Electric arc furnace utilizing waste heat

Abstract

The invention discloses a waste heat utilization electric arc furnace, and relates to the technical field of electric arc furnaces. The sealing problem is solved. The device specifically comprises a furnace body, a power distribution cabinet and a lifting frame, the furnace body is supported or fixed to the ground through supporting legs, a furnace cover is arranged on the top of the furnace body in a matched mode, a plurality of electrodes are inserted into the inner wall of the furnace cover in a penetrating mode, a negative pressure pump used for exhausting is installed on one side of the furnace cover, and the lifting movement end of the lifting frame is fixedly connected to the furnace cover. By arranging the sealing frame, the cambered surface flexible pad, the first sealing cavity and other components, on the basis that the insertion depth of the electrode and the furnace cover can be relatively adjusted, overall sealing can be achieved through the end face sealing pad and the flexible sealing ring pad, leakage is prevented, the attaching pressure of the flexible sealing ring pad is affected by the sealing state, and the sealing effect is good. And the electrode is automatically attached for sealing in a sealing state, and is automatically contacted with a strong sealing state in a non-working state, so that the adjustment of a fixing point of the electrode and the secondary adjusting frame is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of electric arc furnaces, and in particular to an electric arc furnace for utilizing waste heat. Background Art

[0002] A vacuum arc furnace is an electric furnace that uses an electric arc to directly heat and melt metal in a vacuum furnace body. The furnace body is a closed container that is evacuated or filled with inert gas. After the electrodes introduced from the furnace top and the water-cooled crystallizer at the furnace bottom are energized and struck, an arc is generated, and the heat of the arc melts the metal or alloy and solidifies it in the crystallizer.

[0003] After searching, the Chinese patent publication number CN118960374B discloses an electrode clamping device for a vacuum consumable arc furnace, including a lifting mechanism, which is installed on the vacuum consumable arc furnace, and a clamping tube is fixedly installed at the output end of the lifting mechanism, and an electrode rod is inserted into the inside of the clamping tube. The two ends of the electrode rod are respectively provided with matching connecting structures, so that another electrode rod can be connected to one end of the electrode rod below it through the connecting structure, and a conductive tile is provided on the inner wall of the clamping tube.

[0004] The above patent has the following deficiencies: it utilizes a longitudinal and adjustable clamping device to clamp the electrode, but since the electrode is inserted into the furnace cover, there must be a gap between the electrode and the furnace cover, and the furnace is in a vacuum state, which causes leakage in the furnace relative to the external environment, and the vacuum environment in the furnace cannot be reliably guaranteed. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an electric arc furnace for utilizing waste heat.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A waste heat utilization electric arc furnace comprises a furnace body, a power distribution cabinet and a lifting frame. The furnace body is supported or fixed to the ground by supporting legs. A furnace cover is provided on the top of the furnace body. A plurality of electrodes are inserted through the inner wall of the furnace cover. A negative pressure pump for exhaust is installed on one side of the furnace cover. The lifting end of the lifting frame is fixedly connected to the furnace cover, and the lifting end of the lifting frame is connected to the secondary adjustment frame through a lifting mechanism, and the plurality of electrodes are fixed to the inner wall of the secondary adjustment frame, and the outer wall of the electrode is provided with a sealing frame, and the sealing frame is fixed to the bottom of the secondary adjustment frame; The sealing frame is matched with the electrode gap, and the inner wall of the sealing frame is provided with a sealing cavity 1 that matches the number and position of the electrodes, and the middle part of the sealing frame is provided with a sealing cavity 2. The inner wall of the sealing cavity 1 is bonded with a flexible sealing ring gasket that fits the outer surface of the electrode, and the bottom of the sealing cavity 2 is bonded with an arc-surface flexible gasket. The arc-surface flexible gasket and the top inner wall of the sealing cavity 2 are provided with elastic parts, and the bottom outer wall of the sealing frame is bonded with an end face sealing gasket, and the sealing cavity 2 is connected with the sealing cavity 1 through a connecting cavity.

