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Production of a clamp
Svoboda, Petr ; Forejt, Milan (referee) ; Podaný, Kamil (advisor)
The thesis presents a proposal for the production technology of the clamp in the company FERRUM s.r.o. It is used to connect floor grates to the supporting structure. It is manufactured from 2 mm thick DC01 sheet metal in a series of 3,500 pieces per month with subsequent surface treatment in the form of hot-dip galvanizing. From the proposed production possibilities, the technology of shearing and bending in a combined tool was chosen. Production takes place in four steps, in the first the outer contour is trimmed, in the second the short arms are bent, in the third the hole for the screw is cut, in the last the long arm is bent, and the part is separated from the rest of the blank. The design of the tool has been developed considering the production capabilities of the company's machining centre. These include turning, milling, drilling and grinding. The production requires a forming force of 387 kN and will be carried out on a LEN 63 C eccentric press located in the company's machine park.
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Application of drawingless documentation in the design of a milling clamping device
Schneider, David ; Michalec, Michal (referee) ; Svoboda, Petr (advisor)
The bachelor's Thesis describes the construction of a milling fixture for clamping a component on a machine tool using drawing-less documentation. Available methods of clamping workpieces for machining are described here, and the creation of drawing-less documentation is further explained. Today, in the vast majority of cases, classic drawing documentation is used, which is in many ways more tedious than the processing of described 3D digital data about the model. The work describes the creation of drawing-less documentation on a specific design solution of a milling clamping device. This solution is developed on the basis of three proposals for possible conceptual solutions for the clamping fixture. Complete, drawingless documentation of all individual parts of the product. The bachelor's thesis shows the advantages of drawing-less documentation compared to 2D drawings of components, but also mentions shortcomings that reduce the overall impression. A possible improvement that could simplify the presentation of digital model data is suggested.
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Wear analysis of the sliding surface material of large-scale hydrostatic bearings
Daněk, Lukáš ; Robenek, Dětřich (referee) ; Svoboda, Petr (advisor)
This thesis focuses on the experimental investigation of the wear behavior of sliding surface materials in large-scale hydrostatic bearings during oil supply failure. The aim is to clarify the influence of materials and surface treatments on friction and wear. For this purpose, a testing methodology was designed and implemented in laboratory conditions. An experimental module was developed for the tribometer to simulate a critical state and a new procedures were established for evaluating the behavior of the contact. Wear results were observed using a profilometer, precise scales, and a microscope. A set of suitable materials for pad sliding surfaces was created, which were tested under critical conditions. The selected materials were representatives of construction steel and anticorrosion treatments (galvanization), soft and hard (aluminium) bronzes, composite bearing linings (Babbitt), polymers (UHMWPE), and composite materials (PTFE). The experimental results show the dependence of friction on sliding velocity, wear rate, and other phenomena repeatedly measured on a statistical sample of selected materials. The final result is a list of characteristics, limitations, and recommendations for the tested sliding materials, which can be used for more effective design and operation of large-scale hydrostatic bearings.
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Bevel gearbox design for heavy industrial applications
Škopec, Filip ; Vlašic, František (referee) ; Svoboda, Petr (advisor)
The thesis deals with the problem of bevel gearboxes on the Czech and foreign markets, where there is no offer in a wider range of required properties and specifications. The main goal of the thesis was to devise a design solution for a two-stage bevel gearbox for belt conveyor mine operation with parameters: P=37 kW, n=1450 rpm, i=20 and operation in a dusty environment. Based on the analysis of the current state of knowledge, which dealt with the main components of bevel gearboxes, four conceptual solutions were created from the point of view of the arrangement of individual gears. From the individual comparisons of the appropriateness of the use of the given conceptual designs, a design with a modified gear-case was selected, which was processed using design calculations and subsequently checked by strength calculations. The output of this thesis is processed production drawings of shafts, bevel and spur gear and then a drawing of the bevel gearbox assembly. The thesis also includes a written general procedure for the design of bevel gearboxes, which can serve as a guide for readers. The resulting construction design can form the basis for the final product of companies that would deal with a potential order.
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Drawingless documentation in engineering
Ronďoš, Radim ; Pouzar, Josef (referee) ; Svoboda, Petr (advisor)
This bachelor thesis deals with the research of the use of drawingless documentation in mechanical engineering. Drawingless documentation, or Model Based Definition (MBD), enables the transition from 2D engineering drawings to 3D CAD models annotated using machine readable annotations, the so-called PMI data. This thesis addresses both its use in industrial applications and its preservation using appropriate CAD formats. Studies especially in the field of inspection show positive results of MBD application in industry. For the proper functioning of PMI it is crucial that this data is reliably transferable. Therefore, this thesis investigated the portability of PMI data to GOM Inspect from a test component in the form of a bearing rack. The drawingless documentation in STEP AP242 format was compared with the scanned mesh of the part produced by 3D printing. 47 % of the generated PMI was successfully imported and evaluated. Human intervention would be required to transfer all the data, which could introduce errors into the transfer, and therefore these shortcomings must be minimised for companies using MBD. The findings were presented and discussed at the end of the paper.
