Efficient steel ladle for alloy smelting

Abstract

The invention provides an efficient steel ladle for alloy smelting. The efficient steel ladle comprises a steel ladle body, a ladle bottom argon blowing mechanism and a sealing ladle cover mechanism. The steel ladle body sequentially comprises a steel ladle shell, a nanometer aerogel heat insulation layer, a heat preservation layer and a fire-resistant working layer from outside to inside. The ladle bottom argon blowing mechanism comprises a rotating seat, a driving motor and a multi-stage gradient air brick, bubbles are uniformly refined, the molten steel refining efficiency is improved, the anti-blocking capacity of the air brick is enhanced, and a gradient structure can disperse thermal stress and prolong the service life of the air brick; the sealing ladle cover mechanism comprises an arc-shaped ladle cover and a ceramic fiber sealing gasket, the arc-shaped ladle cover and the ceramic fiber sealing gasket cooperate with a heat preservation structure of the steel ladle body, a multi-layer composite heat insulation structure is integrally formed, uncovering temperature drop is reduced, the ceramic fiber sealing gasket can compensate deformation caused by thermal expansion and cold contraction of the steel ladle, the sealing effect is guaranteed, the dynamic sealing performance is improved, and the air leakage rate is reduced. The service life of the ladle cover is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of metal smelting and casting, and in particular relates to a high-efficiency ladle for alloy smelting. Background Art

[0002] Ladle is an important device in the metallurgical industry. Ladle metallurgy is a method of pouring crude molten steel from a steelmaking furnace into a ladle for further refining to remove impurities such as hydrogen, nitrogen, carbon and sulfur from the molten steel, adjust the temperature and composition of the molten steel, and reduce non-metallic inclusions. Ladle metallurgy usually includes argon blowing treatment of the ladle. A gas supply element is installed on the ladle to blow argon into the molten steel to form a large number of fine argon bubbles, which are used to even out the temperature and composition of the molten steel, degas and remove inclusions.

[0003] The current alloy smelting ladles have insufficient refining effects on molten steel due to structural defects, including: 1. The argon blowing treatment effect of the ladle metallurgy is not good, and the purity and uniformity of the argon input need to be improved. The existing argon protection device usually introduces a large amount of argon at the bottom or top of the ladle, which easily causes argon waste and uneven distribution of argon in the molten steel. In addition, the insufficient sealing of the ladle structure is also prone to argon leakage, and the purity of the argon in the ladle is insufficient. The above situation leads to low degassing and impurity removal efficiency after argon blowing, and the effect is not good; 2. The sealing of the ladle is not good. The sealing and heat preservation effects are poor. On the one hand, the temperature of the molten steel drops too fast during pouring and transportation to the continuous casting site, and the molten steel contacts the air over a large area. When blowing argon, the argon gas will leak and be doped due to insufficient sealing, which will reduce the quality of the finished steel. The impact of the high-temperature molten steel and the cooling effect of the large and high-speed airflow during argon blowing will also produce a significant temperature difference inside the air brick, resulting in thermal stress concentration, affecting the performance of the air brick, and then affecting the argon blowing effect; on the other hand, the excessively high temperature of the molten steel will also lead to a decrease in the viscosity, surface tension and wetting angle of the molten steel, thereby increasing the tendency of steel penetration and reducing the ladle blowing rate. Therefore, it is necessary to improve the ladle for alloy smelting to improve the efficiency of ladle smelting and the effect of the finished product. Summary of the invention

[0004] The present invention aims to solve the problem of smelting efficiency of alloy smelting ladles, specifically, the problems of low efficiency of argon blowing treatment of the ladles and poor sealing and heat preservation effects of the ladles, and proposes an efficient alloy smelting ladles.

[0005] To achieve the above object, the present invention adopts the following technical solutions: The invention discloses an efficient ladle for alloy smelting, comprising a ladle body, a ladle bottom argon blowing mechanism and a sealing ladle cover mechanism; the ladle bottom argon blowing mechanism is located at the bottom of the ladle body to realize bottom argon blowing, so as to reduce the nitrogen and hydrogen contents and the content of scrap metal inclusions in the steel, and to make the composition and temperature of the molten steel uniform; the sealing ladle cover mechanism is located at the top of the ladle column, so as to seal the top of the ladle body, avoid gas leakage and reduce the temperature loss during the ladle transfer process.

[0006] The ladle body includes a ladle shell, a nano-aerogel insulation layer, a thermal insulation layer, and a refractory working layer from the outside to the inside; a nano-aerogel insulation layer is arranged between the ladle shell and the thermal insulation layer to effectively isolate the heat inside and outside the ladle body and achieve a better thermal insulation effect.