[0007] Preferably: a discharge valve is provided on one side of the furnace body, and two supporting legs located on the discharge valve side are rotatably connected to the furnace body through a rotating shaft, and a telescopic rod is provided on the inner wall of the supporting leg away from the discharge valve side, and the telescopic end of the telescopic rod is rotatably connected to a connecting rod, and the other end of the connecting rod is rotatably connected to the outer wall of the furnace body.

[0008] Furthermore: the furnace body has a cavity interlayer, the cavity interlayer is in a vacuum state, and a water-cooled wall is fixed to the outer wall of the furnace body, a heat exchanger is fixed to the outer wall of the furnace body, and the heat exchanger is a dual-channel heat exchanger, one channel of the heat exchanger is respectively connected to the two ends of the water-cooled wall, and the other channel of the heat exchanger is connected to the circulating water system.

[0009] On the basis of the above scheme: a cylinder is welded on one side of the furnace cover, and a limit ring 1 and a limit ring 2 are respectively fixed on both sides of the inner wall of the cylinder, the inner wall of the cylinder located between the limit ring 1 and the limit ring 2 is slidably connected with a cavity piston, and the side wall of the cylinder is connected to an arc head limit rod for limiting the movement of the cavity piston through a spring 1, one side of the limit ring 1 is buckled with a spring 2, and the other end of the spring 2 is buckled to the side wall of the cavity piston.

[0010] A better solution among the above solutions is: a pair of electrode half rings are fixed to the side wall of the limiting ring 2, and another pair of electrode half rings are fixed to the outer wall of the cavity piston on one side of the electrode half ring, and the two pairs of electrode half rings cooperate with each other and are connected in series in the power supply circuit of the distribution cabinet to the negative pressure pump.

[0011] As a further solution of the present invention: a pair of electrode rings are fixed to the side wall of the limiting ring 1, and another pair of electrode rings are fixed to the outer wall of the cavity piston on one side of the electrode half ring. The two pairs of electrode rings cooperate with each other and are connected in series in the power supply circuit of the distribution cabinet to the electrodes.

[0012] At the same time, the power supply circuit of the electrode of the distribution cabinet is also provided with a temperature-based power control component, and the power control component includes a shell and an end cover fixed to the end face of the shell, the inner wall of the shell is fixed with an iron core, and the outer wall of the iron core is wound with a group of primary coils and multiple groups of secondary coils, the inner wall of the end cover is slidably connected with a slider, and the side wall of the slider is fixed with a sliding contact that contacts with the secondary coil and is electrically conductive, the outer wall of the end cover is rotatably connected with a rotating frame, the inner wall of the rotating frame is provided with a strip groove, and the outer wall of the slider is fixed with a limit column that cooperates with the strip groove.

[0013] As a preferred embodiment of the present invention: the primary coil is electrically connected to the input end of the power distribution cabinet, and one end of the secondary coil and the sliding contact are electrically connected to the input end of the electrode.

[0014] At the same time, a sleeve is fixed to the end side wall of the rotating frame, a cylinder body is fixed to the inner wall of the shell, a piston is slidably connected to the inner wall of the cylinder body, a piston rod is fixed to the top outer wall of the piston, a spiral groove is opened on the inner wall of the sleeve, and a limit column 2 is fixed to the outer wall of the piston rod for movable contact and limit cooperation with the spiral groove.

[0015] As a more preferred solution of the present invention: the cylinder body and the inner cavity are connected to the inner cavity of the hollow piston.

[0016] The beneficial effects of the present invention are: 1. The present invention, by providing a sealing frame, a curved flexible pad, a sealing cavity and other components, can make the electrode and the furnace cover relatively adjustable in insertion depth, and can also achieve overall sealing through the end face sealing pad and the flexible sealing ring pad to prevent leakage, and the fitting pressure of the flexible sealing ring pad is affected by the sealing state, and it automatically fits and seals in the sealing state, and automatically contacts the strong sealing state in the non-working state, which is convenient for adjusting the fixing point of the electrode and the secondary adjustment frame.

