EP1881285A1 - Ceiling of an electric arc furnace and central part thereof - Google Patents

Ceiling of an electric arc furnace and central part thereof Download PDF

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Publication number
EP1881285A1
EP1881285A1 EP06117550A EP06117550A EP1881285A1 EP 1881285 A1 EP1881285 A1 EP 1881285A1 EP 06117550 A EP06117550 A EP 06117550A EP 06117550 A EP06117550 A EP 06117550A EP 1881285 A1 EP1881285 A1 EP 1881285A1
Authority
EP
European Patent Office
Prior art keywords
roof
peripheral
central
central portion
rack according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP06117550A
Other languages
German (de)
French (fr)
Inventor
Serge Fontaine
Paolo Esposito
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vesuvius Crucible Co
Original Assignee
Vesuvius Crucible Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Vesuvius Crucible Co filed Critical Vesuvius Crucible Co
Priority to EP06117550A priority Critical patent/EP1881285A1/en
Priority to US12/374,369 priority patent/US20090168831A1/en
Priority to BRPI0714443-1A priority patent/BRPI0714443A2/en
Priority to EP07786229A priority patent/EP2047197B1/en
Priority to MX2009000754A priority patent/MX2009000754A/en
Priority to AT07786229T priority patent/ATE515671T1/en
Priority to PCT/EP2007/006481 priority patent/WO2008009468A1/en
Priority to CA002656734A priority patent/CA2656734A1/en
Publication of EP1881285A1 publication Critical patent/EP1881285A1/en
Priority to CO09008199A priority patent/CO6160252A2/en
Priority to MA31640A priority patent/MA30647B1/en
Withdrawn legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00—Casings; Linings; Walls; Roofs
    • F27D1/02—Crowns; Roofs
    • F27D1/025—Roofs supported around their periphery, e.g. arched roofs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
    • F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
    • F27B3/12—Working chambers or casings; Supports therefor
    • F27B3/16—Walls; Roofs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00—Casings; Linings; Walls; Roofs
    • F27D1/18—Door frames; Doors, lids, removable covers
    • F27D1/1808—Removable covers
    • F27D1/1816—Removable covers specially adapted for arc furnaces

