EP0413970B1 - Direct current arc furnace - Google Patents
Direct current arc furnace Download PDFInfo
- Publication number
- EP0413970B1 EP0413970B1 EP90113995A EP90113995A EP0413970B1 EP 0413970 B1 EP0413970 B1 EP 0413970B1 EP 90113995 A EP90113995 A EP 90113995A EP 90113995 A EP90113995 A EP 90113995A EP 0413970 B1 EP0413970 B1 EP 0413970B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- furnace
- vessel
- arc furnace
- electric
- insulating material
- 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.)
- Expired - Lifetime
Links
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B7/00—Heating by electric discharge
-
- 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
- F27D11/00—Arrangement of elements for electric heating in or on furnaces
- F27D11/08—Heating by electric discharge, e.g. arc discharge
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B7/00—Heating by electric discharge
- H05B7/02—Details
- H05B7/06—Electrodes
Definitions
- the invention relates to a direct current arc furnace with a furnace vessel which is provided with a metallic jacket, with at least one electrode connected as a cathode and at least one bottom contact, the bottom of the furnace consisting of a lining layer which is electrically conductive bricks or other equivalent Has inserts, which rests on a base plate, with which it forms the bottom contact connected as an anode, the bottom contact being insulated from the metallic jacket of the furnace vessel by insulating material.
- the invention relates to a state of the art, as it results for example from US Pat. No. 4,228,314.
- both the electrode connected as the cathode and the stove or bottom electrode, which is usually used as a contact with the ground, must B. is constructed according to US Pat. No. 4,228,314, be insulated from the metallic jacket of the furnace vessel.
- the ground contact and the adjacent parts of the bottom lining rest on a metal plate.
- This metal plate in turn lies on a layer of insulating material on the (metallic) bottom of the vessel.
- the electrical connection of the bottom contact is made via contact parts which are guided through openings in the bottom of the vessel.
- Said insulating layer is subject to high stress both by the weight of the batch and by the extreme temperatures that occur during furnace operation. Special cooling of this area is very complex.
- the invention has for its object to provide a direct current arc furnace of the type mentioned, the ground contact is optimally insulated from the vessel jacket and the insulation withstands all operating stresses.
- the base plate essentially forms the bottom of the vessel, which base plate projects beyond an inwardly projecting part of the metallic shell of the furnace vessel and is supported on it with the interposition of insulating or at least weakly electrically conductive material.
- the advantage of the invention can be seen, in particular, in the fact that the entire bottom part of the arc furnace is suspended in the furnace jacket in a quasi-floating manner and the insulation of this bottom part from the furnace jacket is easy to accomplish.
- Fig. 1 shows a direct current arc furnace with furnace vessel 1, which is provided with the usual jacket 2 made of metallic material.
- the furnace has only one electrode 3 connected as a cathode, but this number can also be 2, three or more.
- the electrode is hollow, ie the furnace is suitable for reduction purposes, but the subject matter of the invention can also be used in a melting furnace with a solid electrode connected as a cathode, usually a graphite electrode.
- slurry, coke and lime are fed through the central channel 4 in the electrode, for example for pig iron production, and an electrode spot, ie a slag-free area of the melt, is obtained in the usual way under the electrode 3.
- the furnace has a pouring spout 5 and a door hole 6.
- the ground contact consists of bricks 8, in which metallic conductors 7 are arranged.
- the conductors 7 penetrate an underlying floor lining layer 10, which in the example consists of electrically conductive carbon bricks.
- the conventional furnace lining 9 connects to the outside.
- the bricks of the floor lining layer 10 are arranged in one or more layers and lie on a bottom plate 11 shaped like a dome. This base plate 11 has a considerable extent and forms the furnace floor. It consists of steel or copper and is connected to the positive pole of the direct current source 12.
- the contact with the ground should have a large extent so that the furnace current is spread over a large part of the ground, thereby essentially preventing the arc 13 from tilting.
- the base plate 11 is provided with a cooling device 14 so that it can be kept at the lowest possible temperature and is not damaged by the heat of the furnace.
