Slag-free tapping of electric furnace of technology sharing

To achieve slag-free tapping of electric furnaces, traditional tapping methods need to be changed. The rapid progress of electric furnace technology is not only reflected in the number of electric furnaces, but also the furnace type and tapping mechanism and control methods are constantly changing and updated, making the electric furnace slag-free tapping technology more perfect and diversified.

Electric furnace slag-free tapping technology

CBT (central furnace bottom tapping)

In 1979, Thyssen Steel Plant in Germany first put into production a 50t central bottom tapping (CBT) electric furnace. The eCBT electric furnace has a simple structure, enlarged the water-cooling area of the furnace wall, and can input electric energy to the maximum. But it cannot tap steel without slag. To overcome this shortcoming, in 1983 the company developed a 100t eccentric bottom tapping electric furnace. Since then, some new tapping technologies have been developed one after another.

OBT (offset bottom tapping)

OBT oval furnace shell is similar to EBT. However, there is no tapping box, which is similar to the CBT method. This method has a large tapping hole angle and a large distance from the center of the furnace bottom.

The basic idea of the OBT electric furnace reformed in Italy in 1988 is: the best efficient energy input, easy maintenance, simple process control, economical, and improved productivity. The bottom tapping system of the furnace is offset on the side of the long axis, and the tapping water is controlled by sliding water & the main operating results of the furnace: electric energy consumption is less than or equal to 390kWh/t, electrode consumption is less than or equal to 2.5kg/t, refractory material consumption Less than 3.7kg/t, the tapping cycle is 64min,

RBT (bottom tapping method)

RBT is a round bottom tapping method. The tap hole position is within the circumference of the furnace bottom, which has no low temperature zone and reduces the amount of slag entrapment during tapping. During the tapping process, there are continuous weighing of the tapping amount and continuous measurement of the tilting angle of the furnace. Fully automatic tapping operation. The RBT tapping method can reduce the amount of spare parts for the water-cooled furnace wall of equal height, increase the water-cooling area of the furnace wall, and facilitate the construction of refractory materials on the furnace wall and slag line. The tap hole filling operation is completely controlled by remote control. The sliding plate system for opening and closing the tapping hole adopts a water-cooled jacket and a heat-proof design with spray coating. When the sliding plate of the tapping hole is mis-operated, there will be no accidents. In fact, the current popular EBT design requires "short and high", that is, the tap hole eccentric distance should be as short as possible, and the small furnace cover in the eccentric area should be as high as possible. This shows that the design of EBT is unconsciously developing in the direction of RBT.