Hydromechanical Deep-Drawing of Fuel Tanks 2000-01-0415

Deep-drawing with hydraulic counter pressure presents numerous advantages compared to conventional deep-drawing. Hydromechanical deep-drawing is a capable process for producing complicated and tapered-shaped stamping parts as well as parts which require excellent surface quality, i.e. outer body panels. Due to the lower costs of dies as compared to those for conventional deep-drawing, hydromechanical deep-drawing for low volume production allows for cost-savings. By using a fuel tank consisting of an upper and a lower tray as a sample, this paper discusses the various possibilities of hydromechanical deep-drawing. The described die set has an integrated multi-point draw cushion which permits material flow control through optimized blankholder forces [Aus].

In addition, a new machine concept of a 35,000 kN press, which can be used for hydroforming of tubes, extrusions, and sheets, will be presented. The advantages of the new machine conception for sheet metal hydroforming are low investment costs for machines and tools. A 35.000 kN tube hydroforming closing device, at the Institute for Metal Forming Technology (IFU) of the University of Stuttgart, will be rebuilt according to this new concept [Bey].