- 16 is an exhaust port for exhaust gases.
- the bricks 8 provided with conductors 7 serve as current conductors between the charge 15 and the ground contact consisting of the outer lining layer 10 and the base plate 11, which, of course, can also be designed differently. So other contact-making components can be present instead of the carbon brick.
- the jacket 2 of the furnace vessel is now drawn radially inward and forms an inwardly projecting collar 17.
- the base plate 11 overlaps the collar 17 in the radial direction.
- a ring 18 made of insulating material is arranged in the overlap area. In this way, the entire bottom part of the furnace is supported on the collar 17. The bottom part of the furnace practically floats in the furnace vessel 1.
- the electrical insulation between the furnace jacket 2 and the base plate 11 and thus the contact with the ground is accomplished via the insulating material 18.
- the upward bent end 19 of the collar 17 serves for radial centering, but does not reach the base plate.
- the edge part of the base plate 11 is provided with a compensation ring 20 which is approximately wedge-shaped in cross section.
- Either finished parts e.g. B. bricks or clinker made of refractory material loosely layered on top of one another or connected to one another by refractory mortar, or a casting or ramming compound can be used.
- the insulating material withstands the pressure loads. Furthermore, it does not have to be an isolator in the actual sense. It is sufficient if the electrical conductivity of the insulating material is at least a power of ten less than the conductivity of the ground contact in the direction of the furnace vertical axis.
- FIG. 2 The embodiment just mentioned with casting or ramming compound is illustrated in FIG. 2 for a direct current arc furnace with a different structure of the furnace shell or bottom.
- annular plate 21 is attached to the cylindrical shell 2.
- An axially extending pipe section 22 is welded to the inner circumference of this plate 21.
- the annular plate 21 corresponds to the collar 17, the tube piece 22 to the bent end 19 of the Collar 17 of Fig. 1.
- the base plate 11 is provided in its edge region with a compensating ring, which is designed here as a welded construction and has a radially extending ring 20a and an axially extending tube piece 20b.
- the pipe section 20b is extended downward beyond the plate 20a and welded to a support ring 23.
- the base plate 11 together with the parts 20a, 20b and 23 are inserted before the furnace lining is introduced and are aligned and provisionally fixed by means of insulating spacers (not shown in the drawing) relative to the furnace shell 2 and the plate 21.
- a casting or ramming mass 24, z. B. refractory concrete in the space between the vessel shell 2 and pipe section 22 and the area adjoining it upwards, in such a way that the rings 20a and 23 and the pipe section 20b are completely embedded in this mass.
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Vertical, Hearth, Or Arc Furnaces (AREA)
- Furnace Details (AREA)
- Arc Welding Control (AREA)
- Furnace Housings, Linings, Walls, And Ceilings (AREA)
- Discharge Heating (AREA)
Abstract
Description
Die Erfindung bezieht sich auf einen Gleichstrom-Lichtbogenofen mit einem Ofengefäss, das mit einem metallischen Mantel versehen ist, mit mindestens einer als Kathode geschalteten Elektrode und mindestens einem Bodenkontakt, wobei der Boden des Ofens aus einer Futterschicht besteht, welche elektrisch leitende Ziegel oder andere gleichwirkende Einsätze aufweist, welche auf einer Bodenplatte ruht, mit welcher zusammen sie den als Anode geschalteten Bodenkontakt bildet, wobei der Bodenkontakt durch Isoliermaterial vom metallischen Mantel des Ofengefässes isoliert ist.The invention relates to a direct current arc furnace with a furnace vessel which is provided with a metallic jacket, with at least one electrode connected as a cathode and at least one bottom contact, the bottom of the furnace consisting of a lining layer which is electrically conductive bricks or other equivalent Has inserts, which rests on a base plate, with which it forms the bottom contact connected as an anode, the bottom contact being insulated from the metallic jacket of the furnace vessel by insulating material.
