CN115041672A - Tundish turbulence controller, installation method and argon blowing method for steel for pipeline - Google Patents
Tundish turbulence controller, installation method and argon blowing method for steel for pipeline Download PDFInfo
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- CN115041672A CN115041672A CN202210686926.5A CN202210686926A CN115041672A CN 115041672 A CN115041672 A CN 115041672A CN 202210686926 A CN202210686926 A CN 202210686926A CN 115041672 A CN115041672 A CN 115041672A
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- turbulence controller
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- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 title claims abstract description 96
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 55
- 239000010959 steel Substances 0.000 title claims abstract description 54
- 229910052786 argon Inorganic materials 0.000 title claims abstract description 48
- 238000000034 method Methods 0.000 title claims abstract description 32
- 238000007664 blowing Methods 0.000 title claims abstract description 22
- 238000009434 installation Methods 0.000 title abstract description 14
- 238000009749 continuous casting Methods 0.000 claims abstract description 53
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 30
- 229910052749 magnesium Inorganic materials 0.000 claims description 30
- 239000011777 magnesium Substances 0.000 claims description 30
- 238000005266 casting Methods 0.000 claims description 14
- 239000004744 fabric Substances 0.000 claims description 11
- 239000007788 liquid Substances 0.000 claims description 10
- 230000008569 process Effects 0.000 claims description 10
- 239000011248 coating agent Substances 0.000 claims description 9
- 238000000576 coating method Methods 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 claims description 9
- 229910052596 spinel Inorganic materials 0.000 claims description 9
- 239000011029 spinel Substances 0.000 claims description 9
- 238000011049 filling Methods 0.000 claims description 7
- 238000010276 construction Methods 0.000 claims description 6
- 239000007789 gas Substances 0.000 claims description 6
- 239000010935 stainless steel Substances 0.000 claims description 4
- 229910001220 stainless steel Inorganic materials 0.000 claims description 4
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 3
- RWDBMHZWXLUGIB-UHFFFAOYSA-N [C].[Mg] Chemical compound [C].[Mg] RWDBMHZWXLUGIB-UHFFFAOYSA-N 0.000 claims description 3
- 238000000462 isostatic pressing Methods 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 3
- 239000002699 waste material Substances 0.000 claims description 3
- 230000006835 compression Effects 0.000 claims 1
- 238000007906 compression Methods 0.000 claims 1
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- 238000002474 experimental method Methods 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 4
- 238000007667 floating Methods 0.000 description 4
- 238000002347 injection Methods 0.000 description 4
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
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- 238000000265 homogenisation Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 230000014759 maintenance of location Effects 0.000 description 2
- 239000012188 paraffin wax Substances 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 239000011819 refractory material Substances 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 230000008646 thermal stress Effects 0.000 description 2
- TVEXGJYMHHTVKP-UHFFFAOYSA-N 6-oxabicyclo[3.2.1]oct-3-en-7-one Chemical compound C1C2C(=O)OC1C=CC2 TVEXGJYMHHTVKP-UHFFFAOYSA-N 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
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Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/116—Refining the metal
- B22D11/117—Refining the metal by treating with gases
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/02—Linings
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
Abstract
The invention relates to a tundish turbulence controller, an installation method and an argon blowing method for steel for pipelines, which comprises a turbulence controller body, wherein the upper part of an inner cavity of the turbulence controller body is concentrically provided with a circular sleeve core along a longitudinal central line, the bottom of the inner cavity of the turbulence controller body is concentrically provided with an impact plate and a ventilating ring body from inside to outside along the longitudinal central line, a circular seam group and an air chamber box are arranged in the ventilating ring body from top to bottom, the air chamber box is positioned at the bottom of the circular seam and communicated with the circular seam, the bottom of the air chamber box is connected with an air inlet pipe, one end of the air inlet pipe is communicated with the air chamber box, and the other end of the air inlet pipe extends out of the side part of the turbulence controller body. The tundish turbulence controller can not only effectively reduce slag entrapment and inclusion entering a pouring area, but also effectively promote the uniformity of molten steel components and temperature; meanwhile, the bottleneck problem that a tundish turbulence controller is difficult to prolong the service life is solved, and the continuous casting time of a continuous casting tundish is greatly improved.
Description
Technical Field
The invention relates to a tundish turbulence controller, an installation method and an argon blowing method for pipeline steel, and belongs to the technical field of preparation of seabed oil and gas pipeline steel.
Background
In the development process of marine resources, particularly oil and gas resources, the importance of submarine pipelines is highlighted, and the severe marine environment puts higher quality requirements on submarine pipelines than on land pipelines. X80 steel is a high strength pipeline steel, but when applied in marine environments, there are higher demands for inclusion control in steel. The prior casting blank production process flow comprises the following steps: the method comprises the following steps of molten iron pretreatment, converter smelting, LF refining, RH refining, slab continuous casting, short continuous casting tundish continuous casting time, high inclusion control technical difficulty and high production cost.
