Internal conical argon protection ring and preparation method thereof

Abstract

The invention relates to an inner conical argon protection ring and a preparation method thereof, belongs to the technical field of smelting industry, and solves the problems that an existing argon protection ring is poor in air isolation effect and poor in molten steel suction control effect when a steel ingot is poured. The inner conical argon protection ring comprises an inner sleeve, an outer sleeve and a main pipe which are sequentially sleeved from inside to outside, the main pipe is a hollow annular pipe and is communicated with the outer sleeve through an air inlet pipe; the inner sleeve is a conical hollow sleeve and is communicated with the outer sleeve through an air outlet hole formed in the conical surface; the top ends of the inner sleeve and the outer sleeve are connected through a cover plate, the bottom end of the inner sleeve is connected with the inner wall side of the outer sleeve through a middle plate, and an air chamber is defined by the outer wall of the inner sleeve, the inner wall of the outer sleeve, the lower end face of the cover plate and the upper end face of the middle plate. According to the argon protection ring, the molten steel suction control effect is improved.

Description

Technical Field

[0001] The invention relates to the technical field of smelting industry, and in particular to an inner cone argon protection ring and a preparation method thereof. Background Art

[0002] In the die casting process, ingot pouring is a very important production link, which can easily cause secondary oxidation and air absorption of molten steel. Common ingot pouring technologies include vacuum pouring and atmospheric pouring. At present, the maximum production capacity of vacuum pouring ingots can reach 715 tons, while the factors that limit the production capacity of atmospheric pouring ingots include the anti-scouring ability of the refractory materials of the pouring system and the control of the gas content in the atmospheric pouring ingots.

[0003] With the improvement of the vacuum system capacity in the steel refining process, the hydrogen content can be controlled below 1ppm during the refining stage, which brings an opportunity for the large-scale production of atmospheric casting steel ingots. Atmospheric casting steel ingot casting technology has great advantages in removing inclusions, mainly because when the molten steel is poured, it flows from the bottom of the ingot to the top of the ingot, which is conducive to the floating of inclusions in the molten steel; at the same time, casting the ingot can reduce the casting temperature and reduce the consumption of refractory materials and metallurgical auxiliary tools.

[0004] Avoiding molten steel from inhaling air during the atmospheric pouring process is crucial to controlling the gas content in the ingot; the key to avoiding molten steel from inhaling air is the argon protection in the ladle injection area, but the existing cylindrical argon protection ring is difficult to form a certain positive pressure environment in the injection area, resulting in poor argon gas isolation and poor control of molten steel inhalation. Therefore, it is urgent to improve the existing argon protection equipment to improve its air isolation effect. Summary of the invention

[0005] In view of the above analysis, an embodiment of the present invention aims to provide an inner conical argon protection ring and a preparation method thereof, so as to solve the problem that the existing argon protection equipment has poor air isolation effect and poor effect of controlling molten steel intake during the atmospheric pouring of steel ingots.

[0006] In one aspect, the present invention provides an inner conical argon protection ring, the inner conical argon protection ring comprising an inner sleeve, an outer sleeve and a main pipe which are sequentially sleeved from the inside to the outside;

[0007] The main pipe is a hollow annular pipe, which is connected to the outer sleeve through the air inlet pipe;

[0008] The inner sleeve is a conical hollow sleeve, which is connected to the outer sleeve through an air outlet hole provided on the conical surface;

[0009] The top ends of the inner sleeve and the outer sleeve are connected through a cover plate, the bottom end of the inner sleeve is connected to the inner wall side of the outer sleeve through a middle plate, and the outer wall of the inner sleeve, the inner wall of the outer sleeve, the lower end face of the cover plate and the upper end face of the middle plate together form an air chamber.

[0010] Furthermore, the air outlet holes formed on the conical surface of the inner sleeve include upper air outlet holes and lower air outlet holes, and the upper air outlet holes and the lower air outlet holes have different opening directions.

[0011] Furthermore, the number of the upper layer air outlet holes and the number of the lower layer air outlet holes are the same, both N, and the value range of N is 4 to 16;

[0012] The upper air outlet holes and the lower air outlet holes are evenly distributed around the circumference of the inner sleeve.

[0013] Furthermore, the upper air outlet holes are 1 to 5 mm away from the top end surface of the inner sleeve, and the lower air outlet holes are 1 to 5 mm away from the bottom end surface of the inner sleeve.

[0014] Furthermore, the top surface of the inner sleeve is a horizontal plane, the upper air outlet hole maintains an angle α with the top surface of the inner sleeve, and the minimum value of α is min Satisfaction: sinα min =2×D 孔 / (D 上 -D 外 );

[0015] Wherein, α is the angle between the upper air outlet and the horizontal plane of the top surface of the inner sleeve, °;

[0016] D 孔 is the diameter of the air outlet, mm;

[0017] D 上 is the inner diameter of the upper opening of the inner sleeve, mm;

[0018] D 外 is the outer diameter of the ladle nozzle refractory, mm.

[0019] Furthermore, the bottom end surface of the inner sleeve is a horizontal plane, and the lower layer air outlet hole maintains an angle β with the horizontal plane of the bottom end surface of the inner sleeve, and the minimum value β of β min Satisfies: sinβ min =2×D 孔 / (D 下 -D 砖 );

[0020] Wherein, β is the angle between the lower air outlet and the horizontal plane of the bottom end surface of the inner sleeve, °;

[0021] D 孔 is the diameter of the air outlet, mm;

[0022] D 下 is the inner diameter of the lower opening of the inner sleeve, mm;

[0023] D 砖 is the outer diameter of the basin brick inside the center injection pipe, mm.

