In a class of its own
Scientists from the FAU use globally unique stamping press
Weighing in at 100 tons and measuring more than nine meters in height, but accurate down to one hundredth of a millimetre: the Neue Materialien Fürth GmbH (NMF) stamping press is a true heavyweight. This piece of research machinery is one of a kind in Europe thanks to the numerous functions it masters: forming, pressing and compressing a wide variety of sheet metals of varying thickness. This enables cooperating scientists and engineers from the department of Manufacturing Technology and NMF GmbH to manufacture materials and structural components with completely new properties, which can then be just as easily applied to the automotive industry, as to aerospace technology or, indeed any other industry sector involved in sheet metal processing.
The core component of the press is the cuboid ram which, alone, weighs in excess of 24 tons. It has a base area of four square metres, is over two metres in height, is held in place using laterally mounted guides and can move at speeds of up to 0.25 metres per second. By contrast, conventional stamping presses generally only move at speeds of up to 0.04 metres per second. To put the potential speed of this 24-ton-weight into context, a 100 metre sprinter would run at a snail’s pace by comparison.
A 2.5 square metre press bed constitutes the lower part of the press. Sheet metal inserted into the working area of the press can be formed with specifically designed moulds. Here, the sheet metal which is to be shaped (e.g. a flat circular sheet) is positioned between two complementary masters; the moulds. To provide a straightforward example, a dish-like mould is placed under the sheet of metal before the negative of this is stamped into the sheet metal by the impact of the ram. With sufficient force the material is permanently reshaped to make a sheet metal dish, the same shape as the template below. During such processes the press exerts infinitely variable power of up to 4,000 kilonewtons, equivalent to a mass of 400 tons or 400,000 kilograms.
The press’ “wobble function” makes it the only one of its kind in the world and demonstrates what the machine is capable of – not only performing simple, linear movements up and down, but also lifting and lowering the lower mould while rotating and thereby allowing the mould to be tilted. This makes Fürth home to the only press in the world to use a hip swing technique, and as such it has no reason to fear comparison with human competition. The Fürth hydraulic press uses a special technique to achieve the “wobble effect” and to date there is no comparable equivalent in the world. With minimum effort, scientists can place a seven-ton-heavy plate, known as a “wobble module”, which can be tilted and swivelled on the press bed. At the corners of this plate there are cylinders which can be extended to different lengths. As such, the plate can be tilted to infinitely adjustable angles during the process. Because the localised force of the ram is distributed unevenly on the sheet ready for pressing, the sheet is, in turn, given its own unique shape. The introduction of the wobble plate not only affords researchers tremendous flexibility as regards the manufacture of their structural components and semi-finished products, but more importantly it facilitates unparalleled precision.
For more information for the media:
Prof. Dr. Marion Merklein
uni | media service | research No. 51/2011 on 13.10.2011