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Production technology of plastic parts for automotive industry
Šobáň, Jakub ; Ohnišťová, Petra (referee) ; Žák, Ladislav (advisor)
The diploma thesis presents a production technology design of an automotive industry component – a resonator holder. The initial production run of the part is 500 000 pcs. Injection production has been selected based on variant analysis of available technologies. Technological calculations have been performed. The selected material PP 56M10 will be used for operation in granules. A quadruple shaped cavity injection mold with a tunnel gate has been designed. Based on estimated technological properties an Arburg Allrounder 470 A machine has been selected. The break-even point (BEP) shows economic return at the production of 185 595 pcs.
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Technology of injection molding of thermoplastic test specimens
Khamzin, Yersin ; Petruš, Josef (referee) ; Kučera, František (advisor)
The diploma thesis focuses on the optimization of technological parameters of plastic injection molding and the study of the influence of technological parameters on the quality of molded test specimens’ type 1A. The quality of molded parts for 3 types of polypropylene (PP) with different melt flow rate (Mosten GB 002, Mosten GB 218, Mosten MA 230) and 1 type of polystyrene (PS) (Krasten PS GP 154) was evaluated in terms of dimensional stability and weight. The contribution of software for modeling the plastic injection molding process was evaluated in this work. SOLIDWORKS Plastics software was used to optimize technological parameters. The construction of the bodies, mold and cooling system was constructed, and test bodies were produced on the basis of parameters obtained from the simulation of the injection molding process. Their quality parameters were compared with a 3D model and for each of the studied materials the optimal technological parameters were selected in terms of quality and the degree of influence of individual injection parameters on the quality of moldings was evaluated. The accordance of the results of the theoretical simulation with the real experiment was proved and a computational module independent of the optimized quality parameters, generally suitable for optimizing the quality parameters of the injected parts, was developed.
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Production of HTHT32 / 40 GI Double Elbow
Kříbala, Milan ; Kandus, Bohumil (referee) ; Žák, Ladislav (advisor)
The diploma thesis deals with the design of an injection mold for manufacturing double elbow, which finds its use in the siphon assembly. The part will be made of polypropylene with the trade name Tatren HT 25 11. The production batch size is set at 100,000 units in 3 months. Firstly, the analysis of the part is done including a detailed specification of its function and criteria that must be met by the component. Furthermore, a suitable technology for the production of the part is chosen. The theory of injection molding and mold design is made on the basis of the chosen injection technology. Subsequently, in the practical part is made a complete design of injection mold including technological calculations and simulations. An injection molding machine is chosen for the proposed injection mold. The conclusion of the thesis consists of technical - economic evaluation of the production of double elbow.
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Preparation of PP composites by grafting using monomer treated filler
Kramerová, Nina ; Žídek, Jan (referee) ; Kučera, František (advisor)
Bachelor thesis is focused on preparation of composite materials with polypropylene matrix. The composites were prepared “in situ” with using Brabender mixer. Homogenization of matrix and filler and grafting of PP with anhydride of itaconic acid treated filler proceed together according to radical mechanism of polymerization. Luperox 101 [2,5-dimethyl-2,5-di(tertbutyl-peroxy)hexane] was used as an initiator of the reaction, the concentration of the initiator was 0.5 wt %, processing temperature 210 °C, 30 rpm. PP-g-IA is a compatibilizer between the matrix and the filler. Glass fibers, calcite and two types of ground wood pulp were used as filler. Two analytical methods were chosen to analyze the efficiency of grafting, acid-base titration and infrared spectroscopy. Assigned conversion of monomer was from 42 to 87 % for various fillers.
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Polymeric biocompatible materials
Matlák, Jiří ; Stránský, Lubomír (referee) ; Molliková, Eva (advisor)
The aim of the bachelor’s thesis is polymeric biocompatible materials. In the first part the problematic of the biocompatible materials is discussed and the basic terms are explained. In the next part are described polymeric materials and their chemical composition, mechanical and chemical properties and examples of applications.
