Steelmaking closed-loop arc sealing device

Abstract

The utility model discloses a steelmaking closed-loop arc sealing device, which is used for an electric arc furnace and an LF (ladle furnace) refining furnace, realizes arc sealing operation by utilizing arc sealing particles, and comprises a small furnace cover body and a graphite electrode hole, and the electrode hole is formed in the vertical direction of the small furnace cover body in a penetrating manner; a material distribution mechanism is embedded in the lower portion of the small furnace cover body and comprises an annular pipe, a feeding pipe and an air inlet pipe which are embedded in the lower portion of the small furnace cover body. The arc sealing particles can be conveyed to the central area in the hearth through the arranged material distribution mechanism, and the particles fall into a molten pool along a circular seam under the blowing action of compressed air in the conveying process. Therefore, a plurality of particles can form a cylindrical semi-closed curtain, and meanwhile, the particles fall into the molten pool to participate in the reaction to form a foam slag curtain and an air curtain. And under the combined action, the electric arc is effectively sealed and controlled in the central area in the furnace. The arc sealing method can realize the maximization of multiple metallurgical effects.

Description

Technical Field

[0001] The utility model belongs to the technical field of electric arc furnace and LF refining furnace smelting, and specifically relates to a steelmaking closed-loop arc sealing device. Background Art

[0002] The foam slag operation of electric arc furnace and LF refining furnace has played a role in alleviating the problems of unstable long arc energy conversion and reduced input power into the furnace. Specifically, by adopting the foam slag operation, the heating rate of molten steel is significantly improved, so that the amount of scrap steel added can be greatly increased, effectively increasing steel production and reducing the consumption of steel materials. At the same time, the foam slag operation can reduce the high-temperature radiation damage of the long arc to the furnace lining and ladle lining, reduce the consumption of refractory materials of the furnace lining and ladle lining, extend the service life of the furnace lining and ladle lining, and reduce the generation of foreign inclusions brought into the molten steel due to the erosion of the ladle lining, thereby improving the purity of the molten steel.

[0003] However, in the current electric arc furnace and LF refining furnace, only the middle stage of slag foaming is good during the smelting of a batch of steel. This is because the lime slag process is required in the early stage, and the slag becomes thinner due to the increase in furnace temperature in the later stage, resulting in poor slag foaming effect in the early and late stages. The arc is also not efficiently sealed during the entire smelting process.

[0004] In summary, the utility model provides a steelmaking closed-loop arc sealing device to solve the above problems. Utility Model Content

[0005] In view of the deficiencies in the prior art, the utility model aims to provide a steelmaking closed-loop arc sealing device to achieve arc sealing operation in the smelting process of an electric arc furnace and a LF refining furnace.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A steelmaking closed-loop arc sealing device, used in an electric arc furnace and a LF refining furnace and realizing arc sealing operation by using arc sealing particles, comprises: a small furnace cover body, an electrode hole for placing an electrode, the electrode hole being penetrated and opened in the vertical direction of the furnace cover body;

[0008] A material distribution mechanism is embedded in the interior below the small furnace cover body, and the material distribution mechanism includes a ring pipe, a feed pipe and an air intake pipe embedded in the bottom of the furnace cover body, and the three are integrated. One end of the feed pipe and the air intake pipe is connected to the ring pipe, and the other ends of the feed pipe and the air intake pipe pass through the top of the small furnace cover body, and the openings of the feed pipe and the air intake pipe face upwards. The ring pipe is provided with a ring slit on one side facing the bottom of the small furnace cover body for arc sealing particles to fall;

[0009] The annular gap is arranged so that arc-sealing particles can fall from the annular tube into the furnace;

[0010] The air inlet pipe is used to transmit compressed gas, so that arc-sealing particles flow in the annular pipe, and the arc-sealing particles fall into the molten pool from the circumference of the annular seam.

[0011] The utility model is further configured as follows: the plurality of electrode holes are all located within the circumference of the annular tube, the annular seam of the annular tube is exposed on the arched surface at the lower end of the small furnace cover body, the width of the annular seam is 15-30 mm, and the distance between the annular tube and the inner wall of the electrode hole is 70-120 mm.

[0012] The utility model is further configured as follows: the upper half of the conventional small furnace cover body is in the shape of a truncated cone, and the lower half of the furnace cover body is in the shape of an inverted frustum.

[0013] The utility model is further configured as follows: the number of the electrode holes opened on the furnace cover body is greater than or equal to one.