[0024] Furthermore, the cover plate is an annular plate with a hole in the middle, and the outer diameter of the cover plate is equal to the outer diameter of the outer sleeve.

[0025] Furthermore, the height of the outer sleeve is 1.5 to 2.0 times the height of the inner sleeve.

[0026] Furthermore, when the steel ingot is cast using double-layer slide casting, the inner sleeve satisfies: D 上 ≥D 外 And D 上 ≥L+D 水 / 2;

[0027] Among them, D 上 is the inner diameter of the upper opening of the inner sleeve, mm;

[0028] D 外 is the outer diameter of the ladle nozzle refractory, mm;

[0029] L is the sliding stroke of the nozzle when casting with double-layer slide plates, mm;

[0030] D 水 is the diameter of the ladle nozzle, mm;

[0031] When the ingot is cast using three-layer slide casting, the inner sleeve meets the following requirements: 下 >D 砖 ;

[0032] Among them, D 下 is the inner diameter of the lower opening of the inner sleeve, mm;

[0033] D 砖 is the outer diameter of the basin brick inside the center injection pipe, mm.

[0034] On the other hand, the present invention also provides a method for preparing an inner conical argon protection ring, which is used to prepare the inner conical argon protection ring according to any one of claims 1-9.

[0035] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0036] 1. Compared with the existing argon protection ring using a cylindrical inner sleeve, the present invention forms a certain positive pressure environment in the injection area through the design of an inner conical inner sleeve, solving the problem that the existing argon protection equipment has poor air isolation effect and poor effect of controlling molten steel suction.

[0037] 2. The present invention ensures good argon protection effect and positive pressure environment of the gas chamber by evenly distributing gas outlet holes that meet angle requirements on the inner sleeve of the inner conical argon protection ring, while avoiding direct impact on the molten steel flow and improving the effect of controlling the molten steel suction.

[0038] 3. The present invention can avoid the argon gas in the air inlet pipe from directly impacting the air outlet holes by staggering the air inlet pipe and the air outlet holes of the inner conical argon protection ring, thereby causing the argon pressure of some air outlet holes to be greater than that of other air outlet holes, affecting the uniform distribution of the positive pressure environment in the air chamber; thus ensuring the uniform distribution of the positive pressure environment in the air chamber and improving the effect of controlling the air intake of molten steel.

[0039] In the present invention, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present invention will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The drawings are only for the purpose of illustrating specific embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings.

[0041] Figure 1 It is a cross-sectional schematic diagram of the inner conical argon protection ring structure of the present invention;

[0042] Figure 2 It is a cross-sectional view of the inner conical argon protection ring structure of the present invention taken along the AA direction;

[0043] Figure 3 for Figure 1 A schematic diagram of the structure of the inner conical argon protection ring when in use;

[0044] Figure 4 This is a schematic cross-sectional view of the existing cylindrical argon protection ring structure in Comparative Example 1 of the present invention.

[0045] Reference numerals:

[0046] 1-cover plate; 2-inner sleeve; 3-outer sleeve; 4-middle plate; 5-inlet pipe; 6-air chamber; 7-air outlet; 8-main pipe; 9-ladle water outlet; 10-ladle bottom; 11-asbestos board; 12-vent pipe; AA-cutting direction;

[0047] D 水 - diameter of the ladle nozzle; L - sliding stroke of the nozzle when casting with double-layer slide plates; D 外 -Outer diameter of ladle nozzle refractory material; D 砖 -Outer diameter of basin brick; D中注管 -Outer diameter of the center injection pipe;

[0048] H 外 -Outer sleeve height; H 内 -Inner sleeve height; D 上 -Inner diameter of the inner sleeve top; D 下 -Inner diameter of the lower opening of the inner sleeve; D 孔 - diameter of the air outlet hole; α- the angle maintained by the air outlet holes on the upper layer of the inner sleeve and the horizontal plane; β- the angle maintained by the air outlet holes on the lower layer of the inner sleeve and the horizontal plane. DETAILED DESCRIPTION

[0049] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0050] The present invention provides an inner conical argon protection ring, comprising an inner sleeve, an outer sleeve and a main pipe which are sequentially sleeved from the inside to the outside;

[0051] The main pipe is a hollow annular pipe, which is connected to the outer sleeve through the air inlet pipe;

[0052] The inner sleeve is a conical hollow sleeve, which is connected to the outer sleeve through an air outlet hole provided on the conical surface;

[0053] The top ends of the inner sleeve and the outer sleeve are connected through a cover plate, the bottom end of the inner sleeve is connected to the inner wall side of the outer sleeve through a middle plate, and the outer wall of the inner sleeve, the inner wall of the outer sleeve, the lower end face of the cover plate and the upper end face of the middle plate together form an air chamber.

[0054] Figure 1 It is a cross-sectional schematic diagram of the inner conical argon protection ring structure of the present invention; Figure 2 A cross-sectional view of the inner conical argon protection ring structure of the present invention taken along the AA direction.

[0055] A vent pipe is provided outside the main pipe, and the vent pipe is connected to the main pipe by welding for introducing argon gas;

[0056] The outer sleeve is a circular hollow sleeve, and the air inlet pipes are evenly distributed on the outside thereof. The two ends of the air inlet pipes are connected with the outer sleeve and the main pipe respectively by welding.