[0007] Argon gas enters the interior of the ladle body through the ladle bottom argon blowing mechanism, and the ladle bottom argon blowing mechanism includes a rotating seat, a driving motor, and a multi-level gradient air-permeable brick. The rotating seat is installed at the bottom of the ladle body, and the driving motor is connected to the rotating seat and drives the rotating seat to rotate around its own axis. When the rotating seat rotates, it is sealed with the ladle body. The multi-level gradient air-permeable brick is arranged in the rotating seat. Different parts of the multi-level gradient air-permeable brick are provided with pores of three different diameter gradient structures, namely, coarse pores, fine pores, and micropores. The coarse pores The micropores are located on a side of the multi-level gradient air-permeable brick close to the outside of the ladle, and the micropores are located on a side of the multi-level gradient air-permeable brick close to the inside of the ladle; the driving motor controls the rotation of the rotating seat, and the multi-level gradient air-permeable bricks on the rotating seat also rotate accordingly, and the argon gas rotates with the multi-level gradient air-permeable bricks and enters the inside of the ladle body evenly, thereby improving the argon blowing effect; in addition, the pores of the multi-level gradient air-permeable bricks are distributed in a gradient structure of "coarse pores-fine pores-micropores" at different positions, so that the argon bubbles diffuse into the ladle body, the bubble volume is smaller, and it reacts more fully with the molten steel.

[0008] The sealing cover mechanism is sealed and installed on the top of the ladle body. The sealing cover mechanism includes an arc-shaped cover and a ceramic fiber sealing pad. The ceramic fiber sealing pad is installed as an inner lining on one side of the arc-shaped cover close to the inside of the ladle body. The shape of the arc-shaped cover matches the top ladle opening of the ladle body. The arc-shaped cover can better fit with the top of the ladle body, thereby improving the sealing performance. The ceramic fiber sealing pad is used as an inner lining, which has stronger resistance to slag erosion and is more stable.

[0009] In a possible implementation, the thickness of the nano aerogel thermal insulation layer is 10-20 mm.

[0010] In this implementation, the nano-aerogel insulation layer is used to isolate the heat exchange inside and outside the ladle body, thereby improving the thermal insulation effect of the ladle and reducing the temperature drop of the molten steel in the ladle body during transportation and transfer.

[0011] In a possible implementation, the outer layer of the ladle shell is coated with a high reflectivity metal coating.

[0012] In this implementation, the high-reflectivity metal coating may be an aluminum-magnesium alloy coating, which can reflect heat, reduce radiation and convection heat dissipation, and thereby reduce the temperature drop of the molten steel inside the ladle during transportation and transfer.

[0013] In a possible implementation, the diameters of the coarse pores, fine pores, and micropores of the multi-level gradient air-permeable brick are 1-1.5 mm, 0.5-0.8 mm, and 0.1-0.3 mm, respectively.

[0014] In this implementation, the diameters of coarse pores, fine pores and micropores are roughly in the ratio of 3:2:1. Argon gas is dispersed step by step through the gradient pore size, which can make the bubbles evenly refined and improve the efficiency of molten steel refining. The coarse pore layer can intercept large particles of impurities, the fine pore layer slows down the penetration of molten steel, and the blockage rate of the air brick is greatly reduced, and the anti-blockage ability is enhanced.

[0015] In a possible implementation, the outer layer of the multi-level gradient air-permeable brick is coated with a silicon nitride anti-corrosion coating.

[0016] In this implementation, the corrosion resistance of the multi-level gradient air-permeable bricks can be effectively improved, and the service life of the air-permeable bricks can be increased.

[0017] In one possible implementation, the rotating seat includes a rotating wall cylinder, a rotating shaft, and a rotating bracket. A through hole is opened at the bottom of the ladle body, and the rotating wall cylinder is seal-mounted in the through hole. The rotating shaft is located at the center of the rotating wall cylinder. The rotating shaft is connected to the drive motor and rotates under the control of the drive motor. The rotating bracket is installed on the rotating shaft. The rotating bracket rotates synchronously with the rotating shaft. The end of the rotating bracket is seal-connected to the rotating wall cylinder, and the multi-stage gradient air permeable bricks are installed in the rotating bracket in an array.

[0018] In this implementation, the rotating seat can drive the multi-level gradient air bricks to rotate periodically, and the argon gas covers a larger and more uniform bottom area inside the ladle body. During the rotation process, the flow of molten steel can flush the surface of the air bricks, reducing the blockage of the air bricks, and the rotation speed of the rotating seat can be adjusted to match the requirements of different steel grades.

[0019] In a possible implementation, an ultrasonic vibrator is installed beside the multi-level gradient air-permeable brick. The ultrasonic vibrator is connected to an argon gas source and breaks the argon bubbles into micron-sized particles before sending them into the multi-level gradient air-permeable brick.