The continuous casting tundish not only has the functions of stabilizing flow and shunting, but also plays an important role in removing molten steel inclusions, and homogenizing molten steel components and temperature, and the removing effect of the inclusions in the molten steel in the continuous casting tundish depends on the flowing state of the molten steel in the continuous casting tundish to a great extent. The existing continuous casting tundish metallurgy technology is generally provided with a flow control device such as a turbulence controller, a retaining wall and a dam in a tundish or is additionally provided with a tundish argon blowing metallurgy technology such as an air brick and an air curtain retaining wall, can improve the flowing state of molten steel in the continuous casting tundish and has a purification effect on the molten steel in the tundish.
Chinese patent document CN 103990786A (201410209232.8) discloses a device and a method for removing molten steel inclusions in a tundish of a double-flow slab caster, wherein a first dam, a second dam and a retaining wall are sequentially arranged between a water feeding port and a turbulence controller of one tundish at intervals in parallel, the height of the second dam is higher than that of the first dam, air curtain air bricks are symmetrically arranged between the turbulence controller and the retaining walls on two sides of the turbulence controller, the two air curtain air bricks are arranged on the periphery of the turbulence controller in an inverted eight shape, the device is used for completely removing the inclusions with the medium effective diameter larger than 50 mu m in the continuous casting billet, the number of the micro inclusions with the medium effective diameter smaller than 50 mu m in the continuous casting billet is reduced by more than 50% compared with the same ratio of the inclusions in the continuous casting billet produced by using the device with the turbulence controller, the retaining wall and the retaining wall arranged in the tundish of the double-flow slab caster, and compared with the device with which is simply provided with the turbulence controller in the tundish, The inclusion in the continuous casting billet produced by the air curtain ventilation device is reduced by more than 30 percent. However, the defects that bubble blind areas are formed at two ends of the air curtain air brick, the removal rate of impurities is influenced, the flow control device and the air curtain air brick in the tundish are separately arranged and installed, the construction difficulty and the working hours are increased, and the turnover use of the tundish is influenced exist. Chinese patent CN 103990787 a (201410209515.2) discloses a device and method for removing molten steel inclusions in a continuous casting tundish, which comprises a turbulence controller, an air curtain air brick, a retaining wall and a dam, wherein the air curtain air brick is positioned between the turbulence controller and the retaining wall and fixed on a permanent lining of a tundish bottom. The technology of the patent enables inclusions with the equivalent diameter larger than 50 mu m in the continuous casting billet to be basically removed, and the number of micro inclusions with the equivalent diameter smaller than 50 mu m in the continuous casting billet is reduced by more than 60% in a same ratio under the condition of using the combination of the turbulence controller, the retaining wall and the dam in a tundish, and is reduced by more than 30% in a same ratio under the condition of using the turbulence controller and the air curtain air brick in the tundish. However, the patented technology suffers from the following disadvantages: the argon flow is blown to air curtain air brick is big, and accuse class device, air curtain air brick separately set up, installation in the middle package, have increased the construction degree of difficulty and man-hour, influence middle package turnover and use.
It can be seen that the following problems or deficiencies exist in the production application of the existing tundish turbulence controller: the installation process is complex, increases the construction difficulty and working hours, and influences the turnover use of the tundish.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a tundish turbulence controller, an installation method and an argon blowing method for steel for pipelines. According to the invention, the annular circular seam is arranged in the inner cavity of the turbulence controller, and in the argon blowing process, the upward argon bubbles inhibit the downward speed of ladle pouring flow, so that the degree of turbulence formed by molten steel is weakened, slag entrapment and inclusion entering a pouring area are effectively reduced, the uniformity of molten steel components and temperature is more effectively promoted, and the cleanliness and homogenization of the molten steel are improved. Meanwhile, the circular seam interval is arranged, the bottleneck problem that a turbulence controller is difficult to prolong the service life is solved, and the continuous casting time of the continuous casting tundish is greatly prolonged.
In order to achieve the purpose, the invention adopts the following technical scheme:
a tundish turbulence controller comprises a turbulence controller body, wherein the upper part of an inner cavity of the turbulence controller body is concentrically provided with a circular sleeve core along a longitudinal central line, the bottom of the inner cavity of the turbulence controller body is concentrically provided with an impact plate and a ventilating ring body from inside to outside along the longitudinal central line,
a circular seam group and an air chamber box are arranged in the air permeable ring body from top to bottom, the air chamber box is located at the bottom of the circular seam and communicated with the circular seam, an air inlet pipe is connected to the bottom of the air chamber box, one end of the air inlet pipe is communicated with the air chamber box, and the other end of the air inlet pipe extends out of the side portion of the turbulence controller body.
