CN217131782U - Electric arc furnace heat shielding device and electric arc furnace - Google Patents

Abstract

The utility model discloses an electric arc furnace hides heat facility and electric arc furnace relates to crucible production facility technical field, under the condition of effectively solving apron melting, softening and fracture problem, prolongs the life of apron and crucible. The electric arc furnace heat shielding device comprises a heat shielding plate, a cover plate and a cooling assembly, and a first through hole is formed in the heat shielding plate in a penetrating mode. The cover plate is arranged on one surface, far away from the electric arc furnace, of the heat shield plate, and a second through hole is formed in the cover plate in a penetrating mode. The cooling assembly is arranged on one surface, far away from the heat shield, of the cover plate, a third through hole is formed in the cooling assembly in a penetrating mode, and the cooling assembly is used for cooling the cover plate. The first through hole, the second through hole and the third through hole are communicated. The electric arc furnace comprises a furnace body, an electrode and the electric arc furnace heat shielding device, the electric arc furnace heat shielding device is arranged on the furnace body, and a first through hole, a second through hole and a third through hole which are formed in the electric arc furnace heat shielding device are communicated to form a through hole used for accommodating the electrode to move.

Description

Electric arc furnace heat shielding device and electric arc furnace

Technical Field

The utility model relates to a crucible production facility technical field especially relates to an electric arc furnace hides heat facility and electric arc furnace.

Background

The electric arc furnace melts the quartz sand by generating a high-temperature electric arc through a graphite electrode to produce a quartz crucible. In order to avoid the quick loss of heat and prevent that high temperature arc radiation from causing the injury to the main equipment to prevent that dust etc. from falling to the crucible, be provided with the heat shield on the electric arc furnace. The heat shield is a hollow structure with a round hole in the center, self heat is taken away through a circulating water path, and the electrode penetrates through the round hole in the center. Because the arc temperature is extremely high (the core temperature is above 5000 ℃), if the diameter of the central circular hole is smaller, the high temperature causes the welding opening of the heat shield close to the arc to age, the phenomena of cracking and water leakage occur, and the crucible is scrapped. Moreover, when the central round hole is too small, the peripheral wall of the central round hole is easy to be hit by electric arcs, so that metal at the hit position of the heat shield is collapsed into the crucible, and the crucible is subjected to black spot defect. The main component of the black spot is iron element, which can seriously affect the crystal pulling quality in the crystal pulling process and can cause the problems of crystallization of a crucible and the like. And when the central round hole is larger, the heat shield plate can not effectively play the roles of avoiding the rapid loss of heat and preventing dust from falling into the crucible.

In the prior art, a quartz plate with a central opening is usually arranged on a heat shield plate, and the diameter of the central opening of the quartz plate is smaller than that of a central circular hole of the heat shield plate. The quartz plate can resist the high temperature of 1700 ℃, and the quartz is a mineral composed of insulating material silicon dioxide and is not easy to hit by electric arc, so that the problem is relieved.

The provision of quartz plates entails other technical problems. For example, because the temperature of the electric arc is high, the quartz plate close to the electric arc is melted after continuous use, and the melted quartz drops fall into the crucible, so that the crucible is raised. In addition, the continuous high temperature can soften and deform the quartz plate, so that the quartz plate cannot be used continuously, and the service life of the quartz plate is shortened. At the moment of arc striking, the inner edge of the quartz plate is rapidly heated, and a great temperature difference is formed between the inner edge and the outer edge, so that the quartz plate is easy to crack, cracked fragments can fall into the crucible, and the service life of the crucible is shortened.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an electric arc furnace hides heat facility and electric arc furnace, under the condition of effectively solving apron melting, softening and fracture problem, prolongs the life of apron and crucible.

In order to achieve the above object, in a first aspect, the present invention provides an electric arc furnace heat shield, which comprises a heat shield, a cover plate and a cooling assembly, wherein a first through hole is formed through the heat shield. The cover plate is arranged on one surface, far away from the electric arc furnace, of the heat shield plate, and a second through hole is formed in the cover plate in a penetrating mode. The cooling assembly is arranged on one surface, far away from the heat shield, of the cover plate, a third through hole is formed in the cooling assembly in a penetrating mode, and the cooling assembly is used for cooling the cover plate. The first through hole, the second through hole and the third through hole are communicated.

