A device and method for protecting a crystallizer from splashing and oxidation of molten steel by adding rare earth wire

Abstract

The application discloses a device and method for protecting a crystallizer by adding rare earth filaments and preventing splashing and oxidation of molten steel, wherein a rare earth feeder is arranged in a penetrating structure with the upper end arranged in air and the lower end extending into the molten steel, the first argon hole opening position of the feeder exposed below the protective slag is 30-50 mm higher than the crystallizer, the interval of each hole is 40-70 mm, the diameter is 2.5-8 mm, the angle between the argon hole and the horizontal direction is 30-60 degrees, the total flow of argon is 3-4 atmospheres, and a directional and stable inert gas protection barrier is formed. The application can effectively isolate the contact between air and the molten steel liquid surface in the crystallizer, inhibit the secondary oxidation of the molten steel, improve the dissolution uniformity of the rare earth filaments, reduce defects such as oxidation inclusions of the cast slab, significantly improve the comprehensive quality of the steel, and is suitable for large-scale continuous casting production application.

Description

Technical Field

[0001] This invention belongs to the field of steelmaking technology in the metallurgical industry, specifically relating to a device and method for protective addition of rare earth wires to a crystallizer to prevent splashing and oxidation of molten steel. Background Technology

[0002] Rare earth elements can significantly improve the toughness, plasticity, wear resistance, and corrosion resistance of steel, enabling microalloyed steel to achieve superior overall performance. In my country, rare earth steel is mainly used in low-carbon steel and Nb, V, and Ti microalloyed steel.

[0003] Currently, the technology and equipment for adding rare earth elements are not yet mature, leading to a series of problems in the development and production of rare earth steel.

[0004] Existing literature 1: Chen Benwen et al. from the State Key Laboratory of Marine Equipment Metallic Materials and Their Applications introduced (The Influence of Rare Earth Feeding in the Slab Mold on Inclusions and Low-Temperature Toughness of 30CrMnMo Steel). Given the purifying, inclusion-modifying, and microalloying effects of rare earth elements in steel, this experiment involved feeding rare earth wires into the mold during the continuous casting of medium-carbon, low-alloy 30CrMnMo steel to achieve good mechanical properties in the final product. However, rare earth elements easily come into contact with the protective slag and react to form large-particle inclusions, which is detrimental to the control of steel purity.

[0005] Existing literature 2: Zhao Chenglin of the Iron and Steel Research Institute of Ansteel Group published "Research on the Mechanism of Action and Addition Technology of Rare Earth Elements in Molten Steel" in Ansteel Technology, which introduces that the most mature rare earth addition process currently used is the continuous casting mold wire feeding method. This process feeds rare earth wire into the molten steel in the mold during continuous casting, avoiding turbulence at the nozzle. Because the time interval between the addition of rare earth elements and solidification is very short, they do not have enough time to diffuse fully, reducing the chance of oxidation. At the same time, rare earth elements have minimal contact with refractory materials, thus greatly improving the utilization rate of rare earths. Currently, the rare earth element recovery rate of the mold wire feeding process can reach over 90%. However, rare earths easily come into contact with the protective slag and react to form large particle inclusions, which is detrimental to the control of molten steel purity.

[0006] Existing literature 3: Liu Zhilong of Baosteel Group Guangdong Shaoguan Iron & Steel Co., Ltd. (Research and Control of Castability of Cold Heading Steel SWRCH6A) introduces that when Shaoguan Steel Plant produces cold heading steel SWRCH6A, the nozzle is prone to blockage during continuous casting. After the nozzle is blocked, the liquid level in the continuous casting crystallizer fluctuates greatly, and the molten steel in the crystallizer is prone to slag entrainment and secondary oxidation. In severe cases, the continuous casting machine may even stop abnormally. However, this article does not propose measures to prevent oxidation of molten steel using argon gas. Summary of the Invention

[0007] The purpose of this invention is to provide a device and method for protective addition of rare earth wires to a crystallizer and to prevent splashing and oxidation of molten steel, so as to solve the problems mentioned in the background art.

