RU63271U1 - BLOWING BLOCK AND DEVICE FOR BLOWING A LIQUID METAL WITH A GAS IN A DUCK (OPTIONS) - Google Patents

Abstract

A group of utility models relates to ferrous metallurgy, in particular to devices for treating liquid metal with gas in a ladle.

The objective of the utility model group - a device for purging metal with gas and the purge unit used in it - is to increase their efficiency and reliability.

The blowing unit is generally made in the form of a rectangular parallelepiped of dense refractory with vertical gas-conducting channels of capillary shape, the upper part of at least one side surface, comprising 50 ± 10% of the total height of the block, made with an inclination of 20 ° -40 ° from the vertical to its center, on the lower surface of the base of the block, there is a network of intersecting rows of grooves parallel to the sides of the base, with a grid pitch of 35-45 mm and a width of each furrow of 5-10 mm, and gas-conducting channels are made in the form of a vertical holes with a diameter of 0.10-0.25 mm in the entire height of the block, arranged in increments of 1.0-2.0 mm in at least one row above some of the grooves of the base of the block.

The specified embodiment of the purge unit allows the purge of liquid metal with gas with high throughput while providing a loose flow of the introduced gas, i.e. with effective fine-bubble mode.

The formula for a useful model of a purge block has one independent and five dependent points, which describe particular cases of its execution, one of which, for example, indicates that when vertical capillary holes are located above some of the grooves of the base of the block in several rows, the distance between the rows should be at least 1.0 mm.

A device for purging liquid metal with gas in a bucket generally comprises a gas-permeable module integrated into the working layer of the lining of the bottom of the bucket, consisting of at least one section of at least one purge block described above, mounted on a metal tray with a maximum height of vertical sides of 50 mm connected to the pipe for supplying gas, and in option 1 of the device, each section of the purge units has its own pipe for supplying gas, to each of which is connected from the outside to a bucket is a receiver with a non-return valve, and in option 2, all sections of the purge units are connected via pipes to the reinforcing layer of the lining of the bottom of the bucket for supplying gas with one pipe and a receiver with a non-return valve.

The formula for a useful model of a metal purge device has two independent points (options) and eight dependent points.

So, in one of the particular cases of execution, it is indicated that the upper part of the purge blocks protrudes above the surface of the working layer of the lining of the bottom of the bucket by 30-100 mm, and in other particular cases the optimal layout of sections of the purge blocks in the bucket is described.

Description

A group of utility models relates to ferrous metallurgy, in particular to devices for treating liquid metal with gas in a ladle.

The ladle refinement of liquid metal to the required condition in various ways has firmly taken its place in the technological chain for the production of high-quality steels. The hydrodynamics of the metal-slag system has a decisive role in the removal of non-metallic inclusions during purging of steel with an inert gas.

In technically developed countries, starting in 1949, work is underway to study the influence of the hydrodynamic conditions of the gas flow on technological and quality indicators. When researching the processes occurring during the passage of gas flows through a liquid and analyzing the results obtained, a regularity was established: the degree of use of the purged gas mainly depends on the size of the surface and the time of contact of the gas with the liquid. It was established that, ideally, the gas flow should consist of small non-interacting bubbles. The experiments showed that in the case of a uniform distribution of gas over the entire volume of the melt in the form of bubbles with a radius of up to 1.0 cm, at its commonly used costs, more than double flotation cleaning of steel from inclusions of all fractions is possible.

The advantage of the melt blowing technology in the fine bubble mode is so obvious that, since the late 60s of the 20th century, repeated attempts have been made to constructively implement it.

The research results allow us to make an unambiguous conclusion: not only the total amount of gas consumed, but also the method of its input affects the efficiency of metal purging with gases. So for the effective removal of non-metallic inclusions, the purge of liquid metal, it is necessary to produce dispersed.

Based on these provisions, various constructive solutions were proposed for introducing gas into a liquid metal with the aim of processing it out of furnace. With all the variety of structural external differences of these devices, they all solved the same problems: increasing the gas-liquid contact area, increasing the safety and reliability of the process.

The earliest methods consisted of introducing gas through a false stopper installed in the bucket or a special stand with a submersible lined lance (for example, Aut. St. .. USSR No. 632734 for 1978, Aut. St. USSR No. 648120 for 1979. )

In these devices, gas is supplied through a central metal pipe protected by refractory tubes (coils), and is blown into the metal through an end porous block or nozzle.

All devices of this type (submersible tuyeres with nozzles) have one main drawback - extremely low efficiency due to the limited volume of the processed melt and gas supply not to the lower volume of the bucket, but at a distance of 0.5-1.0 m from the bottom, which leads to the fact that the melt is processed only in the near-tuft volume.

