A high-end metal special material vacuum argon-oxygen refining device VODC furnace and a refining method thereof

Abstract

This invention provides a high-end vacuum argon-oxygen refining apparatus (VODC furnace) for special metal materials and its refining method, belonging to the technical field of metallurgical refining equipment. It solves the problems of complex structure and high manufacturing and production costs associated with existing VOD furnace vacuum systems. This invention separates the vacuum system from the blowing system through modular design, employs a movable vacuum sealing structure and optimized furnace design, achieving a significant reduction in equipment and production costs. The refining method, by controlling the vacuum degree, oxygen blowing parameters, and stirring intensity, reduces non-metallic inclusions in the steel, achieving a hydrogen content of less than 1.5 × 10⁻⁶. ‑6 Oxygen content less than 2.0 × 10 ‑5 The chromium recovery rate in stainless steel reaches 98%-99%, and the refined steel possesses superior properties. Production efficiency is significantly improved while ensuring product quality. Compared with traditional equipment, this invention reduces equipment investment costs by more than 30%, shortens the refining cycle by 25%, and reduces energy consumption by 20%, making it particularly suitable for small-batch, multi-variety production of high-end specialty metal materials.

Description

Technical Field

[0001] This invention belongs to the technical field of metallurgical refining equipment, specifically relating to a high-end metal special material vacuum argon-oxygen refining device VODC furnace and its refining method. This furnace has the functions of both an AOD furnace and a VOD furnace. Background Technology

[0002] High-end metal special materials such as ultra-low carbon stainless steel and nickel-based alloys require precise control of chemical composition and gas content during production. Currently, the commonly used VOD (vacuum oxygen blowing decarburization) furnace and AOD (argon oxygen decarburization) furnace have the following technical defects: (1) high equipment investment cost, especially the expensive vacuum system; (2) long refining cycle, low production efficiency, and high production cost; (3) poor adaptability to small-batch, multi-variety special material production; (4) high energy consumption and high operating cost.

[0003] The improved VOD furnaces proposed in related studies have complex vacuum system structures and still have high manufacturing costs. Other studies have improved refining efficiency by optimizing oxygen blowing methods, but have not effectively solved the equipment cost problem. Therefore, there is an urgent need to develop a new type of refining equipment that can both guarantee refining quality and significantly reduce equipment costs and operating expenses. Summary of the Invention

[0004] The primary objective of this invention is to provide a low-cost, high-end metal special material vacuum argon-oxygen refining apparatus (VODC furnace). Through structural innovation and system optimization, it significantly reduces equipment manufacturing and operating costs while ensuring refining quality. Another objective of this invention is to provide a refining method based on the aforementioned apparatus. By optimizing process parameters and operating procedures, it improves refining efficiency, shortens the production cycle, and reduces production costs, thereby addressing the problems of complex structure, high manufacturing costs, and high production costs associated with existing VOD furnace vacuum systems.

[0005] The technical solution of the present invention is: a high-end metal special material vacuum argon-oxygen refining device VODC furnace, including a vacuum pump group system, a gas processing system, an argon-oxygen gas distribution system, a VODC furnace body system and a vacuum furnace cover system; The VODC furnace body system includes a VODC furnace shell or an AOD furnace shell. The VODC furnace shell or AOD furnace shell is equipped with a support flange, which is used to install the furnace shell onto a furnace shell support ring. The furnace shell support ring is connected to the tilting drive mechanism and fixed to the support base. The vacuum furnace cover system includes a track and columns for a vacuum cover transport flatcar used to seal the top of the VODC furnace shell or AOD furnace shell. The vacuum cover transport flatcar track is provided with, from bottom to top, a VODC furnace vacuum cover, a vacuum extraction pipe, and a vacuum cover transport flatcar. The vacuum cover transport flatcar is equipped with an oxygen lance lifting mechanism and a lifting oxygen lance. The vacuum cover transport flatcar is also equipped with a vacuum cover lifting mechanism and an alloy material feeding bin.

[0006] As a further improvement of the present invention, the vacuum pump system includes a Roots pump, a screw pump, a vacuum valve, a vacuum pipeline, a flow and vacuum degree measuring device, and an exhaust gas silencing and emission device.

