An electroslag remelting starting device and starting method

Abstract

The present application relates to the technical fields of metallurgical manufacturing, in particular to an electric-shock remelting starting device and a starting method, the starting device is combined with the electrode by using a round plate starting plate with the same material and diameter as the electrode, and the heat generated by the arc between the electrode and the starting plate is used to realize the melting of the slag and the starting of the arc, the bottom pad is not easily deformed by heat after being heated by using the combination of the center plate and the outer ring to support the starting plate, so that the stable starting distance between the electrode and the starting plate can be maintained to realize the smooth starting of the arc, at the same time, the starting plate is lifted by the center plate support pad, and the electrode current is smoothly guided to the crystallizer bottom water tank, which is beneficial to improve the success rate of starting the arc; the starting method uses the above starting device, and by accurately controlling the distance between the electrode and the starting plate during the starting process, the success rate of the arc starting can be improved, the electric-shock remelting starting with no medium, high efficiency, high quality, low cost and green can be realized, and the purity of the steel ingot is improved.

Description

Technical Field

[0001] This invention relates to the field of metallurgical manufacturing technology, specifically to an electroslag remelting start-up device and start-up method. Background Technology

[0002] In the current electroslag remelting process, it is generally necessary to fill the starting medium (i.e., arc igniter) between the starting plate and the consumable electrode to achieve ignition and arc initiation. The industry mainstream uses two types of arc igniters: solid slag and steel scrap of the same material. However, both of them have significant technical defects and process drawbacks in practical applications, which have become key issues restricting the improvement of the quality of electroslag remelted steel ingots and the green production.

[0003] When solid slag is used as an arc igniter, existing formulations are mostly compounded to meet arc ignition requirements, and functional components such as fluorite (calcium fluoride), titanium compounds, and carbon powder are commonly added. During the start-up stage of electroslag remelting, this type of solid slag is heated and melted, and participates in the arc ignition process. Its own exogenous components will directly introduce non-metallic inclusions, harmful elements and other impurities, which will significantly reduce the purity of steel ingots and make it difficult to meet the stringent requirements of high-end special steel for material purity.

[0004] When steel chips are used as arc igniters, to ensure the uniformity of the steel ingot material, steel chips that are completely homogeneous with the consumable electrode must be selected. Their preparation is highly dependent on mechanical cutting, resulting in high raw material losses and complicated processing procedures, leading to high production costs for arc igniters. More importantly, during the machining process, steel chips are easily contaminated with cutting fluid, lubricating oil, and other oily impurities. This not only significantly reduces the stability and success rate of electroslag arc ignition but also easily causes faults such as arc breakage and arc deviation. Furthermore, such contaminated steel chips cannot be used directly and require additional secondary purification treatment such as degreasing and drying. This not only extends the production cycle and increases process energy consumption but also generates waste liquid and waste gas during the secondary treatment process, which can easily cause environmental pollution. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems existing in the prior art where the electroslag remelting start-up process generally uses solid slag, steel scrap and other arc-initiating agents for ignition and arc initiation, which has high arc initiation costs, affects the purity of steel ingots and easily causes pollution to the production environment. The invention provides an electroslag remelting start-up device and start-up method.

[0006] An electroslag remelting start-up device includes:

[0007] A crystallizer, wherein a bottom water tank is provided at the bottom of the crystallizer; A bottom pad is fixedly installed on the top surface of the bottom water tank. The bottom pad includes a central plate and an outer ring. The central plate and the outer ring are coaxially fitted together with a clearance fit. Electrode, the electrode comprising a cylindrical component; A starter plate, the starter plate comprising a circular plate component, the starter plate being coaxially welded to the center plate; The thickness of the center plate is greater than the thickness of the outer ring, the diameter of the starting plate is less than the diameter of the center plate, the starting plate and the electrode are made of the same material and have the same diameter, and the ratio of the diameter of the electrode to the average diameter of the crystallizer is 0.75~0.82.

