RU1836442C - Chamber unit for melted metal refining - Google Patents

Abstract

Usage: smelting, namely out-of-furnace processing of steel in the ladle during its refinement before casting in continuous casting machines or in molds. SUBSTANCE: installation includes a casting ladle with a coaxially located lifting and lowering lined hollow cylinder, inside which a movable purge tuyere is coaxially placed, and its inlet part is provided with a groove for introducing additives, for example, ferroalloys; In the upper part of the lined cylinder tangentially on its lateral surface, burner devices are installed, equipped with fuel and oxidizer feeds. 2 ill., 1 tab.

Description

The invention relates to the field of metallurgy, and more particularly to smelting, and can be used for out-of-furnace processing of steel in a ladle during its refinement before casting into a continuous casting machine or into molds,

Another known similar solution to the same problem involves blowing molten metal with an inert gas using a vertically suspended lance (2).

These known solutions also include the addition of additives, e.g., ferroalloys and various additives (3), from above into the casting ladle.

These solutions have significant drawbacks in that they have a low degree of processing of steel, associated with poor degassing of the melt and significant removal of metal from the ladle,

In order to increase the efficiency of steel processing, the casting ladle is placed in a chamber sealed with a lid, equipped with a suction, a blowing lance and the introduction of ferroalloys (4).

According to this known solution, the metal is vigorously mixed in a ladle by purging with an inert gas and evacuating the exhaust gases by suction (pump) from the chamber, which increases the degree of metal degassing.

However, this technical solution is characterized by significant disadvantages associated with possible emissions of metal during its boiling during purging, the difficulty of sealing the chamber, the bulkiness of the structure and significant energy consumption, as well as the need for a developed energy economy.

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As a result of the above, the processing efficiency of the steel, and hence its quality, is reduced.

The closest in technical essence and the achieved effect is a chamber installation for lapping of molten metal, including casting steel ladle with a coaxially located lifting and lowering lined hollow cylinder, inside which a movable blowing lance is coaxially placed, and its inlet is equipped with a groove for introducing additives, for example ferroalloys and other materials (5).

An object of the present invention is to improve the quality of steel by increasing the efficiency of processing it in a casting ladle, in the process of finishing it.

The technical result is achieved in that in the upper part of the lined cylinder, tangentially on its lateral surface, burner devices are installed, provided with fuel and oxidizer, This leads to the fact that the inner surface of the lining, outside the zone of molten metal, is supported by burner devices at a temperature level not lower than the melting temperature of the seated materials, which contributes to the melting of fine particles deposited on the surface and their descent (runoff) in a liquid state in the melted steel. This also reduces heat loss with the surface of the metal mirror in the cylinder cavity. In addition, the result is achieved by the fact that the tangential installation of burner devices leads during their operation (with the formation of the vortex movement of gases and, as a result, the creation of a stable realizable vacuum inside the vortex, which contributes to the active degassing of molten steel directly from its clean surface located in the cylinder cavity.

In FIG. 1 and FIG. 2 schematically shows a chamber installation for lapping molten metal.

It includes a casting ladle 1 with molten steel, coaxially with the ladle on its lid there is a lifting and lowering lined hollow cylinder 2, inside of which a movable purge lance 3 is placed along its axis, and its inlet part is provided with a groove 4 for introducing additives into the cylinder cavity. Depending on the size of the bucket 1, i.e. its capacity, the inner diameter of the cylinder 2 is 600-1200 mm, and its height is 1800-2200 mm, while the total thickness of the lining on the side is approximately 230 mm.

In the upper part of the cylinder 2, at a distance of 1 / 3-1 / 2 of its height, burner devices 5 are installed, equipped with fuel and oxidizer inlets 6 and 7, respectively.

The installation works as follows.

A casting ladle 1 with a spout discharged from the furnace is installed under a vertical lifting and lowering lined

hollow cylinder 2, which is immersed with the lower part in the melt (200-400 mm), while the metal mirror in the bucket outside the lined, hollow cylinder is protected from oxidizing agent by slag, and inside the cylinder 2

they are left clean, where ferroalloys with alloying elements and deoxidants are introduced through the trough 4, which are introduced into the cylinder 2 from above in the form of lumpy (crushed) materials and mixed with the melt by blowing through a movable blow-out immersion lance 3.

Argon or nitrogen are used as the gas for purging the melt. Bottom cut

lances 3 are in the metal volume at a distance of 500-1000 mm from the bottom of the bucket 1. The blowing time for homogenizing the metal in the volume of the bucket is 3-5 minutes, for stirring to

refining liquid steel for 5-10 minutes. In the process of flowing out from the lance 3, in the melt, the gas trickles disintegrate into small bubbles and are carried out through the mirror of the unprotected slag metal, in this case

through the cavity of the cylinder 2. The rate of gas evolution from the liquid metal will increase when a vacuum is created above the metal mirror. To refine steel in the ladle into pure metal, ferroalloys with alloying elements, for example FeCr, SiMn, FeSI and deoxidizers, are placed on top of the ferrous alloy through the cylinder cavity and mixed with the melt during the purge process. The intensity of the bubbling

melt and gas evolution from the melt

increasing. At the same time, the inner surface of the cylinder liner above the boundary of the molten metal is maintained at a temperature level not lower than

0 the maximum melting temperature of the loaded materials (additives), for example ferroalloys, by its additional heating by burners 5. In this case, dust particles (finely dispersed

5 fractions of additives) are melted and upon contact with the surface of the lining together with droplets of entrained metal will flow into the melt in liquid form, while their subsidence on the lining ceases, which eliminates arsenic formation.

