Bloom Caster CC4 at voestalpine Stahl Donawitz, Austria

The initial idea to build the new CC4 as a replacement for the CC2 (startup 1980) at voestalpine Stahl Donawitz GmbH came in the third quarter of 2014. Before the involvement of Primetals Technologies in the second quarter of 2017, plenty of various planning efforts had already taken place. Due to the tight space situation in the existing casting bay, an alternative erection place for the CC4 had to be found. The identification of the new erection area enabled the machine to also have a future provision for a 5th strand, as well as the possibility to cast bigger section sizes.

The successful realization of the CC4 project was anchored in advanced digitalization, with a focus on Through-Process Quality Control (TPQC). This system integrates data collection across all production stages, ensuring consistent high-quality output. The TPQC system is pivotal for adhering to stringent automotive standards like the IATF 16949:2016. The Level 2 models, including Dynacs 3D and DynaGap, dynamically control and optimize the casting process, ensuring precise bloom solidification and surface quality. Additionally, the CC4 features a fully automatic crane system that efficiently manages bloom handling and storage, enhancing operational efficiency and product quality. These technological advancements have enabled voestalpine Stahl Donawitz to produce blooms with exceptional internal and surface quality, free from defects.

Since its commissioning, the bloom casting machine CC4 has consistently delivered outstanding results, aligning with the highest quality standards in steel production. The implementation of advanced digital models such as Dynacs 3D and DynaGap has led to precise control over the casting process, resulting in blooms with exceptional internal and surface quality. The innovative electromagnetic stirring and soft reduction techniques have minimized carbon segregation, achieving segregation index values as low as 1.01 to 1.05 for the 330x440 mm² section in steel grade 100Cr6. Moreover, the automated systems have ensured that the production process remains efficient and reliable, with no internal or surface cracks reported. The enhanced macroscopic cleanliness of the blooms has significantly reduced rejection rates, particularly in rail production, underscoring the effectiveness of the digital quality control and process optimization strategies employed at the plant.