ARC STEEL-MELTING FURNACE WITH HEATING OF A CHARGE IN THE FURNACE STACK AND A METHOD OF REALIZATION OF A MELT IN THE FURNACE Russian patent published in 2005 - IPC

FIELD: metallurgy.

SUBSTANCE: the invention is dealt with metallurgy and includes a group of inventions. In the arc steel-melting furnace the furnace stack for heating of the charge is located axis-symmetrically on the side of the furnace roof over the space indicated by three current-carrying electrodes a phase by a phase connected to the secondary coils of the three-phase mains transformer, and axis-symmetrically in relation to the area of meeting of prolongation of the axes of these electrodes in the working space of the furnace. At that the lower cross-section of a plane of the stack on the junction with the furnace roof or the furnace body is made with a stacking factor equal to 0.3-1.0 of the furnace roof area at its counting along the horizontal section in a place of the junction of the furnace roof with the working space of the furnace. The current-carrying electrodes are located on the side of a lateral part of the furnace or the furnace roof, axes of which in respect to a horizontal plane make 0° or they are inclined in the direction of a charge loading at an angle up to 90°. The method provides, that the stack for heating a charge is located axis-symmetrically in respect to a bath of the furnace above three electric arches blazing between electrodes or between a charge and electrodes, which are positioned on the side of the lateral surface with joining of the electric arcs in axial area of the furnace or on a charge. Simultaneously the area of blazing arches is fed with a voltage through a hearth conductor and a current-carrying charge and the direct current is withdrawn from its source through electric arches and electrodes to the zero point of windings of the three-phase mains transformer or to the three-phase group of an inductive impedance connected under the circuit of a "star"-type. The invention allows to improve uniformity of metal heating and heating of a charge in the stack, to improve stability of electrical alternating-current due to input of a direct current arc, to expand the lower cross-section of the stack and to reduce an aerodynamic resistance to the heated gases run through it, and also to redistribute a part of the radiant energy from a lining onto a surface of a charge of the lower cross-section of the stack.

EFFECT: the invention ensures improve uniformity of metal and a charge heating in the stack, stability of electrical alternating-current, expansion of the stack lower cross-section, reduction of an aerodynamic resistance to the heated gases run, redistribution of a part of the radiant energy.

5 cl, 3 dwg