[0008] This invention discloses an electroslag remelting start-up device. It combines a circular start-up plate of the same material and diameter as the electrode with the electrode. The arc is initiated by the heat generated from the arc between the electrode and the start-up plate, melting the slag and initiating the arc. The arc initiation process does not involve an arc-initiating agent that affects the purity of the steel ingot, thus reducing arc initiation costs and improving ingot purity. The start-up plate is supported by a base pad formed by a combination of a central plate and an outer ring. This base pad is less prone to thermal deformation after arc initiation heating, maintaining a stable arc initiation distance with the electrode and facilitating smooth arc initiation. Furthermore, by setting the thickness of the central plate to be greater than that of the outer ring and limiting the electrode size, the central plate supports and elevates the start-up plate. This allows the electrode current to be smoothly guided to the bottom water tank of the crystallizer via the slightly elevated central plate, improving the arc initiation success rate and ensuring a suitable electrode melting speed and safe distance during subsequent remelting, thereby guaranteeing steel ingot quality and production safety. During arc initiation, the bottom water tank is protected by both the central plate and the start-up plate, preventing direct contact between the melting start-up plate and the bottom water tank, thus better protecting the bottom water tank.

[0009] Preferably, the thickness of the starting plate is 30-40mm, the diameter of the starting plate is 18-25mm smaller than the diameter of the center plate, and the thickness of the center plate is 0.8-1.5mm greater than the thickness of the outer ring.

[0010] Preferably, a 45° weld bead area is formed between the starting plate and the center plate, and the height of the weld bead area is ≥ 1 / 2 of the thickness of the starting plate. This ensures that the starting plate can be firmly welded to the center plate, increases conductivity, and maintains a stable arc-starting distance during the arc-starting process.

[0011] Preferably, the starter plate is obtained by cutting the electrode. This ensures that the starter plate and the electrode are made of the same material and reduces manufacturing costs.

[0012] An electroslag remelting start-up method, employing an electroslag remelting start-up device as described above, includes the following steps: S1. Place the electrode coaxially on the start plate inside the crystallizer, keeping 5% to 10% of the electrode's weight on the start plate; S2. Add the first batch of slag material, which is 25% to 35% of the total weight of the slag material, to the circumference of the electrode ring. S3. Within 3 to 60 seconds of energizing, control the arc-starting distance to Δd, where Δd = 0.001D + 0.5, and Δd is the arc-starting distance between the electrode and the starting plate, and D is the average diameter of the crystallizer, both in cm. S4. Within 1-3 minutes of power-on, control the arc-starting distance to 10-15mm; S5. Within 3-5 minutes of power-on, control the arc-starting distance to 15-20mm; S6. Within 5 to 10 minutes of power-on, control the arc-starting distance to 20 to 25 mm; S7. Add the remaining slag, switch to automatic control, and complete the arc initiation process.

[0013] The present invention discloses an electroslag remelting start-up method that, by employing an electroslag remelting start-up device with a specific structure, can improve the arc ignition success rate and the purity of steel ingots. At the same time, during the start-up process, by precisely controlling the distance between the electrode and the start-up plate, it can prevent arc extinguishing due to excessive distance or adhesion due to excessive distance, thereby improving the arc starting success rate and achieving a medium-free, efficient, high-quality, low-cost, and green electroslag remelting start-up.

[0014] Preferably, in step S2, the total weight W of the slag material satisfies: W = 0.05~0.06D 2 kg, where D is the average diameter of the crystallizer in cm. Accurate calculation of the total slag weight provides a basis for slag addition during remelting startup, ensuring a smooth start-up.

[0015] Preferably, in step S3, the starting voltage U satisfies: U = 0.21D + 35~40V, where D is the average diameter of the crystallizer in cm, and the starting slag resistance is 3mΩ~3.5mΩ.

[0016] Preferably, step S2 further includes: before power-on startup, continuously filling the crystallizer with a startup atmosphere for gas replacement, the startup atmosphere comprising a mixture of argon and nitrogen. This ensures that during startup, there is no additional arc-initiating medium between the electrode and the startup plate, only a mixture of argon and nitrogen. The mixed gas increases the arc length, which is beneficial for further increasing the arc-initiating success rate.

[0017] Preferably, gas replacement includes replacing the air inside the crystallizer with a mixed gas, and the flow rate is 250~300 m³ / h. 3 / h, time ≥50min, oxygen concentration in the crystallizer after replacement ≤0.5PPm.

