A device and method for preparing a low-hydrogen stainless steel electroslab ingot

Abstract

The application discloses a kind of preparation device and preparation method of low hydrogen stainless steel electroslag ingot, belong to special metallurgy technical field.The preparation device of low hydrogen stainless steel electroslag ingot of the present application, including crystallizer, the lower part of the crystallizer is equipped with the heating cavity that water slit is surrounded along circumference, heating cavity is not connected annular structure, namely C character shape structure, and its inside is equipped with double-channel heating resistance wire, for heating arc plate, consumable electrode and crystallizer inner wall.The present application can realize consumable electrode, arc plate, the heating of crystallizer and the removal of the condensate water on the surface of three simultaneously, reduce the moisture content for electroslag remelting system, thereby effectively reduce the porosity and hydrogen content of electroslag ingot, so that hydrogen content is stably controlled at ≤2ppm.

Description

Technical Field

[0001] This invention belongs to the field of special steel smelting technology, and more specifically, relates to a preparation apparatus and method for low-hydrogen stainless steel electroslag ingots. Background Technology

[0002] Over the past few decades, the field of electroslag remelting has gradually perfected its theoretical foundation research in slag systems, remelting process control, and numerical simulation. Today, electroslag remelting technology is a composite refining technology integrating metal melting, purification, and cooling solidification. Electroslag steel produced using electroslag remelting is characterized by high cleanliness, uniform element distribution, and high microstructure density. Furthermore, the final processed products have significant advantages in mechanical properties and service life compared to other refining methods, making a significant contribution to the manufacturing of high-end products. Electroslag casting products can also closely approximate the final product form, with high material utilization, playing an indispensable role in the production of key equipment components.

[0003] However, the drawbacks of electroslag remelting cannot be ignored. The most significant is the excessive hydrogen content and even porosity at the bottom of the electroslag ingot. This is due to the ineffective removal of moisture from the electroslag remelting system. For example, if condensate from the consumable electrode, crystallizer, or slag surface is not effectively removed, moisture will remain in the crystallized electroslag ingot, leading to excessive hydrogen content and porosity. Therefore, preventing porosity and excessive hydrogen content at the bottom of the electroslag ingot during electroslag remelting is crucial.

[0004] A search revealed that Chinese invention patent 201910784958.7 discloses a baking device for a cast steel crystallizer. This device uses a baking unit located at the bottom of the crystallizer to heat the crystallizer with hot air generated during heating. Another example is Chinese invention patent 201210191017.0, which discloses a method for controlling the hydrogen content of molten steel in electroslag remelting. This application uses a method of blowing dry hot air into the remelting process to remove condensate from the surface of the crystallizer. However, these technologies suffer from the drawback of hot air having a relatively low specific gravity, making it difficult to completely eliminate the humid air inside the crystallizer. In this situation, even after cooling water is introduced into the crystallizer, condensate will still form on its surface, and a layer of condensate will also precipitate on the electrode surface. Even if the condensate in the crystallizer can be removed, the condensate introduced by the electrodes will still lead to porosity at the bottom of the electroslag ingot and an increase in hydrogen content. Furthermore, when the crystallizer is transferred from the baking unit to the work station by a crane, condensate will re-accumulate due to the cold air. At the same time, none of the above applications consider the impact of condensate on the electrode surface and the bottom water tank surface during the initial stage of remelting.

[0005] In summary, existing electroslag remelting systems cannot effectively remove moisture from the electrode surface, bottom water tank surface, and crystallizer surface, resulting in numerous pores and high hydrogen content at the bottom of the electroslag ingot. Therefore, there is an urgent need to design an electroslag remelting device that can effectively remove condensate from the electrode surface, bottom water tank surface, and crystallizer surface. Summary of the Invention

[0006] 1. The technical problem that the invention aims to solve

[0007] The purpose of this invention is to overcome the shortcomings of existing technologies where pores easily form at the bottom of electroslag ingots during electroslag remelting, leading to excessive hydrogen content. This invention provides a device and method for preparing low-hydrogen stainless steel electroslag ingots. By setting a heating chamber inside the crystallizer and installing a U-shaped resistance wire structure within the heating chamber to effectively heat the inner wall of the crystallizer, the arc-starting plate, and the consumable electrode, moisture can be effectively removed from the electrode surface and the crystallizer surface, preventing pores from forming at the bottom of the electroslag ingot and reducing the hydrogen content.