Die Erfindung nimmt dabei Bezug auf einen Stand der Technik, wie er sich beispielsweise aus der US-Patentschrift 4,228,314 ergibt.The invention relates to a state of the art, as it results for example from US Pat. No. 4,228,314.
Bei Gleichstrom-Lichtbogenöfen müssen sowohl die als Kathode geschaltete Elektrode als auch die Herd- oder Bodenelektrode, die in der Regel als Bodenkontakt z. B. nach der US-PS 4,228,314 aufgebaut ist, vom metallischen Mantel des Ofengefässes isoliert sein. Beim bekannten Lichtbogenofen ruht der Bodenkontakt und die daran angrenzenden Teile des Bodenfutters auf einer Metallplatte. Diese Metallplatte wiederum liegt auf einer Schicht aus Isoliermaterial auf dem (metallischen) Gefässboden auf. Der elektrische Anschluss des Bodenkontakts erfolgt dabei über Kontaktteile, welche durch Oeffnungen im Gefässboden geführt sind. Die besagte Isolierschicht wird sowohl durch das Gewicht der Charge als auch durch die während des Ofenbetriebes auftretenden extremen Temperaturen hoch beansprucht. Eine besondere Kühlung dieses Bereiches ist sehr aufwendig.In direct current arc furnaces, both the electrode connected as the cathode and the stove or bottom electrode, which is usually used as a contact with the ground, must B. is constructed according to US Pat. No. 4,228,314, be insulated from the metallic jacket of the furnace vessel. In the known electric arc furnace, the ground contact and the adjacent parts of the bottom lining rest on a metal plate. This metal plate in turn lies on a layer of insulating material on the (metallic) bottom of the vessel. The electrical connection of the bottom contact is made via contact parts which are guided through openings in the bottom of the vessel. Said insulating layer is subject to high stress both by the weight of the batch and by the extreme temperatures that occur during furnace operation. Special cooling of this area is very complex.
Der Erfindung liegt die Aufgabe zugrunde, einen Gleichstrom-Lichtbogenofen der eingangs genannten Gattung zu schaffen, dessen Bodenkontakt vom Gefässmantel optimal isoliert ist und die Isolation allen Betriebsbeanspruchungen standhält.The invention has for its object to provide a direct current arc furnace of the type mentioned, the ground contact is optimally insulated from the vessel jacket and the insulation withstands all operating stresses.
Diese Aufgabe wird erfindungsgemäss dadurch gelöst, dass die genannte Bodenplatte im wesentlichen den Gefässboden bildet, welche Bodenplatte einen nach innen vorspringenden Teil des metallischen Mantels des Ofengefässes überragt und sich unter Zwischenschaltung von isolierendem oder zumindest elektrisch schwach leitendem Material darauf abstützt.This object is achieved according to the invention in that the base plate essentially forms the bottom of the vessel, which base plate projects beyond an inwardly projecting part of the metallic shell of the furnace vessel and is supported on it with the interposition of insulating or at least weakly electrically conductive material.
Der Vorteil der Erfindung ist insbesondere darin zu sehen, dass die gesamte Bodenpartie des Lichtbogenofens quasi schwimmend im Ofenmantel aufgehängt ist und die Isolierung dieser Bodenpartie vom Ofenmantel einfach zu bewerkstelligen ist.The advantage of the invention can be seen, in particular, in the fact that the entire bottom part of the arc furnace is suspended in the furnace jacket in a quasi-floating manner and the insulation of this bottom part from the furnace jacket is easy to accomplish.
Ausführungsbeispiele der Erfindung sowie die damit erzielbaren Vorteile werden nachfolgend anhand der Zeichnung näher erläutert.Exemplary embodiments of the invention and the advantages which can be achieved thereby are explained in more detail below with reference to the drawing.