Definitions

  • the present invention relates to an electric arc furnace vault and a central portion for an electric arc furnace vault.
  • an electric arc furnace comprising a closed vessel, separating the interior from the outside of the furnace.
  • This tank has an upper vault with an access opening to the interior of the furnace generally closed by a roof.
  • the roofer has the general shape of a disk with a concave inner surface.
  • the roof made of refractory material resistant to high temperatures, is provided with orifices for the passage of electrodes for generating an electric arc inside the oven.
  • the roof is one of the parts of the furnace particularly exposed to the heat released by the electric arc, because this electric arc is produced mainly opposite the internal surface of the roof, while it is further away from the internal surface of other parts of the tank.
  • the inner surface of the roof is therefore sensitive to wear. As a result, it is necessary to regularly replace the oven during the life of the oven.
  • the roof is a particularly heavy and large part, so that its replacement is difficult and expensive, especially when the replacement vajtain must be transported from a place of manufacture to the place of the electric arc furnace.
  • the present invention seeks to overcome this difficulty by providing an arc furnace vault less sensitive to wear, so that it must be replaced less often.
  • the invention relates to a vault of electric arc furnace, characterized in that it comprises a central portion and a peripheral portion surrounding the central portion, each of these portions being provided with an internal surface intended for to be directed towards the inside of the oven, the inner surfaces of the peripheral and central portions forming between them a recess such that the internal surface of the central part is set back with respect to the inner surface of the peripheral part by considering the inside of the oven.
  • the roof according to the invention offers less grip at the highest temperature zone generated by the electric arc in the center of the oven, because of the distance from the part of the roof that is most sensitive to wear. As a result, the roof is worn less quickly than in the state of the art.
  • the inner surface of the peripheral portion of the roof can be positioned at the same height relative to the inside of the oven as in the state of the art, so that it is not necessary to modify the ovens existing.
  • the lifetime of the roof is longer than in the state of the art, without adding material.
  • a roof according to the invention may further comprise one or more of the following features.
  • the inner surface of the central portion is substantially flat. Indeed, as the inner surface of the central portion is recessed relative to the inner surface of the peripheral portion, it is not necessary that it is concave, while the internal surface of the vault of the state of the technique is usually concave. As it is known that it is easier to produce flat surfaces than concave surfaces, especially on parts having such dimensions, the roof according to the invention is easier to achieve.
  • the central and peripheral parts are reported one on the other. This results in several advantages. First of all, if the roof is worn, it is possible to replace only the central part, which is less bulky and lighter than the full roof. Furthermore, because the central portion and the peripheral portion are attached to one another, it is conceivable to manufacture a standard central portion, which is the same regardless of the oven on which the roof is intended to be mounted, the peripheral portion allowing the adaptation of the roof to the size of each oven. Thus, the central part, which is possibly the part of the vault most often replaced, is the same whatever the oven. It is therefore less expensive to achieve.
  • the central and peripheral parts comprise complementary interlocking surfaces of revolution provided with mutual positioning means of the central and peripheral parts.
  • these positioning means facilitate the assembly of the central portion on the peripheral portion, particularly when only replacing the central portion of the vault.
  • At least one of the interlocking surfaces of the central and peripheral portions comprises a mutual axial positioning shoulder and radial portions, cooperating with a complementary portion of the other interlocking surfaces. Thanks to this shoulder, provided either on the central portion or on the peripheral portion, the axial and radial positioning of the parts between them is particularly easy and does not require reported means. In addition, the sealing of the oven is facilitated.
  • the complementary interlocking surfaces have general frustoconical shapes.
  • the complementary interlocking surfaces provide mutual axial and radial positioning, despite manufacturing tolerances of the central and peripheral parts, while effectively ensuring the tightness of the oven.
  • the peripheral portion has a generally annular shape formed by the meeting of at least two segments, preferably three segments.
  • This embodiment is particularly interesting, because it is possible to have separate segments before mounting the roof oven on the oven, especially during its transport. Now, we know that the diameter of the peripheral part of the roof is especially big. It is therefore achieved through the invention a considerable space saving. Moreover, if only one of the segments is damaged, one can only replace the latter.
  • the roof comprises means for connecting the segments together.
  • the peripheral portion can take the form of a single block while having used separate segments for transport.
  • these connecting means it is possible to disassemble, once the vajtain attached to the oven, the central portion of the peripheral portion, the latter remaining mounted on the oven, without the segments do not separate .
  • the connecting means comprise a belt surrounding the segments. This belt can ensure not only the connection of the segments together, but also the junction of the roof with the vault of the oven.
  • the belt carries anchoring means for a roof lifting tool. Indeed, it may be easier to provide these anchoring means on the belt rather than the peripheral or central portion of the roof.
  • the invention also relates to a central portion for an electric arc furnace roof, characterized in that it is intended to form a central portion of a roof as defined above.
  • FIGS. 1 to 3 show a vault 10 of an electric arc furnace according to a first embodiment of the invention.
  • the electric arc furnace comprises a generally closed vessel, generally in the form of a revolution about an axis X.
  • the tank comprises an upper vault 12, only part of which has been shown in FIG. 1.
  • the vault 12, separating the Inside I of the outside E of the oven, is provided with an access opening inside the oven, closed by the roofer 10.
  • the roof 10 comprises a central portion 14 and a peripheral portion 16 surrounding the central portion, mounted on each other, each being made of refractory material resistant to high temperatures.
  • the central portion 14 has a general flat disk shape, whose axis is substantially coincident with the axis X of the furnace, so that the central portion 14 is arranged opposite the furnace center where are generated the electric arcs.
  • This portion 14 is provided with three orifices 17 for the passage of electrodes, one of which is partially shown in dotted lines in FIG. electrodes being intended to generate electrical arcs in the interior I of the furnace.
  • the peripheral portion 16 has a generally annular shape, consisting of the joining of three segments 18, 20, 22, by means of connecting the segments between them.
  • the connecting means comprise, for example, refractory mortar comprising 90% alumina.
  • Part 16 is provided with a surface 23 joining the roof with the roof 12, cooperating with a complementary surface 23 of the roof 12.
  • the central portion 14 and the peripheral portion 16 are each provided with an inner surface 24, 26 intended to be directed towards the inside I of the oven, and an outer surface 28, 30 intended to be directed towards the outside E of the oven, each of the surfaces 24, 26, 28, 30 being substantially flat.
  • the internal surfaces of the peripheral portions 16 and central portion 14 form between them a recess d such that the inner surface 24 of the central portion is set back relative to the inner surface 26 of the peripheral portion. considering the interior I of the oven.
  • the central portion 14 and the peripheral portion 16 further comprise respective surfaces 32, 34 complementary interlocking revolution. These surfaces are provided with means 36, 38 of axial and radial mutual positioning of the central portion 14 and peripheral 16. These means comprise a shoulder 36 arranged on the interlocking surface 32 of the portion 14, cooperating with a complementary portion 38 of the interlocking surface 34 of the peripheral portion 16.
  • the different elements of the vault are first brought to the vicinity of the oven. Preferably, these elements are not yet assembled, so that the central portion 14 and each of the segments 18, 20, 22 can be transported separately.
  • the roofer 10 is then assembled by linking together the segments 18, 20, 22, thanks to the connecting means. Then the peripheral portion 16 thus assembled is mounted in the opening of the upper arch 12, by cooperating the complementary junction surfaces 23.
  • peripheral portion 16 Once the peripheral portion 16 assembled and mounted on the oven, it fits over the central portion 14, so as to complete the mounting of the roof on the oven.
  • the two parts 14, 16 may possibly be joined together by connecting means.
  • FIG 4 illustrates a second embodiment of the roof 10.
  • the elements similar to those of Figures 1 to 3 are designated by the same references.
  • interlocking surfaces 32, 34 complementary to the central portion 14 and peripheral 16 have general frustoconical shapes. These surfaces constitute axial and radial mutual positioning means for parts 14, 16.
  • the connecting means comprise a belt 40 surrounding the segments 18, 20, 22.
  • the belt 40 carries means 42 for anchoring a roof lifting tool 10.
  • the method of mounting the roof 10 of Figure 4 is similar to that of the roof of Figures 1 to 3. However, to join the segments 18, 20, 22 between them, the belt 40 is used. Additional bonds, such as refractory mortar, which allows to dismantle the central portion 14 of the furnace without detaching the segments of the peripheral portion 16.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)
  • Furnace Details (AREA)

Abstract

Refractory delta for an electric arc furnace comprises a central part (14) surrounded by a peripheral part (16), where the base of the central part is further removed from the interior of the furnace than that of the peripheral part.

