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Design of manufacturing technology for door elastomer grommet
Kavan, David ; Stehlík, Ing. Jaroslav (referee) ; Kandus, Bohumil (advisor)
The goal of this project is design of manufacturing technology for door elastomer grommet in a series of 400 000 units per year. As a proposed solution of manufacturing technology has been chosen multicomponent injection moulding. Appropriate thermoplastic elastomer and polyamide was chosen based on the knowledge gained in theoretical study of materials and technologies elaborated in the second part of the project. Moreover, the shape of the door grommnet was redesigned in accordance with the chosen technology. Working machine was chosen from manufacturer Arburg, model Allrounder 630S in a two-shot design, complemented by the index unit. A cost of production of one piece of the door grommet was determined in an economic evaluation. This cost was compared with current cost of production and new technology reducing manufacturing costs of one series by 25%.
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Morphology of Polyamide 12 and Polyamide 11 formed at overpressure and underpressure
Bělašková, Marie ; Tocháček, Jiří (referee) ; Bálková, Radka (advisor)
In this master thesis it was studied morphology of polyamide 12 (PA12), polyamide 11 (PA11) and their blends in the percent ratios 95/5, 75/25, 50/50, 25/75 and 5/95 formed at pressure 7 MPa in a calorimeter both after continual heating and cooling and after annealing and isothermal crystallization. Neat polyamides and blends were further characterized by thermogravimetric analysis, differential scanning calorimetry at atmospheric pressure, Fourier-transform infrared spectroscopy in attenuated total refection, and X-ray diffraction analysis. The increased pressure improved level of polyamide chains ordering in crystal lamellae. Thermal annealing improved especially ordering of PA12, isothermal crystallization led to considerable increase of crystallinity, whereas PA11-rich blends supported perfection of PA12 crystals. Partial transformation of - to -structure occurred in case of neat PA12 at high pressure, the change of the chain conformation into the closer one occurred in neat PA11 without transformation of the type of crystal structure.
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Production technology of plastic base device with terminal
Horník, Tomáš ; Kebrle, Ondřej (referee) ; Kandus, Bohumil (advisor)
Master’s thesis deals with selection of a proper technology for manufacturing of chosen plastic part. The beginning of thesis contains part survey. Plastic injection was chosen as the most suitable manufacturing technology. Required theoretical knowledge for plastic injection mould designing were extracted in the recherche. Individual chapters deals with plastics, their manufacturing and plastic injection technology with all required knowledge about this technology, machines and moulds. Designing chapter contains every required calculation for mould design and all individual sections of mould design and injection machine selection. Injection simulations and their evaluations are part of this thesis aswell. Assembly and forms drawings as well as other documents used during thesis processing are included in the attachments.
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Study of electric properties of composite
Bariš, Marián ; Havlíček, Svatopluk (referee) ; Polsterová, Helena (advisor)
The theme of this Bachelor's thesis is a problematics of composite materials. On a given samples of polyamide with a various weight filling of a milled mica were measured resistivity, permittivity and loss factor on a consequence of a temperature and filling. The chosen type was a filling with a milled mica in range from 0 to 40 of a weight percentage, temperatures were in range from 20 °C to 90 °C.
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Production technology of the connector body from recykled material
Brhel, Michal ; Sedlařík, Vladimír (referee) ; Kandus, Bohumil (advisor)
Study developed during the Master's degree studies of Mechanical Engineering deals with the use of recycled plastic in the injection molding and its influence on the mechanical properties of the mold. Examined product is used in the automotive industry as a connector body. The housing is manufactured from a plastic material, polyamide. The annual production volume of 3 000 000 pieces. According to tests specified in standard USCAR2 regrind influence on mechanical properties and dimensions was evaluated. After the technical evaluation of the project, research was also judged from economic point of view. In this task, savings with the different content of the recycled material during production was calculated. The final chapters justify change of properties and they are proposing the use of recycled materials in practice.
