Siempelkamp has successfully cast the upper bolster of a straightening press for heavy steel plates for Dillinger Hüttenwerke
The bolster is being machined on one of the world’s largest portal milling machines.
The casting is made of ductile graphite iron and at 270t gross is one of the largest castings. For the upper bolster of the press the company poured 270t of molten iron into a mould with a length of about 10m and a width of 3.2m in two minutes.
The project was a technological and logistical challenge. All the molten iron had to be available in five pouring ladles at the same time with exactly identical properties and the same temperature of 1350°C (2462°F).
The finished casting weight of the upper bolster amounted to 252t (278 short tons) which corresponds to the weight of nine fully loaded semi-trucks. Although large by anyone’s measure, the largest casting known to this publication weighed 350t gross and was cast by the UK’s Sheffield Forgemasters International.
The new press for Dillinger Hütte operates with a force of 65MN and will straighten high-strength sheet plates with a thickness of 300mm which can have a width between 1000 to 5200mm (3 to 17ft), a length of up to 19000mm (62ft), and a weight of up to 60t (66 st).