Shanxi Taigang Stainless Steel Co. Ltd. (Tisco), a steel producer based in Taiyuan, the capital of the Chinese province of Shanxi, has successfully commissioned a 4.3-meter heavy plate mill from the SMS group. The plant is the most powerful of its kind that SMS has ever supplied. The mill exemplifies high environmental compatibility and innovative technology. It has a rolling force of 109 MN with a bale length of 4.3 meters. The mill can also roll a wide range of materials, including carbon steels, quality steels, low-alloy steels and steels for shipbuilding, bridge building and pressure vessel construction. Tube grades in line with API standards, stainless steels, and nickel-base materials can also be produced.
New Rolling Mill
The new rolling mill, consisting of a four-high stand and an edging stand, is the heart of the new plant. The vertical edger is equipped with a combined mechanical/hydraulic roll adjustment system for even the tightest width tolerances. Thanks to a carrying roller table equipped with a newly developed drive, the heavy edging stand can also process very short slabs.
Features of the four-high stand are a high rolling force and high forming capacity. The combination of the coaxial CVC®plus (Continuously Variable Crown) system and a very large roll gap opening is another new development enabling Tisco to process rolled stock with an input thickness of 960 millimeters. This way, Tisco can expand its product range.
The mill is characterized by a high degree of rigidity, achieved through special design features, such as back-up rolls with a diameter of 2.3 meters. In addition, the plant is easy to maintain.
Expanded Product Range
The new plant enables Tisco to roll out very large cast ingots as well as small-dimension slabs. Dynamic and flexible production is thus made possible, while the tightest geometric tolerances can be maintained at the same time.
The plate mill can produce sheets in widths of between 1,550 and 4,200 millimeters and thicknesses of 5 to 120 millimeters. Its annual capacity is 700,000 tons. In the future, it will be possible to roll even thicker sheets. Further, the new rolling line will enable Tisco to expand its product range. The company particularly appreciates the possibility of being able to manufacture products for the chemical industry, the infrastructure sector, shipbuilding, or for onshore and offshore wind turbines made of modern materials such as duplex steels, stainless steels, nickel-base alloys, and superaustenitic grades.
Fully Automatic Control
The fully automatic control of the rolling process is handled by the SMS group's X-Pact® automation system, ensuring high plant efficiency. Thanks to the precise planning and close cooperation between SMS and Tisco, as well as the extensive use of the X-Pact® Plug & Work integration tests, the first plate could be rolled just one and a half months after the I/O check, which reduced the originally planned commissioning time by two weeks.
Level 1 automation is carried out entirely with X-Pact® technology. To enable intuitive operation for optimal process control, the X-Pact® Vision operating concept was developed with the latest ergonomic findings in mind. Level 2 process automation includes the profile and flatness model X-Pact® PFC® (Profile and Flatness Control), the technological process models X-Pact® PSC® (Pass Schedule Calculation), and the overriding material tracking system.
"We are very proud that our international team was able to complete this project successfully despite the mobility and travel restrictions imposed by the covid-19 pandemic, which made it very difficult to visit the site. Our modern digital conferencing and communication facilities have fully proven their worth here, and they will continue to support us until the final approval," says Michael Bohland, project manager on the part of the SMS group.