EP0201801A2 - Contact jaw for an electrode holder - Google Patents

Contact jaw for an electrode holder Download PDF

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Publication number
EP0201801A2
EP0201801A2 EP86105909A EP86105909A EP0201801A2 EP 0201801 A2 EP0201801 A2 EP 0201801A2 EP 86105909 A EP86105909 A EP 86105909A EP 86105909 A EP86105909 A EP 86105909A EP 0201801 A2 EP0201801 A2 EP 0201801A2
Authority
EP
European Patent Office
Prior art keywords
contact jaw
contact
coating
insulating material
electrode holder
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Withdrawn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
EP86105909A
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German (de)
French (fr)
Other versions
EP0201801A3 (en
Inventor
Hans Friedrich
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.)
Fried Krupp AG
Original Assignee
Fried Krupp AG
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Filing date
Publication date
Application filed by Fried Krupp AG filed Critical Fried Krupp AG
Publication of EP0201801A2 publication Critical patent/EP0201801A2/en
Publication of EP0201801A3 publication Critical patent/EP0201801A3/en
Withdrawn legal-status Critical Current

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    • 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
    • H05B7/10—Mountings, supports, terminals or arrangements for feeding or guiding electrodes
    • H05B7/103—Mountings, supports or terminals with jaws

Definitions

  • the invention relates to a copper contact jaw which is insulated from and releasable to the electrode socket of an electric furnace for the current transmission from the supply lines to the electrodes.
  • Such contact jaws have so far been cast or welded in one or more parts and, if appropriate, have been made with a reinforcement made of stainless steel. Since the insulation layer arranged between the contact jaw and the electrode holder, which is intended to prevent the formation of secondary currents, has often led to damage, which necessitated frequent replacement of the insulating layer, it has already become known to remedy the disadvantage that the surfaces of the electrode holder lying opposite the contact jaw to be coated with an aluminum oxide coating. With this coating, however, the layer thickness has proven to be insufficient, so that neither a sufficient insulating effect nor a satisfactory service life of the insulating layer is achieved.
  • the invention has for its object to counter this disadvantage and to create a contact jaw of the type mentioned, which withstands high and highest loads.
  • the invention consists in the features of the characterizing part of claim 1.
  • the contact jaw according to the invention has the advantage that the layer thickness of the insulating layer could be increased considerably.
  • Advantageous embodiments of the invention are given in claims 2 to 5.
  • the coating is produced by an injection molding process.
  • a chromium-zirconium alloyed and tempered hard copper in which the zirconium content is between 0.003 and 0.5% and the chromium content between 0.3 and 1.2, gives good results with regard to a particularly large thickness of the insulating layer % lies. These contents depend in particular on the homogeneity of the copper melt, i.e. if the homogeneity is high, the lower limit values can suffice.
  • the mechanical properties of the hard copper are significantly improved by heat treating the material before applying the insulating layer.
  • the contact jaw consists of a bar 1, which is shaped in the shape of a cylinder jacket to adapt to the surface of the indicated electrode 2 and is provided at its upper end with a lug (3) for connection to the current supply lines.
  • the bar 1 is provided in the region of its upper end with a bracket 5 which is supported against the top of the electrode holder 4 and by means of two locking screws 6 which reach through holes 7 in the bracket 5 , is attached.
  • a stiffening web 8 is welded in between the flag 3 and the bracket 5.
  • the ingot 1 has, as can be seen from FIGS. 2 and 3, a vertically extending recess 9 on its side facing the electrode 2, so that there is a symmetrical contact surface 10 on both sides.
  • the ingot 1 also has lines 11 for water cooling.
  • the electrode holder 4 has an upper and a lower contact surface 12 or 13 facing the electrode 2, each of which is opposite a coating 14 made of insulating material, which is sprayed onto the bars 1 at this point.
  • the underside of the console 5 also has an equally thick coating 15 made of the same insulating material. The coating 15 is drawn around the lower edges of the console 5 for better insulation and merges into the coating 15 at the corner between the ingot 1 and the console 5. Between the coatings 14 and 15 on the one hand and the bar 1 or the console 5 on the other is one metallic adhesive layer made of a nickel-aluminum alloy.
  • the support surfaces 12 and 13 of the electrode holder 4 each encompass the bar 1 by a certain amount, as can be seen from FIG. 2.
  • a lateral guide 16, which is incorporated into the electrode holder 4, is incorporated in each case at the points of the lateral gripping to prevent transverse movements of the ingot 1 under load.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Arc Welding In General (AREA)
  • Coating By Spraying Or Casting (AREA)
  • Contacts (AREA)
  • Surgical Instruments (AREA)
  • Liquid Crystal (AREA)
  • Spinning Or Twisting Of Yarns (AREA)
  • Measurement Of Radiation (AREA)