[0017] 2. In the present invention, the cavity interlayer can prevent the heat in the furnace body from leaking out to a certain extent, thereby ensuring the internal heating efficiency. At the same time, even if there is waste heat leaking out through the cavity interlayer, the waste heat will be transferred to the water-cooled wall, and then connected to the channel of the heat exchanger through the water-cooled wall, and the heat will be transferred to the heat exchange medium by using the heat exchange medium, and then the circulating water in another channel of the heat exchanger exchanges heat with the heat exchange medium, and the circulating water is heated to form hot water, so that the waste heat can be recycled.

[0018] 3. The present invention, through clever circuit coordination and utilizing the correlation between the position of the cavity piston and the negative pressure, can automatically control the closing of the negative pressure pump and the starting of the electrode, simplifying the control logic, and also avoiding the smelting oxidation caused by the early starting of the electrode before the vacuum state is reached when the negative pressure pump and the electrode are independently controlled, thereby improving the smelting quality.

[0019] 4. The present invention, by setting a temperature-based power control component, can make the starting power of the electrode smaller and reduce the grid load at the moment of starting. At the same time, as the smelting progresses, the power of the electrode increases until it reaches the rated power, and the entire process is automatically regulated using the transformer principle. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the overall structure of an electric arc furnace for waste heat utilization proposed by the present invention; Figure 2 A schematic diagram of the internal structure of a sealing frame of a waste heat utilization electric arc furnace proposed by the present invention; Figure 3 This is a cross-sectional structural diagram of a sealing frame and an electrode matching of a waste heat utilization electric arc furnace proposed by the present invention; Figure 4 A schematic diagram of the connection structure between the support legs and the furnace body of a waste heat utilization electric arc furnace proposed by the present invention; Figure 5 A schematic diagram of the furnace structure of a waste heat utilization electric arc furnace proposed by the present invention; Figure 6 This is a schematic cross-sectional structure diagram of a circuit control part of a waste heat utilization electric arc furnace proposed by the present invention; Figure 7 This is a schematic diagram of the separation structure of a power control component of a waste heat utilization electric arc furnace proposed by the present invention; Figure 8 This is a partial cross-sectional structural schematic diagram of a power control component of a waste heat utilization electric arc furnace proposed by the present invention; Fig. 9 This is a schematic diagram of the circuit structure of a waste heat utilization electric arc furnace proposed by the present invention.

[0021] In the figure: 1, support leg; 2, furnace body; 3, negative pressure pump; 4, furnace cover; 5, sealing frame; 6, electrode; 7, secondary adjustment frame; 8, power distribution cabinet; 9, lifting frame; 10, end face sealing pad; 11, elastic member; 12, curved surface flexible pad; 13, connecting cavity; 14, sealing cavity 1; 15, flexible sealing ring pad; 16, sealing cavity 2; 17, rotating shaft; 18, connecting rod; 19, telescopic rod; 20, cavity interlayer; 21, water-cooled wall; 22, limit ring 1; 23, cylinder barrel; 24, elastic member Spring one; 25, arc head limit rod; 26, limit ring two; 27, electrode half ring; 28, electrode ring; 29, spring two; 30, cavity piston; 31, rotating frame; 32, end cover; 33, limit column one; 34, strip groove; 35, slider; 36, sliding contact; 37, secondary coil; 38, iron core; 39, primary coil; 40, shell; 41, sleeve; 42, limit column two; 43, piston rod; 44, piston; 45, cylinder body; 46, spiral groove; 47, heat exchanger. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described in detail below in conjunction with specific implementation methods.

[0023] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention. Example

[0024] A waste heat utilization electric arc furnace, such as Figure 1 - Fig. 9 As shown, it includes a furnace body 2, a power distribution cabinet 8, and a lifting frame 9. The furnace body 2 is supported or fixed to the ground by supporting legs 1. The top of the furnace body 2 is equipped with a furnace cover 4. A plurality of electrodes 6 are inserted through the inner wall of the furnace cover 4. A negative pressure pump 3 for exhaust is installed on one side of the furnace cover 4.

[0025] The lifting end of the lifting frame 9 is fixedly connected to the furnace cover 4. In this embodiment, the specific type of the lifting frame 9 is not limited. It can be any one of a screw slider, an electric / pneumatic / hydraulic telescope. Since it is a prior art, this embodiment does not make any creative work on it, so it is not limited.