[0008] 2. Technical Solution

[0009] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0010] The present invention discloses a device for preparing low-hydrogen stainless steel electroslag ingots, comprising a crystallizer, wherein the lower part of the crystallizer is provided with a heating cavity surrounding the water gap in the circumferential direction, the heating cavity having a non-connected annular structure, i.e. a C-shaped structure, and having a dual-channel heating resistance wire inside for heating the arc-starting plate, the consumable electrode and the inner wall of the crystallizer.

[0011] This invention solves the problem that existing electroslag remelting systems cannot effectively remove moisture from the electrode and crystallizer surfaces, resulting in numerous pores and high hydrogen content at the bottom of the electroslag ingot. By setting up a heating chamber inside the crystallizer and installing dual-channel heating resistance wires inside the heating chamber to heat the inner wall of the crystallizer, the arc-starting plate, and the consumable electrode, the invention addresses this issue.

[0012] Furthermore, the dual-channel heating resistance wire includes a first channel and a second channel, both of which are formed by sequentially connecting parallel, arc-shaped resistance wires. Since the water vapor content varies at different heights of the crystallizer, the required heating temperature also differs. Therefore, this invention, by setting two channels, can control the heating temperature at different heights of the crystallizer, thus ensuring the heating effect. Further optimized, the first channel is located above the second channel, and the bottom end of the first channel and the top end of the second channel are both connected to a third terminal. The resistance value of the resistance wire in the first channel is greater than that in the second channel.

[0013] Furthermore, the heating chamber is equipped with an annular support plate, which also has a C-shaped structure, i.e., a non-closed annular structure. The annular support plate is made of insulating material, and its outer wall has locking ribs on both sides that engage with the heating chamber. Its inner wall is machined with a U-shaped groove that matches the dual-channel heating resistance wire, which is installed in the U-shaped groove. The annular support plate facilitates the installation of the dual-channel heating resistance wire and also protects the resistance wire, providing insulation to prevent short circuits between the energized resistance wire and the crystallizer, thus preventing damage.

[0014] Furthermore, an annular copper plate is provided on the side of the heating chamber near the water slit to facilitate heat conduction; the bottom end of the U-shaped groove is inclined, and the angle between it and the side wall of the annular copper plate is 20°~30°. Therefore, when cooling water is introduced into the crystallizer, the condensate generated in the heating chamber can be discharged to the bottom of the heating chamber, extending the service life of the resistance wire.

[0015] Furthermore, the crystallizer has an internal detection chamber located in the middle of the heating chamber. A temperature sensor is installed inside the detection chamber, with one end in contact with the inner wall of the crystallizer, for measuring the heating temperature of the crystallizer. The detection chamber is not connected to the water slits inside the crystallizer to prevent cooling water from eroding the temperature sensor. The other end of the temperature sensor and the dual-channel heating resistance wire are connected to a temperature control integrated box. The temperature of the crystallizer is measured by the temperature sensor, and the heating temperature of the first and second channels is controlled based on the measurement results.

[0016] Furthermore, the bottom of the crystallizer is machined with an annular groove, within which an annular flange is installed. The width of the annular groove is greater than the width of the heating chamber, thus sealing the heating chamber. The height of the heating chamber is one-third of the total height of the crystallizer, and the width of the water slit inside is 2-3 mm, exhibiting a structure that is wider at the top and narrower at the bottom. Using this water slit structure, only the bottom needs to be heated during operation. After heating to a certain temperature, remelting is performed. For the upper part, heating can be achieved using the temperature during remelting, eliminating the need to heat the entire crystallizer.

