This is the first hot strip mill at JSOL's Angul site in Odisha, and it marks another chapter in the long partnership between Jindal Steel and SMS group. They've worked together on several projects before, so Jindal Steel trusted SMS group to build this 1,780-millimeter HSM with cutting-edge technology for producing thin hot strips.
The mill is packed with advanced equipment. It includes a primary descaler, two roughing stands with edgers, a cooling system, heat preservation hoods, a coilbox without a mandrel, edge heaters, a drum shear, a secondary descaler, a seven-stand finishing mill, laminar cooling, and three downcoilers. Plus, the mill features AMOVA coil handling system, strapping machines, marking machine, and inspection line.
Groundbreaking technology for challenging products
The mill can handle a wide range of steel grades, including high-strength low-alloy (HSLA), pipe grades, and silicon steels. Over 20% of the materials are tough grades, and the mill can roll very thin strips reliably thanks to innovative rolling technologies. Some of the standout technologies include:
- Transfer bar cooling: For optimal temperature regulation in the roughing mill, SMS group installed the newly developed transfer bar cooling system. The transfer bar cooling prevents uncontrolled air-cooling during oscillation and comes with favorable effects on temperature profiles. The effects on the rolling process in the finishing mill are positive. By equalizing the temperature, product homogeneity is improved.
- HIBOX® heat preservation hoods: JSOL’s HSM is equipped with the latest generation heat panels of the HIBOX® type. This simplifies the inspection and maintenance of the elements and increases the service life by factor four compared to conventional preservation hoods. Using the HIBOX® heat panels makes the finishing train’s rolling behavior more stable and JSOL is able to shift the product mix toward smaller final thicknesses and/or higher strength steel grades. The HIBOX® system comes with resilient savings in terms of energy, CO2 footprint and OPEX.
- Mandrel-less coilbox: Arranged between the second roughing stand and the finishing mill, the coilbox forms transfer bar into coils and thereby equalizes the temperature over the transfer bar length. Coiling the transfer bar prevents the inner windings from cooling. Material and heat are accumulated, providing a positive effect on the material to be rolled and the production process. The improved transfer bar temperature allows expansion of the product range to thinner gauges.
- Edge heater: Located upstream of the finishing mill descaler, the edge heater utilizes inductive heating. The primary role is to enhance strip edge quality by maintaining optimal pre-rolling temperatures. This ensures flawless production, even for advanced grades.
- Finishing mill: The seven-stand finishing mill in 4-hi design is equipped with hydraulic adjustment systems, hydraulic loopers and latest generation CVC® plus (Continuously Variable Crown) combined work roll shifting and bending systems. Also part of the supply was the X-Pact® Profile, Contour and Flatness process model (PCFC) being able to cope all requirements in terms of producing high sophisticated products with an exceptional wide range of properties and dimensions. PCFC calculates the optimal set points for the actuators of the CVC® plus and bending system. This is why PCFC ensures the stability of the rolling process, highest product quality regarding strip geometry and a flexible rolling schedule.
The high-capacity hot strip mill is completed by the laminar cooling system and three downcoilers as well as AMOVA coil conveying system, strapping machines, marking machine, and inspection line.