[0020] In this implementation, the ultrasonic vibrator can shatter the argon bubbles before they enter the air bricks, thereby increasing the speed and uniformity of argon entering the ladle body, reducing the blockage rate of the air bricks, and improving the desulfurization efficiency, which is especially suitable for high-sulfur steel grades such as oil pipeline steel.

[0021] In a possible implementation, an electric heating coil and an infrared temperature measurement module are installed at the bottom of the ladle body, and the electric heating coil and the infrared temperature measurement module are both connected to a control device and maintain the temperature of the molten steel in the ladle body within a preset range.

[0022] In this implementation, the temperature of the molten steel in the ladle body can always be maintained within an optimal range, avoiding the molten steel temperature being too high or too low, and the argon gas blown at the bottom can have a certain heating effect, reducing the temperature drop of the molten steel and preventing the argon bubble temperature from being too low, causing thermal shock cracking of the breathable bricks.

[0023] In a possible implementation, the sealing cover mechanism further includes a hydraulic drive device, and the hydraulic drive mechanism is used to drive the opening and closing movement of the arc-shaped cover. In this implementation, the movement of the arc-shaped cover is more labor-saving and controllable, and the opening and closing speed is greatly accelerated.

[0024] In a possible implementation, the ceramic fiber sealing gasket is a multi-layer composite structure, including an outer dense ceramic layer, a middle porous fiber layer, and an inner flexible graphite layer.

[0025] In this implementation, the ceramic fiber sealing pad has good high-temperature adaptability, can adapt to the alloy smelting temperature and resist slag erosion; it has a good elastic pre-compression rate, can compensate for the thermal expansion and contraction deformation of the ladle, and ensure a good sealing effect on the top of the ladle body. In addition, the above-mentioned multi-layer composite structure has an outermost layer that resists corrosion, the middle layer has a heat insulation effect, and the inner layer has a good sealing effect, which extends the service life of the sealing point, and cuts off the heat transfer inside and outside the arc-shaped ladle cover, reducing the heat load of surrounding equipment.

[0026] Compared with the prior art, the present invention has the following beneficial effects: 1. Improve the argon blowing mechanism at the bottom of the ladle for alloy smelting, use multi-level gradient air-permeable bricks, the pores in the bricks are divided into "coarse-fine-micro", the closer to the ladle body, the smaller the internal pore diameter, which can make the bubbles evenly refined, improve the efficiency of molten steel refining, and enhance the anti-blocking ability of the air-permeable bricks, and the gradient structure can disperse thermal stress and extend the service life of the air-permeable bricks; the multi-level gradient air-permeable bricks are installed in an array on a rotating seat, which is driven by a motor to rotate, so that the argon bubbles can cover the inner bottom of the ladle body without dead angles, so as to fully combine and react with the molten steel, and the molten steel flows and flushes its surface when the multi-level gradient air-permeable bricks rotate, effectively reducing local blockage. The argon microbubbles and the rotating argon blowing method work together to effectively improve the dehydrogenation efficiency of the molten steel and the inclusion removal rate, and effectively improve the utilization rate of argon.

[0027] 2. Improving the ladle body of the alloy smelting ladle and adding a nano-aerogel insulation layer between the ladle shell and the insulation layer can effectively reduce radiation and convection heat dissipation, reduce the temperature drop rate, and achieve better insulation effect, thereby improving the quality of finished steel smelted by the ladle.

[0028] 3. Improve the sealing cover mechanism of the ladle for alloy smelting, and set a ceramic fiber sealing pad lined with the arc-shaped cover to reduce heat loss when opening the cover. It works synergistically with the insulation structure of the ladle body to form a multi-layer composite insulation structure as a whole, maintaining the temperature of the molten steel within the optimal smelting temperature range. The pre-compression rate of the ceramic fiber sealing pad is 30%-40%, which can compensate for the deformation of the ladle due to thermal expansion and contraction, ensure the sealing effect, improve the dynamic sealing, reduce the leakage rate, and extend the service life of the ladle. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 The schematic diagram is a structural diagram of a highly efficient ladle for alloy smelting; Figure 2 This is a schematic diagram of the structure of the bottom argon blowing mechanism; Figure 3 The structure diagram of the rotating seat is shown in FIG. Figure 4 It is a schematic diagram of the structure of the sealing cover mechanism; Figure 5 It is a schematic diagram of the longitudinal cross-sectional structure of the sealing cover mechanism in the closed state on the ladle body.

[0031] Among them, the ladle body 1, the ladle shell 11, the nano aerogel insulation layer 12, the thermal insulation layer 13, and the refractory working layer 14; Bottom argon blowing mechanism 2, rotating seat 21, rotating wall tube 211, rotating shaft 212, rotating bracket 213, driving motor 22, multi-level gradient air-permeable brick 23, coarse hole 231, fine hole 232, micro hole 233; Sealing cover mechanism 3, arc-shaped cover 31, ceramic fiber sealing pad 32; Electric heating coil 4. DETAILED DESCRIPTION

[0032] In order to further understand the purpose, structure, characteristics, and functions of the present invention, this section will describe specific embodiments of the present invention in detail.