In order to increase the efficiency of such blowing devices, designs have been proposed that operate on the principle of an airlift pump (e.g. Aut. St. USSR No. 401725, 1971, Aut. St. USSR No. 523941, 1976)

Airlift pumps operate reliably in cold environments, and when working with molten metal, the structural strength of such devices is extremely low due to thermal shocks that occur when they are immersed and removed from liquid metal. Circulation in a limited space leads to accelerated erosion of the refractory (wear of the working surfaces) after each purge and contamination of the liquid metal with non-metallic inclusions. In addition, with intensive drilling of metal with slag, exposure of the metal mirror leads to the development of the secondary oxidation process and loss of melt temperature.

From the point of view of hydrodynamics and ease of maintenance, the installation of purge devices in the bottom of the bucket is more technologically advanced. In this case, the gas flow, rising from the bottom surface, interacts with the bottom volumes of the liquid metal. It is this fact that led to the widespread use of purge devices of this type.

The simplest, at first glance, is the installation of tubular inserts in a slide glass (for example, Aut. St. USSR No. 1232371 for 1986 or Aut.St. USSR No. 1373469 for 1988). In our country, purging through a slide gate began to be introduced in 1983. The practice of using such a design has shown rather low efficiency and unreliability. There are cases of metal breakthrough, which leads to emergency situations during casting. The gas flow rate provided by the design of such a device is clearly insufficient for a significant refinement of steel and, in fact, does not justify itself. An increase in gas flow leads to the formation of a flare regime, a highly developed breaker on the metal mirror and splashes from the ladle of liquid slag and steel.

Also noteworthy is the use of liquid metal blowing through gas-permeable seams of the lining of the bottom of the bucket, in which the gas flow has the form of individual loops consisting of bubbles with a diameter of 0.5-1.0 cm (for example, Autost. St. USSR No. 452428 for 1973)

However, in this case, gas passes between the masonry and the casing due to the noticeable gas permeability of the mortar on which the bricks are laid. All this is compounded by high ferrostatic pressure, which

prevents the escape of gas at the vertical seams of the working layer. So, with a metal filling height of about 3 meters, the ferrostatic pressure is 4.0 atm. Given the necessary 1.5-2.0 atm. to overcome the resistance to gas movement through the pores of the seams, the final pressure that is supplied under the lining of the bottom is 6.0 atmospheres. At this pressure, uncontrolled gas losses are inevitable. Thus, with the obvious simplicity of such a gas injection, its introduction encountered significant difficulties.

A more complex version is proposed in Avt.sv. USSR No. 590081 for 1978, where porous blocks are laid on the reinforcing layer, and the working layer is made with porous seams. But in this device, unfortunately, the design of the gas supply to each of the blocks is not indicated.

The most successful way of supplying gas to the porous seams of the lining of the bottom of the bucket is proposed in Auth. USSR No. 5778160 for 1977. This design is a steel pouring ladle, on the metal bottom of which a layer of granular material is laid, for example, dolomite crushed stone, fireclay, etc. This layer performs two functions: the first is thermal insulation and alignment, the second is the distribution of gas under the masonry. Gas is supplied via a nozzle directly to the granular layer. The gas permeability of the granulate is significantly higher than the porous mass from which the lining of the bottom is made, therefore, the gas pressure under the masonry is evenly distributed. In addition, the absence of a cavity under the lining of the bottom allows not only to reduce heat loss, but also to increase the operational reliability of the bucket. But the granular layer, 60-100 mm thick, tends to shift during tilting of the bucket, which degrades its performance.

More promising and effective are porous plugs and blocks installed in the bottom of the bucket, the use of which is described, for example, in the brochure “Drain-line blowing of the melt in the fine bubble mode," by B. Zhivchenko ed. Don GASA, Donetsk, 2004, 38 p.

One of the advantages of such devices is that purging can be carried out already after filling the bucket, that is, there is no need to purge an empty bucket, the next advantage is higher operational reliability and safety of porous plugs and blocks, since they are an integral part of the bottom lining, therefore, there are no through channels. In addition, gas is introduced into the melt in the bubble mode, the operation of the slide gate is not disturbed.

The use of porous plugs and blocks has found quite wide application. They are made from high alumina or magnesite powders of a certain fraction by pressing and calcining at temperatures (1600-1700) ° C. In this case, the surface of the grains is melted and welded. The inserts have the shape of a truncated cone with a slope forming up to 15 °. They are inserted into the cassettes, the gap is clogged with refractory clay. For mounting

cassettes in the bottom cut out a hole forming a hatch. The cassette is welded around the perimeter of the hatch, and the hatch, after installing the cork, is closed by a lid. Similar devices were widely used in 70 ... 80 years. at the metallurgical enterprises of the USSR. The advantage of such plants is the ability to quickly change porous inserts. DIDIER (an advertising product of DIDIER information 1997) offers a similar device that is convenient to use, but more difficult to maintain and repair.

The advantage of such plants is the ability to quickly change porous inserts. A major drawback of this design is the need to violate the integrity of the armor of the bottom of the bucket.

