The process of quality steelmaking is an intricate process requiring skilled operators as well as state-of-the-art equipment.
Step 1 -
Scrap is loaded into clam shell buckets and charged into the ultra high powered (UHP) eccentric bottom tapping furnace (EBT) electric arc furnace. Scrap is melted. Carbon and phosphorous are refined under oxidizing slag.
Step 2 -
The EBT feature minimizes temperature loss and allows liquid steel to be tapped slag-free into the ladle for further refining. During tapping, deoxidation and alloy additions are charged following by the addition of a reducing top slag.
Step 3 -
The ladle is transferred to the heating station for alloy adjustment and refining. Arc heating and induction stirring at this step ensures mixing and interaction of steel and slag.
Step 4 -
The steel bath undergoes vacuum degassing where hydrogen is refined to a level of less than 1 part per million. Combined induction and argon gas stirring is used to optimize stirring energy during vacuum treatment.
Step 5 -
The ladle is transferred to a second heating station where steel may be calcium treated via wire feeding. The steel may be reheated and final alloy adjustments added if needed.
Step 6 -
Heats are sent to teem at a consistent, designated temperature. All ingots are bottom poured at a controlled rate of rise. Argon shrouding may be employed to minimize re-oxidation and the pickup of hydrogen and nitrogen.