[0018] Preferably, the starting atmosphere comprises argon with a volume fraction of 70% to 97% and nitrogen with a volume fraction of 3% to 30%.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides an electroslag remelting start-up device, which combines a circular plate-shaped start-up plate of the same material and diameter as the electrode with the electrode. The heat generated by the arc between the electrode and the start-up plate is used to melt the slag and start the arc. The arc-starting process does not have an arc-starting agent that affects the purity of the steel ingot, which is beneficial to reducing the arc-starting cost and improving the purity of the steel ingot. 2. The present invention provides an electroslag remelting start-up device, which uses a combination of a central plate and an outer ring to form a bottom pad to support the start-up plate, so that the bottom pad is not easily deformed by heat after arc heating, and can maintain a stable arc starting distance with the electrode, which is conducive to achieving smooth arc starting; 3. This invention provides an electroslag remelting start-up device. By setting the thickness of the center plate to be higher than that of the outer ring and limiting the electrode size, the center plate supports and raises the start-up plate, so that the electrode current can be smoothly guided to the bottom water tank of the crystallizer through the center plate which is slightly higher. This helps to improve the arc ignition success rate and can ensure a suitable electrode melting speed and safe distance in the subsequent remelting process, thereby ensuring the quality of steel ingots and production safety. 4. The present invention provides an electroslag remelting starting device. During the arc ignition process, the bottom water tank is protected by both the center plate and the starting plate. The melting of the starting plate is less likely to directly contact the bottom water tank, thus better protecting the bottom water tank. 5. This invention provides an electroslag remelting start-up method, which, by employing an electroslag remelting start-up device with a specific structure, can improve the arc initiation success rate and the purity of steel ingots; 6. This invention provides an electroslag remelting start-up method. During the start-up process, by precisely controlling the distance between the electrode and the start-up plate, arc extinguishing due to excessively long distance or adhesion due to excessively short distance can be prevented. This can improve the success rate of arc starting and achieve a medium-free, efficient, high-quality, low-cost, and green electroslag remelting start-up. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of an electroslag remelting start-up device according to Example 1.

[0021] Figure 2 for Figure 1 A magnified structural diagram of part A in the middle.

[0022] Marked in the image: 1-Crystallizer, 2-Bottom pad, 21-Center plate, 22-Outer ring, 3-Electrode, 4-Start-up plate, 41-Weld corner area, 5-Bottom water tank, 6-Slag material, 7-Start-up atmosphere. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0024] Unless otherwise specified, the terms "upper," "lower," "left," "right," "center," "inner," and "outer," etc., used in the description of specific embodiments of the present invention to indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is usually placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, and for enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0025] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," "parallel," and "coaxial" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, parallel, or coaxial. Slight tilt or deviation is permissible, as long as it does not affect the normal function of the relevant component. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," not that the structure must be perfectly horizontal; a slight tilt is acceptable. "Coaxial" means that two components are arranged as coaxially as possible, allowing them to move coaxially or approximately coaxially when their relative positions change. Alternatively, it can be simplified to mean that the corresponding device / component / element, when arranged in "horizontal," "vertical," "suspended," "parallel," or "coaxial" directions, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. For example, the deviation in the "coaxial" direction is controlled within 0.2-1mm, preferably within 0.2-0.5mm. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the solution of the present invention.

[0026] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0027] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as two, three, four, five, six, seven, eight, or nine, and can even exceed nine.

[0028] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to connection methods commonly used in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0029] Example 1 like Figures 1-2 As shown, an electroslag remelting start-up device includes a crystallizer 1, a bottom pad 2, an electrode 3, and a start-up plate 4. A bottom water tank 5 is provided at the bottom of the crystallizer 1, and the bottom pad 2 is fixedly provided on the top surface of the bottom water tank 5. The bottom pad 2 includes a central plate 21 and an outer ring 22. The central plate 21 and the outer ring 22 are coaxially embedded and have a clearance fit. The electrode 3 includes a cylindrical part, and the start-up plate 4 includes a circular plate part. The start-up plate 4 is coaxially welded to the central plate 21.

[0030] The crystallizer 1 is the core tooling for electroslag remelting. It is used to contain molten slag for refining, assist in conducting electricity, seal and isolate air to prevent oxidation and leakage of steel and slag, and realize the forming of steel ingots. A bottom water tank 5 is set at the bottom of the crystallizer 1 to assist in establishing a conductive circuit and cooling.

[0031] In this embodiment, the crystallizer 1 is a structural component with a conical inner cavity. The upper diameter of the crystallizer 1 is larger than the lower diameter to facilitate the removal of the steel ingot after it has been formed.

[0032] The bottom pad 2 is a plate-type structural component set on top of the bottom water tank 5 to help stabilize the arc.