To eliminate this drawback, purge devices have been proposed, consisting of porous plugs enclosed in cassettes with a welded nozzle. One of the options for this design is described in the invention "Device for purging molten metal in a ladle" by Auth. USSR No. 648343, published September 25, 1979, In 22 D 41/00, which is selected as a prototype of the claimed device. A similar design of a device for purging metal with gas is shown in the advertising product of the German company DIDIER (image is shown in Fig. 8).

Such plugs are installed autonomously without violating the integrity of the armor. When reinstalling such a cork, it is necessary to cool the bucket to remove the worn cork and re-fill with gas-tight clay around the cork.

The throughput of such a device with a gas-permeable plug is much higher than that of the tube, however, the gas flow rate is limited by the behavior of the metal mirror, since the appearance of a breaker leads to a rupture of the slag coating with all the ensuing negative consequences in the form of the development of secondary oxidation processes and the cessation of the removal of non-metallic inclusions, capture of slag and its transfer to the melt volume.

In order to loosen the gas stream, the German company DIDIER has proposed a series of purge plugs described in the above-mentioned brochure Zhivchenko B.C. “Loopback purge of the melt in the fine bubble mode”, ed. Don GASA, Donetsk, 2004, p. 23.

The design of such plugs is selected as a prototype of the claimed purge unit. They are purge plugs with dense refractory and gas-conducting channels of a slot or capillary shape, located at some intervals between each other (in increments).

These spaces provide gas flow autonomy. However, the throughput of such traffic jams, according to the company, is not more than 1 m3 / min. In addition, at the end of the casting, the supercooled metal is frozen on the bottom surface, including on the working surfaces of the porous plugs with the formation of nastily, reducing their gas permeability. When cleaning the working surface of the purge devices, their severe destruction occurs. Often the resistance of one cork is equal to one heat.

The objective of the claimed group of utility models - a device for purging metal with gas and the purge unit used in it, is to increase their efficiency and reliability.

The problem is solved due to the design parameters of the purge unit, as well as the size and location of the capillary-shaped gas-conducting channels inside the unit.

The inventive purge unit made of dense refractory with gas-conducting channels of capillary shape, is based on the shape of a rectangular parallelepiped, in which the upper part of at least one side surface is inclined 20 ° -40 ° from the vertical to its center, and the upper beveled part the block is 50 ± 10% of its total height. At the same time, a network of intersecting rows of grooves parallel to the sides of the base is located on the lower surface of the base of the block, with a pitch of this network of 35-45 mm and a width of each furrow of 5-10 mm. Moreover, the gas-conducting channels are made in the form of vertical capillary holes with a diameter of 0.10-0.25 mm in the entire height of the block, which are arranged in increments of 1.0-2.0 mm at least in one row above some of the grooves of the base of the block.

Depending on the size of the steel pouring ladle and the specific tasks of purging the metal with gas (mixing, refining, etc.), the purging units can be combined into working sections. In this case, the rectangular lower half of the purge block gives the maximum abutment of the blocks when they are combined into a working section.

At the same time, inside the section, the purge blocks adjoin each other with a different number of sides:

- on one side (blocks in a section of two blocks, as well as extreme blocks in a section where the blocks are located in one row of more than two blocks);

- by two sides (middle blocks in the section where the blocks are located in one row, consisting of more than two blocks; extreme blocks in the section where the blocks are located in two rows, consisting of more than two blocks in a row, as well as extreme corner blocks in sections where the blocks are located in more than two rows, each of which consists of more than two blocks);

- by three sides (middle blocks in the section where the blocks are arranged in two rows, each of which consists of more than two blocks, and also not corner corner blocks in the section where the blocks are located in more than two rows, each of which consists of more than of two blocks);

- four sides (internal blocks in the section where the blocks are located in more than two rows, each of which consists of more than two blocks).

The chamfered side surface or surfaces (one, two, three or all four) of the upper part of the purge unit acts as a lock, as due to its presence, when several blocks are combined into a section, after it is installed in the bucket and filled with refractory material, it fills precisely the space formed between the bevels of the side surfaces of the blocks, which ensures the integrity of the section as a whole.

Moreover, it was experimentally established that the best option is when the height of the upper beveled part of the block is 50% of its total height, with a tolerance of ± 10% from that indicated. It was also experimentally established that the optimal angle of inclination lies in the range of 20 ° -40 ° from the vertical. The indicated parameters provide on the one hand the solidity of the section, and on the other, sufficient strength and reliability of the blocks.

The implementation of gas-conducting channels in the form of vertical capillary holes with a diameter of 0.10-0.25 mm in the entire block height allows, on the one hand, to provide a finely bubble mode when blowing metal with gas, and on the other hand, does not allow metal to penetrate into the capillary holes of gas-conducting channels , i.e. - interferes with their noticeability.

The implementation of the vertical capillary openings of the gas-conducting channels in at least one row with a pitch of 1.0-2.0 mm makes it possible to provide a gas purge mode in which the flows of its bubbles do not merge with each other, i.e. autonomous.

The presence on the lower surface of the network block of intersecting rows of grooves parallel to the sides of the base, some of which have vertical gas-conducting capillary channels above and along them, helps to quickly supply gas to all gas-conducting channels supplied to purge the metal, which is evenly distributed with these furrows throughout the base of the block.