[0026] The lifting end of the lifting frame 9 is connected to the secondary adjustment frame 7 through a lifting mechanism, and the sealing frame 5 is fixed to the bottom of the secondary adjustment frame 7. Similarly, the specific type of the lifting mechanism is not limited in this embodiment, and it can be any one of a screw slider, an electric / pneumatic / hydraulic telescope. Since it is a prior art, this embodiment does not make any creative work on it, so it is not limited.

[0027] The plurality of electrodes 6 are fixed to the inner wall of the secondary adjustment frame 7 , and the outer wall of the electrode 6 is provided with a sealing frame 5 .

[0028] The sealing frame 5 is fitted with the electrode 6 in a clearance, and a sealing cavity 14 matching the number and position of the electrode 6 is opened on the inner wall of the sealing frame 5, a sealing cavity 2 16 is opened in the middle of the sealing frame 5, a flexible sealing ring gasket 15 fitting the outer surface of the electrode 6 is bonded to the inner wall of the sealing cavity 14, a curved flexible gasket 12 is bonded to the bottom of the sealing cavity 2 16, an elastic member 11 is provided between the curved flexible gasket 12 and the top inner wall of the sealing cavity 2 16, an end face sealing gasket 10 is bonded to the bottom outer wall of the sealing frame 5, and the sealing cavity 2 16 is connected to the sealing cavity 14 through a connecting cavity 13.

[0029] During the non-working process, the curved flexible pad 12 is deformed and opened outward by the elastic force of the elastic member 11. At this time, the gas pressure in the closed space composed of the sealing chamber 2 16, the connecting chamber 13, and the sealing chamber 1 14 is relatively low, so that the flexible sealing ring pad 15 expands outward, and the contact pressure between the flexible sealing ring pad 15 and the electrode 6 is relatively small. At this time, the relative position of the electrode 6 can be adjusted through the fixed point of the electrode 6 and the secondary adjustment frame 7. After the adjustment is completed: pour the scrap steel into the furnace body 2, and then first control the secondary adjustment frame 7 and the furnace cover 4 to descend as a whole through the lifting frame 9 until the furnace cover 4 and the furnace body 2 are matched, and then control the lifting mechanism to lower the secondary adjustment frame 7 and the furnace cover 4. The secondary adjustment frame 7 is controlled to descend alone, and the secondary adjustment frame 7 drives the electrode 6 and the sealing frame 5 to descend synchronously until the arc-surface flexible pad 12 contacts the top of the furnace cover 4, and the arc-surface flexible pad 12 is limited. At this time, the secondary adjustment frame 7 continues to descend, so that the arc-surface flexible pad 12 overcomes the elastic force of the elastic member 11 and shrinks inward, so that the pressure of the closed space composed of the end face sealing pad 10, the connecting cavity 13, and the sealing cavity 14 increases, and the flexible sealing ring gasket 15 is pressed inward and tightly fits against the outer wall of the electrode 6, so as to realize the gap sealing between the electrode 6 and the sealing frame 5, and then at this time, the end face sealing pad 10 is tightly fitted with the furnace cover 4 to realize the end face sealing.

[0030] The device, by providing the sealing frame 5, the curved flexible pad 12, the sealing cavity 14 and other components, can make the electrode 6 and the furnace cover 4 relatively adjustable in insertion depth, and can also achieve overall sealing through the end face sealing pad 10 and the flexible sealing ring pad 15 to prevent leakage, and the fitting pressure of the flexible sealing ring pad 15 is affected by the sealing state, and it automatically fits and seals in the sealing state, and automatically contacts the strong sealing state in the non-working state, which is convenient for adjusting the fixing points of the electrode 6 and the secondary adjustment frame 7.

