SU575373A1 - Method of alloying liquid steel - Google Patents

Description

I

The invention relates to the field of metaphoria and can be used with vy-. high quality smelting; steel.

Methods are known for introducing alkali and alkaline earth metals into liquid steel with a bell immersed in liquid steel l, through nozzles located in a drain or in the wall of a vessel with 2J liquid steel, and by introducing alkaline earth metal vapors under the level of the melt through holes in special-. capacity, and the number of injected vapors regulate the number and size of holes in the tank. However, it is noted the introduction of lightly vaporized additives in the form of vapors, which form bubbles of liquid steel, which quickly pop up from the metal. In a short period of time the bubble remains in the volume of liquid steel, only a small fraction of the alkaline earth metal input is absorbed.

There is also known a method for the introduction of alkali and alkaline earth metals, according to which, in order to increase the absorption of their modifiers

are introduced with the simultaneous entry of gas under pressure through a refractory tube immersed in the melt 4 ,. However, this type of activity also does not provide a high digestibility of the modifier, since (as the modifier is introduced in the form of vapors that form fast-erupting bubbles.,

Claims (4)

The purpose of the invention is to increase the absorption of alkali and common earth metals during alloying of liquid steel. This is achieved by introducing into the melt an iron-silicon-alloys ligature saturated with vapors of alkaline and alkaline-earth metals. To do this, use liquid iron nickel, silicon ligature, which is preliminarily saturated with vapors of alkali and alkaline earth metals under an excess pressure of 0.03-3.5 atm until a mobile equilibrium between metal and vapor is established. The magnitude of the saturation vapor pressure of alkali and alkaline earth metals is established depending on the amount of alkali and alkaline earth metals introduced into the steel melt and on the depth of insertion of the alloy under the mirror of the liquid steel. The saturation of the nickel and nickel-silicon nygatura with alkaline vapors of land / metal metals under pressure was less; 3,5 ati is not feasible due to the insignificant equilibrium concentration of these metals in the ligature. Saturation of the nickel-iron-silicon alloys with alkali and alkaline-earth metal vapors under a pressure of less than 0.03 MPa does not provide the advantages of the proposed method, since in this case, the depth of the bath of liquid steel should not be less than 5.0 m in order to introduce the ligature. steel production. To regulate the content of alkali and alkaline earth metals in steel, they change the saturation pressure of the nickel-silicon alloys with vapors of these metals, and, if necessary, increase the saturation pressure and proportionally increase the depth of introduction of the ligature, taking into account that one excess atmosphere is balanced by a column of liquid steel with a height of about 1 4 m. To reduce the content of alkali and alkaline earth metals in steel / reduce the saturation pressure and the depth of introduction of the ligature. The amount and composition of the injected liquid ligature is determined by the chemical composition of the treated strain. PRI% MEUR. The method was tested for doping steel 38H4MPA with calcium in coc & with a capacity of 10 tons. In a sealed lined container with a stopper iron nickel silicon ligature (nickel; 18.5% silicon; the rest is iron) in an amount of 0 kg is saturated with calcium vapor at a pressure of 0.75 atm for 5 minutes. Then the vessel with a ligature on the rod is lowered into the ladle to a depth of 1 Ω, open the container stopper and the ligature is introduced into the molten steel. Calcium absorption 95%. The introduction of calcium is not accompanied by a pyro effect and metal splashes from the ladle. The absorption of alkali and alkaline earth metals by steel is increased by 5-10 times. The reduction in the cost of steel is 10-20 rubles / ton. In addition, completely eliminate pyroeffect. DETAILED DESCRIPTION OF THE INVENTION A method for alloying liquid steel, comprising introducing alkali and alkaline earth metals into the melt under pressure, characterized in that, in order to increase the absorption of alkali and alkaline earth metals, an iron – smelter alloy filled with alkali and alkaline earth metals is introduced into the melt. Sources of information taken into account in the examination: 1.Patent of Switzerland No. 382783, cl. 18 1} 7/00, 1959. 2. The patent of Germany No. 123539, cl. 180 1 / О8 3. Patent Franic N 224O292, cl. From 21 to 1/00, 1973. 4. USSR author's certificate N 471384. cl. C, 21C 1 / OO, 1973