EA038416B1 - Plug for converter entrances - Google Patents

Abstract

Liquid steel 5 should flow through a hatch 4 of a converter 2 into a caster ladle 3, without capturing slag 6. To ensure that, the plug 1 is inserted with its body 8 into the hatch 4 using a rod or a similar applicator 17 and is fixed there. Fixation is achieved by that holding clips 15, 16, attached to the plug body 8 and fixed in or on the hatch 4 ensure that either an upper sheet 12 moves in the direction of a lower sheet 11, or the lower sheet 11 with a tube 13 moves in the direction of the upper sheet 12. Thus a protrucing section 14 of the tube 13 is arranged to prevent penetration of slug during the purging process. The simple and light-weight in design holding clips 15, 16 and 20, 21 are positioned in a way to allow or cause such movement processes. The plug body 8 is easy to handle due to its total weight and soft mass which is achieved among other things by admixing a blend of light bodies 10 and additional light bodies 28 to a clay mass 9.

Description

SUBSTANCE: invention relates to a plug for temporary clogging of a taphole of a tiltable converter containing a cylindrical deformable body made of a clay mixture, light bodies made of low-melting hydrocarbon compounds, a plasticizer and cellulose, as well as oil as a shaping aid, limiting the plug body from below, a lower sheet, limiting the plug body from above a top sheet and a pipe connecting both sheets, and the plug body is made with the possibility of being inserted into the taphole by means of an applicator and fixing therein, as well as being washed out of the taphole by means of liquid steel.

In the blast furnace process, first, iron is smelted from iron ore with the help of coke and lime. After being released into torpedo-shaped casting ladles, the cast iron is fed for further processing. The prepared pig iron is then melted into steel in a converter by blowing with oxygen, and for this, as a rule, additives such as scrap and alloying materials are used. These tiltable converters have an outlet or tap hole in the wall at a suitable location above the steel bath mirror for tapping liquid steel into the primary ladle. For emptying, the converter is tilted so that the steel flows through the tap hole into the ladle. Since a specific lighter slag of different viscosity always floats on the steel melt, it inevitably enters the taphole during the tilting process and, thus, in more or less large quantities, into the primary ladle. For numerous downstream metallurgical processes, the presence of an oxygen-rich and often rich in phosphorus or sulfur slag is a significant disadvantage. Therefore, there is a requirement to discharge converter steel as much as possible without slag into the primary ladle. A plug is known from EP 0635071, in which the top sheet is formed into a funnel-shaped channel that crosses the plug or its body and is adapted to receive a pulling grip acting on the top sheet. In this case, the plug is inserted into the converter outlet channel so that its top sheet approximately coincides with the inner side of the converter, and then it is installed by pulling out the gripper. The top sheet passes into a funnel-shaped channel that crosses the plug, so that the plug is actually fixed on the inside of the converter and not on its outer wall. If the plug is properly seated, the top sheet is baked, and neither slag nor other components can flow out through the tap hole, but only pure liquid steel. As a result of the contact between the molten steel, the top sheet and the funnel-shaped channel or the tube forming it are partially melted, whereby the steel can flow in a targeted manner into the submerged casting ladle. Such a plug consists of refractory material, light bodies of low-melting hydrocarbon compounds, plasticizer, cellulose and oil. Depending on the size of the plug, it is difficult to handle the applicator or landing device. Depending on the residence time of the plug, the deformation in the taphole is also associated with problems, and the handling of the landing device requires a certain skill, since this additional device with a pulling grip has to be used again after the plug is seated.

The object of the invention is to provide a plug that, due to its material composition, could be easily deformed, without the mentioned landing device being inserted into the taphole and deformed in it.

This problem is solved, according to the invention, due to the fact that the cork body is made in the form of a soft mass with the possibility of high deformation and that it is given holding grips, which are fixed in the tap hole when the cork body is inserted and provide deformation of the cork body between the lower and upper sheets with the help of bar applicator.

