Dust-proof and negative-pressure-proof device and method for electroslag furnace

Abstract

The invention relates to the field of electroslag furnaces, and particularly discloses an electroslag furnace dust and negative pressure prevention device which comprises a main smoke hood, the lower portion of the main smoke hood is communicated with a protective gas pipeline, the upper surface of the main smoke hood is provided with an open hole for a copper rod to be inserted, the open hole is connected with an auxiliary smoke hood in a sealed mode, the auxiliary smoke hood is provided with a vertically-communicated through cavity, and the open hole is communicated with the through cavity. One side of the through cavity is communicated with a smoke exhaust pipe, the side, located on the smoke exhaust pipe, of the through cavity is communicated with an air inflow adjusting assembly used for balancing the pressure in the auxiliary smoke hood, and a sealing assembly is arranged on the upper portion of the auxiliary smoke hood, arranged at the upper end of the through cavity and used for being in sealed connection with a copper rod inserted into the through cavity. According to the device, when the dust removal pressure of dust removal equipment is not changed and the amount of generated dust changes irregularly, the smelting chamber can be always kept in the micro-positive pressure protective atmosphere, dust overflow can be conveniently controlled, the environmental protection and process requirements are considered, and the oxygen content of steel smelted by the electroslag furnace is reduced.

Description

Technical Field

[0001] The invention relates to the field of electric slag furnaces, and in particular to a dust and negative pressure prevention device and method for electric slag furnaces. Background Art

[0002] The characteristic of protective atmosphere electroslag furnace is that it relies on the change of weighing system that measures the mass of conductive copper rod and consumable electrode to control the melting speed accurately. During smelting, protective gas is continuously introduced into the melting chamber to form a protective atmosphere that isolates air from the melting interface, reduces the oxygen content in the ingot, and improves the quality of the ingot. Figure 3As shown, the structure of the existing smelting chamber 12 is as follows: a lower smoke hood 102 equipped with a protective gas pipe is placed on the crystallizer 13, and an upper smoke hood 101 equipped with a smoke exhaust pipe is placed on the lower smoke hood 102. The upper smoke hood 101 and the lower smoke hood 102 together constitute a main smoke hood 1, which is used for the components of the protective atmosphere and the collection and treatment of dust. The copper rod 10 passes through the upper smoke hood and enters the smelting chamber. During the smelting process, the partially melted liquid slag 15 re-solidifies and enters the smelting chamber in the form of dust. In addition to the continuous supply of protective gas, a positive pressure is formed in the smelting chamber. The dust removal equipment discharges the dust and excessive protective gas from the smelting chamber through the smoke exhaust pipe on the upper smoke hood, so that the smelting chamber maintains a slight positive pressure. During smelting, the crystallizer, lower smoke hood, and upper smoke hood are stationary parts. Sealing rings are installed between the crystallizer and the lower smoke hood, and between the lower smoke hood and the upper smoke hood, and the sealing is good; the copper rod is used to clamp the consumable electrode to do the lifting movement in the Z direction and the fine-tuning movement in the X and Y directions with a maximum stroke of 40mm, where the X, Y, and Z directions represent the three vertical directions of the horizontal, vertical, and longitudinal directions in the space, respectively. In order to meet the requirements of the weighing system, a certain gap is required between the copper rod and the upper smoke hood to avoid friction, and the upper smoke hood cannot interfere with the copper rod's fine-tuning movement in the X and Y directions. It is necessary to design active parts, so the sealing between the upper smoke hood and the copper rod is poor. A movable G10 (glass fiber and epoxy resin composite material) plate is placed on the upper part of the upper smoke hood, and the limit plate is fixed by 4xM8 bolts installed on the upper smoke hood to prevent the G10 plate from moving upward. The inner hole of the G10 plate is a countersunk structure, and a circle of wool felt is placed on the countersunk hole. The aluminum ring is installed on the G10 plate by screws to compress the wool felt. There is a gap of 2mm between the wool felt and the copper rod. Before smelting, the copper rod clamps the consumable electrode 13 to make fine-tuning movements in the X direction and the Y direction: the copper rod pushes the softer wool felt, and the wool felt is pressed until the G10 plate is pushed after being stressed. After long-term movement in the X direction and the Y direction, the wool felt is damaged, the aluminum ring falls off, the inner hole of the G10 plate is worn, and the gap between the G10 plate and the copper rod becomes larger. The dust generated during smelting moves upward under the influence of high temperature, and it is easier to overflow from the copper rod and the upper smoke hood. It is necessary to improve the dust removal suction to prevent dust from entering the atmosphere and causing environmental pollution, or entering the tight parts of the equipment to cause jamming, or causing the carbon brushes that cooperate with the copper rod to conduct electricity to overheat or even arc, causing damage, and need to be replaced and repaired, which increases the maintenance cost and reduces production efficiency.