[0008] The objective of this invention is achieved through the following technical solution: a device for protective addition of rare earth wire to a crystallizer and for preventing splashing and oxidation of molten steel, comprising a wire feeding platform, on which a wire feeder is provided, the vertical direction of which is connected to the wire feeding platform in a vertical through-type structure, the upper end of which extends into the air, and the lower end of which extends into the molten steel inside the crystallizer.

[0009] The lower part of the wire feeder exposed to the protective slag is provided with an argon gas passage, and the upper end of the wire feeder is provided with an argon gas port, which is connected to an argon gas blowing pipe with a diameter of 4-7 mm. The outer diameter of the wire feeder is 15-50 mm.

[0010] Furthermore, the height of the wire feeder in the vertical direction is 200-750mm; the cross-sectional shape of the wire feeder is an inverted "7" shape.

[0011] Furthermore, a peripheral cavity is provided on the vertical periphery of the wire feeder and fixedly connected to the wire feeder. The wire feeder and the peripheral cavity form an annular cavity. A wire feeding channel is provided in the center of the wire feeder, and rare earth wire is provided in the wire feeding channel. The wire feeder is a high-temperature resistant and oxidation-resistant rare earth wire feeder. The high-temperature resistant conduit is made of zirconium oxide material or other materials with a melting point ≥1600℃. The conduit is embedded with alloy tubes of the same or different materials with a melting point ≥1600℃.

[0012] Furthermore, the wire feeder has argon gas holes spaced apart in the vertical direction, and the wire feeding channel at the junction of the vertical and inclined directions of the wire feeder has a rounded corner structure.

[0013] Furthermore, the wire feeding platform is a height-adjustable wire feeding platform, and the wire feeding platform is set within a range of 5-20mm from the outer surface of the sprue;

[0014] A positioning frame is fixedly installed on the outer cavity of the wire feeder and is fixedly connected to the wire feeder. The positioning frame is connected to the wire feeding platform.

[0015] Furthermore, the angle between the tilting direction of the wire feeder and the horizontal line is in the range of 10-60°, wherein the length of the tilting direction of the wire feeder is 2000-5000mm.

[0016] Furthermore, the argon gas passages are spaced along the wire feeder, with the opening position of the first argon gas passage having a height difference of 30-50mm from the top of the crystallizer, and the center-to-center distance between two adjacent argon gas passages being 40-70mm.

[0017] Furthermore, the diameter of each argon gas passage is 2.5-8mm, and the angle between each argon gas passage and the horizontal direction is 30°-60°.

[0018] Furthermore, the argon gas outlets are evenly distributed along the circumference of the wire feeder, with the argon gas output direction facing the molten steel surface of the crystallizer.

[0019] A method for applying a crystallizer protective device for incorporating rare earth wires and preventing splashing and oxidation of molten steel includes the following steps:

[0020] S1. During continuous casting production, the vertical part of the wire feeder is installed on the wire feeding platform. The wire feeding platform is adjusted to make the lower end of the wire feeder reach the inside of the crystallizer, ensuring that the upper end of the rare earth wire feeder is in the air and the lower end is immersed in the molten steel, and ensuring that the height difference between the first argon gas hole and the top of the crystallizer is 30-50mm.

[0021] S2. The argon port at the top of the wire feeder is connected to the argon blowpipe, which is connected to the argon supply equipment. The argon supply equipment is started to introduce argon into the argon delivery channel of the wire feeder. The total flow rate and pressure of argon are controlled to be 3-4 atmospheres. Argon is injected directionally through 3-4 argon holes to form an annular inert gas protection zone above the protective slag and around the wire feeder.

[0022] Argon gas enters the annular sealed cavity of the wire feeder from the argon port at the top of the wire feeder. The argon gas inside the cavity is arranged downwards at 30°-60° with three inclined openings with a diameter of Φ2.5-8mm and the axis of the openings facing the horizontal, towards the outer wall of the rare earth wire descending towards the center, forming a protective argon gas layer around the rare earth wire.