[0017] The present invention discloses a method for preparing low-hydrogen stainless steel electroslag ingots, which employs the preparation apparatus of the present invention, wherein heating is performed by a dual-channel heating resistance wire before the start of electroslag remelting.

[0018] Furthermore, the slag system used in electroslag remelting includes the following components by mass: 4-5 parts fluorite, 3-4 parts calcium aluminate, and 2-3 parts LF refining furnace waste slag.

[0019] It should be noted that, on the one hand, the present invention can effectively remove moisture from the electrode surface, the bottom water tank surface and the crystallizer surface by setting up the heating chamber. On the other hand, it also optimizes the slag system composition of electroslag remelting, which can further prevent the slag system itself from generating water vapor, resulting in porosity and high hydrogen content in the resulting castings. Therefore, it can effectively ensure the quality of the obtained electroslag remelting products.

[0020] Specifically, existing electroslag remelting slag systems typically contain free calcium oxide, which is highly hygroscopic. Therefore, the slag system itself contains a certain amount of moisture, which is transferred to the molten steel during the remelting process, increasing the oxygen content of the electroslag ingot. This application addresses this by adding a certain amount of LF refining furnace waste slag. Firstly, this waste slag contains a certain amount of calcium oxide, which exists in compound form and is not easily hygroscopic, thus effectively preventing the possibility of hydrogen addition to the molten steel during remelting. Secondly, the LF refining furnace waste slag undergoes high-temperature refining, resulting in extremely low hydrogen content, thus preventing hydrogen addition to the molten steel through the slag and ensuring the smelting of low-hydrogen stainless steel electroslag ingots. This application, through optimization of the crystallizer structure and the composition of the electroslag remelting slag system, ensures that the hydrogen content of the resulting stainless steel electroslag ingot is less than 2 ppm.

[0021] Furthermore, the fluorite contains ≥95% CaF2 and undergoes pre-melting treatment, during which calcium deoxidation is performed; the calcium aluminate composition is: Al2O3≥58%, CaO≥36%; the LF refining furnace slag composition is: CaO 50~60%; Al2O3 28~35%; MgO 4~6%; SiO2 8~12%.

[0022] Furthermore, before the electroslag remelting begins, the temperatures of the first and second resistance wires are raised to 240℃~260℃ and 190℃~220℃ respectively, and maintained at these temperatures for 10~15 minutes. The surface area requiring preheating near the bottom is larger, resulting in more water vapor. As the height increases, the preheating area decreases. Therefore, to ensure effective water vapor removal and better economic benefits, the first and second passages are controlled at different heating temperatures. The fluorite, calcium aluminate, and refining furnace slag have a particle size of 10~20mm. After mixing, they are baked at 800~850℃ for 6~8 hours, and the temperature of the slag added to the crystallizer is not lower than 300℃.

[0023] In summary, compared with existing known technologies, the technical solution provided by this invention can achieve the following significant effects:

[0024] (1) The present invention adopts an integrated heating device, which integrates the heating chamber into the crystallizer and heats it through the heating chamber of the crystallizer itself. This greatly reduces the time it takes for the heated crystallizer to move from the heating workbench to the remelting platform via the trolley, reduces the air cooling time of the crystallizer, and can effectively prevent the secondary formation of condensate on the surface of the crystallizer. At the same time, it greatly improves the remelting efficiency.

[0025] (2) By using a dual-channel heating resistance wire, and the resistance value of the first channel resistance wire is greater than that of the second channel resistance wire, the present invention can meet the requirements of setting different temperatures at different positions inside the crystallizer. At the same time, the heating temperature can be adjusted according to different air humidity to reduce power consumption.

[0026] (3) Based on the optimized design of the crystallizer structure, the present invention further designs the remelting slag system, which helps to further reduce the influence of water vapor and the hydrogen content of the obtained electroslag remelted ingot, thus ensuring product quality. Attached Figure Description

[0027] Figure 1 This is a three-dimensional structural schematic diagram of the apparatus for preparing low-hydrogen stainless steel electroslag ingots according to the present invention.

[0028] Figure 2 This is a cross-sectional view of the apparatus for preparing low-hydrogen stainless steel electroslag ingots according to the present invention.