Description

La présente invention concerne un voûtain de four à arc électrique et une partie centrale pour voûtain de four à arc électrique.The present invention relates to an electric arc furnace vault and a central portion for an electric arc furnace vault.

On connaît déjà dans l'état de la technique, notamment dans DE 41 00 960 , un four à arc électrique, comprenant une cuve fermée, séparant l'intérieur de l'extérieur du four. Cette cuve comporte une voûte supérieure munie d'une ouverture d'accès à l'intérieur du four généralement obturée par un voûtain. Le voûtain a la forme générale d'un disque muni d'une surface interne concave. Le voûtain, réalisé dans un matériau réfractaire résistant à de hautes températures, est pourvu d'orifices permettant le passage d'électrodes destinées à générer un arc électrique à l'intérieur du four.We already know in the state of the art, especially in DE 41 00 960 , an electric arc furnace, comprising a closed vessel, separating the interior from the outside of the furnace. This tank has an upper vault with an access opening to the interior of the furnace generally closed by a roof. The roofer has the general shape of a disk with a concave inner surface. The roof, made of refractory material resistant to high temperatures, is provided with orifices for the passage of electrodes for generating an electric arc inside the oven.

On sait que le voûtain est l'une des parties du four particulièrement exposée à la chaleur dégagée par l'arc électrique, car cet arc électrique est produit principalement en regard de la surface interne du voûtain, alors qu'il est davantage éloigné de la surface interne des autres parties de la cuve. La surface interne du voûtain est donc sensible à l'usure. Il en résulte que l'on doit régulièrement remplacer le voûtain au cours de la vie du four.We know that the roof is one of the parts of the furnace particularly exposed to the heat released by the electric arc, because this electric arc is produced mainly opposite the internal surface of the roof, while it is further away from the internal surface of other parts of the tank. The inner surface of the roof is therefore sensitive to wear. As a result, it is necessary to regularly replace the oven during the life of the oven.

Or, le voûtain est une pièce particulièrement lourde et de grande dimension, si bien que son remplacement est difficile et coûteux, notamment lorsque le voûtain de remplacement doit être transporté d'un lieu de fabrication jusqu'au lieu du four à arc électrique.However, the roof is a particularly heavy and large part, so that its replacement is difficult and expensive, especially when the replacement vajtain must be transported from a place of manufacture to the place of the electric arc furnace.

La présente invention vise à remédier à cette difficulté en fournissant un voûtain de four à arc électrique moins sensible à l'usure, de façon à devoir être remplacé moins souvent.The present invention seeks to overcome this difficulty by providing an arc furnace vault less sensitive to wear, so that it must be replaced less often.

A cet effet, l'invention à pour objet un voûtain de four à arc électrique, caractérisé en ce qu'il comprend une partie centrale et une partie périphérique entourant la partie centrale, chacune de ces parties étant munie d'une surface interne destinée à être dirigée vers l'intérieur du four, les surfaces internes des parties périphérique et centrale formant entre elles un décrochement tel que la surface interne de la partie centrale soit en retrait par rapport à la surface interne de la partie périphérique en considérant l'intérieur du four.For this purpose, the invention relates to a vault of electric arc furnace, characterized in that it comprises a central portion and a peripheral portion surrounding the central portion, each of these portions being provided with an internal surface intended for to be directed towards the inside of the oven, the inner surfaces of the peripheral and central portions forming between them a recess such that the internal surface of the central part is set back with respect to the inner surface of the peripheral part by considering the inside of the oven.

Ainsi, grâce au décrochement que forment entre elles les surfaces internes des parties périphérique et centrale, le voûtain selon l'invention offre moins de prise à la zone de température la plus élevée générée par l'arc électrique au centre du four, du fait de l'éloignement de la partie du voûtain la plus sensible à l'usure. Il en résulte que le voûtain s'use moins vite que dans l'état de la technique.Thus, thanks to the recess that form between them the inner surfaces of the peripheral and central parts, the roof according to the invention offers less grip at the highest temperature zone generated by the electric arc in the center of the oven, because of the distance from the part of the roof that is most sensitive to wear. As a result, the roof is worn less quickly than in the state of the art.

En outre, la surface interne de la partie périphérique du voûtain peut être positionnée à la même hauteur par rapport à l'intérieur du four que dans l'état de la technique, si bien qu'il n'est pas nécessaire de modifier les fours existants.In addition, the inner surface of the peripheral portion of the roof can be positioned at the same height relative to the inside of the oven as in the state of the art, so that it is not necessary to modify the ovens existing.

