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A major revamping operation is being initiated step by step at Acindar, Argentina's largest private steelmaker. So far, a saving of US$36 per tonne has been achieved. Ongoing measures include the commissioning of a unique inclined mould continuous billet caster and the revamping of roughing and bar mills.
Acindar, Industria Argentina de Aceros SA is the major privately owned steel manufacturer in Argentina. The company produces a broad spectrum of steel products ranging from plain carbon steel to high alloyed steel grades. End products include wire rod, wires, wire ropes, skelp for cold rolling applications, pipes for standard and oil industry use, forgings, billets and bars for the automotive industry.
Steel production is by the route, direct reduction - electric arc furnace - continuous casting. The Midrex direct reduction module is one of the most efficient and productive in operation.
The company started operations in 1943 with the production of steel by open hearth furnaces. The first electric arc furnace was started in 1962.
In 1981, the company merged with Gurmendi SA, the other major steel producer in the country. At that time, both companies operated four different plants with twelve electric arc furnaces with tap weights ranging from 10 to 120t and several rolling mills.
An on-going rationalisation program has been embarked upon with the assistance of Krupp Stahltechnik GmbH, with the objects of improving productivity and quality while reducing costs. The steelmaking, rolling and forging areas are all being examined to realise this aim.
STEEL MELTSHOP
Main steelmaking operations have been concentrated in one 45-50t unit, plus one smaller furnace dedicated only to a few grades which are required only in small lots due to market conditions. It is foreseen that this furnace will also close with smaller heat sizes being produced by tapping of partial heats followed by processing in a VD/VOD-unit to be erected.
Power Supply
The surviving furnace has been entirely rebuilt and is now an ultra high power unit. As productivity is one of the major issues for this furnace, a 1000kVA/t ratio was adopted using an available transformer rated 45/65MVA. To complete the electric design, a comprehensive high voltage study was developed to select the best transient overvoltage protection for the system. The furnace transformer is fed...