The other end of the air inlet pipe sequentially penetrates through the bottom of the breathable ring body and the sleeve buried in the turbulence controller body from inside to outside.
Preferably, the circular seam group consists of 2-4 coaxial circular seams which are uniformly arranged and penetrate through the top surface of the breathable ring body, the width of each circular seam is 0.12-0.15 mm, the height h is 60-90 mm, and the distance a between every two adjacent circular seams is 10-20 mm. The distance b between the outer side of the circular seam group and the inner wall of the sleeve core is 30-50 mm. Each ring of circular seams is discontinuous, 4-6 circular seam intervals are uniformly distributed on each ring of continuous circular seams, the cross sections of the circular seam intervals are in a fan-shaped ring shape, and the central angle beta of the fan-shaped ring is 10-30 degrees.
Preferably, the air chamber box is annular as a whole, the longitudinal section of the air chamber box is rectangular, the width x of the rectangle is 30-50 mm, the height y of the rectangle is 20-30 mm, and the width x of the air chamber box is larger than the total width of the circular seam group. The top surface of the air chamber box is provided with a circular seam cloth channel, and the shape, the size and the arrangement of the circular seam cloth channel correspond to the shape, the size and the arrangement of the circular seam.
Preferably, the outer wall of one end of the air inlet pipe is welded on the inner surface of the lower bottom surface of the air chamber box, and the center line of the air inlet pipe points to the center of the turbulence controller body, so that the air inlet pipe can be laid along an angle line CB which leads to the outer end surface of the tundish impact area and two magnesium wall plates on the side surface, and finally extends out of the tundish edge.
Preferably, the air permeable ring body is cast and molded by adopting corundum-spinel castable, and the volume density of the air permeable ring body is more than or equal to 2.95g/cm 3 High-temperature bending strength is more than or equal to 12Mpa, high-temperature compressive strength is more than or equal to 60Mpa, and Al 2 O 3 + MgO content > 92%, Cr 2 O 3 The content is more than or equal to 4.0 percent.
Preferably, the impact plate is cylindrical as a whole, is formed by magnesium carbon isostatic pressing, and has the volume density of more than or equal to 2.92g/cm 3 The normal-temperature compressive strength is more than or equal to 45.4MPa, the normal-temperature flexural strength is more than or equal to 22.9MPa, the MgO content is more than or equal to 75 percent, and the C content is 14-15 percent. The height of the impact plate is the same as the height H of the breathable ring body.
Preferably, the sleeve core is in a circular truncated cone shape with a large upper part and a small lower part, a cylindrical through hole is formed in the middle of the sleeve core, and the sleeve core is produced by adopting a magnesium prefabricated part and a medium-temperature sintering process.
Preferably, the turbulence controller body is formed by casting magnesium spinel castable and is sintered at medium temperature. The magnesium spinel castable is produced by the prior art, the MgO content is more than or equal to 71 wt%, and the volume density is more than or equal to 3.03g/cm 3 The breaking strength (1500 ℃) is more than or equal to 9 Mpa.
According to the invention, a layer of paraffin is preferably coated on the working surface of the circular seam, so that the air permeable surface is protected, and the problems of poor circular seam air permeability and the like caused by water seepage and material seepage are prevented.
The turbulence controller body is internally and annularly provided with annular seam groups, each annular seam comprises 2-4 annular seams, the width of each annular seam is 0.12-0.15 mm, the height h of each annular seam is 60-90 mm, the distance a between every two adjacent annular seams is 10-20 mm, the distance b between the outermost side of each annular seam group and the inner wall of the sleeve core is 30-50 mm, the annular seams are discontinuous, each annular seam is provided with 4-6 uniformly distributed annular seam intervals, each annular seam interval is in a fan-shaped annular shape, and the fan-shaped angle beta is 10-30 degrees. The design is verified by a person skilled in the art through a large number of numerical physical simulation research experiments and industrial application experiments, and an unexpected technical effect is achieved.