[0033] like Figure 1 As shown, in this embodiment, the base pad 2 consists of two parts: a central plate 21 and an outer ring 22. The central plate 21 is a circular plate, and the outer ring 22 is an annular plate. The central plate 21 is embedded in the outer ring 22 with a clearance fit, so that the central plate 21 and the outer ring 22 can together form the base pad 2 to support the upper structure, while maintaining a separate state. Compared with the overall structure of the base pad 2, it is not easily deformed by thermal stress, which is conducive to maintaining a stable gap with the electrode 3, thereby improving the start-up success rate.

[0034] Electrode 3, also known as consumable electrode 3, serves as the power supply and raw material carrier for electroslag remelting. After current is applied, it generates slag resistance heat to melt itself, continuously supplying molten steel to the molten pool, while simultaneously participating in electrical conduction to form a complete smelting circuit.

[0035] The starting plate 4 is an arc-initiating material placed between the bottom pad 2 and the electrode 3. It forms an electric arc by breaking down the air with voltage. The heat generated by the arc between the electrode 3 and the starting plate 4 melts the slag material 6 to establish a liquid slag pool, thus completing the initial start-up of the electroslag furnace.

[0036] In an optional embodiment, the thickness of the center plate 21 is greater than the thickness of the outer ring 22. This makes the center plate 21 higher than the outer ring 22, providing sufficient height to support the starting plate 4 and ensuring that current flows through the electrode 3 to the bottom water tank 5, thus improving the success rate of starting.

[0037] In an optional embodiment, the diameter of the starting plate 4 is less than the diameter of the center plate 21. The starting plate 4 and the electrode 3 are made of the same material and have the same diameter. The ratio of the diameter of the electrode 3 to the average diameter of the crystallizer 1 is 0.75 to 0.82. Maintaining the center plate 21, the starting plate 4, the electrode 3, and the crystallizer 1 in a predetermined relative structural state facilitates the smooth flow of electricity, provides structural support for the electroslag remelting arc initiation process, and promotes successful arc initiation.

[0038] In one or more embodiments, the thickness of the starter plate 4 can be 30~40mm, the diameter of the starter plate 4 can be set to be 18~25mm smaller than the diameter of the center plate 21, and the thickness of the center plate 21 can be set to be 0.8~1.5mm greater than the thickness of the outer ring 22.

[0039] In this embodiment, the thickness of the starter plate 4 can be 35mm, the diameter of the starter plate 4 can be set to be less than the diameter of the center plate 21 by 20mm, and the thickness of the center plate 21 can be set to be greater than the thickness of the outer ring 22 by 1mm.

[0040] In one or more embodiments, a 45° weld bead region 41 is formed between the starting plate 4 and the center plate 21, and the height of the weld bead region 41 is greater than or equal to half the thickness of the starting plate 4. This allows the starting plate 4 to be firmly welded to the center plate 21, increases conductivity, and maintains a stable arc-starting distance during the arc-starting process.

[0041] In an optional embodiment, the starter plate 4 is obtained by cutting the electrode 3. This ensures that the starter plate 4 and the electrode 3 are made of the same material and reduces manufacturing costs.

[0042] This embodiment of an electroslag remelting start-up device uses a circular plate-shaped start-up plate 4 of the same material and diameter as the electrode 3, combined with the electrode 3. The heat generated by the arc between the electrode 3 and the start-up plate 4 melts the slag material 6 and initiates the arc. The arc initiation process does not involve an arc-initiating agent that affects the purity of the steel ingot, which helps to reduce the arc initiation cost and improve the purity of the steel ingot. The start-up plate 4 is supported by a base pad 2 formed by a combination of a central plate 21 and an outer ring 22. This base pad 2 is not easily deformed by heat after arc initiation heating and can maintain a stable arc initiation distance with the electrode 3, which is conducive to successful arc initiation. At the same time, by setting the thickness of the central plate 21 to be higher than the thickness of the outer ring 22 and limiting the size of the electrode 3, the central plate 21 supports and raises the start-up plate 4. The current of the electrode 3 is smoothly guided to the bottom water tank 5 of the crystallizer 1 through the slightly higher central plate 21, which helps to improve the start-up success rate. Compared with the dispersed start-up blocks, it can not only smoothly guide the current to the bottom water tank 5, but also protect the bottom water tank 5, making the bottom water tank 5 less susceptible to the influence of the melting of the start-up plate 4.

[0043] Example 2 An electroslag remelting start-up method, employing an electroslag remelting start-up device as described in Example 1, includes the following steps: S1. Place electrode 3 coaxially on the start plate 4 inside crystallizer 1, and keep 10% to 50% of the weight of electrode 3 on the start plate 4.

