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Construction of gears with plastic teeth
Selzer, Tomáš ; Vrbka, Martin (referee) ; Křupka, Jiří (advisor)
The thesis discusses the matter of construction of gear trains using plastic parts in both lubricated and non-lubricated environment, trying to give an overview of an up-to-date information in the process. Nowadays, thanks to several years of development, polymer-based gear systems can be used in many cases as a replacement for metal-based ones. The undeniable advantage of such replacement is mostly the lower production cost and its lower weight, which, together with favorable friction properties of polymer materials, makes a number of technological applications much more effective. The first part is dedicated to listing and defining the typical characteristics of polymer materials, which are essential in the process of designing the gear. The next part focuses on evaluation of the available types of solutions for plastic gear trains construction. The last topic is centered around possible defects and the wear as well as the operation conditions and a real-life application of such plastic gear system. The most notable findings are summed up and commented on in the form a discussion. Thanks to the chosen topic, the bachelor’s thesis adds to a closer understanding of the construction and operation of the plastic gear systems.
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Conceptual design of a polymeric gear tester in vacuum
Ptáček, Matyáš ; Šperka, Petr (referee) ; Černohlávek, Mikuláš (advisor)
The bachelor thesis deals with the conceptual design of a polymeric gear tester in vacuum. Using a test device, it is possible to test the coefficient of friction in gears. At the beginning of the work is described the issue of operating conditions of satellites in low orbit together with the effects that affect them. Subsequently, suitable polymeric materials are selected, and current publicly available test rigs are described. Based on the research, two conceptual designs are made, one of them is selected and described in detail at the end of the work.
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Mechanical and Chemical Surface Endurance of polymers materials, testing and posibilities fro improvements
Vaníček, Štěpán ; Seidlová, Michaela (referee) ; Petránek, Vít (advisor)
Mechanical and chemical resistant multilayer polymeric floors are the most important characteristics of classification in the evaluation of surface and texture. Mentioned as organic binders which are used for the realization of the matrix. Further discussion on how to get fillers forming the supporting folder. Created a summary of the key test of mechanical and chemical characteristics according to current standards. The theoretical part is concluded with a reflection on the possibilities of improving the surface resistance of synthetic floors. The practical part was focused on testing the strength, resistance to impact and adhesion to the base layer. Finally, the overall evaluation of the test results in accordance with the theoretical part.
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Creation of a web application to select polymer materials based on mechanical properties for 3D printing
Kaziměrčíková, Lada ; Šafl, Pavel (referee) ; Binar, Tomáš (advisor)
This diploma thesis deals with 3D printing with a focus on the FDM method. Main objective of the thesis is to develop a web application which would assist in the selection of suitable polymer materials for FDM print, based on the required mechanical properties. The web application was created in Python with the usage of Flask framework and MySQL database. In order to develop this application, it was necessary to create an overview of material properties, mainly mechanical parameters and degradation mechanisms. Subsequently, testing in a climatic chamber was done, and also hardness and tensile tests for degraded samples. The collected data serves as the base of the understanding how given mechanical parameters may affect selection of the polymer material. The thesis then offers a practical instrument to help choose right material for FDM printing projects.
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Hodnocení kvality pomocí nedestruktivních technologií
Šarocký, Robert
This diploma thesis is focused on evaluating quality of materials which are manufactured by additive method of production. The thesis describes methods of additive production and their materials. Furthermore, the thesis deals with the methodology of investigation of mechanical properties of products of additive production. The following part of the thesis describes production of samples from two different types of material. Subsequently, these samples were tested by acoustic emission in the impact bending test and the tensile strength test.
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Využití polymerních materiálů v konstrukci dopravní techniky
HADRBOLEC, Ladislav
This bachelor thesis deals with the use of polymeric materials in the construction of transport and handling equipment. Specifically, it presents information about the history of polymeric materials, production methods and their properties. The main part of the work is interested in selected polymeric materials in specific applica-tions of transport technology, where the economic factors are subsequently ad-dressed, considering the ecological aspects of polymeric materials. The conclusion of the work presents the possibilities of using 3D printing of polymeric materials for prototype production of parts used in transport and handling technology.
