Daye Special Steel Co. Ltd., China, has awarded SMS group the contract to upgrade a 75-ton direct-current electric arc furnace (DC EAF) at its plant in Xinyegang, China.

Commissioning is scheduled for 2019.

As part of the upgrade the existing furnace will be scanned in 3D and the bottom part of the electric arc furnace vessel modified.

SMS group is supplying two new pin-type bottom electrodes and a high-current system with optimized arrangement to reduce deflection of the electric arc. Also the installation and commissioning will be supervised by SMS group.

The upgrade is aimed at reducing operating costs and increasing productivity. The pin-type bottom electrode requires no maintenance, and the condition of the electrode is continually monitored by thermocouples. The needle-shaped electrode boasts a long service life, and the optimized arrangement of the bus bar system means the refractory lining lasts longer. Thanks to the easy connection of the bus bar system, the furnace vessel can be changed in just a short period of time. For the lining, expensive conductive bricks have been replaced with cost-effective ramming mix. Safe working conditions for the operating crew are guaranteed as the bottom electrode is cooled with air and not water.

The DC EAF technology from SMS group offers a host of benefits: less power network interference, lower noise level, reduced electrode and refractory material consumption, and lower energy input.

The direct-current electric arc furnace generates a strong stirring motion in the steel bath, improving not only the temperature and homogenization but also the quality of the tapped liquid steel.