In addition, the grooves are used as openings for fixing the slings when mounting the blowing units in the bucket using a crane beam or hoist.

Moreover, it was experimentally established that the optimal pitch of the network of furrows of the base of the block is 35-45 mm, and the width of each furrow is 5-10 mm. With a smaller step, an undesirable weakening of the block occurs, its strength deteriorates, and with a larger step, the gas transmission capacity of the block decreases and the metal purge efficiency decreases.

Thus, the design of the inventive unit allows purging of liquid metal with gas with high efficiency, i.e. with high throughput while providing a loosened stream of introduced gas, i.e. with effective shallow bubble mode.

In the particular case of the purge block, the vertical capillary holes above some of the grooves of the base of the block are arranged in rows at a distance between them of at least 1.0 mm.

The arrangement of vertical gas-conducting capillary channels over some of the furrows in several rows increases the gas transmission capacity of the block, and observing the indicated distance allows you to maintain a mode in which linear regions of small bubbles remain autonomous rather than merge into a torch.

In the particular case of the purge block, vertical capillary holes are located above each furrow along the greater side of the base of the block.

With this arrangement of vertical gas-conducting capillary channels, the design of the purge unit is technologically advanced and allows for an efficient fine-bubble mode when metal is purged.

In the particular case of the purge block, the network of intersecting rows of grooves is indented by one step from the edges of the base, not located under the partially chamfered side surfaces of the block.

It was experimentally established that the implementation of a network of grooves indented from the edges of the base increases the strength of the base of the purge unit, protecting it from chips when mounted in a bucket. But when combining blocks into a section, the furrows at the edges with which the block adjoins other blocks (surfaces with bevels) must be interconnected and form uniform channels for supplying gas to all blocks of the section, therefore, indents can only be from the edges of the base, located not under beveled side surfaces of the block.

In the particular case of the purge block, the vertical capillary holes above each furrow along the greater side of the base of the block are arranged in two rows at a distance of at least 1.0 mm from each other and are made only facing its upper horizontal platform.

With this arrangement of vertical gas-conducting capillary channels in two rows, the design of the purge unit is the most technologically advanced and provides high gas throughput with a shallow bubble mode of metal purge. In addition, vertical capillary openings extend only to the horizontal upper surface of the block and do not extend to the beveled side surfaces, which are filled with gas-tight concrete in working condition and do not work.

In the particular case of the execution of the purge block, the furrows in the base of the block are made with a rounded arch profile.

This implementation of the furrows is optimal, because maximizes their integrity during the installation of purge units, as well as

protects from the appearance of chips in the operating mode under the influence of high temperatures in the bucket.

The task of increasing the efficiency and reliability of the device for purging liquid metal with gas in the bucket is solved due to the fact that it contains a gas-permeable module integrated in the working layer of the lining of the bottom of the bucket, installed in a metal cassette connected to the gas supply pipe.

In this case, the gas-permeable module consists of at least one section in which several or one of the purge units described above are combined. The metal cassette is made in the form of a metal pan with a maximum height of vertical sides of 50 mm for each section of the purge blocks.

Moreover, in one embodiment of the device, each section of the purge blocks has its own pipe for supplying gas with a receiver with a check valve connected to it from the outside of the bucket, and in another embodiment, all sections of the purge blocks using pipes located inside the reinforcing layer lining of the bottom of the bucket, connected to one pipe for supplying gas, which from the outside of the bucket is connected to the receiver with a check valve.

The inventive device uses the above-described purge blocks of dense refractory in the form of a rectangular parallelepiped, in which the upper part of at least one side surface with half the block height is made beveled, and the gas-conducting vertical capillary channels are arranged at the entire height of the block, arranged in rows in a certain step some distance from each other over some of the furrows of the base of the block.

Depending on the size of the steel pouring ladle and the specific tasks of purging the metal with gas (to ensure the mixing mode, refining, etc.), the blowing units are combined into sections. Moreover, inside the section, depending on its size and the location of the blocks, they adjoin each other with a different number of sides: one, two, three or all four. When pouring sections from the purge blocks, refractory material fills the space between the bevels of the side surfaces of the blocks, which ensures the integrity of the section as a whole.

The blowing units, combined in sections, are installed on a cartridge made in the form of a metal tray with vertically bent low sides. At the same time, it was experimentally established that the maximum height of the vertical sides is 50 mm, otherwise due to high temperatures in the upper part of the working layer of the ladle lining, the metal sides burn out from above and molten metal flows into the formed holes, destroying the lining.

In the inventive device, a pipe for supplying gas from the outside of the bucket is connected to the receiver with a check valve. At the beginning of the gas supply, under the influence of its pressure, the receiver valve opens and the gas through the pipe enters the sections from the purge units. After the gas supply is stopped, the residual gas remains in the receiver, which is held by a closed check valve, thereby creating a gas plug in the capillaries of the gas-conducting vertical channels of the blowing units and protecting them from metal suction inside the channels. Thus, this embodiment of the device protects the gas-permeable vertical capillary channels of the purge units from being noticeable.