[0007] As a further improvement of the present invention, the gas handling system includes a telescopic joint, a gas cooler, a flame arrestor filter, a gravity dust collector, a membrane filter, a filter dust collector, a main vacuum valve, and a venting device.

[0008] As a further improvement of the present invention, the argon-oxygen gas mixing system includes an argon blowing device, a nitrogen blowing device, and an oxygen control device.

[0009] As a further improvement of the present invention, the VODC furnace shell is lined with magnesia-chrome refractory bricks with a thickness of 250-350mm, a furnace shell diameter of 2.8-3.5m, and a height of 4.0-5.0m.

[0010] As a further improvement of the present invention, the VODC furnace vacuum cover is a water-cooled sandwich structure and is made of 304 or 316 stainless steel.

[0011] A refining method for a high-end metal special material vacuum argon-oxygen refining device using a VODC furnace includes VOD (vacuum oxygen blowing decarburization process), VCD (vacuum carbon deoxidation process), VOH (vacuum oxygen blowing heating process), and VD (vacuum degassing process), specifically comprising the following steps: A. Refining steps for low-carbon and ultra-low-carbon stainless steel using VOD+VCD+VD process: Step 1: Prepare the initial molten steel by adding molten steel at a temperature of 1600-1680℃; Step 2: Vacuum oxygen blowing decarburization, vacuum degree is 2-8 kPa, oxygen flow rate is 100-200 m³ / h; reduction refining, adding reducing agent and alloying materials; total refining time is 40-60 min; Step 3: After refining, vacuum carbon deoxidation is performed, followed by vacuum degassing, and finally the steel is tapped. B. Carbon steel and general alloy steel are refined under vacuum using the VOH+VD process: Step 1: Prepare the initial molten steel by adding molten steel at a temperature of 1600-1680℃; Step 2: Vacuum oxygen blowing heating, with a vacuum degree of 2-8 kPa and an oxygen blowing flow rate of 100-200 m³ / h; Step 3: Vacuum degassing, and finally, steel output.

[0012] As a further improvement of the present invention, in step three of the refining process of low-carbon and ultra-low-carbon stainless steel, the reducing agent added during the reduction refining stage is 2.0-3.0 kg / ton of ferrosilicon and 1.0-1.5 kg / ton of aluminum granules.

[0013] As a further improvement of the present invention, when refining low-carbon, ultra-low-carbon stainless steel or carbon steel and general alloy steel, the final molten steel has a carbon content of ≤0.01% and a hydrogen content of ≤2ppm.

[0014] As a further improvement of the present invention, in step three of the refining of low-carbon and ultra-low-carbon stainless steel, the argon gas stirring intensity at the bottom of the furnace during the refining process is 0.02-0.05 Nm³ / min·t.

[0015] The beneficial effects of this invention are as follows: Compared with the prior art, the present invention has the following significant advantages: 1. The equipment manufacturing cost is reduced by more than 30%, mainly due to the simplification of structure and modular design, which eliminates the VOD furnace shell and steam boiler and its jet pump system; 2. The refining cycle is shortened by 25%, and the production efficiency is significantly improved. The VODC furnace refining method can speed up the smelting process and eliminate intermediate subcontracting and steam production processes, thereby increasing the production capacity of the VODC furnace. 3. Energy consumption is reduced by 20%, and operating costs are significantly reduced. No steam boiler is needed, saving natural gas, water, and related equipment start-up costs, personnel costs, and spare parts costs. Vacuum refining can reduce the oxidation loss of alloying elements. It is highly adaptable and can meet the production needs of high-end special materials in small batches and multiple varieties, thus reducing operating costs. 4. The product quality is stable, and the gas content in molten steel can be controlled below 2 ppm. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall system composition of the present invention; Figure 2 This is a schematic diagram of the VODC furnace body system and vacuum furnace cover system in this invention; Figure 3 This is a schematic diagram of the working principle of the blowing system in this invention; Figure 4This is a refining process flow diagram according to an embodiment of the present invention.

