WO2023241241A1 - Converter sliding taphole and whole-process steel-tapping slag-blocking method - Google Patents

Abstract

The present invention relates to a converter sliding taphole and a whole-process steel-tapping slag-blocking method. In the present invention, the center of the cross-section of an air-permeable ceramic rod is arranged between a center line and an outer ring of the cross-section of a taphole brick, and the distance between the outer ring of the cross-section of the air-permeable ceramic rod and the outer ring of the cross-section of the taphole brick is defined to be 20-25 mm. After blowing-in argon gas, argon bubbles form an annular air curtain barrier directly in front of the periphery of the taphole, which, on the one hand, blocks steel slag which is about to enter the taphole along with the steel flow, and on the other hand, effectively reduces the height of a suction vortex above the taphole. The invention overcomes a key technical problem of the tapping process whereby steel slag is mixed into a steel flow exiting a taphole, and eliminates the defect of existing converter sliding taphole slide plates which are unable to block intermediate slag. By means of gas-blowing slag blocking and slide-plate slag blocking, the invention achieves slag-controlled tapping during the whole process of converter tapping, reducing the amount of slag outputted by the converter, reducing the erosion and scouring of the inner wall of a steel flow channel by slag, and extending service life.

Description

A converter sliding taphole and a method for retaining slag throughout the tapping process Technical field

The invention relates to a sliding taphole of a converter and a method for retaining slag during tapping, and belongs to the technical field of iron and steel metallurgy and steelmaking.

Background technique

In order to optimize the slag blocking technology for converter tapping, more than ten slag blocking methods have been invented at home and abroad, including pneumatic slag blocking method, electromagnetic slag blocking method, vacuum slag suction method, siphon tapping method, etc. However, the success rate of slag blocking is low and the effect is ineffective. Ideal, the converter sliding taphole slag control tapping technology developed in China in recent years has a high slag blocking success rate and good slag blocking effect, and has been widely used. However, there are still the following problems or deficiencies in production applications: (1) Converter sliding The tap hole uses a sliding plate to block slag, which can only block 30% of the early slag and 40% of the late slag, but cannot block 30% of the intermediate slag during the tapping process. The intermediate slag is mainly involved in the molten steel and enters the tapping process. Steel slag in the tap hole, and the current tapping slag blocking technology cannot effectively block the mid-term slag; (2) During the tapping process, swirling flow is generated at the tap hole, and the steel slag is involved in the molten steel and enters the sliding tap hole, which intensifies the The erosion and erosion of the inner walls of the steel flow holes in the taphole, inner nozzle, and outer nozzle reduce the service life and affect the converter operation rate; (3) Steel slag enters the sliding taphole along with the molten steel. When the sliding plate is closed to block the slag, the steel slag will Entering the slideway between skateboards will cause slag to be trapped between the upper and lower skateboard bricks, aggravating the damage to the sliding surface of the skateboard, seriously affecting the service life of the skateboard, and even causing an accident of steel penetration between the skateboards.

Chinese patent document CN207828342U (Patent No.: 201721701961.0) discloses a plum blossom taphole assembly brick, including: an inner nozzle brick, a seamless steel pipe for tapping the taphole assembly, an end brick of the taphole assembly, and a tappet assembly brick. Tap hole assembly transition brick, tap hole assembly round hole tap hole brick, tap hole assembly plum blossom tap hole brick, tap hole assembly plum blossom tap hole tail brick, retaining ring tube for grouting material, tap hole assembly The cover plate is used for assembling the outlet assembly, assembling the seamless steel pipe cross, and the inner water outlet pressure plate. The plum blossom taphole assembly brick provided by the utility model is suitable for the converter slide plate to retain the slag tapping device. It relies on the plum blossom-shaped flow steel hole to effectively prevent or It alleviates the phenomenon of eddy currents causing slag entrainment during the flow of molten steel, and improves the tapping speed and the quality of molten steel. The shortcomings of this patented technology: This patent uses plum blossom-shaped petals to change the rotation angle vector of the molten steel fluid in the converter tap hole. It functions to suppress the scale and quantity of eddy currents generated by the steel flow, and has no active slag-blocking effect. With the erosion of the tap hole, the plum blossom shape gradually loses its shape and fails, and cannot continue to be effective.

Chinese patent document CN106041044B (Patent No.: 201610634268. There are annular and evenly arranged ceramic tubes and an annular air chamber. The air chamber is located at the bottom of the ceramic tube and connected with the breathable ceramic tube. The upper part of the ceramic tube extends 5 to 10 mm from the upper surface of the water outlet seat brick body. The air chamber There is an air inlet pipe connected to the side of the chamber. One end of the air inlet pipe is connected to the air chamber, and the other end extends from the side of the water outlet seat brick body. It connects the metal pipe fittings to the external argon gas source. After the argon gas is blown in, upwards An annular air curtain barrier is formed to wash the liquid steel entering the upper nozzle to promote the floating and removal of inclusions. A certain number of argon bubbles will enter the upper nozzle along with the steel flow to form a stable and continuous annular air flow. It not only suppresses the nodule problem at the nozzle, but also solves the problem of subcutaneous bubbles in the cast slab caused by the entry of protective argon bubbles into the steel. Disadvantages of this patented technology: This patent is mainly used to solve the problem of nodulation at the tundish nozzle. In order to ensure that a certain number of argon bubbles enter the upper nozzle along with the steel flow to form a stable and continuous annular air flow, the position of the ceramic tube is It needs to be close to the water supply side, resulting in a small range of argon blowing. Moreover, the tundish is used for steel continuous casting. There are only tiny inclusions and small particles of steel slag in the molten steel. Therefore, the ceramic tube arrangement of the tundish is not suitable for converter tapping. The demand for slag blocking at the nozzle; in addition, the diameter of the flow steel hole in the upper nozzle seat brick of the continuous casting tundish is small, and the molten steel flow is small, which will not erode the ceramic tube arranged in the middle of the nozzle seat brick body. However, the taphole diameter of the converter is expanded. Large, large flow of molten steel will erode the ceramic tube arranged in the middle of the converter tap port body, causing the life of the ceramic tube and the converter tap port body to be out of sync, thereby affecting the life of the converter tap port.