When the device is implemented in the first embodiment, when each section of the purge units has its own gas supply pipe with a receiver with a check valve connected to each of them, the gas system is routed outside the bucket, which simplifies installation of the system. However, the installation of several gas supply pipes that violate the integrity of the bucket bottom armor affects its reliability. Therefore, the device in the execution according to the first embodiment is used with a small number of sections from the purge units: one, two or three.

When the device is implemented in the second embodiment, all sections of the purge blocks are connected to one pipe for supplying gas using pipes located inside the reinforcing layer of the lining of the bottom of the bucket, i.e. The gas system is routed inside the bucket. The installation of gas ducts inside the lining complicates the work of masons, affects the quality and reliability of the lining. But, since this requires only one pipe that violates the integrity of the armor of the bucket bottom for supplying gas, this positively affects reliability in general, and therefore the device in the execution according to the second embodiment is used for the number of three or more sections from the purge units.

Both versions of the inventive device allow you to place sections of the purge units in any desired location on the bottom of the bucket with the formation of the necessary configuration and the area of the gas-permeable module depending on the capacity of the bucket and the requirements for the purge mode of individual sections of metal or its entire volume. Moreover, the design of the device provides high reliability and operational efficiency.

In the particular case of a device for blowing liquid metal with gas, the upper surface of the blowdown blocks of the gas-permeable module described above, after they are installed in sections in a bucket and filled with refractory concrete, protrudes 30-100 mm above the surface of the working layer of the bottom lining. It was experimentally established that these protrusions of the purge blocks above the lining can significantly extend the life of the device, i.e. the specified implementation increases the wear resistance of the device. In addition, the sloping side surface (one, two, three, or all four) of the upper lining of the bucket

parts of the purge blocks, allowing the residual metal to slide along it / him during the discharge, prevents the unit from being swept over from above.

In the particular case of a device for blowing liquid metal with gas, sections of the blowing units of the gas-permeable module described above are located anywhere in the bucket, with the exception of a sector with a central angle of 60-90 °, in the center of which there is a "battlefield" (the place where the metal is fed into the bucket ) It has been experimentally established that in the indicated sector around the place where the metal is fed into the ladle, the maximum possible wear of the blowing units is observed, and their placement outside this sector increases the wear resistance of the claimed device.

In the particular case of the execution of the device for purging liquid metal with gas, at least two sections of the above-described purging blocks of the gas-permeable module are installed symmetrically on different sides from the "battle" place (the place of metal supply to the ladle) at a distance from the center of the bucket to the center of the section, equal to 0 , 5-0.7 radius of the bucket.

It was experimentally established that the indicated arrangement of sections from the purge blocks is optimal to ensure uniform purging of metal in the bucket.

In the particular case of a device for blowing liquid metal with gas, each of the two sections of the blowing units of the gas-permeable module described above is installed so that the radius of the bucket passing through the center of the section perpendicular to its long side forms an angle with a radius passing through the center of the slaughterhouse 135 °.

It was experimentally established that the indicated arrangement of sections from the purge blocks is optimal to ensure the mixing and refining of liquid metal in the ladle.

The design of the inventive purge unit and device for purging metal gas in the bucket is illustrated by the following drawings:

figure 1 presents the purge block (types) in the General case of its execution with one beveled side surface and the location of gas-permeable vertical capillary channels above the grooves of the base in one row;

figure 2 presents the purge block (types) in the particular case of its execution with all beveled side surfaces and the location of gas-permeable vertical capillary channels above the grooves of the base in three rows;

figure 3 presents views of the purge unit in the particular case of its execution with two beveled side surfaces,

the arrangement of gas-permeable vertical capillary channels over each furrow along the long side of the base in two rows, extending only to the upper horizontal surface of the block, with indentations of the furrows in the base from the edges;

figure 4 presents the types of sections from a different number of purge blocks of a gas-permeable module of the inventive device;

figure 5 presents version 1 of the device for purging metal gas in the bucket, when each section of the purge blocks has its own pipe for supplying gas and a receiver with a check valve;

Fig. 6 shows an embodiment 2 of a device for purging metal, when all sections of the purging units are connected by a pipe system inside the reinforcing layer of the lining of the bottom of the bucket for supplying gas with one pipe and a receiver with a check valve;

figure 7 shows the layout of the sections of the gas-permeable module in the bucket in particular cases of execution of the inventive device:

a) with the location of the sections of the purge blocks anywhere in the bucket, with the exception of the sector with a central angle of 60-90 °, in the center of which is located the "fighting" place;

b) with the location of at least two sections of the purge units symmetrically on different sides of the “slaughter” place at a distance from the center of the bucket, equal to 0.5-0.7 radius of the bucket;

c) with the location of each of the two sections of the blowing units in such a way that the radius of the bucket passing through the center of the section perpendicular to its long side forms an angle of 135 ° with the radius passing through the center of the “slaughter” site;

on Fig presents prototypes of the claimed technical solutions:

a) a purge unit;

b) devices for purging metal gas in the bucket.