In der Zeichnung sind Ausführungsbeispiele der Erfindung schematisch dargestellt, und zwar zeigt:
- Fig.1
- ein erstes Ausführungsbeispiel eines Gleichstrom-Lichtbogenofen gemäss der Erfindung in Seitenansicht;
- Fig.2
- ein Detail der Abstützung und Isolierung der Bodenpartie bei einem anderen Ofengefässtyp;
- Fig. 1
- a first embodiment of a DC arc furnace according to the invention in side view;
- Fig. 2
- a detail of the support and insulation of the bottom part in another type of furnace;
Fig. 1 zeigt einen Gleichstrom-Lichtbogenofen mit Ofengefäss 1, das mit dem üblichen Mantel 2 aus metallischen Material versehen ist. Im Ausführungsbeispiel weist der Ofen nur eine als Kathode geschaltete Elektrode 3 auf, doch kann diese Zahl auch 2, drei oder mehr betragen. Im Ausführungsbeispiel ist ist Elektrode hohl ausgebildet, d.h. der Ofen ist für Reduktionszwecke geeignet, doch ist der Erfindungsgegenstand auch bei einem Schmelzofen mit massiver als Kathode geschalteter Elektrode, normalerweise Grafit-Elektrode, anwendbar.
Im Reduktionsfall wird durch den zentralen Kanal 4 in der Elektrode, beispielsweise für die Roheisenherstellung, Schlich, Koks und Kalk zugeführt, und unter der Elektrode 3 erhält man auf übliche Weise einen Elektrodenfleck, d.h. eine schlackenfreie Fläche der Schmelze. Der Ofen hat wie üblich eine Giess-Schnauze 5 und ein Türloch 6. Im Ofengrund ist ein Bodenkontakt angebracht. Der Bodenkontakt besteht aus Ziegeln 8, in denen metallische Leiter 7 angeordnet sind. Die Leiter 7 dringen in eine darunterliegende Bodenfutterschicht 10 ein, die im Beispielsfall aus elektrisch leitenden Kohlenstoff- Ziegeln besteht. Nach aussen hin schliesst sich die konventionelle Ofenausmauerung 9 an. Die Ziegel der Bodenfutterschicht 10 sind in einer oder in mehreren Lagen angeordnet und liegen auf einer kallottenartig geformten Bodenplatte 11 auf. Diese Bodenplatte 11 hat eine erhebliche Ausdehnung und bildet den Ofenboden. Sie besteht aus Stahl oder Kupfer und wird an den positiven Pol der Gleichstromquelle 12 angeschlossen. Der Bodenkontakt soll eine grosse Erstreckung haben, damit eine Ausbreitung des Ofenstroms über einen grossen Teil des Bodens erzielt wird, wodurch eine Schrägstellung des Lichtbogens 13 im wesentlichen verhindert wird. Die Bodenplatte 11 ist mit einer Kühleinrichtung 14 versehen, damit sie auf möglichst niedriger Temperatur gehalten werden kann und nicht durch die Hitze des Ofens beschädigt wird. 16 ist eine Absaugöffnung für Abgase.
Die mit Leitern 7 versehenen Ziegel 8 dienen als Stromleiter zwischen der Charge 15 und dem aus Aussenfutterschicht 10 und der Bodenplatte 11 bestehenden Bodenkontakt, der, natürlich auch anders ausgeführt sein kann. So können statt der Kohlenstoff-Ziegel andere Kontakt gebende Bauteile vorhanden sein.Fig. 1 shows a direct current arc furnace with furnace vessel 1, which is provided with the
In the event of a reduction, slurry, coke and lime are fed through the central channel 4 in the electrode, for example for pig iron production, and an electrode spot, ie a slag-free area of the melt, is obtained in the usual way under the electrode 3. As usual, the furnace has a
The
Insoweit entspricht der Gleichstrom-Lichtbogenofen dem Stand der Technik und ist ausführlich in dem eingangs genannten US-Patent 4,228,314 oder auch der DE-Patentschrift 30 22 566 ausführlich beschrieben.To this extent, the direct current arc furnace corresponds to the prior art and is described in detail in the above-mentioned US Pat. No. 4,228,314 or also in DE Pat. No. 30 22 566.
