On January 24, 2025, thyssenkrupp Steel reached another milestone in the modernization of its Bochum site: The new annealing and insulating line was successfully put into operation. This ultra-modern, energy-efficient line largely completes the comprehensive modernization of the Bochum plant. The line enables the production of electrical sheets with a thickness of up to 0.2 mm, which impress with their homogeneous mechanical and magnetic properties. These sheets have been specially developed for use in highly efficient motors, such as those required in electric vehicles in particular.
A double reversing stand using the latest technology, which is located upstream of the annealing and insulating line, had already been completed. The modern production setup is complemented by an electrical steel strip inspection line and a finishing line that cuts the finished sheets and assembles them for customers. The finishing line, which is scheduled to be commissioned in 2026, will further strengthen the site.
Investing in the future: Bochum site as a center of excellence
Dennis Grimm, CEO of thyssenkrupp Steel, explained: “With the commissioning of the annealing and insulating line, we are taking an important step towards the future: Our aim is to be the technology and quality leader, especially in demanding premium steels. We have invested around 300 million euros in our site in Bochum in order to strengthen and expand our position in steels for electromobility and high-strength multiphase steels. In conjunction with the major investments at the Duisburg site, we are now on the home straight in the implementation of the investments from Strategy 20-30. The core of the strategy remains the right one, even under changed market conditions: the consistent optimization of our production network and our product portfolio for future markets and the increasing requirements of our customers.”
The new annealing and insulating line can produce over 200,000 tons of non-grain-oriented electrical steel per year. The plant was realized together with the Düsseldorf-based SMS group. The modernization will gradually transform the production facility on Essener Strasse into a center of excellence for electromobility and high-strength materials. Following the completion of the double reversing stand, the construction of the annealing and insulating line marks a decisive step in this transformation.
Technological advances for electromobility
The high-quality, extremely thin steels that can now be produced in Bochum are tailored to the growing requirements of electromobility. With their high silicon content, they contribute to improving the energy efficiency of electric motors, which increases the range of electric vehicles, for example. In the new plant, the structure of the cold-rolled strip is recrystallized during the annealing process and then textured. Finally, the material is coated with an insulating layer to increase the efficiency of motors and generators and minimize magnetization losses.
Sustainable further development and long-term prospects
The modernization of the Bochum site is a central component of the market-oriented optimization strategy thyssenkrupp Steel has been pursuing since 2020. The focus is on the development of high-tech steels for electromobility and higher-strength multiphase steels. The production of electrical steel for electric motors and generators, which currently still takes place at the plant on Castroper Strasse, will be gradually transferred to the new high-tech units on Essener Strasse once the finishing shop has been commissioned.
Dennis Grimm emphasizes: “Focusing, increasing our competitiveness and concentrating on the needs of our customers are the driving forces behind our realignment. The Bochum site plays a central role in this. We want to bundle our expertise here, thus future-proofing the site and retaining as many good jobs as possible in the long term. We have now created the essential prerequisites for this.”
Key data for the annealing and insulation line:
- Investment volume: approx. 150 million euros
- Capacity: approx. 218,000 t/a (portfolio-dependent)
- Strip widths: 700 mm to 1,350 mm
- Belt thickness: 0.2 mm to 1.0 mm
- Material used: 35,000 m³ excavation/63,000 t; approx. 20,000 m³ concrete/46,000 t; approx. 2,700 t reinforcement
With this comprehensive modernization, thyssenkrupp Steel is setting the course for a sustainable future for the Bochum site and underlining its leading role in the development of innovative solutions for electromobility.
Source: thyssenkrupp Steel Bochum