When the technical scheme is adopted, the heat shield plate penetrates through the heat shield plate to be provided with the first through hole, the cover plate penetrates through the heat shield plate to be provided with the second through hole, the cooling assembly penetrates through the cover plate to be provided with the third through hole, and the first through hole, the second through hole and the third through hole are communicated. During practical application, one end of the electrode sequentially penetrates through the communicated third through hole, the second through hole and the first through hole, and the quartz sand is melted at high temperature. The cooling assembly is arranged on one surface, far away from the heat shield, of the cover plate and used for cooling the cover plate. The working temperature of the cover plate is reduced, the problems of melting, softening and cracking of the cover plate at high temperature are effectively solved, liquid generated by melting the cover plate and fragments formed by cracking of the cover plate are prevented from falling into the crucible, the service life of the cover plate is prolonged, and the service life of the crucible is prolonged.

In one possible implementation, the cover plate is a graphite-carbon fiber composite cover plate.

When the technical scheme is adopted, the graphite-carbon fiber composite material has the advantages of high strength, thermal shock resistance, and no cracking due to rapid cooling and rapid heating. The graphite-carbon fiber composite cover plate is not easy to melt, soften and crack, so that the situation that liquid generated by melting the cover plate and fragments formed by cracking the cover plate fall into a crucible is avoided, the service lives of the cover plate and the crucible are prolonged, and the use cost is reduced.

In a possible implementation manner, the cooling assembly comprises a cooling plate and at least two water service pipes, wherein the cooling plate is internally provided with a containing cavity, and the water service pipes are communicated with the containing cavity.

When the technical scheme is adopted, the cooling plate is internally provided with the containing cavity so as to form a water storage space. The water service pipe is communicated with the accommodating cavity, so that cooling water can be conveniently injected into the accommodating cavity through the water service pipe. The quantity of water service pipe is two at least to set up inlet tube and outlet pipe, inlet tube, outlet pipe and holding chamber form the water return circuit. The heat of cooling plate is walked to the cooling water that flows for the temperature of cooling plate reduces, further reduces the temperature with the apron of cooling plate contact, thereby keeps the temperature of apron below certain temperature range, avoids appearing the apron and melts the condition that the liquid that produces and the piece that the apron fracture formed fall into the crucible, is favorable to prolonging the life of apron and crucible, reduces use cost.

In a possible implementation manner, the number of the water service pipes is two, and the two water service pipes are respectively a water inlet pipe and a water outlet pipe.

In a possible realization, a partition is provided in the cooling plate, which partition is used to disconnect the accommodation chamber. The water inlet pipe and the water outlet pipe are respectively arranged at two ends of the accommodating cavity.

When the technical scheme is adopted, the cooling water flows in from one end of the accommodating cavity and flows out from the other end of the accommodating cavity, so that the cooling water is fully used, and the cooling plate is fully cooled.

In one possible implementation, the first through hole, the second through hole and the third through hole are coaxial.

When the technical scheme is adopted, the first through hole and the second through hole are coaxially arranged, and the electrode extends into the electric arc furnace along the central axis shared by the first through hole and the second through hole, so that the cover plate and the heat shield plate are uniformly heated by the electrode. The situation that the cover plate and the heat shield plate are damaged due to the fact that the electrode is too close to one side of the cover plate and the heat shield plate at high temperature is avoided. The third through hole is coaxial with the first through hole and the second through hole, so that the cover plate is uniformly cooled by cooling water, the phenomenon that the cover plate is cracked due to large temperature difference is avoided, the service life of the cover plate is prolonged, and consumables are saved.

In one possible implementation, the diameter of the first through hole is defined as D1, the diameter of the second through hole is defined as D2, and the diameter of the third through hole is defined as D3, D1 > D3 > D2.

