JP7081029B1 - Electrode device for ultra-high temperature heating furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode device of an ultra-high temperature heating furnace capable of suppressing melting damage of a ceramic insulator supporting a graphite electrode portion in a circular tubular sleeve. SOLUTION: In a portion inside a sleeve 64 of an electrode device 18, a second circular tubular insulator 82 is shielded between a second circular tubular insulator 82 made of alumina porcelain, which is a ceramic insulator, and an opening of the sleeve 64. A ceramic shield 84 that is provided and has a higher melting point than the second circular tubular insulator 82 is provided. As a result, it is possible to suppress the melting damage of the second circular tubular insulator 82 that supports the graphite electrode portion 68 in the circular tubular sleeve 64. [Selection diagram] FIG. 5

Description

The present invention relates to the structure of an electrode device of an ultra-high temperature heating furnace that performs heat treatment using a heater.

In the graphitization treatment for producing carbon fibers, graphite sheets, gas diffusion layer base materials for fuel cells, etc., it is required to perform heat treatment in an ultra-high temperature region of 2000 ° C. or higher. In such an ultra-high temperature heating furnace in which heat treatment is performed in an ultra-high temperature region of about 2000 ° C., an electrode device for supplying power to a carbon heater provided in the furnace is provided in a state of penetrating the furnace wall. The electrode device used in such an ultra-high temperature heating furnace includes a graphite electrode portion connected to a carbon heater and a water-cooled metal electrode portion connected to the graphite electrode portion via a connection portion made of refractory metal. It is supported in a circular tubular sleeve provided so as to penetrate the furnace body, for example, via an annular or cylindrical ceramic insulator made of alumina. For example, the electrode device described in Patent Document 1 is that.

As a result, it is said that the connection portion of the water-cooled metal electrode portion is prevented from being significantly impaired in mechanical strength due to high temperature, and heat treatment can be performed in an ultra-high temperature region of 2000 ° C. or higher.

Jikkai Sho 58-90694

By the way, in the above-mentioned electrode device, among the graphite electrode portion, the connection portion made of refractory metal, and the water-cooled metal electrode portion, the ceramic insulator that supports at least the graphite electrode portion in the circular tubular sleeve is radiated from the inside of the furnace. Since the wire is directly received, there is an inconvenience of melting. Such inconvenience became more remarkable in the ultra-high temperature region of 2500 ° C to 3000 ° C.

The present invention has been made in the background of the above circumstances, and an object thereof is an ultra-high temperature capable of suppressing melting damage of a ceramic insulator supporting a graphite electrode portion in a circular tubular sleeve. The purpose is to provide an electrode device for a heating furnace.

As a result of repeated studies against the background of the above circumstances, the present inventors have put a sleeve opening provided through the furnace body between the sleeve opening and the ceramic insulator that supports the graphite electrode portion in the sleeve. It has been found that if a shield made of a material having a higher heat resistance than the ceramic insulator is provided so as to block the radiation incident from the opening of the sleeve, the melting damage of the ceramic insulator is suitably suppressed. The present invention has been made based on such findings.

That is, the gist of the first invention is the outside of the water-cooled type, which includes (a) a metal electrode portion and a graphite electrode portion connected to the metal electrode portion in a row, and constitutes a furnace wall of an ultra-high temperature heating furnace. The outer end portion of the graphite electrode portion is arranged radially through the ceramic insulator in the circular tube member and the sleeve fixed through the shell and the heat insulating panel, respectively, and the inner end portion of the graphite electrode portion is arranged. It is an electrode device of an ultra-high temperature heating furnace that performs a graphite treatment in an ultra-high temperature region, which is connected to a pair of longitudinal carbon heaters arranged inside the furnace wall in parallel with the furnace wall (b). (C) A ceramic shield provided in the sleeve so as to shield the ceramic insulator between the ceramic insulator and the opening of the sleeve and has a higher melting point than the ceramic insulator (c). ) The metal electrode portion is fixed to the furnace wall, (d) the metal electrode portion is formed with a blind hole to which a pipe for circulating cooling water is connected , and (e) the inner end of the graphite electrode portion. The portion is connected to the carbon heater inside the furnace wall via a longitudinal block parallel to the inner wall surface of the furnace wall, and (f) the longitudinal block is from the diameter of the graphite electrode portion. Also has a large width dimension, (g) the inner end of the graphite electrode is connected to the longitudinal center of the longitudinal block, and the pair of longitudinal blocks at both ends of the longitudinal block. The ends of the carbon heaters are connected to each other.