Grâce à l'invention, la durée de vie du voûtain est plus longue que dans l'état de la technique, sans pour autant y rajouter de la matière.Thanks to the invention, the lifetime of the roof is longer than in the state of the art, without adding material.

Un voûtain selon l'invention peut en outre comporter l'une ou plusieurs des caractéristiques suivantes.A roof according to the invention may further comprise one or more of the following features.

- La surface interne de la partie centrale est sensiblement plane. En effet, comme la surface interne de la partie centrale est en retrait par rapport à la surface interne de la partie périphérique, il n'est pas nécessaire qu'elle soit concave, alors que la surface interne du voûtain de l'état de la technique est généralement concave. Comme on sait qu'il est plus simple de réaliser des surfaces planes que des surfaces concaves, surtout sur des pièces ayant de telles dimensions, le voûtain selon l'invention est plus facile à réaliser.- The inner surface of the central portion is substantially flat. Indeed, as the inner surface of the central portion is recessed relative to the inner surface of the peripheral portion, it is not necessary that it is concave, while the internal surface of the vault of the state of the technique is usually concave. As it is known that it is easier to produce flat surfaces than concave surfaces, especially on parts having such dimensions, the roof according to the invention is easier to achieve.

- Les parties centrale et périphérique sont rapportées l'une sur l'autre. Il en résulte plusieurs avantages. Tout d'abord, si le voûtain est usé, il est possible de ne remplacer que la partie centrale, qui est moins volumineuse et moins lourde que le voûtain complet. Par ailleurs, du fait que la partie centrale et la partie périphérique sont rapportées l'une sur l'autre, il est envisageable de fabriquer une partie centrale standard, qui soit la même quel que soit le four sur lequel le voûtain est destiné à être monté, la partie périphérique permettant l'adaptation du voûtain à la taille de chaque four. Ainsi, la partie centrale, qui est éventuellement la partie du voûtain la plus souvent remplacée, est la même quel que soit le four. Elle est donc moins coûteuse à réaliser.- The central and peripheral parts are reported one on the other. This results in several advantages. First of all, if the roof is worn, it is possible to replace only the central part, which is less bulky and lighter than the full roof. Furthermore, because the central portion and the peripheral portion are attached to one another, it is conceivable to manufacture a standard central portion, which is the same regardless of the oven on which the roof is intended to be mounted, the peripheral portion allowing the adaptation of the roof to the size of each oven. Thus, the central part, which is possibly the part of the vault most often replaced, is the same whatever the oven. It is therefore less expensive to achieve.

- Les parties centrale et périphérique comprennent des surfaces d'emboîtement complémentaires de révolution munies de moyens de positionnement mutuel des parties centrale et périphérique. Ainsi, ces moyens de positionnement facilitent l'assemblage de la partie centrale sur la partie périphérique, en particulier lorsque l'on remplace uniquement la partie centrale du voûtain.- The central and peripheral parts comprise complementary interlocking surfaces of revolution provided with mutual positioning means of the central and peripheral parts. Thus, these positioning means facilitate the assembly of the central portion on the peripheral portion, particularly when only replacing the central portion of the vault.

- Au moins une des surfaces d'emboîtement des parties centrale et périphérique comprend un épaulement de positionnement mutuel axial et radial des parties, coopérant avec une partie complémentaire de l'autre des surfaces d'emboîtement. Grâce à cet épaulement, ménagé soit sur la partie centrale soit sur la partie périphérique, le positionnement axial et radial des parties entre elles est particulièrement facile et ne nécessite pas de moyens rapportés. En outre, l'étanchéité du four est facilitée.- At least one of the interlocking surfaces of the central and peripheral portions comprises a mutual axial positioning shoulder and radial portions, cooperating with a complementary portion of the other interlocking surfaces. Thanks to this shoulder, provided either on the central portion or on the peripheral portion, the axial and radial positioning of the parts between them is particularly easy and does not require reported means. In addition, the sealing of the oven is facilitated.

- Les surfaces d'emboîtement complémentaires ont des formes générales tronconiques. Ainsi, les surfaces d'emboîtement complémentaires assurent un positionnement mutuel axial et radial, et ce malgré des tolérances de fabrication des parties centrale et périphérique, tout en garantissant de façon efficace l'étanchéité du four.- The complementary interlocking surfaces have general frustoconical shapes. Thus, the complementary interlocking surfaces provide mutual axial and radial positioning, despite manufacturing tolerances of the central and peripheral parts, while effectively ensuring the tightness of the oven.

- La partie périphérique a une forme générale annulaire constituée par la réunion d'au moins deux segments, de préférence trois segments. Ce mode de réalisation est particulièrement intéressant, du fait qu'il est possible de disposer de segments séparés avant le montage du voûtain sur le four, notamment au cours de son transport. Or, on sait que le diamètre de la partie périphérique du voûtain est particulièrement grand. On réalise donc grâce à l'invention un gain de place considérable. Par ailleurs, si un seul des segments est abîmé, on peut ne remplacer que ce dernier.- The peripheral portion has a generally annular shape formed by the meeting of at least two segments, preferably three segments. This embodiment is particularly interesting, because it is possible to have separate segments before mounting the roof oven on the oven, especially during its transport. Now, we know that the diameter of the peripheral part of the roof is especially big. It is therefore achieved through the invention a considerable space saving. Moreover, if only one of the segments is damaged, one can only replace the latter.

