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EP0167475A1 - Direct current arc heating device - Google Patents

Direct current arc heating device Download PDF

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Publication number
EP0167475A1
EP0167475A1 EP85730024A EP85730024A EP0167475A1 EP 0167475 A1 EP0167475 A1 EP 0167475A1 EP 85730024 A EP85730024 A EP 85730024A EP 85730024 A EP85730024 A EP 85730024A EP 0167475 A1 EP0167475 A1 EP 0167475A1
Authority
EP
European Patent Office
Prior art keywords
heating device
electrode
vessel
metal electrode
melting 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.)
Granted
Application number
EP85730024A
Other languages
German (de)
French (fr)
Other versions
EP0167475B1 (en
Inventor
Friedrich Dr. Ing. Nordmeyer
Eckard Schunk
Frank Winter
C. L. Jackson
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.)
Vodafone GmbH
Original Assignee
Mannesmann AG
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 Mannesmann AG filed Critical Mannesmann AG
Publication of EP0167475A1 publication Critical patent/EP0167475A1/en
Application granted granted Critical
Publication of EP0167475B1 publication Critical patent/EP0167475B1/en
Expired legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B7/00Heating by electric discharge
    • H05B7/02Details
    • H05B7/06Electrodes
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B7/00Heating by electric discharge
    • H05B7/02Details
    • H05B7/10Mountings, supports, terminals or arrangements for feeding or guiding electrodes

Definitions

  • the contact electrode and the graphite electrode can easily be removed from the vessel and used for another interchangeable vessel.
  • the process of the metallurgical process can thus be accelerated without increasing costs.
  • the radiation exposure of the ff material is significantly reduced by the arrangement of the electrodes according to the invention. Operating costs are reduced due to smaller electrode consumption.
  • the device is also suitable for vacuum processes and processes with protective gas cover.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Furnace Details (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Discharge Heating (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)

Abstract

Gleichstrom-Lichtbogen-Heizvorrichtung, insbesondere Pfanne oder Pfannenofen, mit mindestens einer aufzehrenden, mit dem im Gefäß befindlichen Schmelzgut in Kontakt stehenden Metallelektrode (3) sowie einer über dem Schmelzgut höhenverstellbar angeordneten Graphit-Elektrode, wobei zwischen der Graphit-Elektrode und dem Schmelzgut ein Lichtbogen entwickelt wird. Die Metallelektrode (3) (Metallektroden) ist (sind) in einer oberhalb des Gefässes (1) vorgesehenen Haltevorrichtung nachführbar angeordnet.Direct-current arc heating device, in particular pan or ladle furnace, with at least one consumable metal electrode (3) which is in contact with the melting material in the vessel and a graphite electrode which is arranged to be height-adjustable above the melting material, with an interposed between the graphite electrode and the melting material Arc is developed. The metal electrode (3) (metal electrodes) is (are) arranged in a holding device provided above the vessel (1).

Description

Die Erfindung betrifft eine Heizvorrichtung gemäß dem Oberbegriff des Anspruchs 1.The invention relates to a heating device according to the preamble of claim 1.

Bei Öfen dieser Art Ist üblicherweise eine Graphitelektrode als Kathode geschaltet, während die Kontaktelektroden als Anoden arbeiten.In furnaces of this type, a graphite electrode is usually connected as the cathode, while the contact electrodes work as anodes.

Aus der DE-OS 31 07 454 ist ein Pfannenofen für Gleichstrom bekannt, der eine als Kathode arbeitende Lichtbogenelektrode aufweist. In dem bodennahen Bereich des Pfannengefäßes sind Kontaktblöcke aus einem Metall vorgesehen. Die Kontaktblöcke sind an der der Pfannenachsenmitte zugewandten Seite mit feuerfesten Steinen mit leitenden Einlagen versehen.From DE-OS 31 07 454 a ladle furnace for direct current is known which has an arc electrode working as a cathode. Contact blocks made of a metal are provided in the region of the pan vessel near the bottom. The contact blocks are provided with refractory stones with conductive inserts on the side facing the middle of the pan axis.