Erfindungsgemäss ist nun der Mantel 2 des Ofengefässes radial nach innen gezogen und bildet einen nach innen ragenden Kragen 17. Die Bodenplatte 11 überlappt den Kragen 17 in radialer Richtung. Im Ueberlappungsbereich ist eines Ring 18 aus Isoliermaterial angeordnet. Auf diese Weise stützt sich die gesamte Bodenpartie des Ofens auf dem Kragen 17 ab. Die Bodenpartie des Ofens schwimmt quasi im Ofengefäss 1. Gleichzeitig wird über das Isoliermaterial 18 die elektrische Isolation zwischen Ofenmantel 2 und Bodenplatte 11 und damit dem Bodenkontakt bewerkstelligt.According to the invention, the
Zur radialen Zentrierung dient das nach oben umgebogene Ende 19 des Kragens 17, das jedoch nicht bis an die Bodenplatte heranreicht. Um die Einleitung der Kräfte auf das Isoliermaterial übersichtlich zu gestalten, ist die Randpartie der Bodenplatte 11 mit einem im Querschnitt etwa keilförmig gestalteten Ausgleichsring 20 versehen.The
Als Isoliermaterial können entweder Fertigteile, z. B. Ziegel oder Klinker aus feuerfestem Material lose aufeinander geschichtet oder durch feuerfesten Mörtel untereinander verbunden, oder eine Giess- oder Stampfmasse verwendet werden. Wesentlich ist dabei neben der geringen elektrischen Leitfähigkeit, dass das Isoliermaterial den Druckbeanspruchungen standhält. Es muss ferner kein Isolator im eigentlichen Sinn sein. Es genügt, wenn die elektrische Leitfähigkeit des Isoliermaterials um mindestens eine Zehnerpotenz kleiner ist als die Leitfähigkeit des Bodenkontakts in Richtung der Ofen-Hochachse.Either finished parts, e.g. B. bricks or clinker made of refractory material loosely layered on top of one another or connected to one another by refractory mortar, or a casting or ramming compound can be used. In addition to the low electrical conductivity, it is essential that the insulating material withstands the pressure loads. Furthermore, it does not have to be an isolator in the actual sense. It is sufficient if the electrical conductivity of the insulating material is at least a power of ten less than the conductivity of the ground contact in the direction of the furnace vertical axis.
Die soeben angesprochene Ausführungsform mit Gies- oder Stampfmasse ist in Fig.2 bei einem Gleichstrom-Lichtbogenofen mit anderem Aufbau des Ofenmantels bzw. Boden verdeutlicht.The embodiment just mentioned with casting or ramming compound is illustrated in FIG. 2 for a direct current arc furnace with a different structure of the furnace shell or bottom.
Am zylindrischen Kesselmantel 2 ist eine ringförmige Platte 21 befestigt. Am inneren Umfang dieser Platte 21 ist eine axial verlaufendes Rohrstück 22 angeschweisst. Hinsichtlich ihrer Funktion entspricht dabei die ringförmige Platte 21 dem Kragen 17, das Rohrstück 22 dem umgebogenen Ende 19 des Kragens 17 von Fig .1. Analog Fig. 1 ist die Bodenplatte 11 in ihrem Randbereich mit einem Ausgleichsring versehen, der hier als Schweisskonstruktion ausgebildet ist und einen radial verlaufenden Ring 20a und ein axial verlaufendes Rohrstück 20b aufweist. Das Rohrstück 20b ist über die Platte 20a nach unten hinaus verlängert und mit einem Stützring 23 verschweisst.An
