An electrode sealing device with adaptive pressure regulation

Abstract

The application relates to a self-adaptive pressure-regulating electrode sealing device and relates to the technical field of metallurgical electric furnace equipment, wherein a sealing rubber pad and a pressing partition plate are sequentially and vertically arranged on the top of a base, a double-layer sealing cavity unit is arranged above the pressing partition plate, and a pressing cover plate is assembled at the upper end of the double-layer sealing cavity unit; a first sealing ring is arranged between the pressing partition plate, the pressing cover plate and the electrode; the double-layer sealing cavity unit is provided with a nitrogen inlet and a nitrogen outlet, electric regulating valves are arranged on the pipelines of the nitrogen, and the electric regulating valves are linked and matched with pressure sensors for detecting the pressure in the furnace. The nitrogen flowing in the cavity is utilized to perform surrounding indirect heat exchange and cooling on the electrode, high-temperature heat conducted by the electrode is effectively taken away, the working temperature of the sealing part is reduced, and rubber aging is delayed; two groups of first sealing rings with double-ladder-section structures are arranged, the first sealing rings are in concave-convex cooperation and staggered pressing with the pressing members and second sealing rings, and the first sealing rings can effectively prevent high-temperature dust-containing flue gas from leaking outward along the outer wall of the electrode.

Description

Technical Field

[0001] This invention relates to the field of metallurgical electric furnace equipment technology, and in particular to an electrode sealing device with adaptive pressure regulation. Background Technology

[0002] The energy-intensive metallurgical industry faces stringent requirements for carbon reduction, emission reduction, and energy consumption reduction. Electric furnace smelting technology, with its advantages of low energy consumption, low pollution, and strong controllability, is gradually replacing traditional smelting processes and becoming the mainstream production technology in the metallurgical industry. Among them, high-pressure closed electric furnaces, with their good sealing performance, controllable reaction, and easy collection and treatment of flue gas, are widely used in various special metallurgical, alloy smelting, and fine smelting production scenarios.

[0003] Electrodes are the core current-carrying components of high-pressure sealed electric furnaces. They vertically penetrate the furnace cover for energization, and the gap between the electrode and the furnace cover is the main point of air and gas leakage, as well as a high-risk location for seal failure. Therefore, the sealing performance, insulation performance, and dynamic adaptability of the electrode sealing device directly determine the furnace's production stability, internal pressure stability, and flue gas collection efficiency.

[0004] Currently, most electrode sealing devices used in existing high-pressure sealed electric furnaces are fixed compression sealing structures, which still have many technical defects in actual production applications. Firstly, during the smelting process, the materials inside the furnace react violently, and the furnace pressure fluctuates dynamically. Traditional sealing devices, with their fixed structures, cannot adaptively adjust the sealing compression strength according to changes in furnace pressure. At high pressures, gaps and leaks easily occur, while at low pressures, excessive compression causes aging and damage to the seals. Secondly, during the operation of the electric furnace, the electrodes are affected by current impacts and material disturbances, easily resulting in skewness and high-frequency vibrations. Existing sealing structures lack elastic gap compensation structures, and eccentric electrode movement easily causes localized wear and compression cracking of the sealing gasket, leading to seal failure. Thirdly, existing sealing devices generally have simple structures and low integration, making assembly difficult and disassembly and maintenance cumbersome, hindering rapid equipment inspection and maintenance. Fourthly, existing sealing structures generally neglect the insulation protection and heat exchange cooling requirements between the electrode and the sealing element. Long-term high-temperature operation of the electrode easily leads to heat accumulation, which not only affects the service life of the sealing element but also easily causes electrical discharge and other safety faults, posing significant safety hazards. Summary of the Invention

[0005] (a) Technical problems to be solved In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides an adaptive pressure regulation electrode sealing device, which adopts a double-layer sealing cavity in conjunction with a nitrogen pressure linkage control structure to solve the technical defects of existing high-pressure sealed electric furnace electrode sealing devices, such as inability to adapt to furnace pressure fluctuations, lack of gap compensation for electrode skew vibration, poor cooling and insulation performance, and easy seal failure.