[0033] In the description of the present invention, it should be noted that the terms "length", "width", "thickness", "center", "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly defined, the terms "set", "install", "connect" and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific content of the technical solution.

[0034] Please refer to Figures 1 to 5 , an efficient ladle for alloy smelting, comprising a ladle body 1, a ladle bottom argon blowing mechanism 2 and a sealing ladle cover mechanism 3. The molten steel is smelted in the ladle body 1, and the structure of the ladle body 1 is the same or similar to the main structure of the current alloy smelting ladle, which will not be repeated here; the ladle bottom argon blowing mechanism 2 is located at the bottom of the ladle body 1, and can be connected to an argon gas source, so that argon gas enters the ladle body 1 from the bottom to perform the ladle smelting argon blowing process; the sealing ladle cover mechanism 3 is located at the top of the ladle body 1, and can seal the top of the ladle body 1, reduce the probability of gas leakage during ladle smelting, and reduce the temperature drop of the molten steel during transfer or transportation, thereby reducing heat loss, ensuring that the temperature of the molten steel is always maintained within a certain range, and improving the quality of the finished steel.

[0035] Attached Figure 1The present invention discloses a structural schematic diagram of an efficient ladle for alloy smelting, which only discloses the relative installation positions of the ladle body 1, the ladle bottom argon blowing mechanism 2 and the sealing ladle cover mechanism 3 in the present invention, and a simple structural modification diagram, including the hierarchical structure improvement of the ladle body 1, the brief structural diagram of the argon blowing mechanism and the brief structural diagram of the sealing ladle cover mechanism 3, but does not represent the actual structure of the ladle for alloy smelting of the present invention, and common structures on the ladle are omitted. This figure is only an auxiliary reference and explanation of the specification.

[0036] Please refer to Figure 1 The ladle body 1 includes a ladle shell 11, a nano-aerogel insulation layer 12, a thermal insulation layer 13, and a refractory working layer 14 from the outside to the inside. The structure of the ladle body 1 is improved, and a nano-aerogel insulation layer 12 is added between the ladle shell 11 and the thermal insulation layer 13 to isolate heat radiation. This multi-layer composite thermal insulation structure of the ladle body 1 can reduce radiation and convection heat dissipation, and can effectively reduce the temperature drop rate when the molten steel in the ladle is transported and transferred.

[0037] In the multi-layer structure of the ladle body 1, the ladle shell 11 is usually made of steel, and its main function is to provide structural support and protect the internal refractory material from the influence of the external environment; the nano aerogel insulation layer 12 uses nano aerogel insulation material, which does not decompose or release harmful gases at high temperatures. It is the material with the lowest thermal conductivity known so far. It blocks heat transfer in all directions by inhibiting heat conduction, blocking heat convection and blocking heat radiation, thereby improving the thermal insulation effect of the ladle body 1; the insulation layer 13 can be made of refractory fiberboard, and the refractory working layer 14 includes a permanent layer and a working layer. The permanent layer can be built with clay bricks or high-alumina bricks, which have obtained good high temperature resistance and corrosion resistance and can withstand long-term contact with molten steel. The working layer can be built with high-alumina bricks, wax stone bricks or aluminum-carbon bricks, and the wire binding part can be made of magnesium-carbon bricks to improve corrosion resistance and wear resistance. The working layer can also be cast as a whole with magnesium-aluminum castables to improve the durability of the lining of the ladle body 1.

[0038] In some embodiments, the thickness of the nano aerogel insulation layer 12 is 10-20 mm. Optionally, according to actual conditions, only the nano aerogel insulation layer 12 may be retained and the thermal insulation layer 13 may be removed, thereby saving costs.

[0039] In some embodiments, the outer layer of the ladle shell 11 is coated with a high-reflectivity metal coating. Optionally, the high-reflectivity metal coating is made of aluminum-magnesium alloy, which can reflect thermal radiation and cooperate with the thermal insulation layer to form a reflection-barrier dual-effect thermal insulation structure, effectively reducing external heat radiation and convective heat dissipation, reducing the temperature drop rate, and allowing the temperature of the molten steel in the ladle for alloy smelting to be effectively maintained within an optimal range.