When the technical scheme is adopted, D1 is larger than D2, and the effect of preventing dust and the like from falling into the crucible can be better achieved. And D3 > D2, not only avoid cooling module to be too close to the electrode, cause the phenomenon of cooling module damage, make cooling module can be comparatively effectual carry out cooling to the apron moreover.

In one possible embodiment, the cover plate has a surface facing away from the heat shield plate, which is provided with a recess corresponding to the cooling plate, for receiving the cooling plate.

When the technical scheme is adopted, the cooling plate is arranged in the groove of the cover plate, the contact area of the cover plate and the cooling plate is increased, and the cooling function of the cooling plate on the cover plate can be realized to the greatest extent. Moreover, the cooling plate sets up in the recess that the apron has, has strengthened the structural integrity and the stability of device, effectively reduces the probability that the cooling plate slided from the apron.

In one possible implementation, the cover plate has a planar structure on a surface away from the heat shield.

When the technical scheme is adopted, the cover plate is provided with the surface far away from the heat shield plate, so that the cover plate can be conveniently machined, and the machining period of the device is saved.

In a second aspect, the present invention further provides an electric arc furnace, which comprises a furnace body, an electrode, and the electric arc furnace heat shielding device described in the first aspect or any possible implementation manner of the first aspect, wherein the electric arc furnace heat shielding device is disposed on the furnace body, and the electric arc furnace heat shielding device has a first through hole, a second through hole, and a third through hole communicated with each other to form a through hole for accommodating the movement of the electrode.

Compared with the prior art, the utility model provides an electric arc furnace's beneficial effect is the same with the electric arc furnace that first aspect or any possible implementation mode of first aspect described hides hot device's beneficial effect, and the no description is done here.

Drawings

The accompanying drawings, which are described herein, serve to provide a further understanding of the invention and constitute a part of this specification, and the exemplary embodiments and descriptions thereof are provided for explaining the invention without unduly limiting it. In the drawings:

fig. 1 is a schematic structural diagram of a heat shielding device of an electric arc furnace according to an embodiment of the present invention;

fig. 2 is a schematic front view of an electric arc furnace heat shielding device according to an embodiment of the present invention;

FIG. 3 is a schematic cross-sectional view taken along line A-A of FIG. 2;

fig. 4 is a schematic bottom view of an electric arc furnace heat shielding device according to an embodiment of the present invention;

fig. 5 is a schematic cross-sectional view of a cooling plate according to an embodiment of the present invention.

Reference numerals:

1-heat shield, 2-cover plate, 31-cooling plate,

32-partition board, 33-water pipe, 331-water inlet pipe,

332-water outlet pipe.

Detailed Description

In order to make the technical problem, technical solution and beneficial effects to be solved by the present invention more clearly understood, the following description is made in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise. The meaning of "a number" is one or more unless specifically limited otherwise.

In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", and the like indicate orientations or positional relationships based on orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected" and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

The utility model provides an electric arc furnace heat-insulation device, as shown in fig. 1 to 4, electric arc furnace heat-insulation device includes heat-insulation plate 1, apron 2 and cooling module, runs through heat-insulation plate 1 and sets up first through-hole. The cover plate 2 is arranged on one surface of the heat shield plate 1, which is far away from the electric arc furnace, and a second through hole is formed through the cover plate 2. The cooling assembly is arranged on one surface, away from the heat shield plate 1, of the cover plate 2, a third through hole is formed in the cooling assembly in a penetrating mode, and the cooling assembly is used for cooling the cover plate 2. The first through hole, the second through hole and the third through hole are communicated.

Referring to fig. 1 and 3, a first through hole is formed through the heat shield plate 1, a second through hole is formed through the cover plate 2, a third through hole is formed through the cooling module, and the first through hole, the second through hole and the third through hole are communicated with each other. During practical application, one end of the electrode sequentially penetrates through the communicated third through hole, the second through hole and the first through hole, and the quartz sand is melted at high temperature. The cooling unit is disposed on a side of the cover plate 2 away from the heat shield plate 1, and is used for cooling the cover plate 2. Make the operating temperature of apron 2 reduce to keep in certain temperature range, effectively solve apron 2 and take place the problem of melting, softening and fracture under high temperature, avoid apron 2 to melt the liquid of production and the piece that the 2 ftractures of apron formed and fall into the crucible, not only prolonged apron 2's life, practiced thrift apron 2's input cost, reduce the spending, prevent moreover that the crucible from shortening the life of crucible because of sneaking into impurity.