[0017] In the diagram: 1-Vacuum pump system; 2-Gas handling system; 3-Argon-oxygen gas mixing system; 4-VODC furnace body system; 5-Vacuum furnace cover system; 11-Support base; 12-Tilting drive mechanism; 13-VODC furnace shell; 14-Furnace shell support ring; 15-Vacuum cover transport flatcar track and column; 6-VODC furnace vacuum cover; 7-Vacuum extraction pipe; 8-Vacuum cover transport flatcar; 9-Furnace top oxygen lance lifting mechanism; 10-Furnace top lifting oxygen lance; 111-Vacuum cover lifting mechanism; 112-Alloy material charging bin. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to the embodiments.

[0019] like Figures 1-4 As shown, a high-end metal special material vacuum argon-oxygen refining device VODC furnace includes a vacuum pump group system 1, a gas processing system 2, an argon-oxygen gas distribution system 3, a VODC furnace body system 4, and a vacuum furnace cover system 5. Vacuum pump system 1 includes a Roots pump, a screw pump, a vacuum valve, vacuum pipelines, flow and vacuum measurement devices, and exhaust gas silencing and emission devices, which enable the VODC furnace to be evacuated as required. Vacuum pump system 1 adopts a three-stage mechanical pump set, and the ultimate vacuum degree can be 0.02-1.0 Pa.

[0020] Gas handling system 2 includes expansion joints, gas coolers, flame arrestor filters, gravity dust collectors, membrane filters, filter dust collectors, main vacuum valves, and venting devices to achieve gas cooling, purification, filtration, and venting.

[0021] Argon-oxygen gas mixing system 3: It consists of an argon blowing device, a nitrogen blowing device, and an oxygen control device, which realizes accurate control of the pressure and flow rate of argon, nitrogen, and oxygen to meet the requirements of argon-oxygen refining.

[0022] VODC furnace body system 4: includes VODC furnace shell 13 and furnace shell support ring 14, the furnace shell support ring 14 achieves precise rotation control through support base 11 and tilting drive mechanism 12; Vacuum furnace cover system 5: including vacuum cover transport flatcar track and column 15, VODC furnace vacuum cover 6, vacuum extraction pipeline 7, vacuum cover transport flatcar 8, furnace top oxygen lance lifting mechanism 9, furnace top lifting oxygen lance 10, vacuum cover walking and lifting mechanism 111, alloy material feeding bin 112, to realize the rapid movement of VODC furnace vacuum cover 6 and precise material feeding under vacuum conditions.

[0023] This furnace body can alternate between VODC furnace shell 13 and AOD furnace shell. If AOD furnace shell is selected, the VODC furnace vacuum cover 6 can be placed at the steel tapping position away from the furnace shell support ring 14. At the same time, air guns are set on the side wall of AOD furnace shell. The side wall air guns are arranged near the furnace bottom area, and the furnace bottom air guns are arranged in the center area of ​​the furnace bottom. Four air blowing holes are set (three on the side wall and one on the furnace bottom), which can alternately blow in oxygen, argon and nitrogen. The blowing method is selected according to the VODC process or AOD process.

[0024] A refining method for a high-end metal special material vacuum argon-oxygen refining device using a VODC furnace is as follows: Reducing the pressure allows some components (H, N, Zn, Pb, O, C) in the molten metal pool to achieve lower equilibrium values ​​than under normal pressure, enhancing gas stirring intensity and ensuring thorough mixing of the steel slag (dehydrogenation, denitrification, desulfurization, deoxidation, and inclusion separation). When molten steel passes through the VODC furnace: → the vacuum ladle cover is moved to the vacuum treatment station → the vacuum cover is lowered onto the VODC furnace body → the vacuum cover is closed → the vacuum pump is started to create a vacuum → deep decarburization begins when the vacuum level reaches 2 kPa → after 10-20 minutes of deep decarburization → when the carbon content in the molten steel meets the requirements → alloying and reducing agents are added → high-vacuum reduction treatment is performed → after treatment, the main vacuum valve is closed → the vacuum is broken → the vacuum cover is lifted → temperature measurement and sampling are conducted → the vacuum cover car is moved to the tapping station → ready for tapping.

[0025] like Figure 4 As shown, when refining low-carbon and ultra-low-carbon stainless steel, the process of VOD (vacuum oxygen blowing decarburization process) + VCD (vacuum carbon deoxidation process) + VD (vacuum degassing process) is adopted. When refining carbon steel and general alloy steel in a VODC furnace, the process of VOH (vacuum oxygen blowing heating process) + VD (vacuum degassing process) is adopted.