According to the invention, the plug body is purposefully reduced in weight through the use of light bodies, and through the use of light bodies or additional light bodies, it is inserted into the taphole with a rod applicator, fixed there by simple advancement and sheet, or the top sheet is connected to the pipe, movement of both sheets in relation to each other is possible. The holding grips are fixed in the taphole, so that the body of the plug, which is already in the taphole, can no longer move further, but, on the contrary, is forcedly deformed.

According to an advantageous embodiment of the invention, it is provided that the holding jaws are fixed to the top sheet and that the bottom sheet is movable on the tube by means of a bar applicator. This ensures that the top sheet after fixing the retaining grips can no longer move further into the taphole, but, on the contrary, the bottom sheet located or located on the outer side of the converter moves further into the taphole, and it takes care that the cork body is deformed and fixed in notch.

In a further preferred embodiment, it is provided that the holding jaws are fixed to the top sheet, and the bottom sheet is connected to the pipe, and both can be moved by means of the bar applicator towards the top sheet. Thus, not only does the bottom sheet move towards the top sheet, but also the pipe, which then moves through the top sheet fixed by the holding grips and thus protrudes into the taphole in a short section. This additionally guarantees that the primary slag will not flow out through the pipe, and the slag coming out during the blowing process, depending on the composition, will be able to clog it, but, on the contrary, only reliably liquid

- 1 038416 steel, which, as already mentioned, dissolves both components of the plug, will in any case prevent the slag from flowing into the casting ladle.

In an improvement of this pipe connected to the bottom sheet, it is provided, according to one expedient variant, that the pipe can be moved by means of the applicator 5-15 cm, preferably 10 cm, beyond the top sheet into the inner space of the converter. This is a great advantage since the pipe can no longer be clogged by the splashing slag during the blowdown process, which leads to the clogging disadvantages described above.

Instead of joining, for example welding, the holding jaws with the topsheet, according to one expedient embodiment, it is provided that the two holding jaws connected to each other bear against the movable top sheet, enveloping the pipe from above. When moving the top sheet, the holding grips make sure that this is not possible if they are fixed on or in the taphole.

Instead of the described two holding jaws, it is also possible for two, three or four holding jaws, adjacent to the top sheet, to be connected to each other and to the topsheet, or, as described above, to simply abut also from above without this connection. Also, due to this, it is possible to prevent the movement of the top sheet, and with the help of the bottom sheet to cause the process of deformation of the cork body.

Depending on the design of the holding grips, it is possible to fix them in the taphole or on its cold outer edge.

Such fixation of the holding grips is guaranteed if they are made of reinforcing steel with a thickness of 6 mm, are bent at the lower free end, forming a hook, and with external dimensions of + 30-50 mm, mainly 40 mm, more than the circumference of the cork and 3-10 cm more than her body length. Thanks to these dimensions, first of all, it is guaranteed that the upper end, which is either stuck to the top sheet or lies on it, can fit snugly against the cork body, i.e. in any case, it cannot interfere with the entry into the taphole. If the plug body is inserted far enough into the tap hole, the lower free ends are hooked around the tap hole or around its cold outer edge, whereby the deformation process can then begin reliably. All this is done with a simple rod or applicator, so skill no longer plays a decisive role here.

The cork body consists of a soft mass named in claim 1 of the claims, in particular also a mineral oil used and light bodies, and according to one embodiment, in order to achieve a low total weight and the possibility of simple handling, mixing into the cork body is provided, in addition to these light bodies made of low-melting hydrocarbon compounds, additional light bodies in the form of mineral hollow balls consisting of foam glass. The cork body containing these different light bodies or additional light bodies is distinguished not only by its low total weight, but also by the fact that it can be optimally handled and thus easily inserted into the taphole. Finally, the contained mineral oil has an optimal shape-forming effect, as envisaged in the second preferred embodiment of the invention.