The gist of the second invention is that in the first invention, the ceramic insulator is an alumina porcelain, and the ceramic shield is made of any one of aluminum nitride, silicon carbide, zirconia, and boron nitride. It is manufactured.

The gist of the third invention is that, in the first invention or the second invention, the graphite electrode portion protrudes between the ceramic shield and the opening of the sleeve to prevent the ceramic shield from falling off. The protrusions are formed.

The gist of the fourth invention is that in any one of the first to third inventions, the ultra-high temperature heating furnace has a furnace chamber surrounded by six furnace walls, and the carbon heater. Is located inside the six-sided furnace wall.

According to the electrode device of the ultra-high temperature heating furnace of the first invention, the ceramic insulator is provided so as to shield the ceramic insulator between the ceramic insulator and the opening of the sleeve in the sleeve, and the ceramic insulator is used. Also provided with a ceramic shield having a high melting point, the metal electrode portion is fixed to the furnace wall, and a blind hole to which a pipe for circulating cooling water is connected is formed in the metal electrode portion, and the graphite is formed. The inner end of the electrode portion is connected to the carbon heater inside the furnace wall via a longitudinal block parallel to the inner wall surface of the furnace wall, and the longitudinal block is the graphite electrode portion of the graphite electrode portion. The width dimension is larger than the diameter, the inner end portion of the graphite electrode portion is connected to the central portion in the longitudinal direction of the longitudinal block, and the pair of carbons are connected to both ends in the longitudinal direction of the longitudinal block. Since the ends of the heaters are connected to each other, it is possible to suppress the melting damage of the ceramic insulator that supports the graphite electrode portion in the electrically insulated state in the circular tubular sleeve.

According to the electrode device of the ultra-high temperature heating furnace of the second invention, the ceramic insulator is an alumina porcelain, and the ceramic shield is made of any one of aluminum nitride, silicon carbide, zirconia, and boron nitride. It is manufactured. Since the ceramic insulator is composed of aluminum nitride, silicon carbide, zirconia, and boron nitride, which have a higher melting point than alumina porcelain, it is possible to suppress melting damage of the ceramic insulator that supports the graphite electrode portion in the circular tubular sleeve. Can be done.

According to the electrode device of the ultra-high temperature heating furnace of the third invention, the graphite electrode portion is formed with protrusions protruding between the ceramic shield and the opening of the sleeve to prevent the ceramic shield from falling off. Therefore, especially when the electrode device is provided on the ceiling or door of the outer shell, it is possible to prevent the ceramic shield and the ceramic insulator from falling out of the sleeve.

According to the electrode device of the ultra-high temperature heating furnace of the fourth invention, the ultra-high temperature heating furnace has a furnace chamber surrounded by a six-sided furnace wall, and the carbon heater is inside the six-sided furnace wall. Even if high-energy radiation from the ultra-high temperature furnace chamber enters the circular tubular sleeve, the ceramic insulator that supports the graphite electrode in an electrically insulated state is melted. Can be suppressed.

It is a front view which shows an example of the ultra-high temperature heating furnace of one Example of this invention by cutting out a part. It is a plan sectional view of the ultra-high temperature heating furnace of FIG. 1, and is the sectional view of II-II of FIG. It is a vertical sectional view of the ultra-high temperature heating furnace of FIG. 1, and is the sectional view III-III sectional view of FIG. It is sectional drawing explaining the electrode provided in the ultra-high temperature heating furnace of FIG. 1 in an enlarged manner. It is a figure which shows the main part of the electrode device of FIG. 4 in an enlarged manner.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a front view showing an ultra-high temperature heating furnace (hereinafter referred to as a heating furnace) 10 according to an embodiment of the present invention with a part cut out. FIG. 2 shows a plan sectional view of the heating furnace 10, and FIG. 3 shows a vertical sectional view of the heating furnace 10. The heating furnace 10 includes a box-shaped outer shell 12 fixed on the base 11, a square tubular heat insulating unit 14 and a flat heat insulating unit 16 provided inside the outer shell 12, and an outer shell 12 and a corner. By being supported by the tips of a plurality of electrode devices 18 penetrating the tubular heat insulating unit 14 or the flat heat insulating unit 16, the inside of the square tubular heat insulating unit 14 and the flat heat insulating unit 16 is outside the box type. A carbon heater 20 provided along the six surfaces of the shell 12 and an object to be treated (not shown) are detachably fixed to the outer shell 12 inside each of the carbon heaters 20 so as to be placed in a heated state on the six surfaces. It is equipped with a mounting table 21.