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Conceptual design of a polymeric gear tester in vacuum
Ptáček, Matyáš ; Šperka, Petr (referee) ; Černohlávek, Mikuláš (advisor)
The bachelor thesis deals with the conceptual design of a polymeric gear tester in vacuum. Using a test device, it is possible to test the coefficient of friction in gears. At the beginning of the work is described the issue of operating conditions of satellites in low orbit together with the effects that affect them. Subsequently, suitable polymeric materials are selected, and current publicly available test rigs are described. Based on the research, two conceptual designs are made, one of them is selected and described in detail at the end of the work.
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Application of renewable and recyclable raw materials for preparation of new polymers
Horák, Pavel ; Beneš, Hynek (advisor) ; Cajthaml, Tomáš (referee)
This thesis deals with optimalization of flexible polyurethane foam recycling with using of natural polyols based on rape seed oil and fish oil and it explores applications of depolymerized polyol product by formulations of new polyurethane materials. The experiments of depolymerisation showed that both tested natural oil (rape seed oil and fish oil) can be used as effective reagents for polyurethane recycling. Reaction conditions of depolymerisation were optimised with model flexible polyurethane foam and applied on waste foam from real conditions. Gain of depolymerisation is one-faze low viscosity (to 1500 mPa.s) liquid polyol products with content of hydroxyl groups ca 3 mmol/g. These polyols can be used for polymerisation of new materials. First application of recycled polyols was formulation of polyurethane foam systems. Through optimising of formula was prepared low-density semirigid foam containing 100 percentage of recycled polyol. Properties of these foams correspond to commercial foams. To prepare of homogenous cast polyurethane system based on recycled polyols it was necessary to add proper solvent, therefor extent of application has been lowered. On that account the systems were tested for study of polyaddition reaction and for following properties of the material. In these tests, the reactivity...
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Application of renewable and recyclable raw materials for preparation of new polymers
Horák, Pavel
This thesis deals with optimalization of flexible polyurethane foam recycling with using of natural polyols based on rape seed oil and fish oil and it explores applications of depolymerized polyol product by formulations of new polyurethane materials. The experiments of depolymerisation showed that both tested natural oil (rape seed oil and fish oil) can be used as effective reagents for polyurethane recycling. Reaction conditions of depolymerisation were optimised with model flexible polyurethane foam and applied on waste foam from real conditions. Gain of depolymerisation is one-faze low viscosity (to 1500 mPa.s) liquid polyol products with content of hydroxyl groups ca 3 mmol/g. These polyols can be used for polymerisation of new materials. First application of recycled polyols was formulation of polyurethane foam systems. Through optimising of formula was prepared low-density semirigid foam containing 100 percentage of recycled polyol. Properties of these foams correspond to commercial foams. To prepare of homogenous cast polyurethane system based on recycled polyols it was necessary to add proper solvent, therefor extent of application has been lowered. On that account the systems were tested for study of polyaddition reaction and for following properties of the material. In these tests, the reactivity...
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Construction of gears with plastic teeth
Selzer, Tomáš ; Vrbka, Martin (referee) ; Křupka, Jiří (advisor)
The thesis discusses the matter of construction of gear trains using plastic parts in both lubricated and non-lubricated environment, trying to give an overview of an up-to-date information in the process. Nowadays, thanks to several years of development, polymer-based gear systems can be used in many cases as a replacement for metal-based ones. The undeniable advantage of such replacement is mostly the lower production cost and its lower weight, which, together with favorable friction properties of polymer materials, makes a number of technological applications much more effective. The first part is dedicated to listing and defining the typical characteristics of polymer materials, which are essential in the process of designing the gear. The next part focuses on evaluation of the available types of solutions for plastic gear trains construction. The last topic is centered around possible defects and the wear as well as the operation conditions and a real-life application of such plastic gear system. The most notable findings are summed up and commented on in the form a discussion. Thanks to the chosen topic, the bachelor’s thesis adds to a closer understanding of the construction and operation of the plastic gear systems.
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