[0029] Figure 3 This is a three-dimensional structural diagram of the support plate of the present invention;

[0030] Figure 4 This is a three-dimensional structural diagram of the dual-channel heating resistance wire of the present invention;

[0031] In the diagram: 1. Crystallizer; 2. Bottom water tank; 3. Connecting plate; 4. Arc-starting plate; 5. Consumable electrode; 6. Annular flange; 7. Quick-change bolt; 8. Temperature sensor; 9. Heating chamber; 11. Dual-channel heating resistance wire; 11-1. First passage; 11-2. Second passage; 11-3. First water inlet pipe; 11-4. Second water inlet pipe; 11-5. Circulating water outlet pipe; 12. Support plate; 1201. U-shaped groove; 13. Water gap; 14. Bracket; 15. Detection chamber; 16. Temperature control integrated box. Detailed Implementation

[0032] To further understand the content of this invention, the invention will be described in detail with reference to the embodiments.

[0033] Example 1

[0034] like Figure 1 , Figure 2As shown, this embodiment of the apparatus for preparing low-hydrogen stainless steel electroslag ingots includes a crystallizer 1, a bottom water tank 2 at the bottom of the crystallizer 1, a connecting plate 3 between the crystallizer 1 and the bottom water tank 2, and the crystallizer 1, the connecting plate 3 and the bottom water tank 2 are integrally connected by several quick-change bolts 7. The crystallizer 1 has a water slit 13 extending along its height direction inside, the width of the water slit is 2-3 mm and it has a structure that is wider at the top and narrower at the bottom. The lower part of the crystallizer 1 has a heating chamber 9 surrounding the water slit 13 circumferentially. The heating chamber 9 has a non-connected annular structure (C-shaped structure), its height is one-third of the total height of the crystallizer 1, and it has a dual-channel heating resistance wire 11 inside for heating the arc-starting plate 4, the consumable electrode 5 and the inner wall of the crystallizer; the bottom of the crystallizer 1 is machined with an annular groove, the width of which is greater than the width of the heating chamber 9, and an annular flange 6 is installed inside it for sealing the heating chamber 9.

[0035] This embodiment employs a "built-in" dual-channel direct heating method, which allows for simultaneous heating of the arc-starting plate, consumable electrode, and inner wall of the crystallizer. It also dries the humid air inside the crystallizer, comprehensively reducing moisture in the remelting system and effectively lowering the porosity and hydrogen content of the electroslag ingot. Furthermore, its heating effect is quick and convenient, making it particularly suitable for humid processing sites in the south and regions with long rainy seasons.

[0036] Specifically, such as Figure 4As shown, the dual-channel heating resistance wire 11 includes a first channel 11-1 and a second channel 11-2. Both the first channel 11-1 and the second channel 11-2 are formed by sequentially connecting arc-shaped resistance wires arranged in parallel vertically. The first channel 11-1 is located above the second channel 11-2, and the bottom end of the first channel 11-1 and the top end of the second channel 11-2 are both connected to a third terminal 11-5. The resistance value of the resistance wire in the first channel 11-1 is greater than that in the second channel 11-2. By adopting a dual-channel resistance wire structure, the heating temperature of the resistance wire can be controlled according to the different heights of the crystallizer, thereby meeting the different heating temperature requirements at different heights and further ensuring the water vapor removal effect. Furthermore, the crystallizer 1 has a detection chamber 15 located in the middle of the heating chamber 9. A temperature sensor 8 is installed inside the detection chamber, with one end in contact with the inner wall of the crystallizer, for measuring the heating temperature of the crystallizer. The other end of the temperature sensor 8 and the dual-channel heating resistance wire 11 are connected to the temperature control integrated box 16. Specifically, the first channel 11-1 is connected to the temperature control integrated box 16 through the first terminal 11-3 and the third terminal 11-5, and the second channel 11-2 is connected to the temperature control integrated box 16 through the second terminal 11-4 and the third terminal 11-5. The temperature sensor 8 can measure the temperature of the inner wall of the crystallizer and feed it back to the temperature control integrated box 16, thereby controlling the heating temperature of the first channel 11-1 and the second channel 11-2. It can also adjust the heating temperature according to different air humidity levels, reducing power consumption.

