SU486057A1 - Melting method in an arc furnace - Google Patents

Description

one

The invention relates to ferrous metallurgy, in particular, to steelmaking in arc furnaces.

Known methods of melting in arc furnaces in which the following methods of lining protection are used: stabilize arc burning by using hollow electrodes, blowing argon; shields the arcs with steam, natural gas, or by continuously loading fine crushed scrap; water-cooled structural elements are used; rotate vapnu, etc.

The known method of steelmaking in a four-electrode furnace. The smelting process includes charging the melting agent, melting it with the subsequent heating of the metal with open arcs while all heating sources are working simultaneously. However, during the period of open burning of arcs along the perimeter of the inner surface of the lining against the arcs, there are formed thermal pressure zones, in which the lining temperature is 1 max. This leads to rapid wear and reduced lining life.

The purpose of the invention is to increase the durability of the lining.

For this, during the open arc period, one of the heat sources is disconnected and when the maximum application temperature of the material is reached, for example, for magpesite 1650-1700 ° C, for heat-resistant chromomagnesite 1750 ° C, one of the opposite sources is turned off neighboring sources with simultaneous switching on of the originally disconnected source, repeat cycle on - off in a sequence ensuring the one-directional movement of the thermally stressed lining zone along its perimeter etru.

The melting method is carried out as follows.

Charged into the furnace, include four sources of heating and lead to melting. At the moment of opening the arcs, one of the sources of heating is turned off and the further heating of the metal is carried out with three arcs until the lining temperature reaches the maximum temperature at which the material is changed. In this case, the thermal stress of the op is located against the middle electrode (source). Then, the initially disconnected source switches on and simultaneously disconnects the neighboring heat source. This leads to the fact that the thermally stressed zone moves around the perimeter to a new position and is also located against the average of the three working sources. The described switching on and off cycle is then repeated until the required temperature of the metal is achieved in a sequence that ensures the movement of the thermally stressed zone in one direction.

Subject invention

The method of smelting in an arc furnace with four sources of heating, including melting the mixture with subsequent heating of the metal with open arcs, is characterized in that, in order to increase the durability of the lining, during the open arc process, one of the sources of heating is turned off and the middle of the included sources disable one of the adjacent

sources with simultaneous switching on of the originally disconnected source, repeat cycle on - off in a sequence that provides for unidirectional movement of the thermally stressed zone

lining along its perimeter.