During specific implementation, a cavity is arranged in the heat shield plate 1, and cooling water which flows circularly is arranged in the cavity. The heat of heat shield 1 is taken away through the cooling water that sets up the circulation flow for cooling heat shield 1, preventing 1 high temperature of heat shield, the ageing phenomenon appears, leads to leaking, and in water fell into the crucible, make the crucible scrap. The shape of the heat shield 1 is set according to actual conditions, and is not specifically limited here, and the embodiment of the present invention provides a heat shield 1 having a square structure, as shown in fig. 1 and 2. In addition, in order to improve the strength of the heat shield plate 1, prolong the service life of the heat shield plate 1, and prevent the heat shield plate 1 from corroding and rusting, the heat shield plate 1 is usually made of stainless steel, such as 304 stainless steel, 310S stainless steel, 316L stainless steel, and the like, and is specifically selected according to actual conditions, which is only an example and is not limited specifically.

It should be understood that the cover plate 2 is arranged on the side of the heat shield plate 1 far away from the electric arc furnace, and when the cover plate 2 is cooled, the heat of the heat shield plate 1 is taken away, so that the temperature of the heat shield plate 1 is reduced, the heat shield plate 1 is further cooled, and the phenomenon of aging and water leakage caused by overhigh temperature of the heat shield plate 1 is prevented.

As a possible implementation, the cover plate 2 is a graphite-carbon fiber composite cover plate. The graphite-carbon fiber composite material has the advantages of high strength, thermal shock resistance, and no cracking due to rapid cooling and rapid heating. During practical application, compare in current quartz material apron, the embodiment of the utility model provides a graphite-carbon fiber composite apron is difficult for appearing melting, softening, the fracture problem, effectively avoids because apron 2 the condition that the piece that melts the liquid that produces and apron 2 fracture formation appears falls into the crucible, has reduced the harmfulness that quartz cover plate caused, and graphite-carbon fiber composite apron life promotes than quartz cover plate by a wide margin, is favorable to prolonging the life of apron and crucible, reduces use cost.

In specific implementation, the cover plate 2 may also be a carbon fiber toughened composite ceramic cover plate, such as an alumina-carbon fiber composite cover plate, a silica-carbon fiber composite cover plate, or the like. Apron 2 can be split type apron or integral type apron, and each component of split type apron can exist independently, and when the access & exit of work place was less or there was crooked passageway, can carry respectively to the work place with each component of 2 components of apron that set up separately, later assemble again to satisfy actual need. In this case, the applicable range of the heat shield device can be expanded. The integral cover plate can be assembled without the need of assembling the integral cover plate, so that errors during assembling are reduced or eliminated, adjusting time is saved, and working efficiency is improved. In the embodiment provided by the present invention, as shown in fig. 1 and fig. 2, the cover plate 2 is formed by splicing two square plates. Apron 2 can directly place on heat shield 1, sets up many reference columns on heat shield 1, and apron 2 places in the accommodation space that the reference column formed. The cover plate 2 can also be connected with the heat shield plate 1 by means of welding connection, so as to enhance the stability of the cover plate 2. The dimensions of the heat shield plate 1 and the cover plate 2 are set according to the actual situation and are not particularly limited herein. The outer edge of the cover plate 2 is larger than the outer diameter of the first through hole of the heat shield plate 1, so that the outer contour of the cover plate 2 is ensured to be enough to cover the first through hole of the heat shield plate 1, the cover plate 2 can be placed on the heat shield plate 1, and the function of preventing dust from falling into a crucible can be achieved.