The box-shaped outer shell 12 has a square tube-shaped outer shell body 22 corresponding to four of the six surfaces excluding two horizontally facing each other, and an outer shell corresponding to the two horizontally facing surfaces. It includes a pair of front side outer shell plates 28 and back side outer shell plates 30 that airtightly close the front side opening 24 and the back side opening 26 of the shell body 22, respectively. The peripheral edge of the front outer shell plate 28 is fastened to the front opening 24 of the outer shell main body 22 so as to be detachable, that is, openable and closable by a plurality of actuator-attached fastening devices 32, and the peripheral edge of the back surface side outer shell plate 30 is attached. It is fastened to the back surface side opening 26 of the outer shell main body 22 so as to be detachable, that is, openable and closable by a plurality of fastening devices 34 with handles. In addition, only one of the pair of front side outer shell plates 28 and the back side outer shell plate 30 may be fastened to the outer shell main body 22 so as to be openable and closable, and the other may be fixed to the outer shell main body 22.

The outer shell main body 22, the pair of front side outer shell plates 28, and the back side outer shell plate 30 are separated from each other by a gap D through which a refrigerant passes between the outer plate 38 having a plurality of reinforcing rib plates 36 and the outer plate 38. An inner plate 40, which is liquid-tightly fixed to the outer plate 38, is provided. The outer shell main body 22, the front side outer shell plate 28, and the back side outer shell plate 30 are each made of a heat-resistant steel plate, for example, a stainless steel plate, and suppress the temperature rise of the outer shell 12, and the square tube type heat insulating unit 14 and the flat surface. It also functions as a liquid-cooled jacket for cooling the mold insulation unit 16. The front side outer shell plate 28 functions as a door that is opened and closed when the object to be processed is taken in and out, and the back side outer shell plate 30 is a plurality of carbon fiber felt 46s and a pair of outer holding plates 48. It also functions as a door that is opened and closed when the heat insulating member such as the inner holding plate 50 is replaced.

The square tube type heat insulating unit 14 is located in the outer shell main body 22 corresponding to four of the six surfaces of the outer shell 12 excluding the two facing surfaces thereof, and the outer shell main body 22 is attached and detached by a plurality of electrode devices 18. The inner frame material 42 made of heat-resistant steel, for example, stainless steel, which was provided as possible, was fixed to the inner frame material 42 so as to face the inner wall surface of the four surfaces of the outer shell 12, that is, the four surfaces of the outer shell main body 22. A plurality of heat insulating panels 44 are integrally provided and placed in the outer shell main body 22. In this embodiment, the outer shell 12 and the heat insulating panel 44 form the six-sided furnace wall of the heating furnace 10, the carbon heater 20 is provided inside the six-sided furnace wall, and the inside of the heating furnace 10 is provided with a carbon heater 20. A furnace chamber surrounded by the six furnace walls is formed. In the furnace chamber, the space surrounded by the carbon heater 20 is heated to an ultra-high temperature.

In the heat insulating panel 44, a plurality of carbon fiber felts 46 laminated to a predetermined thickness were sandwiched in the thickness direction of the carbon fiber felt 46 by a laminated body of a pair of outer holding plates 48 and inner holding plates 50. These are detachably fixed to the inner frame material 42 by the through heat resistant bolts 52. In this embodiment, the plurality of carbon fiber felts 46, and the pair of outer holding plates 48 and inner holding plates 50 function as heat insulating members.

FIG. 4 shows a cross section of the electrode device 18 fixed to the outer shell 12 and supporting the carbon heater 20. The electrode device 18 is provided so as to penetrate the outer shell main body 22 constituting the furnace wall, the front side outer shell plate 28 or the back side outer shell plate 30, and the heat insulating panel 44, respectively. Since it is configured, FIG. 9 shows an example provided on the outer shell main body 22 as a representative. In FIG. 9, the outer shell main body 22 is provided with a circular tube member 62 for passing the electrode device 18 through the outer shell main body 22 by welding, and the heat insulating panel 44 is provided. In a state in which a graphite circular tubular sleeve 64 is fixed so as to penetrate the heat insulating panel 44.

