A number of technology packages will ensure that the slabs have high internal and surface quality. The order to supply a hot rolling mill to the Dolvi site has also been received by Primetals. The hot rolling mill has an annual capacity of 5 million metric t. JSW Steel already operates three continuous casting plants from Primetals at its steel works in Toranagallu, Karnataka.
JSW Steel is part of the JSW Group, and is one of India’s leading private steel producers. At its six locations in three Indian states, the company has a total installed production capacity of around 18 million metric t/a of steel. The steel works in Dolvi currently has an installed production capacity of around 5.0 million metric t/a. The new casting plants and new hot rolling mill from Primetals, together with other capital investments, will substantially increase the location's capacity. In the medium term, JSW Steel has vision to increase its total production capacity to 40 million metric t/a.
The two continuous casting plants from Primetals are designed as bow caster with straight SmartMold, and have a machine radius of 9 m and a metallurgical length of 34.5 m, with a provision of 36.9 m in future. Slabs will be cast with a thickness of 220 mm in widths ranging from 900 to 1,650 mm. The maximum casting speed will be just under 2 m/min with a provision of 2.1 m/min in future.
Primetals will install a number of technology packages to ensure not only a trouble-free casting process, but also slabs with high surface and internal quality. The packages include the Mold Expert breakout detection system, the LevCon mold level control, the DynaFlex mold oscillator, and the Quality Expert inline quality assurance system. Primetals will also supply the complete basic (level 1) and process automation (level 2) systems. DynaGap Soft Reduction in combination with Dynacs 3D cooling model will enable slabs to be cast from high-quality pipe grades and other micro-alloyed steels. Primetals will supervise installation and commissioning of the continuous casting plants, and train the customer's personnel.
The hot rolling line consists of one roughing stand with edger, a crop shear, a seven-stand finishing mill, three down coilers and a pallet conveyor. It produces hot strip with thicknesses from 1.5 to 16 mm and widths from 900 to 1,650 mm. The maximum coil weight is 34 metric t. The mill can handle many different steel grades, including carbon structural steel, high quality carbon steel, low alloy steel, DP & TRIP, as well as HSLA and API grades up to X-70.
Primetals is responsible for the design, engineering and supply of the mechanical equipment. Four stands of the finishing mill are equipped with pair cross technology. Pair cross rolls consist of upper and lower work and backup rolls set at an angle to each other, so that each pair forms an X when viewed from above. This enables the roll gap to be set optimally for fine control of the profile of the rolling stock. Depending on the angle set, the crown of the strip can be varied within wider limits as would be possible with conventional four-high stands with work roll bending. Across the world, around 150 finishing stands are equipped with pair cross technology.
Primetals will also supervise the erection and commissioning of the plant, and conduct the staff training. In addition, Primetals will supply the complete basic (level 1) and process (level 2) automation system, as well as all drives and motors for the rolling line.
(Source: Primetals Technologies, Limited)