In a simulation research experiment, the inventor unexpectedly finds that the circular annular ring seam group is arranged in the turbulence controller body, bubbles moving upwards are generated after air blowing, and an annular air curtain barrier can be formed in the turbulence controller. When the large packet of injection flow enters the turbulence controller, the bubbles can be broken into more and smaller bubbles, and meanwhile, the floating bubbles inhibit the downward speed of the injection flow. The two interact, the degree of the molten steel forming turbulence is weakened, the flowing state of the molten steel in the tundish is improved, the retention time of the molten steel in the tundish is prolonged, and the floating of inclusions is promoted. Effectively reduces the slag entrapment and the inclusion entering the pouring area, and more effectively promotes the uniformity of the molten steel components and the temperature. The width and the number of the circular seams, the distance a between the adjacent circular seams and the distance b between the outer sides of the circular seams and the inner wall of the sleeve core of the turbulent flow controller have direct influence on the argon blowing effect. Through a large number of research experiments and application tests, the optimal width and the number of the circular seams, the distance a between adjacent circular seams and the distance b between the outer sides of the circular seams and the inner wall of the sleeve core are determined through research. Meanwhile, in an industrial application test, the technical scheme that the circular seams are discontinuous and the circular seam intervals are uniformly distributed is found out unexpectedly, so that the problems that thermal stress is concentrated at the circular seams and peeling is caused can be effectively solved, and the service life of the breathable ring body can be greatly prolonged. Through a large number of researches and application tests, the optimal distribution quantity, shape and size of the annular gap intervals are researched and determined, the height h of the annular gap is researched and determined to be 60-90 mm according to the erosion and scouring condition analysis of the turbulence controller, and the technical scheme that the annular impact plate is arranged at the bottom of the inner cavity of the turbulence controller body is researched and designed, so that the integral service life of the turbulence controller is prolonged to 24-30 h, and the unexpected technical effect is achieved. Compared with other types of air-permeable exchange pieces arranged in the turbulence controller, the annular seam group has the advantages of longer service life and high blow-through rate.
The invention also provides an installation method of the tundish turbulence controller, which comprises the following steps:
(1) after the construction of the tundish working lining is finished, placing the turbulence controller body on the tundish impact area working lining, and leading the air inlet pipe to an outer end face of the tundish impact area and an angle line CB of two magnesium wallboards on the side face;
(2) connecting and laying an air inlet pipeline: according to the size of a turn and the hot-bending of an air inlet pipeline, after the air inlet pipeline is connected with an air inlet pipe, the air inlet pipeline is laid along the outer end face of an impact area of a tundish and the corner line CB of two magnesium wall plates on the side face, and finally extends out of the edge of the tundish, and the extended air inlet pipeline is fixed on a tundish pressing plate;
(3) installing and fixing a turbulence controller body, and filling a gap between a tundish impact area working lining and the turbulence controller body, namely a filling layer, by using waste materials with granularity less than 3mm which are removed after the tundish working lining is removed;
(4) the magnesium wallboard is arranged at the upper part of the turbulence controller body, magnesium coating is adopted to coat the joint of the magnesium wallboard and each part of the turbulence controller body into a streamline shape, and the exposed air inlet pipeline part is coated into an outer layer of the streamline coating. The installation of the long-service-life continuous casting tundish turbulence controller with the molten steel purification function is completed, and the tundish working lining can be used online after being baked.
The air inlet pipe and the air inlet pipeline are made of heat-resistant stainless steel round pipes, and the outer diameters of the air inlet pipe and the air inlet pipeline are 10-12 mm. The magnesium coating is a conventional refractory material and is a commercially available product.
An argon blowing metallurgy method for producing pipeline steel by using the tundish turbulence controller comprises the following steps:
before a continuous casting tundish is baked, a gas inlet pipeline is connected with an external argon gas source, argon is introduced after the liquid level of molten steel in the continuous casting tundish reaches a normal liquid level, the flow of the argon is controlled at 8-12 NL/min, and the argon is stopped blowing after a continuous casting ladle is stopped.
According to the invention, the flow of the blown argon has a direct influence on the argon blowing effect, and through a large number of researches and application experiments, the best argon flow control is determined to be 8-12 NL/min.
The invention has the beneficial effects that:
1) the inner circle of the tundish turbulence controller body provided by the invention is annularly provided with the annular seam group consisting of a plurality of annular seams, and in the argon blowing process, the argon bubbles move upwards to form an annular air curtain barrier in the turbulence controller. The large packet of injected flow enters the turbulence controller, which "breaks up" the argon bubbles, forming more and smaller argon bubbles. Meanwhile, the floating argon bubbles can also inhibit the downward speed of the injection flow, and the interaction of the argon bubbles and the injection flow weakens the degree of the turbulent flow formed by the molten steel and improves the flowing state of the molten steel in the tundish. The device can prolong the retention time of the molten steel in the tundish, promote the floating of inclusions, reduce slag entrapment and the entering of inclusions into a pouring area, more effectively promote the uniformity of the components and the temperature of the molten steel, and improve the cleanliness and the homogenization of the molten steel. The invention is applied to steel X80 for a pouring production line of a slab continuous casting tundish, the number of inclusions in a continuous casting billet is reduced by 25 percent compared with that of the prior art CN 103990786A (201410209232.8), and the normal argon blowing flow is reduced by more than 60 percent compared with the normal argon blowing flow.
