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Abstract: In FEA of ring rolling processes the tools’ motions usually are defined prior to simulation. This procedure neglects the closed-loop control, which is used in industrial processes to control up to eight degrees of freedom (rotations, feed rates, guide rolls) in real time, taking into account the machine''s performance limits as well as the process evolution. In order to close this gap in the new simulation approach all motions of the tools are controlled according to sensor values which are calculated within the FE simulation. This procedure leads to more realistic simulation results in comparison to the machine behaviour. [Copyright &y& Elsevier]

Abstract: One of the most important target parameters during open die forging is the microstructure, respectively the grain size. To guarantee the mechanical properties within the workpiece it is of high interest to predict the microstructure during the forging process. This paper details different semi-empiric models that ultimately help to predict the microstructure properties of a forged block. The results of the fast models show a good match with the slower FEA reference solution. The vision is, to use the developed models in an assistant system which suggests the optimal forging continuation and thus helps to optimize the forging process online. [Copyright &y& Elsevier]

Abstract: Grid sheet is a sandwich material consisting of two metal face sheets and a core of woven wire mesh that are joined by welding. It has been designed to act as an actively cooled heat shield, e.g. for steam turbine casings. For this purpose, cylindrical parts have to be produced from initially flat grid sheet. This paper focuses on four-roll bending of grid sheet. It is shown that springback and the number of failed spot welds after forming can be reduced by stress relief annealing and appropriate forming conditions. A finite element model of roll bending of grid sheet is presented, which has been set up to predict springback and spot weld failure. [Copyright &y& Elsevier]

Abstract: The demand for the simulation of incremental bulk forming processes is high. However, the computation times for such simulations are still unsatisfactorily long and thus, their application is deterred. To accelerate the simulations, a multi-mesh algorithm was implemented in the Finite-Element simulation package PEP&LARSTRAN/Shape. This method uses a FE mesh which is fine in the deformation zone and coarse in the remaining areas. A second mesh, fine over the entire volume, is used to store computed values and to minimize the loss of accuracy. The method was tested on an open die forging process and adapted for ring rolling. This paper describes the latest further developments of the method in [1], for instance tool kinematics, remeshing and data transfer and compares its results to conventional models, thereby showing its performance and accuracy. [Copyright &y& Elsevier]