The process begins with placing steel from our scrap yard into a charge bucket. Because each “heat” is custom-made even the composition of scrap that goes into the charge bucket is quite precise. Loaders follow a specific recipe for each of our customers.
At the bottom of each charge bucket is a clamshell door. Crane operators hoist each charge bucket over the electric arc furnace open the doors, and drop their load of scrap steel. If you happen to see this process in person, be prepared for a little heat. It takes two charges to make a heat of up to 170 tons of molten steel.
Once the charge is unloaded the furnace is covered, and electrodes are lowered through the top of the furnace. The electrodes are lowered near the scrap, inched back up and electricity “arcs” to the steel.
Again, if you happen to see this process in person you should know that this is the loud part. And understandably so: The electric charge coursing through the furnace is anywhere from 130 to 170 megawatts strong. In a matter of 45 minutes the scrap steel is reduced to molten steel at approximately 3,000° Fahrenheit.
The molten steel is then tapped through the bottom of the furnace into a ladle. Each batch of molten steel is called a “heat;” on average, one heat will produce six coils of steel.
The average heat is converted from molten steel to a solid coil in a short amount of time. In fact, steel that was in our scrap yard in the morning can be in the form of a coil by the afternoon.