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The production of a gully
Králíček, Václav ; Jopek, Miroslav (referee) ; Peterková, Eva (advisor)
Aim of the thesis is possible innovation in production of a body of floor gully. Material of the gully is an austenitic stainless steel 1.4301 (X5CrNi18-10). This particular gully belongs to floor drainage portfolio of ACO Industries k.s., which is a world leading company in drainage systems. The current welded variant has been replaced by a combination of conventional drawing and dimpling. The geometry of the drain bottom was designed in accordance with the requirements of the ČSN EN ISO 14159 standard and EHEDG documents on the hygiene of equipment for use in the food industry. Technological calculations were made for the new designed geometry, the bottom of the inlet will be made in one drawing operation together with the dimpling of the pre-made hole. The production process was verified using numerical simulation. Part of the solution was the production of a prototype for testing of the flow rate. During the flow rate test, the requirements given by the standard were fulfilled. Combined tool for drawing and dimpling was designed. The tool is designed for use in hydraulic press Dieffenbacher PO250 II with magnetic tool clamping. The financial savings compared to the current floor drain design are about 243,43 CZK. With a specified production series of 700 pieces per year with an expected increase of 15 % in the following years, the return on investment for the purchase of the tool was calculated to be 2,65 years.
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Design for Manufacturing of Wheel Hub Cover
Kunc, Ondřej ; Jopek, Miroslav (referee) ; Řiháček, Jan (advisor)
The thesis deals with the design of the production of a wheel hub cover made of 17 350 stainless steel. The cover is in the form of a cylindrical cup with a diameter of 74.5 mm with a flange and a depression in the bottom. The wall thickness is a constant 1 mm. For the production of the series of 100 000 pieces was chosen conventional deep drawing technology. The choice of the technology is followed by technological calculations. The part will be produced in three drawing operations followed by a calibration operation. Verification of the manufacturability of the proposed process was carried out by numerical simulation in PAM - STAMP software. All operations including blank cutting and flange cutting will be performed in one tool clamped in a Dieffenbacher PO 250 hydraulic press.
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Effect of strain rate on the mechanical properties of materials
Gajdošík, Matej ; Forejt, Milan (referee) ; Jopek, Miroslav (advisor)
Metóda Taylorovho testu je využívaná na skúmanie vlastností materiálu za podmienok dynamického zaťažovania. Práca predstavuje kompletný proces vývoja, montáže a testovania nového testovacieho zariadenia zameraného na dosiahnutie symetrického nárazu dvoch vzoriek materiálu v pohybe. Zariadenie je testované v dvoch konfiguráciách, pričom sú opísané výsledky oboch. Boli vykonané materiálové testy smrekového dreva, ktoré boli následne porovnané s výsledkami získanými z klasického Taylorovho kanóna. Boli zistené a opísané podstatné rozdiely. Ukázalo sa, že vykonané simulácie symetrického nárazu s využitím modelu smrekového materiálu nezodpovedajú praktickým experimentom, čo naznačuje potrebné zmeny modelu.
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Standardization of the copper technological forming process
Březina, Tomáš ; Císařová, Michaela (referee) ; Jopek, Miroslav (advisor)
The thesis focuses on the optimization of bending copper busbars in the Brno branch of the company ABB s.r.o. Busbars serve to conduct electricity and are used in high-voltage switchgears. The semi-finished busbar products are made of electrolytic copper that complies with the EN 13601 standard. Busbars are produced in various shapes and sizes according to the specifications of the switchgear. Part of the thesis involves a tensile test to determine the mechanical properties of electrolytic copper. A practical bending test was performed on a bending machine for bars with different mechanical properties. The entire bending process was simulated in Ansys Workbench software. Using the simulation, the tool stroke was optimized to achieve the desired deviation from the nominal angle. The optimized stroke was subsequently used on the bending machine to achieve the required bending accuracy.
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Mechanical behaviour of Strenx steel at high strain rates
Basler, Matěj ; Forejt, Milan (referee) ; Jopek, Miroslav (advisor)
The thesis is focused on the description of the behaviour of high-strength steel Strenx under quasi-static and dynamic conditions with emphasis on the influence of anisotropy. A compression test was used as a low strain rate test with specimens formed from rolled sheet in the 0, 45 and 90 degree directions relative to the rolling direction. The behaviour of the steel at high strain rates was described using the Taylor impact test, again with specimens oriented with respect to the rolling direction. The contour of the deformed specimens from the dynamic test was measured by image analysis and the dynamic yield strength of Strenx steel was calculated. The test results were compared between the loaded directions and the anisotropic behaviour of the material was described. From the values obtained from the performed experiments, the material constants for Johnson-Cook's material model were determined and its reliability was compared with both quasi-static and dynamic test results. The calculated values using the material model achieved satisfactory accuracy and the developed material model can be considered reliable.