As shown in fig. 1 and 2, the cooling module includes a cooling plate 31 and at least two water pipes 33, and the cooling plate 31 has a receiving cavity therein to form a water storage space. The water pipe 33 is communicated with the accommodating cavity, so that cooling water can be conveniently injected into the accommodating cavity through the water pipe 33. The number of the water pipes 33 is at least two to provide the water inlet pipe 331 and the water outlet pipe 332. The top of the cooling plate 31 is provided with a water through hole corresponding to the water through pipe 33, cooling water enters the accommodating cavity from the water inlet pipe 331 and flows out of the accommodating cavity from the water outlet pipe 332, and the water inlet pipe 331, the water outlet pipe 332 and the accommodating cavity form a water loop. The heat of cooling plate 31 is walked to the cooling water that flows for the temperature of cooling plate 31 reduces, further reduces the temperature with the apron 2 of cooling plate 31 contact, thereby keeps the temperature of apron 2 below certain temperature range, avoids appearing the apron 2 and melts the condition that the liquid that produces and the piece that the apron 2 fracture formed fall into the crucible, is favorable to prolonging the life of apron 2 and crucible, reduces use cost. The embodiment of the utility model provides a cooling module and the cooperation of graphite-carbon fiber composite apron 2, the effect of the cooling to apron 2 of playing that can be fine. Test research shows that the cooling assembly can control the highest temperature of the graphite-carbon fiber cover plate 2 in the using process to be below 700 ℃, the graphite-carbon fiber cover plate 2 is only slightly oxidized under the temperature condition, and the service life of the graphite-carbon fiber cover plate 2 is effectively prolonged.

The material of the cooling unit is set according to the actual situation, and is not particularly limited here. For example, the material may be a metal material such as copper, aluminum, stainless steel, etc., and in the embodiment provided by the present invention, a pure copper material with high thermal conductivity is preferable. So that the cooling water can quickly absorb the heat of the cover plate 2 and the temperature of the cover plate 2 is not too high. During practical application, the embodiment of the utility model provides a cooling module also can use with the cooperation of the quartz material apron 2 among the prior art, can reach and reduce 2 temperatures of quartz apron, reduces the effect of melting, softening.

In some embodiments, the number of the water pipes 33 is two, and the two water pipes 33 are the water inlet pipe 331 and the water outlet pipe 332. As shown in fig. 1 and fig. 2, the functions of the water inlet pipe 331 and the water outlet pipe 332 can be interchanged in practical application. A partition plate 32 is provided in the cooling plate 31, as shown in fig. 5, the partition plate 32 is used for cutting off the accommodating cavity, and the water inlet pipe 331 and the water outlet pipe 332 are respectively provided at two ends of the accommodating cavity. The cooling water flows in from the one end of holding chamber, flows out from the other end of holding chamber, is favorable to making the best use of cooling water, carries out abundant cooling to cooling plate 31, avoids causing the waste of cooling water, reaches best cooling effect.

As a possible implementation, the first through hole, the second through hole and the third through hole are coaxial. The shape of the cooling plate 31 is set according to the actual situation, and is not particularly limited here. In the embodiment of the present invention, the cooling plate 31 has a circular ring structure. Referring to fig. 3, when the first through hole and the second through hole are coaxially arranged, the electrode extends into the arc furnace along a central axis shared by the first through hole and the second through hole, so that the cover plate 2 and the heat shield plate 1 are uniformly heated by the electrode. The situation that the cover plate 2 and the heat shield plate 1 are damaged due to the fact that the electrode is too close to one side of the cover plate 2 and the heat shield plate 1 at high temperature is avoided. The third through-hole sets up with first through-hole, the second through-hole is coaxial, and when the cooling water flowed through cooling plate 31, the route of flowing through of cooling water was located apron 2 and was close to the circumferential position department of electrode, made the cooling water evenly cool off apron 2, avoided apron 2 to be great because of the difference in temperature, and the phenomenon of fracture appears, the life of extension apron 2, the saving consumptive material.