The electrode device 18 includes a short columnar metal electrode portion 66 and a columnar graphite electrode portion 68 concentrically connected and fixed to the metal electrode portion 66. The metal electrode portion 66 is formed with a blind hole 70 that opens on the outer end surface, and the blind hole 70 is connected to a pipe 72 that circulates cooling water in the blind hole 70. The metal electrode portion 66 is composed of a metal conductor such as copper, a copper alloy, and an aluminum alloy, which are thermal conductors, and is a water-cooled electrode portion that is constantly cooled by a refrigerant such as water when the heating furnace 10 is in operation.

A seat plate 74 having a predetermined thickness for fixing the electrode device 18 is fixed to the outside of the outer shell main body 22 by welding, and a mounting flange 76 integrally protruding from the metal electrode portion 66 to the outer peripheral side is an insulating sheet. The electrode device 18 is fixed to the outer shell main body 22 in a state of penetrating the circular tube member 62 by being fastened to the seat plate 74 by the fastening screw 79 via the 78. A first circular tubular porcelain 80 having a diameter smaller than that of the circular tube member 62 is interposed between the inner peripheral surface of the circular tube member 62 and the outer peripheral surface of the metal electrode portion 66 in the radial direction. The electrical insulation between the metal electrode portion 66 and the metal electrode portion 66 is maintained.

The columnar graphite electrode portion 68, which is concentrically fixed to the metal electrode portion 66 in a concentric state, preferably has a larger diameter than the metal electrode portion 66 and substantially the same diameter as the outer diameter of the first circular tubular porcelain 80. be. A second portion of the outer end of the graphite electrode portion 68 overlaps the end of the first circular tubular insulator 80 in a state of being radially interposed between the outer peripheral surface of the graphite electrode portion 68 and the inner peripheral surface of the sleeve 64. A circular tubular insulator 82 is fitted to maintain electrical insulation of the graphite electrode portion 68. The second circular tubular insulator 82 is fitted in a graphite circular tubular sleeve 64 except for its outer end portion, and serves as a ceramic insulator between the outer peripheral surface of the graphite electrode portion 68 and the inner peripheral surface of the sleeve 64. It is functioning. As a result, the outer end of the graphite electrode portion 68 is covered with the second cylindrical insulator 82. Further, a predetermined gap P is formed between the graphite circular tubular sleeve 64 and the columnar graphite electrode portion 68 inserted inside the sleeve 64. The first circular tubular insulator 80 and the second circular tubular insulator 82 are ceramic insulators, respectively, and are preferably made of alumina porcelain.

As shown in an enlarged manner in FIG. 5, in the graphite circular tubular sleeve 64, between the second circular tubular insulator 82 and the inner opening of the sleeve 64, the carbon heater 20 and the carbon heater 20 with respect to the second circular tubular insulator 82 An annular ceramic shield 84 that shields radiation from the inside of the furnace is arranged at a position adjacent to the second circular tubular insulator 82 in a state of being fitted to the outer peripheral surface of the graphite electrode portion 68. The ceramic shield 84 is composed of a substance having a melting point higher than the melting point of the second circular tubular porcelain 82, for example, a ceramic material of any one of aluminum nitride, silicon carbide, zirconia, and boron nitride. The radial width dimension of the ceramic shield 84 is less than or equal to the gap P between the graphite circular tubular sleeve 64 and the cylindrical graphite electrode portion 68 inserted inside the sleeve 64, and is about half of the gap P. Even with the dimensions of, a tentative effect can be obtained.

Further, in the graphite circular tubular sleeve 64, the ceramic shield 84 and the sleeve 64 are on the outer peripheral surface of the graphite electrode portion 68 between the ceramic shield 84 and the second circular tubular porcelain 82 and the inner opening of the sleeve 64. A protrusion 85 for preventing the ceramic shield 84 from moving or falling off is formed so as to protrude inward in the radial direction. The protrusion 85 may have a continuous shape in the circumferential direction, but may have a discontinuous shape in the circumferential direction or a shape protruding at one place. The shape of the protrusion 85 may be a height and a circumferential length that can be engaged with the ceramic shield 84.