[0037] like Figure 2 , Figure 3 As shown, the heating chamber 9 is equipped with an annular support plate 12, which is made of insulating material. Its outer walls have locking ribs 14 that engage with the heating chamber 9, and its inner wall is machined with a U-shaped groove 1201 that matches the dual-channel heating resistance wire 11. The dual-channel heating resistance wire 11 is installed within the U-shaped groove 1201. The annular support plate 12 facilitates the installation of the dual-channel heating resistance wire 11 and provides insulation protection, preventing short circuits between the energized resistance wire and the crystallizer. Simultaneously, the inner wall of the heating chamber has a positioning groove, and the annular support plate 12 is installed through the gap fit between the locking ribs 14 and the positioning groove.

[0038] An annular copper plate is provided inside the heating chamber 9 near the water slit 13. One side of the heating chamber is connected to the copper inner wall and steel outer wall of the crystallizer through the annular copper plate, which is beneficial to the temperature conduction of the heating chamber. Furthermore, the bottom end of the U-shaped groove 1201 is inclined, and the angle between it and the side wall of the annular copper plate is 20°~30°. Therefore, when cooling water is introduced into the crystallizer, the condensate generated in the heating chamber can be easily discharged to the bottom of the heating chamber, thereby extending the service life of the resistance wire.

[0039] This embodiment describes a method for preparing low-hydrogen stainless steel electroslag ingots. Using the aforementioned preparation apparatus, heating is performed before electroslag remelting begins via a dual-channel heating resistance wire 11. The specific steps are as follows:

[0040] Step 1: First, peel off the outer layer of the stainless steel consumable electrode.

[0041] Step 2: Use a crane to transport the low-hydrogen stainless steel electroslag ingot preparation device to the designated work station and install the consumable electrode 5 in the crystallizer;

[0042] Step 3: Connect the inlet and outlet of the preparation device to the circuit using a quick-connect device;

[0043] Step 4: The temperature control integrated box controls the first and second channel resistance wires to work, and controls the temperature of the first and second channel resistance wires to rise to 240℃ and 190℃ respectively, and maintains the above temperature for 10 minutes.

[0044] Step 5: Prepare the remelting slag system and bake it.

[0045] The slag system used in electroslag remelting comprises the following components in parts by mass: 5 parts fluorite, 3 parts calcium aluminate, and 2 parts LF refining furnace waste slag. The fluorite contains at least 95% CaF2 and undergoes pre-melting treatment, during which calcium deoxidation is performed. The LF refining furnace waste slag consists of: 52% CaO, 30% Al2O3, 6% MgO, and 12% SiO2. The particle size of the fluorite, calcium aluminate, and refining furnace waste slag is 10-20 mm. After being mixed thoroughly, the mixture is baked at 800℃ for 8 hours.

[0046] Step Six: After heating the crystallizer, turn off the temperature control integrated box, then introduce argon gas into the crystallizer through a stainless steel pipe for 10 minutes. Afterward, connect the cooling water to the bottom water tank of the crystallizer, and continue introducing argon gas. Remove the slag and quickly add it into the crystallizer, ensuring the slag temperature is not lower than 300°C. After 30 minutes of remelting, turn off the argon gas, remove the argon gas pipe, and continue remelting. In this embodiment, the remelted electroslag ingot has virtually no pores at the bottom, and the hydrogen content is less than 2 ppm.

[0047] Example 2

[0048] This embodiment describes a method for preparing low-hydrogen stainless steel electroslag ingots. The preparation apparatus structure is the same as in Embodiment 1, and the specific steps are as follows:

[0049] Step 1: First, peel off the outer layer of the stainless steel consumable electrode.

