At the site of the oxygen-Converter shop of JSC "Mittal steel Temirtau", performed construction-Assembly works on the foundations and maintenance platforms for equipment, code of criminal procedure No. 3 with a capacity of 290 tons of production "SMS group", according to working documentation developed by the specialists of the NPD sevkazenergoprom LLP;.
Ladle furnace or ladle furnace installation, also called the complex steel processing unit (ACOS) — is a link in a single technological scheme with arc furnaces, converters and open-hearth furnaces to bring the metal into the ladle, after its release from the smelting unit, to a predetermined temperature and chemical composition.
Widespread in secondary metallurgy of steel got developed in 1971 by the firm Daido Steel (Japan) the process of refining in a ladle with the use of heated metal arc (process LF — Ladle Furnace). The installation that implements this process is called "ladle-furnace" (ACP).
The ladle furnace unit is used in combination with melting units in which the semi-product is smelted. As these aggregates are used in oxygen converters, electric arc and open-hearth furnaces, which are used for melting scrap and ferro-alloys with low waste and is carried out the oxidation period. Then the metal is poured into the steel, possibly excluding the ingress of furnace slag. Before and during the release of the metal in the bucket are given deoxidizers, slag-forming and alloying materials.
The bucket furnace unit is equipped with devices for the introduction of bulk materials (hopper overpass with weight-lifting devices) and trib-devices for the introduction of materials in the form of wire. Heating of the metal on the ACP is carried out as well as in arc furnaces (DSP), but the power of transformers of ladle-furnace installations is much less than that used in arc furnaces and is 100-160 kVA/t.this is due to the lack of such energy-consuming stage as the melting of scrap, heat is spent only on melting the input materials and maintaining the temperature of the metal. In addition, the power of the heat supply is limited by the increased wear of the bucket masonry above the metal level due to the small (compared to the arc furnace) diameter of the bucket. The specific energy consumption of the ACP is about 10 % of the total energy consumption for steel smelting.
During machining through the bottom of the ladle is blown metal inert gas (argon or nitrogen) for mixing the metal with the aim of averaging of its chemical composition and temperature, in addition, the scavenging metal facilitates the removal of nonmetallic inclusions from the metal. Gas injection is carried out through porous plugs, from one to three pieces on a large-capacity bucket. It is also possible electromagnetic stirring of the metal.
The use of ladle-furnace units allowed to take out of the smelting units recovery period and metal finishing, which dramatically increased the productivity of steel production. In the electric steel production, by eliminating the sharp drop in the oxidation of the bath, it was possible to significantly reduce the consumption of refractories, use single-slag technology and technology of working with the "swamp" (left in the arc furnace slag of the previous melting), which led to a significant reduction in electricity consumption.