Im Zuge der Herstellung des Ofens wird vor dem Einbringen der Ofenausmauerung die Bodenplatte 11 mitsamt den Teile 20a,20b und 23 eingesetzt und mittels (in der Zeichnung nicht dargestellten) isolierenden Abstandhaltern gegenüber dem Ofenmantel 2 und der Platte 21 ausgerichtet und provisorisch fixiert. Dann wird eine Giess- oder Stampfmasse 24, z. B. Feuerfestbeton in den Raum zwischen Gefässmantel 2 und Rohrstück 22 und den sich nach oben daran anschliessenden Bereich eingefüllt, und zwar derart, dass die Ringe 20a und 23 und das Rohrstück 20b vollständig in diese Masse eingebettet sind. Daran schliesst sich der weitere Aufbau des Ofens in bekannter Weise an.In the course of the manufacture of the furnace, the
- 11
- OfengefässOven vessel
- 22nd
- GefässmantelVessel jacket
- 33rd
- Elektrodeelectrode
- 44th
- Kanal in 3Channel in 3rd
- 55
- Giess-SchnauzePouring snout
- 66
- SchürlochPoker hole
- 77
- Leiter in 8Head in 8
- 88th
- Ziegelbrick
- 99
- OfenausmauerungKiln lining
- 1010th
- BodenfutterschichtFloor lining layer
- 1111
- BodenplatteBase plate
- 1212
- GleichstromquelleDC power source
- 1313
- LichtbogenElectric arc
- 1414
- KühleinrichtungCooling device
- 1515
- ChargeBatch
- 1616
- AbsaugöffnungSuction opening
- 1717th
- Kragencollar
- 1818th
- Isoliermaterialinsulating material
- 1919th
- umgebogenes Ende von 17bent end of 17th
- 2020th
- AusgleichsringCompensation ring
- 20a, 21, 2320a, 21, 23
- ringförmige Plattenannular plates
- 20b, 2220b, 22
- RohrstückePipe pieces
- 2424th
- Feuerfest-BetonRefractory concrete
Claims (7)
- Direct-current electric-arc furnace having a furnace vessel (1), which is surrounded by a metallic shell (2), at least one electrode (3) connected as cathode, and at least one bottom contact (7,8,11), the bottom of the furnace consisting of a lining layer which has electrically conductive bricks or other identically acting inserts, which lining layer rests on a bottom plate (11) together with which it forms the bottom contact connected as anode, the bottom contact being insulated from the metallic shell (2) of the furnace vessel (1) by insulating material (18;24), characterised in that said bottom plate (11) essentially forms the vessel bottom, the bottom plate (11) overlaps a part (17;21), projecting to the inside, of the metallic shell (2) of the furnace vessel (1) and, with an insulating material (18;24), or a material (18;24) which is at least a poor electrical conductor, inbetween, is supported thereon.
- Electric-arc furnace according to Claim 1, characterised in that the part (17) projecting to the inside is connected in one piece to the vessel shell (2).
- Electric-arc furnace according to Claim 1, characterised in that the part projecting to the inside is an annular plate (21) which is firmly connected to the lower shell end.
- Electric-arc furnace according to Claim 2 or 3, characterised in that the bottom plate (11) is designed approximately in the shape of a spherical surface and is provided in its marginal area with a compensating ring (20;20a).
- Electric-arc furnace according to one of Claims 1 to 4, characterised in that the insulating material consists of individual building blocks, in particular refractory bricks or clinkers which are either arranged loosely in layers or are connected to one another by a refractory mortar.
- Electric-arc furnace according to one of Claims 1 to 4, characterised in that the insulating material is a casting or ramming mass of refractory material, in particular refractory concrete.
