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Hydraulic unit to wood crusher
Trška, Andrej ; Mazal, Pavel (referee) ; Dvořáček, Jiří (advisor)
This bachelors´s thesis is dealing with construction of wood log splitter machines. Main goal of first part is to take a look and summarize the log splitter machines, theirs separation, parameters and application. The second part is dedicated to construction of homemade log splitter.
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Transmission of Linear Pneumatic Cylinder
Bedeč, Csaba ; Mazal, Pavel (referee) ; Nevrlý, Josef (advisor)
The main subject of this bachelor's thesis is analysis and design of a mechanism for converting linear motion to rotary swinging motion used as door drive in the buses. The first part contains analysis and application of the applicable types of mechanisms. The work contains analysis and design of a cam-type mechanism in the second part. The analysis of the designed variants and selection of optimal parameters of the proposed mechanism is the last part.
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Evaluation of Cyclic Damage in Aluminum and Magnesium Alloys Using Acoustic Emission Technique
Vlašic, František ; Samek,, Jiří (referee) ; Fiala, Jaroslav (referee) ; Pazdera, Luboš (referee) ; Mazal, Pavel (advisor)
The thesis deals with the application of nondestructive testing methods (acoustic emission, electron microscopy, X-ray diffraction topography) to description and identification of stages in the fatigue process in aluminium alloys. The main contribution of this dissertation thesis consists of the approach and evaluation methodology of cyclic damage in the materials. It dealt especially with the verification of measured data by using data obtained using other nondestructive methods. The experimental results show that the field of nondestructive testing materials can fundamentally uncover the process of fatigue damage and improve current knowledge in this area. Combination of used methods has become a powerful tool for the identification and monitoring of the whole fatigue degradation process of materials.
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Localization and identification of damage type of pneumatic drives
Richter, Vladislav ; Dočkal, Aleš (referee) ; Mazal, Pavel (advisor)
Pneumatic drives are an integral part of many machinery, with high demands on their reliability. Unfortunately, they sometimes fail, either due to improper production or assembly at the factory or by gradual degradation of moving parts and sealing elements during operation. Current diagnostic methods do not allow localization or identification of the type of damage and do not allow the operator to make a qualified decision. This work deals with the use of acoustic emission for these purposes. On PB type cylinders manufactured by Poličské strojírny a.s., a methodology is introduced which leads to the direct identification or at least localization of selected defects. By implementing this methodology in the final inspection of the production plant, the percentage of exposed pieces of waste will be increased, thus preventing accidents of these faulty pieces during operation.
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Design of clamping device for machining of manifold part
Foltýn, Jan ; Mazal, Pavel (referee) ; Svoboda, Petr (advisor)
This thesis deals with clamping fixtures. It aims to design an effective clamping solution for machining parts on a milling machine. The clamping solution was designed and then verified by a series of calculations. The main goal and partial objectives were fulfilled. The output is the design of fixture, which can clamp given part. Subsequently, based on the calculations it was decided to use four of these fixtures on one machining table. When calculating the appropriate variation of the fixture layout, an estimate of the time required for the operations performed by the machine operator was made. The thesis offers an overview of the materials used in the automotive industry. Furthermore, the study of clamps and clamping systems. It also touches the problem of optimizing manufacturing process and demand for ways to speed up the manufacturing process.
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Draft production line for light transmitting LiCrete blocks
Caletka, Tomáš ; Čížek, Petr (referee) ; Mazal, Pavel (advisor)
The aim of this thesis is to design a production line for manufacturing of light transmitting bricks LiCrete. This brick is a special interior design component which is made of concrete and light transmitting parts. It’s manufactured by casting into the dismountable molds. The research part explains manufacturing technology and possibilities to build production line. The concept solution part is about two concepts of production line and about a few ways how to integrate vibration machine into the line. Main part of the thesis describes mechanical design solution with focus on manipulators and vibration part. Last part of the thesis is about design of automation integration into the production line.
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Mechanical design of rotary satellite antenna polarization system
Vítek, Petr ; Mazal, Pavel (referee) ; Paloušek, David (advisor)
The aim of this bachelor thesis is mechanical design of rotary satellite antenna polarization system. It is a part of a mobile satellite antenna positioned on the roof rack of a passenger car. Device must be designed to achieve precise positioning and smooth running. It must also resist moisture and temperature fluctuations. For this application, there has been selected and developed solution with toothed belt. The thesis includes a selection algorithm of drive, belt and bearings. The achieved polarization angle is 180 °. The results of this paper can be used to produce a functional mobile satellite antenna polarization.
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Influence of dynamic loading on the contact fatigue characteristics of bearing material
Hložek, Jiří ; Hutař, Pavel (referee) ; Mazal, Pavel (advisor)
This thesis deals with the study of sudden step changes observed in model testing of standard bearing steel 100Cr6. Methodology of experiments with step change of load is proposed and applied in measurements. Three complete series of experiments were conducted, and rating life was determined for each loading trend. Based on the experiments carried out, it was found that the selected steel is able to withstand the sudden step of load changes, despite the fact that it is not material of choise for this type of load. Part of this work was to verify functionality of the innovated test stations AXMAT with modern diagnostics and a new control system, and also of the hydraulic variant of AXMAT, which allows to remotely derive dynamic loading of the test sample.
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Initiation and development of cyclic damage in steel for the energy industry
Horník, Vít ; Mazal, Pavel (referee) ; Věchet, Stanislav (advisor)
The main content of this master's thesis is a determination of the fatigue properties by using non-destructive testing methods – the acoustic emission technique and the X-ray diffraction. The reactor steel, that is named GOST 15Ch2NMFA, is used as a model material and is used to manufacture VVER-1000 reactor pressure vessels. The supplied material was made of two different steel melting, designated as H and S. For the basic measurement of the fatigue properties the stress-cycle asymmetry R = -1 was used. Some of the samples were used for approximate determination of the fatigue strength stress-cycle asymmetry R = 0. During the loading process the resonance frequency of the loading machine and acoustic emission signals were recorded. The changes in microstructure were estimated from the record of acoustic emissions during the whole fatigue life. The change of the microstructure was experimentally observed by X-ray diffraction analysis. The mechanism of the fatigue can be described by the observation of the microstructural processes as well as the relevant bifurcation with sufficient sensitivity. The results of the used methods indicate a decay and re-growth of mosaic blocks during the whole loading process. Therefore, it is important to find a correlation of these two non-destructive methods, or to use other non-destructive testing methods in the future.
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