The inventive design of the purge unit in General and in particular cases of execution (Fig.1, 2, 3) contains the following elements.

The purge unit 1, made of a dense refractory with gas-conducting channels of capillary shape, having basically a rectangular parallelepiped, in which the upper part of at least one side surface 2 with half the block height is made with an inclination of 20 ° -40 ° from the vertical to the center . At the same time, on the lower surface of the base of the block there is a network of intersecting rows of grooves 3 parallel to the sides of the base, with a pitch of this network of 35-45 mm and a width of each furrow of 5-10 mm. Moreover, the gas-conducting channels 4 are made in the form of vertical capillary holes with a diameter of 0.10-0.25 mm in full height

purge block, which are arranged in increments of 1.0-2.0 mm in one or more rows (with a distance between rows of at least 1.0 mm) above some (depending on version) of the furrows 3 of the base of the block.

In the particular case of execution (Figure 3), the network of intersecting rows of grooves 3 is indented one step from the base edges located not under partially chamfered side surfaces of the block, vertical capillary holes are made facing only the upper horizontal platform of the block, and the furrows in the base of the block is made with a rounded arch profile.

When combining the purge blocks in the section (Figure 4) of the required size and configuration, the blocks, depending on their location inside the section, adjoin each other with a different number of sides: one, two, three or all four.

The inventive device for purging liquid metal with gas in a bucket in both variants of its implementation (Figs. 5, 6) comprises a gas-permeable module 5 integrated into the working layer of the lining of the bottom of the bucket, consisting of at least one section in which several or one of the purging is combined blocks 1 described above (FIG. 1) mounted on a metal tray 6 with a maximum height of vertical sides of 50 mm, connected to a pipe 7 for supplying gas and a receiver 8 connected to it with a check valve.

Moreover, in option 1 of the claimed device (Figure 5), each section of the purge units 1 has its own pipe 7 for supplying gas with a receiver with a check valve 8 connected to it from the outside of the bucket.

In embodiment 2 of the inventive device (FIG. 6), all sections from the purge units 1 are connected by pipes located inside the reinforcing layer of the lining of the bottom of the bucket to one pipe 7 for supplying gas, which is connected to the receiver 8 with a check valve from the outside of the bucket.

In the particular case of the execution of the claimed device, the upper surface of the purge blocks 1 protrudes above the surface of the working layer of the lining of the bottom of the bucket by 30-100 mm, as shown in Fig.6.

In other particular cases, the execution of the device with a different arrangement of sections from the purge blocks 1 of the gas-permeable module 5 in the bucket, shown in Fig.7, the inventive device contains the same structural elements as in the general case.

The inventive device for purging liquid metal with gas in a bucket (FIGS. 5, 6), as part of which the inventive purging unit is used in all cases of its execution (FIGS. 1, 2, 3) from a dense refractory having the shape of a rectangular parallelepiped 1, in which the upper part of at least one side surface of the block with a half height has a bevel 2, with gas-conducting vertical channels in full height

block capillary form 4, arranged in rows along the grooves 3 in the base, in the General case, works as follows.

Depending on the specific tasks of metal purging with gas (mixing, refining, etc.) and the size of the steel pouring ladle for the gas-permeable module 5, the necessary and sufficient number of sections from the blowing units 1, the number in each section of the blowing blocks, and also the layout scheme are selected in the bucket. After this, a gas-permeable module 5 is formed, for which, in accordance with the selected scheme, metal pallets 6 with sides are built into the working layer of the lining of the bottom of the bucket. Pipes 6 are connected to pallets 6 for supplying gas to the device, ending with a pipe 7 facing the outside of the bucket, with a receiver with a check valve 8 connected to it. Blowing blocks 1 using slings threaded into the openings of grooves 3 at the base of the blocks, with a crane beam or a hoist is mounted on the corresponding metal pallets 6, forming sections in which due to the rectangular shape of the lower half of the blowing units 1 their maximum contact with each other is ensured. Then, the gas-permeable module 5 thus formed is filled with refractory material, which fills the space between the bevels 2 of the adjacent side surfaces of the blowing units 1 in the working sections, which ensures their solidity and strength.

After the liquid metal begins to flow into the bucket, gas for purging it under pressure through the open valve of the receiver 8 and pipe 7 is fed to the sections of the gas-permeable module 5, namely, to the space between the surface of the metal pallets 6 and the arches of the furrows 3 of the base of the purge blocks 1.

Moreover, in option 1 of the inventive device (Figure 5), where each section of the purge units 1 has its own pipe 7 with a receiver connected to the check valve 8, gas is supplied and supplied through each of the existing pipes 7.

And in option 2 of the inventive device (Fig. 6), where all sections from the purge units 1 are connected via a pipe network inside the reinforcing layer of the lining of the bottom of the bucket to one pipe 7 with a receiver connected to it with a check valve 8, gas is supplied and supplied through this one pipe 7.