- Le voûtain comprend des moyens de liaison des segments entre eux. Ainsi, la partie périphérique peut prendre la forme d'un seul bloc tout en ayant utilisé des segments séparés pour le transport. En outre, grâce à ces moyens de liaison, on peut envisager de démonter, une fois le voûtain rapporté sur le four, la partie centrale de la partie périphérique, cette dernière demeurant montée sur le four, sans pour autant que les segments ne se séparent.The roof comprises means for connecting the segments together. Thus, the peripheral portion can take the form of a single block while having used separate segments for transport. In addition, thanks to these connecting means, it is possible to disassemble, once the vajtain attached to the oven, the central portion of the peripheral portion, the latter remaining mounted on the oven, without the segments do not separate .

- Les moyens de liaison comprennent une ceinture entourant les segments. Cette ceinture peut assurer non seulement la liaison des segments entre eux, mais également la jonction du voûtain avec la voûte du four.- The connecting means comprise a belt surrounding the segments. This belt can ensure not only the connection of the segments together, but also the junction of the roof with the vault of the oven.

- La ceinture porte des moyens d'ancrage pour un outil de levage du voûtain. En effet, il peut être plus facile de prévoir ces moyens d'ancrage sur la ceinture plutôt que sur la partie périphérique ou centrale du voûtain.- The belt carries anchoring means for a roof lifting tool. Indeed, it may be easier to provide these anchoring means on the belt rather than the peripheral or central portion of the roof.

L'invention a également pour objet une partie centrale pour voûtain de four à arc électrique, caractérisé en ce qu'elle est destinée à former une partie centrale d'un voûtain tel que défini ci-dessus.The invention also relates to a central portion for an electric arc furnace roof, characterized in that it is intended to form a central portion of a roof as defined above.

L'invention sera mieux comprise à la lecture de la description qui va suivre, donnée uniquement à titre d'exemple et faite en se référant aux dessins, dans lesquels :

  • La figure 1 est une vue en coupe d'un voûtain selon un premier mode de réalisation de l'invention, selon le plan I-I de la figure 2 ;
  • La figure 2 est une vue de dessus du voûtain de la figure 1;
  • La figure 3 est une vue de dessus en perspective éclatée du voûtain de la figure 1 ; et
  • La figure 4 est une vue en coupe d'un voûtain selon un second mode de réalisation de l'invention.
The invention will be better understood on reading the description which follows, given solely by way of example and with reference to the drawings, in which:
  • Figure 1 is a sectional view of a roof according to a first embodiment of the invention, according to the plane II of Figure 2;
  • Figure 2 is a top view of the roof of Figure 1;
  • Figure 3 is an exploded perspective top view of the roof of Figure 1; and
  • Figure 4 is a sectional view of a roof according to a second embodiment of the invention.

On a représenté sur les figures 1 à 3 un voûtain 10 de four à arc électrique selon un premier mode de réalisation de l'invention.FIGS. 1 to 3 show a vault 10 of an electric arc furnace according to a first embodiment of the invention.

Le four à arc électrique comprend une cuve globalement fermée, de forme générale de révolution autour d'un axe X. La cuve comprend une voûte supérieure 12, dont seule une partie a été représentée sur la figure 1. La voûte 12, séparant l'intérieur I de l'extérieur E du four, est munie d'une ouverture d'accès à l'intérieur du four, obturée par le voûtain 10.The electric arc furnace comprises a generally closed vessel, generally in the form of a revolution about an axis X. The tank comprises an upper vault 12, only part of which has been shown in FIG. 1. The vault 12, separating the Inside I of the outside E of the oven, is provided with an access opening inside the oven, closed by the roofer 10.

Le voûtain 10 comprend une partie centrale 14 et une partie périphérique 16 entourant la partie centrale, rapportées l'une sur l'autre, chacune étant réalisée dans un matériau réfractaire résistant à de hautes températures.The roof 10 comprises a central portion 14 and a peripheral portion 16 surrounding the central portion, mounted on each other, each being made of refractory material resistant to high temperatures.

La partie centrale 14 a une forme générale de disque plat, dont l'axe est sensiblement confondu avec l'axe X du four, si bien que la partie centrale 14 est agencée en regard du centre du four où sont générés les arcs électriques. Cette partie 14 est pourvue de trois orifices 17 de passage d'électrodes, dont l'une est partiellement représentée en pointillés sur la figure 1, ces électrodes étant destinées à générer des arcs électriques à l'intérieur I du four.The central portion 14 has a general flat disk shape, whose axis is substantially coincident with the axis X of the furnace, so that the central portion 14 is arranged opposite the furnace center where are generated the electric arcs. This portion 14 is provided with three orifices 17 for the passage of electrodes, one of which is partially shown in dotted lines in FIG. electrodes being intended to generate electrical arcs in the interior I of the furnace.