Chinese patent document CN112593043A (202011499478.5) A device for reducing the amount of slag dropped during the tapping process of a steelmaking converter, including a converter, a converter tapping port, and a gas source structure; the converter has a furnace lining on the inner wall, and the furnace lining is made of a permanent layer of magnesia bricks. The furnace lining is covered with working layer bricks; the taphole is provided with a thick refractory pipe. The wall of the refractory pipe is provided with a plurality of evenly distributed long air inlet holes, and an annular air chamber is provided at the bottom. The bottom ends of the long air inlet holes are respectively connected with the annular air chambers. Although the above solution can effectively suppress the vortex slag entrainment during the steel tapping process and reduce the amount of slag dropped during the steelmaking converter tapping process, the above-mentioned patent mainly It is to reasonably adjust the flow rate of argon gas according to the size of the blown slag surface in the converter. By blowing in argon gas with a certain pressure, the slag covering the molten steel surface above the tapping port is blown away to form a slag-free zone to avoid tapping. The vortex entrains slag during the process. Therefore, in order to ensure the formation of an effective high-pressure gas flow, the diameter of the long air inlet hole of the above patent is 0.5~1.5mm. Although it can form a slag-free zone above the vortex, it is easy to penetrate into the long air inlet hole. Molten steel, resulting in low or even no ventilation, and the need to increase the blowing pressure will cause the air inlet long hole to be blocked in the front and top in the back, which can easily lead to cracks in the air inlet long hole, causing the refractory tube to crack or even break, resulting in the loss of the air blowing function. And affect the life of the tap hole.

Contents of the invention

In view of the shortcomings of the existing technology, the present invention provides a sliding taphole of a converter and a method for retaining slag during tapping. This invention provides breathable ceramics eccentrically outside the taphole brick body along the thickness direction of the taphole brick body. After the argon gas is blown into the steel rod, the argon bubbles form an annular air curtain barrier right in front of the taphole, which not only blocks the steel slag that is about to enter the taphole with the steel flow, but also effectively reduces the vortex caused by the steel flow inhalation above the taphole. circumferential speed, reducing the height of the suction vortex generated, overcoming the key technical problem of steel slag being mixed into the steel flow flowing out of the taphole, and eliminating the defect that the sliding slag plate of the existing converter's sliding taphole cannot block the mid-term slag. , realizes slag-controlled tapping of the converter throughout the tapping process, further reduces the amount of slag in the converter, reduces the corrosion and erosion of the steel slag on the inner walls of the taphole, inner water outlet, and outer water outlet, and improves the efficiency of the taphole, The service life of the inner and outer water inlets.

The technical problems to be solved by the present invention are achieved by adopting the following technical solutions: a converter sliding tap hole, which is arranged in the converter tap hole installation hole, with the side close to the converter as the inner end, and outside the converter tap hole installation hole. The end of the converter is provided with a sliding plate slag-stopping device. The sliding plate slag-stopping device includes an inner nozzle, a sliding plate and an outer nozzle arranged in sequence from one side of the converter taphole installation hole; the converter sliding taphole includes a taphole brick body. , air chamber box, breathable ceramic rod, air inlet pipe and flow steel hole;

The cylindrical flow steel hole is arranged at the center of the taphole brick body along the axial direction of the taphole brick body. The breathable ceramic rod, air chamber box and air inlet pipe are arranged along the axis of the taphole brick body from the inner end to the taphole brick body. The outer ends are arranged inside the taphole brick body in turn;

The cross-section of the air chamber box is annular, the air chamber box is coaxially arranged with the flow steel hole, and the breathable ceramic The rods are evenly arranged in an annular shape along the circumferential direction of the air chamber box. The outer end of the breathable ceramic rod is connected to the air chamber box. The inner end of the breathable ceramic rod extends out of the inner end of the outlet brick body; the air inlet pipe The inner end of the air chamber box is connected to the outer end surface of the air chamber box, and the outer end of the air inlet pipe extends from the outer end side of the taphole brick body. The air inlet pipe is used to connect the external argon gas source;

The cross-sectional center of the breathable ceramic rod is located between the center line of the cross-section of the taphole brick body and the outer ring of the cross-section of the taphole brick body. The outer ring of the cross-section of the breathable ceramic rod is outside the cross-section of the taphole brick body. The distance m of the circle is 20~25mm;

The breathable ceramic rod is provided with breathable holes along the axial direction of the breathable ceramic rod. The breathable holes extend longitudinally through the inner and outer end faces of the breathable ceramic rod. The breathable holes are evenly distributed on the cross section of the breathable ceramic rod.

Preferably, the number of breathable ceramic rods is 6 to 9, the number of breathable ceramic rods is 40 to 80, and the inner diameter of the breathable holes is 0.18 to 0.20 mm.

Preferably in the present invention, the breathable ceramic rod is cylindrical, the outer diameter of the cylinder is 20 to 30 mm, and the length L of the breathable ceramic rod is 200 to 400 mm.

Preferably in the present invention, the air chamber box is a metal box with a square longitudinal section, and the side length a of the square is 30 to 40 mm. The metal box is made of two annular plates with an L-shaped longitudinal section, and the two Ring plates are welded to each other;

The depth x of the breathable ceramic rod inserted into the air chamber box is 5 to 10 mm, and the length y of the breathable ceramic rod extending out of the inner end of the tapping brick body is 5 to 10 mm.

Preferably in the present invention, the outer end of the taphole brick body is provided with a female port, and the shape and size of the female port are consistent with the shape and size of the sub-port of the internal water port.

Preferably in the present invention, the taphole brick body is formed by isostatic pressing of magnesia carbon, with a volume density of ≥2.92g/cm ³ , a normal temperature compressive strength of ≥45.4Mpa, a normal temperature flexural strength of ≥22.9Mpa, and an MgO content of ≥75 %, C content is 18% ~ 19%.

Preferably, the air inlet pipe is a heat-resistant stainless steel round pipe with an outer diameter of 12 to 16 mm and a wall thickness of 1.2 to 2.3 mm.

Preferably in the present invention, the breathable ceramic rod is formed into the taphole brick body by isostatic pressing of zirconium corundum.

