For the manufacture of steel in electric furnaces, we take advantage of the heat generated by an electric arc which is created between the electrodes (one to tree) and the metallic charge contained in the baskets (ladles). Another possibility is to take advantage of the heat generated by the electric currents induced in induction furnaces, which production capacities smaller than the arc furnaces.
The basis of the steelmaking in electric furnace is the fusion of scrap as base load with later processes of refinement (adjustment of the chemical characteristics) of the molten bath.
As previously mentioned there are two major types of electric furnaces:
- Induction furnace (used for small productions): The scrap load is placed in a crucible surrounded by a coil through which an electric current is passed. It is the heat generated by the induced currents responsible for melting the charge.
- Electric Arc Furnace (EAF, employed for large productions): In arc furnaces, which are the most used in an industrial way, a powerful electric arc is created between the electrodes and the scrap load taking advantage of the heat generated by the arc itself. There are two major techniques, based on AC and three electrodes, in addition to the DC-based and single electrode.
As a complement to the electric furnace, in order to reduce costs with the improvement of the performance and reduction of electrical consumption, the operations of final adjustment and refinement in both chemical composition and temperature are done in a smaller arc furnace. Is the so-called: secondary or ladle metallurgy, done in a furnace called Ladle Furnace.
The refining process can be complemented by degassing processes of degassing (control of oxygen and nitrogen percentages) in vacuum atmosphere, required for special steels production.
Besides the electric furnaces, an electric steelmaking plant is usually equipped with a Continuous Casting Machine-MCC-, machine where the molten and liquid steel is poured directly into a mold whose bottom is adjustable either fixed or automatically, where the section of the semi-finished product to be manufactured is obtained.
The production in this type of machine depends on the number of strands composing them in addition with the final sections of the semi-products, ranging from the billets to the blooms for later long product rolling mill, to the slabs, used a posteriori like roughing material to obtain flat products.
Ingeteam supplies engineering, design, project management, programming, main & auxiliary electric drives, automation & control systems, electrical installation, engineering, commissioning, start up, training and maintenance on a turnkey basis for:
- Ladle metallurgy facilities: EAF & LF (level 1 and 2),
- Continuous casters (level 1 and level 2),
- Ancillary facilities: water treatment plants and pumping stations, scrap yards, de-dusting facilities, fully automatic additives management systems on EAF & LF.