[0050] Step 2: Use a crane to transport the low-hydrogen stainless steel electroslag ingot preparation device to the designated work station and install the consumable electrode 5 in the crystallizer;

[0051] Step 3: Connect the inlet and outlet of the preparation device to the circuit using a quick-connect device;

[0052] Step 4: The temperature control integrated box controls the first and second channel resistance wires to work, and controls the temperature of the first and second channel resistance wires to rise to 260°C and 220°C respectively, and maintains the above temperature for 15 minutes.

[0053] Step 5: Prepare the remelting slag system and bake it.

[0054] The slag system used in electroslag remelting comprises the following components in parts by mass: 4.5 parts fluorite, 3.5 parts calcium aluminate, and 2 parts LF refining furnace waste slag. The fluorite contains at least 95% CaF2 and undergoes pre-melting treatment, during which calcium deoxidation is performed. The LF refining furnace waste slag consists of: 50% CaO, 35% Al2O3, 5% MgO, and 10% SiO2. The particle size of the fluorite, calcium aluminate, and refining furnace waste slag is 10-20 mm. After being mixed thoroughly, the mixture is baked at 850℃ for 6 hours.

[0055] Step Six: After heating the crystallizer, turn off the temperature control integrated box, then introduce argon gas into the crystallizer through a stainless steel pipe for 8 minutes. After that, connect the cooling water in the bottom water tank of the crystallizer, and continue to introduce argon gas. Quickly add the slag material into the crystallizer, ensuring the temperature of the slag material added to the crystallizer is not lower than 300°C. After 30 minutes of remelting, turn off the argon gas, remove the argon gas pipe, and continue remelting. In this embodiment, the electroslag ingot obtained by remelting has virtually no pores at the bottom, and the hydrogen content is less than 2 ppm.

[0056] Example 3

[0057] This embodiment describes a method for preparing low-hydrogen stainless steel electroslag ingots. The preparation apparatus structure is the same as in Embodiment 1, and the specific steps are as follows:

[0058] Step 1: First, peel off the outer layer of the stainless steel consumable electrode.

[0059] Step 2: Use a crane to transport the low-hydrogen stainless steel electroslag ingot preparation device to the designated work station and install the consumable electrode 5 in the crystallizer;

[0060] Step 3: Connect the inlet and outlet of the preparation device to the circuit using a quick-connect device;

[0061] Step 4: The temperature control integrated box controls the first and second channel resistance wires to work, and controls the temperature of the first and second channel resistance wires to rise to 255°C and 205°C respectively, and maintains the above temperature for 13 minutes.

[0062] Step 5: Prepare the remelting slag system and bake it.

[0063] The slag system used in electroslag remelting comprises the following components in parts by mass: 4 parts fluorite, 4 parts calcium aluminate, and 3 parts LF refining furnace waste slag. The fluorite contains at least 95% CaF2 and undergoes pre-melting treatment, during which calcium deoxidation is performed. The LF refining furnace waste slag consists of: 60% CaO, 28% Al2O3, 4% MgO, and 8% SiO2. The particle size of the fluorite, calcium aluminate, and refining furnace waste slag is 10-20 mm. After being mixed thoroughly, the mixture is baked at 820℃ for 7 hours.

[0064] Step Six: After heating the crystallizer, turn off the temperature control integrated box, then introduce argon gas into the crystallizer through a stainless steel pipe for 12 minutes. After that, connect the cooling water in the bottom water tank of the crystallizer, and continue to introduce argon gas. Quickly remove the slag and add it into the crystallizer. The temperature of the slag added to the crystallizer should not be lower than 300°C. After 30 minutes of remelting, turn off the argon gas, remove the argon gas pipe, and continue remelting. In this embodiment, the electroslag ingot obtained by remelting has virtually no pores at the bottom, and the hydrogen content is less than 2 ppm.

[0065] In conjunction with Examples 1-3, the electroslag remelting apparatus and method of the present invention can simultaneously achieve heating of the consumable electrode, the arc-starting plate, and the crystallizer, as well as removal of condensate from the surfaces of the three components. This reduces the moisture content of the electroslag remelting system, thereby effectively reducing the porosity and hydrogen content of the electroslag ingot, and ensuring that the hydrogen content is stably controlled at ≤2ppm.

