By Cameron Chai
Siemens VAI Metals Technologies has received the final acceptance certificate from Çolakoglu Metalurji, a steel producer in Turkey, in August 2011 for upgrading the electric arc furnace no. 1 at the Gebze Plant, within four days following the first heat.
Çolakoðlu Metalurji steel works in Gebze, Turkey. Electric arc furnace no. 1, modernized by Siemens, is one of the most productive in the world.
Being already one among the high-productivity electric arc furnaces in the globe prior to upgrading, performance of the electric arc furnace no. 1 has been considerably enhanced by increasing the electrical active power input by 8% and decreasing its consumption of electrical energy by 6%, while maintaining the same consumption of fossil energy. This has increased the electric arc furnace’s overall productivity by 12% but maintained the tapping weight.
Çolakoðlu has been using a Siemens VAI Simetal Ultimate electric arc furnace for the production of steel since January 2007. The furnace was initially fabricated for 250 t of charge volume with a two bucket charge operation. Meanwhile, the furnace was run with 315 t of tapping weight, resulting in an improved cycle time with over two scrap buckets charge caused by the availability of scrap with lower density and higher tap weight.
According to the upgrading project, a larger part of the electric arc furnace’s mechanical equipment, including furnace cover, lifting columns, gantry, upper and lower shells, is renewed. These upgrading works raised the shell volume by nearly 20%, but do not increase the tapping weight. Thus, the furnace is now able to be charged again with only two buckets and manufactures more than 2.5 Mt of steel annually. The project also included the installation of current carrying electrode arms for electrodes with diameter of up to 800 mm.