[0026] The innovative aspects of the technical solution of this invention are: (1) The modular design separates the vacuum pump system 1 from the blowing system and enables rapid switching of the vacuum cover through a transport flatcar, which greatly improves the equipment utilization rate; (2) Optimize the furnace structure and integrate the VOD vacuum refining function and the AOD blowing function into the same device; (3) The innovative use of a movable vacuum sealing structure simplifies the complexity of the vacuum system.

[0027] Example 1 In this embodiment, a high-end metal special material vacuum argon-oxygen refining device VODC furnace includes a vacuum pump group system 1, a gas processing system 2, an argon-oxygen gas distribution system 3, a VODC furnace body system 4, and a vacuum furnace cover system 5. The VODC furnace body system 4 includes a VODC furnace shell 13, which is equipped with a furnace shell support flange. The VODC furnace shell 13 is mounted on a furnace shell support ring 14 via the support flange. The furnace shell support ring 14 is connected to a tilting drive mechanism 12 and fixed on a support base 11. The vacuum furnace cover system 5 includes a track and column 15 for a vacuum cover transport flatcar used to seal the top of the VODC furnace shell 13 for sealing the VODC furnace shell or AOD furnace shell. The vacuum cover transport flatcar 8 is provided with a VODC furnace vacuum cover 6, a vacuum extraction pipe 7, and the vacuum cover transport flatcar 8 in sequence from bottom to top. The vacuum cover transport flatcar 8 is equipped with a furnace top oxygen lance lifting mechanism 9 and a furnace top lifting oxygen lance 10. The vacuum cover transport flatcar 8 is also equipped with a vacuum cover lifting mechanism 111 and an alloy material charging bin 112.

[0028] The VODC furnace shell 13 is lined with magnesia-chrome refractory bricks, with a thickness of 250 mm, a diameter of 2.8 m, and a height of 4.0 m. The VODC furnace vacuum cover 6 is a water-cooled sandwich structure made of 304 stainless steel. The VODC furnace shell 13 has no side lances or side lance holes, but only bottom blowing holes at the bottom of the furnace body for connecting to the nitrogen / argon bottom blowing system.

[0029] Vacuum pump system 1 includes a Roots pump, screw pump, vacuum valve, vacuum piping, flow and vacuum measurement devices, and exhaust gas silencing and emission devices. Gas handling system 2 includes an expansion joint, gas cooler, flame arrestor filter, gravity dust collector, membrane filter, filter dust collector, main vacuum valve, and air purging device. Argon-oxygen gas mixing system 3 includes an argon blowing device, a nitrogen blowing device, and an oxygen control device.

[0030] Taking refined ultra-low carbon stainless steel (00Cr17Ni14Mo2) as an example, the specific process steps and parameters are as follows: Step 1: Prepare the initial molten steel by adding molten steel at a temperature of 1600℃; Step 2: Vacuum oxygen blowing decarburization, vacuum degree is 2kPa, oxygen flow rate is 100m³ / h; reduction refining, adding reducing agent and alloying materials; total refining time is 40min; During the reduction refining stage, the reducing agent added is 2.0 kg / ton of ferrosilicon and 1.0 kg / ton of aluminum granules; the argon stirring intensity at the furnace bottom during the refining process is 0.02 Nm³ / min·t. Alloying: Adding alloying materials such as ferromolybdenum and ferrochrome, and precisely controlling the composition; Step 3: After refining, vacuum carbon deoxidation is carried out, followed by vacuum degassing, and finally the steel is tapped; the final molten steel has a carbon content of ≤0.01% and a hydrogen content of ≤2ppm.