[0031] That is, the adjustment process of the present application can be as follows: during normal use, the lifting mechanism is in a locked state, at which time the sealing frame 5 and the furnace cover 4 are tightly fitted to ensure a sealed state. When the position of the electrode 6 needs to be adjusted, the secondary adjustment frame 7 can be driven to rise by the lifting mechanism, so that the contact pressure between the flexible sealing ring pad 15 and the electrode 6 is reduced. At this time, the fixed point of the electrode 6 and the secondary adjustment frame 7 can be changed to axially adjust the position of the electrode 6, that is, the insertion depth of the electrode 6. After the adjustment is completed, the secondary adjustment frame 7 is controlled to descend by the lifting mechanism, so that the sealing frame 5 and the furnace cover 4 are tightly fitted to ensure a sealed state.

[0032] To solve the dumping problem; Figure 4 As shown, a discharge valve is provided on one side of the furnace body 2, and the two supporting legs 1 located on the discharge valve side are rotatably connected to the furnace body 2 through a rotating shaft 17, and a telescopic rod 19 is provided on the inner wall of the supporting leg 1 away from the discharge valve side, and the telescopic end of the telescopic rod 19 is rotatably connected to a connecting rod 18, and the other end of the connecting rod 18 is rotatably connected to the outer wall of the furnace body 2.

[0033] After the smelting is finished, the telescopic rod 19 can be extended to make the furnace body 2 tilt toward one side of the discharge valve, and then the discharge valve can be opened to discharge.

[0034] In order to solve the problem of waste heat recovery; Figure 5 As shown, the furnace body 2 has a cavity interlayer 20, which is in a vacuum state, and a water-cooled wall 21 is fixed to the outer wall of the furnace body 2, and a heat exchanger 47 is fixed to the outer wall of the furnace body 2. The heat exchanger 47 is a double-channel heat exchanger, and one channel of the heat exchanger 47 is respectively connected to the two ends of the water-cooled wall 21, and the other channel of the heat exchanger 47 can be connected to a circulating water system.

[0035] The cavity interlayer 20 can prevent the heat in the furnace body 2 from leaking out to a certain extent, thereby ensuring the internal heating efficiency. At the same time, even if waste heat leaks out through the cavity interlayer 20, the waste heat will be transferred to the water-cooled wall 21, and then connected to the channel of the heat exchanger 47 through the water-cooled wall 21, and the heat will be transferred to the heat exchange medium by using the heat exchange medium, and then the circulating water in another channel of the heat exchanger 47 will exchange heat with the heat exchange medium, and the circulating water will be heated to form hot water, so that the waste heat can be recycled.

[0036] To solve control problems; such as Figure 6 As shown, a cylinder 23 is welded to one side of the furnace cover 4, and a limit ring 1 22 and a limit ring 26 are respectively fixed on both sides of the inner wall of the cylinder 23, and the inner wall of the cylinder 23 located between the limit ring 1 22 and the limit ring 26 is slidably connected with a cavity piston 30, and the side wall of the cylinder 23 is connected to an arc head limit rod 25 for limiting the movement of the cavity piston 30 through a spring 1 24, and a spring 29 is buckled on one side of the limit ring 1 22, and the other end of the spring 29 is buckled to the side wall of the cavity piston 30.

[0037] A pair of electrode half rings 27 are fixed to the side wall of the second limiting ring 26, and another pair of electrode half rings 27 are fixed to the outer wall of the cavity piston 30 located on one side of the electrode half ring 27. The two pairs of electrode half rings 27 cooperate with each other and are connected in series in the power supply circuit of the negative pressure pump 3 of the distribution cabinet 8.

[0038] A pair of electrode rings 28 are fixed to the side wall of the limiting ring 22, and another pair of electrode rings 28 are fixed to the outer wall of the cavity piston 30 on one side of the electrode half ring 27. The two pairs of electrode rings 28 cooperate with each other and are connected in series in the power supply circuit of the electrode 6 of the distribution cabinet 8.