La partie périphérique 16 a une forme générale annulaire, constituée par la réunion de trois segments 18, 20, 22, grâce à des moyens de liaison des segments entre eux. Les moyens de liaison comprennent par exemple du mortier réfractaire, comportant 90% d'alumine. La partie 16 est munie d'une surface 23 de jonction du voûtain avec la voûte 12, coopérant avec une surface complémentaire 23 de la voûte 12.The peripheral portion 16 has a generally annular shape, consisting of the joining of three segments 18, 20, 22, by means of connecting the segments between them. The connecting means comprise, for example, refractory mortar comprising 90% alumina. Part 16 is provided with a surface 23 joining the roof with the roof 12, cooperating with a complementary surface 23 of the roof 12.

La partie centrale 14 et la partie périphérique 16 sont munies chacune d'une surface interne 24, 26 destinée à être dirigée vers l'intérieur I du four, et d'une surface externe 28, 30 destinée à être dirigée vers l'extérieur E du four, chacune des surfaces 24, 26, 28, 30 étant sensiblement plane.The central portion 14 and the peripheral portion 16 are each provided with an inner surface 24, 26 intended to be directed towards the inside I of the oven, and an outer surface 28, 30 intended to be directed towards the outside E of the oven, each of the surfaces 24, 26, 28, 30 being substantially flat.

Comme on peut le voir sur la figure 1, les surfaces internes des parties périphérique 16 et centrale 14 forment entre elles un décrochement d tel que la surface interne 24 de la partie centrale soit en retrait par rapport à la surface interne 26 de la partie périphérique en considérant l'intérieur I du four.As can be seen in FIG. 1, the internal surfaces of the peripheral portions 16 and central portion 14 form between them a recess d such that the inner surface 24 of the central portion is set back relative to the inner surface 26 of the peripheral portion. considering the interior I of the oven.

La partie centrale 14 et la partie périphérique 16 comprennent en outre des surfaces respectives 32, 34 d'emboîtement complémentaires de révolution. Ces surfaces sont munies de moyens 36, 38 de positionnement mutuel axial et radial des parties centrale 14 et périphérique 16. Ces moyens comprennent un épaulement 36 agencée sur la surface d'emboîtement 32 de la partie 14, coopérant avec une partie complémentaire 38 de la surface d'emboîtement 34 de la partie périphérique 16.The central portion 14 and the peripheral portion 16 further comprise respective surfaces 32, 34 complementary interlocking revolution. These surfaces are provided with means 36, 38 of axial and radial mutual positioning of the central portion 14 and peripheral 16. These means comprise a shoulder 36 arranged on the interlocking surface 32 of the portion 14, cooperating with a complementary portion 38 of the interlocking surface 34 of the peripheral portion 16.

Les principaux aspects d'un procédé d'assemblage du voûtain selon l'invention et de son montage sur le four à arc électrique vont à présent être décrits.The main aspects of a method of assembling the roof of the invention and its mounting on the electric arc furnace will now be described.

Les différents éléments du voûtain sont tout d'abord amenés au voisinage du four. De préférence, ces éléments ne sont pas encore assemblés, si bien que l'on peut transporter la partie centrale 14 et chacun des segments 18, 20, 22 séparément.The different elements of the vault are first brought to the vicinity of the oven. Preferably, these elements are not yet assembled, so that the central portion 14 and each of the segments 18, 20, 22 can be transported separately.

On assemble ensuite le voûtain 10 en liant entre eux les segments 18, 20, 22, grâce aux moyens de liaison. Puis on monte la partie périphérique 16 ainsi assemblée dans l'ouverture de la voûte supérieure 12, en faisant coopérer les surfaces de jonction 23 complémentaires.The roofer 10 is then assembled by linking together the segments 18, 20, 22, thanks to the connecting means. Then the peripheral portion 16 thus assembled is mounted in the opening of the upper arch 12, by cooperating the complementary junction surfaces 23.

Une fois la partie périphérique 16 assemblée et montée sur le four, on emboîte pardessus la partie centrale 14, de façon à achever le montage du voûtain sur le four. On peut éventuellement solidariser les deux parties 14, 16 par des moyens de liaison.Once the peripheral portion 16 assembled and mounted on the oven, it fits over the central portion 14, so as to complete the mounting of the roof on the oven. The two parts 14, 16 may possibly be joined together by connecting means.

Si l'on souhaite par la suite remplacer la partie centrale 14 du voûtain, notamment pour des raisons d'usure, il suffit de remplacer la partie centrale 14, sans pour autant démonter la partie périphérique 16 du four.If it is desired later to replace the central portion 14 of the roof, especially for reasons of wear, just replace the central portion 14, without disassembling the peripheral portion 16 of the oven.

La figure 4 illustre un second mode de réalisation du voûtain 10. Les éléments analogues à ceux des figures 1 à 3 sont désignés par les références identiques.Figure 4 illustrates a second embodiment of the roof 10. The elements similar to those of Figures 1 to 3 are designated by the same references.