[0006] (II) Technical Solution To achieve the above objectives, the main technical solutions adopted by the present invention include: This invention provides an adaptive pressure-regulating electrode sealing device, which is fixedly installed on the upper part of the furnace cover of an electric furnace and tightly fitted to the electrode on its inner side. The electrode vertically penetrates the interior of the device. The device includes a base, a sealing rubber gasket, a pressing partition, a double-layer sealing cavity unit, and a pressing cover plate. The base is fixed to the furnace cover. A sealing rubber gasket and a pressing partition are stacked sequentially on top of the base. The double-layer sealing cavity unit is arranged above the pressing partition, and a pressing cover plate is mounted on the upper end of the double-layer sealing cavity unit. A first sealing ring is provided between the pressing partition and the pressing cover plate and the electrode. The double-layer sealing cavity unit is composed of a sliding partition, a limiting baffle, a second sealing ring, and a surrounding cylinder. The double-layer sealing cavity unit has a nitrogen inlet and a nitrogen outlet. Both the nitrogen inlet and outlet pipelines are equipped with electric regulating valves, which work in conjunction with a pressure sensor used to detect the furnace pressure.

[0007] The double-layer sealed cavity unit has a closed cavity structure inside. The cavity is equipped with a partition, which divides the cavity into two cavities with the same upper and lower structure. The outer walls of the upper and lower cavities are respectively equipped with nitrogen inlets and nitrogen outlets. The cavity uses nitrogen to achieve electrode heat insulation and cooling and internal pressure compensation.

[0008] The upper and lower cavities of the double-layer sealed cavity unit are each provided with a sliding partition that is perpendicular to the partition. The sliding partition is slidably connected to the inner wall of the double-layer sealed cavity unit and the partition. A second sealing ring is provided between the sliding partition and the electrode. The upper and lower inner walls of the two cavities are each fixedly provided with corresponding limiting baffles.

[0009] The sliding partition slides within the cavity, working in conjunction with the limiting baffle to compensate for gaps caused by electrode misalignment and vibration.

[0010] The first sealing ring is a rotary annular component with a double-step cross-section. The two stepped sections of the first sealing ring and the pressing partition or pressing cover plate respectively form an interlocking pressing sealing structure with the double-layer sealing cavity unit.

[0011] The first sealing ring consists of two rings, which are respectively disposed on the upper and lower walls of the double-layer sealing cavity.

[0012] The first sealing ring includes a first step and a second step. The side of the first step of the two first sealing rings that is close to the double-layer sealing cavity unit is in contact with the second sealing ring inside the double-layer sealing cavity unit. The side of the first step that is away from the double-layer sealing cavity unit, together with the second step, cooperates with the groove of the pressing partition and the pressing cover plate to seal and press.

[0013] The pressing cover plate and the double-layer sealing cavity unit are locked together by pre-tightening bolts; the base, pressing partition plate, and double-layer sealing cavity unit are fixed to the furnace cover by pre-tightening bolts.

[0014] A pressure sensor is installed on the nitrogen inlet pipeline. The electric regulating valve adjusts the nitrogen inlet flow rate in real time based on the pressure signal collected by the pressure sensor, so as to achieve adaptive adjustment of the sealing pressure.

[0015] The first sealing ring is made of high-temperature resistant fluororubber, with a temperature resistance of -40℃ to 350℃, and has wear-resistant, arc-resistant, and heat-resistant properties.

[0016] (III) Beneficial Effects The beneficial effects of this invention are: 1. This invention employs a symmetrical double-layer sealed cavity structure, utilizing flowing nitrogen gas within the cavity for indirect, surrounding heat exchange cooling of the electrodes. This effectively removes the high-temperature heat conducted by the electrodes, reducing the operating temperature of the seals and delaying rubber aging. Simultaneously, nitrogen, being an inert insulating gas, can isolate electric arcs and suppress electric discharge on the electrode surface, improving the insulation safety of the device and overcoming the shortcomings of traditional sealing structures, such as insufficient cooling and poor insulation. A pressure sensor and an electrically adjustable valve are linked in the nitrogen pipeline, allowing for real-time acquisition of furnace pressure signals and dynamic adjustment of nitrogen inlet and outlet flow rates, ensuring that the internal pressure of the double-layer sealed cavity changes synchronously with the furnace pressure. It can automatically compensate for pressure fluctuations inside the furnace, avoid flue gas overflow under high pressure conditions and excessive compression and aging of the sealing ring under low pressure conditions, and significantly improve the sealing stability of the entire smelting process. The double-layer cavity is equipped with a sliding partition, which is used in conjunction with a limit baffle to limit the stroke. When the electrode is energized and generates radial deviation and high-frequency vibration, the sliding partition can slide slightly with the electrode to automatically compensate for the eccentric gap, offset the local compression stress caused by the electrode shaking, prevent the sealing ring from wearing and cracking on one side, significantly extend the service life of the sealing components, and adapt to the harsh vibration conditions of the electric furnace.