[0044] S1 is the process of placing electrode 3 into crystallizer 1 by touching the bottom. By keeping electrode 3 in contact with starter plate 4 and controlling part of the weight to bear pressure on starter plate 4, preparation is made for arc control. This can completely eliminate the possibility of slag material 6 between electrode 3 and starter plate 4, thereby improving the success rate of arc initiation.

[0045] In an optional embodiment, the surface of electrode 3 is machined and oil stains are removed, and the bottom surface is flat. The surface of the starting plate 4 is machined to be smooth and flat. After electrode 3 is placed in crystallizer 1, a sealed atmosphere protection cover is covered and electrode 3 is placed on the starting plate 4 with its bottom touching the ground. After pressure adjustment, a stable arc starting gap is formed.

[0046] S2. Add the first batch of slag material 6, which is 25% to 35% of the total weight of slag material 6, around the electrode 3.

[0047] S2 is the addition of the first batch of slag material 6 before energization. The first batch of slag material 6 is evenly distributed around the electrode 3. The weight of the first batch of slag material 6 is determined according to the total weight W of the slag material 6.

[0048] In an optional implementation, the total weight W of the slag 6 satisfies: W = 0.05~0.06D²kg, where D is the average diameter of the crystallizer 1 in cm. Accurate calculation of the total weight of the slag 6 provides a basis for adding slag 6 during remelting startup, ensuring a smooth start-up.

[0049] In this embodiment, when the average diameter of the crystallizer 1 is greater than 160cm, the upper limit of the calculation range is selected for the total weight of the slag 6, and vice versa. For example, when the average diameter of the crystallizer 1 is 185cm, the calculation range of the total weight of the slag 6 is 1711kg~2053kg, and the total weight of the slag 6 is finally determined to be 2053kg.

[0050] In an optional embodiment, the average diameter of the crystallizer 1 is determined based on the calculation of the upper and lower diameters of the crystallizer 1.

[0051] In one or more embodiments, step S2 further includes: after the first batch of slag material 6 is added, continuously filling the crystallizer 1 with a starting atmosphere 7 for gas replacement, the starting atmosphere 7 comprising a mixture of argon and nitrogen. This ensures that during the starting process, there is no additional arc-initiating medium between the electrode 3 and the starting plate 4, only a mixture of argon and nitrogen. The increased arc length due to the mixed gas further enhances the arc-initiating success rate.

[0052] In an optional embodiment, gas replacement includes replacing the air in the crystallizer 1 with a mixed gas, and the following conditions are met: flow rate 250~300m3 / h, time ≥50min, and oxygen concentration in the crystallizer 1 after replacement ≤0.5ppm.

[0053] In an optional implementation, the starting atmosphere 7 can be argon with a volume fraction of 70% to 97% and nitrogen with a volume fraction of 3% to 30%.

[0054] In an optional embodiment, the start-up atmosphere 7 is connected to an external gas supply device via an interface on the atmosphere protection cover of the crystallizer 1 for gas replacement.

[0055] S3. Within 3 to 60 seconds of energizing, control the arc-starting distance to Δd, where Δd = 0.001D + 0.5, and Δd is the arc-starting distance between electrode 3 and starting plate 4, and D is the average diameter of crystallizer 1, both in cm.

[0056] S4. Within 1-3 minutes of power-on, control the arc-starting distance to 10-15mm.

[0057] S5. Within 3-5 minutes of power-on, control the arc starting distance to 15-20mm.

[0058] S6. Within 5-10 minutes of power-on, control the arc-starting distance to 20-25mm.

[0059] S7. Add the remaining slag material 6, switch to automatic control, and complete the arc initiation process.

[0060] During the process from S3 to S6, the slag material 6 is gradually melted by gradually increasing the height of electrode 3, and the arcing is continuously maintained by precisely controlling the height of electrode 3.

[0061] In an optional implementation, in step S3, the starting voltage U satisfies: U = 0.21D + 35~40V, where D is the average diameter of crystallizer 1 in cm, and the starting slag resistance is 3mΩ~3.5mΩ.

[0062] This embodiment of an electroslag remelting start-up method, by employing an electroslag remelting start-up device with a specific structure, can improve the arc ignition success rate and the purity of steel ingots. At the same time, during the start-up process, by precisely controlling the distance between the electrode 3 and the start-up plate 4, it can prevent arc extinguishing due to excessive distance or adhesion due to excessive distance, thereby improving the arc starting success rate and achieving a medium-free, efficient, high-quality, low-cost, and green electroslag remelting start-up.