2) The annular seams in the air-permeable ring body of the tundish turbulence controller are discontinuous, 4-6 annular seam intervals are uniformly distributed in each annular seam, the annular seam intervals are in a fan-shaped annular shape, and the fan-shaped annular angle beta is 10-30 degrees. The arrangement can effectively eliminate the problems of transverse breakage and peeling of the air brick caused by the concentration of thermal stress at the circular seam. The invention solves the bottleneck problem of prolonging the service life of the tundish turbulence controller, and compared with the prior art, the continuous casting time of the tundish of the invention is improved by 10h compared with the CN 103990786A (201410209232.8) of the prior art.
3) The top surface of the air chamber box of the tundish turbulence controller is provided with the circular seam cloth channel, the shape, the size and the arrangement of the circular seam cloth channel correspond to the shape, the size and the arrangement of the circular seam, the circular seam cloth channel is used for internally inserting and internally fixing the lower end of the plastic strip for forming the circular seam, and is matched with the externally inserting and externally fixing at the upper end of the plastic strip for forming the circular seam in the same corresponding arrangement, so that the preparation mold and the preparation process of the continuous casting tundish turbulence controller are simplified.
4) According to the installation method of the tundish turbulence controller provided by the invention, the air inlet pipeline is laid along the outer end face of the tundish impact area and the corner line CB of the two magnesium wallboards on the side face, and the laying process is simple, safe and reliable. The problem of current air inlet pipeline lay insecure, easily cause the safe problems such as tundish work lining wearing steel, air inlet pipeline melting loss is solved, the fail safe nature of air inlet pipeline and tundish work lining has been improved.
Drawings
FIG. 1 is a cross-sectional view of a tundish turbulence controller according to an embodiment of the present invention.
FIG. 2 is a top view of a tundish turbulence controller according to an embodiment of the present invention.
FIG. 3 is a schematic diagram of the structure of the air chamber box and its circular seam channel of the tundish turbulence controller according to the embodiment of the present invention.
FIG. 4 is a top view of a tundish turbulence controller installation as described in an embodiment of the invention.
FIG. 5 is an enlarged partial view of tundish turbulence controller installation F in an embodiment of the present invention.
FIG. 6 is a cross-sectional view A-A of the tundish turbulence controller installation in an embodiment of the invention.
In the drawings, 1. a turbulence controller body; 2. sleeving a core; 3. a circular seam group; 4. a gas permeable ring body; 5. an impact plate; 6. an air chamber box; 7. an air inlet pipe; 8. a sleeve; 9. the circular seams are spaced; 10. circularly sewing a cloth path; 11. an air intake line; 12. a magnesium wallboard; 13. a tundish working lining; 14. and (5) filling the layer.
Detailed Description
The present invention will be further described with reference to the following drawings and examples, but the scope of the present invention is not limited thereto.
The magnesium coating in the examples is a conventional refractory, a commercially available product.
Example 1:
a continuous casting tundish turbulence controller is structurally shown in figures 1-6 and comprises a turbulence controller body 1, wherein a circular ring-shaped sleeve core 2 is concentrically arranged at the upper part of an inner cavity of the turbulence controller body 1 along a longitudinal central line, a cylindrical impact plate 5 and a ventilating ring body 4 are concentrically arranged at the bottom of the inner cavity of the turbulence controller body 1 from inside to outside along the longitudinal central line in sequence,
top-down is provided with circumferential weld group 3, air chamber box 6 in the ventilative ring body 4, air chamber box 6 be located the bottom of circumferential weld group 3 to with the circumferential weld intercommunication, the bottom of air chamber box 6 is connected with intake pipe 7, the one end and the air chamber box 6 intercommunication of intake pipe 7, the other end is by interior bottom, the sleeve pipe 8 that turbulence controller body 1 was buried underground that outside to pass ventilative ring body 4 in proper order, stretches out from the lateral part of turbulence controller body.
The circular seam group 3 is composed of 3 coaxial circular seams which are uniformly arranged, the circular seams penetrate through the top surface of the breathable ring body 4, the width of each circular seam is 0.14mm, the height h of each circular seam is 70mm, the distance a between every two adjacent circular seams is 15mm, and the distance b between the outer side of the circular seam group and the inner wall of the sleeve core 2 is 40 mm. The circular seam is discontinuous and is composed of a plurality of circular slits which penetrate through the top surface of the air permeable ring body 4, and the circular slits are uniformly distributed along the circumference by taking the longitudinal center line of the inner bottom as the center. Each ring of circular seams is provided with 6 circular seam intervals 9 which are uniformly arranged, the cross sections of the circular seam intervals 9 are in a fan-shaped ring shape, and the central angle beta of the fan-shaped ring shape is 20 degrees. The circular seam group 3 is positioned at the central part of the breathable ring body 4, namely, the distance from the outermost side of the circular seam group 3 to the outer wall of the breathable ring body 4 is the same as the distance from the innermost side of the circular seam group 3 to the outer wall of the breathable ring body 4.