[0017] 2. This invention employs two sets of first sealing rings with a double-step cross-section. The side of the first step furthest from the double-layer sealing cavity unit, together with the second step, cooperates with the grooves of the pressing partition and pressing cover plate to achieve a tight seal. The sealing ring structure, the pressing component, and the second sealing ring engage in a concave-convex fit and staggered pressing, forming a tortuous sealing path. Compared to ordinary planar seals, this structure offers stronger sealing performance, better high-temperature resistance and deformation resistance, and can effectively prevent high-temperature dust-laden flue gas from leaking outward along the outer wall of the electrode. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the cross-sectional structure of the present invention; Figure 2 This is a schematic diagram of the external structure of the present invention; Figure 3This is a schematic diagram of the first sealing ring structure of the present invention.

[0019] The components include: 1. Electrode; 2. Furnace cover; 3. Base; 4. Sealing rubber gasket; 5. Pressing partition; 6. Pre-tightening bolt; 7. First sealing ring; 7-1. First step; 7-2. Second step; 8. Nitrogen inlet; 9. Nitrogen outlet; 10. Electric regulating valve; 11. Pressure sensor; 12. Sliding partition; 13. Second sealing ring; 14. Limiting baffle; 15. Pressing cover plate; 16. Double-layer sealed cavity unit. Detailed Implementation

[0020] To better explain and facilitate understanding of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] An adaptive pressure-regulating electrode sealing device is proposed in this embodiment of the invention, such as... Figure 1 and Figure 3 As shown, the device is fixedly installed on the upper part of the furnace cover 2 of the electric furnace. The electrode 1 vertically penetrates the inside of the device and is tightly fitted to it. It mainly includes a base 3, a sealing rubber gasket 4, a pressing partition 5, a pre-tightening bolt 6, a first sealing ring 7, a double-layer sealing cavity unit 16, and a pressing cover plate 15; Figure 3 As shown, the first sealing ring 7 includes a first step 7-1 and a second step 7-2. The double-layer sealed cavity unit 16 is equipped with a sliding partition 12, a second sealing ring 13 and a limiting baffle 14. The cavity is connected to a nitrogen inlet 8 and a nitrogen outlet 9. Electric regulating valves 10 are installed on the pipelines respectively. A pressure sensor 11 is installed at the furnace body to collect the furnace pressure in real time.

[0022] This device adopts a bottom-up stacked assembly structure. The base 3 is fixedly installed on the upper surface of the furnace cover 2. Sealing rubber gaskets 4 and pressing baffles 5 are stacked on top of the base 3. A double-layer sealing cavity unit 16 is mounted on the upper side of the pressing baffle 5, and a pressing cover plate 15 is mounted on the top of the double-layer sealing cavity unit 16. The base 3, pressing baffle 5, and double-layer sealing cavity unit 16 are locked together by pre-tightening bolts 6. The pressing cover plate 15 is also fastened to the double-layer sealing cavity unit 16 by pre-tightening bolts 6. The overall assembly is simple, the structure is compact, and the assembly centering accuracy is high.

