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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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This thesis is a summary of my research works at the MSM department of the University of Liège since 1989. These research works are devoted to the numerical simulation of the three-dimensional sheet metal forming processes by the finite element method. Several research areas, including the finite element modelling, the time-integration technique of material constitutive laws and the 3D contact treatments are covered. The theoretical methodologies, the numerical implementation and industrial applications will be presented. The thesis begins with a brief overview made in chapter 1. In chapter 2, a 8-node mixed brick element based on the HU-WASHIZU variational principle is developed (JET3D element). Special attention is paid to avoid hourglass modes as well as locking phenomena, including "shear locking" and "volumetric locking" in nonlinear analysis. Numerical examples are used at the end of this chapter to assess the performance and applicability of this element. In chapter 3, a 3D four-node shallow element, which was originally developed by Ph. JETTEUR and then has been improved by him and his co-workers, is recalled (COQJ4 element). Special care is taken to the finite rotation problems and a new formulation for the finite rotation is developed. An example is used at the end of the chapter to show the performance of the proposed formulation for the finite rotation problems. A special contact element is developed for the shell element in chapter 4. In this chapter, some basics aspects of numerical tretments of contact problem are discussed and some attentions are paid to the contact searching algorithms, which has proved to be very important in 3D cases. In chapter 5, the appropriate constitutive equations are examined together with the techniques of time-integration and the evaluation of the tangent stiffness matrix. Much attention is paid to the implicit integration methods, which have proved to be very efficient for large increments of deformation. Finally, in chapter 6, two benchmark tests are used as validation of the code. Special attention is paid to the possibility of using dynamic explicit procedure in the numerical simulation of sheet metal forming, although it is often characterised as a quasi-static process. All the developments made in the thesis have been implemented into the finite element code LAGAMINE developed since 1982 at the MSM department of the University of Liège.

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The aim of this thesis is to propose and design the production of the cap. The cap is welded to the tube of roller regal and is used for closing the tube. They together make a fixed assembly. There is a bearing molded from inside the cap and shaft passes through the center of the cap. The main function of whole assembly is to rotate the tube around its own axis. The cap will made from deep - drawing steel DC04 with a thickness of 2 mm. After consideration various possible variants for the cap production, there was chosen deep drawing without reduction of thickness as the most profitable technology. The shape of the component was modified from the technology review. There is proposed a tool that will be used for production the caps. The caps will be produced within three operations: the first two operations form a central cup and the third operation makes the final shape of the cap. Drawings for the tool are created and delivered as part of this thesis. Based on the necessary force and work calculation, it was chosen eccentric press machine S 160 E from the ŠMERAL company. With the 25 000 series, the costs of production one piece are 51,65 CZK.

The diploma thesis is elaborated within frame of masters study programme 2303T010. The work is submitting design of technology production of the drawn part – the holder. The work is based on the study of problems of the deep drawing process and related calculation was designed drawing in instrument with holder according to drawing documentation 2-5M68-12/00. The lower ejector is using for extrusion component. The drawing instrument make use of standardised components and it is solving forms of customary stool close-set on the crank drawing inclinable press LESP 63 A (producer ŠMERAL Brno, plant Trnava), with nominal tensile force 1000 kN. Drawing punch and drawing die are produced from alloyed instrumental steel 19 573, heat-worked according to drawing documentation.

The thesis solves the efficient production of the sheetmetal cover. The new technological procedure will save two manufacturing operations deep drawing. The deep drawing of the cylindrical vessel with a flange and its following calibration in accordance with the design documentation was choosed. The last stage of the deep drawing is the construcion of the circular cut-out and its bending. By doing so the final shape of the cover will be reached.

Thesis submits concept of the sink fabrication technology where circular sink is made from rustproof austenitic steel 1.4301 (X5CrNi 18-10) using technology of conventional deep drawing without reducing wall’s thickness. Hydraulic press YL32 - 400 with nominal force 400 kN has been chosen as the production machine. Drawing tool with holder was designed to be used for this technology and its drawing documentation had been enclosed in this thesis. Size of the production series was set for 20 000 products annually. Control simulation of the drawing process has proven that designed component can be made and that computations are correct. Economic and technological estimation was performed which resulted in price being set for 555 czech crowns per piece. After manufacturing first 7 447 products the manufacturing process will become economically profitable.