Eccentric Bottom Tapping (EBT) Furnace
Product Description
Eccentric Bottom Tapping EAF
An electric arc furnace (EAF) is a steelmaking furnace that melts metallic charge materials by means of electric arcs generated between graphite electrodes and the charged material.
Unlike induction furnaces, the charge material in an EAF is directly exposed to the electric arc, allowing faster melting, higher bath temperatures, and more effective refining operations. Modern EAFs are widely used for the production of carbon steel, alloy steel, stainless steel, and special steels.
EBT (Eccentric Bottom Tapping) is an advanced tapping method widely used in modern EAF steelmaking.Compared with conventional side tapping furnaces, the EBT design adopts an eccentric bottom tapping system, which allows molten steel to flow out through the furnace bottom while minimizing slag carry-over.
The EBT system offers the following advantages:
•Better slag-free tapping performance
• Lower phosphorus reversion risk
•Reduced alloy consumption
•Lower temperature loss during tapping
•Shorter tapping time
•Improved steel cleanliness
•Higher automation level
•Longer refractory service life
Main parameter of electric arc furnace (EBT)
| Type | Inner shell (mm） | Rated(t) | Transformer | Reactor(Kvar) | Graphite(mm) | |
| Rated/Max | Rated (MVA) | |||||
| HX-30 | 4600/4800 | 30/45 | 25～32 | 0～7000 | 450 | |
| HX-60 | 5400 | 60/70 | 45～55 | 9000～11000 | 500 | |
| HX-80 | 5800 | 75/85 | 60～70 | 12000～14000 | 550 | |
| HX-100 | 6200 | 100/120 | 75～85 | 15000～17000 | 600 | |
| HX-120 | 6400 | 120/140 | 90～110 | 18000～22000 | 650 | |
| HX-150 | 6800 | 150/170 | 120～130 | 24000～26000 | 650 | |
A typical CHNZBTECH EBT electric arc furnace is designed with mature technology, reliable performance, and stable operation.
The furnace mainly consists of:
•Upper and lower furnace shell
•Water-cooled roof
•Electrode arm and lifting system
•Secondary electrical circuit system
•Furnace tilting mechanism
•Roof lifting mechanism
•Hydraulic system
•Water cooling system
•Compressed air system
•Oxygen lance system
•Ladle and ladle car
•High-voltage and low-voltage electrical systems
•PLC automatic control system
•Computer monitoring system
During tapping, the furnace tilts approximately 5° toward the tapping side. The EBT tapping mechanism is then opened, allowing the tapping sand/filler to flow away under the static pressure of the molten steel. Molten steel subsequently flows smoothly into the ladle through the eccentric bottom tapping channel.
Because the tapping hole is located at the furnace bottom, molten steel is discharged first while most of the slag remains inside the furnace, significantly reducing slag carry-over.
When approximately 90–95% of the molten steel has been tapped, the furnace is quickly returned to prevent excessive slag from entering the ladle. A small amount of residual steel and slag is intentionally retained inside the furnace (hot heel operation), which helps accelerate the next heat and improves arc stability and foamy slag formation.
Typical slag retention rate can reach ≥95%.