[0057] Specifically, the inner diameter of the main pipe is consistent with the outer diameter of the ventilation pipe. To ensure the ventilation volume, the inner diameter of the main pipe is preferably 20-30 mm, and the wall thickness of the main pipe is 1-2 mm to ensure sufficient strength. Steel material is selected to ensure that it can be connected to the intake pipe by welding.

[0058] Specifically, the outer sleeve is made of rolled steel plate, and the inner diameter of the outer sleeve is 10 to 25 mm larger than the outer diameter of the center injection tube; the wall thickness of the outer sleeve is 2 to 3 mm; the height of the outer sleeve is 1.5 to 2.0 times the height of the inner sleeve. When in use, the outer sleeve needs to be fitted onto the center injection tube, so the inner diameter of the outer sleeve needs to retain an assembly margin of 10 to 25 mm relative to the outer diameter of the center injection tube for easy assembly during use; the wall thickness of the outer sleeve is 2 to 3 mm, which can ensure that the outer sleeve has sufficient strength and is easy to reuse; the height of the outer sleeve is 1.5 to 2.0 times the height of the inner sleeve, which can ensure the stability of the outer sleeve after being fitted onto the center injection tube.

[0059] Specifically, the inner sleeve is rolled from a steel plate, and the height of the inner sleeve needs to take into account the gap between the bottom of the ladle water inlet and the top of the center pouring pipe. In the present invention, the height of the inner sleeve is 200 to 300 mm. If the height of the inner sleeve is too high, the distance between the ladle water outlet and the inner basin brick of the center pouring pipe will increase, and the impact and erosion of the molten steel on the inner basin brick of the center pouring pipe will increase during pouring. If the height of the inner sleeve is too low, it will not be conducive to the formation of a stable flow of argon gas; the conical surface of the inner sleeve is provided with an upper and lower layer of angled air outlet holes. In order to achieve the guiding effect of the air outlet holes, the wall thickness of the inner sleeve is 20m to 60mm. This is because the air outlet holes that meet the direction requirements need to be processed on the inner sleeve. In order to achieve the guiding effect of the air outlet holes, the wall thickness of the inner sleeve should not be too small; but the wall thickness of the inner sleeve should not be too large. If the wall thickness is too large, it will be difficult to roll into a cylinder, and the argon protection ring will be bulky and not conducive to installation.

[0060] Specifically, the inner cross section of the inner sleeve is conical, and the inner diameter of the upper opening is D 上 , the inner diameter of the lower opening is D 下 When the steel ingot is cast using double-layer slide casting, the inner diameter D of the upper opening of the inner sleeve 上 Need to meet: D 上 ≥D 外 And D 上 ≥L+D 水 / 2; where D 外 is the outer diameter of the ladle nozzle refractory, L is the nozzle sliding stroke when using double-layer slide casting, D 水 is the diameter of the ladle nozzle, the unit is mm; when the three-layer slide plate is used for casting the steel ingot, the nozzle sliding stroke L during the three-layer slide plate casting is 0mm. 下 Need to meet: D 下 >D 砖 , where D 砖 D is the outer diameter of the basin brick in the center injection pipe; in order to facilitate the processing of the air hole in the inner sleeve, 下 The value should be as large as possible. Preferably, D 下 Equal to the inner diameter of the outer sleeve.

[0061] Specifically, the air outlet holes opened on the conical surface of the inner sleeve include upper air outlet holes and lower air outlet holes, the opening directions of the upper air outlet holes and the lower air outlet holes are different, the number of the upper air outlet holes and the lower air outlet holes is the same, both are N, and the value range of N is 4 to 16; the upper air outlet holes and the lower air outlet holes are evenly distributed around the circumference of the inner sleeve, the upper and lower layers of air outlet holes are symmetrical, and the angle between each pair of air outlet holes is 360° / N; preferably, the multiple air outlet holes are 8 pairs in total, 16 in total, in the upper and lower layers, evenly distributed around, and the angle between each pair of air outlet holes is 45°; the diameter of the air outlet holes is consistent with the inner diameter of the air inlet pipe, and the position of the air outlet holes is 1 to 5 mm away from the upper and lower end surfaces of the inner sleeve, so as to facilitate the processing and manufacturing of the air outlet holes. Preferably, the position of the air outlet holes is 1 mm away from the upper and lower end surfaces of the inner sleeve. Among them, the top surface of the inner sleeve is a horizontal plane, and the upper air outlet holes maintain an angle α with the horizontal plane, and the size of the angle is determined according to the diameter D of the air outlet holes. 孔 、Inner diameter of inner sleeve upper opening D 上 and the outer diameter D of the ladle nozzle refractory 外 Design; minimum value of α min Satisfaction: sinα min =2×D 孔 / (D 上 -D 外 ); the bottom end surface of the inner sleeve is a horizontal plane, and the lower air outlet maintains an angle β with the horizontal plane, and the size of the angle is based on the diameter D of the air outlet 孔 、Inner diameter of the lower end of the inner sleeve D 下 , the outer diameter D of the basin brick in the middle injection pipe 砖 Design; minimum value of β min Satisfies: sinβ min =2×D 孔 / (D 下 -D 砖 ); The angles α and β respectively determine the direction of the air outlet, ensuring good argon protection effect and positive pressure environment of the gas chamber, while avoiding direct impact on the molten steel stream, reducing the swing of the molten steel stream and the erosion of the molten steel on the refractory, and ensuring that the products produced by the steel ingot are qualified in ultrasonic testing.