[0031] Example 2 In this embodiment, a high-end metal special material vacuum argon-oxygen refining device VODC furnace includes a vacuum pump group system 1, a gas processing system 2, an argon-oxygen gas distribution system 3, a VODC furnace body system 4, and a vacuum furnace cover system 5. The VODC furnace body system 4 includes a VODC furnace shell 13, which is equipped with a furnace shell support flange. The VODC furnace shell 13 is mounted on a furnace shell support ring 14 via the support flange. The furnace shell support ring 14 is connected to a tilting drive mechanism 12 and fixed on a support base 11. The vacuum furnace cover system 5 includes a track and column 15 for a vacuum cover transport flatcar used to seal the top of the VODC furnace shell 13 for sealing the VODC furnace shell or AOD furnace shell. The vacuum cover transport flatcar 8 is provided with a VODC furnace vacuum cover 6, a vacuum extraction pipe 7, and the vacuum cover transport flatcar 8 in sequence from bottom to top. The vacuum cover transport flatcar 8 is equipped with a furnace top oxygen lance lifting mechanism 9 and a furnace top lifting oxygen lance 10. The vacuum cover transport flatcar 8 is also equipped with a vacuum cover lifting mechanism 111 and an alloy material charging bin 112.

[0032] The VODC furnace shell 13 is lined with magnesia-chrome refractory bricks, with a thickness of 300 mm, a diameter of 3.1 m, and a height of 4.5 m. The VODC furnace vacuum cover 6 is a water-cooled sandwich structure made of 316 stainless steel. The VODC furnace shell 13 has no side lances or side lance holes, but only bottom blowing holes at the bottom of the furnace body for connecting to the nitrogen / argon bottom blowing system.

[0033] Vacuum pump system 1 includes a Roots pump, screw pump, vacuum valve, vacuum piping, flow and vacuum measurement devices, and exhaust gas silencing and emission devices. Gas handling system 2 includes an expansion joint, gas cooler, flame arrestor filter, gravity dust collector, membrane filter, filter dust collector, main vacuum valve, and air purging device. Argon-oxygen gas mixing system 3 includes an argon blowing device, a nitrogen blowing device, and an oxygen control device.

[0034] Taking refined two-dimensional stainless steel (S32507) as an example, the specific process steps and parameters are as follows: Step 1: Prepare the initial molten steel by adding molten steel at a temperature of 1640℃; Step 2: Vacuum oxygen blowing decarburization, vacuum degree is 5 kPa, oxygen flow rate is 150 m³ / h; reduction refining, adding reducing agent and alloying materials; total refining time is 50 min; During the reduction refining stage, the reducing agent added is 2.5 kg / ton of ferrosilicon and 1.2 kg / ton of aluminum granules; the argon stirring intensity at the furnace bottom during the refining process is 0.04 Nm³ / min·t. Alloying: Adding alloying materials such as ferromolybdenum and ferrochrome, and precisely controlling the composition; Step 3: After refining, vacuum deoxidation is performed, followed by vacuum degassing, and finally the steel is tapped; the final molten steel has a carbon content of ≤0.01% and a hydrogen content of ≤2ppm.

[0035] Example 3 In this embodiment, a high-end metal special material vacuum argon-oxygen refining device VODC furnace includes a vacuum pump group system 1, a gas processing system 2, an argon-oxygen gas distribution system 3, a VODC furnace body system 4, and a vacuum furnace cover system 5. The VODC furnace body system 4 includes a VODC furnace shell 13, which is equipped with a furnace shell support flange. The VODC furnace shell 13 is mounted on a furnace shell support ring 14 via the support flange. The furnace shell support ring 14 is connected to a tilting drive mechanism 12 and fixed on a support base 11. The vacuum furnace cover system 5 includes a track and column 15 for a vacuum cover transport flatcar used to seal the top of the VODC furnace shell 13 for sealing the VODC furnace shell or AOD furnace shell. The vacuum cover transport flatcar 8 is provided with a VODC furnace vacuum cover 6, a vacuum extraction pipe 7, and the vacuum cover transport flatcar 8 in sequence from bottom to top. The vacuum cover transport flatcar 8 is equipped with a furnace top oxygen lance lifting mechanism 9 and a furnace top lifting oxygen lance 10. The vacuum cover transport flatcar 8 is also equipped with a vacuum cover lifting mechanism 111 and an alloy material charging bin 112.

