March 2006 — Arcelor Group recently awarded a contract to Danieli Davy Distington to completely modernize its Slab Caster No. 1 at Sollac Méditerranée, Fos-sur-Mer.
Arcelor’s primary goals for the project are to increase plant availability, reduce non-productive time, and to substantially improve slab internal and external quality. The project will transform the existing two-strand, curved slab caster into a state-of-the-art vertical curved machine, with the application of all Danieli Davy Distington cutting-edge casting technologies. The ladle turret, tundish car equipment and casting floor structures will be used unchanged.
Danieli will manage the project on a turnkey basis, including complete dismantling of the existing caster, modifications to civil works and auxiliary systems, and installation of the new two-strand vertical curved machine. Danieli will also modify the slab discharge areas and maintenance areas, and install completely new electric and automation systems.
The existing machine is a curved design caster with a 12.2-meter radius and a metallurgical length of 33.4 meters. It utilizes a bottom-feeding dummy bar system, mechanical oscillator, and extraction of segments by crane for maintenance purposes. The new caster will be a vertical curved machine, with a vertical length exceeding 2.6 meters, main radius of 9.3 meters and a metallurgical length of about 36.2 meters. It will utilize a top-feeding dummy bar system, hydraulic oscillator and robot-type segment manipulator.
The top-feeding system, segment manipulator, high-performance equipment and maintenance-free design, together with increased supported length (designed for casting speeds up to 2 meters/minute), will enable an increase of plant productivity of about 10%, for up to 2.7 million tonnes/year of qualified slabs.
Arcelor’s product mix at Fos-sur-Mer includes an extremely wide range of steels, from IF grades for automotive applications to micro-alloyed steel (including X70 for pipe applications), medium Carbon, high Carbon and high-Silicon grades. To accommodate the wide product range, Danieli designed a new roll diagram to guarantee the advantages of the vertical design for internal quality (of paramount importance for IF grades) as well as superior slab surface quality (namely for crack sensitive, microalloyed, high-Carbon and high-Silicon grades).
Technological features of the new caster include an INMO mould (Danieli patent) and integrated hydraulic oscillator, OPTIMUM segments, and Peripheral Drill rolls. The new caster also features the dynamic soft reduction process, based on the liquid pool mathematical model, and a dynamic secondary cooling control system for air mist/water slab cooling.
Danieli Automation will develop and supply the complete electric and automation systems, including level 1 and level 2 control architecture.
Conversion of the machine will be executed during the main plant shutdown scheduled in the second half of 2007, timed to coincide with a blast furnace modernization. First cast for the new caster is scheduled to take place just 78 days after the last cast of the old machine. The time schedule, developed in cooperation with the Arcelor team, is based on Danieli's successful experiences with similar large-scale caster conversion projects at Posco, Korea, and ThyssenKruppStahl, Germany.
This order follows a project awarded by Arcelor in April 2005 for the conversion of the three two-strand slab casters in Dunkerque, presently under advanced execution stage.