- Electric-arc furnace according to one of Claims 1 to 6, characterised in that the electrical conductivity of the insulating material is less than the conductivity of the bottom contact (7,8,11) in the direction of the vertical axis of the furnace by at least a power of ten.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT90113995T ATE94716T1 (en) | 1989-08-21 | 1990-07-21 | DC ARC FURNACE. |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH3027/89A CH678785A5 (en) | 1989-08-21 | 1989-08-21 | |
| CH3027/89 | 1989-08-21 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0413970A1 EP0413970A1 (en) | 1991-02-27 |
| EP0413970B1 true EP0413970B1 (en) | 1993-09-15 |
Family
ID=4246996
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP90113995A Expired - Lifetime EP0413970B1 (en) | 1989-08-21 | 1990-07-21 | Direct current arc furnace |
Country Status (12)
| Country | Link |
|---|---|
| EP (1) | EP0413970B1 (en) |
| JP (1) | JPH0762585B2 (en) |
| KR (1) | KR0172120B1 (en) |
| CN (1) | CN1019141B (en) |
| AT (1) | ATE94716T1 (en) |
| BR (1) | BR9004099A (en) |
| CA (1) | CA2023041A1 (en) |
| CH (1) | CH678785A5 (en) |
| DE (1) | DE59002718D1 (en) |
| ES (1) | ES2046611T3 (en) |
| RU (1) | RU1784089C (en) |
| ZA (1) | ZA906533B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2633466T3 (en) * | 2009-03-31 | 2017-09-21 | Sms Group S.P.A. | Electric arc furnace |
| CN106091671A (en) * | 2016-07-12 | 2016-11-09 | 上海彭浦特种耐火材料厂有限公司 | Electrode structure and application thereof |
| CN107354320B (en) * | 2017-09-17 | 2023-06-27 | 贵州明峰工业废渣综合回收再利用有限公司 | High-efficient zinc powder production facility |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1369578A (en) * | 1919-10-01 | 1921-02-22 | Ludlum Electric Furnace Corp | Electric furnace |
| FR670019A (en) * | 1928-06-07 | 1929-11-23 | Improvements to electric ovens | |
| FR2188812A5 (en) * | 1972-06-09 | 1974-01-18 | Schlienger Max | Rotating electrode whell arc furnace - has arc positioning system |
| SE452690B (en) * | 1983-07-07 | 1987-12-07 | Asea Ab | DC arc furnace |
| FR2577311B1 (en) * | 1985-02-11 | 1987-03-06 | Siderurgie Fse Inst Rech | ELECTRICAL CONNECTION DEVICE FOR PLACING ON THE WALL OF A DIRECT CURRENT METALLURGICAL OVEN. |
| DE3535690A1 (en) * | 1985-10-05 | 1987-04-09 | Gutehoffnungshuette Man | CONTACT ELECTRODE ARRANGEMENT FOR DC ARC OR RESISTANCE MELTING STOVE |
-
1989
- 1989-08-21 CH CH3027/89A patent/CH678785A5/de not_active IP Right Cessation
-
1990
- 1990-07-21 ES ES199090113995T patent/ES2046611T3/en not_active Expired - Lifetime
- 1990-07-21 EP EP90113995A patent/EP0413970B1/en not_active Expired - Lifetime
- 1990-07-21 DE DE90113995T patent/DE59002718D1/en not_active Expired - Lifetime
- 1990-07-21 AT AT90113995T patent/ATE94716T1/en not_active IP Right Cessation
- 1990-08-09 CA CA002023041A patent/CA2023041A1/en not_active Abandoned
- 1990-08-17 ZA ZA906533A patent/ZA906533B/en unknown
- 1990-08-20 RU SU904831032A patent/RU1784089C/en active
- 1990-08-20 BR BR909004099A patent/BR9004099A/en not_active IP Right Cessation
- 1990-08-21 CN CN90107301A patent/CN1019141B/en not_active Expired
- 1990-08-21 JP JP2218274A patent/JPH0762585B2/en not_active Expired - Lifetime
- 1990-08-21 KR KR1019900012879A patent/KR0172120B1/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0762585B2 (en) | 1995-07-05 |
| KR910005727A (en) | 1991-03-30 |
| EP0413970A1 (en) | 1991-02-27 |
| DE59002718D1 (en) | 1993-10-21 |
| BR9004099A (en) | 1991-09-03 |
| JPH0395387A (en) | 1991-04-19 |
| ATE94716T1 (en) | 1993-10-15 |
| CA2023041A1 (en) | 1991-02-22 |
| ZA906533B (en) | 1991-07-31 |
| KR0172120B1 (en) | 1999-05-01 |
| CN1049714A (en) | 1991-03-06 |
| CH678785A5 (en) | 1991-10-31 |
| RU1784089C (en) | 1992-12-23 |
| ES2046611T3 (en) | 1994-02-01 |
| CN1019141B (en) | 1992-11-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| DE2905553C2 (en) | ||
| DE3022566C2 (en) | ||
| DE2950890C2 (en) | ||
| GB2042309A (en) | Dc arc furnace | |
| EP0151415B1 (en) | Direct current arc furnace or direct current arc ladle | |
| DE3413745C2 (en) | DC arc furnace | |
| DE7727148U1 (en) | COMPOSED ELECTRODE FOR ARC FURNACES | |