Such a plug contains, according to the invention, a body made from a mixture:

10-50 vol.% 10 'polystyrene granulate 0.3-5 mm,

5-30 vol.% Of additional hollow bodies in the form of foam glass 0.2-8 mm,

20-45 wt.% Of additional hollow bodies in the form of hollow aluminosilicate balls with a diameter of 0.11.5 mm,

15-70 wt% clay mixture of kaolinite, bentonite and clay 3-layer silicate,

0.5-3 wt.% Plasticizer,

0.1-2 wt% thinner,

0.1-2 wt% temporary binder,

0.1-5 wt.% Permanent binder and

2-8 vol.% Oils as a forming aid.

The use of glass hollow spheres is known, in principle, from document EP 2315859 B1, however, not in the material composition specified here and not together with polystyrene granulate 0.3-5 mm, which only in this composition gives the desired optimal weight reduction and, thereby , optimal ease of handling, and, in addition, together with the specific clay and bentonite used, it gives the mass the necessary softness.

Preferably, and according to the invention, it is also purposefully provided to mix the cork with said polystyrene granulate, however, in the form of 2-3 mm, while foam glass is introduced into the total mixture in the form of 0.2-0.5 mm, and aluminosilicate hollow balls are introduced in the form of 0.1-0.5 mm. Polystyrene should not be in the form of balls.

This shape changes the structure of polystyrene, which gives the cork together with the foam glass a high stability. The purposefully molded polystyrene gives the mass or mixture significantly better support than previously used styrofoam balls, since the new shape (coffee bean shape) creates a matrix similar to concrete mixture. This reliably achieves and maintains the required stability.

- 2 038416

In addition, according to the invention, the polystyrene granulate must be graphitized polystyrene, this graphitized styrofoam contributing to optimum mixing and adhesion of all components of the plug body. Such a plug ensures quick incorporation, ensures that the downloaded slag is always retained, also even while the converter is tilted, sits securely in the tap hole, does not sinter, and also that the channel is completely free at the time of discharge within 5-10 s, so so that the steel can flow out. The cork is well stored and lightweight, which makes it easier, in particular, to fit in the converter taphole. At the moment of the start of the discharge, the plug, due to the short delay of the steel, provides a sufficiently high bath of steel above the plug, so that vortices during the discharge can be reliably prevented. These negative vortices arise when the heights of the baths are less than 2.5 tap hole diameters, i.e. at the taphole 160 mm under a height of 400 mm. In the absence of a plug, vortices arise, which move in the bath to the surface through and, during tapping, capture the converter slag into a receiver or a casting ladle.

Further details and advantages of the subject matter of the invention are set forth in the following description of the accompanying drawings, in which a preferred embodiment is shown in the necessary detail.

The drawings show the following:

fig. 1 - tilted converter during the outflow of liquid steel;

fig. 2 - state of the art with a landing device;

fig. 3 - plug with four holding grips;

fig. 4 is a side view of a plug with an extended pipe;

fig. 5 - plug with two holding grips covering the pipe;

fig. 6 - a plug, in which the holding grips are connected to the top sheet and the bottom sheet, which moves on a pipe firmly connected to the top sheet;

fig. 7 is a section of the tap hole with an inserted plug and retaining grips fixed on the cold edge of the tap hole;

fig. 8 is a sectional view of the tap hole with an inserted plug and retaining grips fixed in the tap hole;

fig. 9 - lightweight styrofoam bodies made of graphite and made in the form of coffee beans.

FIG. 1 shows the converter 2 in section, and it can be seen that the outflowing molten steel 5 carries a layer of slag 6. The molten steel 5 flows through the taphole 4 into the casting ladle 3, which is already partially filled with molten steel 5 '. The plug 1 is not visible here, since it has already been washed out of the taphole 4 with liquid steel. Pos. 18 indicates the inner space of the converter, and pos. 24 denotes the cold edge of the tap hole 4. These reference numbers are explained in more detail below.

FIG. 2 shows a structure known from the prior art, in which the plug 1 with its entire body 8 is inserted into the taphole 4, in order to then be deformed by the landing device 22, for which, with the help of the landing device 22, 22 ', the lower 11 and upper 12 sheets move in relation to each other friend. As a result, the wall of the cork body 8 is pressed against the inner wall of the tap hole 4, as a result of which the tap hole 4 is effectively sealed. After removal of the seating device 22 and after a suitable tilt of the converter 2, molten steel can flow through the pipe 13, distributing in the casting ladle 3, as shown in FIG. 1.