[0023] Among them, the ejected argon gas flows downward along the annular gap between the rare earth wire and the inner hole of the wire feeder, and is discharged from the bottom outlet of the wire feeder. It enters the internal space of the crystallizer below. In the area above the surface of the molten steel in the crystallizer, a portion of the argon gas surrounds the rare earth wire that is about to melt into the molten steel to isolate it from the air. A small amount of argon gas immerses into the surface of the molten steel in the crystallizer along with the rare earth wire.

[0024] S3. Maintain a continuous argon injection state and feed rare earth wire into the molten steel in the crystallizer at a uniform speed through the wire feeder. The rare earth wire dissolves uniformly in the molten steel, and performs alloying and inclusion modification treatment on the molten steel.

[0025] S4. Throughout the wire feeding and continuous casting process, maintain an argon supply pressure of 3-4 atmospheres to continuously isolate the external air from the molten steel surface in the crystallizer, inhibiting air oxidation of the molten steel until the single batch wire feeding and billet casting process is completed.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] This invention significantly improves the purity of molten steel by isolating the molten steel surface in the crystallizer from air, thereby inhibiting secondary oxidation of the molten steel from the air at the source.

[0028] This invention avoids the problem of steel leakage caused by the denaturation of the protective slag due to the reaction between the protective slag and rare earth wire, and can also cover the air around the wire feeding area in all directions, significantly improving the rare earth element recovery rate and reducing production costs.

[0029] In this invention, the first argon gas vent hole of the wire feeder, located below the protective slag, is positioned 30-50 mm higher than the crystallizer. The spacing between each vent hole is 40-70 mm, resulting in a total of three argon gas vents with a diameter of 2.5-8 mm. The angle between the argon gas vent holes and the horizontal direction is 30-60 degrees, and the total argon gas flow rate is 3-4 atmospheres, forming a directional and stable inert gas protective barrier. This invention effectively isolates air from contact with the molten steel surface inside the crystallizer, inhibits secondary oxidation of the molten steel, improves the uniformity and yield of rare earth wire dissolution, reduces defects such as oxide inclusions and porosity in the cast billet, and significantly improves the overall quality of the steel, making it suitable for large-scale continuous casting production. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the cooperation between the wire feeder and the crystallizer of the present invention;

[0031] Figure 2 This is an enlarged schematic diagram of the wire feeder of the present invention. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0033] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0034] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Specific Implementation Example 1:

[0036] like Figure 1-2 As shown, a device for protective addition of rare earth wire to a crystallizer and for preventing splashing and oxidation of molten steel includes a wire feeding platform 1, on which a wire feeder 2 is provided. The wire feeder 2 has a vertical through-type structure, with its upper end extending into the air and its lower end extending into the molten steel inside the crystallizer 3.

[0037] The lower part of the wire feeder 2 exposed to the protective slag is provided with an argon gas passage 4, and the upper end of the wire feeder 2 is provided with an argon gas port 5, which is connected to an argon gas blowing pipe with a diameter of 2.5-8mm. The outer diameter of the wire feeder 2 is 20-60mm, and the length of the wire feeder is 100-800mm.

[0038] The feeder 2 has an outer cavity fixedly connected to it, forming an annular cavity 8. A feeding channel 6 is located at the center of the feeder 2, and rare earth wires 7 are placed within the feeding channel. The diameter of the rare earth wires 7 is smaller than the diameter of the feeding channel 6. The feeder 2 is a high-temperature resistant and oxidation-resistant rare earth feeder. It is made of zirconium oxide or other materials with a melting point ≥1600℃ to create a high-temperature resistant conduit. The conduit contains alloy tubes of the same or different materials with a melting point ≥1600℃. The rare earth wires continuously pass through the tubes, causing friction and preventing wear and slag formation on the tube walls, thus improving wear resistance.

[0039] The upper edge of the wire feeder 2 is located within 50-300mm outside the protective slag, and the lower edge is located inside the molten steel.