[0003] The amount of dust generated during the smelting process changes irregularly with the change of smelting current. It is impossible to dynamically adjust the dust removal suction to cope with the changing dust amount. Only a fixed dust removal suction that meets the maximum dust amount can be selected. When the dust generation is less, the protective gas is discharged from the smelting chamber in large quantities, and a negative pressure state is formed in the smelting chamber. The atmosphere enters the smelting chamber from between the copper rod and the upper smoke hood. The oxygen content in the smelting chamber increases, which seriously affects the quality of the steel ingot 16. In order to ensure low oxygen content, it is sometimes necessary to shut down the dust removal equipment or reduce the dust removal suction. The reduced dust removal suction is likely to cause insufficient dust suction at the far end, which is not enough to be completely sucked into the dust removal equipment. Part of the dust enters the atmosphere and pollutes the environment. When the dust is too large, the overflow port needs to be blocked, and the operation is cumbersome. Therefore, the original structure cannot take into account both environmental protection and process requirements by adjusting the dust removal suction, and there are defects, which need to be modified and optimized. Summary of the invention

[0004] The purpose of the present invention is to provide an electroslag furnace dust and negative pressure prevention device, which can keep the smelting chamber in a slightly positive pressure protective atmosphere when the dust removal pressure of the dust removal equipment remains unchanged and the amount of dust generated changes irregularly. Dust overflow can be easily controlled, taking into account environmental protection and process requirements, and reducing the oxygen content of steel after smelting in the electroslag furnace.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A dust and negative pressure prevention device for an electric slag furnace comprises a main smoke hood, the lower portion of which is connected to a protective gas duct, the upper surface of which is provided with an opening for inserting a copper material rod, the opening being sealedly connected to an auxiliary smoke hood, the auxiliary smoke hood having a through cavity connected up and down, the opening being connected to the through cavity, one side of the through cavity being connected to a smoke exhaust pipe, the through cavity being located on one side of the smoke exhaust pipe and being connected to an air intake regulating component for balancing the pressure in the auxiliary smoke hood, a sealing component being provided on the upper portion of the auxiliary smoke hood, the sealing component being arranged at the upper end of the through cavity for sealingly connecting to the copper material rod inserted into the through cavity.

[0007] In a further scheme, the auxiliary smoke hood includes a limit plate, a dust plate, an upper flange, a plurality of side wall plates and a lower flange which are tightly connected to each other on the upper and lower surfaces in sequence. The lower flange is connected to the sealing plate by bolts. The sealing plate is sealed and connected to the opening on the upper surface of the main smoke hood. The limit plate, the dust plate, the upper flange, the plurality of side wall plates and the lower flange are provided with through holes in the middle parts. The limit plate, the dust plate, the upper flange, the plurality of side wall plates and the through holes in the middle parts of the lower flange are connected in sequence to form the through cavity. The dust plate is connected to the limit plate to form the sealing assembly. The wall of the through hole in the middle part of the dust plate is connected with the gap of the inserted copper rod. The limit plate is used to press the dust plate tightly outside the copper rod.

[0008] In a further solution, the limit plate, dustproof plate, upper flange, multiple side wall plates and lower flange are connected to each other by bolts, so that the upper and lower surfaces are pressed against each other in sequence.

[0009] In a further solution, the distance from the bolt to the dustproof plate is obtained according to the swing stroke of the copper rod at the dustproof plate.