[0062] Specifically, the cover plate and the middle plate are made of steel plates with a thickness of 2 to 3 mm, ensuring that the cover plate and the middle plate have sufficient strength for reuse; the cover plate is an annular plate with a hole in the middle, the outer diameter of the cover plate is equal to the outer diameter of the outer sleeve, and the inner diameter of the cover plate is equal to the upper inner diameter of the inner sleeve. The middle plate is an annular plate with a hole in the middle, the outer diameter of the middle plate is equal to the inner diameter of the outer sleeve, and is larger than the lower inner diameter of the inner sleeve, and the inner diameter of the middle plate is 10 to 20 mm larger than the outer diameter of the basin brick in the center injection tube. The dimensions of the cover plate and the middle plate meet the requirements to ensure the sealing of the air chamber, ensure that the middle plate has enough area to fall on the top surface of the center injection tube, and realize the sealing of the air chamber; at the same time, ensure that the basin brick can pass through the inner hole of the middle plate for easy assembly.

[0063] Specifically, four air inlet pipes are arranged outside the outer sleeve, and the two ends of the four air inlet pipes are connected to the main pipe and the outer sleeve by welding. The air inlet pipes surround the outer sleeve and are evenly distributed. The angle between the air inlet pipes is 90°. At the same time, the four air inlet pipes are staggered with the air outlet holes on the inner sleeve. The angle between each air inlet pipe and the adjacent pair of air outlet holes is 360° / 2N, and N is 4 to 16. Meeting this angle condition can prevent the argon gas in the air inlet pipe from directly impacting the air outlet holes, thereby causing the argon gas pressure of individual air outlet holes to be greater than that of other air outlet holes, affecting the uniform distribution of the positive pressure environment in the air chamber. The inner diameter of the air inlet pipe is equal to the inner diameter of the ventilation pipe, which is 20 to 30 mm, and the wall thickness is 1 to 2 mm.

[0064] The present invention also provides a method for preparing an inner conical argon protection ring, which is used to prepare the inner conical argon protection ring, comprising:

[0065] S1: Design the size and shape of the main pipe, outer sleeve, inner sleeve, cover plate, middle plate, air inlet pipe, air outlet hole and vent pipe;

[0066] S2: According to the size and shape of the intake pipe and the vent pipe, the intake pipe and the vent pipe are processed by thin-walled steel pipe;

[0067] S3: According to the size and shape of the outer sleeve and the inner sleeve, the outer sleeve and the inner sleeve are manufactured by rolling the steel plate;

[0068] S4: According to the size and shape of the cover plate and the middle plate, the cover plate and the middle plate are manufactured by processing the steel plate;

[0069] S5: According to the size and shape of the air outlet holes, N pairs of air outlet holes are processed at a distance of 1 to 5 mm from the upper and lower end surfaces of the inner sleeve, and the air outlet holes are kept at an inclined angle to the horizontal plane;

[0070] S6: Weld the vent pipe to the main pipe, weld the two ends of the air inlet pipe to the outside of the main pipe and the outer sleeve respectively, and connect the main pipe and the outer sleeve;

[0071] S7: The top surfaces of the inner sleeve and the outer sleeve are coplanar, and the cover plate is welded to the top surfaces of the outer sleeve and the inner sleeve;

[0072] S8: Weld the middle plate to the bottom end surface of the inner sleeve to form an air chamber, thereby obtaining an inner conical argon protection ring.

[0073] Specifically, the sizes and shapes of the main pipe, outer sleeve, inner sleeve, cover plate, middle plate, air inlet pipe, air outlet hole, and vent pipe, and the inclination angles of the horizontal planes of the upper and lower ends of the air outlet hole and the inner sleeve need to meet the requirements as described above.

[0074] The argon protection ring prepared by the present invention is used in the atmospheric pouring steel ingot casting process, which comprises the following steps:

[0075] S1: During pouring, the inner conical argon protection ring is nested on the middle pouring tube, and asbestos rings are provided on the top surfaces of the middle pouring tube and the argon protection ring;

[0076] S2: Argon enters the main pipe through the vent pipe of the conical argon protection ring, then enters the air chamber through the air inlet pipe, and then enters the surrounding of the molten steel stream through the air outlet hole on the inner sleeve.

[0077] It should be noted that the ladle seat is on the casting car, the ladle water inlet is aligned with the center of the center pouring pipe during pouring, the bottom of the ladle and the top surface of the argon protection ring are compacted and sealed; the asbestos ring avoids the rigid contact between the top surface of the center pouring pipe and the middle plate to produce a gap, which is more conducive to the formation of argon protection atmosphere and prevents air from entering.

[0078] Example 1

[0079] The present embodiment relates to the design and use of an inner conical argon protection ring for 61-104 ton atmospheric casting steel ingots.

[0080] The schematic diagram of the inner cone argon protection ring is shown in the attached figure. Figure 1 to Figure 3 .

[0081] In this embodiment, the outer diameter of the injection pipe used is D 中注管 500mm; the outer diameter of the basin brick used is D 砖 320mm; outer diameter of ladle nozzle refractory material D 外 170mm; ladle nozzle diameter D 水 The sliding stroke of the gate for double-layer sliding plate casting is L, which is 150mm.

[0082] In this embodiment, the size and shape of the inner conical argon protection ring are designed as follows:

[0083] S1: Design the size and shape of the main pipe, outer sleeve, inner sleeve, cover plate, middle plate, air inlet pipe, air outlet hole and vent pipe;

[0084] S2: According to the size and shape of the intake pipe and the vent pipe, the intake pipe and the vent pipe are processed by thin-walled steel pipe;

[0085] The outer diameter of the vent pipe and the intake pipe is 32mm, the inner diameter is 30mm, and the wall thickness is 1mm.

