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Technology of waste polylactide recyclation for 3D print
Kecíková, Alžbeta ; Tocháček, Jiří (referee) ; Přikryl, Radek (advisor)
This bachelor thesis deals with the recycling of waste polylactide from the production process and its subsequent use in 3D printing. To optimize the recycling process of polylactic acid, it was recycled with the addition of various additives such as poly(3-hydroxybutyrate), talc, limestone and chain extenders Joncryl 4368-CS and Raschig Stabilizer 9000. These materials were also investigated with the addition of the acetyl tributyl citrate plasticizer. Samples of the mixtures were prepared on a twin-screw extruder and subsequently a filament was obtained using a single-screw extruder, which was then used for 3D printing by fused deposition modelling (FDM) technology. Temperature towers were printed to obtain optimal processing temperatures for 3D printing. The effect of the additives on the characteristic temperatures and the degree of crystallinity of the PLA was determined by differential scanning calorimetry. The effect of the processing on the molecular chain of selected samples was observed by gel permeation chromatography. Furthermore, in the experimental part of the bachelor thesis, the influence of additives on mechanical properties such as modulus of elasticity, tensile strength and elongation was investigated. The molecular weight was increased due to the chain extenders. Of the particle fillers for the PLA matrix, talc had better mechanical properties than limestone. The greatest effect of the plasticizer was in a mixture with poly(3-hydroxybutyrate).
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Manufacturing of a connecting pin by cold forming
Koumar, František ; Peterková, Eva (referee) ; Jopek, Miroslav (advisor)
The diploma thesis is focused on the optimization of the production of a rotary connecting pin, produced by bulk cold forming with a focus on upsetting and forward and backward extrusion. The resulting pin will be made of 1.4511 steel. From the three proposed variants of production processes, the optimal variant for four forming operations was selected. Extrusion tools are made of tool steel 19 830. A numerical simulation was performed to verify the suitability of the sequence of the selected variant. The size of the production batch is set at 700,000 pieces / year. In the technical and economic evaluation, the calculated production price of 1 piece of part was coMPared between machining and volume forming, at which the production costs amount to CZK 6,64. The return on this method, with an assumed profitability of 10%, was found for 568 182 pieces produced.
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Static solution of parking house
Rose, Dominik ; Koláček, Jan (referee) ; Zich, Miloš (advisor)
The bachelor's thesis is focused on the elaboration of a static solution of a parking house with four above-ground floors. Three variants are elaborated, one of which was elaborated in more detail. The proposed elements are the ceiling slab, the columns and staircase. The SCIA Engineer 20.0 program is used to calculate the internal forces. As part of the work, drawing documentation is also prepared. The structure is designed according to correctly valid standards.
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Bulk forming technology of carrier pin
Večeřa, Jiří ; Samek, Radko (referee) ; Forejt, Milan (advisor)
This thesis deals with a proposal of a technology for manufacturing a carrier pin made of corrosion resistant chrome steel 17 021.3. Having studied the information about cold bulk-metal forming in the available literature, I have suggested two variants of manufacturing processes. The suggested manufacturing variants consist of four forming operations which combine upsetting and extrusion. As far as the chosen variant is concerned, there have been made technological and strength calculations for the individual operations. As regards the designed technology, I have opted for the automatic multistation forming machine TPZK 25, produced by the company ŠMERAL Brno.
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Bulk forming technology of connecting pin
Trnka, Filip ; Šlais, Miroslav (referee) ; Forejt, Milan (advisor)
The project elaborated in frame of engineering studies branch M-STG proposes a technology of connecting pin – structural steel 11 320 5R. The technological calculations were performed and the production procedure was devised on the basic on the literary study of cold bulk forming with concentration on the extrusion and upsetting. Forming machine was design HATEBUR BKA-3 with a nominal power 1800 kN. The component is made in four forming operations. Extruder will be made from tool steel 19 830, extrusion die from tool steel 19 830 and clamp ring from tool steel 19 740.
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Design of underground garage in Brno
Hájek, Jan ; Hladík, Pavel (referee) ; Zich, Miloš (advisor)
The goal of the project is behaviour and dimensioning of selected monolithic concrete structure elements. Design and assessment of the building foundation was made. Slabs of the floors are dimensioned in detail. All computations are made in accordance with Eurocode 2. Drawing documentation is part of this project.
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Concrete flat slab supported by columns
Járik, Enikő ; Švaříčková, Ivana (referee) ; Perla, Jan (advisor)
The aim of bachelor theses is to find out the internal forces on the point-supported reinforced concrete flat stab of a hospital buildingon the first floor.The analysis was performer using the following method: finite element method in Dlubal´s RFEM program, result were proved by the equivalent frame method. The structural assessment was performer according to ultimate and servicable limit states. The work also includes the desing of one column.
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Manufacturing of swivel pin
Vávra, Roman ; Šlais, Miroslav (referee) ; Řiháček, Jan (advisor)
The thesis deals with the design of a suitable technology for serial production of a pin. The component material is structural steel 11,320 5R. Due to the series production and material savings, the molding technology was chosen to be cold. For production, the CM 4-5 ECO HATEBUR process press was designed with a nominal force of 1 700 kN. Progressive tool and drawing documentation of tools for the final operation were also designed. The tool load was verified by manual calculation, and the finite element method was calculated to heat the formed blank due to molding.
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Effective management of plastic waste
Kostková, Kateřina ; Pavlas, Martin (referee) ; Gregor, Jiří (advisor)
The main content of the submitted diploma thesis is the implementation of analysis of separated plastic waste and examination of the issue of extrusion tests. The practical knowledge is preceded by a search of waste management in the Czech Republic and get acquainted with the issue of polymer materials. The research is about plastic waste management and preparation of polymeric materials for extrusion tests. Theoretical knowledge is then applied in the practical implementation of extrusion tests.
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Design of optimization of extrusion process control tests
Pavlíková, Michaela ; Šrámek, Jan (referee) ; Maradová, Karla (advisor)
The master´s thesis is focused on the optimization of extrusion process control tests. The practise was performed at Fraenkiche CZ s.r.o., which is a company specialising in plastic tubes and components. The aim of the master´s thesis is to analyse the current state of the specific issue, systematically analyse the topic, statistically analyse and discuss the results and propose a new method of extrusion process control tests with my recommendation for practise. The introduction forms a preview into the quality management, plastic materials and processing of them. The practical part contains an analysis of the company and their production process. This information was helpful to the design of a list of control tests. With the help of basic quality tools, I prepared a new design of a list of control tests. The basic statistical processing showed an evaluation of finance savings. In the final part I evaluated the results and proposed several recommendations for improving current processes in the company.
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