Durch diese Vorrichtung mit seitlich angeschlossenen Kontaktelektroden sollte der Vorteil erreicht werden, daß der Boden für Bodenabstichlöcher freibleibt. Diese Vorrichtung ist jedoch mit dem Nachteil behaftet, daß bei Verbrauch oder Beschädigung der mit dem Gefäß fest verbundenen Kontaktblöcke die Erneuerungsarbeiten sehr schwierig und aufwendig sind.This device with laterally connected contact electrodes should achieve the advantage that the floor remains free for floor tapping holes. However, this device has the disadvantage that the renewal work is very difficult and expensive when the contact blocks which are firmly connected to the vessel are used or damaged.

Aufgabe der Erfindung ist es, eine Gleichstrom-Lichtbogen-Heizvorrichtung der eingangs genannten Art zu schaffen, deren Kontaktelektroden in vertikaler sowie horizontaler Richtung beweglich sind, wobei die Reparatur- oder Erneuerungsarbeiten an den Elektroden wesentlich leichter als bisher durchführbar sind. Außerdem soll durch die Erfindung ermöglicht werden, die Elektroden für verschiedene wechselbare Gefäße zu benutzen.The object of the invention is to provide a direct-current arc heating device of the type mentioned, the contact electrodes of which can be moved in the vertical and horizontal directions, the repair or renewal work on the electrodes being able to be carried out much more easily than hitherto. In addition, the invention is intended to enable the electrodes to be used for different interchangeable vessels.

Diese Aufgabe wird durcn die Erflndunssmerkmale des Hauptanspruchs gelöst. Vorteilhafte Weiterbildungen der Erfindung ergeben sich aus den Unteransprüchen.This task is solved by the invention features of the main claim. Advantageous developments of the invention result from the subclaims.

Nach der Erfindung ist es möglich, die Eintauchtiefe der oberhalb des Gefäßes nachführbar angeordneten Kontaktelektrode nach den Erfordernissen des Betriebes zu regeln.According to the invention, it is possible to regulate the immersion depth of the contact electrode arranged above the vessel according to the requirements of the operation.

Die Kontaktelektrode sowie die Graphitelektrode können leicht aus dem Gefäß entfernt und für ein anderes Wechselgefäß eingesetzt werden. Damit kann der Ablauf des metallurgischen Prozesses ohne Kostensteigerung beschleunigt werden.The contact electrode and the graphite electrode can easily be removed from the vessel and used for another interchangeable vessel. The process of the metallurgical process can thus be accelerated without increasing costs.

Durch die unmittelbare innere Kühlung der Elektrode kann ihre Standzeit wesentlich verlängert werden.Due to the immediate internal cooling of the electrode, its service life can be significantly extended.

Die größte thermische Beanspruchung der Kontaktelektrode entsteht bekanntlich an ihren Kontaktflächen mit dem flüssigen Schmelzbad. Deshalb kann die erfindungsgemäße Elektrode in ihrem unteren, mit der Schlacke in Berührung stehenden Bereich mit einem thermischen Schutz versehen werden.As is well known, the greatest thermal stress on the contact electrode arises at its contact surfaces with the liquid weld pool. The electrode according to the invention can therefore be provided with thermal protection in its lower region which is in contact with the slag.

Durch die erfindungsgenäße Anordnung der Elektroden wird die Strahlungsbelastung des ff-Materials wesentlich vermindert. Durch einen kleineren Elektrodenverbrauch werden die Betriebskosten verringert. Die Vorrichtung Ist auch für Vakuumverfahren sowie Verfahren mit Schutzgasabdeckung geeignet.The radiation exposure of the ff material is significantly reduced by the arrangement of the electrodes according to the invention. Operating costs are reduced due to smaller electrode consumption. The device is also suitable for vacuum processes and processes with protective gas cover.

Die Erfindung wird anhand der beigefügten schematischen Zeichnung näher erläutert.The invention is explained in more detail with reference to the attached schematic drawing.