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Design with respect to production costs
Homola, David ; Omasta, Milan (referee) ; Svoboda, Petr (advisor)
This bachelor’s thesis analyse general principles of Design for cost strategy in parts manufacturing. Compared manufacturing processes are Machining, Casting, Welding and 3D Print. Each process is rated based on production costs which are influenced by amount of manufactured parts, material, shape complexity, achieved tolerances and surface quality. Those informations are than applied in construction design of chosen part for each process separately. Each design is than compared based on production costs for specific amount of manufactured parts.
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Molluscs as a new model system in molecular biology
Ber, Tobiáš ; Svoboda, Petr (advisor) ; Pergner, Jiří (referee)
Molluscs form the second largest animal phylum and are of great biological and economic significance. Their distinct evolutionary adaptations enabled them to inhabit a broad range of environments, with many of them invading new areas and becoming invasive pest species. Despite their importance, molluscan model systems have not received attention they deserve. In this bachelor thesis, I have reviewed the current state of molluscan model systems in molecular biology and analyzed their significance for more common use. From available data, it is apparent that the already established molluscan models are either marine or fresh-water, and therefore require more complex logistics and maintenance in order to set up a laboratory culture. To remedy the problem of aquaculture, the use of terrestrial gastropods was proposed. Here, I suggest that gastropods genus Deroceras have a good potential to become a new prominent molluscan model system in molecular biology.
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Felling woody plants which grow outside of the forest and a transport infrastructure
Bilanin, Petr ; Rajchl, Jiří (advisor) ; Svoboda, Petr (referee)
Felling woody plants which grow outside of the forest and a transport infrastructure Abstract The subject of this diploma thesis is a legal regulation of felling woody plants located near road and rail transport infrastructure. It focuses mainly on the analysis and evaluation of the current legal regulation of this area, together with de lege ferenda proposals that could lead to the improvement of this legal regulation. This thesis is divided into three sections, which are further divided into individual chapters and subchapters. The first section is focused on the description of the general legal regulation of felling woody plants which grow outside of the forest. This general legal regulation form the basis of special legal regulations of felling woody plants located near road and rail transport infrastructure. In this section there is an illustration of the central concept of woody plants which grow outside the forest, an exploration of three basic principles of this regal legulation and, above all, a description of the individual regimes under which it is possible to fell woody plants. Special protection regimes of woody plants which grow outside of the forest are also briefly discussed. The second section is dedicated to the felling of woody plants which are located near road infrastructure and related...
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Public administration bodies in the capital city of Prague
Zemanová, Eliška ; Vedral, Josef (advisor) ; Svoboda, Petr (referee)
Public administration bodies in the capital city of Prague Abstract The thesis deals with the organization of public administration in the capital city of Prague. Its aim was to give a comprehensive overview of a not very often treated issue and to touch upon the unclear position and legal nature of the city district. The intention is to highlight some controversial issues. After the necessary introduction to the issues of the public administration bodies, the thesis deals with the historical context of the public administration bodies in the capital city of Prague. The following chapter deals with the legal regulation of the public administration bodies in Prague, and the fourth chapter deals with public administration bodies in a narrower sense. The thesis describes the position of the individual bodies of the capital city of Prague and the bodies of the city districts and analyses the performance of local self-government and state administration in the environment of the capital city of Prague. A sub-objective is to open a controversy regarding the legal nature of the City of Prague. The question of whether a municipal district is a sui generis public law corporation is controversial. The analysis has shown that the opinion on the legal nature of the municipal district is hardly anchored at all. Thus,...
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The role of microRNAs in regulation of mammalian oocyte and embryo development
Marcollová, Kateřina ; Procházka, Radek (advisor) ; Svoboda, Petr (referee)
Cumulus-oocyte complex (COCs) is crucial for mammalian reproduction. Cumulus cells not only nurture the oocyte; they also represent important communicational nodes for mediating information towards and from the oocyte. The non-coding miRNAs can modulate posttranscriptional events they might serve as a useful biomarker for evaluating cell conditions. Based on the COCs staining with vital Lissamine Green B stain we divided cumulus cells into high- and low-quality ones. Furthermore, we implemented division based on the maturation stage, the GV and MII. Sequencing data analysis showed that DE miRNAs from qualitatively different stages donot significantly vary. Nonetheless, significantly DE miRNAs were detected between two developmentally different stages. We identified e.g. ssc-miR-183, ssc-miR-182, and ssc-miR-21-5p to be highly downregulated when comparing GV to MII stage. Among the highly expressed miRNAs from all samples were members of let-7 family (let-7c, let-7a, let- 7f-5p), ssc-miR-16, ssc-miR-21-5p, and ssc-miR-125a. Targeted genes by the DE miRNAs were involved in ErbB, TGF-β, MAPK, FoxO, gap junction and cGMP signalling pathways. We conclude that single miRNAs in cumulus cells probably cannot be used as a reliable oocyte quality marker. On the other hand,changes in the miRNA expression in...
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