Technical concept of the present invention: In the present invention, evenly arranged through-ventilation holes are provided in the breathable ceramic rod along the axial direction of the breathable ceramic rod, which can generate a large number of tiny bubbles. The principle of slag blocking in the present invention is to pass the bricks along the taphole The breathable ceramic rods arranged axially on the body blow into the argon gas, which can form a large number of tiny bubbles, thus forming an annular air curtain barrier directly in front of the tap hole. On the one hand, it can block the steel slag that is about to enter the tap hole with the steel flow. On the other hand, it can effectively reduce the circumferential velocity of the steel flow suction vortex above the tapping port, thereby reducing the height of the suction vortex. Since the steel slag floats on the surface of the molten steel, the vortex starts to form from the liquid surface, and the steel slag is distributed around the vortex. , when the height of the vortex is reduced, the lower end of the vortex will move away from the tap hole, thus effectively inhibiting steel slag from entering the tap hole.

In addition, since the vortex is formed on the surface of the molten steel, and the cross-sectional area of the vortex becomes larger and larger from bottom to top, and the circumferential velocity of the liquid surface in the outer ring of the vortex is positively correlated with the formation of the vortex and the depth of the vortex, the present invention uses breathable ceramics The center of the cross-section of the rod is set between the center line of the cross-section of the taphole brick body and the outer ring of the cross-section of the taphole brick body, and defines the distance between the outer ring of the cross-section of the breathable ceramic rod and the outer ring of the cross-section of the taphole brick body. The distance is 20~25mm. While ensuring the overall strength of the taphole brick body is qualified, the bubbles generated by the breathable ceramic rod can effectively reduce the circumferential velocity of the liquid surface in the vortex outer ring, thereby achieving the optimal slag-blocking effect, and can It reduces the impact of the breathable ceramic rod by the steel flow and increases the service life of the steel tap.

The breathable ceramic rod of the present invention is arranged eccentrically outside the taphole brick body along the thickness direction of the taphole brick body. The distance m between the outer wall of the breathable ceramic rod and the outer wall of the taphole brick body is 20 to 25 mm. The number is 6 to 9, evenly arranged in a circular shape, the outer diameter of the breathable ceramic rods is 20 to 30mm, and the length L of the breathable ceramic rods is 200 to 400mm. The design is based on the invention that the sliding taphole of the converter adopts air blowing The tasks of slag blocking and sliding plate slag blocking, improving the slag blocking effect of the sliding taphole and the service life of the taphole are verified by technicians in this field through a large number of numerical physics simulation research experiments and industrial application tests.

The present invention unexpectedly discovered during simulation research experiments that breathable ceramic rods are installed in the taphole brick body. After air is blown, an annular air curtain barrier is formed directly in front of the taphole, which can not only block the upcoming steel flow. The steel slag entering the tap port can effectively reduce the circumferential velocity of the steel flow suction vortex above the tap port, reduce the height of the suction vortex, effectively inhibit the steel slag from entering the tap port, and overcome the problem of steel slag flowing out from the tap port. The key technical problem of steel slag mixed in the steel flow. In addition, it was found that the technical solution of eccentric arrangement of the breathable ceramic rods can increase the scope of argon blowing to prevent slag. The number and outer diameter of the breathable ceramic rods and the flow rate of the blown argon gas have a great influence on the blowing. The effect of slag blocking has a direct impact. Specifically, the number and outer diameter of breathable ceramic rods determine the amount of air permeability. The greater the number of breathable ceramic rods and the larger the outer diameter, the greater the air permeability. The flow rate of the incoming argon gas has a direct impact on the effect of air blowing and slag blocking. At the same time, it was unexpectedly found in the industrial application comparison test that the technical solution of eccentrically arranged outer ventilated ceramic rods not only increased the scope of argon blowing and slag blocking, reduced the amount of slag in the taphole, but also avoided the problem of taphole bricks. The problem of the expansion of the flow steel hole destroying the breathable ceramic rod has been achieved, and the service life of the breathable ceramic rod and the taphole brick body have been synchronized. In addition, in the development, production and application test of the converter sliding taphole brick of the present invention, it was found that the breathable ceramic rod The distance m between the outer wall of the taphole brick and the outer wall of the taphole brick body is less than 20mm. The taphole brick body is prone to surface cracks, which affects the quality and thus affects the service life of the taphole brick. After a large number of research experiments and application tests, the present invention The optimal distance m between the outer wall of the breathable ceramic rod and the outer wall of the taphole brick body, the outer diameter of the breathable ceramic rod ￠, and the control parameters for blowing argon gas into the breathable ceramic rod were determined.

In addition, the present invention also determines the length L of the breathable ceramic rod to be 200 to 400 mm based on the erosion length of the tap hole. If the length L is too large, it will affect the development quality and preparation cost of the breathable ceramic rod. If the length L is too small, it will affect the quality of the breathable ceramic rod. Argon blowing effect and service life, etc.

The converter sliding taphole brick tapping designed according to the present invention has achieved unexpected results: the invention realizes slag-controlled tapping in the whole process of converter tapping by blowing air to block slag and sliding plate to block slag, further reducing the number of steps under the converter. The amount of slag is reduced, and the "swirl flow" phenomenon in the taphole is effectively suppressed, which reduces the corrosion and erosion of steel slag on the inner walls of the steel holes in the taphole, inner nozzle, and outer nozzle, and improves the efficiency of the sliding taphole brick, inner nozzle, and sliding plate. service life.

The invention also provides an installation method for the above-mentioned sliding taphole of the converter. The outer end of the installation hole of the converter taphole is provided with a flange, and the flange is connected with a flange for installing the sliding plate slag retaining device. a mounting plate, a base plate is arranged between the mounting plate and the flange, and the mounting plate is provided with a Positioning slot for the nozzle;

The installation method uses a special positioning device, which includes a seamless steel pipe, a positioning plate and a positioning inclined iron;

The seamless steel pipe is set in the flowing steel hole of the taphole brick body. A positioning plate is welded inside the seamless steel pipe. The positioning plate is provided with a bolt hole. The positioning plate is located at the outer end of the seamless steel pipe. On the side, the positioning inclined iron is detachably arranged on the positioning plate, and the positioning inclined iron is used to connect with the installation plate;

The positioning inclined iron is provided with a sub-port, and has the same shape and size as the sub-port of the internal water inlet;

The specific installation steps are as follows:

1) Use positioning bolts, flat washers, and fastening nuts to combine and fix the positioning plate on the taphole brick body with the positioning inclined iron, and then load the taphole brick body into the taphole outer seat brick with a forklift. In the tapping hole installation hole of the inner seat brick assembly of the tap hole, make the positioning inclined iron correctly fall into the positioning groove of the inner nozzle installation, and use a pneumatic tool to fix the positioning inclined iron and the installation plate with the movable joint bolt;

2) An air inlet pipe is provided between the flange and the base plate, and the air inlet pipe is connected to the air inlet pipe. The air inlet pipe is a heat-resistant stainless steel round pipe with an outer diameter of 12 to 16 mm and a wall thickness of 1.2 ~2.3mm; the main function of setting up seamless steel pipes and positioning plates is to achieve precise positioning when installing the outlet brick body to ensure accurate connection between the air inlet pipe and the air inlet pipeline; the seamless steel pipes and positioning plates will melt when encountering high-temperature molten steel If it falls, it will not affect the flow of molten steel in the tap hole;

3) Shake the converter to the position where the flow hole is vertically upward, use magnesium-calcium gunning material to spray the gap between the taphole brick body, the outer seat brick of the taphole, and the inner seat brick of the taphole, and then bake and sinter it. For 25 to 35 minutes, there is a waterproof sticker on the inner end of the breathable ceramic rod. The waterproof sticker is used to protect the breathable surface and prevent problems such as poor air permeability caused by water seepage and material seepage;

4) Swing the taphole of the converter to the front of the furnace, remove the positioning inclined iron, and install the inner nozzle of the sliding plate slag retaining device into the positioning groove;

5) After installing the sliding plate and outer nozzle on the sliding taphole mechanism, transport the sliding taphole mechanism with a forklift and install it on the installation plate. Use articulate bolts and surface pressure bolts to connect the sliding taphole mechanism to the installation plate. Fix them together, and finally perform the opening and closing debugging of the sliding taphole to complete the installation of the sliding taphole of the converter. The sliding tapping mechanism is used to control the opening and closing of the slide plate.

The magnesia-calcium gunning material is a conventional refractory material and is a commercially available product. The inner nozzle, sliding plate and outer nozzle are produced using existing technologies.

The positioning bolt model and specification is M30X80, the flat washer model and specification is ￠16, and the fastening nut model and specification is M30, all of which are commercially available products.

The invention also provides a method for retaining slag during tapping, using the above-mentioned converter sliding tapping port, and the air inlet of the air inlet pipe is connected with argon supply equipment, which includes the following steps:

When the converter starts shaking and preparing to tap steel, argon gas is turned on, and the argon gas flow rate is controlled at 20~30NL/min;

When all the steel has been tapped from the converter, close the sliding plate, rock the converter back to the normal smelting station and turn off the argon gas at the same time.

Beneficial effects of the present invention:

1) The sliding taphole of the converter of the present invention is provided with breathable ceramic rods in the taphole brick body, and the breathable ceramic rods are provided with evenly arranged through micro ventilation holes along the axial direction. After argon gas is blown in, a large number of microscopic ventilation holes can be formed. The argon bubbles form an annular air curtain barrier right in front of the tap hole, which not only inhibits the steel slag that is about to enter the tap hole with the steel flow, but also effectively reduces the circumferential velocity above the tap hole that causes the steel flow to be sucked into the vortex. , reducing the height of the suction vortex generated, effectively inhibiting steel slag from immersing in the tap hole, overcoming the key technical problem of steel slag being mixed into the steel flow flowing out of the tap hole during the tapping process, and eliminating the existing sliding tap hole of the converter The defect of the sliding plate slag blocking cannot block the mid-stage slag. The present invention realizes the slag controlled tapping in the whole process of converter tapping by blowing air slag blocking and sliding plate slag blocking, further reduces the amount of slag discharged from the converter, and reduces the impact of steel slag on the tapping port, The erosion and scouring of the inner wall of the steel holes at the inner and outer nozzles improves the service life. By applying the present invention, compared with the existing converter sliding taphole sliding plate slag-blocking and tapping technology, the amount of slag per ton of steel in the converter is reduced by more than 0.5kg year-on-year, and the lifespan of the converter taphole, internal nozzle, and sliding plate is increased by 50 heats and 30 heats respectively year-on-year. times, 3 times or more.

2) The present invention sets the center line of the cross-section of the breathable ceramic rod between the center line of the cross-section of the taphole brick body and the outer ring of the cross-section of the taphole brick body, and limits the outer ring of the cross-section of the breathable ceramic rod and the tappet The distance between the outer rings of the cross-section of the taphole brick body is 20 to 25mm. This ensures that the overall strength of the taphole brick body is qualified and at the same time achieves the optimal slag-blocking effect. It not only increases the scope of argon blowing and slag-blocking, but also reduces the cost. Tapping steel It can also reduce the impact of the steel flow on the breathable ceramic rod, and avoid the problem of damaging the breathable ceramic rod due to the expansion of the flow steel hole of the taphole brick, and realize the integration of the breathable ceramic rod and the taphole brick body. The service life is synchronized. Through comparison with the application test of the technical solution in which the breathable ceramic rods are arranged in the thickness center of the taphole brick body, the amount of slag per ton of steel in the converter is reduced by more than 0.1kg year-on-year, and the life of the converter taphole is increased by more than 20 heats year-on-year.

3) In the present invention, the breathable ceramic rod, the air chamber box and the air inlet pipe are arranged inside the taphole brick body in sequence from the inner end to the outer end along the axis of the taphole brick body, wherein the breathable ceramic rods are evenly arranged along the axial direction. The arranged ventilation holes can form a large number of tiny bubbles and effectively prevent the infiltration of molten steel. The air chamber box is set between the breathable ceramic rod and the air inlet pipe as a transit piece for gas exchange to evenly distribute the argon gas flow, and It can shorten the length of the breathable ceramic rod, reduce the difficulty and cost of preparing the converter tap hole, and is more conducive to popularization and application.

4) The installation method of the sliding taphole of the converter of the present invention is to design and install a special positioning device for the sliding taphole brick, realize the precise positioning and installation of the sliding taphole brick and the precise docking of the air inlet pipe and the air inlet pipeline, and solve this problem. Inventing another key technical problem in industrial application.