Über dem Ofengefäß 1 sind eine Graphitelektrode 2 sowie eine Kontaktelektrode 3 aus Metall, in dem gezeichneten Beispiel aus Stahl, an einem gemeinsamen Tragarm 4 befestigt. Die Graphit- elektrode 2 ist in einer Nachsetzvorrichtung 5 verspannt, während die Nachführvorrichtung für die Kontaktelektrode 3 mit 6 bezeichnet ist. Bei den Nachsetzvorrichtungen, die z.B. aus der DE-PS 21 25 773 bekannt sind, handelt es sich um gängige Ausführungen.A graphite electrode 2 and a contact electrode 3 made of metal, in the illustrated example made of steel, are fastened to a common support arm 4 above the furnace vessel 1. The graphite electrode 2 is clamped in a repositioning device 5 during the tracking device for the contact electrode 3 is designated 6. The repositioning devices, which are known for example from DE-PS 21 25 773, are common designs.

In einer anderen, nicht dargestellten Ausführung können für die Graphit-Elektrode 2 und für die Kontaktelektrode 3 getrennte Tragarme vorgesehen werden.In another embodiment, not shown, separate support arms can be provided for the graphite electrode 2 and for the contact electrode 3.

Der Tragarm 4 ist mit einer positionsgeregelten Führungssäule 7 fest verbunden und somit samt beider Elektroden mit Hilfe des hydraulischen Zylinders 8 höhenverstellbar.The support arm 4 is firmly connected to a position-controlled guide column 7 and thus, together with both electrodes, can be adjusted in height by means of the hydraulic cylinder 8.

Zum Wechsel der Pfanne können beide Elektroden angehoben und aus dem Gefäß entfernt werden.To change the pan, both electrodes can be raised and removed from the vessel.

Die Graphitelektrode 2 wird so geregelt, daß der Lichtbogenofen aufrechterhalten bleibt.The graphite electrode 2 is controlled so that the arc furnace is maintained.

Die Kontaktelektrode 2 taucht in die Schmelze 10 ein. Die Nachführvorrichtung 6 sorgt dafür, daß ein ausreichender Kontakt mit der Schmelze 10 gewährleistet wird.The contact electrode 2 is immersed in the melt 10. The tracking device 6 ensures that sufficient contact with the melt 10 is ensured.

Mit 11 ist die Schlackenschicht bezeichnet.The slag layer is designated by 11.

In dem dargestellten Beispiel besitzt die Kontaktelektrode 3 axiale Bohrungen 12, die eine intensive Kühlung (z.B. durch Kühlgase, wie Argon) der Elektrode ermöglichen.In the example shown, the contact electrode 3 has axial bores 12, which allow intensive cooling (e.g. by cooling gases, such as argon) of the electrode.

Die Heizvorrichtung kann sowohl stationär als auch auf einem Pfannentransportwagen betrieben werden.The heater can be operated both stationary and on a ladle trolley.

Claims (7)

