ThyssenKrupp Steel Europe AG (Dortmund, Germany):

Blumenau M., Dr., Head of Continuous Annealing Line, marc.blumenau@thyssenkrupp.com
Norden M., Dr., Senior Engineer
Zocher U., Senior Engineer
Seynsche M., Senior Engineer
Janhofer K., Senior Engineer

The continuous annealing line of ThyssenKrupp Steel Europe in Dortmund was built in 1986. Due to the increasing demands regarding emissions, energy efficiency and materials technology, a main modernization of the line was conducted starting in 2007 with three primary issues: Modernization of the skin pass mill, of the furnace and of the automation, control and drive system. The paper presented wants to highlight the reconstruction of the continuous annealing line during a still running production with only a few short stops and gives an outlook on future proposed modernization steps. As shown, this 30-year old CAL in Dortmund became a state-of-art line with regard to the latest standards concerning safety, efficiency and materials technology. At first, the modernization was mainly focused on environmental aspects and basic automation to sustain or increase productivity of the line. But in order to enhance the capability of this line, further innovations have to be done to make the CAL ready for future market demands regarding lean advanceed high-strength steels (AHSS) concept and steel grades with ≥1000 MPa in strength. These future modernizations will concentrate on installing new process technologies such as laser welding and rapid jet cooling, for instance. The implementation of a water quench section could also be a promising option as the water quench technology allows very high cooling rates of up to 1000 ^оC/s.

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