5) The air chamber box of the present invention is made of two annular plates with an L-shaped longitudinal section, and a slot is provided on the annular plate. The breathable ceramic rod can be directly inserted into the slot, which simplifies the air chamber box. The preparation process shortens the preparation time and improves the preparation quality.

6) The inner end of the breathable ceramic rod of the present invention extends out of the inner end surface of the taphole brick body. The position of the breathable ceramic rod can be fixed from the outside of the taphole brick body, and the outer end of the breathable ceramic rod is fixedly arranged in the air chamber. In the slot on the box, the breathable ceramic rod is isostatically pressed into the taphole brick body, which solves the problem of difficult positioning of the breathable ceramic rod.

Description of the drawings

Figure 1 is a schematic cross-sectional view of the structure of the sliding taphole of the converter in the embodiment of the present invention;

Figure 2 is an A-A cross-sectional view of the sliding taphole structure of the converter in the embodiment of the present invention;

Figure 3 is a schematic structural diagram of the air chamber box in the embodiment of the present invention;

Figure 4 is a schematic diagram of the assembly of the sliding taphole and the positioning inclined iron of the converter in the embodiment of the present invention;

Figure 5 is a schematic diagram of the installation of the sliding taphole of the converter in the embodiment of the present invention;

In the picture, 1 taplet brick body; 2 air chamber box; 3 breathable ceramic rod; 4 air inlet pipe; 5 seamless steel pipe; 6 bolt holes; 7 positioning plate; 8 waterproof sticker; 9 slot; 10 joint bolt; 11 Positioning inclined iron; 12 Positioning bolt; 13 Flat washer; 14 Fastening nut; 15 Flange plate; 16 Base plate; 17 Installation plate; 18 Sliding tap hole mechanism; 19 Internal water outlet; 20 Slide plate; 21 External water outlet; 22 air inlet pipe; 23 outer seat brick of the steel tap; 24 inner seat brick of the steel tap; 25 magnesium calcium gunning material.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and examples, but is not limited thereto.

In the embodiment, the magnesia-calcium gunning material 25, the seamless steel pipe 5, the positioning bolts 12, the flat gaskets 13, the fastening nuts 14, and the air inlet pipeline 22 are all conventional materials and are commercially available products.

Example 1

A converter sliding taphole, as shown in Figure 5, with the side close to the converter as the inner end. The outer end of the converter taphole installation hole is provided with a sliding plate slag-stopping device. The sliding plate slag-stopping device includes a sliding plate slag-stopping device formed by the converter outlet. An inner water outlet 19, a sliding plate 20 and an outer water outlet 21 are arranged outward in sequence on one side of the steel port mounting hole. As shown in Figures 1, 2 and 3, the sliding taphole of the converter includes a taphole brick body 1, an air chamber box 2, a breathable ceramic rod 3, an air inlet pipe 4 and a flow steel hole.

The taphole brick body 1 is formed by isostatic pressing of magnesia carbon, with a volume density ≥ 2.92g/cm ³ , a compressive strength at normal temperature ≥ 45.4Mpa, a flexural strength at normal temperature ≥ 22.9Mpa, an MgO content ≥ 75%, and a C content It is 18%~19%. The outer end of the taphole brick body 1 is provided with a female opening, and the shape and size of the female opening are consistent with the shape and size of the female opening of the internal nozzle 19 .

The taphole brick body 1 is cylindrical, and the cylindrical flowing steel hole is arranged at the center of the taphole brick body 1 along the axial direction of the taphole brick body 1. The breathable ceramic rod 3, the air chamber box 2 and the inlet The air pipes 4 are arranged inside the taphole brick body 1 in sequence from the inner end to the outer end along the axis direction of the taphole brick body 1 .

The cross-section of the air chamber box 2 is annular. The air chamber box 2 is coaxially arranged with the flow steel hole. The number of the breathable ceramic rods 3 is 6. The breathable ceramic rods 3 are arranged along the circumferential direction of the air chamber box 2. Evenly arranged in a circular shape, the outer end of the breathable ceramic rods 3 is connected to the air chamber box 2, and the inner end of the breathable ceramic rods 3 extends out of the tapping brick The inner end surface of the body 1 is provided; specifically, the upper part of the air chamber box 2 is provided with a slot 9, and the breathable ceramic rod 3 is inserted into the slot 9. The shape, size, and quantity of the slot 9 are consistent with the ceramics inserted into the slot 9. The shape, size and quantity of rod 3 are suitable. The air chamber box 2 is a metal box with a square longitudinal section. The side length a of the square is 40mm. The metal box is made up of two annular plates with an L-shaped longitudinal section. One of the annular plates is provided with There are slot 9.

The depth x of the breathable ceramic rod 3 inserted into the air chamber box 2 is 5 mm, the length y of the inner end of the breathable ceramic rod 3 extending out of the tapping brick body 1 is 10 mm, and the inner end of the breathable ceramic rod 3 A waterproof sticker 8 is provided on the end surface.

The cross-sectional center of the breathable ceramic rod 3 is located between the cross-sectional center line of the taphole brick body 1 and the outer ring of the cross-section of the taphole brick body 1. The outer ring of the cross-section of the breathable ceramic rod 3 is in contact with the taphole brick. The distance m between the outer ring of the cross section of body 1 is 20mm.

The breathable ceramic rod 3 is made of zirconium corundum isostatically pressed into the taphole brick body 1. The breathable ceramic rod 3 is cylindrical with an outer diameter of 30 mm. The length L of the breathable ceramic rod 3 is 400mm.

The breathable ceramic rod 3 is provided with a breathable hole along the axial direction of the breathable ceramic rod 3. The breathable hole longitudinally penetrates the inner end face and the outer end face of the breathable ceramic rod 3. The breathable ceramic rod 3 has a cross section. Evenly distributed.

The diameter of the ventilation holes is 0.18mm, and the ventilation holes are evenly distributed in the shape of 3 concentric rings, from the inside to the outside along the radial direction of the ventilation ceramic rod 3. The number of ventilation holes in the first ring is 9, and the number of ventilation holes in the second ring is 9. The number is 18, and the number of ventilation holes in the third ring is 27.

The inner end of the air inlet pipe 4 is connected to the outer end surface of the air chamber box 2, and the outer end of the air inlet pipe 4 protrudes from the outer end side of the taphole brick body 1. The air inlet pipe 4 is used to connect external argon gas. Air source, the air inlet pipe 4 is made of heat-resistant stainless steel round pipe, with an outer diameter of 16mm and a wall thickness of 2.3mm.