1. Gleichstrom-Lichtbogen-Heizvorrichtung, insbesondere Pfanne oder Pfannenofen, mit mindestens einer aufzehrenden, mit dem im Gefäß befindlichen Schmelzgut in Kontakt stehenden Metallelektrode sowie einer über dem Schmelzgut höhenverstellbar angeordneten Graphit- Elektrode wobei zwischen der Graphit-Elektrode und dem Schmelzgut ein Lichtbogen entwickelt wird,
dadurch gekennzeichnet,
daß die Metallelektrode (3) (Metallelektroden) in einer oberhalb des Gefäßes (1) vorgesehenen Haltevorrichtung nachführbar angeordnet ist (sind).
1. DC electric arc heating device, in particular pan or ladle furnace, with at least one consumable metal electrode which is in contact with the melting material in the vessel and a graphite electrode which is vertically adjustable above the melting material, an arc being developed between the graphite electrode and the melting material becomes,
characterized,
that the metal electrode (3) (metal electrodes) is (are) arranged in a holding device provided above the vessel (1).
2. Heizvorrichtung nach Anspruch 1,
dadurch gekennzeichnet,
daß die Haltevorrichtung ein mit einer parallel zur Gefäßachse angeordneten Führungssäule (7) verbundener Tragarm (4) ist.
2. Heating device according to claim 1,
characterized,
that the holding device is a support arm (4) connected to a guide column (7) arranged parallel to the vessel axis.
3. Heizvorrichtung nach Anspruch 2,
dadurch gekennzeichnet,
daß am Tragarm (4) eine Nachführvorrichtung (6) für die Metallelektrode (3) angeordnet ist.
3. Heater according to claim 2,
characterized,
that a tracking device (6) for the metal electrode (3) is arranged on the support arm (4).
4. Heizvorrichtung nach Anspruch 3,
dadurch gekennzeichnet,
daß die Nachführvorrichtung (6) mit einer der Abschmelzgeschwindigkeit entsprechend arbeitenden Steuervorrichtung steuerbar ist.
4. Heating device according to claim 3,
characterized,
that the tracking device (6) can be controlled with a control device operating in accordance with the melting speed.
5. Heizvorrichtung nach den Ansprüchen 1 bis 4,
dadurch gekennzeichnet,
daß die Metallelektrode (3) sowie die Graphit-Elektrode (2) in einem einzigen gemeinsamen Tragann (4) angeordnet sind.
5. Heating device according to claims 1 to 4,
characterized,
that the metal electrode (3) and the graphite electrode (2) are arranged in a single common carrier (4).
6. Heizvorrichtung nach Anspruch 5,
dadurch gekennzeichnet,
daß der mit der Führungssäule (7) verbundene Tragarm (4) auf einem verfahrbaren Gestell angeordnet ist.
6. Heating device according to claim 5,
characterized,
that the support arm (4) connected to the guide column (7) is arranged on a movable frame.
7. Heizvorrichtung nach den Ansprüchen 1 bis 6,
dadurch gekennzeichnet,
daß die Metallelektrode (3) kühlbar ausgeführt ist.
7. Heating device according to claims 1 to 6,
characterized,
that the metal electrode (3) is coolable.
EP85730024A 1984-05-24 1985-02-18 Direct current arc heating device Expired EP0167475B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19843419681 DE3419681A1 (en) 1984-05-24 1984-05-24 DC CURRENT ARC HEATING DEVICE
DE3419681 1984-05-24

Publications (2)

Publication Number Publication Date
EP0167475A1 true EP0167475A1 (en) 1986-01-08
EP0167475B1 EP0167475B1 (en) 1989-12-27

Family

ID=6236920

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85730024A Expired EP0167475B1 (en) 1984-05-24 1985-02-18 Direct current arc heating device

Country Status (7)

Country Link
US (1) US4646318A (en)
EP (1) EP0167475B1 (en)
JP (1) JPS60254592A (en)
BR (1) BR8502426A (en)
DE (2) DE3419681A1 (en)
DK (1) DK163402C (en)
ES (1) ES295801Y (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4964114A (en) * 1986-11-26 1990-10-16 Mannesmann Ag Electrode positioning mechanism
DE3808683C1 (en) * 1988-03-11 1989-09-07 Mannesmann Ag, 4000 Duesseldorf, De
JP2794774B2 (en) * 1989-05-09 1998-09-10 大同特殊鋼株式会社 Operation method of DC arc furnace
DE4108583C2 (en) * 1991-03-14 1997-06-05 Mannesmann Ag Device for coupling the power supply to a metallurgical vessel
US5539768A (en) * 1995-03-21 1996-07-23 Ltv Steel Company, Inc. Electric arc furnace electrode consumption analyzer
MX2012006010A (en) * 2009-11-25 2013-01-29 Fundacion Tecnalia Res & Innovation Inoculation procedure and device.
JPWO2011096170A1 (en) * 2010-02-08 2013-06-10 株式会社大紀アルミニウム工業所 Aluminum purification method and apparatus
CN114477736B (en) * 2022-03-25 2023-10-10 锦州佑鑫石英科技有限公司 Manufacturing method of high-quality quartz crucible