[0036] The AOD furnace shell is lined with magnesia-chrome refractory bricks with a thickness of 350mm, a furnace shell diameter of 3.5m, and a height of 5.0m. When using the AOD furnace shell, in the early stage of refining, the VODC furnace vacuum cover 6 can be parked at the tapping station far away from the refining furnace area. In the later stage of refining, the VODC furnace vacuum cover 6 can be moved down to the AOD furnace shell support flange. At the same time, air guns are installed on the side wall of the AOD furnace shell. The furnace side air guns are made of special ceramic materials and are arranged on the side wall near the furnace bottom area. A total of 3 air blowing holes are set to realize the alternating blowing of oxygen, argon, and nitrogen.

[0037] Vacuum pump system 1 includes a Roots pump, screw pump, vacuum valve, vacuum piping, flow and vacuum measurement devices, and exhaust gas silencing and emission devices. Gas handling system 2 includes an expansion joint, gas cooler, flame arrestor filter, gravity dust collector, membrane filter, filter dust collector, main vacuum valve, and air purging device. Argon-oxygen gas mixing system 3 includes an argon blowing device, a nitrogen blowing device, and an oxygen control device.

[0038] Taking refined ultra-low carbon stainless steel (00Cr17Ni14Mo2) as an example, the specific process steps and parameters are as follows: Step 1: Prepare the initial molten steel by adding molten steel at a temperature of 1680℃; Step 2: Vacuum oxygen blowing decarburization, vacuum degree is 8 kPa, oxygen flow rate is 200 m³ / h; reduction refining, adding reducing agent and alloying materials; total refining time is 60 min; During the reduction refining stage, the reducing agent added is 3.0 kg / ton of ferrosilicon and 1.5 kg / ton of aluminum granules; the argon stirring intensity at the furnace bottom during the refining process is 0.05 Nm³ / min·t. Alloying: Adding alloying materials such as ferromolybdenum and ferrochrome, and precisely controlling the composition; Step 3: After refining, vacuum deoxidation is performed, followed by vacuum degassing, and finally the steel is tapped; the final molten steel has a carbon content of ≤0.01% and a hydrogen content of ≤2ppm.

[0039] The experimental data for Examples 1-3 are shown in Table 1.

[0040] As shown in Table 1, the VODC furnace of the vacuum argon-oxygen refining unit can achieve the following advantages.

[0041] Advantage 1: Reduced energy consumption. VODC vacuum refining can be carried out at lower oxygen partial pressures, thus reducing argon consumption. Compared to traditional VOD furnaces, VODC vacuum refining reduces the frequency of using overhead cranes and ladle transfer carts, lowering power consumption. VODC vacuum refining eliminates the need for LF furnace refining, further reducing electricity consumption for molten steel and general power. VODC vacuum refining eliminates the need for steam boilers, saving on natural gas, water, and related equipment operating costs, personnel costs, and spare parts costs. This reduces the fixed cost per unit of product.

[0042] Advantage 2: Reduced loss of alloying elements. Vacuum refining in a VODC furnace can reduce the oxidation loss of alloying elements such as chromium, improve the utilization rate of valuable raw materials, and reduce raw material consumption costs.

[0043] Advantage 3: Improved production efficiency. Vacuum refining in a VODC furnace can accelerate the smelting speed, eliminating intermediate subcontracting and steam boiler processes, thus increasing the production capacity of the VODC furnace. The refining time is shortened from 160 minutes to 70 minutes, significantly improving production efficiency: the original process was LF furnace (90 minutes) + VOD furnace (70 minutes), now it is VODC furnace (50-70 minutes).

[0044] Advantage 4: Reduced overall costs. A comparison is made based on the refining of 300 series stainless steel, as shown in Table 2. .

Claims

1. A VODC furnace for vacuum argon-oxygen refining of high-end metal special materials, characterized in that: It includes a vacuum pump system (1), a gas handling system (2), an argon-oxygen gas mixing system (3), a VODC furnace body system (4), and a vacuum furnace cover system (5). The VODC furnace system (4) includes a VODC furnace shell (13), which is mounted on a furnace shell support ring (14). The furnace shell support ring (14) is connected to a tilting drive mechanism (12) and fixed on a support base (11). The vacuum furnace cover system (5) includes a vacuum cover transport flatcar track and column (15) connected to the top of the VODC furnace shell (13) for sealing the VODC furnace shell (13). The vacuum cover transport flatcar track and column (15) are provided with a VODC furnace vacuum cover (6), a vacuum extraction pipe (7), and a vacuum cover transport flatcar (8) from bottom to top. The vacuum cover transport flatcar (8) is provided with a furnace top oxygen lance lifting mechanism (9) and a furnace top lifting oxygen lance (10). The vacuum cover transport flatcar (8) is also provided with a vacuum cover lifting mechanism (111). The top of the VODC furnace system (4) is also provided with an alloy material feeding bin (112).