[0039] When in the non-working state, the furnace cover 4 is separated from the furnace body 2, and there is no negative pressure. At this time, the cavity piston 30 is acted upon by the elastic force of the spring 29 and is located based on Figure 6The left side position of the two pairs of electrode half rings 27 are in contact with each other, and the negative pressure pump 3 can be controlled to start. When the furnace cover 4 cooperates with the furnace body 2, the negative pressure pump 3 is controlled to start vacuuming, and the pressure in the closed space composed of the furnace cover 4 and the furnace body 2 gradually decreases, so that the cavity piston 30 is subjected to negative pressure attraction. Until the required vacuum state is reached, the negative pressure attraction exerted on the cavity piston 30 is greater than the elastic resistance of the arc head limit rod 25 to the cavity piston 30, and the cavity piston 30 instantly moves to the right side, so that the electrode half rings 27 are separated, and the electrode rings 28 are in contact and cooperate, the negative pressure pump 3 is automatically closed, and the electrode 6 is started for heating until the smelting is completed. The lifting frame 9 controls the furnace body 2 to separate from the furnace cover 4, and the negative pressure disappears. At this time, the cavity piston 30 is subjected to the elastic force of the spring 29 and is located based on Figure 6 In the left position, electrode 6 is disconnected.

[0040] The device, through clever circuit coordination and utilizing the correlation between the position of the cavity piston 30 and the negative pressure, can automatically control the closing of the negative pressure pump 3 and the starting of the electrode 6, simplifying the control logic, and also avoiding the smelting oxidation caused by the early starting of the electrode 6 before the vacuum state is reached when the negative pressure pump 3 and the electrode 6 are independently controlled, thereby improving the smelting quality.

[0041] When the present embodiment is in use, when the position of the electrode 6 needs to be adjusted, the secondary adjustment frame 7 can be driven to rise by the lifting mechanism, so that the contact pressure between the flexible sealing ring pad 15 and the electrode 6 is reduced. At this time, the fixing point of the electrode 6 and the secondary adjustment frame 7 can be changed to axially adjust the position of the electrode 6, that is, the insertion depth of the electrode 6. After the adjustment is completed, the secondary adjustment frame 7 is controlled to descend by the lifting mechanism, so that the sealing frame 5 and the furnace cover 4 are tightly fitted to ensure the sealing state. Then, the furnace cover 4 is separated from the furnace body 2 by controlling the lifting frame 9, and the scrap steel is poured into the furnace body 2. Then, the furnace cover 4 is combined with the furnace body 2 by controlling the lifting frame 9, and the negative pressure pump 3 is started to negatively The pressure in the closed space formed by the furnace cover 4 and the furnace body 2 is gradually reduced, so that the cavity piston 30 is subjected to negative pressure attraction, until the required vacuum state is reached, the negative pressure attraction of the cavity piston 30 is greater than the elastic resistance of the arc head limit rod 25 to the cavity piston 30, and the cavity piston 30 instantly moves to the right side, so that the electrode half ring 27 is separated, and the electrode ring 28 is in contact and matched, the negative pressure pump 3 is automatically closed, and the electrode 6 is started to heat until it is completely melted, and the lifting frame 9 controls the furnace body 2 to separate from the furnace cover 4. At this time, the negative pressure on the cavity piston 30 disappears, and at this time, the cavity piston 30 is subjected to the elastic force of the spring 29, and is located based on Figure 6 The electrode 6 is disconnected, and then the telescopic rod 19 is extended to make the furnace body 2 tilt toward the side of the discharge valve, and then the discharge valve is opened to discharge. Example

[0042] A waste heat utilization electric arc furnace, such as Figure 1 - Fig. 9 As shown, in order to solve the control problem of smelting power and smelting temperature, this embodiment makes the following improvements on the basis of embodiment 1: the power supply circuit of the electrode 6 of the power distribution cabinet 8 is also provided with a temperature-based power control component.

[0043] The power control component includes a shell 40 and an end cover 32 fixed to the end face of the shell 40, the inner wall of the shell 40 is fixed with an iron core 38, the outer wall of the iron core 38 is wound with a group of primary coils 39 and multiple groups of secondary coils 37, the inner wall of the end cover 32 is slidably connected with a slider 35, and the side wall of the slider 35 is fixed with a sliding contact 36 that contacts and electrically conducts with the secondary coil 37.

[0044] The primary coil 39 is electrically connected to the input end of the power distribution cabinet 8 , and one end of the secondary coil 37 and the sliding contact 36 are electrically connected to the input end of the electrode 6 .