Abstract

Bei einer gegenüber der Elektrodenfassung (2) eines Elektroofens isolierte und lösbar an dieser befestigten Kontaktbacke aus Kupfer für die Stromübertragung von den Zuführleitungen auf die Elektroden (2) wird eine lange Standzeit und sichere Isolierung dadurch erzielt, daß die Kontaktbacke zumindest an den der Elektrodenfassung (4) zugewandten Anlageflächen (12, 13) mit einem Überzug aus einem keramischen Isolierstoff versehen ist und zwischen dem Isolierstoff und der aus Hartkupfer bestehenden Kontaktbacke eine metallische Haftschicht angeordnet ist.In the case of a copper contact jaw insulated from the electrode socket (2) of an electric furnace and detachably attached to it for the current transmission from the supply lines to the electrodes (2), a long service life and reliable insulation are achieved in that the contact jaw at least on the electrode socket ( 4) facing contact surfaces (12, 13) is provided with a coating of a ceramic insulating material and a metallic adhesive layer is arranged between the insulating material and the contact jaw made of hard copper.

Description

Kontaktbacke einer ElektrodenfassungContact jaw of an electrode holder

Die Erfindung bezieht sich auf eine gegenüber der Elektrodenfasssung eines Elektroofens isolierte und lösbare an dieser befestigte Kontaktbacke aus Kupfer für die Stromübertragung von den Zuführleitungen auf die Elektroden.The invention relates to a copper contact jaw which is insulated from and releasable to the electrode socket of an electric furnace for the current transmission from the supply lines to the electrodes.

Derartige Kontakbacken sind bisher ein- oder mehrteilig gegossen oder geschweißt und ggf. mit einer Verstärkung aus nichtrostendem Stahl ausgeführt worden. Da die zwischen der Kontaktbacke und der Elektrodenfassung angeordnete Isolationsschicht, welche die Bildung von Sekundärströmen verhindern soll, häufig zu Schäden geführt hat, wodurch ein häufiger Austausch der Isolierschicht erforderlich wurde, ist es zur Abhilfe des Nachteils bereits bekanntgeworden, die der Kontaktbacke gegenüberliegenden Flächen der Elektrodenfassung mit einer Beschichtung aus Aluminiumoxid zu versehen. Bei dieser Beschichtung hat sich jedoch die Schichtdicke als nicht ausreichend erwiesen, so daß weder eine hinreichende Isolierwirkung noch eine befriedigende Standzeit der Isolierschicht erreicht wird.Such contact jaws have so far been cast or welded in one or more parts and, if appropriate, have been made with a reinforcement made of stainless steel. Since the insulation layer arranged between the contact jaw and the electrode holder, which is intended to prevent the formation of secondary currents, has often led to damage, which necessitated frequent replacement of the insulating layer, it has already become known to remedy the disadvantage that the surfaces of the electrode holder lying opposite the contact jaw to be coated with an aluminum oxide coating. With this coating, however, the layer thickness has proven to be insufficient, so that neither a sufficient insulating effect nor a satisfactory service life of the insulating layer is achieved.

Der Erfindung liegt die Aufgabe zugrunde, diesem Nachteil zu begegnen und eine Kontaktbacke der eingangs genannten Art zu schaffen, welche hohen und höchsten Belastungen standhält. Die Erfindung besteht in den Merkmalen des kennzeichnenden Teils des Anspruchs 1.The invention has for its object to counter this disadvantage and to create a contact jaw of the type mentioned, which withstands high and highest loads. The invention consists in the features of the characterizing part of claim 1.

Gegenüber den bekannten Kontaktbacken hat die Kontaktbacke nach der Erfindung den Vorteil, daß die Schichtdicke der Isolierschicht erheblich verstärkt werden konnte. Vorteilhafte Ausgestaltungen der Erfindung sind in den Ansprüchen 2 bis 5 wiedergegeben.Compared to the known contact jaws, the contact jaw according to the invention has the advantage that the layer thickness of the insulating layer could be increased considerably. Advantageous embodiments of the invention are given in claims 2 to 5.

Besonders vorteilhafte Ergebnisse werden erzielt, wenn als metallische Haftschicht eine Nickel-Aluminium-Legierung verwendet wird, deren Dehnbarkeit eine gute Haftwirkung zur Folge hat.Particularly advantageous results are achieved if a nickel-aluminum alloy is used as the metallic adhesive layer, the ductility of which results in a good adhesive effect.

Besonders vorteilhaft ist es, wenn der Überzug durch ein Aufspritzverfahren hergestellt wird. Gute Ergebnisse im Hinblick auf eine besonders große Stärke der Isolierschicht ergibt die Verwendung eines chrom-zirkon-legierten und vergüteten Hartkupfers, bei dem der Zirkon-Gehalt zwischen 0,003 und 0,5 % und der Chrom-Gehalt zwischen 0,3 und 1,2 % liegt. Diese Gehalte hängen insbesondere auch von der Homogenität der Kupferschmelze ab, d.h. bei großer Homogenität können die unteren Grenzwerte ausreichen. Durch eine das Material vergütende Wärmebehandlung vor dem Aufbringen der Isolierschicht werden die mechanischen Werte des Hartkupfers noch erheblich verbessert.It is particularly advantageous if the coating is produced by an injection molding process. The use of a chromium-zirconium alloyed and tempered hard copper, in which the zirconium content is between 0.003 and 0.5% and the chromium content between 0.3 and 1.2, gives good results with regard to a particularly large thickness of the insulating layer % lies. These contents depend in particular on the homogeneity of the copper melt, i.e. if the homogeneity is high, the lower limit values can suffice. The mechanical properties of the hard copper are significantly improved by heat treating the material before applying the insulating layer.