The whole air chamber box 6 is circular, the longitudinal section of the air chamber box 6 is rectangular, the width x of the rectangle is 40mm, the height y of the rectangle is 25mm, the top surface of the air chamber box 6 is provided with a circular seam cloth channel 10, and the shape, the size and the arrangement of the circular seam cloth channel 10 correspond to the shape, the size and the arrangement of the circular seam 3. The circular seam cloth path can be used for internal insertion and internal fixation of the lower end of the plastic strip for forming the circular seam. The breathable ring body 4 with the annular seam group is provided with a burnout plastic strip in the casting molding process, the plastic strip is carbonized to disappear and form a slit in the casting molding process, the plastic strip is arranged at the corresponding slit, and the upper end and the lower end of the casting molding die are provided with slit plates for inserting and fixing the plastic strip. The preparation and forming process of the slit is the prior art.
The outer wall of intake pipe 7 one end welds on the internal surface of bottom surface under the air chamber box 6, and the central line of intake pipe 7 points to the center of turbulence controller body 1 for intake pipe 7 leads to the outer terminal surface of middle package impact zone and the angular line CB of two magnesian wallboards 12 of side, and lays along angular line CB, and it is along stretching out from middle package at last.
The air permeable ring body 4 is cast and molded by adopting corundum-spinel castable, and the volume density is more than or equal to 2.95g/cm 3 High-temperature bending strength is more than or equal to 12Mpa, high-temperature compressive strength is more than or equal to 60Mpa, and Al 2 O 3 + MgO content > 92%, Cr 2 O 3 The content is more than or equal to 4.0 percent.
The whole impact plate 8 is cylindrical, is formed by magnesium carbon isostatic pressing, and has the volume density of more than or equal to 2.92g/cm 3 The normal-temperature compressive strength is more than or equal to 45.4Mpa, the normal-temperature flexural strength is more than or equal to 22.9Mpa, the MgO content is more than or equal to 75 percent, and the C content is 14-15 percent. The height of the impact plate is the same as the height H of the air permeable ring body 4, and H + y is 70mm +25 mm-95 mm.
The whole sleeve core 2 is in a circular truncated cone shape with a large upper part and a small lower part, a cylindrical through hole is formed in the middle of the sleeve core, and the sleeve core is produced by adopting a magnesium prefabricated part and a medium-temperature sintering process.
The turbulence controller body 1 is formed by casting magnesium spinel castable and is sintered at medium temperature. The magnesium spinel castable is produced by the prior art, and has MgO content more than or equal to 71 wt% and volume density more than or equal to 3.03g/cm 3 The breaking strength (1500 ℃) is more than or equal to 9 Mpa.
A layer of paraffin is coated on the working surface of the circular seam, so that the breathable surface is protected, and the problems of poor circular seam breathability and the like caused by water seepage and seepage are solved.
The installation method of the continuous casting tundish turbulence controller comprises the following steps:
(1) after the construction of the tundish working lining 13 is finished, the turbulence controller body 1 is placed on the tundish impact area working lining 13, and the air inlet pipe 7 is led to the outer end face of the tundish impact area and the corner line CB of the two magnesium wallboards 12 on the side face;
(2) connecting and laying an air inlet pipeline 11: according to the turning size and the hot-turning air inlet pipeline 11, after the air inlet pipeline 11 is connected with the air inlet pipe 7, the air inlet pipeline 11 is laid along the outer end face of the impact area of the tundish and the corner line CB of the two magnesium wall plates 12 on the side face, and finally extends out of the edge of the tundish, and the extended air inlet pipeline 11 is fixed on the tundish pressing plate in an iron wire fastening or steel bar welding mode;
(3) installing and fixing the turbulence controller body 1, and filling the filling layer 14 with the removed waste material with the granularity less than 3mm after the tundish working lining is removed;
(4) the magnesium wallboard 12 is arranged on the upper part of the turbulence controller body 1, magnesium coating is adopted to coat the joint of the magnesium wallboard 12 and each part of the turbulence controller body 1 into a streamline shape, and the exposed part of the air inlet pipeline 11 is coated with an outer layer of the streamline coating. The installation of the long-service-life continuous casting tundish turbulence controller with the molten steel purification function is completed, and the tundish working lining 13 can be used online after being baked.
The air inlet pipe 7 and the air inlet pipeline 11 are made of heat-resistant stainless steel round pipes, and the outer diameter of the air inlet pipe is 11 mm. The magnesium coating is a conventional refractory material and is a commercially available product.
An argon blowing metallurgy method for steel X80 for a continuous casting tundish turbulence controller production line, which comprises the following steps:
before the continuous casting tundish is baked, the air inlet pipeline 11 is connected with an external argon source, argon is introduced after the liquid level of molten steel in the continuous casting tundish reaches a normal liquid level, the flow of the argon is controlled at 10NL/min, and the argon is stopped from being blown in after the continuous casting tundish stops casting.
