At the beginning of April, Siemens Metals Technologies received the final acceptance certificate for the stainless steel works owned by Outokumpu Stainless in the USA. The plant was constructed in Calvert, Alabama, and went into operation in November 2012. The scope of supply from Siemens included an electric arc furnace, an AOD converter, secondary metallurgical facilities, and a continuous slab caster. The plant is designed to produce one million tons of AISI 200, 300 and 400 grades of stainless steel per annum.
The new stainless steel works was constructed on a "green field" site near the port of Mobile for ThyssenKrupp Stainless LLC, and sold to Outokumpu at the end of 2012. Siemens received the order to equip the plant in 2008. Liquid steel is produced in an electric arc furnace with a tapping weight of 160 tons. The steel is then further processed in a 180-ton AOD converter and a ladle treatment station. Integrated basic automation and a Level 2 process optimization system ensure that all components of the plant interact optimally. In order to minimize the environmental impact, Siemens installed a dedusting system with pulse-jet filters for the electric arc furnace and the AOD converter.
Siemens supplied the complete, single-strand continuous slab caster for the casting section. The bow-type caster has a casting radius of 9 meters and a straight mold. It is designed to produce slabs ranging in width from 800 to 1900 millimeters and thicknesses from 180 to 240 millimeters. The casting speed is 1.3 meters per minute. The plant produces stainless steels of AISI quality grades 200, 300 and 400 for a wide range of applications. The casting plant features a number of technology packages to assure the internal and external quality of the slabs. These include a mold level control, a breakout detection system, a hydraulic mold oscillator and a system to adjust the width of the slabs. The strand containment is equipped with smart segments. The combination of the Dynacs cooling system with internally cooled I-Star rollers offers maximum flexibility in the secondary cooling. The scope of supply also includes the complete basic and process automation, as well as machines for weighing the slabs.
Siemens was responsible for engineering and supplying the equipment, supervising the installation and commissioning work, and providing the training of the customer’s personnel.