2. The VODC furnace for high-end metal special material vacuum argon-oxygen refining apparatus according to claim 1, characterized in that: The vacuum pump system (1) includes a Roots pump, a screw pump, a vacuum valve, a vacuum pipeline, a flow and vacuum measurement device, and a tail gas silencing and emission device.

3. The VODC furnace for high-end metal special material vacuum argon-oxygen refining apparatus according to claim 1, characterized in that: The gas processing system (2) includes a telescopic joint, a gas cooler, a flame arrestor filter, a gravity dust collector, a membrane filter, a filter dust collector, a main vacuum valve, and a venting device.

4. The VODC furnace for vacuum argon-oxygen refining of high-end metal special materials according to claim 1, characterized in that: The argon-oxygen gas mixing system (3) includes an argon blowing device, a nitrogen blowing device, and an oxygen control device.

5. The VODC furnace for vacuum argon-oxygen refining of high-end metal special materials according to claim 1, characterized in that: The VODC furnace shell (13) is lined with magnesia-chrome refractory bricks with a thickness of 250-350 mm, a furnace shell diameter of 2.8-3.5 m, and a height of 4.0-5.0 m.

6. The VODC furnace for vacuum argon-oxygen refining of high-end special metal materials according to claim 1, characterized in that: The VODC furnace vacuum cover (6) is a water-cooled sandwich structure and is made of 304 or 316 stainless steel.

7. The refining method of a VODC furnace in a vacuum argon-oxygen refining apparatus for high-end special metal materials according to any one of claims 1-6, characterized in that: This includes vacuum oxygen blowing decarburization process, vacuum carbon deoxidation process, vacuum oxygen blowing heating process, and vacuum degassing process, specifically including the following steps: A. The refining process for low-carbon and ultra-low-carbon stainless steel employs a combination of vacuum oxygen blowing decarburization, vacuum carbon deoxidation, and vacuum degassing. Step 1: Prepare the initial molten steel by adding molten steel at a temperature of 1600-1680℃; Step 2: Vacuum oxygen blowing decarburization, vacuum degree is 2-8 kPa, oxygen flow rate is 100-200 m³ / h; reduction refining, adding reducing agent and alloying materials; total refining time is 40-60 min; Step 3: After refining, vacuum carbon deoxidation is performed, followed by vacuum degassing, and finally the steel is tapped. B. The refining steps for carbon steel and general alloy steel using vacuum oxygen blowing heating + vacuum degassing process are as follows: Step 1: Prepare the initial molten steel by adding molten steel at a temperature of 1600-1680℃; Step 2: Vacuum oxygen blowing heating, with a vacuum degree of 2-8 kPa and an oxygen blowing flow rate of 100-200 m³ / h; Step 3: Vacuum degassing, and finally, steel output.

8. The refining method of a VODC furnace in a vacuum argon-oxygen refining apparatus for high-end special metal materials according to claim 7, characterized in that: In step three of the refining process for low-carbon and ultra-low-carbon stainless steel, the reducing agent added during the reduction refining stage is 2.0-3.0 kg / ton of ferrosilicon and 1.0-1.5 kg / ton of aluminum granules.

9. The refining method of a VODC furnace in a vacuum argon-oxygen refining apparatus for high-end special metal materials according to claim 8, characterized in that: When refining low-carbon, ultra-low-carbon stainless steel or carbon steel and general alloy steel, the final molten steel has a carbon content of ≤0.01% and a hydrogen content of ≤2ppm.

10. The refining method of a VODC furnace in a vacuum argon-oxygen refining apparatus for high-end special metal materials according to claim 9, characterized in that: In step three of the refining process of low-carbon and ultra-low-carbon stainless steel, the argon stirring intensity at the bottom of the furnace during the refining process is 0.02-0.05 Nm³ / min·t.

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