[0040] Please refer to Figure 1 , Figure 2 and Figure 3 Argon gas enters the interior of the ladle body 1 through the ladle bottom argon blowing mechanism 2, the ladle bottom argon blowing mechanism 2 includes a rotating seat 21, a driving motor 22, and a multi-level gradient air-permeable brick 23, the rotating seat 21 is installed at the bottom of the ladle body 1, the driving motor 22 is connected to the rotating seat 21 and drives the rotating seat 21 to rotate around its own axis, and the rotating seat 21 is sealed with the ladle body 1 when rotating, and the multi-level gradient air-permeable brick 23 is arranged in the rotating seat 21. Different parts of the interior of the multi-level gradient air-permeable brick 23 are provided with three kinds of air holes with different diameter gradient structures, namely, coarse holes 231, fine holes 232, and micro holes 233. The coarse holes 231 are located on the side of the multi-level gradient air-permeable brick 23 close to the outside of the ladle, and the micro holes 233 are located on the side of the multi-level gradient air-permeable brick 23 close to the inside of the ladle.

[0041] The ladle bottom argon blowing mechanism 2 is located at the bottom of the ladle body 1, and is connected to an argon source to realize bottom argon blowing during ladle smelting. Its purposes include: 1. Bringing nitrogen and hydrogen gases in the steel out of the molten steel, thereby reducing the nitrogen and hydrogen gas content in the steel; 2. By blowing in argon gas, the molten steel is strongly stirred, so that small particles in the molten steel collide with each other and combine into large particle inclusions, which are conducive to floating and removal, thereby reducing the inclusion content in the steel; 3. Argon blowing and stirring can make the composition and temperature of the ladle uniform, and improve the recovery rate of deoxidizers and alloy materials; 4. Bottom argon blowing can be achieved through air permeable bricks, which is simpler, faster and safer than top argon blowing.

[0042] The present invention improves the structure of the air brick and uses a multi-level gradient air brick 23. The air holes for air permeability are divided into three different levels of "coarse hole 231-fine hole 232-micro hole 233". The diameters of the three levels of air holes decrease step by step. The air holes of the coarse holes 231 are located on the side close to the outside of the ladle body 1, the air holes of the micro holes 233 are located on the side close to the inside of the ladle body 1, and the air holes of the fine holes 232 are located between the coarse holes 231 and the micro holes 233. The quick connector of the ladle bottom argon blowing mechanism 2 is connected to the connecting hose of the argon source. The argon enters the air brick, passes through the coarse holes 231, the fine holes 232, and the micro holes 233 in sequence, and finally enters the ladle body from the air holes of the micro holes 233. The interior of the breathable brick is designed with a three-layer pore size gradient. The coarse pore 231 layer has the largest pore size and is located close to the gas source, which can reduce the flow resistance of argon. The fine pore 232 layer has a moderate pore size and is an intermediate transition layer that can evenly distribute the airflow. The micropore 233 layer has the smallest pore size and contacts the molten steel inside the steel plate body. Argon passes through the micropore 233 layer to generate micron-sized argon bubbles that enter the molten steel.

[0043] The beneficial effects of using multi-level gradient brickwork include: 1. The above-mentioned structure of the air-permeable brick disperses argon through the gradient aperture step by step, and the micron-level bubbles that finally enter the molten steel have a surface area 2-3 times greater than the millimeter-level argon bubbles of the traditional single-level air-permeable brick, and enter the molten steel more evenly and finely, fully bringing out the hydrogen and nitrogen in the molten steel, and effectively agglomerating the non-metallic inclusions in the molten steel to make them float out, effectively improving the refining efficiency of the molten steel. 2. The above-mentioned structure of the air-permeable brick disperses argon through the gradient aperture step by step, and the aperture on the side that contacts the molten steel in the ladle is the smallest. The 232 layers of fine pores can effectively slow down the penetration of the molten steel, and the 231 layers of coarse pores can effectively intercept large particles of impurities, greatly increasing the anti-blocking ability of the air-permeable brick. 3. The above-mentioned structure of the air-permeable brick disperses argon through the gradient aperture step by step, and the thermal stress generated by the molten steel in the ladle is also effectively dispersed, and the life of the air-permeable brick is increased from the traditional 300 heats to 500 heats.

[0044] In some embodiments, the apertures of the coarse pores 231, fine pores 232, and micropores 233 of the multi-level gradient air-permeable brick 23 are 1-1.5 mm, 0.5-0.8 mm, and 0.1-0.3 mm, respectively. The aperture ratio of the coarse pores 231: fine pores 232: micropores 233 is approximately 3:2:1, so that the rate of argon bubbles passing through pores of different apertures is not affected, ensuring the gas flow rate and rate of argon blowing, and finally entering the molten steel from the multi-level gradient air-permeable brick 23 in micron size, and more evenly distributed.

[0045] In some embodiments, the outer layer of the multi-level gradient air-permeable brick 23 is coated with a silicon nitride anti-corrosion coating. The coating of this material is resistant to high temperatures not less than 1700°C, which can effectively protect the multi-level gradient air-permeable brick 23 from being damaged by the high temperature of the ladle smelting temperature and extend the life of the air-permeable brick.