[0010] In a further solution, the gap between the dustproof plate and the wall of the copper rod is less than 2 mm.

[0011] In a further solution, the air intake volume regulating component includes an air intake pipe and a flow regulating valve. The air intake pipe is located at one end of the cavity wall of the through cavity and its opening is opposite to the smoke exhaust pipe at one end of the cavity wall of the through cavity. The flow regulating valve is connected to the air intake pipe to regulate the air flow entering the through cavity.

[0012] In a further solution, the position of the smoke exhaust pipe on the cavity is determined according to the height of the dust overflowing into the cavity.

[0013] In a further solution, the smoke exhaust pipe is connected to a fan.

[0014] On the other hand, the present invention proposes a method for preventing dust and negative pressure in an electric slag furnace through the same inventive concept, and applies any of the above-mentioned dust and negative pressure prevention devices for an electric slag furnace; by adjusting the gas flow rate entering the through cavity through the air intake regulating component on one side of the exhaust pipe, the dust removal suction force at the exhaust pipe is balanced to prevent the protective gas in the smelting chamber of the electric slag furnace from being sucked away to form a negative pressure.

[0015] In a further embodiment, the method for adjusting the gas flow rate includes:

[0016] The flow rate of gas entering the through cavity from the air intake regulating component is adjusted by the flow regulating valve;

[0017] During the arc starting stage of smelting, the flow regulating valve is opened to the maximum position to maximize the gas flow into the through cavity and reduce the dust suction in the main fume hood. When part of the dust overflows from the auxiliary fume hood and the copper rod to the outside of the auxiliary fume hood, the flow regulating valve is gradually closed to make the overflowed dust just disappear, thus completing the adjustment.

[0018] Beneficial effects of the present invention:

[0019] The present invention arranges a secondary smoke hood installed on the upper end of the main smoke hood to collect dust overflowing from the main smoke hood and excess protective gas, and simultaneously eliminates the smoke exhaust pipe on the original main smoke hood, that is, the existing dust removal system does not directly extract the dust and protective gas in the smelting chamber, but only concentrates on processing the dust and gas overflowing from the upper end of the main smoke hood, and balances the dust removal suction force through the air intake adjustment component, thereby avoiding the problem of excessive dust removal suction force in the existing structure, excessive extraction of protective gas, resulting in negative pressure in the smelting chamber, and increased oxygen content in the smelting chamber causing high oxygen content in the steel.

[0020] Only the dustproof plate of the auxiliary smoke hood is in contact with the copper rod, so the auxiliary smoke hood body has a long service life and the copper rod has little wear. The dustproof plate is an elastic wear-resistant plate, such as an elastic wear-resistant plate made of wool felt, which is wear-resistant, cheap, and economical to replace.

[0021] The air intake flow rate is adjusted by the flow control valve, the ball valve opening is adjusted according to the maximum dust overflow from the main hood, and the adjustment standard is that the dust just does not overflow from the auxiliary hood. It is easy to operate and adjust, has high controllability of dust, and greatly reduces environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 Schematic diagram of a dust and negative pressure prevention device for an electroslag furnace according to an embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of an auxiliary smoke hood in an embodiment of the present invention;

[0025] Figure 3 It is a schematic diagram of the installation of an electroslag furnace dust and negative pressure prevention device and an existing smelting chamber in an embodiment of the present invention;

[0026] In the figure: 1. main smoke hood; 101. upper smoke hood; 102. lower smoke hood; 2. auxiliary smoke hood; 3. exhaust pipe; 4. air intake adjustment component; 41. air intake pipe; 42. flow control valve; 5. limit plate; 6. dust plate; 7. upper flange; 8. side wall plate; 9. lower flange; 10. sealing plate; 10. copper material rod; 12. smelting chamber; 13. crystallizer; 14. electrode; 15. slag; 16. steel ingot; 17. protective gas pipeline. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] See also Figure 3 As shown, a dust and negative pressure prevention device for an electroslag furnace comprises a main smoke hood 1, the lower part of which is connected to a protective air pipe 17. Figure 1 As shown, an opening for inserting a copper rod 11 is provided on the upper surface of the main smoke hood 1, and an auxiliary smoke hood 2 is sealedly connected to the opening. The auxiliary smoke hood 2 has a through cavity connected up and down, and a smoke exhaust pipe 3 is connected on one side of the through cavity. The through cavity is located on one side of the smoke exhaust pipe 3 and is connected to an air intake regulating component 4 for balancing the pressure in the auxiliary smoke hood 2. A sealing component is provided on the upper part of the auxiliary smoke hood 2, and the sealing component is arranged at the upper end of the through cavity for sealing connection with the copper rod inserted into the through cavity.