[0045] The outer wall of the end cover 32 is rotatably connected to the rotating frame 31 , the inner wall of the rotating frame 31 is provided with a strip groove 34 , and the outer wall of the sliding block 35 is fixed with a limiting column 33 which is limitedly matched with the strip groove 34 .

[0046] A sleeve 41 is fixed to the end face side wall of the rotating frame 31, a cylinder body 45 is fixed to the inner wall of the shell 40, a piston 44 is slidably connected to the inner wall of the cylinder body 45, a piston rod 43 is fixed to the top outer wall of the piston 44, a spiral groove 46 is formed on the inner wall of the sleeve 41, and a limiting column 42 is fixed to the outer wall of the piston rod 43 which is movably contacted and limitedly matched with the spiral groove 46.

[0047] The cylinder body 45 and the inner cavity are communicated with the inner cavity of the cavity piston 30 .

[0048] When this embodiment is in use, when the distribution cabinet 8 inputs alternating current to the primary coil 39, an induced magnetic field is generated in the iron core 38, thereby generating an induced voltage in the secondary coil 37 and applying it to the electrode 6, and the electrode 6 undergoes arc melting. As the electrode 6 melts, the temperature in the furnace body 2 gradually increases, thereby increasing the temperature of the inner cavity of the cavity piston 30. The gas in the inner cavity of the cavity piston 30 expands due to heat, and the pressure increases. The pressure is transmitted to the inner cavity of the cylinder body 45, and the piston 44 moves due to the pressure, thereby driving the sleeve 41 to rotate through the limiting column 42, so that the rotating frame 31 rotates, and the rotating frame 31 drives the slider 35 to slide through the strip groove 34 and the limiting column 33, so that the contact position of the sliding contact 36 and the secondary coil 37 changes, thereby changing the number of connected turns of the secondary coil 37, so that the number of connected turns of the secondary coil 37 gradually increases with the increase of temperature.

[0049] This device, by setting a temperature-based power control component, can make the starting power of the electrode 6 smaller, reduce the grid load at the moment of starting, and at the same time, with the smelting, the power of the electrode 6 increases until it reaches the rated power, and the whole process is automatically regulated using the transformer principle.

[0050] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An electric arc furnace for waste heat utilization, comprising a furnace body (2), a power distribution cabinet (8), and a lifting frame (9), wherein the furnace body (2) is supported or fixed to the ground by supporting legs (1), a furnace cover (4) is provided on the top of the furnace body (2), a plurality of electrodes (6) are inserted through the inner wall of the furnace cover (4), and a negative pressure pump (3) for exhaust is installed on one side of the furnace cover (4), characterized in that: The lifting end of the lifting frame (9) is fixedly connected to the furnace cover (4), and the lifting end of the lifting frame (9) is connected to the secondary adjustment frame (7) through a lifting mechanism. The plurality of electrodes (6) are fixed to the inner wall of the secondary adjustment frame (7), and the outer wall of the electrode (6) is provided with a sealing frame (5), and the sealing frame (5) is fixed to the bottom of the secondary adjustment frame (7); The sealing frame (5) and the electrode (6) are gap-matched, and the inner wall of the sealing frame (5) is provided with a sealing cavity (14) matching the number and position of the electrodes (6), and the middle part of the sealing frame (5) is provided with a sealing cavity (16), and the inner wall of the sealing cavity (14) is bonded with a flexible sealing ring gasket (15) that fits the outer surface of the electrode (6), and the bottom of the sealing cavity (16) is bonded with a curved flexible gasket (12), and the curved flexible gasket (12) and the top inner wall of the sealing cavity (16) are provided with an elastic member (11), and the bottom outer wall of the sealing frame (5) is bonded with an end face sealing gasket (10), and the sealing cavity (16) and the sealing cavity (14) are connected through a connecting cavity (13).

2. The waste heat utilization electric arc furnace according to claim 1, characterized in that: A discharge valve is provided on one side of the furnace body (2); two support legs (1) located on the discharge valve side are rotatably connected to the furnace body (2) via a rotating shaft (17); a telescopic rod (19) is provided on the inner wall of the support leg (1) away from the discharge valve side; the telescopic end of the telescopic rod (19) is rotatably connected to a connecting rod (18); the other end of the connecting rod (18) is rotatably connected to the outer wall of the furnace body (2).