[0086] S3: According to the size and shape of the outer sleeve and the inner sleeve, the outer sleeve and the inner sleeve are manufactured by rolling the steel plate;

[0087] Among them, the outer sleeve height H 外 The inner sleeve is 450mm (1.96 times the height of the inner sleeve), the inner diameter of the outer sleeve is 520mm (20mm larger than the outer diameter of the middle injection pipe of 500mm), the wall thickness is 3mm, and the outer diameter of the outer sleeve is 526mm; the inner sleeve height H 内230mm, wall thickness 20mm, inner diameter of inner sleeve top D 上 330mm, inner diameter of the inner sleeve bottom D 下 420mm; the inner diameter of the outer sleeve is 10 to 25mm larger than the outer diameter of the middle injection pipe, and the height of the outer sleeve is designed to be 1.5 to 2.0 times the height of the inner sleeve.

[0088] S4: According to the size and shape of the cover plate and the middle plate, the cover plate and the middle plate are manufactured by processing the steel plate;

[0089] The outer diameter of the cover plate is 523mm, the inner diameter is 330mm, and the wall thickness is 3mm; the outer diameter of the middle plate is 520mm, the inner diameter is 340mm, and the wall thickness is 3mm. The outer diameter of the cover plate is equal to the outer diameter of the outer sleeve, the inner diameter of the cover plate is equal to the inner diameter of the upper opening of the inner sleeve; the outer diameter of the middle plate is equal to the inner diameter of the outer sleeve, and the inner diameter of the middle plate is 10 to 20mm larger than the outer diameter of the basin brick in the middle injection pipe.

[0090] S5: According to the size and shape of the air outlet holes, 8 air outlet holes are processed at 3mm from the upper and lower end surfaces of the inner sleeve, a total of 8 pairs of 16 holes, evenly distributed around the inner sleeve, the angle between each pair of air outlet holes is 45°, and the opening diameter of the air outlet hole is D 孔 =30mm; the upper air outlet maintains an angle of α with the horizontal plane, α = 30°, and the lower air outlet maintains an angle of β with the horizontal plane, β = 80°. Satisfy α>α min , β>β min Among them, sinα min =2×D 孔 / (D 上 -D 外 )=0.375,α min＝ 22°; sinβ min =2×D 孔 / (D 下 -D 砖 )=0.6,β min =36.87°.

[0091] S6: Weld the vent pipe to the main pipe, weld the two ends of the intake pipe to the outside of the main pipe and the outer sleeve respectively, and connect the main pipe and the outer sleeve; wherein the intake pipe surrounds the outer sleeve and is evenly distributed, and the angle between the intake pipes is 90°, wherein the intake pipe and the air outlet holes on the inner sleeve are staggered, and the angle between each intake pipe and the adjacent pair of air outlet holes is 22.5° (i.e., 360° / 2N=360° / 16=22.5°);

[0092] S7: The top surfaces of the inner sleeve and the outer sleeve are coplanar, and the cover plate is welded to the top surfaces of the outer sleeve and the inner sleeve;

[0093] S8: Weld the middle plate to the bottom end surface of the inner sleeve to form an air chamber, thereby obtaining an inner conical argon protection ring.

[0094] During pouring, the inner conical argon protection ring is nested on the middle pouring pipe, and asbestos rings are provided on the top surfaces of the middle pouring pipe and the argon protection ring; the argon enters the main pipe through the vent pipe of the conical argon protection ring, then enters the air chamber through the air inlet pipe, and then enters around the molten steel flow through the air outlet hole on the inner sleeve.

[0095] During the refining and steel tapping, the gas content of molten steel was measured as H: 0.8ppm, O: 21ppm, N: 45ppm; after the pouring, Tangdao Steel took samples and measured the gas content of steel as H: 1.1ppm, O: 24ppm, N: 49ppm; the gas content of the final steel ingot product was H: 0.9ppm, O: 19ppm, N: 44ppm. Compared with the gas content in the steel ingot during steel tapping, the gas content of the final steel ingot product increased by 0.1ppm in H, decreased by 2ppm in O, and decreased by 1ppm in N. It can be seen that in this embodiment, the gas in the steel is controlled, effectively ensuring the product quality; at the same time, the product produced by the steel ingot passed the ultrasonic test.

[0096] Example 2

[0097] The present embodiment relates to the design and use of an inner conical argon protection ring for 80-130 ton atmospheric casting steel ingots.

[0098] The schematic diagram of the inner cone argon protection ring is shown in the attached figure. Figure 1 to Figure 3 .

[0099] In this embodiment, the outer diameter of the injection pipe used is D 中注管 726mm; the outer diameter of the basin brick used is D 砖 370mm; outer diameter of ladle nozzle refractory material D 外 170mm; ladle nozzle diameter D 水 The sliding stroke of the gate for double-layer sliding plate casting is L, which is 150mm.