FIG. 3 shows the execution of a plug 1, the body 8 of which is closed at the end inserted first into the taphole 4 by means of a top sheet 12. This top sheet 12 is connected to four holding jaws 15, 16, 20, 21, and these holding jaws 15, 16, 20, 21 their hooks 26, 26 'ensure that the plug body 8, after being inserted into the tap hole 4, is fixed there on the inner wall 7 or on the cold edge 24 of the tap hole. The bottom sheet 11 is not visible, but it connects the protruding pipe 13, the bottom sheet 11 and the top sheet 12.

FIG. 4 shows a variant in which only two holding jaws 15, 16 are used, having at the lower end, i.e. at the free end 25, hooks 26, 26 '. The holding jaws 15, 16 are firmly fixed on the upper sheet 12, while the movable mass 30 with the lower, unattached sheet 11 can move to the upper sheet 12 firmly connected to the pipe 13, so that the outer wall 27 of the cork body 8 can fit snugly against the inner wall 7 years old 4.

In this embodiment, the cork body 8, in addition to the clay mixture, contains polystyrene granules.

The plug in FIG. 5 differs in that here the two holding grips 15, 16 above the top sheet 12 are wound around the pipe 13 and connected to each other, so that it is possible to dispense with fixation, i.e. connection, with the topsheet 12. The pipe 13 here has a protruding section 14, which results from being pushed through the topsheet 12, forming the said protruding section 14, and this can occur when the body 8 of the plug is deformed. Due to this, the slag 6 cannot flow out through the pipe 13 and clog it, since it protrudes upward towards the hot side by about 10 cm, and no slag 6 forms in the pipe 13. Otherwise, in the case of a non-protruding pipe 13, it would easily clog during the blowing process. splashing slag, which would then cause problems when the converter is tilted and the liquid steel flows out 5.

FIG. 6 shows a variant in which the supports 15, 16 are connected to the top sheet 12, and

- 3 038416 pipe 13 together with the lower sheet 11 moves towards the upper sheet in order to fix the cork body 8 in the tap hole 4. This variant is characterized in that the cork body, in addition to the clay mixture 9 and light bodies 10, 10 ', also contains additional lungs bodies 28, 28 ', 28, which are placed in the mixture. The additional light bodies 28 'are composed of sodium / calcium silicate beads and the additional light bodies 28 are of aluminosilicate beads, so that, in general, the mixture described in claim 11 is formed. In this connection, it should also be pointed out that the light polystyrene granulate bodies consist of graphitized polystyrene and have the aforementioned coffee bean shape.

FIG. 7, 8 show a rod applicator 17, with which the plug body 8 can be inserted into the tap hole 4. Since the plug body 8 is equipped with the holding grips 15, 16 with hooks 26 shown in both figures, the plug body 8, upon reaching the position in FIG. 7, 8 is fixed in the taphole 4, whereby either the bottom sheet 11 moves towards the top sheet 12 or the top sheet 12 towards the bottom sheet 11. Also here in FIG. 8 shows the protruding section 14 and the accessory, not designated as the actual landing device 12, but the already mentioned bar applicator 17.

FIG. 9 depicts the aforementioned light bodies 10, 10 ', 10, with particular emphasis here on the shape of the coffee beans. In addition, these light bodies 10 are distinguished by their black color resulting from graphitization. It can be seen that the surface of these light bodies 10 is not completely flat, but has grooves, edges, etc., which facilitate fixation in the clay mixture 9.

FIG. 1 notch 4 is depicted with its both edges. Inside, i.e. on liquid steel 5, a warm edge 23 is visible, and the already mentioned cold edge is indicated by pos. 24. FIG. 5, the coverage of the ends of the holding grips 15, 16 is indicated by pos. 19.