As shown in Figures 4 and 5, in the installation method of the converter sliding taphole of the present invention, a flange 15 is provided at the outer end of the converter taphole installation hole, and the flange 15 is connected with a flange for installing the The mounting plate 17 of the slide plate slag retaining device has a base plate 16 between the mounting plate 17 and the flange 15. The plate 17 is provided with a positioning groove for installing the internal water inlet 19 .

The installation method uses a special positioning device, which includes a seamless steel pipe 5, a positioning plate 7 and a positioning inclined iron 11.

The seamless steel pipe 5 is set in the flowing steel hole of the taphole brick body 1. A positioning plate 7 is welded inside the seamless steel pipe 5. The positioning plate 7 is provided with a bolt hole 6. The positioning plate 7 Located on the outer end side of the seamless steel pipe 5 , the positioning inclined iron 11 is detachably arranged on the positioning plate 7 , and the positioning inclined iron 11 is used to connect with the installation plate 17 .

The positioning inclined iron 11 is provided with a sub-port, and has the same shape and size as the sub-port of the internal water port 19 .

The specific installation steps are as follows:

1) Use positioning bolts 12, flat washers 13, and fastening nuts 14 to assemble and fix the positioning plate 7 on the taphole brick body 1 with the positioning inclined iron 11, and then install the taphole brick body 1 with a forklift. into the taphole installation hole of the combination of the taphole outer seat brick 23 and the taphole inner seat brick 24, so that the positioning inclined iron 11 correctly falls into the positioning groove for installing the inner nozzle 19, and a pneumatic tool is used to move the movable bolt 10 The positioning inclined iron 11 is fixed to the mounting plate 17.

2) An air inlet pipe 22 is provided between the flange 15 and the base plate 16 to connect the air inlet pipe 22 with the air inlet pipe 4 .

The air inlet pipe 4 is connected to the external argon gas source through the air inlet pipe 22 .

The air inlet pipe 22 is made of a heat-resistant stainless steel round pipe with an outer diameter of 16 mm and a wall thickness of 2.3 mm.

3) Shake the converter to the position where the flow hole is vertically upward, and use magnesia-calcium gunning material 25 to spray the gap between the taphole brick body 1, the taphole outer seat brick 23, and the taphole inner seat brick 24. Bake and sinter for another 35 minutes.

4) Rock the taphole of the converter to the front of the furnace, remove the positioning inclined iron 11, and install the inner water port 19 of the sliding plate slag retaining device into the positioning groove.

5) After installing the sliding plate 20 and the outer nozzle 21 on the sliding tap hole mechanism 18, transport the sliding tap hole mechanism 18 with a forklift and install it on the installation plate 17. Use articulate bolts and surface pressure bolts to secure the sliding tap hole. The opening mechanism 18 and the mounting plate 17 are fixed together, and finally the opening and closing debugging of the sliding taphole is completed. The installation of the converter sliding taphole, the sliding taphole mechanism 18 is used to control the opening and closing of the slide plate 20.

The present invention utilizes the sliding taphole of the converter to carry out the method of tapping and blocking slag throughout the whole process. The air inlet of the air inlet pipe 4 is connected to an argon supply equipment, which includes the following steps:

When the converter starts to rock and prepare to tap steel, argon gas is turned on and the argon gas flow rate is controlled at 30NL/min.

When all the steel has been tapped from the converter, close the sliding plate 20, rock the converter back to the normal smelting station and at the same time turn off the argon gas.

Example 2

The difference from the converter sliding taphole described in Example 1 is:

The distance m between the outer wall of the breathable ceramic rod 3 and the outer wall of the taphole brick body 1 is 25 mm.

The outer diameter of the breathable ceramic rod 3 is 20mm, and the length L of the breathable ceramic rod 3 is 200mm.

The side length a of the square cross-section of the air chamber box 2 is 30 mm, the depth x of the breathable ceramic rod 3 inserted into the air chamber box 2 is 10 mm, and the length y of the inner end of the tapping brick body 1 is 5 mm.

The diameter of the ventilation holes provided in the breathable ceramic rod 3 is 0.2mm. The ventilation holes are evenly distributed in the shape of three concentric rings, from the inside to the outside along the radial direction of the breathable ceramic rod 3. The number of ventilation holes in the first ring is 6. The number of ventilation holes in the second ring is 12, and the number of ventilation holes in the third ring is 18.

The number of breathable ceramic rods 3 is 9.

The outer diameters of the air intake pipe 4 and the air intake pipeline 22 are both 12 mm, and the wall thickness is 1.2 mm.

The present invention utilizes the sliding taphole of the converter to carry out a method for retaining slag during the entire tapping process, which includes the following steps:

When the converter starts shaking and preparing to tap steel, the argon gas is turned on, and the argon gas flow is controlled at 20NL/min. When the converter completes tapping and shakes back to the normal smelting station, the argon gas is turned off.

Example 3

The difference from the converter sliding taphole described in Example 1 is:

The distance m between the outer wall of the breathable ceramic rod 3 and the outer wall of the taphole brick body 1 is 22 mm.

The outer diameter of the breathable ceramic rod 3 is 22mm, and the length L of the breathable ceramic rod 3 is 300mm.

The side length a of the square cross-section of the air chamber box 2 is 35 mm, the depth x of the breathable ceramic rod 3 inserted into the air chamber box 2 is 7 mm, and the length y of the inner end of the tapping brick body 1 is 7 mm.

The diameter of the ventilation holes provided in the breathable ceramic rod 3 is 0.19mm. The ventilation holes are evenly distributed in the shape of three concentric rings, from the inside to the outside along the radial direction of the breathable ceramic rod 3. The number of ventilation holes in the first ring is 8. The number of ventilation holes in the second ring is 16, and the number of ventilation holes in the third ring is 24.

The number of breathable ceramic rods 3 is 9.

The outer diameters of the air intake pipe 4 and the air intake pipeline 22 are both 14mm, and the wall thickness is 2.3mm.