[0040] The wire feeding platform 1 is a height-adjustable wire feeding platform. The height-adjustable wire feeding platform adopts the vertical sleeve telescopic structure disclosed in the prior art. The wire feeding platform 1 is set within a range of 5-20mm from the outer surface of the sprue.

[0041] The wire feeding platform 1 is fixed on the fixed platform of the crystallizer 3. A positioning frame 9 is fixedly installed on the outer cavity of the wire feeder 2 and is fixedly connected to the wire feeder 2. The positioning frame 9 is bolted to the wire feeding platform 1. The wire feeder 2 and the wire feeding platform 1 are connected by welding or by a detachable method. The detachable method is a bolted connection, and the positioning frame 9 is bolted to the wire feeding platform 1 at the connection point.

[0042] The wire feeding platform 1 is a frame structure. The wire feeding platform 1 includes a horizontal section and a vertical section fixedly connected to the horizontal section. The vertical section is a height-adjustable part. The height of the vertical section is adjusted by bolts using an inner and outer sleeve (with positioning holes evenly distributed on the inner and outer sleeves) disclosed in the prior art. A through hole for accommodating the wire feeder 2 is fixedly opened on the horizontal section of the wire feeding platform 1.

[0043] Among them, the bottom connecting bases of the symmetrical vertical sections on both sides of the wire feeding table 1 are connected to the fixed platform by bolts or welding.

[0044] The argon gas vents 4 are spaced along the wire feeder 2. The height difference between the opening position of the first argon gas vent 4 and the top of the crystallizer 3 is 30-50mm, and the center distance between two adjacent argon gas vents 4 is 40-70mm.

[0045] The diameter of each argon gas passage 4 is 4.5 mm, and the angle between each argon gas passage 4 and the horizontal direction is 30°-60°.

[0046] The argon gas outlet 4 is evenly distributed along the circumference of the wire feeder, and the argon gas output direction is towards the molten steel surface of the crystallizer 3.

[0047] In the above embodiments, the rare earth content in the rare earth-feeding wire is 100%, and the density of the rare earth alloy is 7 g / cm³. 3 The calculated cross-section of the cast billet is 280mm*380mm, and the rare earth wire specification is Φ2.5mm. The rare earth content in the steel is controlled by adjusting the feeding speed of the rare earth wire.

[0048] (1) The angle (α) between the inclination direction of the wire feeder and the horizontal line is 15°. The rare earth wire is fed at 2.5 times the pulling speed to prevent splashing. The inclined section of the wire feeder is a 3m heat-resistant tube.

[0049] 0.25*3.14*2.5*2.5*2.5 / (280*380)*100, then:

[0050] The rare earth content in the steel is 0.012%.

[0051] Alternatively, the rare earth content in the wire feed may be 100%, and the density of the rare earth alloy may be 7 g / cm³. 3The calculated cross-section of the cast billet is 280mm*380mm, and the rare earth wire specification is Φ2.5mm. The rare earth content in the steel is controlled by adjusting the feeding speed of the rare earth wire.

[0052] (2) The angle (α) between the inclination direction of the wire feeder and the horizontal line is 25°.

[0053] Rare earth wires are fed at 5 times the pulling speed to prevent splashing. The inclined section of the wire feeder has a 3m heat-resistant tube.

[0054] 0.25*3.14*2.5*2.5*5 / (280*380)*100, then:

[0055] The rare earth content in the steel is 0.023%. Specific Implementation Example 2:

[0057] A method for applying a crystallizer protective device for incorporating rare earth wires and preventing splashing and oxidation of molten steel includes the following steps:

[0058] S1. During continuous casting production, the vertical part of the wire feeder is installed on the wire feeding platform. The wire feeding platform is adjusted to make the lower end of the wire feeder reach the inside of the crystallizer, ensuring that the upper end of the rare earth wire feeder is in the air and the lower end is immersed in the molten steel, and ensuring that the height difference between the first argon gas hole and the top of the crystallizer is 30-50mm.

