Krefeld, November 2009

Siempelkamp was commissioned by Alcoa Forgings &Extrusions business to engineer and produce the cast parts of one of the world’s largest closed-die forging presses located in in Cleveland, Ohio, USA. Siempelkamp was contracted by Alcoa to help rebuild and modernize its 50,000-ton (450 MN) press to become the most advanced, productive forging press in the world. As part of the order, Siempelkamp will cast ten structural parts for the press with weights between 200 and 250 t each (220 and 270 US tons) in the company-owned foundry in Krefeld.

The 50,000 t (450 MN) closed-die forging press produces structural parts made of aluminum for the aircraft industry,. Because of its large press force and its central meaning for the American aircraft industry, the giant press has become a “National Historic Mechanical Engineering Landmark” in the United States of America.

As the world’s only manufacturer with the knowledge to design presses of this magnitude and the ability to produce castings of this size made of cast iron with nodular graphite in its own foundry, Siempelkamp received the order to produce the structural parts. In May of 2009 Siempelkamp made a casting of cast iron with nodular graphite (nodular cast iron) in its Krefeld foundry with a weight of 270 t (298 US tons) – to date the heaviest casting in the world.

The scope of supply consists of 14 large cast parts for the upper, moving and lower beams as well as the foundation stools. Ten of these castings weigh between 200 and 250 t (220 and 275 US tons).

Within the framework of the order, Siempelkamp has analyzed the design from the 1950s, carried out calculations according to the Finite-Element-Method and has optimized the construction according to the latest technology and a given maximum component part weight. The result is parts that are fatigue endurable. The special challenge for the designing engineers was that the new parts, which incorporate 50 years of technological development, had to be exactly in accordance with the old parts by eye because they simply replace the old parts.

Alcoa will carry out the installation of the cast parts on site. This means for Siempelkamp that all parts have to fit into the existing press upon arrival.

Siempelkamp casted the first foundation stool on August 20, 2009. The beams and stools are machined on large-scale machines, capable of processing components with a clamping length of 22 m (72 ft) at the Krefeld factory. The combination of engineering, casting, and machining from one source puts Siempelkamp in the position to directly influence the design, due dates, and quality of the components.

See also: http://files.asme.org/ASMEORG/Communities/History/Landmarks/5488.pdf

Image: Computer simulation of the press with a height of 30 m (98 ft)