A la différence du premier mode de réalisation, les surfaces d'emboîtement 32, 34 complémentaires des parties centrale 14 et périphérique 16 ont des formes générales tronconiques. Ces surfaces constituent des moyens de positionnement mutuel axial et radial des parties 14, 16.Unlike the first embodiment, the interlocking surfaces 32, 34 complementary to the central portion 14 and peripheral 16 have general frustoconical shapes. These surfaces constitute axial and radial mutual positioning means for parts 14, 16.

En outre, les moyens de liaison comprennent une ceinture 40 entourant les segments 18, 20, 22. La ceinture 40 porte des moyens 42 d'ancrage pour un outil de levage du voûtain 10.In addition, the connecting means comprise a belt 40 surrounding the segments 18, 20, 22. The belt 40 carries means 42 for anchoring a roof lifting tool 10.

Le procédé de montage du voûtain 10 de la figure 4 est similaire à celui du voûtain des figures 1 à 3. Toutefois, pour réunir les segments 18, 20, 22 entre eux, on utilise la ceinture 40. On peut également utiliser des moyens de liaison supplémentaires, tels que du mortier réfractaire, ce qui permet de pouvoir démonter la partie centrale 14 du four sans pour autant désolidariser les segments de la partie périphérique 16.The method of mounting the roof 10 of Figure 4 is similar to that of the roof of Figures 1 to 3. However, to join the segments 18, 20, 22 between them, the belt 40 is used. additional bonds, such as refractory mortar, which allows to dismantle the central portion 14 of the furnace without detaching the segments of the peripheral portion 16.

Parmi les avantages de l'invention, on notera que l'on dispose d'un voûtain 10 dont la forme épouse sensiblement le profil d'usure généré par l'arc électrique au centre du four, si bien que la partie centrale 14 du voûtain, donc le voûtain 10 dans son ensemble, s'use moins rapidement qu'un voûtain de l'état de la technique. On dispose en outre, avec la partie centrale 14, d'une partie pouvant être standard, quelles que soient les dimensions du four sur lequel le voûtain est destiné à être monté. Enfin, on comprendra que les segments 18, 20, 22, en étant séparés, permettent un transport beaucoup plus aisé de la partie périphérique 16.Among the advantages of the invention, it will be noted that there is a roof 10 whose shape substantially matches the wear profile generated by the electric arc in the center of the oven, so that the central portion 14 of the ceiling The roofer 10 as a whole is used less quickly than a roof of the state of the art. In addition, with the central part 14, there is a part that can be standard, regardless of the dimensions of the oven on which the roof is intended to be mounted. Finally, it will be understood that the segments 18, 20, 22, being separated, allow a much easier transport of the peripheral portion 16.

Claims (11)