[0046] The bottom-wrapped argon blowing mechanism 2 of the present invention is also provided with a rotating seat 21 and connected to a driving motor 22, and multi-level gradient air-permeable bricks 23 are installed in an array in the rotating seat 21. The driving motor 22 controls the rotation of the rotating seat 21, and the rotation of the rotating seat 21 drives the multi-level gradient air-permeable bricks 23 thereon to rotate. The multi-level gradient air-permeable bricks 23 can be arranged in a circular array and installed in the rotating seat 21, preferably with 6-8 multi-level gradient air-permeable bricks 23 as a group. The base of the rotating seat 21 is driven by a motor. Preferably, a servo motor can be used to drive the rotating seat 21 to facilitate its forward and reverse switching.

[0047] The beneficial effects of installing the multi-level gradient air-permeable brick 23 in the rotating seat 21 include: 1. The rotating base drives the air-permeable brick to rotate periodically, and the argon bubbles are thrown into the molten steel in the ladle body 1 by the rotation of the air-permeable brick, thereby increasing the coverage area of ​​the argon bubbles. Under the action of inertia, it can basically cover the left and right areas of the inner bottom of the ladle body 1, so that it can fully play the role of dehydrogenation and denitrification and remove non-metallic inclusions. 2. The rotating base drives the air-permeable brick to rotate. During the rotation process, the molten steel will continuously flow and flush the surface of the air-permeable brick, thereby reducing the nodules and local blockage of the air-permeable brick, and achieving a good self-cleaning effect. 3. The speed and direction of the rotating seat 21 can be controlled by adjusting the control parameters of the motor to match the argon blowing requirements of different steel grades during ladle smelting. For example, the rotating seat 21 is controlled to rotate at a low speed when high-carbon steel is smelted in the ladle, and the rotating seat 21 is controlled to rotate at a high speed when stainless steel is smelted in the ladle. Exemplarily, the speed of the motor-driven rotating seat 21 can be 0.5-2r / min.

[0048] Preferably, the motor can also be connected to an external control device, and the speed and direction of the drive motor 22 can be controlled by a gas flow closed-loop control algorithm, so that the argon flow rate of the bottom argon blowing during ladle smelting is always controlled within a better range, thereby obtaining a better argon blowing effect. The gas flow closed-loop control algorithm can dynamically adjust the argon flow rate based on the composition and temperature data of the molten steel, and use the PID algorithm to control, reduce the use of argon, avoid argon waste, and facilitate high-precision smelting.

[0049] In some embodiments, the rotating seat 21 includes a rotating wall tube 211, a rotating shaft 212, and a rotating bracket 213. A through hole is opened at the bottom of the ladle body 1, and the rotating wall tube 211 is sealed and installed in the through hole. The rotating shaft 212 is located at the center of the rotating wall tube 211. The rotating shaft 212 is connected to the driving motor 22 and rotates under the control of the driving motor 22. The rotating bracket 213 is installed on the rotating shaft 212. The rotating bracket 213 rotates synchronously with the rotating shaft 212. The end of the rotating bracket 213 is sealed and connected to the rotating wall tube 211, and the multi-stage gradient air permeable bricks 23 are installed in the rotating bracket 213 in an array. The rotating wall tube 211 cooperates with the rotating seat 21. The rotating wall tube 211 is a hollow cylindrical structure. The overall top view structure of the rotating seat 21 is circular and its diameter is equal to the inner diameter of the rotating wall tube 211. The outer periphery of the rotating seat 21 and the inner wall of the rotating wall tube 211 form a sealed turntable. When the rotating seat 21 rotates, a dynamic seal is formed between the rotating wall tube 211 to avoid argon leakage or argon mixing with air, resulting in insufficient purity. A vertically extending rotating shaft 212 is provided at the center of the rotating seat 21. The rotating shaft 212 is connected to an external driving motor 22 and rotates around the rotating shaft 212 under the control of the driving motor 22. The rotating seat 21 is evenly divided into several fan-shaped compartments around the rotating shaft 212, which are combined to form a circular array. A multi-level gradient air-permeable brick 23 with matching shape is placed in each fan-shaped compartment, and each air-permeable brick can be disassembled and replaced. Preferably, the air-permeable bricks are arranged and installed in a circular array in groups of 6-8.

[0050] In some embodiments, an agitator is arranged at the center position of the rotating seat 21, that is, at one end of the rotating shaft 212 located inside the ladle body 1, or a stirring blade is installed at one end of the rotating seat 21 close to the inside of the ladle body 1. When the rotating seat 21 rotates, the agitator or stirring blade thereon will be driven to rotate together, thereby stirring the molten steel, improving the uniformity of the molten steel composition, and shortening the refining time.