Returning to FIG. 4, the inner end portion of the graphite electrode portion 68 is detachably connected to the block 90 to which the end portion of the carbon heater 20 is connected, so that the electrode device 18 supports the carbon heater 20. It is connected to the carbon heater 20. The carbon heater 20 is heated in an ultra-high temperature region of 2000 ° C. to 3000 ° C. by supplying low voltage and high current power from the electrode device 18.

In the heating furnace 10, the object to be treated on the mounting table 21 has an ultra-high temperature region of 2000 ° C. to 3000 ° C., preferably 2500 ° C. to 3000 ° C. in a non-oxidizing atmosphere, for example, an inert gas atmosphere such as nitrogen or argon. When the graphitization treatment is repeated in the ultra-high temperature region of the above, the heat insulating members such as the carbon fiber felt 46, the heat insulating board 54, and the graphite plate 56 are consumed. The mold insulation unit 16 is replaced. At this time, by removing the mounting table 21, the carbon heater 20, the electrode device 18, the temperature sensor (not shown), and the like, the square tubular heat insulating unit 14 and the flat heat insulating unit 16 whose heat insulating members have been consumed can be easily removed. The new square tube type heat insulating unit 14 and the flat type heat insulating unit 16 are positioned and the electrode device 18, the carbon heater 20, and the like are mounted to position and fix the new square tube type heat insulating unit 14.

In the heating furnace 10 configured as described above, the object to be treated on the mounting table 21 has an ultra-high temperature region of 2000 ° C. to 3000 ° C. under a non-oxidizing atmosphere, for example, under an inert gas atmosphere such as nitrogen or argon. For example, when the graphitization treatment is performed in an ultra-high temperature region of 2500 ° C. to 3000 ° C., high-energy radiation rays are generated from the carbon heater 20 or the like in the furnace and enter the inner opening of the sleeve 64. At this time, high energy radiation is received by the ceramic shield 84 having a higher melting point than the second circular tubular insulator 82 made of alumina porcelain, and it is avoided that the second circular tubular insulator 82 receives high energy radiation. Therefore, the melting damage of the second circular tubular insulator 82 is suppressed.

As described above, according to the electrode device 18 of the heating furnace 10 of the present embodiment, in the sleeve 64, between the second circular tubular insulator 82 made of alumina porcelain, which is a ceramic insulator, and the opening of the sleeve 64. A ceramic shield 84 which is provided so as to shield the second circular tubular insulator 82 and has a higher melting point than the second circular tubular insulator 82 is provided. As a result, it is possible to suppress the melting damage of the second circular tubular insulator 82 that supports the graphite electrode portion 68 in the circular tubular sleeve 64.

Further, according to the electrode device 18 of the heating furnace 10 of the present embodiment, the ceramic shield 84 is manufactured from any one of aluminum nitride, silicon carbide, zirconia, and boron nitride. Since these aluminum nitride, silicon carbide, zirconia, and boron nitride have a higher melting point than the second circular tubular insulator 82 made of alumina porcelain, the second circular tubular insulator that supports the graphite electrode portion 68 in the circular tubular sleeve 64. It is possible to suppress the melting damage of 82.

Further, according to the electrode device 18 of the heating furnace 10 of the present embodiment, in the sleeve 64, the graphite electrode portion 68 protrudes between the ceramic shield 84 and the opening of the sleeve 64, and the ceramic shield 84 falls off. Since the protrusion 85 for preventing the above-mentioned is formed, it is possible to prevent the ceramic shield 84 and the second circular tubular furnace 82 from falling out of the sleeve 64. In particular, when the electrode device 18 is provided on the ceiling of the outer shell 12 or the front side outer shell plate 28 functioning as a door, such an effect becomes remarkable.

Although the present invention has been described above with reference to the drawings, the present invention is also applicable to other aspects.

For example, in the above-described embodiment, the annular ceramic shield 84 that shields the second circular tubular insulator 82 from the carbon heater 20 and the radiation rays from the inside of the furnace has the same radial height as the second circular tubular insulator 82. It had a height, but it does not necessarily have to have a similar height. Even if the ceramic shield 84 has a shape lower than the radial height of the second circular tubular insulator 82 and the height of the second circular tubular insulator 82 shields the area at a predetermined ratio, it is tentative. The effect is obtained.

Further, in the above-described embodiment, one annular ceramic shield 84 is arranged between the second circular tubular insulator 82 and the opening of the sleeve 64 in the sleeve 64, but a plurality of ceramic shields are provided. The thing 84 may be arranged.