[0023] The double-layer sealed cavity unit 16 is internally equipped with a transverse partition, dividing the cavity into two symmetrical and structurally identical sealed cavities. The outer sides of the upper and lower cavities are respectively connected to a nitrogen inlet 8 and a nitrogen outlet 9. Electric regulating valves 10 are installed on both the nitrogen inlet 8 and the nitrogen outlet 9. A pressure sensor 11 is located inside the electric furnace. The pressure sensor 11 is linked to the electric regulating valve 10 for control. During operation, the pressure sensor 11 collects the furnace pressure signal in real time and feeds it back to the control system. The electric regulating valve 10 dynamically adjusts the inlet and outlet nitrogen flow rates, changing the internal gas pressure of the double-layer sealed cavity unit 16. This allows the cavity sealing pressure to adaptively match the furnace pressure, preventing sealing failure caused by furnace pressure fluctuations. The flowing nitrogen gas introduced into the cavity not only provides circumferential heat exchange and cooling to the electrode 1, reducing thermal damage to the seals caused by high-temperature electrode conduction, but also acts as insulation, preventing electrode discharge and electrocution.

[0024] The upper and lower cavities of the double-layer sealed cavity unit 16 are both vertically arranged with sliding partitions 12. The sliding partitions 12 are perpendicular to the transverse partitions inside the cavity. The two ends of the sliding partitions 12 are slidably connected to the inner wall of the cavity and the transverse partitions, respectively, to ensure that the sliding partitions 12 can slide slightly in the radial direction. A second sealing ring 13 is installed between the sliding partitions 12 and the electrode 1. Limiting baffles 14 are fixedly installed on the inner sides of the cavity walls of both the upper and lower cavities to limit the sliding stroke of the sliding partitions 12. When the electrode 1 is subjected to current impact, high temperature deformation causing skewness or radial vibration, the sliding partitions 12 slide slightly synchronously with the electrode 1 to achieve eccentric gap compensation, counteract the compressive stress caused by electrode shaking, and avoid one-sided wear and tear of the sealing ring.

[0025] A first sealing ring 7 is installed between the pressing partition 5 and the double-layer sealed cavity unit 16, and between the pressing cover plate 15 and the double-layer sealed cavity unit 16. The first sealing ring 7 is made of high-temperature resistant fluororubber, with a temperature resistance of -40℃ to 350℃, and has wear-resistant, arc-resistant, and heat-aging-resistant properties. The first sealing ring 7 is a rotary annular part with a double-step structure in its cross-section, including a first step 7-1 and a second step 7-2. The side of the first step 7-1 away from the double-layer sealed cavity unit 16 and the second step 7-2 are embedded together in the pre-set grooves of the pressing partition 5 and the pressing cover plate 15 to achieve limiting and pressing. At the same time, the inner side of the first step 7-1 is attached to the second sealing ring 13, so that the first sealing ring 7, the pressing component, and the second sealing ring 13 form a concave-convex pressing structure, which constitutes a tortuous sealing path, greatly improving the overall airtightness of the device and effectively preventing the leakage of high-temperature dusty flue gas from the furnace.

[0026] The invention adopts a modular stacked sealing structure, which makes it easy to disassemble and assemble each component, and facilitates the replacement and maintenance of vulnerable parts such as the first sealing ring 7 and the second sealing ring 13. Combined with nitrogen pressure adaptive control, sliding eccentric compensation and double-step multi-sealing structure, it effectively solves the problems of non-adjustable sealing pressure, easy leakage due to vibration and poor cooling insulation of traditional electric furnace electrode seals. It can adapt to high temperature, high pressure and vibration metallurgical smelting conditions for a long time, and has high sealing stability and safety reliability.