3. The waste heat utilization electric arc furnace according to claim 1, characterized in that: The furnace body (2) has a cavity interlayer (20), the cavity interlayer (20) is in a vacuum state, and a water-cooled wall (21) is fixed to the outer wall of the furnace body (2), and a heat exchanger (47) is fixed to the outer wall of the furnace body (2), and the heat exchanger (47) is a double-channel heat exchanger, one channel of the heat exchanger (47) is respectively connected to two ends of the water-cooled wall (21), and the other channel of the heat exchanger (47) is connected to a circulating water system.

4. The waste heat utilization electric arc furnace according to claim 1, characterized in that: A cylinder (23) is welded to one side of the furnace cover (4), and a limiting ring 1 (22) and a limiting ring 2 (26) are fixed to both sides of the inner wall of the cylinder (23), and a cavity piston (30) is slidably connected to the inner wall of the cylinder (23) located between the limiting ring 1 (22) and the limiting ring 2 (26), and the side wall of the cylinder (23) is connected to an arc-shaped limiting rod (25) for limiting the movement of the cavity piston (30) via a spring 1 (24), and a spring 2 (29) is buckled to one side of the limiting ring 1 (22), and the other end of the spring 2 (29) is buckled to the side wall of the cavity piston (30).

5. The waste heat utilization electric arc furnace according to claim 4, characterized in that: A pair of electrode half rings (27) is fixed to the side wall of the second limiting ring (26), and another pair of electrode half rings (27) is fixed to the outer wall of the cavity piston (30) located on one side of the electrode half ring (27). The two pairs of electrode half rings (27) cooperate with each other and are connected in series to the power supply circuit of the negative pressure pump (3) of the power distribution cabinet (8).

6. The waste heat utilization electric arc furnace according to claim 5, characterized in that: A pair of electrode rings (28) is fixed to the side wall of the first limiting ring (22), and another pair of electrode rings (28) is fixed to the outer wall of the cavity piston (30) located on one side of the electrode half ring (27). The two pairs of electrode rings (28) cooperate with each other and are connected in series in the power supply circuit of the pair of electrodes (6) of the power distribution cabinet (8).

7. The waste heat utilization electric arc furnace according to claim 4, characterized in that: The power distribution cabinet (8) is also provided with a temperature-based power control component for the power supply circuit of the electrode (6), the power control component comprising a shell (40) and an end cover (32) fixed to the end face of the shell (40), an iron core (38) fixed to the inner wall of the shell (40), a group of primary coils (39) and a plurality of groups of secondary coils (37) wound around the outer wall of the iron core (38), a slider (35) slidably connected to the inner wall of the end cover (32), a sliding contact (36) in contact with and electrically conductive with the secondary coil (37) fixed to the side wall of the slider (35), a rotating frame (31) rotatably connected to the outer wall of the end cover (32), a strip groove (34) opened on the inner wall of the rotating frame (31), and a limiting column (33) that is limited and matched with the strip groove (34) fixed to the outer wall of the slider (35).

8. The waste heat utilization electric arc furnace according to claim 7, characterized in that: The primary coil (39) is electrically connected to the input end of the power distribution cabinet (8), and one end of the secondary coil (37) and the sliding contact (36) are electrically connected to the input end of the electrode (6).

9. The waste heat utilization electric arc furnace according to claim 7, characterized in that: A sleeve (41) is fixed to the side wall of the end face of the rotating frame (31), a cylinder body (45) is fixed to the inner wall of the housing (40), a piston (44) is slidably connected to the inner wall of the cylinder body (45), a piston rod (43) is fixed to the top outer wall of the piston (44), a spiral groove (46) is formed on the inner wall of the sleeve (41), and a second limiting column (42) that is movably contacted and limitedly matched with the spiral groove (46) is fixed to the outer wall of the piston rod (43).

10. The waste heat utilization electric arc furnace according to claim 9, characterized in that: The cylinder body (45) and the inner cavity are in communication with the inner cavity of the hollow piston (30).

Images