Claims (14)

CLAIM 1. A plug for temporary clogging of the taphole (4) of the tilting converter (2), containing a cylindrical deformable body (8) made of a clay mixture (9), light bodies (10) made of low-melting hydrocarbon compounds, a plasticizer and cellulose, as well as oil as a shaping of auxiliary means, limiting the body (8) of the plug from below, the lower sheet (11), limiting the body (8) of the plug from above, the upper sheet (12) and the pipe (13) connecting both sheets, and the body (8) of the plug is made with the possibility of insertion by means of the applicator ( 17) into the taphole (4) and fixation in it, as well as washing out of the taphole (4) by means of liquid steel (5), characterized in that the body (8) of the plug is made in the form of a soft mass with the possibility of high deformation, while it is given holding grips (15, 16), which are made with the possibility of fixing on the taphole (4) when inserting the plug body (8) and ensuring deformation of the plug body (8) between the lower and upper sheets (11, 12) using a rod applicator (17) ... 2. A plug according to claim 1, characterized in that the retaining jaws (15, 16) are fixed on the top sheet (12), while the bottom sheet (11) is movable on the pipe (13) by means of a rod applicator (17). 3. Plug according to claim 1, characterized in that the retaining jaws (15, 16) are fixed on the upper sheet (12), the lower sheet (11) is connected to the pipe (13) and both are movable in the direction of the upper sheet (12 ) by means of a bar applicator (17). 4. The plug according to claim 3, characterized in that the pipe (13) is made with the ability to move by means of the applicator (17) by 5-15 cm, mainly by 10 cm, beyond the top sheet (12) in the direction of the inner space (18) of the converter ... 5. A plug according to claim 2, characterized in that the two holding grips (15, 16), connected to each other, adjoin the movable top sheet (12), enclosing the pipe (13) from above. 6. A plug according to claim 2, characterized in that two, three or four retaining grips (15, 16, 20, 21), adjacent, are connected to each other and to the top sheet (12). 7. The plug according to claim 1, characterized in that the holding grips (15, 16, 20, 21) are made with the possibility of fixing in the tap hole (4) or on the cold outer edge (24) of the tap hole (4). 8. Plug according to claim 1, characterized in that the retaining jaws (15, 16, 20, 21) are made of reinforcing steel 6 mm thick, bent at the lower free end (25), forming a hook (26), and with external dimensions + 30-50 mm, mainly 40 mm, more than the circumference of the cork and 3-10 cm more than the length of its body (8). 9. Plug according to claim 1, characterized in that its body (8), in order to reduce the total weight, contains, in addition to light bodies (10) made of low-melting hydrocarbon compounds, additional light bodies (28) in the form of mineral hollow balls consisting of foam glass ( 28 ', 28). 10. Plug according to claim 1, characterized in that viscous oils are mixed into its body (8) in order to optimize good deformability. 11. Plug according to claim 1, characterized in that its body (8) consists of a mixture: 10-50 vol.% Granulate (10 ') polystyrene 0.3-5 mm, 5-30 vol.% Additional hollow bodies (28 ') in the form of hollow balls of sodium silicate / calcium 0.2-8 - 4 038416 mm, 20-45 wt.% Of additional hollow bodies (28) in the form of aluminosilicate hollow balls with a diameter of 0.1-1.5 mm, 15-70 wt.% Clay mixture (9) of kaolinite, bentonite and clay 3-layer silicate, 0.5-3 wt.% Plasticizer, 0.1-2 wt% thinner, 0.1-2 wt% temporary binder, 0.1-5 wt.% Permanent binder and 2-8 vol.% Oils as a forming aid. 12. Plug according to claim 9, characterized in that polystyrene granulate (10 ') in the form of 2-3 mm, foam glass (28') in the form of 0.2-0.5 mm, aluminosilicate hollow balls (28) in the form of 0 , 1-0.5 mm in diameter form a plug body (8) with other components of the mixture. 13. Stopper according to claim 9, characterized in that the polystyrene granulate (10 ') has an irregular shape of the coffee beans. 14. Plug according to claim 9, characterized in that the polystyrene granulate (10 ') is graphitized polystyrene.