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Heat treatment of formed parts
Leška, Radim ; Jopek, Miroslav (referee) ; Lidmila, Zdeněk (advisor)
In the research part, the bachelor thesis deals with forming, the mechanism of plastic deformation and steels used for forming. It also describes the principles of heat treatment, specifically the methods used in the preparation of semi-finished products, pressings, and forgings, i.e., annealing, hardening, and tempering. In the practical part, several experiments were performed on C45 steel. The first of them verified the effect of strain hardening after compaction, the others were focused on recrystallization, full annealing, hardening, and tempering. The effect of deformation and heat treatment was assessed in terms of hardness, which was measured by the Vickers hardness test.
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Development of an impactor for the Taylor anvil test
Müller, Samuel ; Forejt, Milan (referee) ; Jopek, Miroslav (advisor)
The Master Thesis describes the differences between quasi-static and dynamic material tests and discusses the effect of strain rate in forming processes. It contains a detailed description of Split Hopkinson pressure bar test, Split Hopkinson tensile bar test and Taylor anvil test. The thesis contains a basic theory of ballistics and the history of the development of the material sample carrier for the Taylor test and the analysis of its current state. A new sample carrier was developed for the adjusted diameter of the Taylor test equipment. The shape of the carrier was designed, based on simulations in ANSYS software and practical testing. The carrier was made by 3D printing technology, FDM method. Samples of aluminum alloy 2024-T3 were tested using the new samples carriers. Dynamic flow stress was determined, and the strain rate constant was optimized for specifics impact velocities.
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Manufacture of Chandelier Hinge
Mergeščíková, Lenka ; Jopek, Miroslav (referee) ; Žák, Ladislav (advisor)
The master’s thesis presents a design for the technology of manufacture of a chandelier hinge from the material ČSN 42 3005 (Cu99.5) with a sheet thickness of 0.5 mm. Due to the spherical shape of the part and the series 40 000 parts per year, the technology of deep drawing was chosen for two drawing operations, while the redrawing is performed by reverse deep drawing. Due to the nature of the component, the additional technology is shearing. The manufacturability of the part was verified using numerical simulation in the PAM-STAMP software. The forming process is performed using three forming tools on three different presses. For the first, combined tool, an LE 160C eccentric press is used. A hydraulic press ZHO100 is applied in the second tool for the reverse drawing, and finally, an eccentric press LEK160 is applied for the shearing in the third operation. With the selected profit value of 25 %, the final price for the component was set at CZK 104.17. The turning point occurs after reaching 16 248 parts.
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Production Possibilities of Press Brakes
Hrazdíra, Michal ; Jopek, Miroslav (referee) ; Řiháček, Jan (advisor)
The bachelor thesis deals with the production possibilities of press brakes. This is a literary research, in which the aim of the work is to describe the principle of bending. It also focuses on common and special tools and their use in engineering practice. The first part of the work is focused on general bending technology, which discusses the basic principles and possibilities of this method. The main chapter is the bending itself, where the individual types of machines, their components, tools and clamping systems are introduced and described. Furthermore, modern tools and their application in engineering practice are presented. In the last part, the production of the switchboard cabinet is presented on a CNC press brake.
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Simulation of machining operation using explicit FEM
Gabriš, Andrej ; Jopek, Miroslav (referee) ; Zouhar, Jan (advisor)
This diploma thesis deals with the analysis of machining of aluminum alloy with the designation EN AW-6061 T6511 according to ČSN EN 573-3. The first part of the thesis provides a theoretical introduction to the measurement of cutting forces with application of different approaches. The thesis further analyzes the topic of quasi-static and dynamic material behavior and its description by Johnson-Cook plasticity material model. The last part deals with parsing of mathematical approaches in finite element method (FEM) and the simulation of machining under the chosen cutting conditions.