Due to the presence of grooves 3 on the lower surface of the purge blocks 1, the gas supplied to the metal is quickly and evenly distributed over the entire base of the block and is supplied to all gas-conducting vertical channels of capillary shape 4 located in rows along the grooves 3 over the entire height of the block. Further, the gas under the influence of pressure passes through the capillary holes of the gas-conducting vertical channels of the blowing units 1 and enters the liquid metal. The design parameters of the purge unit, the diameter of the holes of the gas-conducting vertical channels, the distances between them are selected so that the gas

enters the liquid metal in the form of a loosened stream of small autonomous bubbles, mixing the metal, refining it, etc. In addition, the selected dimensions prevent noticeable purge blocks 1, because metal does not penetrate back into the capillary openings of the gas-conducting channels.

At the end of the metal purge and the gas supply to the device is stopped, the residual gas remains in the receiver 8, which is held by its check valve, thereby creating a gas plug in the capillaries of the gas-conducting vertical channels 4 of the blowing units 1 and protecting them from metal “suction” inside the channels 4, those. protecting the gas-permeable vertical capillary channels 4 of the purge blocks 1 from being obscured.

Replacement of purge blocks is carried out during overhaul of the working layer of the lining of the bucket.

In the particular case of the execution of the claimed device, when the purge blocks 1 protrude above the surface of the working layer of the lining of the bottom of the bucket (Fig.6), after the metal is drained from the bucket, the residual metal slides along the bevels of the side surfaces of the blocks 1, preventing the purge blocks from being visible from above.

In other particular cases, the execution of the device with a different arrangement in the bucket of sections from the purge units 1 of the gas-permeable module 5, shown in Fig.7, the inventive device works in the same way as in the general case.

To implement a group of utility models — a purge unit and a device for purging metal with gas, both in the general case and in particular cases of execution, known technological processes and materials can be used.

Example 1. At the Severstal plant, when smelting steel, blowing blocks of INTOVAL SF85-10 / 11 high-alumina refractory concrete in the form of a bar with a base size of 400 × 400 mm and a height of 350 mm and having bevels of two opposite side walls were tested and worked well. surfaces at an angle of 30 ° from half the height. At the base of the blocks, a network was made of rows running parallel to its sides and intersecting rows of furrows with a pitch of 40 mm, a width of each furrow of 10 mm and a rounded arch profile (Fig. 3). At the same time, gas-conducting vertical capillary channels in the entire height of the purge blocks with a hole diameter of 0.19 mm were located above each furrow along the side of the base without bevels with a pitch of 2.0 mm, made in two rows (Fig. 3) with a row distance of 2 , 0 mm.

These purge units were tested when purging steel in a bucket with a diameter of 3600 mm. The lining of the bottom of the bucket had two layers: reinforcing - from granulate (for example, broken brick) and two layers of fireclay brick, with a total height of 200 mm; and a working layer 300 mm high - from high-alumina refractory concrete of the INTOVAL SF85-10 / II brand.

The device for purging metal with gas in this case was performed according to option 1 (figure 5) as follows. Two sections were built into the working layer of the lining of the bottom of the bucket, each of which consisted of 4 blowing units in a row (Fig. 4), and the sections were located at a distance of 0.7 radius of the bucket symmetrically on different sides of the “slaughter” place that the radius of the bucket passing through the center of the section perpendicular to its long side forms an angle of 135 ° with the radius passing through the center of the slaughterhouse (Fig. 7c). Sections of blowing units were installed on stainless steel trays with dimensions of 400 × 1600 mm with vertical sides of 50 mm. Each section had its own stainless steel pipe extending beyond the armor of the bucket, to each of which was connected a receiver with a check valve, used, for example, in an air filter of the CAMOZZI N104-F00 type. Steel was purged with neutral gas — argon under a pressure of 4–6 atm., Which was supplied from the gas distribution system via collector networks.

The use of these blocks and the device allowed to purge the metal in the bucket with an effective fine bubble mode while ensuring good performance.

Example 2. At the Severstal plant for refining smelted steel under the conditions described in example 1, one section of 2 blowing units was used, having, starting from 60% of the total height, one bevel on the side surfaces at an angle of 20 ° from the vertical. At the base of the blocks, a network was made of rows running parallel to its sides and intersecting rows of furrows with a pitch of 35 mm, a width of each furrow of 5 mm and a triangular contour of the arch of furrows (Fig. 1).

At the same time, gas-conducting vertical capillary channels in the entire height of the purge blocks with a hole diameter of 0.25 mm were located above each of the grooves of the base in a single row (Fig. 1) and made in increments of 1.0 mm.

A section of these purge blocks was mounted on a stainless steel pallet with dimensions of 400 × 800 mm with vertical sides of 40 mm and used under the conditions described in example 1, and the device for purging metal with gas was mounted in the same way as described in example 1, and a section of two purge units was located in the center of the bucket (figa).

