Electric Arc Furnace

Electric Arc Furnace (Direct/Indirect)
Points : Electric Arc Furnace (Direct/Indirect), Definition Definition Electric-arc furnaces offer the advantages of high thermal efficiency, rapid heating close temperature control and strict atmospheric control. All of these features are desirable in the production of commercial-quality metals, Direct-arc furnaces derive their heat from the electric arc between electrodes and the material to be melted.
The electrodes may be made out of carbon or graphite, making then non-consumable electrodes; or they can be consumable electrodes comprised of steel rods with carbon cores. Indirect arc furnaces are normally horizontally mounted cylinders which can be rotated through an arc of 1800. The carbon electrodes or the steel-tube carbon electrodes are mounted along the horizontal axis of the furnace and automatically adjusted to maintain the correct distance for the proper arc column. In the indirect arc furnace, the arc never touches the metal rather; the metal is melted by radiation from the heat produced by the arc and by conduction from the heat absorbed by the refractory lining. As the furnace is rotated, the refractory lining is heated and rotated, and forth, exposing the melt to a larger area of the heated lining. As in all ferrous melting furnaces, the basic or acid composition of the liner determines the type of ferrous material produced.