|
|
Bulk forming technology of connecting pin
Koukal, Vojtěch ; Šlais, Miroslav (referee) ; Forejt, Milan (advisor)
The project of master’s thesis elaborated within engineering studies of engineering technology deals with concept of manufacturing procedure of connecting pin made of steel 11 320 5R with cold forming. Two variants of production technique were projected based on the literature study of the cold heading and cold extrusion. Selected variant, for which the technological calculation was accomplished, consists of five forming operations. Manufacture was projected for multistage automatic forming machine TPM 8-A made by manufacturer Šmeral Brno with nominal forming force 1000 kN. Tool steel 19 436 was chosen as a material of extrusion and heading tools.
|
|
|
Computational prediction of material damage in forming
Kunc, Vítězslav ; Hůlka, Jiří (referee) ; Petruška, Jindřich (advisor)
The purpose of this thesis is to deal with the initiation of chevron cracks in forward extrusion. Using numerical simulation, the ability of selected fracture models which prognosticates the initiation of chevron cracks is observed. The influence of process parameters is studied (friction, reductions in cross section and angles of reduction) on the initiation and diffusion of damage. Solutions was executed by Abaqus for material 12 050.
|
|
|
Influence of process parameters in forward extrusion on the die loading
Pokorná, Jana ; Návrat, Tomáš (referee) ; Petruška, Jindřich (advisor)
One of the decisive factors of effective using of forward extrusion technology is lifetime of forming tools. Die is very loaded forming tool which loading and therewith related lifetime can be significantly affected by its construction. Construction also affected quality of extruded material. Finete element method allows to simulate this process and assess force which is needed to extrusion and state of stress in die and extruded material. Numerical simulation was realized in program ANSYS 11.0. Influence of reduction, angle of reduction, lenght of extruded material, rounding transition of die parts, extruded material and friction coefficient on die loading and emergence of cracks in extruded material was set in this diploma thesis. Results can be used to die construction optimalization.
|
|
|
Implementation, Calibration and Application of Ductile Fracture Conditions in FEM Programs
Kubík, Petr ; Plánička, František (referee) ; Kotoul, Michal (referee) ; Petruška, Jindřich (advisor)
The presented work is concerning with ductile fracture problematic under monotonic loading which is result of gradual material degradation at large plastic deformation. At present, a large number of models, which calibration is not trivial, are used for its prediction. Ductile fracture mechanisms and cut-off region are described in the literature search part. Next, there is given a summary of criteria which are based on different approaches to ductile fracture. There were proposed and used KHPS and KHPS2 criteria within this PhD thesis. Procedure of assessment of the stress-strain curve and ductile fracture criteria calibration are described in last part of the literature search. A summary of tests, which were done in order to calibrate chosen criteria, is given in experimental part. Various stress states within broad range of stress triaxiality and Lode parameter were reached using these tests. Special type of specimen, by which very low stress triaxiality value is reached, was designed within this work. All specimens were made from the steel 12 050. Wrought rods of one melt with circular cross-section of 27 mm in diameter were used as semi-product. Calibration of chosen ductile fracture criteria was performed using foregoing tests. These criteria were implemented by author into explicit finite element software ABAQUS/Explicit using user subroutine VUMAT. Chosen criteria were used for simulation of multistep extrusion at which formation of internal central cracks occurs. These criteria were also used for simulation of cutting of circular cross-section rods. Results from simulation were compared to experiments which were done by industrial partner J-VST.
|
|
|
Production of pressure filter casing
Janoušek, Jiří ; Forejt, Milan (referee) ; Podaný, Kamil (advisor)
The project presents a proposal for the technology of production of the pressure filter casing used in hydraulic systems, which is made of non-alloy carbon steel 12 020. With the help of a literature study of cold extrusion and calculations, the production of the component was designed, which will take place in two operations. Before each operation, the surface treatment is performed by phosphating and soaping and inter-operational annealing must take place. Tool sets were designed for both operations and a press was selected from the company's machine park with a nominal force of 25,000 kN. Finally, a technical and economic evaluation was proved, which shows that the price of production of one piece is CZK 187. The turning point was set at 3 497 pieces per year.
|
|
|
Production of a hollow pin by cold forming
Šanca, Kristián ; Řiháček, Jan (referee) ; Jopek, Miroslav (advisor)
The hollow pin with a length of 45 mm and a diameter of 28 mm made of 12 050 steel is produced by cold cold forming. It showed defect-translation and the goal was to eliminate it by optimization. 10 variants were proposed, of which No. 10 was without defects and the goal of the work was met. The forming process was simulated by Simufact Forming software. The semi-finished product is a block made of a round bar 18 x 35.68. The part is manufactured on a process tool for 4 operations by a combination of upsetting and extrusion. The machine used is the CBF-204L automatic machine. The required force is 3 042 kN. The price of 1 piece is CZK 19.59. 120,000 pieces are produced annually.
|
|
| |
|
|
Design of Coupling Pin Production
Blažek, Matěj ; Podaný, Kamil (referee) ; Řiháček, Jan (advisor)
Bachelor’s thesis is aimed production of pin, made from steel 11 320-5R. This piece is in accordance to serial production 500 000 pieces year -1 made by cold bulk forming. Specifically it is about heading and forward extrusion. From two production variant was chosen the one with lower strain. By calculations there was set the power needed for production that equals Fc= 368,5 kN. Because of this power there was chosen a machine AKP 3-5 from company Hatebur. In the next step there was designed method that is in the attachment to the thesis. Final step was a control whether the idea of production by simulation is correct or not.
|
|
|
Production of splined sleeve
Vališ, Ondřej ; Lidmila, Zdeněk (referee) ; Císařová, Michaela (advisor)
The master’s thesis submits a technological project of production of splined sleeve used in automotive as a component of propeller shaft. The part is made of steel ČSN 11 523 by bulk forming technology in an annual production series of 20 000 pieces. Production process was designed in four operations, after the second operation there was recrystallization annealing included for regeneration of plasticity before following extrusion. There were made technological calculations for these production operations. Operations were projected to be done by common one-operation press machines available in local manufacturing facility. For all the operations were designed functional tools and tools setups. In conclusion, there was performed technical-economic evaluation. As emerged from this evaluation the final amount of total production costs for one piece is 131,- Kč. When 9 393 pieces are produced, the production series reaches to the break-even point and then the profit starts to be generated.
|
|
|
Production of spring buch by cold forming
Kosek, Lukáš ; Dohnal, Ivo (referee) ; Forejt, Milan (advisor)
The master’s thesis presents a concept for spring bush manufacturing made of 11 320-5R steel by cold forming. Five steps process of manufacturing is based on the literary studies and technical calculations. The multistage cold forming machine HATEBUR AKP 5-5 was chosen for selected option of forming technology. As raw material was used cylinder shape with diameter of 26 mm and length of 29 mm. The economic results fix the price of one component of 16 CZK for annual dose 250 000 pieces.
|
guest ::