[0029] Its working principle or usage is: Figure 3 and Figure 1 As shown, the dust and negative pressure prevention device of the electroslag furnace is sealed and connected to the existing smelting chamber 12. By adjusting the gas flow rate entering the cavity through the air intake regulating component 4 on one side of the exhaust pipe 3, the dust removal suction force at the exhaust pipe 3 is balanced to prevent the protective gas in the electroslag furnace smelting chamber from being sucked away to form a negative pressure.

[0030] According to the above principle or method, the present invention is described by using a protective atmosphere electroslag furnace with a copper rod 11 having a diameter of φ280 mm. Figure 2 As shown, the auxiliary fume hood 2 includes an upper flange 7, a lower flange 9, a plurality of side wall plates 8, a stop plate 5 and a dust plate 6. The stop plate 5, the dust plate 6, the upper flange 7, the plurality of side wall plates 8 and the lower flange 9 are tightly connected to each other on the upper and lower surfaces in sequence. The stop plate 5, the dust plate 6, the upper flange 7, the plurality of side wall plates 8 and the lower flange 9 are provided with through holes in the middle. The stop plate 5, the dust plate 6, the upper flange 7, the plurality of side wall plates 8 and the through holes in the middle of the lower flange 9 are connected in sequence to form a through cavity. The gap between the through hole wall in the middle of the dust plate 6 and the rod wall of the copper material rod 11 inserted is less than 2 mm. The dust plate 6 is an elastic wear-resistant plate. The through cavity formed by the side wall plate 8 of the auxiliary fume hood 2 and the upper flange 7, the lower flange 9 and the copper material rod 11 is used to collect dust and protective gas overflowing from the upper fume hood 101 in the smelting chamber 12.

[0031] The specific limit plate 5, dust plate 6, upper flange 7, multiple side wall plates 8 and lower flange 9 are connected to each other by bolts, so that the upper and lower surfaces are tightly connected to each other in turn. The M10 bolts are selected to fully meet the strength requirements, and the bolt holes are φ12mm. The size of the bolt hole from the edge of the structure is generally ≥1.5D, that is, 18mm. The auxiliary smoke hood 2 as a whole needs to meet certain sealing and magnetic isolation, and is easy to process and manufacture. The material of the side wall plate 8 is wool felt. Because the strength of the wool felt material is relatively low, the size of the bolt hole from the edge of the structure is expanded to 2D, so the bolt hole pitch circle is φ460mm and the outer diameter of the wool felt is φ520mm. For ease of processing, the wool felt uses 6 plates with a thickness of 20mm respectively. The total height is 120mm in the free state. The wool felt is compressed during installation. The total height after overall compression is 112mm, which meets the design requirements. In order to ensure that the adjacent wool felts are tightly combined, 8 sets of bolt connections are designed.

[0032] The lower flange 9 is used to connect the G10 plate and other parts of the auxiliary smoke hood 2, and 2 sets of bolt through holes need to be designed. The lower flange 9 needs to be in reliable contact with the G10 plate to prevent dust from overflowing, so the bolt holes connected to other parts of the auxiliary smoke hood 2 are designed with a countersunk structure so that the heads of the connecting bolts do not protrude from the bottom plane of the lower flange 9. Its pitch circle is φ460mm, and the bolt holes are 8xφ12mm. The lower flange 9 should not contact the copper rod 11, and it needs to support the side wall plate 8, and the inner hole size is φ340mm. The side wall plate 8 with an outer circle size of φ520mm is installed on the lower flange 9. In order to facilitate the installation of the connecting bolts between the lower flange 9 and the G10 plate, the pitch circle diameter of the bolt holes connecting the lower flange 9 and the G10 plate is φ550mm. The connection between the lower flange 9 and the G10 plate is made of 4 sets of M10 bolts to fully meet the strength requirements. The bolt hole is φ12mm, and the distance between the bolt hole and the edge of the structure is generally ≥1.5D, i.e. 18mm. After rounding, the outer circle size of the lower flange 9 is φ600mm. The thickness is 20mm, which meets the structural strength requirements. The material is the epoxy resin that is magnetically isolated, insulating, and lightweight.