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Effect of radiation cross-linking of PA on its thermomechanical properties
Mikel, David ; Tocháček, Jiří (referee) ; Jančář, Josef (advisor)
The influence of ionizing radiation on thermomechanical properties of polyamide reinforced by glass fibers was studied in this bachelor thesis. Ionizing radiation caused reduction of crystallinity, melting and crystallization temperature of polyamide. Tensile strength and tensile modulus increased due to irradiation, meanwhile elongation at break decreased. Notched and unnotched impact strength at laboratory and lower temperature increased with dose of radiation and after reaching the maximum it decreased for higher doses of radiation. Heat deflection temperature increased significantly with dose of radiation and after reaching the maximum it decreased for higher doses of radiation, too. Based on measured properties of investigated material was chosen optimal dose of radiation. Radiation rosslinking is an appropriate technology for increasing dimensional stability at elevated temperatures of polyamide reinforced by glass fibers.
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The influence of conditioning on the mechanical properties of polymers produced by injection molding technology
Neužil, Tomáš ; Řehořek, Lukáš (referee) ; Válka, Libor (advisor)
The aim of the thesis is to determine change of mechanical properties of three types of damp polymeric materials (polyamides) depending on the water content inside material. Before testing, specimens of all three types of materials were placed inside the air conditioning chambers until equilibrium (conditioned) state was reached when the specimens received the maximum possible amount of water from the environment. A total of three conditioning levels were set, representing besides the standard level of conditioning both extreme states like state when the material was fully dried and the state where the material content the largest possible amount of water. With the increasing content of water bound in material, there is a characteristic change in the mechanical properties of the material, such as a decrease in strength and modulus of elasticity and an increase in toughness and ductility. To examine material properties change, tensile and Charpy impact tests were performed, Charpy impact tests were performed for both specimens with and without a notch. Besides changes in mechanical properties, the rate of water absorption was also observed depending on the materials and its filling.
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Corrosion resistance of PA and PC components
Mikel, David ; Pospíšil, Ladislav (referee) ; Jančář, Josef (advisor)
The influence of two lubricating and cleaning agents and diesel fuel on environmental stress cracking of polyamide reinforced by glass fibers and polycarbonate was studied in this master thesis. Testing of environmental stress cracking was performed by the method of critical bending deformation. Bergen elliptical strain jig was used for testing. The test liquids caused varying levels of environmental stress cracking of amorphous polycarbonate, but they did not cause environmental stress cracking of glass fiber reinforced polyamide. The test method used allows testing the resistance of both materials against environmental stress cracking of any liquid. The results can be used to design products that are expected to be exposed to corrosive liquids. Quantification of the influence of stress free corrosion on the static and impact properties of polycarbonate and glass fiber reinforced polyamide was performed by accelerated test. Specimens were exposed to test liquid and an elevated temperature of 70 °C. The mechanical properties of the tested materials were significantly affected by elevated temperature exposure. The yield strength of the polycarbonate has increased and the toughness has decreased due to physical aging. The tensile strength of glass fiber reinforced polyamide has increased due to a decrease of the moisture content of the material.
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Production of components 'COVER'
Václavek, Jiří ; Kandus, Bohumil (referee) ; Žák, Ladislav (advisor)
The theory of plastic injection molding technology together with procedure of designing injection molds is elaborated in this master thesis. Also, the technology of production is designed, derived from assigned component „cover“ analysis affirmed by necessary calculations. On the bases of these calculations, injection machine fitting requirements is chosen. Then injection mold is designed for the assigned component. Simulation of injection is performed for this mold using Autodesk Inventor 2011 and its module Moldflow and then results are thoroughly analyzed. Economical evaluation for this component is then executed towards the end of the thesis.
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Design of manufacturing technology for plastic cover electrical device
Kočárek, Karel ; Kebrle, Ondřej (referee) ; Kandus, Bohumil (advisor)
This thesis contains of theoretical part which deals with injection molding, properties of some polymer materials are included also. Design of plastic injection mold for cover of electronic device is presented in practical part. Manufacturing parameters and injection machine selection are specified with mold structure consideration. Production costs and the final price of the plastic part are calculated in economical evaluation.
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