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1333950A (en) * 1916-03-24 1920-03-16 Ludlum Electric Furnace Corp Electric furnace
FR846004A (en) * 1939-09-07
US3709997A (en) * 1970-12-20 1973-01-09 J Alferov Convertible electrode electric furnace installation and method
FR2197988A1 (en) * 1972-08-29 1974-03-29 Nipkti Po Cherna Metalurgia
DE2355168A1 (en) * 1972-11-17 1974-05-30 Allmaenna Svenska Elek Ska Ab MELTING PROCESS FOR ARC FURNACE USING DC CURRENT AND ARC FURNACE FOR PERFORMING THE PROCESS
DE3232551A1 (en) * 1981-12-01 1983-06-09 Iso "Metalurgkomplekt", Sofija METHOD AND DEVICE FOR TREATING AND REFINING LIQUID METAL ALLOYS BY MEANS OF DC-ARC HEATING

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3612740A (en) * 1968-01-08 1971-10-12 Huta Zabrze Arrangement for production of metal alloys steel alloys in particular
US3612739A (en) * 1970-02-05 1971-10-12 Simon M Korneff Dual electric furnace facility
DE2125773C3 (en) * 1971-05-25 1979-12-20 Demag Ag, 4100 Duisburg Deep electrode holder for electric arc and reduction furnaces
SE376634C (en) * 1972-05-02 1985-10-28 Nipkti Cherna Metalurgia SET TO MANUFACTURE STEEL MEDIUM DC AND OVEN FOR IMPLEMENTATION OF THE SET
SE382828B (en) * 1974-06-24 1976-02-16 Asea Ab METHOD OF MANUFACTURING STEEL IN THE DIAMOND LIGHT BACK OVEN AND THE DIAM LIGHT BACK OVEN FOR IMPLEMENTING THE KIT
GB1504443A (en) * 1975-04-25 1978-03-22 Dso Cherna Metalurgia Method of steelmaking with direct current
US4132545A (en) * 1975-12-08 1979-01-02 Rabinovich Volf I Method of electroslag remelting processes using a preheated electrode shield
SE435548B (en) * 1980-03-10 1984-10-01 Asea Ab DISTRIBUTION OF DRAWERS OR DRAWINGS FOR DIRECTLY WITH AT LEAST ONE LIGHT BACK ELECTRODE
DE3406760A1 (en) * 1984-02-24 1985-09-05 C. Conradty Nürnberg GmbH & Co KG, 8505 Röthenbach METHOD AND DEVICE FOR MELTING AND HEATING MATERIALS

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR846004A (en) * 1939-09-07
US1333950A (en) * 1916-03-24 1920-03-16 Ludlum Electric Furnace Corp Electric furnace
US3709997A (en) * 1970-12-20 1973-01-09 J Alferov Convertible electrode electric furnace installation and method
FR2197988A1 (en) * 1972-08-29 1974-03-29 Nipkti Po Cherna Metalurgia
DE2355168A1 (en) * 1972-11-17 1974-05-30 Allmaenna Svenska Elek Ska Ab MELTING PROCESS FOR ARC FURNACE USING DC CURRENT AND ARC FURNACE FOR PERFORMING THE PROCESS
DE3232551A1 (en) * 1981-12-01 1983-06-09 Iso "Metalurgkomplekt", Sofija METHOD AND DEVICE FOR TREATING AND REFINING LIQUID METAL ALLOYS BY MEANS OF DC-ARC HEATING

Also Published As

Publication number Publication date
DK229585A (en) 1985-11-25
US4646318A (en) 1987-02-24
DE3419681C2 (en) 1989-09-28
JPH0123916B2 (en) 1989-05-09
DK229585D0 (en) 1985-05-23
ES295801U (en) 1987-06-16
BR8502426A (en) 1986-01-28
ES295801Y (en) 1987-12-16
DE3419681A1 (en) 1985-11-28
EP0167475B1 (en) 1989-12-27
DK163402B (en) 1992-02-24
JPS60254592A (en) 1985-12-16
DE3575065D1 (en) 1990-02-01
DK163402C (en) 1992-07-13

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