[0033] The upper flange 7 is matched with the lower flange 9 to install the side wall plate 8, so the bolt hole is 8xφ12mm, and its pitch circle is φ460mm. The upper flange 7 needs not to contact the copper rod 11 and form a certain obstruction effect on the upward overflow of the dust collected by the auxiliary smoke hood 2. The inner hole size of the upper flange 7 is φ340mm. The bolt hole is generally ≥1.5D from the edge of the structure, that is, 18mm. After rounding, the outer circle size of the lower flange 9 is φ510mm. The thickness is 20mm to meet the structural strength requirements. The material is epoxy resin.

[0034] The exhaust pipe 3 uses a steel pipe with an inner diameter of φ40mm and a length of 100mm for easy connection with the dust removal system. The steel pipe is composed of two 2mm thick arc plates clamped and welded to form the exhaust pipe 3 assembly. The arc plate is fixed by the auxiliary smoke hood 22 sets of adjacent connecting bolts, so the bolt hole index circle is φ460mm, the hole diameter is φ12mm, the inner and outer arc radii are R205mm and R260mm respectively with reference to the side wall plate 8 and the space size, and the arc plate width is 220mm according to the bolt hole spacing. The gap between the inner and outer arc plates and the exhaust pipe 3 can be sealed by felt and other sealing parts.

[0035] The distance from the dust plate 6 to the bolt is obtained according to the swing stroke of the copper rod at the dust plate 6. A movable dust plate 6 matching the copper rod 11 is placed on the upper part of the upper flange 7. In order to avoid friction between the dust plate 6 and the copper rod 11, a gap of 2mm is designed, and the inner hole of the dust plate 6 is φ284mm. The dust plate 6 cannot interfere with the combination bolts of the auxiliary smoke hood 2 when the copper rod 11 is pushed at the maximum stroke, and the spacing between the connecting bolts of the auxiliary smoke hood 2 is 460-12=448mm, so the outer diameter of the dust plate 6 should not be greater than 448-40=408mm. After rounding, the outer diameter of the dust plate 6 is φ400mm. The material is a wool felt with a thickness of 20mm, which has moderate flexibility and rigidity, and is easy to be pushed by the copper rod 11 without damaging the copper rod 11.

[0036] The limit plate 5 is used to limit the upward movement of the dust plate 6. The inner diameter of the dust plate 6 is larger than the diameter of the copper rod 11. After the copper rod 11 moves in the X and Y directions, there is only point contact with the dust plate 6, and the friction force is extremely small. The limit plate 5 uses a 5mm thick epoxy resin plate to meet the strength requirements. The limit plate 5 is installed on the bolts of the auxiliary smoke hood 2. The bolt hole is 8xφ12mm and the dividing circle is φ460mm. The inner hole size refers to the inner diameter of the upper flange 7 and is φ340mm, which meets the conditions for limiting the dust plate 6. The size of the bolt hole from the edge of the structure is generally ≥1.5D, that is, 18mm. The outer diameter of the limit plate 5 is rounded to φ510mm.

[0037] The air intake regulating assembly 4 includes an air intake pipe 41 and a flow regulating valve 42. The flow regulating valve 42 is connected to the air intake pipe 41 to regulate the air flow entering the through cavity. The flow regulating valve 42 can be a one and a quarter ball valve. The way the air intake pipe 41 is inserted into the side wall plate 8 can refer to the above-mentioned setting of the smoke exhaust pipe 3.