[0051] In some embodiments, an ultrasonic vibrator is installed beside the multi-level gradient air-permeable brick 23, and the ultrasonic vibrator is connected to the argon gas source and breaks the argon bubbles into micron-level and then sends them into the multi-level gradient air-permeable brick 23. The frequency of the ultrasonic vibrator can be selected to be 20-40kHz, and the cavitation effect is used to further refine the argon bubbles, and the diameter of the bubbles is quickly reduced to the micron level to improve the desulfurization efficiency, which is more suitable for high-sulfur steel grades, such as oil pipeline steel.

[0052] In some embodiments, an electric heating coil 4 and an infrared temperature measurement module are installed at the bottom of the ladle body 1. The electric heating coil 4 and the infrared temperature measurement module are connected to the control device and maintain the temperature of the molten steel in the ladle body 1 within a preset range. On the one hand, this electric heating coil 4 is arranged at the bottom of the steel plate body. In addition to heating and keeping the molten steel warm, it can also preheat the argon blowing mechanism 2 at the bottom of the ladle. The preheated argon bubbles are injected into the molten steel in the ladle body 1, which can effectively reduce the temperature drop of the molten steel, prevent the low-temperature argon gas from entering the air-permeable bricks and causing thermal shock cracking of the air-permeable bricks, and prevent the multi-level gradient air-permeable bricks 23 from contacting the molten steel at high and low temperatures, resulting in nodule blockage. The electric heating coil 4 can adjust the heating power in real time, maintain the molten steel temperature within ±5°C fluctuations, effectively avoid pollution from traditional gas preheating, and reduce energy consumption.

[0053] Please refer to Figure 1 , Figure 4 as well as Figure 5 The sealing cover mechanism 3 is sealingly installed on the top of the ladle body 1. The sealing cover mechanism 3 includes an arc-shaped cover 31 and a ceramic fiber sealing pad 32. The ceramic fiber sealing pad 32 is installed as an inner lining on one side of the arc-shaped cover 31 close to the inside of the ladle body 1. The shape of the arc-shaped cover 31 matches the top ladle mouth of the ladle body 1.

[0054] The sealing cover mechanism 3 of the present invention has been improved in structure, and adopts an arc-shaped cover 31, whose shape matches the top ladle mouth of the ladle body 1, reduces gaps, and improves the sealing effect. The arc-shaped cover 31 can use a high-temperature resistant alloy as the cover substrate, and adopts a ceramic fiber sealing pad 32. Preferably, an alumina-based ceramic fiber can be used, which is resistant to high temperatures of at least 1600°C and has a thickness of 10-20mm. It has good high-temperature adaptability, effectively resists molten steel splashing and thermal deformation, and has stronger erosion resistance. The pre-compression rate of the ceramic fiber sealing pad 32 is designed to be 30-40%, which can compensate for the thermal expansion and contraction deformation of the ladle, thereby further improving the sealing of the cover.

[0055] In some embodiments, the ceramic fiber sealing pad 32 is a multi-layer composite structure, including an outer dense ceramic layer, a middle porous fiber layer, and an inner flexible graphite layer. The outermost layer has an anti-corrosion effect, the middle layer has a heat insulation effect, and the inner layer has a good sealing effect, which prolongs the service life of the sealing point and blocks the heat transfer between the inside and outside of the arc-shaped cover 31, reducing the heat load of the surrounding equipment.

[0056] In some embodiments, the sealing cover mechanism 3 further includes a hydraulic drive device, which is used to drive the opening and closing of the arc-shaped cover 31. The hydraulic drive mechanism is connected to an external controller and can drive the arc-shaped cover 31 to open and close quickly under command control, thereby reducing heat loss when opening the cover, avoiding manual close-range operation of the high-temperature area of ​​the ladle, and reducing the risk of scalding and molten steel splashing.

[0057] The beneficial effects of using the sealing cover mechanism 3 include: 1. The arc-shaped cover 31 adopts an arc-shaped fitting design, so that the shape of the cover matches the ladle mouth, which can reduce gaps and improve the sealing effect; 2. The ceramic fiber sealing pad 32 is used to compensate for the thermal expansion and contraction deformation of the ladle through compression, improve the sealing effect of the cover, and is more resistant to high temperature and corrosion, extending the service life of the cover; 3. The hydraulic system is used to drive the cover to close quickly, shorten the opening time, quickly seal and block air from entering, reduce the amount of oxide slag generated on the surface of the molten steel, and remote control avoids manual close-range operation of the high-temperature area of ​​the ladle, reducing the risk of scalding and molten steel splashing. The arc-shaped cover 31, the ceramic fiber sealing pad 32 and the hydraulic drive system work together to effectively improve dynamic sealing, reduce heat loss, reduce energy loss, and extend service life.