Example 2
A continuous casting tundish turbulence controller as in example 1, except that:
the number of the circular seams of the circular seam group 3 is 2, the width of each circular seam is 0.15mm, the height h of each circular seam is 60mm, the distance a between every two adjacent circular seams is 20mm, and the distance b between the outer side of the circular seam group 3 and the inner wall of the sleeve core 2 is 30 mm. Each annular seam is provided with 4 evenly distributed annular seam intervals 9, and the sector annular angle beta is 10 degrees.
The width x of the air cell box 6 is 30mm, and the height y is 20 mm. The outer diameters of the air inlet pipe 7 and the air inlet pipeline 11 are both 10 mm.
An argon blowing metallurgical method for producing pipeline steel X80 by using the continuous casting tundish turbulence controller of the embodiment comprises the following steps:
before the continuous casting tundish is baked, the air inlet pipeline 11 is connected with an external argon source, argon is introduced after the liquid level of molten steel in the continuous casting tundish reaches a normal liquid level, the flow of the argon is controlled at 8NL/min, and the argon is stopped from being blown in after the continuous casting tundish stops casting.
Example 3
A continuous casting tundish turbulence controller as in example 1, except that:
the number of the circular seams of the circular seam group 3 is 4, the width of each circular seam is 0.12mm, the height h of each circular seam is 90mm, the distance a between every two adjacent circular seams is 10mm, and the distance b between the outer side of the circular seam group 3 and the inner wall of the sleeve core 2 is 50 mm. Each ring of circular seams is provided with 6 uniformly distributed circular seam intervals 9, and the fan-shaped angle beta is 30 degrees.
The width x of the air cell box 6 is 50mm, and the height y is 30 mm. The outer diameters of the air inlet pipe 7 and the air inlet pipeline 11 are both 12 mm.
An argon blowing metallurgical method for producing pipeline steel X80 by using the continuous casting tundish turbulence controller of the embodiment comprises the following steps:
before the continuous casting tundish is baked, the air inlet pipeline 11 is connected with an external argon source, argon is introduced after the liquid level of molten steel in the continuous casting tundish reaches a normal liquid level, the flow of the argon is controlled at 12NL/min, and after the continuous casting tundish stops casting, the argon is stopped blowing in.
The multifunctional continuous casting tundish turbulence controller can be used for various continuous casting tundishes, is particularly suitable for steel types with strict inclusion control, and is preferably but not limited to pipeline steel X42-X80.
Comparative example 1
Referring to Chinese patent document CN 103990786A (201410209232.8), the device for removing the molten steel inclusion in the tundish of the double-flow slab casting machine and the method for removing the molten steel inclusion in the tundish of the double-flow slab casting machine in embodiment 1 and embodiment 4, the argon blowing flow of the air curtain air bricks is controlled at 30NL/min when molten steel is normally poured in the tundish.
For the device and the method for removing the molten steel inclusions in the tundish of the dual-flow slab caster in the embodiments 1 to 3 and the comparative example 1, the device and the method are used for application comparative analysis of pipeline steel X80 on the tundish of the slab caster in a steel plant of the Laiwu Steel group Yinshan type Steel Co., Ltd, casting blank samples are respectively taken, the length and the width of the samples are both 30mm, the number of the inclusions is detected and analyzed by adopting an electron microscope, and the comparative result is shown in Table 1.
TABLE 1
Through the comparison of the data in the table, the invention reduces the quantity of inclusions in the continuous casting billet of the pipeline steel X80 by 25 percent compared with the prior art CN 103990786A (201410209232.8), reduces the normal argon blowing flow by more than 60 percent compared with the prior art, and improves the continuous casting time of the tundish by 10 hours compared with the prior art.
Claims (10)
1. A continuous casting tundish turbulence controller is characterized by comprising a turbulence controller body (1), wherein the upper part of an inner cavity of the turbulence controller body (1) is concentrically provided with a circular ring-shaped sleeve core (2) along a longitudinal central line, the bottom of the inner cavity of the turbulence controller body (1) is concentrically provided with an impact plate (5) and a ventilating ring body (4) from inside to outside along the longitudinal central line,
top-down is provided with circumferential weld group (3), air chamber box (6) in ventilative ring body (4), air chamber box (6) be located the bottom of circumferential weld (3) to with the circumferential weld intercommunication, the bottom of air chamber box (6) is connected with intake pipe (7), the one end and the air chamber box (6) intercommunication of intake pipe (7), the other end stretches out from the lateral part of turbulence controller body (1).
2. A tundish turbulence controller according to claim 1, characterized in that the set of circumferential seams (3) consists of 2-4 concentric circumferential seams uniformly arranged across the top surface of the permeable ring body (4).