[0100] In this embodiment, the size and shape of the inner conical argon protection ring are designed as follows:

[0101] S1: Design the size and shape of the main pipe, outer sleeve, inner sleeve, cover plate, middle plate, air inlet pipe, air outlet hole and vent pipe;

[0102] S2: According to the size and shape of the intake pipe and the vent pipe, the intake pipe and the vent pipe are processed by thin-walled steel pipe;

[0103] The outer diameter of the vent pipe and the intake pipe is 32mm, the inner diameter is 30mm, and the wall thickness is 1mm;

[0104] S3: According to the size and shape of the outer sleeve and the inner sleeve, the outer sleeve and the inner sleeve are manufactured by rolling the steel plate;

[0105] Among them, the outer sleeve height H 外 550mm (1.83 times the height of the inner sleeve), the inner diameter of the outer sleeve is 746mm (20mm larger than the outer diameter of the middle injection tube 726mm), the wall thickness is 3mm, and the outer diameter of the outer sleeve is 752mm; the height of the inner sleeve is H 内 300mm, wall thickness 30mm, inner diameter of inner sleeve top D 上 330mm, inner diameter of the inner sleeve bottom D 下 622mm; the inner diameter of the outer sleeve is 10 to 25mm larger than the outer diameter of the middle injection pipe; the height of the outer sleeve is designed to be 1.5 to 2.0 times the height of the inner sleeve.

[0106] S4: According to the size and shape of the cover plate and the middle plate, the cover plate and the middle plate are manufactured by processing the steel plate;

[0107] The outer diameter of the cover plate is 752mm, the inner diameter is 330mm, and the wall thickness is 3mm; the outer diameter of the middle plate is 746mm, the inner diameter is 390mm, and the wall thickness is 3mm. The outer diameter of the cover plate is equal to the outer diameter of the outer sleeve, the inner diameter of the cover plate is equal to the inner diameter of the upper opening of the inner sleeve; the outer diameter of the middle plate is equal to the inner diameter of the outer sleeve, and the inner diameter of the middle plate is 10 to 20mm larger than the outer diameter of the basin brick in the middle injection pipe.

[0108] S5: According to the size and shape of the air outlet holes, 8 air outlet holes are processed at 5mm from the upper and lower end surfaces of the inner sleeve, a total of 8 pairs of 16 holes, evenly distributed around the inner sleeve, the angle between each pair of air outlet holes is 45°, and the opening diameter of the air outlet hole is D 孔 =30mm; the upper air outlet maintains an angle of α with the horizontal plane, α = 23°, and the lower air outlet maintains an angle of β with the horizontal plane, β = 36°. Satisfy α>α min , β>β min Among them, sinα min =2×D 孔 / (D 上 -D 外 )=0.375,α min＝ 22°; sinβ min =2×D 孔 / (D 下 -D 砖 )=0.238,β min =15.3°.

[0109] S6: Weld the vent pipe to the main pipe, weld the two ends of the intake pipe to the outside of the main pipe and the outer sleeve respectively, and connect the main pipe and the outer sleeve; wherein the intake pipe surrounds the outer sleeve and is evenly distributed, and the angle between the intake pipes is 90°, wherein the intake pipe and the air outlet holes on the inner sleeve are staggered, and the angle between each intake pipe and the adjacent pair of air outlet holes is 22.5° (i.e., 360° / 2N=360° / 16=22.5°);

[0110] S7: The top surfaces of the inner sleeve and the outer sleeve are coplanar, and the cover plate is welded to the top surfaces of the outer sleeve and the inner sleeve;

[0111] S8: Weld the middle plate to the bottom end surface of the inner sleeve to form an air chamber, thereby obtaining an inner conical argon protection ring.

[0112] During pouring, the inner conical argon protection ring is nested on the middle pouring pipe, and asbestos rings are provided on the top surfaces of the middle pouring pipe and the argon protection ring; the argon enters the main pipe through the vent pipe of the conical argon protection ring, then enters the air chamber through the air inlet pipe, and then enters around the molten steel flow through the air outlet hole on the inner sleeve.

[0113] During refining and steelmaking, the gas contents in the molten steel were measured as H: 0.9ppm, O: 25ppm, and N: 63ppm; after pouring, Tangdao Steel took samples and measured the gas contents in the steel as H: 1.0ppm, O: 22ppm, and N: 57ppm; the gas contents of the finally prepared steel ingot product were H: 1.1ppm, O: 23ppm, and N: 62ppm. Compared with the gas content in the steel ingot during steelmaking, the gas content of the finally prepared steel ingot product increased by 0.2ppm in H, decreased by 2ppm in O, and decreased by 1ppm in N. It can be seen that in this embodiment, the gas in the steel is controlled, which effectively guarantees the product quality; the products produced by the steel ingot are qualified in ultrasonic testing.

[0114] Comparative Example 1

[0115] This comparative example involves 61-104 ton atmospheric casting steel ingots (same as Example 1), and the use of an existing common argon protection ring.

[0116] The inner and outer sleeves of the existing common argon protection ring are both cylindrical. Figure 4 .

[0117] In this comparative example, the outer diameter of the injection pipe used is D 中注管 500mm; the outer diameter of the basin brick used is D 砖 320mm; outer diameter of ladle nozzle refractory material D 外 170mm; ladle nozzle diameter D 水 The sliding stroke of the gate for double-layer sliding plate casting is L, which is 150mm.

[0118] In this comparative example, the size and shape of the ordinary argon protection ring are as follows: the outer sleeve and inner sleeve of the argon protection ring are both cylindrical, the outer sleeve has an inner diameter of 520mm, a wall thickness of 3mm, and an outer sleeve outer diameter of 526mm; the inner sleeve has an inner diameter of 350mm, a wall thickness of 20mm, and an outer sleeve outer diameter of 390mm.