[0027] During resistance furnace smelting, pressure sensor 11 collects the furnace pressure signal in real time. When the furnace pressure rises to 0.6MPa~0.7MPa, the electric regulating valve 10 is opened wider to increase the nitrogen intake. The internal pressure of the double-layer sealed cavity unit 16 increases, pushing the sliding baffle 12 inward to press the second sealing ring 13 and the first sealing ring 7, increasing the sealing pre-tightening force, counteracting the high-pressure thrust inside the furnace, and preventing the leakage of high-temperature and toxic fumes from the calcium carbide furnace. When the furnace pressure drops to 0.3MPa~0.4MPa, the electric regulating valve is closed to reduce the nitrogen flow. The cavity pressure decreases, and the sliding baffle 12 rebounds. The sealing pre-tightening force is reduced to avoid excessive compression of the first sealing ring 7 and the second sealing ring 13. During the smelting process, the electrode 1 experiences radial vibration, axial lifting and lowering, and slight tilting. The first sealing ring 7 and the second sealing ring 13 compensate for the gap by self-adaptive deformation based on their own elasticity. The sliding partition 12 adapts to the electrode offset by slight displacement, and the sealing element forms a labyrinth seal to prevent leakage. The circulating low-temperature nitrogen gas continuously removes heat from the electrode and the sealing element, and the electrode surface temperature drops from 450℃ to below 200℃, greatly improving the temperature resistance of the sealing element. At the same time, the nitrogen gas isolates the air, and the rubber ring provides insulation and isolation, preventing leakage and oxidation of the high-voltage electrode.

[0028] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An adaptive pressure-regulating electrode sealing device, fixedly installed on the upper part of the electric furnace cover and tightly fitted to the electrode on its inner side, the electrode vertically penetrating the interior of the device, characterized in that: The system includes a base, a sealing rubber gasket, a pressing partition, a double-layer sealed cavity unit, and a pressing cover plate. The base is fixed to the furnace cover. A sealing rubber gasket and a pressing partition are stacked sequentially on top of the base. The double-layer sealed cavity unit is positioned above the pressing partition, and a pressing cover plate is mounted on the upper end of the double-layer sealed cavity unit. A first sealing ring is provided between the pressing partition and the pressing cover plate and the electrode. The double-layer sealed cavity unit is composed of a sliding partition, a limiting baffle, a second sealing ring, and a surrounding cylinder. The double-layer sealed cavity unit is equipped with a nitrogen inlet pipe and a nitrogen outlet pipe. Both the nitrogen inlet and outlet pipes are equipped with electric regulating valves, which work in conjunction with a pressure sensor used to detect the furnace pressure. The double-layer sealed cavity unit has a sealed cavity structure. A partition divides the cavity into two identical cavities. The outer walls of the upper and lower cavities are respectively equipped with nitrogen inlet pipes and nitrogen outlet pipes. The cavity uses nitrogen for electrode insulation and cooling, as well as internal pressure compensation. The unit has sliding partitions perpendicular to the partition plate in both the upper and lower cavities. The sliding partitions are slidably connected to the inner wall of the double-layer sealed cavity unit and the partition plate. A second sealing ring is provided between the sliding partition and the electrode. The upper and lower walls of the two cavities are fixedly provided with corresponding limiting baffles. The sliding partition slides in the cavity and cooperates with the limiting baffles to achieve gap compensation when the electrode is misaligned or vibrates. The first sealing ring is a rotary annular part with a double-step structure in cross section. The two stepped sections of the first sealing ring and the pressing partition or pressing cover plate form an interlaced pressing and sealing structure with the double-layer sealed cavity unit. There are two first sealing rings, which are respectively set on the upper and lower walls of the double-layer sealed cavity. The first sealing ring includes a first step and a second step. The side of the first step of the two first sealing rings that is close to the double-layer sealed cavity unit is in contact with the second sealing ring in the double-layer sealed cavity unit. The side of the first step that is away from the double-layer sealed cavity unit and the second step cooperate with the grooves of the pressing partition and the pressing cover plate to seal and press.

2. The adaptive pressure regulating electrode sealing device according to claim 1, characterized in that: The pressing cover plate and the double-layer sealing cavity unit are locked together by pre-tightening bolts; the base, pressing partition plate, and double-layer sealing cavity unit are fixed to the furnace cover by pre-tightening bolts.

3. The adaptive pressure regulating electrode sealing device according to claim 1, characterized in that: A pressure sensor is installed on the nitrogen inlet pipe. The electric regulating valve adjusts the nitrogen inlet flow rate in real time based on the pressure signal collected by the pressure sensor, so as to achieve adaptive adjustment of the sealing pressure.

4. The adaptive pressure regulating electrode sealing device according to claim 1, characterized in that: The first sealing ring is made of high-temperature resistant fluororubber, with a temperature resistance of -40~350℃, and has wear-resistant, arc-resistant, and heat-resistant properties.

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