SMS Mevac (Essen, Germany):

T. Eichert, e-mail: eichert@sms-group.com

D. Tembergen

J. Schlüter

V. Wiegmann

Big River Steel (Osceola, USA):
A. Beasly

R. Garrison

In the summer of 2014, the SMS group received an order for the construction of a new metallurgical complex for the American company Big River Steel LLC in Osceola (Arkansas). The new Flex Mill plant of Big River Steel has been marked by a choice in favor of non-standard equipment, involving the integration of an RH-degasser in the production line of a mini-plant for production of flat rolled products. The reason for this decision was the fact that the company focuses on the production of various electrical steels, including dynamo grades, that require particularly low carbon content. To achieve this result by a reliable and reproducible manner, the RH-degasser has been designed taking into account the rapid change of the vacuum chamber. The degasser operates closely with a ladle furnace and serves for the production of transformer and dynamo silicon electrical steel, used, for example, in the fabrication of rotating parts of electric motors and stationary transformers. The presented article describes the results of the hot start and production in relation to the removal of hydrogen, nitrogen and carbon, as well as the design features of the new degasser.

1. Holusha, J.: Steel mini-mills could bring boon or blood bath, The New York Times, USA, 30. May. 1995.
2. Lachmund, H.: Metallurgical measures for the achievement of ultra low carbon contents at Dillinger Hüttenwerke, Proc. Steelmaking Conf., 25–28 März 2001, Baltimore, USA, S. 613/24.