The use of these blocks and devices allowed efficient refining of the metal when it was purged in the bucket with inert gas in a shallow bubble mode without disruption to the "flare" mode.

Claims (16)

1. A purge block of dense refractory with vertical gas-conducting channels of capillary shape, characterized in that the block is made in the form of a rectangular parallelepiped, in which the upper part of at least one side surface, comprising 50 ± 10% of the total block height, is made with an inclination of 20-40 ° from the vertical to its center, and on the lower surface of the base of the block there is a network of intersecting rows of grooves parallel to the sides of the base, with a grid pitch of 35-45 mm and a width of each furrow of 5-10 mm, and gas-conducting channels filled in the form of vertical to the entire height of the block capillary holes with a diameter of 0.10-0.25 mm, which are arranged in increments of 1.0-2.0 mm in at least one row above some of the grooves of the base of the block. 2. The purge block according to claim 1, characterized in that the vertical capillary holes above some of the grooves of the base of the block are arranged in rows at a distance of at least 1.0 mm from each other. 3. The purge block according to claim 1, characterized in that the vertical capillary holes are located above each furrow along the greater side of the base of the block. 4. The purge unit according to claims 1 to 3, characterized in that the network of intersecting rows of furrows is indented by one step of the network from the edges of the base, not located under partially chamfered side surfaces. 5. The purge block according to claim 1, characterized in that the vertical capillary holes above each furrow along the greater side of the base of the block are arranged in two rows at a distance of at least 1.0 mm from each other and are made only facing the upper horizontal platform of the block. 6. The purge block according to claim 1, characterized in that the grooves in the base of the block are made with a rounded arch profile. 7. A device for purging liquid metal with gas in a bucket (option 1), comprising a gas-permeable module integrated in the working layer of the lining of the bottom of the bucket installed in a metal cassette connected to a gas supply pipe, characterized in that the gas-permeable module contains at least one section of at least one purge unit according to claim 1, the metal cartridge is made in the form of a pallet with a maximum height of vertical sides of 50 mm, and each section of the purge units has its own nozzle for supplying ha and, each of which is connected with the outside of the bucket with nonreturn valve. 8. A device for purging liquid metal with gas in a bucket according to claim 7, characterized in that the upper part of the purging blocks according to claim 1 of the gas-permeable module, after filling it with refractory material, protrudes 30-100 mm above the surface of the working layer of the lining of the bottom of the bucket. 9. A device for purging liquid metal with gas in a bucket according to claim 7, characterized in that the sections of the blowing blocks according to claim 1 are located anywhere in the bucket, except for the sector with a central angle of 60-90 °, in the center of which is located slaughter "place (the place of supply of metal in the bucket). 10. A device for purging liquid metal with gas in a bucket according to claim 7, characterized in that at least two sections of the blowing units according to claim 1 are installed symmetrically on opposite sides of the “slaughter” place (the place of metal supply to the bucket) at a distance 0.5-0.7 radius of the bucket from its center to the center of the section. 11. A device for purging liquid metal with gas in a bucket according to claim 10, characterized in that each of the two sections of the blowing units according to claim 1 is installed so that the radius of the bucket passing through the center of the section is perpendicular to its long side, and with a radius passing through the center of the battlefield forms an angle of 135 °. 12. A device for purging liquid metal with gas in a bucket (option 2), comprising a gas-permeable module integrated in the working layer of the lining of the bottom of the bucket installed in a metal cassette connected to a gas supply pipe, characterized in that the gas-permeable module contains at least one section of at least one purge unit according to claim 1, the metal cartridge is made in the form of a pallet with a maximum height of vertical sides of 50 mm, and the pipe is connected from the outside of the bucket to the receiver with a reverse valve nom, and the pipes for supplying gas from the pipe to the sections of the purge blocks are located inside the reinforcing layer of the lining of the bottom of the bucket. 13. A device for purging liquid metal with gas in a bucket according to claim 12, characterized in that the upper part of the purging blocks according to claim 1 of the gas-permeable module protrudes 30-100 mm above the surface of the working layer of the lining of the bottom of the bucket after filling it with refractory material. 14. A device for purging liquid metal with gas in a bucket according to claim 12, characterized in that the sections of the blowing blocks according to claim 1 are located anywhere in the bucket, except for a sector with a central angle of 60-90 °, in the center of which is located slaughter "place (the place of supply of metal in the bucket). 15. A device for purging liquid metal with gas in a bucket according to claim 12, characterized in that at least two sections of the blowing units according to claim 1 are installed symmetrically on opposite sides of the “slaughter” place (the place of metal supply to the bucket) at a distance 0.5-0.7 radius of the bucket from its center to the center of the section. 16. A device for purging liquid metal with gas in a bucket according to claim 15, characterized in that each of the two sections of the blowing units according to claim 1 is installed so that the radius of the bucket passing through the center of the section is perpendicular to its long side, and with a radius passing through the center of the battlefield forms an angle of 135 °.