[0063] This embodiment of an electroslag remelting start-up method produces high-quality steel ingots with stable carbon and other components and low inclusion content, achieving grades of 0.0 for Class A coarse series, 0.0 for fine series, 0.0 for Class B coarse series, 0.0 for fine series, 0.0 for Class C coarse series, 0.0 for fine series, 0.0 for Class D coarse series, 0.5 for fine series, and 0.5 for Class DS. During the start-up process, no arc-initiating agent containing calcium fluoride or similar materials is used, resulting in no fluoride emissions, making it green and environmentally friendly, and achieving a 100% arc-initiating success rate.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An electroslag remelting start-up device, characterized in that, include: Crystallizer (1), with a bottom water tank (5) provided at the bottom of the crystallizer (1); Bottom pad (2), the bottom pad (2) is fixedly installed on the top surface of the bottom water tank (5), the bottom pad (2) includes a center plate (21) and an outer ring (22), the center plate (21) and the outer ring (22) are coaxially fitted and clearance fit; Electrode (3), the electrode (3) comprising a cylindrical component; A starter plate (4) is provided, comprising a circular plate component, which is coaxially welded to the center plate (21). The thickness of the center plate (21) is greater than the thickness of the outer ring (22), the diameter of the starting plate (4) is less than the diameter of the center plate (21), the starting plate (4) and the electrode (3) are made of the same material and have the same diameter, and the diameter of the electrode (3) / the average diameter of the crystallizer (1) is 0.75~0.

82.

2. The electroslag remelting start-up device according to claim 1, characterized in that, The starting plate (4) has a thickness of 30~40mm, the diameter of the starting plate (4) is 18~25mm smaller than the diameter of the center plate (21), and the thickness of the center plate (21) is 0.8~1.5mm greater than the thickness of the outer ring (22).

3. The electroslag remelting start-up device according to claim 2, characterized in that, A 45° welding angle region (41) is formed between the starting plate (4) and the center plate (21), and the height of the welding angle region (41) is ≥ 1 / 2 of the thickness of the starting plate (4).

4. The electroslag remelting start-up device according to claim 1, characterized in that, The starter plate (4) is obtained by cutting the electrode (3).

5. A method for starting up an electroslag remelting process, characterized in that, The electroslag remelting start-up device as described in any one of claims 1-4 is adopted, and includes the following steps: S1. Place the electrode (3) coaxially on the start plate (4) inside the crystallizer (1), and keep 5%~10% of the weight of the electrode (3) on the start plate (4); S2. Add the first batch of slag material (6) with a total weight of 25%~35% to the circumference of the electrode (3); S3. Within 3 to 60 seconds of power-on, control the arc-starting distance to △d, △d = 0.001D + 0.5, where: △d is the arc-starting distance between electrode (3) and starting plate (4), and D is the average diameter of crystallizer (1), both in cm; S4. Within 1-3 minutes of power-on, control the arc-starting distance to 10-15mm; S5. Within 3-5 minutes of power-on, control the arc-starting distance to 15-20mm; S6. Within 5-10 minutes of power-on, control the arc-starting distance to 20-25mm; S7. Add the remaining slag (6), switch to automatic control, and complete the arc starting process.

6. The electroslag remelting start-up method according to claim 5, characterized in that, In step S2, the total weight W of the slag (6) satisfies: W = 0.05~0.06D2kg, where D is the average diameter of the crystallizer (1) in cm.

7. The electroslag remelting start-up method according to claim 5, characterized in that, In step S3, the starting voltage U satisfies: U=0.21D+35~40V, where D is the average diameter of the crystallizer (1) in cm, and the starting slag resistance is 3mΩ~3.5mΩ.

8. The electroslag remelting start-up method according to claim 5, characterized in that, Step S2 further includes: before powering on, continuously filling the crystallizer (1) with a starting atmosphere (7) for gas replacement, the starting atmosphere (7) including a mixture of argon and nitrogen.

9. The electroslag remelting start-up method according to claim 8, characterized in that, Gas replacement includes replacing the air in the crystallizer (1) with a mixed gas, and the following conditions must be met: flow rate 250~300m3 / h, time ≥50min, and oxygen concentration in the crystallizer (1) after replacement ≤0.5PPm.

10. The electroslag remelting start-up method according to claim 8, characterized in that, The starting atmosphere (7) consists of argon with a volume fraction of 70% to 97% and nitrogen with a volume fraction of 3% to 30%.

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