- New continuous caster No.5 produces ultra‑thick slabs up to 460 millimeters thick and 2,700 millimeters wide
- Marks the fifth slab casting project between Baosteel Zhanjiang and Primetals Technologies
Baosteel Zhanjiang Iron and Steel has successfully commissioned its new two-strand ultra-thick slab caster from Primetals Technologies—Caster No. 5—at the Zhanjiang plant in Guangdong Province, as of January 9, 2026.
Designed to accommodate record-setting ultra-thick slabs up to 2,700 millimeters wide and 460 millimeters thick, the new caster features advanced engineering. Its Single Roll DynaGap (SRD) segments, with a load capacity of 5,000 kilonewtons per roll, allow for significant thickness reduction during casting. This technology ensures superior internal slab quality and enables the reliable production of high-quality, defect-free ultra-thick plates.
Cost-Effective and Efficient Production
With an annual capacity of up to 3.5 million tons, Caster No. 5 produces steel for offshore applications, wind power, shipbuilding, and more. Compared to conventional ingot or vertical casters—typically used for slabs of this thickness—the new bow-type continuous caster offers considerably higher cost-effectiveness and efficiency.
Primetals Technologies delivered a complete solution, including engineering, supply of main mechanical and electrical equipment, Level 1 and Level 2 automation systems, and advanced digital solutions for the caster.
A standout feature is a breakthrough software solution that determines the ideal roll geometry to prevent mold-level hunting—intense mold-level fluctuations—already at the design stage. This reduces fluctuations caused by unsteady bulging by 50 percent, resulting in higher casting speeds and increased productivity. The software optimizes roll geometry by considering multiple parameters, such as steel grades, section sizes, and casting speeds, to define the optimal arrangement.
Long-Term Partnership Delivers Five Casters
Over the years, Baosteel Zhanjiang and Primetals Technologies have developed a strong and successful partnership. Primetals Technologies has supplied the design and equipment for five slab casters at the Zhanjiang plant. Casters No.1, 2, 3 and 6—delivered previously—have operated reliably and efficiently since commissioning, consistently achieving industry-leading performance.
Baosteel, part of China Baowu Steel Group Corporation—one of the Fortune Global 500 companies—operates integrated iron and steel plants at several sites, including Shanghai, Wuhan, Nanjing, and Zhanjiang.
Key Facts: Baosteel Zhanjiang’s 2‑Strand Ultra‑Thick Slab Caster
Capacity: 3.5 million tons per year
Radius: 12 meters
Metallurgical length: 44 meters
Dimension of slabs: 300 to 460 millimeters thick and 1,600 to 2,700 millimeters wide
Steel grades: Medium‑carbon, high‑carbon, peritectic, high-strength low-alloyed (HSLA), pipeline steels, and more
Baosteel’s new ultra-thick slab caster from Primetals Technologies can produce slabs up to 460 millimeters thick.
The caster features a breakthrough software solution from Primetals Technologies that determines the ideal roll geometry at the design stage.
The Primetals Technologies project team after the successful commissioning of Baosteel’s new caster No.5.
Primetals Technologies, Limited, headquartered in London, United Kingdom, is a pioneer and world leader in the fields of engineering, plant building, and the provision of lifecycle services for the metals industry. The company offers a complete technology, product, and services portfolio that includes integrated electrics and automation, digitalization, and environmental solutions. This covers every step of the iron and steel production chain—from the raw materials to the finished product—and includes the latest rolling solutions for the nonferrous metals sector. Primetals Technologies is a Group Company of Mitsubishi Heavy Industries, with around 7,000 employees worldwide. To learn more about Primetals Technologies, visit the company website www.primetals.com.