[0038] The position of the exhaust pipe 3 on the cavity is obtained according to the height of the dust overflowing into the cavity. Through long-term observation of the flow state of the dust overflowing during smelting in a protective atmosphere electroslag furnace with the exhaust pipe 3 closed or blocked and the inner hole of the G10 plate completely enlarged, it is found that the dust overflows from the gap between the upper smoke cover 101 and the copper rod 11 and moves upward for about 100mm before becoming significantly thinner. After overflowing, it spreads to the surroundings and becomes significantly thinner with a diameter of about φ390mm. Therefore, the position of the dust exhaust pipe is set by referring to the dust area to better collect the overflowed dust.

[0039] A sealing plate 10 is provided between the auxiliary smoke hood 2 and the main smoke hood 1, and the auxiliary smoke hood 2 and the main smoke hood 1 are sealed and connected by the sealing plate 10. The sealing plate 10 of the protective atmosphere electroslag furnace with a copper rod 11 having a diameter of φ280mm can adopt a ring plate of the G10 plate, and the size of the ring plate is φ800mmxφ322mmx40mm, as a base connected to the lower flange 9, the copper rod 11 does not push the G10 plate when moving in the X direction and the Y direction, and does not contact the G10 plate at the extreme position. In conjunction with the lower flange 9, 4 M10x15 threaded holes are machined on the G10 plate, and the threaded hole graduation circle is φ550mm. Because the copper rod 11 does not push the G10 plate when moving in the X direction and the Y direction, the G10 plate will not move upward due to friction.

[0040] During assembly, the components are assembled from bottom to top with the bolt holes corresponding to each other: the lower flange 9, the two side wall panels 8, the two side wall panels 8 are inserted into the integral component composed of the exhaust pipe 3 assembly and the air intake adjustment assembly 4, and the exhaust pipe 3 and the air intake adjustment assembly 4 can be relatively arranged and inserted into the two side wall panels 8; 8 bolts are inserted from the lower flange 9 and the nuts are tightened; the dustproof plate 6 is placed on the upper flange 7 and the limit plate 5 is installed, and a nut is installed above and below each bolt hole of the limit plate 5, and the position of the lower nut is adjusted so that the gap between the dustproof plate 6 and the copper rod 11 is 2mm, and the upper nut is tightened to limit the upward movement of the dustproof plate 6 and prevent the dustproof plate 6 from being deformed by force when the copper rod 11 swings in the X and Y directions.

[0041] The end of the smoke exhaust pipe 3 away from the through cavity is connected to a fan. The fan can use a fan in an existing dust removal system to provide dust suction power.

[0042] The above-mentioned auxiliary smoke hood 2 can also be made into an integral body or partial components into an integral body through magnetic insulation materials, such as an aluminum smoke hood, or made into an integral body with part of the main smoke hood 1, which can also solve the problem of the present invention. The dust and negative pressure prevention device formed by electric slag furnaces of different sizes and models that can be adapted according to the above-mentioned principles or schemes should all be included in the scope disclosed by the present invention.

[0043] The flow rate of gas entering the through cavity from the air intake regulating component 4 is adjusted by the flow regulating valve 42;

[0044] During the arc starting stage of smelting, the flow regulating valve 42 is opened to the maximum position to maximize the gas flow into the cavity and reduce the dust suction force in the main smoke hood 1. When part of the dust overflows from between the auxiliary smoke hood 2 and the copper material rod 11 to the outside of the auxiliary smoke hood 2, the flow regulating valve 42 is gradually closed to make the overflowed dust just disappear, thus completing the adjustment.

[0045] The use of the above-mentioned electric slag furnace dust and negative pressure prevention device and method can reduce the oxygen content of the refined steel ingot from more than 1% to less than 1 / 1000, thereby reducing the cost of treatment caused by environmental pollution.

[0046] It should be noted that the terms "first", "second", etc. in this application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so as to describe the embodiments of the present application described here.

[0047] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0048] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A dust and negative pressure prevention device for an electroslag furnace, comprising a main smoke hood (1), the lower part of which is connected to a protective gas duct (17), and the upper surface of which is provided with an opening for inserting a copper rod (11), characterized in that: The opening is sealedly connected to a secondary smoke hood (2), the secondary smoke hood (2) having a through cavity connected up and down, the opening being connected to the through cavity, one side of the through cavity being connected to a smoke exhaust pipe (3), the through cavity being located on one side of the smoke exhaust pipe (3) and being connected to an air intake regulating component (4) for balancing the pressure in the secondary smoke hood (2), the upper part of the secondary smoke hood (2) is provided with a sealing component, the sealing component being arranged at the upper end of the through cavity and being used for sealing connection with a copper rod (11) inserted into the through cavity.

