In this paper, a concept of a closed-loop-control system for the material flow in deep drawing processes based on a fuzzy-controller is presented. The deep drawing process is influenced by different variables as batch dependent material values, machine parameters as well as variations in the forming tools. Process stability can be improved by continuous process monitoring and process control. The control loop for controlling the material flow consists of an optical sensor, a deep drawing tool with an elastic blank holder, a fuzzy controller and a deep drawing press with a multi point drawing cushion. The controlled variable (material flow) was measured contact-free and on-line by means of an optical sensor developed at the IFUM. As control variable the different lokal blank holder forces were chosen in order to influence the material flow in different areas. In order to combine the controlled variable (material flow) and the control variable (lokal blank holder force) a fuzzy logic controller was designed. The performance of the material flow control was investigated by generating disturbances (e.g. a high blank holder force at the beginning) in the deep drawing process. This procedure shows that the fuzzy-controlled material flow can be compensated for the disturbances by means of changing the blank holder force.

The range of possible applications of ironing processes reaches from the production of cylindrical pressure tanks, shock absorber pipes, battery and beverage cans to the production of flacons for the cosmetics industry. One goal of the finite element analyses of ironing processes is to gain knowledge about process limits regarding maximized forming capacity and optimized surface quality. The ironing process is characterized by parameters like friction, geometry of the ironing ring and anisotropic material behavior. Due to the high complexity of this process, it is complicated to detect these effects on the basis of experimental investigations only. Therefore, one of the aims of this study is to identify relevant process parameters by means of systematic numerical analyses. The design of experiments was utilized to create a model of the ironing process. By means of this model it was possible to reduce the punch load and to minimize the tensile stresses in the first stage of the analyzed ironing process.