Electric Arc Furnace

1. EAF Introduction
2. Developments in EAF Technology
3. Basic Equipment and Operation
4. Furnace Layout
5. Electrical Equipment
6. Melting
7. Burners
8. Raw Materials
9. Raw Materials Preparation
10. Alloy Yield
11. Electrode Breakage
12. Slag Foaming
13. Slag Foamability
14. Slag Reduction
15. Deslagging
16. Tapping
17. Exercise: EAF Operation
18. EAF Simulation

The melting stage in the EAF starts when the operator switches the furnace power on after charging the first basket. From that point and onwards the operating conditions of the EAF changes throughout the heat, starting with melting of cold scrap and ending with superheated liquid steel at a temperature above 1650 °C.

By adjusting the transformer tap setting, the operator may adjust the power input according to the present operating conditions, thus striking a balance between maximum melting and heating rate and an acceptable thermal load on the equipment, especially furnace roof and walls.

Maximum power is utilized during the main part of the melt-down periods. Reduced power is used during the initial stages after scrap basket charging, when the arcs are close to the delta section of the furnace roof, and during the refining period when operating under "flat bath" conditions in order to reach the target temperature.

By adjusting the furnace secondary voltage (by selecting tap setting) the arc length is changed to obtain optimum operating conditions.