In the installation method of the converter sliding taphole of the present invention, the outer end of the converter taphole installation hole is provided with a flange 15, and the flange 15 is connected to a mounting plate 17 for installing the sliding plate slag retaining device. A base plate 16 is provided between the mounting plate 17 and the flange 15 . The mounting plate 17 is provided with a positioning groove for installing the internal water inlet 19 .

The installation method uses a special positioning device, which includes a seamless steel pipe 5, a positioning plate 7 and a positioning inclined iron 11.

The seamless steel pipe 5 is set in the flowing steel hole of the taphole brick body 1. A positioning plate 7 is welded inside the seamless steel pipe 5. The positioning plate 7 is provided with a bolt hole 6. The positioning plate 7 Located on the outer end side of the seamless steel pipe 5 , the positioning inclined iron 11 is detachably arranged on the positioning plate 7 , and the positioning inclined iron 11 is used to connect with the installation plate 17 .

The positioning inclined iron 11 is provided with a sub-port, and has the same shape and size as the sub-port of the internal water port 19 .

The specific installation steps are as follows:

1) Use positioning bolts 12, flat washers 13, and fastening nuts 14 to assemble and fix the positioning plate 7 on the taphole brick body 1 with the positioning inclined iron 11, and then install the taphole brick body 1 with a forklift. into the taphole installation hole of the taphole outer seat brick 23 and the taphole inner seat brick 24, so that the positioning inclined iron 11 can correctly fall into the positioning groove of the inner water port 19, and use a pneumatic tool to move the movable bolt 10 The positioning inclined iron 11 is fixed to the mounting plate 17.

2) An air inlet pipe 22 is provided between the flange 15 and the base plate 16 to connect the air inlet pipe 22 with the air inlet pipe 4 .

3) Shake the converter to the position where the flow hole is vertically upward, and use magnesia-calcium gunning material 25 to spray the gap between the taphole brick body 1, the taphole outer seat brick 23, and the taphole inner seat brick 24. Bake and sinter for another 30 minutes bell.

4) Rock the taphole of the converter to the front of the furnace, remove the positioning inclined iron 11, and install the inner water port 19 of the sliding plate slag retaining device into the positioning groove.

5) After installing the sliding plate 20 and the outer nozzle 21 on the sliding tap hole mechanism 18, transport the sliding tap hole mechanism 18 with a forklift and install it on the installation plate 17. Use articulate bolts and surface pressure bolts to secure the sliding tap hole. The mouth mechanism 18 is fixed with the installation plate 17. Finally, the opening and closing of the sliding tap hole is debugged to complete the installation of the sliding tap hole of the converter. The sliding tap hole mechanism 18 is used to control the opening and closing of the slide plate 20.

The present invention utilizes the sliding taphole of the converter to carry out a method for retaining slag during the entire tapping process, which includes the following steps:

When the converter starts shaking and preparing to tap steel, turn on the argon gas and control the argon gas flow rate at 25NL/min. When the converter starts shaking and prepare for tapping steel, turn on the argon gas and control the argon gas flow rate at 30NL/min. Wait until the converter When the steel is tapped out, the slide plate 20 is closed, and the argon gas is turned off while swinging back to the normal smelting station.

Comparative example 1

Chinese patent document CN207828342U (Patent No.: 201721701961.0) discloses a plum blossom taphole assembly brick. The sub-port width of the internal water inlet is 45mm. The upper slide plate is inlaid with a zirconium ring, the lower slide plate is inlaid with a zirconium plate, and a sliding tappet slide block is used. Slag tapping.

Comparative example 2

In Embodiment 1 of the present invention, the center of the cross-section of the breathable ceramic rod 3 is located between the center line of the cross-section of the taphole brick body 1 and the outer ring of the cross-section of the taphole brick body 1, and is changed to the cross-section of the breathable ceramic rod 3 The center is set to coincide with the cross-sectional center line of the taphole brick body 1, and everything else is the same.

Examples 1 to 3 and Comparative Examples 1 and 2 were used to conduct application tests and comparative tests on the sliding taphole of a 120t converter in the steelmaking plant of Yinshan Steel Co., Ltd. of Laiwu Iron and Steel Group. The results are as shown in Table 1. The converter of the present invention The taphole blowing effect is obvious. The average slag content per ton of steel in the converter using the taphole of the present invention is less than 2.35kg, which is a year-on-year decrease of more than 0.5kg compared to Comparative Example 1. The service life of the converter taphole, internal nozzle, and sliding plate is consistent with the comparison. Compared with proportion 1, the production has increased by more than 50 heats, 30 heats, and 3 heats respectively year-on-year, and at the same time, the steel penetration accident caused by slag inclusion on the slide has been avoided.

In the present invention, the center of the cross section of the breathable ceramic rod 3 is set between the center line of the cross section of the taphole brick body 1 and the outer ring of the cross section of the taphole brick body 1. The outer eccentric process layout is more reasonable, and the air blowing and slag blocking effect is more reasonable. It is better than Comparative Example 2. Compared with Comparative Example 2, the average slag amount per ton of steel in the converter is reduced by more than 0.1kg year-on-year. The service life of the converter taphole, internal nozzle, and sliding plate is increased by 20 heats, 5 heats, and 1 heat year-on-year. above. The comparison results are shown in Table 1.

Table 1

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the embodiments, those of ordinary skill in the art will understand that modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and they shall all be covered by the scope of the present invention. within the scope of the claims.

Claims (10)