For forced and economic facilitation vydoleng "s: p: -: -

the process of melting the particles on the surface is ensured by at-p-at: i-kg;

lining is almost enough podskogo uniformity. IYPYAPNMRLNR

keeping its temperature at 20-70 ° C of the sample in the volume of stllm. s cm - w

above the maximum melting temperature, 5 the increase is uniform; } m;

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temperature of the introduced additives. Sub-properties. Input in such a (pre

Zhanio of such temperature level is deoxidized) methll l «m; p: oishkh

takes into account the swelling of the droplets of metal that have settled, provides in the process r.0p; .r ovi n m

on the lining from its surface back to the purer steel according to GP, .1 :;

 liquid metal, keeping the lining clean, 10 metal ones included; pi G, neither, and: on which there are no conditions for the formation of a metal of a minor irmmog:; -:

no accusations. Thus, on the path of y-forming elements y. -ix-v-; -.

staple additives, there is no crippling effect of nitrogen.

(increased hydraulic resistance. Cleanliness ob-fiu am: ;; - 1:

lenml) from the side of nastily, which increases the uniformity of the hmmsosgl15;;: ofic .n ":

quality of steel finishing (from the point of view, the stability of the properties of the metal; on;:

small platoon of additives) and uniformly-within the ingot and pomkr. my;:; / sgm -

the ability to remove flue gases. At the same time, steel at any sg.sg.g -;.; bc - device The suction of air to the mirror will become clean. ozh: ;; - -; p-th metal, and the temperature potential 20 performance elpp.l-nmp.;:

. introduced additives is increased - due to costs, to reduce the consumption of l "tgru-oi:; ; ..;

countercurrent effect of high temperature - will reduce; -. ----- .--. :.,; m /.-1

of gas and increasing their velocity. It should also be noted that oop.o

a predetermined vertical cavity cavity volume according to the given general crew 0.:.

cylinder. Keeping a clean outlet 25 requires minimal. n : .---. ;

the path directly above the metric cost mirror mm eo p g :: g: m-: tzll increases throughput complicates ei technology; pp ::: op;

emitted gases. For additional year-old steel.-Flax: ..-:;.

their allocation at a given degree. before-so obzzz .. i.ie; i; .-; i ..-- p

meshig ;. melt over the mirror of the purely-30 invention will not;. ;; h .-. mp-;:; -;

It is advisable to maintain the processing by means of streaming; ; ..- .;

. Reg / Chuu: My Discharge. This technical education in the zo ;;: about

A positive result is achieved by forced-gases, reduction of dust extraction pr ;; : -gp

with exhaust gas from the mirror of pure additives and short-circuiting; to d |; op

metal by installing burner devices of the degree of legazetsi degree: -;: (ROYS - In 5 tangentially lateral surface heating of the implant

cylinder 2, reduced choke 1x;

P. | 4, low (tangential) input reduction of heat loss h:;:: ::

energy source, in which quality is the cylinder. As a result, pprnchs -. /

I use a fuel-oxidizing mixture, the quality of O5roG-O1, which is given under pressure by means of melt, is melted by 40. profitability of the process

burners 5 about the cavity of the cylinder 2; An example of a specific projection is created;

reduced pressure, contributing to the electrodes e ..,:;; but:

boiling of deoxidized steel, which is of the Khalilovsky Metksmb. nptg;

attenuation upon reduction of atm-45 Initial data: Oo; .to

farm pressure. When creating an insignificant-steel-pouring kogmi e -: -; soft gravity boiling metal

renewed and amplified by an increase. Hermetic .n-tp.

rarefaction. Boiling is caused by:

pouring dissolved gases in the metal, i.e. 50 - height - 1800 mm;

by changing the discharge above the surface. -diameter int. - H-.Pmm

nostyo metal can be carried out pro- diameter outside. Yu. B-m.

process of degassing controlled. Due to the depth of immersion tsipm.

a decrease in the partial pressure of hydrogen melt is 200-300 mm.

and nitrogen, these gases are released from 55 Characteristics of Fut ro;. ;; -.

liquid metal as by desorption from a polonemist with a content of- /-.;. and

surface and diffusion of dissolved gases Installation cylinder - P

in the surface layer, and by way of a diffusion-melting ladle, coax.-o.r.v,

Zii o pop-up bubbles of carbon monoxide-Heating cylinder 3

sort and desorption in the gas phase. Due to the air burners.

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Natural gas consumption for burners 30-50m3 / h.

Installation of burners - on the lateral surface of the cylinder, tangentially to it, at a distance of 1100 mm from the lower end of the cylinder.

Characteristics of additives loaded into the steel pouring ladle - lump - FeCr; SlMn; FeSl et al., Fractions up to 2 mm - 10-15%, tnn 1540 ° C.

Characteristics of the processed steel quiet crack-sensitive grades like 40 X,

A comparison of the method under consideration was carried out in comparison with the solution taken as a prototype and the steel lining used in the chamber installation.

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Pilot Test Results

Marriage of the first redistribution (cracks, flaws),%

The volume of metal with oxide inclusions of 5 or more

point,%

The nitrogen content in the metal,%

The hydrogen content, ml / 100 g Not

r..HLЈ§J I iV.-PyLPT

Cap

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When compiling samples of 10 swimming trunks of the compared solutions, the following average practical results are obtained, presented in the table.

Claims (1)

SUMMARY OF THE INVENTION A chamber installation for lapping molten metal, comprising a casting steel ladle with a coaxially arranged lifting and lowering lined hollow cylinder, inside of which there is coaxially placed a suspension to the purge lance, and its inlet part is provided with a groove for introducing additives, for example, ferroalloys, characterized in that in the upper parts of the lined cylinder tangentially on its lateral surface are equipped with burner devices equipped with fuel and oxidizer feeds. FIG. I