[0014] The utility model is further configured such that: the angle between the feed pipe and the ring pipe is greater than or equal to 60°, so as to facilitate the conveying of arc-sealing particles.

[0015] In summary, the beneficial technical effects of the utility model are:

[0016] The arc-sealing particles can be transported to the center of the furnace through the feeding mechanism. During the transportation process, the particles are blown by compressed air to fall into the molten pool along the annular gap. Many particles will form a cylindrical semi-enclosed curtain, as well as a foam slag curtain and a gas curtain. They work together to effectively seal the arc in the center of the furnace. This arc-sealing method can maximize multiple metallurgical effects.

[0017] The specific implementation of the utility model is further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described below are only some embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0019] Figure 1 This is one of the three-dimensional schematic diagrams of the combination of the small furnace cover body and the material distribution mechanism of one embodiment of the utility model;

[0020] Figure 2 This is the second three-dimensional schematic diagram of the combination of the small furnace cover body and the material distribution mechanism of one embodiment of the utility model;

[0021] Figure 3 This is one of the exploded three-dimensional schematic diagrams of the small furnace cover body and the material distribution mechanism of one embodiment of the utility model;

[0022] Figure 4 This is the second exploded three-dimensional schematic diagram of the small furnace cover body and the material distribution mechanism of one embodiment of the utility model;

[0023] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0024] 1. Small furnace cover body; 2. Electrode hole; 3. Material distribution mechanism; 4. Ring pipe; 5. Feed pipe; 6. Air inlet pipe; 7. Ring seam; 8. Lifting ear. DETAILED DESCRIPTION

[0025] The utility model is further described in detail below in conjunction with the accompanying drawings.

[0026] Reference Figure 1-4 , a steelmaking closed-loop arc sealing device disclosed in the utility model, which is used for electric arc furnaces and LF refining furnaces and uses arc sealing particles to achieve arc sealing operations, including: a small furnace cover body 1, an electrode hole 2 for placing electrodes, the electrode hole 2 is opened in the vertical direction of the furnace cover body 1; the upper half of the small furnace cover body 1 is a truncated cone, and the lower half of the furnace cover body 1 is an inverted frustum. By using arc sealing particles, arc sealing operations can be effectively performed, energy consumption and environmental pollution can be reduced, air can be inhibited from entering the central ionization area, and steel liquid aspiration can be reduced. The particle size of the arc sealing particles is 2mm to 20mm.

[0027] A distribution mechanism 3 is pre-buried inside the small furnace cover body 1, and the distribution mechanism 3 includes a ring tube 4, a feed pipe 5 and an air intake pipe 6 pre-buried below the small furnace cover body 1, and one end of the feed pipe 5 and the air intake pipe 6 are connected to the ring tube 4, and the other ends of the feed pipe 5 and the air intake pipe 6 pass through the top of the small furnace cover body 1, and the openings of the feed pipe 5 and the air intake pipe 6 face upward, and the ring tube 4 is provided with an annular seam 7 for arc-sealing particles to fall on the side facing the bottom of the small furnace cover body 1; the distribution mechanism 3 below the small furnace cover includes the ring tube 4, the feed pipe 5 and the air intake pipe 6, and their structural design is conducive to the falling of arc-sealing particles, and ensures that the particles are evenly distributed in the central area of ​​the furnace, thereby improving the arc-sealing effect.

[0028] The setting of the annular gap 7 enables arc-sealing particles to fall from the annular tube 4 into the furnace;

[0029] The air inlet pipe 6 is used to transmit compressed gas, so that arc-sealing particles flow in the annular pipe 4 and fall from the annular gap 7 .

[0030] The plurality of electrode holes 2 of the present embodiment are all located within the circumference of the annular tube 4, the annular seam 7 of the annular tube 4 is exposed on the lower end arch surface of the small furnace cover body 1, the width of the annular seam 7 is 15-30 mm, and the distance between the annular tube 4 and the inner wall of the electrode hole 2 is 70-120 mm.

[0031] In this embodiment, the number of the electrode holes 2 opened on the furnace cover body 1 is greater than or equal to one.

[0032] The angle between the feed pipe 5 and the ring pipe 4 of this embodiment is greater than or equal to 60°. A sufficiently large angle can ensure that the flow of the fluid in the pipeline is more stable, reduce the flow resistance, and improve the transmission efficiency of the system.

