Method and apparatus for deslagging and tapping an integrated electric steel making furnace

An electric steel-making furnace including the combination of:

• a furnace roof carried by an upper furnace shell on a lower furnace shell to substantially envelop an atmosphere above liquid steel and slag floating thereon in said lower furnace shell, said lower furnace shell having a refractory lining with a deslagging passageway in a sidewall thereof:
• a transfer car supporting said lower furnace shell for transport from a furnace operating site to a remote exchange site for exchanging one or more of said furnace roof, said upper furnace shell and said lower furnace shell, said transfer car including a wheeled carriage supporting a furnace support frame for tilting movement of the furnace support frame in a direction to alter the elevation of said deslagging passageway relative to said wheel carriage, said transfer car further including spaced apart rocker rails secured to said furnace support frame and engaged with spaced apart support rollers rotatably about two fixedly spaced axes mounted on said wheeled carriage;
• and
• a support including an actuator to tilt said lower furnace shell at said furnace operating site on said transfer car in a direction to increase the depth of slag at said deslagging passageway for decanting slag floating on liquid steel in said lower furnace shell.

A method for producing steel in an electric furnace, said method of including the steps of:

• providing an electric furnace including a transfer car supporting a lower furnace shell having a sidewall containing a deslagging passageway at an end of a floor wall opposite to a tap hole;
• refining consecutively steel heats in said electric furnace while residing on said transfer car at a furnace operating site for the furnace;
• decanting slag floating on consecutively refined steel heats by using said transfer car at said furnace operating site to tilt said lower furnace shell about two fixedly spaced axes on said transfer car in a direction to increase the slag depth at said deslagging passageway;
• tapping liquid steel from consecutive steel heats after decanting slag there from by using said transfer car at said furnace operating site to tilt said lower furnace shell about fixedly spaced axes on said transfer car in a direction to increase the liquid steel depth at said tap hole;
• transporting said lower furnace shell on said transfer car from said furnace operating site to a remote lower furnace exchange site;
• introducing a replacement lower furnace shell on said transfer car at said lower furnace exchange site;
• using said transfer car to transport said replacement lower furnace shell to said furnace operating site;
• and thereafter
• repeating said steps of refining, decanting, and tapping.