[0059] S2. The argon port at the top of the wire feeder is connected to the argon blowpipe, which is connected to the argon supply equipment. The argon supply equipment is started to introduce argon into the argon delivery channel of the wire feeder. The total flow rate and pressure of the argon are controlled to be 3-4 atmospheres. Argon is injected directionally through 3-4 argon holes to form an annular inert gas protection zone above the protective slag and around the wire feeder. The rare earth wire feeding speed is matched with the continuous casting billet pulling speed to ensure that rare earth elements are evenly distributed in the molten steel.

[0060] Argon gas enters the annular sealed cavity of the wire feeder shell through the argon gas port at the top of the wire feeder. The argon gas inside the cavity is arranged downwards at 30°-60° with 3-4 inclined openings with a diameter of Φ4.5mm and the axis of the openings being inclined downwards towards the outer wall of the rare earth wire, forming a protective argon gas layer around the rare earth wire.

[0061] Among them, the ejected argon gas flows downward along the annular gap between the rare earth wire and the inner hole of the wire feeder, and is discharged from the bottom outlet of the wire feeder. It enters the internal space of the crystallizer below. In the area above the surface of the molten steel in the crystallizer, a portion of the argon gas surrounds the rare earth wire that is about to melt into the molten steel to isolate it from the air. A small amount of argon gas immerses into the surface of the molten steel in the crystallizer along with the rare earth wire.

[0062] S3. Maintain a continuous argon injection state and feed rare earth wire into the molten steel in the crystallizer at a uniform speed through the wire feeder. The rare earth wire dissolves uniformly in the molten steel, and performs alloying and inclusion modification treatment on the molten steel.

[0063] S4. Throughout the wire feeding and continuous casting process, maintain an argon supply pressure of 3-4 atmospheres to continuously isolate the external air from the molten steel surface in the crystallizer, inhibiting air oxidation of the molten steel until the single batch wire feeding and billet casting process is completed.

[0064] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0065] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A device for protective addition of rare earth wires to a crystallizer, preventing splashing and oxidation of molten steel, characterized in that: Includes a wire feeding platform (1), on which a wire feeder (2) is provided. The wire feeder (2) is vertically connected to the wire feeding platform (1) in a vertical through-type structure. The upper end of the wire feeder (2) extends into the air, and the lower end of the wire feeder (2) extends into the molten steel inside the crystallizer (3). The wire feeder (2) has an argon gas passage (4) on the lower part of the exposed protective slag. The upper end of the wire feeder (2) has an argon gas port (5), which is connected to an argon gas blowing pipe with a diameter of 4-7 mm. The outer diameter of the wire feeder (2) is 15-50 mm.

2. The crystallizer protective rare earth wire addition device and anti-splash and anti-steel oxidation device according to claim 1, characterized in that: The height of the wire feeder (2) in the vertical direction is 200-750mm; The cross-sectional shape of the wire feeder (2) is an inverted "7" shape.

3. The crystallizer protective rare earth wire addition device and anti-splash and anti-steel oxidation device according to claim 2, characterized in that: The peripheral cavity of the wire feeder (2) is fixedly connected to the wire feeder (2) in the vertical direction. The wire feeder (2) has a wire feeding channel (6) in the center. The wire feeder (2) and the peripheral cavity form an annular cavity (8). Rare earth wire (7) is placed in the wire feeding channel. The wire feeder (2) is a high temperature resistant and oxidation-resistant rare earth wire feeder. It is made of zirconium oxide material or other materials with a melting point ≥1600℃ to make a high temperature resistant conduit. The conduit is embedded with alloy tubes of the same or different materials with a melting point ≥1600℃.

4. The crystallizer protective rare earth wire addition device and anti-splash and anti-steel oxidation device according to claim 3, characterized in that: The wire feeder (2) has argon gas holes (4) arranged at intervals in the vertical direction, and the wire feeding channel (6) at the junction of the vertical and inclined directions of the wire feeder (2) has a rounded corner structure.

