Features of EBT electric arc furnace

The structure of the EBT electric furnace is to change the tapping trough of the traditional electric furnace into a tapping box, and the tapping opening is vertically downward at the bottom of the tapping box.

The lower part of the tap hole is equipped with a tap hole opening and closing mechanism to open and close the tap hole. The top center of the tap box is provided with an operation port to facilitate the operation and maintenance of the filler of the tap hole.

Advantages of EBT electric arc furnace

The main advantage of EBT electric furnace is that it realizes slag-free tappingand increases the use area of water-cooled furnace wall. The advantages are as follows:

(1) Reduction of tapping tilt angle. Simplify the tilting structure of the electric furnace: reduce the resistance of the short network: increase the use area of the water-cooled furnace wall and improve the life of the furnace body.

(2) Retaining steel and slag operation. Slag-free tapping improves steel quality and is beneficial to refining operations: leaving steel and slag is beneficial to electric furnace smelting and energy saving.

(3) The bottom of the furnace is tapped. Lower tapping temperature, save power consumption: reduce secondary oxidation, improve steel quality: increase ladle life.

Due to the many advantages of EBT electric furnaces, it has rapidly gained popularity worldwide. Now the construction of electric furnaces, especially the electric furnaces matched with the refining outside the furnace, must require slag-free tapping, and EBT is the first choice.

The tapping operation of EBT electric furnace. When tapping, after tilting about 5° to the tapping side, the tapping mechanism is turned on, and the tapping filler automatically falls under the action of the static pressure of the molten steel, and the molten steel flows into the ladle to realize automatic pouring and tapping.

When the molten steel reaches about 95% of the required level, it will quickly back to prevent slag. In the back tilting process, about 5% of molten steel and a little slag will flow into the ladle. After the furnace is shaken (10%-15% of steel is left in the furnace, Residual slag ≥ 95%) Check and maintain the tap hole, close the tap hole, add fillers, load scrap steel, and restart the arc melting.

The smelting process of EBT electric furnace

EBT electric furnace smelting has changed from steelmaking equipment that included melting, oxidation, reduction refining, temperature, composition control, and quality control in the past to chemical steel equipment that only retains melting, heating, and necessary refining functions (dephosphorization, decarburization). And transfer those process operations that only require lower power to the ladle refining furnace.

The ladle refining furnace can provide various optimal refining conditions for the initial molten steel, and can strictly control the composition, temperature, inclusions, and gas content of the molten steel to meet the increasingly stringent requirements of users for steel quality.

Dephosphorization, even partial decarburization, should be advanced to the melting period as much as possible, while the oxidation refining and heating period after melting only controls carbon and is not suitable for the addition of ferroalloys that are easier to oxidize and are added in a larger amount during the charging period. Melting is particularly beneficial to shorten the smelting cycle, reduce consumption, and increase productivity.

The EBT electric furnace adopts steel and slag operation.  At the beginning of melting, there is a ready-made molten pool, supplemented by enhanced oxygen blowing and bottom blowing and stirring, which provide good conditions for the advance metallurgical reaction. From the perspective of improving productivity and reducing consumption, electric furnaces are required to have the shortest melting time, the fastest heating rate, and the least auxiliary time (such as furnace repair, feeding, electrode replacement, steel tapping, etc.) in order to achieve the best economic benefits.