[0119] During pouring, a common argon protection ring is nested on the middle pouring tube; the argon enters the air chamber through the air inlet pipe, and then enters around the molten steel stream through the air outlet holes on the inner sleeve.

[0120] During refining and steelmaking, the gas contents in the molten steel were measured as H: 1.0ppm, O: 25ppm, and N: 68ppm; after pouring, Tangdao Steel was sampled and the gas contents in the steel were measured as H: 1.5ppm, O: 29ppm, and N: 69ppm; the gas contents of the finally prepared steel ingot product were H: 1.8ppm, O: 28ppm, and N: 76ppm. Compared with the gas content in the steel ingot during steelmaking, the gas content of the finally prepared steel ingot product increased by 0.8ppm, the O content increased by 3ppm, and the N content decreased by 8ppm. The fluctuation value of the H content in this comparative example is much greater than that in Examples 1 and 2. It can be seen that in this comparative example, the gas content in the steel is not effectively controlled.

[0121] Comparative Example 2

[0122] The present embodiment relates to the design and use of an inner conical argon protection ring for 61-104 ton atmospheric casting steel ingots.

[0123] The schematic diagram of the inner cone argon protection ring is shown in the attached figure. Figure 1 to Figure 3 .

[0124] In this embodiment, the outer diameter of the injection pipe used is D 中注管 500mm; the outer diameter of the basin brick used is D 砖 320mm; outer diameter of ladle nozzle refractory material D 外 170mm; ladle nozzle diameter D 水 The sliding stroke of the gate for double-layer sliding plate casting is L, which is 150mm.

[0125] In this embodiment, the size and shape of the inner conical argon protection ring are designed as follows:

[0126] S1: Design the size and shape of the main pipe, outer sleeve, inner sleeve, cover plate, middle plate, air inlet pipe, air outlet hole and vent pipe;

[0127] S2: According to the size and shape of the intake pipe and the vent pipe, the intake pipe and the vent pipe are processed by thin-walled steel pipe;

[0128] The outer diameter of the vent pipe and the intake pipe is 32mm, the inner diameter is 30mm, and the wall thickness is 1mm.

[0129] S3: According to the size and shape of the outer sleeve and the inner sleeve, the outer sleeve and the inner sleeve are manufactured by rolling the steel plate;

[0130] Among them, the outer sleeve height H 外322mm (1.4 times the height of the inner sleeve), the inner diameter of the outer sleeve is 520mm, the wall thickness is 3mm, and the outer diameter of the outer sleeve is 526mm; the inner sleeve height H 内 230mm, wall thickness 20mm, inner diameter of inner sleeve top D 上 330mm, inner diameter of the inner sleeve bottom D 下 420mm; the inner diameter of the outer sleeve is 10 to 25mm larger than the outer diameter of the middle injection pipe; the requirement that the height of the outer sleeve is designed to be 1.5 to 2.0 times the height of the inner sleeve is not met.

[0131] S4: According to the size and shape of the cover plate and the middle plate, the cover plate and the middle plate are manufactured by processing the steel plate;

[0132] The outer diameter of the cover plate is 523mm, the inner diameter is 330mm, and the wall thickness is 3mm; the outer diameter of the middle plate is 520mm, the inner diameter is 340mm, and the wall thickness is 3mm. The outer diameter of the cover plate is equal to the outer diameter of the outer sleeve, the inner diameter of the cover plate is equal to the inner diameter of the upper opening of the inner sleeve; the outer diameter of the middle plate is equal to the inner diameter of the outer sleeve, and the inner diameter of the middle plate is 10 to 20mm larger than the outer diameter of the basin brick in the middle injection pipe.

[0133] S5: According to the size and shape of the air outlet holes, 8 air outlet holes are processed at 3mm from the upper and lower end surfaces of the inner sleeve, a total of 8 pairs of 16 holes, evenly distributed around the inner sleeve, the angle between each pair of air outlet holes is 45°, and the opening diameter of the air outlet hole is D 孔 =30mm; the upper air outlet maintains an angle of α with the horizontal plane, α=5°, β=10°; Not satisfied: α>α min , β>β min ; Among them, sinα min =2×D 孔 / (D 上 -D 外 )=0.375,α min＝ 22°; sinβ min =2×D 孔 / (D 下 -D 砖 )=0.6,β min =36.87°.

[0134] S6: Weld the vent pipe to the main pipe, weld the two ends of the intake pipe to the outside of the main pipe and the outer sleeve respectively, and connect the main pipe and the outer sleeve; wherein the intake pipe surrounds the outer sleeve and is evenly distributed, and the angle between the intake pipes is 90°, wherein the intake pipe and the air outlet holes on the inner sleeve are staggered, and the angle between each intake pipe and the adjacent pair of air outlet holes is 22.5° (i.e., 360° / 2N=360° / 16=22.5°);

[0135] S7: The top surfaces of the inner sleeve and the outer sleeve are coplanar, and the cover plate is welded to the top surfaces of the outer sleeve and the inner sleeve;

[0136] S8: Weld the middle plate to the bottom end surface of the inner sleeve to form an air chamber, thereby obtaining an inner conical argon protection ring.

[0137] During pouring, the inner conical argon protection ring is nested on the middle pouring pipe, and asbestos rings are provided on the top surfaces of the middle pouring pipe and the argon protection ring; the argon enters the main pipe through the vent pipe of the conical argon protection ring, then enters the air chamber through the air inlet pipe, and then enters around the molten steel flow through the air outlet hole on the inner sleeve.