3. The tundish turbulence controller of claim 1, wherein the width of each annular seam is 0.12-0.15 mm, the height h of the annular seam is 60-90 mm, and the distance a between two adjacent annular seams is 10-20 mm.
4. A tundish turbulence controller according to claim 1, wherein each circumferential slot is discontinuous, each circumferential slot is provided with 4-6 circumferential slot spaces (9) arranged uniformly, the circumferential slot spaces (9) are of sector-annular shape in cross-section, and the sector-annular central angle β is 10-30 °.
5. A tundish turbulence controller according to claim 1, characterised in that the width x of the plenum box (6) is greater than the total width of the set of circumferential seams (3);
the whole air chamber box (6) is annular, the longitudinal section of the air chamber box (6) is rectangular, the width x of the rectangle is 30-50 mm, and the height y of the rectangle is 20-30 mm;
the top surface of the air chamber box (6) is provided with a circular seam cloth channel (10), and the shape, the size and the arrangement of the circular seam cloth channel correspond to the shape, the size and the arrangement of the circular seam (3).
6. A tundish turbulence controller according to claim 1, characterized in that the impingement plate (5) is generally cylindrical and has the same height as the height H of the breather ring body (4).
7. Tundish turbulence controller according to claim 1, characterized in that the gas permeable ring body (4) is cast from a corundum-spinel castable with a bulk density of 2.95g/cm or more 3 High-temperature rupture strength of 12MPa or more, high-temperature compression strength of 60MPa or more, Al 2 O 3 + MgO contentThe content is more than or equal to 92 percent, Cr 2 O 3 The content is more than or equal to 4.0 percent;
the impact plate (5) is formed by magnesium carbon isostatic pressing, and the volume density is more than or equal to 2.92g/cm 3 The normal-temperature compressive strength is more than or equal to 45.4Mpa, the normal-temperature flexural strength is more than or equal to 22.9Mpa, the MgO content is more than or equal to 75 percent, and the C content is 14-15 percent;
the whole sleeve core (2) is in a round table shape with a large upper part and a small lower part, a cylindrical through hole is arranged in the middle, and the sleeve core is produced by adopting a magnesium prefabricated part and a medium-temperature firing process;
the turbulence controller body (1) is molded by casting with magnesium spinel castable and is sintered at medium temperature; the magnesium spinel castable is produced by the prior art, the MgO content is more than or equal to 71 wt%, and the volume density is more than or equal to 3.03g/cm 3 The breaking strength (1500 ℃) is more than or equal to 9 Mpa.
8. A method for installing a continuous casting tundish turbulence controller is characterized by comprising the following steps:
1) after the construction of the tundish working lining (13) is finished, placing the turbulence controller body (1) on the tundish impact area working lining (13), and leading the air inlet pipe (7) to an angle line CB of the outer end face of the tundish impact area and two magnesium wall plates (12) on the side face;
2) connecting and laying an air inlet pipeline (11): according to the turning size and the hot-turning air inlet pipeline, after the air inlet pipeline (11) is connected with an air inlet pipe (7), the air inlet pipeline (11) is laid along the outer end face of the impact area of the tundish and the corner line CB of the two magnesium wall plates (12) on the side face, and finally extends out of the tundish edge, and the extended air inlet pipeline (11) is fixed on the tundish pressing plate;
3) installing and fixing a turbulence controller body (1), and filling a gap between a tundish impact area working lining (13) and the turbulence controller body (1), namely a filling layer (14), with a waste material with granularity less than 3mm removed after the tundish working lining is removed;
4) the magnesium wallboard (12) is arranged at the upper part of the turbulence controller body (1), magnesium coating is adopted to coat the joint of the magnesium wallboard (12) and each part of the turbulence controller body (1) into a streamline shape, and the exposed part of the air inlet pipeline (11) is coated into an outer layer of the streamline coating.
9. The mounting method according to claim 8, wherein the air inlet pipe (7) and the air inlet pipeline (11) are made of heat-resistant stainless steel round pipes, and the outer diameters of the heat-resistant stainless steel round pipes are 10-12 mm.
10. An argon blowing metallurgical method for producing pipeline steel by using the tundish turbulence controller as claimed in any one of claims 1 to 7, which is characterized by comprising the following steps:
before the continuous casting tundish is baked, the air inlet pipeline (11) is connected with an external argon source, argon is introduced after the liquid level of molten steel in the continuous casting tundish reaches a normal liquid level, the flow of the argon is controlled at 8-12 NL/min, and the argon stops being blown in after the continuous casting tundish stops casting.
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| CN117862430A (en) * | 2023-12-22 | 2024-04-12 | 鞍钢股份有限公司 | Device and method for removing inclusions in molten steel in tundish |
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