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Description of the residual stresses in polymer pipes
Poduška, Jan ; Majer, Zdeněk (referee) ; Hutař, Pavel (advisor)
This thesis is dealing with the issue of residual stress present in the wall of a polymer pipe and the influence on its lifetime. Experimental data obtained by the ring slitting method are evaluated and the tangential residual stress in the wall of polypropylene pipe is determined. The evaluation is carried out using a new methodology based on the curved beam theory. The method is verified using numerical simulation. 3D numerical model is used to verify the behavior of the pipe, when there are both tangential and axial residual stresses present in the pipe wall, because the presence of axial stress causes a rise in the magnitude of tangential residual stress. A correction of the tangential stress values corresponding to the pipe length is then proposed. It is shown, that the distribution of the tangential residual stress does not depend significantly on the dimensions or ma-terial of the extruded pipe and a general equation is proposed to describe the distribution. This general distribution is then involved in the calculations of the pipe lifetime that are carried out using a method based on the linear elastic fracture mechanics. A significantly lower lifetimes are obtained when taking the residual stress into account.
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Controlled life-time polypropylene
Demková, Eva ; Petruš, Josef (referee) ; Tocháček, Jiří (advisor)
The master´s thesis is focused on the characterization of degradation process of polypropylene and polypropylene with statistic copolymer into which manganese (II) stearate and cobalt (II) stearates were added at 0.05, 0.10 and 0.20 wt.% loadings. The aim of the thesis was to prepare the controlled life-time polypropylene. The degradation was studied at varying temperatures and prodegradant loadings. The prodegradants were synthetized and characterized using the FTIR and DSC techniques. Thermooxidation of the tested samples induced the changes in crystallinity, melting points and melt-flow indexes. Tensile strength and other mechanical properties were determined by means of the tensile test. The carbonyl index was determined using FTIR, the thermooxidation stability test was used to determine the activation energies of reactions. The changes in morphology of degraded samples were observed by SEM analysis.
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Production single parts from thermoplastic
Ruibar, Jakub ; Kandus, Bohumil (referee) ; Žák, Ladislav (advisor)
The project developed in terms of engineering study of field N2307-00 Engineering Technology submits a design of components from plastic production technology – centre ring of labels on CD. In literary study there are summarized the basics of technology issues in elaboration of plastics injection into the metal form. The work includes production of component technology assessment and design of component production technology. Furthermore, the work includes the design of constructional solutions injection form, the option of suitable material of injection and the injection machine as well as the economic classification of production. As part of this diploma work is also considerations process of injection through the use of simulation program Moldex3D. This work is supported by appropriate drawing and appended documentation.
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Way of assign of stereoregularity of polypropylene
Hoza, Adam ; Tocháček, Jiří (referee) ; Kratochvíla, Jan (advisor)
The purpose of this work is to evaluate and compare isotactic index value determination of polypropylene homopolymer using extraction and solubility methods. A series of nine PP samples in a powder form specified by molecular weights in the range from 29 to 154 kg/mol was investigated. The methods afforded separation of polypropylene into two portions, the soluble fraction, and the insoluble one. Extractions were carried out in a modified Kumagawa extractor. Polypropylene extracts were obtained using several organic solvents (pentane, hexane, heptane, and octane) at their boiling points. Soluble fractions were obtained by dissolving the PP sample in high boiling point solvents (xylene, decahydronaphthalene, and 1,2,3,4-tetrahydronaphthalene) and cooling the polymer solution to 23°C. All the fractions were characterized using 13C-NMR, SEC, and DSC methods. Comparison of the extraction and solubility methods showed significant differences in the amount, stereochemical structure, molecular weight, and crystallinity of soluble, and insoluble fractions.
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Physical ageing of polypropylene
Weiss, Jiří ; Kučera, Jaroslav (referee) ; Tocháček, Jiří (advisor)
Physical aging of commercially produced polypropylene homopolymers Mosten was studied. The work is focused on monitoring the changes in physical properties of polymer in the time period 90 days from the date of preparation of the test specimen. The aging of polymers was realized at storage temperatures of 23 and 80 °C. The changes in crystallinity, yield strength, modulus, elongation and impact strength using DSC method, tensile tests and impact tests according to Charpy were monitored. Molecular weight distribution was determined by means of GPC at each polymer. Relationships between the changes in physical properties and polymer molecular weight were sought.
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