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The paper deals with the software DEFORM, which is used for forming simulations at the Regional Technological Institute in University of West Bohemia in Pilsen, and with the issue of acquisition and validation of material data. Material library is an essential part of a software, but sometimes it is necessary to add individual material into the library or edit existing materials to improve their description. The article describes the real material tests and individual parameters that should be considered during material description. Further is shown data conversion for virtual simulations in DEFORM software. At the end, the verification of material description is shown. It is done by the comparing of results given by virtual simulation and by the real forming process. The whole procedure of new material description is shown on the brass CuZn30. Material description is deeply described in this paper.

This article explores the influence of production technique on the strength of nylon parts. Identical specimens were manufactured by various techniques. The material of specimens was nylon PA6. 3D printing and injection molding were used, with various orientations of printed layers, and various orientations of specimens in the working space of the 3D printer. The variants are described in detail. A special mold was used for the injection molding process in order to make specimens with and without a weld line. The effect of this weld line was evaluated. All specimens were tested using the standard tensile test configuration. The strength was compared. It was found that the same plastic material has very different mechanical properties depending on the production process.

Dynamic behavior of the forging machines is necessary to explore due to the increasing of speeds on large forging hydraulic presses for open die forging. The paper describes the modal analysis of two selected presses, which represent the most common designs of hydraulic presses for forging. The first press is with double-column frame CKV 50 with the force 50MN and the second one is with four-column frame CKV 170 with the force 170 MN. Further are described the simulations of oscillation, which was excited by time-dependent work force. Results of analysis are compared with measurement in the real operation.

This paper deals with the possibilities of advanced FEM simulations used for the understanding of process of loading of crank presses. Concrete example presents transient (time-dependent) dynamic simulation loading. Load input parameters of forging press are determined from simulation of technological operation of forming. Results of virtual simulations are compared with standard analytical calculations.