Claims

1. An apparatus for preparing low-hydrogen stainless steel electroslag ingots, comprising a crystallizer (1), characterized in that: The lower part of the crystallizer (1) is provided with a heating chamber (9) that surrounds the water gap (13) in the circumferential direction. The heating chamber (9) is a non-connected annular structure and is provided with a dual-channel heating resistance wire (11) for heating the arc-starting plate (4), the self-consuming electrode (5) and the inner wall of the crystallizer. The dual-channel heating resistance wire (11) includes a first channel (11-1) and a second channel (11-2). Both the first channel (11-1) and the second channel (11-2) are formed by connecting the ends of parallel arc-shaped resistance wires. The first channel (11-1) is located above the second channel (11-2), and the bottom end of the first channel (11-1) and the top end of the second channel (11-2) are both connected to the third terminal (11-5). The resistance value of the resistance wire in the first channel (11-1) is greater than the resistance value of the resistance wire in the second channel (11-2). The heating chamber (9) is provided with an annular support plate (12). The outer walls of the annular support plate (12) are provided with locking ribs (14) that engage with the heating chamber (9). The inner wall is machined with a spiral groove (1201) that matches the dual-channel heating resistance wire (11). The dual-channel heating resistance wire (11) is installed in the spiral groove (1201). The heating chamber (9) has an annular copper plate on one side near the water gap (13). The annular support plate (12) is made of insulating material, and the bottom end of the spiral groove (1201) is inclined, with an angle of 20°~30° between it and the side wall of the annular copper plate.

2. The apparatus for preparing low-hydrogen stainless steel electroslag ingots according to claim 1, characterized in that: The crystallizer (1) has a detection chamber (15) inside, and the height of the detection chamber is located in the middle of the heating chamber (9). The temperature sensor (8) is installed in the detection chamber and one end is in contact with the inner wall of the crystallizer for measuring the heating temperature of the crystallizer. The other end of the temperature sensor (8) and the dual-channel heating resistance wire (11) are connected to the temperature control integrated box (16). The bottom of the crystallizer (1) is machined with an annular groove, and an annular flange (6) is installed in the annular groove for sealing the heating chamber (9). The height of the heating chamber (9) is one-third of the total height of the crystallizer, and the width of the water slit (13) inside it is 2~3mm and has a structure that is wider at the top and narrower at the bottom.

3. A method for preparing low-hydrogen stainless steel electroslag ingots, characterized in that: Using the preparation apparatus described in claim 1 or 2, before electroslag remelting begins, the device is first heated by a dual-channel heating resistance wire (11); specifically, the temperatures of the first-channel resistance wire and the second-channel resistance wire are controlled to rise to 240°C~260°C and 190°C~220°C respectively, and the above temperatures are maintained for 10~15 minutes.

4. The method for preparing a low-hydrogen stainless steel electroslag ingot according to claim 3, characterized in that: The slag system used in electroslag remelting includes the following components in parts by mass: 4-5 parts fluorite, 3-4 parts calcium aluminate, and 2-3 parts LF refining furnace waste slag.

5. The method for preparing a low-hydrogen stainless steel electroslag ingot according to claim 4, characterized in that, The fluorite contains 95% or more CaF2 and undergoes pre-melting treatment, during which calcium deoxidation is performed. The composition of the LF refining furnace slag is: CaO 50-60%; Al2O3 28-35%; MgO 4-6%; SiO2 8-12%.

6. The method for preparing a low-hydrogen stainless steel electroslag ingot according to claim 5, characterized in that, Before electroslag remelting begins, the temperatures of the first and second resistance wires are raised to 240°C~260°C and 190°C~220°C respectively, and maintained at these temperatures for 10~15 minutes. The particle size of the fluorite, calcium aluminate, and refining furnace slag is 10~20mm. After mixing them, they are baked at 800~850°C for 6~8 hours, and the temperature of the slag material added to the crystallizer is not lower than 300°C.

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