2. The dust and negative pressure prevention device for an electroslag furnace according to claim 1, characterized in that: The auxiliary smoke hood (2) comprises a limit plate (5), a dust plate (6), an upper flange (7), a plurality of side wall plates (8) and a lower flange (9) which are tightly connected to each other on the upper and lower surfaces in sequence. The lower flange (9) is connected to the sealing plate (10) by bolts. The sealing plate (10) is sealed and connected to the opening on the upper surface of the main smoke hood (1). The limit plate (5), the dust plate (6), the upper flange (7), the plurality of side wall plates (8) and the lower flange (9) are provided with through holes in the middle. The through holes in the middle of the limit plate (5), the dust plate (6), the upper flange (7), the plurality of side wall plates (8) and the lower flange (9) are connected in sequence to form the through cavity. The dust plate (6) is connected to the limit plate (5) to form the sealing assembly. The wall of the through hole in the middle of the dust plate (6) is loosely connected to the inserted copper rod (11). The limit plate (5) is used to press the dust plate (6) outside the copper rod (11).

3. The dust and negative pressure prevention device for an electroslag furnace according to claim 2, characterized in that: The limit plate (5), the dustproof plate (6), the upper flange (7), the plurality of side wall plates (8) and the lower flange (9) are connected to each other via bolts, so that the upper and lower surfaces are tightly connected to each other in sequence.

4. The dust and negative pressure prevention device for an electroslag furnace according to claim 3, characterized in that: The distance from the bolt to the dustproof plate (6) is obtained according to the swing stroke of the copper rod at the dustproof plate (6).

5. The dust and negative pressure prevention device for an electroslag furnace according to claim 2, characterized in that: The gap between the dustproof plate (6) and the wall of the copper rod (11) is less than 2 mm.

6. The dust and negative pressure prevention device for an electroslag furnace according to claim 1, characterized in that: The air intake regulating component (4) comprises an air intake pipe (41) and a flow regulating valve (42); the air intake pipe (41) is located in the cavity wall of the through cavity and one end of the opening is directly opposite to the one end of the smoke exhaust pipe (3) located in the cavity wall of the through cavity; the flow regulating valve (42) is connected to the air intake pipe (41) and is used to regulate the air flow entering the through cavity.

7. The dust and negative pressure prevention device for an electroslag furnace according to claim 1, characterized in that: The position of the smoke exhaust pipe (3) on the through cavity is determined according to the height of dust overflowing into the through cavity.

8. The dust and negative pressure prevention device for an electroslag furnace according to claim 1, characterized in that: The smoke exhaust pipe (3) is connected to a fan.

9. A method for preventing dust and negative pressure in an electroslag furnace, characterized in that: The dust and negative pressure prevention device for an electroslag furnace as claimed in any one of claims 1 to 8 is applied; by adjusting the gas flow rate entering the through cavity through the air intake regulating component (4) on one side of the exhaust pipe (3), the dust removal suction force at the exhaust pipe (3) is balanced to prevent the protective gas in the electroslag furnace smelting chamber from being sucked away to form a negative pressure.

10. The method for preventing dust and negative pressure in an electroslag furnace according to claim 9, characterized in that: The gas flow rate adjustment method includes: The flow rate of gas entering the through cavity from the air intake regulating component (4) is adjusted by a flow regulating valve (42); During the arc starting stage of smelting, the flow regulating valve (42) is opened to the maximum position to maximize the gas flow into the through cavity, thereby reducing the dust suction force in the main smoke hood (1). When part of the dust overflows from between the auxiliary smoke hood (2) and the copper material rod (11) to the outside of the auxiliary smoke hood (2), the flow regulating valve (42) is gradually closed to make the overflowed dust just disappear, thus completing the adjustment.

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