A converter sliding tap hole is arranged in a converter tap hole installation hole, with the side close to the converter as the inner end. The outer end of the converter tap hole installation hole is provided with a sliding plate slag blocking device, and the sliding plate slag blocking device It includes an inner nozzle (19), a sliding plate (20) and an outer nozzle (21) arranged in sequence from one side of the converter taphole installation hole; it is characterized in that: the converter sliding taphole includes a taphole brick body ( 1), air chamber box (2), breathable ceramic rod (3), air inlet pipe (4) and flow steel hole; The cylindrical flow steel hole is arranged at the center of the taphole brick body (1) along the axial direction of the taphole brick body (1). The breathable ceramic rod (3), air chamber box (2) and air inlet pipe (4) They are arranged inside the taphole brick body (1) in sequence from the inner end to the outer end along the axis direction of the taphole brick body (1); The cross-section of the air chamber box (2) is annular, the air chamber box (2) is coaxially arranged with the flow steel hole, and the breathable ceramic rod (3) is circular along the circumferential direction of the air chamber box (2). Evenly arranged, the outer end of the breathable ceramic rod (3) is connected to the air chamber box (2), and the inner end of the breathable ceramic rod (3) extends out of the inner end surface of the tapping brick body (1); the inlet The inner end of the air pipe (4) is connected to the outer end surface of the air chamber box (2), and the outer end of the air inlet pipe (4) protrudes from the outer end side of the taphole brick body (1). The air inlet pipe (4) ) is used to connect to an external argon gas source; The center of the cross section of the breathable ceramic rod (3) is located between the center line of the cross section of the taphole brick body (1) and the outer ring of the cross section of the taphole brick body (1). The cross section of the breathable ceramic rod (3) The distance m between the outer ring and the outer ring of the cross-section of the taphole brick body (1) is 20~25mm; The breathable ceramic rod (3) is provided with a breathable hole along the axial direction of the breathable ceramic rod (3), and the breathable hole longitudinally penetrates the inner end face and the outer end face of the breathable ceramic rod (3). The ceramic rods (3) are evenly distributed across the cross section. The converter sliding taphole according to claim 1, characterized in that: the number of the breathable ceramic rods (3) is 6 to 9, the number of the breathable holes is 40 to 80, and the inner diameter of the breathable holes is 0.18～0.20mm. The converter sliding taphole according to claim 1 or 2, characterized in that: the breathable ceramic rod (3) is cylindrical, the outer diameter of the cylinder is 20~30mm, and the length of the breathable ceramic rod (3) L It is 200~400mm. The converter sliding taphole according to claim 1 or 2, characterized in that: the air chamber box (2) is a metal box with a square longitudinal section, and the side length a of the square is 30 to 40 mm. The metal box It is composed of two annular plates with an L-shaped longitudinal section; The depth x of the breathable ceramic rod (3) inserted into the air chamber box (2) is 5 to 10 mm, and the length y of the inner end of the breathable ceramic rod (3) extending out of the taphole brick body (1) is 5 ~10mm. The converter sliding taphole according to claim 1 or 2, characterized in that: the outer end of the taphole brick body (1) is provided with a female port, and the shape and size of the female port are consistent with the internal water port ( 19) The shape and size of the mouth are consistent. The converter sliding taphole according to claim 1 or 2, characterized in that: the taphole brick body (1) is formed by isostatic pressing of magnesia carbon, with a volume density of ≥2.92g/cm ³ and normal temperature pressure resistance. Strength ≥45.4Mpa, room temperature flexural strength ≥22.9Mpa, MgO content ≥75%, C content 18% to 19%. The converter sliding taphole according to claim 1 or 2, characterized in that the air inlet pipe (4) is a heat-resistant stainless steel round pipe with an outer diameter of 12 to 16 mm and a wall thickness of 1.2 to 2.3 mm. The sliding taphole of a converter according to claim 1 or 2, characterized in that the breathable ceramic rod (3) is isostatically pressed into the taphole brick body (1) using zirconium corundum. A method for installing a converter sliding tap hole according to any one of claims 1 to 8, characterized in that: a flange plate (15) is provided at the outer end of the converter tap hole installation hole, and the flange plate (15 ) is connected to a mounting plate (17) for installing the sliding plate slag retaining device. A base plate (16) is arranged between the mounting plate (17) and the flange (15). The mounting plate (17) is provided with There is a positioning groove for installing the internal water inlet (19); The installation method adopts a special positioning device, which includes a seamless steel pipe (5), a positioning plate (7) and a positioning inclined iron (11); The seamless steel pipe (5) is set in the flowing steel hole of the taphole brick body (1). A positioning plate (7) is welded inside the seamless steel pipe (5). The positioning plate (7) is provided with There are bolt holes (6), the positioning plate (7) is located on the outer end side of the seamless steel pipe (5), and the positioning inclined iron (11) is detachably set On the positioning plate (7), the positioning inclined iron (11) is used to connect with the mounting plate (17); The positioning inclined iron (11) is provided with a sub-port, and has the same shape and size as the sub-port of the internal water port (19); The specific installation steps are as follows: 1) Use positioning bolts (12), flat washers (13), and fastening nuts (14) to combine and fix the positioning plate (7) on the taphole brick body (1) with the positioning inclined iron (11). , use a forklift to install the taphole brick body (1) into the taphole installation hole combined with the taphole outer seat brick (23) and the taphole inner seat brick (24), so that the positioning inclined iron (11) can be correctly placed. into the positioning groove where the internal water inlet (19) is installed, and use a pneumatic tool to fix the positioning inclined iron (11) and the installation plate (17) with the hinge bolt (10); 2) An air inlet pipe (22) is provided between the flange (15) and the base plate (16). The air inlet pipe (22) is a heat-resistant stainless steel round pipe with an outer diameter of 12 to 16 mm and a wall thickness of is 1.2~2.3mm, connect the air inlet pipe (22) and the air inlet pipe (4); 3) Shake the converter to the position where the flow steel hole (100) is vertically upward, and use magnesia-calcium gunning material (25) to spray the taphole brick body (1), the taphole outer seat brick (23), and the taphole. The gap between the seat bricks (24) in the mouth is then baked and sintered for 25 to 35 minutes; 4) Swing the taphole of the converter to the front of the furnace, remove the positioning inclined iron (11), and install the inner nozzle (19) of the sliding plate slag retaining device into the positioning groove; 5) After installing the sliding plate (20) and the outer nozzle (21) on the sliding tap hole mechanism (18), transport the sliding tap hole mechanism (18) with a forklift and install it on the installation plate (17). The joint bolts and surface pressure bolts fix the sliding taphole mechanism (18) and the installation plate (17) together. Finally, the opening and closing debugging of the sliding taphole is carried out to complete the installation of the sliding taphole of the converter. The steel mouth mechanism (18) is used to control the opening and closing of the slide plate (20). A method for retaining slag during the entire tapping process, which adopts the converter sliding tap hole described in any one of claims 1 to 8, and is characterized in that it includes the following steps: When the converter starts shaking and preparing to tap steel, argon gas is turned on, and the argon gas flow rate is controlled at 20~30NL/min; After all the steel has been tapped from the converter, close the sliding plate (20), swing the converter back to the normal smelting position and close it at the same time. Argon.