that was assembled influence of both parameters (air humidity and ambient air temperature) on adhesion in the form of a 3D map, where were distinctioned states, when condensation has occured and when didn‘t. Obtained results in this thesis will be used for optimalization of rail vehicle control systems.
Bludov - Hanusovice Railway Track Reconstruction (section between km 56.165 - km 59.105) Including Track Laying Technology
Hlavová, Vendula ; Korkeš, Ondřej (referee) ; Říha, Tomáš (advisor)
The bachelor thesis deals editing track geometry parameters and design appropriate track railway superstructure in a section of railway Bludov – Hanušovice. The design should be considered primarily on existing objects as culverts, railway crossing, railway stops, and bridges. Thesis includes restoration of drainage, track laying technology and efforts to incease the track speed.
Development of Long-pitch Corrugation in Curves of Small Radii
Valehrach, Jan ; Kohout,, Martin (referee) ; Lidmila,, Martin (referee) ; Plášek, Otto (advisor)
Throughout the operation, the rails are worn and deteriorate. With the increasing speed of rolling stock, along with higher track loads and especially in the vicinity of major traffic hubs with a higher frequency of trains, defects that did not occur to such an extent before or were not considered to be significant, are brought to the forefront of the concerns of track infrastructure managers. Even though these defects are not directly restrictive to traffic operation, they are, in any case, a source of noise and vibration. One of these defects on the railway track is the micro-geometry defect of the running surface of the railhead. In directional curves with radii of less than 600 m or 700 m, defects known as long-pitch corrugation occur on the inner rail. In curves with 300 m or smaller radii, these waves are so distinct that they are a significant source of noise and vibration. In particular, vibrations affect the track surroundings and the track itself, as they cause other defects in the track structure. This dissertation deals with long-pitch corrugation, focusing on the monitoring of wave generation and development over time. The verification of the possibility to track the development of slip waves over time is the basis for possible future models predicting the development of defects. Numerous measurements of geometric parameters of the track and microgeometry of the railheads, specifically slip waves, have been carried out in the framework of the problem. Using RMS and peak-to-peak methods, the rate of development of defects over time and the relationship with other track parameters were evaluated. Based on the obtained development curves, intervals for further maintenance interventions were estimated. A part of the thesis focuses on the deficiency or excess of cant concerning the development of long-pitch corrugation.
Rail wear in track curves of small radii
Schneider, Martin ; Szabó, Petr (referee) ; Plášek, Otto (advisor)
The diploma thesis deals with a rail wear in curves with a small radius (R < 500 m), in the national corridor railway, between stations Blansko and Svitavy. The diploma thesis deals with the impact of the track gradient, the horizontal layout of the track, traffic composition, and direction of travel on the size of the horizontal and vertical rail wear. Also, the influence of rail steel grade is discussed in the diploma thesis.

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