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Production of the distributor by non-convential forming technology
Blažek, Matěj ; Peterková, Eva (referee) ; Jopek, Miroslav (advisor)
The thesis is focused on the evaluation of the possibility of manufacturing a distributor body used for distribution of heat-bearing medium in underfloor heating. For the part, due to the series of 100 000 pieces·year-1, the technology of high-pressure hydrofroming without active action of axial presses is chosen. The original solution with a forming pressure of 58,5 MPa did not lead to success and an optimization was necessary, where the pressure was increased to 158,5 MPa, which also did not lead to success. This was followed by a further optimization consisting of hot forming at 700 °C and a pressure of 158,5 MPa, again with no successful solution. The last possible treatment option of changing the material to 11 321 steel and pressure 134,2 MPa was not successful and the high pressure hydrofroming method with passive action of axial dies is not recommended for industrial practice. The final step was an economic evaluation, where the price per piece was determined to be 133,3 CZK with a 20% margin. Considering that the product is suitable the profit will start to be generated after the production of 140 460 pieces.
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Optimisation of punch tool for produce holes of bearing cage
Matail, Petr ; Jopek, Miroslav (referee) ; Peterková, Eva (advisor)
The thesis is focused on analysis of causes of blanking punch cracking, which is used for piercing holes of barrel bearing cages and designing of new construction solution by changing shape of blanking punch. Multiple variants of rounding shearing edge and chamfering shearing edge was designed. The current state and designed variants were analysed by simulation in Simufact Forming program. The variants were compared by shear force progress, equivalent stress, contact pressure in blanking punch and effective plastic strain in blank cage. According to mentioned criteria the best solutin with rounding shearing edge by 0,7 mm and chamfering face of blanking punch by 10° was chosen.
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Production concept of sink
Bahula, Jan ; Jopek, Miroslav (referee) ; Císařová, Michaela (advisor)
The thesis presents a design for manufacturing a rotary kitchen sink made of a stainless austenitic steel 17 240 with a thickness of 0.8 mm with a production series of 20 000 pieces per year. Based on the analysis of manufacturing variants and necessary calculations, deep drawing without a reduction in the thickness was selected to three operations including calibration. A hydraulic press PO 250 from Dieffenbacher was chosen based on the required forces and available rams. The drawing process was checked using numerical simulations and tools were designed for each operation using a drawing ram, a bottom blank holder, and an upper ejector. In the design of drawing tools, normalised components or easily manufacturable parts were preferred.
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Manufacturing of a Hand Dryer Cover
Štancl, Oldřich ; Jopek, Miroslav (referee) ; Řiháček, Jan (advisor)
The thesis deals with the design of the hand dryer cover made of stainless steel X5CrNi18-10. The manufactured part has a hollow rectangular shape with a rounded bottom and a constant wall thickness of 1 mm. Due to the simplicity of the shape, material properties and the annual production series of 200,000 pieces, deep drawing technology is chosen for production. The part is produced in one drawing operation, for which the necessary technological and control calculations are performed. Using the calculated parameters, a DIEFFENBACHER PO 250 hydraulic three-acting press is selected. A simple drawing tool is constructed for the machine, whose operation and manufacturability of the cover is subsequently verified using numerical simulation in the PAM-Stamp software.
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Manufacturing of kitchen sink
Vágner, Lukáš ; Peterková, Eva (referee) ; Jopek, Miroslav (advisor)
The project deals with the design of production of the kitchen sink made of chromium-nickel austenitic steel 1.4301. Material thickness of the sink is 1 mm. The annual production series is 30,000 pieces. After considering the size of the produced series, a combination of shearing and deep drawing was chosen as the production technology. Shearing of the circular shape was combined with the execution of both draws into one production tool. For this design, the necessary calculations were performed along with verification by simulations in the PAM-STAMP program.The tool is clamped in a hydraulic press PO 400, which has all the necessary parameters. The coil blank is guided through the unwinding and straightening device Compact Line GLK3-1000. The selling price of one sink was set at CZK 1,300. Production becomes profitable after producing 7540 sinks.
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