[0033] By conveying arc-sealing particles into the annular tube 4 and cooperating with the compressed air transmitted by the air inlet pipe 6, the arc-sealing particles flow evenly in the annular tube 4 and fall into the furnace. This can achieve the following comprehensive performance improvements:

[0034] 1. The thickness of foam slag increases by 40-60%, the slag forming speed is faster, and the steelmaking process is more efficient;

[0035] 2. The smelting time is shortened by 5-10%, greatly improving production efficiency;

[0036] 3. Save 3-5% of electricity consumption and reduce energy consumption costs;

[0037] 4. Electrode consumption is reduced by 10-15%, extending electrode life;

[0038] 5. The sound absorption and noise reduction effect increases by 20-30%, improving the working environment;

[0039] 6. Hydrogen absorption is reduced by 70-80%, reducing the hydrogen embrittlement problem of steel;

[0040] 7. Reduce nitrogen absorption by 80-90%, improving the mechanical properties of steel;

[0041] 8. Increase the amount of scrap steel added by 5-20% to improve resource utilization;

[0042] 9. The furnace life and ladle life are increased by 50-70%, reducing the frequency of furnace life and ladle lining replacement;

[0043] 10. Reduce carbon emissions by 10-20%, reducing environmental pollution.

[0044] The present application transports arc-sealing particles into a pre-buried ring around the small furnace cover. The particles are blown by compressed air and fall into the molten pool along the annular seam 7 to form a particle curtain, a foam slag curtain, and a gas curtain, thereby sealing the arc in the central area of ​​the furnace, thereby achieving an electrometallurgical technology that maximizes comprehensive metallurgical effects such as less slag, reduced consumption, reduced noise, nitrogen control, gas control, and increased furnace life and package life.

[0045] The arc-sealing particles in the present application are mainly divided into micro-carbon type and carbon-free type.

[0046] The target ratio of micro carbon type is:

[0047] Free carbon C<1%, CaO 7%, SiO2 20%, MgO 28%, AI2O3 9%, P<0.05%, S<0.1%, expansion arc agent 35%.

[0048] The target ratio of carbon-free type is:

[0049] Free carbon C 0%, CaO 5%, SiO2 23%, MgO 27%, AI2O3 10%, P < 0.05%, S < 0.1%, expansion arc agent 35%.

[0050] The embodiments of this specific implementation method are all preferred embodiments of the utility model, and are not intended to limit the protection scope of the utility model. Therefore, all equivalent changes made based on the shape and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A steelmaking closed-loop arc sealing device, used in electric arc furnaces and LF refining furnaces and utilizing arc sealing particles to achieve arc sealing operation, the characteristics of which include: A small furnace cover body (1) and an electrode hole (2) for placing an electrode, wherein the electrode hole (2) is provided through the small furnace cover body (1) in a vertical direction; A material distribution mechanism (3) is pre-buried inside the lower part of the small furnace cover body (1), and the material distribution mechanism (3) comprises an annular tube (4), a feed pipe (5) and an air intake pipe (6) pre-buried below the small furnace cover body (1); one end of the feed pipe (5) and the air intake pipe (6) are connected to the annular tube (4); the other ends of the feed pipe (5) and the air intake pipe (6) pass through the upper part of the small furnace cover body (1), and the openings of the feed pipe (5) and the air intake pipe (6) face upward; and an annular slit (7) for arc-sealing particles to fall is provided on one side of the annular tube (4) facing the lower part of the small furnace cover body (1); The annular gap (7) is arranged so that arc-sealing particles can enter the furnace from the annular tube (4); The air inlet pipe (6) is used to transmit compressed gas, so that arc-sealing particles flow in the annular pipe (4), and the arc-sealing particles fall into the molten pool from the circumference of the annular gap (7).

2. A steelmaking closed-loop arc sealing device according to claim 1, characterized in that: The plurality of electrode holes (2) are all located in the space of the annular tube (4); the annular seam (7) of the annular tube (4) is exposed on the lower end arch surface of the small furnace cover body (1); the width of the annular seam (7) is 15-30 mm; and the distance between the annular tube (4) and the inner wall of the electrode hole (2) is 70-120 mm.

3. A steelmaking closed-loop arc sealing device according to claim 1, characterized in that: The upper part of the small furnace cover body (1) is in the shape of a truncated cone, and the lower part of the small furnace cover body (1) is in the shape of an inverted frustum.

4. A steelmaking closed-loop arc sealing device according to claim 1, characterized in that: The number of the electrode holes (2) provided on the small furnace cover body (1) is greater than or equal to one.

5. A steelmaking closed-loop arc sealing device according to claim 1, characterized in that: The angle between the feed pipe (5) and the ring pipe (4) is greater than or equal to 60°, so that the arc-sealing particles can be efficiently transported.

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