Voûtain (10) de four à arc électrique, caractérisé en ce qu'il comprend une partie centrale (14) et une partie périphérique (16) entourant la partie centrale (14), chacune de ces parties étant munie d'une surface interne (24, 26) destinée à être dirigée vers l'intérieur (I) du four, les surfaces internes des parties périphérique et centrale formant entre elles un décrochement (d) tel que la surface interne (24) de la partie centrale (14) soit en retrait par rapport à la surface interne (26) de la partie périphérique (16) en considérant l'intérieur du four.Electric arc furnace tank (10), characterized in that it comprises a central portion (14) and a peripheral portion (16) surrounding the central portion (14), each of these portions being provided with an inner surface ( 24, 26) intended to be directed towards the inside (I) of the oven, the inner surfaces of the peripheral and central portions forming between them a recess (d) such that the inner surface (24) of the central portion (14) is recessed relative to the inner surface (26) of the peripheral portion (16) considering the interior of the oven. Voûtain selon la revendication 1, dans lequel la surface interne (24) de la partie centrale est sensiblement plane.A roof according to claim 1, wherein the inner surface (24) of the central portion is substantially planar. Voûtain selon la revendication 1 ou 2, dans lequel les parties centrale (14) et périphérique (16) sont rapportées l'une sur l'autre.Roof rack according to claim 1 or 2, wherein the central (14) and peripheral (16) portions are attached to one another. Voûtain selon la revendication 3, dans lequel les parties centrale (14) et périphérique (16) comprennent des surfaces (32, 34) d'emboîtement complémentaires de révolution, munies de moyens de positionnement mutuel des parties centrale et périphérique.Roof rack according to claim 3, wherein the central portion (14) and peripheral (16) comprise surfaces (32, 34) complementary interlocking revolution, provided with mutual positioning means of the central and peripheral parts. Voûtain selon la revendication 4, dans lequel au moins une des surfaces d'emboîtement (32) des parties centrale (14) et périphérique (16) comprend un épaulement (36) de positionnement mutuel axial et radial des parties, coopérant avec une partie complémentaire (38) de l'autre (34) des surfaces d'emboîtement.Roof rack according to claim 4, wherein at least one of the interlocking surfaces (32) of the central (14) and peripheral (16) comprises a shoulder (36) for mutually axial and radial positioning of the parts cooperating with a complementary part. (38) of the other (34) interlocking surfaces. Voûtain selon la revendication 4, dans lequel les surfaces (32, 34) d'emboîtement complémentaires ont des formes générales tronconiques.Roof rack according to claim 4, wherein the complementary interlocking surfaces (32, 34) have generally frustoconical shapes. Voûtain selon l'une quelconque des revendications 3 à 6, dans lequel la partie périphérique (16) a une forme générale annulaire constituée par la réunion d'au moins deux segments, de préférence trois segments (18, 20, 22).Roof rack according to any one of claims 3 to 6, wherein the peripheral portion (16) has a generally annular shape formed by the union of at least two segments, preferably three segments (18, 20, 22). Voûtain selon la revendication 7, comprenant des moyens de liaison des segments entre eux.Roof rack according to claim 7, comprising means for connecting the segments together. Voûtain selon la revendication 8, dans lequel les moyens de liaison comprennent une ceinture (40) entourant les segments (18, 20, 22).Roof rack according to claim 8, wherein the connecting means comprise a belt (40) surrounding the segments (18, 20, 22). Voûtain selon la revendication 9, dans lequel la ceinture porte des moyens d'ancrage (42) pour un outil de levage du voûtain.Roof rack according to claim 9, wherein the belt carries anchoring means (42) for a roof lifting tool. Partie centrale (14) pour voûtain (10) de four à arc électrique, caractérisé en ce qu'elle est destinée à former une partie centrale d'un voûtain selon l'une quelconque des revendications 3 à 10.Central portion (14) for an electric arc furnace roof (10), characterized in that it is intended to form a central part of a ceiling element according to any one of claims 3 to 10.
EP06117550A 2006-07-20 2006-07-20 Ceiling of an electric arc furnace and central part thereof Withdrawn EP1881285A1 (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
EP06117550A EP1881285A1 (en) 2006-07-20 2006-07-20 Ceiling of an electric arc furnace and central part thereof
AT07786229T ATE515671T1 (en) 2006-07-20 2007-07-20 ARC FURNACE CEILING AND CENTER PART FOR THIS CEILING
BRPI0714443-1A BRPI0714443A2 (en) 2006-07-20 2007-07-20 electric arc furnace sky top, and central part for an electric arc furnace sky top
EP07786229A EP2047197B1 (en) 2006-07-20 2007-07-20 Electric arc furnace roof top and central portion for this roof top
MX2009000754A MX2009000754A (en) 2006-07-20 2007-07-20 Electric arc furnace roof top and central portion for this roof top.
US12/374,369 US20090168831A1 (en) 2006-07-20 2007-07-20 Electric arc furnace roof top and central portion for this roof top
PCT/EP2007/006481 WO2008009468A1 (en) 2006-07-20 2007-07-20 Electric arc furnace roof top and central portion for this roof top
CA002656734A CA2656734A1 (en) 2006-07-20 2007-07-20 Electric arc furnace roof top and central portion for this roof top
CO09008199A CO6160252A2 (en) 2006-07-20 2009-01-29 CEILING OF ELECTRIC ARC OVEN AND CENTRAL PORTION FOR THAT ROOFING
MA31640A MA30647B1 (en) 2006-07-20 2009-02-13 VOUTAIN OF OVEN WITH ELECTRIC ARC AND CENTRAL PART FOR THIS VOUTAIN

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP06117550A EP1881285A1 (en) 2006-07-20 2006-07-20 Ceiling of an electric arc furnace and central part thereof

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EP1881285A1 true EP1881285A1 (en) 2008-01-23

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EP06117550A Withdrawn EP1881285A1 (en) 2006-07-20 2006-07-20 Ceiling of an electric arc furnace and central part thereof
EP07786229A Active EP2047197B1 (en) 2006-07-20 2007-07-20 Electric arc furnace roof top and central portion for this roof top

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EP07786229A Active EP2047197B1 (en) 2006-07-20 2007-07-20 Electric arc furnace roof top and central portion for this roof top

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US (1) US20090168831A1 (en)
EP (2) EP1881285A1 (en)
AT (1) ATE515671T1 (en)
BR (1) BRPI0714443A2 (en)
CA (1) CA2656734A1 (en)
CO (1) CO6160252A2 (en)
MA (1) MA30647B1 (en)
MX (1) MX2009000754A (en)
WO (1) WO2008009468A1 (en)

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CN103459961A (en) * 2011-03-30 2013-12-18 现代制铁株式会社 Roof for electric furnace

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CN102252517A (en) * 2011-04-26 2011-11-23 洛阳市科创耐火材料有限公司 Combined type arc furnace top preformed piece with low cost and long service life
CN102213545A (en) * 2011-05-03 2011-10-12 张小旭 Combined arc furnace cover

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Publication number Publication date
EP2047197B1 (en) 2011-07-06
ATE515671T1 (en) 2011-07-15
US20090168831A1 (en) 2009-07-02
MA30647B1 (en) 2009-08-03
WO2008009468A1 (en) 2008-01-24
MX2009000754A (en) 2009-01-30
EP2047197A1 (en) 2009-04-15
CA2656734A1 (en) 2008-01-24
CO6160252A2 (en) 2010-05-20
BRPI0714443A2 (en) 2013-04-24

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