As a possible implementation, referring to fig. 3, the diameter of the first through hole is defined as D1, the diameter of the second through hole is defined as D2, and the diameter of the third through hole is defined as D3. In specific implementation, the diameter D1 of the first through hole, the diameter D2 of the second through hole, and the diameter D3 of the third through hole are set according to actual conditions, and are not specifically limited herein, but D1 > D3 > D2 are satisfied. D1 > D2, when the diameter of first through-hole is greater than the diameter of second through-hole promptly, not only can avoid heat shield 1 to be close apart from the electrode and the phenomenon that easily appears heat shield 1 crater ageing, fracture and leak, can be better play prevent that dust etc. from falling into the effect of crucible moreover. And D3 > D2, the diameter of third through-hole is greater than the diameter of second through-hole promptly, not only avoids cooling module to be too close to the electrode, causes the phenomenon of cooling module damage, makes cooling module can be comparatively effectual carry out cooling to apron 2 moreover.

In one example, as shown in fig. 3, the cover plate 2 has a face remote from the heat shield plate 1 provided with a groove corresponding to the cooling plate 31 for accommodating the cooling plate 31. The cooling plate 31 is arranged in the groove of the cover plate 2, so that the contact area between the cover plate 2 and the cooling plate 31 is increased, and the cooling function of the cooling plate 31 on the cover plate 2 can be realized to the maximum extent. Moreover, the cooling plate 31 is arranged in the groove of the cover plate 2, so that the structural integrity and stability of the device are enhanced, and the probability that the cooling plate 31 slides down from the cover plate 2 is effectively reduced.

In another example, the cover plate 2 has a plane structure on the surface far away from the heat shield plate 1, which facilitates the processing of the cover plate 2 and shortens the processing cycle of the device.

The utility model also provides an electric arc furnace, including furnace body, electrode and foretell electric arc furnace heat-shielding device, electric arc furnace heat-shielding device lid is established on the furnace body, and electric arc furnace heat-shielding device has first through-hole, second through-hole and third through-hole intercommunication and forms the through-hole that is used for holding the electrode removal.

The utility model provides an electric arc furnace's beneficial effect is the same with the electric arc furnace heat shield device's that above-mentioned technical scheme described beneficial effect, and the here is not repeated.

In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (10)

1. An electric arc furnace heat shield, comprising:

the heat shield plate penetrates through the heat shield plate and is provided with a first through hole;

the cover plate is arranged on one surface, away from the electric arc furnace, of the heat shield plate, and a second through hole penetrates through the cover plate;

the cooling assembly is arranged on one surface, far away from the heat shield, of the cover plate, a third through hole is formed through the cooling assembly, and the cooling assembly is used for cooling the cover plate; the first through hole, the second through hole and the third through hole are communicated.

2. The electric arc furnace heat shield of claim 1, wherein the cover plate is a graphite-carbon fiber composite cover plate.

3. The electric arc furnace heat shield apparatus of claim 1, wherein the cooling assembly comprises:

the cooling plate is internally provided with an accommodating cavity;

and the water service pipes are communicated with the accommodating cavity.

4. The electric arc furnace heat shield apparatus of claim 3, wherein said number of water pipes is two, and said two water pipes are a water inlet pipe and a water outlet pipe, respectively.

5. The electric arc furnace heat shield according to claim 4, wherein a partition is provided in the cooling plate for disconnecting the receiving chamber; the water inlet pipe and the water outlet pipe are respectively arranged at two ends of the accommodating cavity.

6. The electric arc furnace heat shield according to claim 1, wherein the first through hole, the second through hole, and the third through hole are coaxial.

7. The electric arc furnace heat shield of claim 6, wherein the diameter of said first through hole is defined as D1, the diameter of said second through hole is defined as D2, the diameter of said third through hole is defined as D3, D1 > D3 > D2.

8. The electric arc furnace heat shield according to claim 3, wherein the cover plate has a surface remote from the heat shield provided with a recess corresponding to the cooling plate for receiving the cooling plate.

9. The arc furnace heat shield of claim 1, wherein said cover plate has a planar configuration on a side thereof remote from said heat shield.

10. An electric arc furnace comprising a furnace body, an electrode and the electric arc furnace heat shielding device of any one of claims 1 to 9, wherein the electric arc furnace heat shielding device is arranged on the furnace body, and the first through hole, the second through hole and the third through hole of the electric arc furnace heat shielding device are communicated to form a through hole for accommodating the movement of the electrode.

Images