Further, in the above-described embodiment, the annular ceramic shield 84 is arranged at a position adjacent to the second circular tubular insulator 82, but is not necessarily adjacent to the second circular tubular insulator 82, but is not necessarily adjacent to the sleeve 64. The position may be separated from the 2-circular tubular insulator 82.

Further, in the above-described embodiment, the metal electrode portion 66 and the graphite electrode portion 68 connected to the metal electrode portion 66 are directly connected, but indirectly via a connecting member made of a refractory metal such as molybdenum. It may be connected to.

Further, in the above-described embodiment, the height of the protrusion 85 may be such that it can engage with the ceramic shield 84 in order to prevent the ceramic shield 84 from falling off, but the second circular tubular insulator may be used. It may be as high as 82. In this case, the protrusion 85 also has a function of shielding the radiation line.

Further, in the above-described embodiment, the protrusion 85 is projected from the outer peripheral surface of the graphite electrode portion 68 between the ceramic shield 84 and the opening of the sleeve 64, but the ceramic shield 84 is projected from the inner peripheral surface of the sleeve 64. It may be projected between the sleeve 64 and the opening of the sleeve 64.

Further, a protrusion 85 for preventing the ceramic shield 84 from falling off was provided on the outer peripheral surface of the graphite electrode portion 68 of the electrode device 18 of the above-mentioned embodiment, but the electrode device 18 is on the side surface of the heating furnace 12. When it is attached to the furnace wall, it does not necessarily have to be provided.

Further, the electrode device 18 of the above-described embodiment is provided on the furnace wall surrounding the furnace chamber of the single furnace type ultra-high temperature heating furnace 10, but for example, a continuous furnace type ultra-high temperature heating furnace or a shuttle furnace type super high temperature heating furnace. It may be provided on the furnace wall of the high temperature heating furnace.

In addition, although not illustrated one by one, the present invention is carried out with various modifications within a range not deviating from the gist thereof.

10: Ultra-high temperature heating furnace 18: Electrode device 20: Carbon heater 54: Furnace chamber 64: Sleeve 64a: Sleeve opening 66: Metal electrode part 68: Graphite electrode part 82: Second circular tubular insulator (ceramic insulator)
84: Ceramic shield 85: Protrusion

Claims (4)

A circular tube provided with a metal electrode portion and a graphite electrode portion connected to the metal electrode portion, penetrating a water-cooled outer shell and a heat insulating panel constituting the furnace wall of an ultra-high temperature heating furnace, respectively. The outer end of the graphite electrode portion is arranged in the member and the sleeve via the ceramic insulator in the radial direction, and the inner end portion of the graphite electrode portion is arranged inside the furnace wall in parallel with the inner wall surface of the furnace wall. It is an electrode device of an ultra-high temperature heating furnace that performs graphitization treatment in an ultra-high temperature region, which is connected to a pair of long carbon heaters arranged.
A ceramic shield provided in the sleeve so as to shield the ceramic insulator between the ceramic insulator and the opening of the sleeve and has a melting point higher than that of the ceramic insulator is provided.
The metal electrode portion is fixed to the furnace wall and is fixed to the furnace wall.
A blind hole is formed in the metal electrode portion to which a pipe for circulating cooling water is connected.
The inner end of the graphite electrode portion is connected to the end of the pair of carbon heaters inside the furnace wall via a longitudinal block parallel to the inner wall surface of the furnace wall.
The longitudinal block has a width dimension larger than the diameter of the graphite electrode portion.
The inner ends of the graphite electrodes are connected to the central portion of the longitudinal block in the longitudinal direction, and the ends of the pair of carbon heaters are connected to both ends of the longitudinal block in the longitudinal direction . An electrode device for an ultra-high temperature heating furnace. The electrode device for an ultra-high temperature heating furnace according to claim 1, wherein the ceramic shield is manufactured from any one of aluminum nitride, silicon carbide, zirconia, and boron nitride. The superimposition of claim 1 or 2, wherein the graphite electrode portion is formed with a protrusion protruding between the ceramic shield and the opening of the sleeve to prevent the ceramic shield from falling off. Electrode device for high temperature heating furnace. The ultra-high temperature heating path has a furnace chamber surrounded by six furnace walls.
The electrode device for an ultra-high temperature heating furnace according to any one of claims 1 to 3, wherein the carbon heaters are respectively arranged inside the six-sided furnace wall.

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