5. The crystallizer protective rare earth wire addition device and anti-splash and anti-steel oxidation device according to claim 4, characterized in that: The wire feeding platform (1) is a height-adjustable wire feeding platform, and the wire feeding platform (1) is set within a range of 5-20mm from the outer surface of the sprue; A positioning frame (9) is fixedly installed on the outer cavity of the wire feeder (2) and is fixedly connected to the wire feeder (2). The positioning frame (9) is connected to the wire feeding platform (1).

6. The crystallizer protective rare earth wire addition device and anti-splash and anti-steel oxidation device according to claim 5, characterized in that: The angle between the tilting direction of the wire feeder (2) and the horizontal line is in the range of 10-60°, wherein the length of the tilting direction of the wire feeder (2) is 2000-5000mm.

7. The crystallizer protective rare earth wire addition device and anti-splash and anti-steel oxidation device according to claim 6, characterized in that: The argon gas passages (4) are spaced along the wire feeder (2). The opening position of the first argon gas passage (4) is 30-50 mm higher than the top of the crystallizer (3). The center distance between two adjacent argon gas passages (4) is 40-70 mm.

8. The crystallizer protective rare earth wire addition device and anti-splash and anti-steel oxidation device according to claim 7, characterized in that: The diameter of each argon passage (4) is 2.5-8 mm, and the angle between each argon passage (4) and the horizontal direction is 30°-60°.

9. The crystallizer protective rare earth wire addition device and anti-splash and anti-steel oxidation device according to claim 8, characterized in that: The argon gas passage (4) is evenly distributed along the circumference of the wire feeder, and the argon gas output direction is towards the molten steel surface of the crystallizer (3).

10. A method for applying a crystallizer protective device that incorporates rare earth wires and prevents splashing and oxidation of molten steel, characterized in that, Includes the following steps: S1. During continuous casting production, the vertical part of the wire feeder is installed on the wire feeding platform. The wire feeding platform is adjusted to make the lower end of the wire feeder reach the inside of the crystallizer, ensuring that the upper end of the rare earth wire feeder is in the air and the lower end is immersed in the molten steel, and ensuring that the height difference between the first argon gas hole and the top of the crystallizer is 30-50mm. S2. The argon port at the top of the wire feeder is connected to the argon blowpipe, which is connected to the argon supply equipment. The argon supply equipment is started to introduce argon into the argon delivery channel of the wire feeder. The total flow rate and pressure of the argon are controlled to be 3-4 atmospheres. Argon is injected directionally through the three argon ports to form an annular inert gas protection zone above the protective slag and around the wire feeder. Argon gas enters the annular sealed cavity of the wire feeder shell through the argon gas port at the top of the wire feeder. The argon gas inside the cavity passes through 3-4 inclined openings with a diameter of Φ2.5-8mm and the axis of the openings is inclined downward at 30°-60° to the horizontal, and moves towards the outer wall of the rare earth wire descending towards the center, forming a protective argon gas layer around the rare earth wire. Among them, the ejected argon gas flows downward along the annular gap between the rare earth wire and the inner hole of the wire feeder, and is discharged from the bottom outlet of the wire feeder. It enters the internal space of the crystallizer below. In the area above the surface of the molten steel in the crystallizer, a portion of the argon gas surrounds the rare earth wire that is about to melt into the molten steel to isolate it from the air. A small amount of argon gas immerses into the surface of the molten steel in the crystallizer along with the rare earth wire. S3. Maintain a continuous argon injection state and feed rare earth wire into the molten steel in the crystallizer at a uniform speed through the wire feeder. The rare earth wire dissolves uniformly in the molten steel, and performs alloying and inclusion modification treatment on the molten steel. S4. Throughout the wire feeding and continuous casting process, maintain an argon supply pressure of 3-4 atmospheres to continuously isolate the external air from the molten steel surface in the crystallizer, inhibiting air oxidation of the molten steel until the single batch wire feeding and billet casting process is completed.

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