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Production of gear shaft
Zahálka, Tomáš ; Řiháček, Jan (referee) ; Jopek, Miroslav (advisor)
The work is focused on the design of the production of the transmission shaft semi-finished product, with a closer focus on the transverse wedge rolling method. The manufactured part with the largest dimensions of 80 mm and length of 322.7 mm is made of steel 15,230, with a total series of 200,000 pieces per year. The work first focuses on the theoretical part, in which the mentioned technology, which belongs to the volume hot forming methods, is researched in detail. This is followed by a practical part with the necessary technological calculations, tool design, its verification by simulations and technical-economic evaluation. The tool is designed as a circle, consists of an upper and a lower part that have the same sense of rotation, and is dual-operation. The roll becomes profitable after reaching 186 517 pieces, at a price of CZK 368 per piece.
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Manufacturing of a Coupling Body
Dostál, Martin ; Jopek, Miroslav (referee) ; Řiháček, Jan (advisor)
The thesis deals with the design of the production of the clutch body. The production company is Zetor Kovárna s.r.o. It is a slightly more complex component used in the automotive industry. The production run is 80,000 pieces per year. The material for production is lowcarbon steel 12 020. Of all the evaluated production technologies, production by hot die forging is chosen. A suitable shape of the forging is also designed for it. The input blank is a rod with a diameter of 100 mm and a height of 201 mm. The proposal also deals with the cutting and preheating of the input blank. Die forging is designed in three steps. The selected forging force for the last operation is 30.7 MN. The proposed production press is the LZK 4,000. The LKOA 200 press is selected for finishing cutting operations.
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Optimization of infill selection with an emphasis on maximum dynamic resistance
Konvalina, Michal ; Svoboda, Petr (referee) ; Jopek, Miroslav (advisor)
The thesis deals with the study of the effect of different wall thicknesses of 3D printed infill patterns at constant cross-sectional area on their final properties under static and dynamic loading. Based on literature study, two experimental methods are chosen. The quasi-static test and the Taylor anvil test. For the experiment, square and hexagonal grid specimens are printed using FDM technology from PLA material. Quasi-static test is used to measure the static properties such as maximum compressive strength, yield stress, modulus of elasticity and to derive material model of Johnson-Cook. The dynamic impact test TAT is used to evaluate different types of patterns at high impact velocities. In ANSYS, the specimens that resisted the highest impact velocities in TAT are simulated and strain rate sensitivity parameter is optimized for the specific velocity. The highest dynamic resistance was achieved by a square infill pattern with wall thickness of 0,4 mm at an impact velocity of 37 ms-1.
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Development of the HSBT tensile impact test equipment
Pech, Vladimír ; Harant, Martin (referee) ; Jopek, Miroslav (advisor)
The thesis is focused on the design of a device for tensile impact tests based on the Hopkinson's split bar principle. The theoretical part describes the behaviour of materials under dynamic loading conditions and a description of the testing methods used. The thesis describes in detail the Hopkinson tensile test and different design variants of this device, including their principle, advantages and disadvantages. In the practical part of the thesis is designed the testing device and the individual parts of the device are analyzed. For the key parts, the selection of materials and geometric parameters is described to ensure the proper functionality of the device. The constructed device is tested by samples made from PETG material. Capacitive sensors and strain gauges were used to record data during the test to verify the correct functionality of the device.
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Development of a test specimen carrier for a symmetrical impact test
Hoffman, Petr ; Forejt, Milan (referee) ; Jopek, Miroslav (advisor)
The thesis focuses on the development and optimization of a wooden specimen carrier for the symmetric Taylor test. It includes a detailed description of dynamic material tests, internal ballistics of the projectile, and labyrinth seal. The thesis summarizes the history of the carrier development for the Taylor test and analyzes its current state. A new carrier for the symmetric Taylor test and wooden specimens with a square cross-section was developed. Using simulations and tensile tests, the ultimate strength for the given carrier was determined. Subsequently, the thesis addresses the design and impact of the labyrinth seal on the carrier's velocity, which was designed based on simulations in the ANSYS program and practically tested in the Taylor test
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