[0138] During refining and steelmaking, the gas contents in the molten steel were measured as H: 1.0ppm, O: 22ppm, and N: 41ppm; after pouring, Tangdao Steel was sampled and the gas contents in the steel were measured as H: 1.3ppm, O: 24ppm, and N: 65ppm; the gas contents of the finally prepared steel ingot product were H: 1.4ppm, O: 23ppm, and N: 65ppm. Compared with the gas content in the steel ingot during steelmaking, the gas content of the finally prepared steel ingot product increased by 0.4ppm in H, 1ppm in O, and 24ppm in N. The fluctuation value of the H content in this comparative example is much greater than that in Examples 1 and 2. It can be seen that in this comparative example, the gas content in the steel is not effectively controlled.

[0139] It can be seen from Examples 1 and 2 and Comparative Example 1 that the inner conical inner sleeve reduces the size of the argon outlet, which significantly promotes the guarantee of an argon positive pressure environment around the molten steel stream, effectively prevents external air from entering around the molten steel stream, and better controls the molten steel suction effect.

[0140] It can be seen from Examples 1, 2 and Comparative Example 2 that the inner conical argon protection ring used in Comparative Example 2 has a weakened sealing environment for argon because the outlet hole does not point to the argon outlet. In addition, the argon impacts the molten steel stream, causing the molten steel stream to swing, increasing the erosion of the molten steel on the refractory, and increasing the number of foreign inclusions in the steel ingot, resulting in ultrasonic flaw detection problems.

[0141] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. An inner conical argon protection ring, characterized in that: The inner conical argon protection ring comprises an inner sleeve, an outer sleeve and a main pipe which are sequentially sleeved from the inside to the outside; The main pipe is a hollow annular pipe, which is connected to the outer sleeve through the air inlet pipe; The inner sleeve is a conical hollow sleeve, which is connected to the outer sleeve through an air outlet hole provided on the conical surface; The top ends of the inner sleeve and the outer sleeve are connected through a cover plate, the bottom end of the inner sleeve is connected to the inner wall side of the outer sleeve through a middle plate, and the outer wall of the inner sleeve, the inner wall of the outer sleeve, the lower end face of the cover plate and the upper end face of the middle plate together form an air chamber.

2. The inner conical argon protection ring according to claim 1 is characterized in that: The air outlet holes formed on the conical surface of the inner sleeve include upper air outlet holes and lower air outlet holes, and the upper air outlet holes and the lower air outlet holes have different opening directions.

3. The inner conical argon protection ring according to claim 2, characterized in that: The number of the upper layer air outlet holes and the number of the lower layer air outlet holes are the same, both N, and the value range of N is 4 to 16; The upper air outlet holes and the lower air outlet holes are evenly distributed around the circumference of the inner sleeve.

4. The inner conical argon protection ring according to claim 2, characterized in that: The upper air outlet holes are 1 to 5 mm away from the top end surface of the inner sleeve, and the lower air outlet holes are 1 to 5 mm away from the bottom end surface of the inner sleeve.

5. The inner conical argon protection ring according to claim 2, characterized in that: The top surface of the inner sleeve is a horizontal plane, and the upper air outlet hole maintains an angle α with the top surface of the inner sleeve, and the minimum value of α is min Satisfaction: sinα min =2×D 孔 / (D 上 -D 外 ); Wherein, α is the angle between the upper air outlet and the horizontal plane of the top surface of the inner sleeve, °; D 孔 is the diameter of the air outlet, mm; D 上 is the inner diameter of the upper opening of the inner sleeve, mm; D 外 is the outer diameter of the ladle nozzle refractory, mm.

6. The inner conical argon protection ring according to claim 2, characterized in that: The bottom end surface of the inner sleeve is a horizontal plane, and the lower layer air outlet hole maintains an angle β with the horizontal plane of the bottom end surface of the inner sleeve, and the minimum value β min Satisfies: sinβ min =2×D 孔 / (D 下 -D 砖 ); Wherein, β is the angle between the lower air outlet and the horizontal plane of the bottom end surface of the inner sleeve, °; D 孔 is the diameter of the air outlet, mm; D 下 is the inner diameter of the lower opening of the inner sleeve, mm; D 砖 is the outer diameter of the basin brick inside the center injection pipe, mm.

7. The inner conical argon protection ring according to claim 1, characterized in that: The cover plate is an annular plate with a hole in the middle, and the outer diameter of the cover plate is equal to the outer diameter of the outer sleeve.

8. The inner conical argon protection ring according to claim 1, characterized in that: The height of the outer sleeve is 1.5 to 2.0 times the height of the inner sleeve.

9. The inner conical argon protection ring according to claim 1, characterized in that: When the steel ingot is cast using double-layer slide casting, the inner sleeve meets the following requirements: 上 ≥D 外 And D 上 ≥L+D 水 / 2; Among them, D 上 is the inner diameter of the upper opening of the inner sleeve, mm; D 外 is the outer diameter of the ladle nozzle refractory, mm; L is the sliding stroke of the nozzle when casting with double-layer slide plates, mm; D 水 is the diameter of the ladle nozzle, mm; When the ingot is cast using three-layer slide casting, the inner sleeve meets the following requirements: 下 >D 砖 ; Among them, D 下 is the inner diameter of the lower opening of the inner sleeve, mm; D 砖 is the outer diameter of the basin brick inside the center injection pipe, mm.

10. A method for preparing an inner conical argon protection ring, characterized in that: Used to prepare the inner conical argon protection ring according to any one of claims 1 to 9.

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