The hot strip mill is scheduled for commissioning in early 2019 in Cilegon on the Indonesian island of Java. This is where PT Krakatau Steel (PTKS) operates an integrated steel plant for which SMS group had supplied a hot strip mill, among other equipment, in the 1980s.
The new hot strip mill for strips with a maximum width of 1,650 mm will have a capacity of 1.5 million t/a in its first expansion stage. Key components are a reheating furnace, a four-high reversing roughing stand with edger, the six-stand finishing mill, a laminar strip cooling section, a universal coiler and the coil transfer system. At a later stage, the annual production can be increased to up to 4 million t/a.
The hot strip mill is equipped with numerous technology packages and Ecoplants components required for the economic manufacture of high-quality hot strip. Thanks to the utilization of low-emission burners, the walking beam furnace achieves low pollutant values, which are monitored constantly via an online system. The four-high reversing roughing stand operates with the technology for camber-free rolling, which enables the avoidance of strip camber due to temperature or thickness rundowns. The temperature losses in the transfer bar are reduced by newly developed and highly efficient heat retention hoods between the roughing stand and the crop shear.
The finishing stands are equipped with the CVC plus system (Continuously Variable Crown) with integrated work roll bending and hydraulic roll-gap adjustment systems, enabling strips to be produced with very close thickness, profile, contour and flatness tolerances. The Ecoplants components in the finishing mill include the Sieflex HT high-performance spindles, the design of which allows the trans­mission of higher rolling torques with smaller work roll diameters. A further innovation is a highly efficient two-stage work-roll cooling system, operating with various pressure stages.
SMS supplies the entire plant automation, the drive technology and the electrical power distribution. On Level 0, this equipment comprises the sensor technology, the technological measuring devices, the main and auxiliary drives, as well as switchgear units and compensation equipment. The Level 1 automation systems are designed completely on the basis of the most up-to-date embedded technology, involving an efficient and, at the same time, lean hardware design.
The innovative operating concept X-Pact vision is designed according to state-of-the-art ergonomic knowledge and enables the operator to act intuitively to achieve optimum process control. The Level 2 process automation contains the technological process models, ranging from the pass schedule calculation PSC (Pass Schedule Calculation) via the profile, contour and flatness model PCFC (Profile Contour Flatness Control) up to the cooling section model CSC (Cooling Section Control) and temperature control. Likewise, SMS supplies a microstructure model MPM (Material Property Model), which determines the mechanical properties of the products and supports and simplifies the introduction of new materials.
Within the framework of Industry 4.0, a powerful PQA (Product Quality Analyzer) system will continuously monitor all process and product quality parameters. The new hot rolling mill will be one of the most modern facilities of this type worldwide, enabling PTKS to fulfill highest demands regarding quality, productivity, and production cost.
_{(Source: SMS group)}