| EP0473809B1 (en) | Direct-current arc furnace | |
| EP0413970B1 (en) | Direct current arc furnace | |
| EP0589150B1 (en) | Bottom electrode for direct current arc furnaces | |
| DE3409255C2 (en) | ||
| EP0125200B1 (en) | Furnace vessel for a direct current arc furnace | |
| EP0541044B1 (en) | DC arc furnace | |
| DE3534750A1 (en) | FLOOR OF AN ELECTRICALLY HEATED MELTING STOVE, ESPECIALLY A DC STOVE | |
| EP0422406A2 (en) | Anode for direct current arc furnace | |
| DE3742861C1 (en) | Metallurgical vessel | |
| EP0518070B1 (en) | Direct current arc furnace facility | |
| EP0530534B1 (en) | Lining for a direct-current arc furnace | |
| DE3242209C2 (en) | ||
| DE861750C (en) | Electrolytic cell | |
| DE2847946C2 (en) | DC powered arc furnace | |
| EP0753077B1 (en) | Dc-heated metallurgical vessel with base electrode | |
| DE2159667C3 (en) | ||
| DE3840827A1 (en) | ELECTROTHERMIC REDUCTION STOVES | |
| DE3213465A1 (en) | ARC FURNACE |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE CH DE ES FR GB IT LI NL SE |
|
| 17P | Request for examination filed |
Effective date: 19910717 |
|
| 17Q | First examination report despatched |
Effective date: 19930119 |
|
| GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
| AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE CH DE ES FR GB IT LI NL SE |
|
| REF | Corresponds to: |
Ref document number: 94716 Country of ref document: AT Date of ref document: 19931015 Kind code of ref document: T |
|
| REF | Corresponds to: |
Ref document number: 59002718 Country of ref document: DE Date of ref document: 19931021 |
|
| ITF | It: translation for a ep patent filed |
Owner name: DE DOMINICIS & MAYER S. |
|
| GBT | Gb: translation of ep patent filed (gb section 77(6)(a)/1977) |
Effective date: 19931122 |
|
| ET | Fr: translation filed | ||
| REG | Reference to a national code |
Ref country code: ES Ref legal event code: FG2A Ref document number: 2046611 Country of ref document: ES Kind code of ref document: T3 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19940613 Year of fee payment: 5 |
|
| PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19940731 Year of fee payment: 5 |
|
| 26N | No opposition filed | ||
| EAL | Se: european patent in force in sweden |
Ref document number: 90113995.6 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Effective date: 19950721 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19960201 |
|
| GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19950721 |
|
| NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee |
Effective date: 19960201 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 19970623 Year of fee payment: 8 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 19970624 Year of fee payment: 8 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: ES Payment date: 19970718 Year of fee payment: 8 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 19970722 Year of fee payment: 8 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF THE APPLICANT RENOUNCES Effective date: 19980722 Ref country code: SE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980722 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980731 Ref country code: BE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980731 Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980731 |
|
| BERE | Be: lapsed |
Owner name: ASEA BROWN BOVERI A.G. Effective date: 19980731 |
|
| REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
| EUG | Se: european patent has lapsed |
Ref document number: 90113995.6 |
|
| REG | Reference to a national code |
Ref country code: FR Ref legal event code: TP |
|
| REG | Reference to a national code |
Ref country code: ES Ref legal event code: FD2A Effective date: 20001009 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20090716 Year of fee payment: 20 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20090722 Year of fee payment: 20 Ref country code: AT Payment date: 20090715 Year of fee payment: 20 |
|
| PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20090723 Year of fee payment: 20 |
|
| PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION Effective date: 20100721 |