[0058] The improvements in the ladle main structure, the ladle bottom argon blowing mechanism structure, and the sealing ladle cover structure of the present invention cooperate with each other to effectively improve the dynamic sealing of the top, main body, and bottom of the ladle for alloy smelting, thereby improving the thermal insulation effect, reducing energy consumption, and improving the quality of finished steel; the bottom coil induction heating also cooperates with the ladle bottom argon blowing mechanism to preheat the argon and reduce the temperature difference between the argon and the molten steel; the structural improvement of the multi-stage gradient air-permeable bricks in the ladle bottom argon blowing mechanism combined with the rotating seat can greatly improve the argon blowing effect and the efficiency of refined steel.

[0059] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0060] The present invention has been described by the above-mentioned relevant embodiments, but the above-mentioned embodiments are only examples for implementing the present invention, which are used to help understand the technical solutions and core ideas of the present application. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention; on the contrary, the technical solutions recorded in the above-mentioned embodiments can still be modified, or some of the technical features therein can be replaced by equivalents; modifications and embellishments made without departing from the spirit and scope of the present invention are all within the scope of patent protection of the present invention.

Claims

1. An efficient ladle for alloy smelting, characterized by: It includes a ladle body, a ladle bottom argon blowing mechanism and a ladle cover sealing mechanism; The ladle body includes, from outside to inside, a ladle shell, a nano-aerogel insulation layer, a thermal insulation layer, and a refractory working layer; Argon gas enters the interior of the ladle body through the ladle bottom argon blowing mechanism, and the ladle bottom argon blowing mechanism includes a rotating seat, a driving motor, and a multi-level gradient air-permeable brick. The rotating seat is installed at the bottom of the ladle body, and the driving motor is connected to the rotating seat and drives the rotating seat to rotate around its own axis. The rotating seat is sealed with the ladle body when rotating. The multi-level gradient air-permeable brick is arranged in the rotating seat. Three types of air holes with different diameter gradient structures, namely, coarse holes, fine holes and micro holes, are arranged at different parts of the interior of the multi-level gradient air-permeable brick. The coarse holes are located on the side of the multi-level gradient air-permeable brick close to the outside of the ladle, and the micro holes are located on the side of the multi-level gradient air-permeable brick close to the inside of the ladle. The sealing cover mechanism is sealingly installed on the top of the ladle body. The sealing cover mechanism includes an arc-shaped cover and a ceramic fiber sealing pad. The ceramic fiber sealing pad is installed as an inner lining on a side of the arc-shaped cover close to the inside of the ladle body. The shape of the arc-shaped cover matches the top ladle opening of the ladle body.

2. The efficient alloy smelting ladle according to claim 1, characterized in that: The thickness of the nano aerogel heat insulation layer is 10-20 mm.

3. The efficient alloy smelting ladle according to claim 1, characterized in that: The outer layer of the ladle shell is coated with a high reflectivity metal coating.

4. The efficient alloy smelting ladle according to claim 1, characterized in that: The diameters of the coarse pores, fine pores and micropores of the multi-level gradient air-permeable brick are 1-1.5 mm, 0.5-0.8 mm and 0.1-0.3 mm respectively.

5. The efficient alloy smelting ladle according to claim 1, characterized in that: The outer layer of the multi-level gradient air-permeable brick is coated with a silicon nitride anti-corrosion coating.

6. The efficient alloy smelting ladle according to claim 1, characterized in that: The rotating seat includes a rotating wall cylinder, a rotating shaft, and a rotating bracket. A through hole is opened at the bottom of the ladle body. The rotating wall cylinder is sealed and installed in the through hole. The rotating shaft is located at the center of the rotating wall cylinder. The rotating shaft is connected to the driving motor and rotates under the control of the driving motor. The rotating bracket is installed on the rotating shaft. The rotating bracket rotates synchronously with the rotating shaft. The end of the rotating bracket is sealed and connected to the rotating wall cylinder. The multi-stage gradient air permeable bricks are installed in the rotating bracket in an array.

7. The efficient alloy smelting ladle according to claim 1, characterized in that: An ultrasonic vibrator is installed beside the multi-level gradient air-permeable brick. The ultrasonic vibrator is connected to an argon gas source and breaks the argon bubbles into micron-sized ones and then sends them into the multi-level gradient air-permeable brick.

8. The efficient alloy smelting ladle according to claim 1, characterized in that: An electric heating coil and an infrared temperature measuring module are installed at the bottom of the ladle body. The electric heating coil and the infrared temperature measuring module are both connected to a control device and maintain the temperature of the molten steel in the ladle body within a preset range.

9. The efficient alloy smelting ladle according to claim 1, characterized in that: The sealing cover mechanism also includes a hydraulic drive device, and the hydraulic drive mechanism is used to drive the opening and closing of the arc-shaped cover to move.

10. The efficient alloy smelting ladle according to claim 1, characterized in that: The ceramic fiber sealing pad is a multi-layer composite structure, including an outer dense ceramic layer, a middle porous fiber layer and an inner flexible graphite layer.

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