In der Zeichnung ist ein Ausführungsbeispiel einer Kontaktbacke nach der Erfindung schematisch dargestellt und im folgenden näher erläutert.In the drawing, an embodiment of a contact jaw according to the invention is shown schematically and explained in more detail below.

Es zeigen:

  • Fig. 1 eine Kontaktbacke nach der Erfindung im lotrechten Mittelschnitt mit angedeuteten Anschlußteilen,
  • Fig. 2 einen Schnitt nach der Linie II-II in Fig. 1 und
  • Fig. 3 einen Schnitt nach der Linie III-III in Fig. 1.
Show it:
  • 1 is a contact jaw according to the invention in a vertical central section with indicated connecting parts,
  • Fig. 2 shows a section along the line II-II in Fig. 1 and
  • 3 shows a section along the line III-III in FIG. 1st

Wie Fig. 1 zeigt, besteht die Kontaktbacke aus einem Barren 1, welcher zur Anpassung an die Oberfläche der angedeuteten Elektrode 2 zylindermantelförmig geformt ist und an seinem oberen Ende mit einer Fahne (3) zum Anschluß an die stromzuführenden Stromleitungen versehen ist. Zur Befestigung an eine radial an die Elektrode 2 herangeführten Elektrodenfassung 4 ist der Barren 1 im Bereich seines oberen Endes mit einer Konsole 5 versehen, welche sich gegen die Oberseite der Elektrodenfassung 4 abstützt und mittels zwei Absteckschrauben 6, welche durch Bohrungen 7 der Konsolen 5 hindurchgreifen, befestigt ist . Zwischen der Fahne 3 und der Konsole 5 ist ein Versteifungssteg 8 eingeschweißt.As shown in FIG. 1, the contact jaw consists of a bar 1, which is shaped in the shape of a cylinder jacket to adapt to the surface of the indicated electrode 2 and is provided at its upper end with a lug (3) for connection to the current supply lines. For attachment to an electrode holder 4 radially brought up to the electrode 2, the bar 1 is provided in the region of its upper end with a bracket 5 which is supported against the top of the electrode holder 4 and by means of two locking screws 6 which reach through holes 7 in the bracket 5 , is attached. A stiffening web 8 is welded in between the flag 3 and the bracket 5.

Der Barren 1 weist, wie es aus den Fig. 2 und 3 erkennbar ist, an seiner der Elektrode 2 zugewandten Seite eine sich senkrecht erstreckende Ausnehmung 9 auf, so daß sich beidseitig jeweils eine symmetrische Kontaktfläche 10 ergibt. Der Barren 1 weist ferner Leitungen 11 für eine Wasserkühlung auf. Die Elektrodenfassung 4 weist eine oberen und eine untere der Elektrode 2 zugewandte Anlagefläche 12 bzw. 13 auf, welche jeweils ein Überzug 14 aus Isolierstoff, der auf den Barren 1 an dieser Stelle aufgespritzt ist, gegenüberliegt. Einen gleichstarken Überzug 15 aus dem gleichen Isolierstoff weist ferner die Unterseite der Konsole 5 auf. Der Überzug 15 ist zur besseren Isolierwirkung um die unteren Kanten der Konsole 5 herumgezogen und geht in den Überzug 15 an der Ecke zwischen dem Barren 1 und der Konsole 5 über. Zwischen den Überzügen 14 und 15 einerseits und dem Barren 1 bzw. der Konsole 5 andererseits ist jeweils eine metallische Haftschicht aus einer Nickel-Aluminium-Legierung angeordnet.The ingot 1 has, as can be seen from FIGS. 2 and 3, a vertically extending recess 9 on its side facing the electrode 2, so that there is a symmetrical contact surface 10 on both sides. The ingot 1 also has lines 11 for water cooling. The electrode holder 4 has an upper and a lower contact surface 12 or 13 facing the electrode 2, each of which is opposite a coating 14 made of insulating material, which is sprayed onto the bars 1 at this point. The underside of the console 5 also has an equally thick coating 15 made of the same insulating material. The coating 15 is drawn around the lower edges of the console 5 for better insulation and merges into the coating 15 at the corner between the ingot 1 and the console 5. Between the coatings 14 and 15 on the one hand and the bar 1 or the console 5 on the other is one metallic adhesive layer made of a nickel-aluminum alloy.

Die Stützflächen 12 und 13 der Elektrodenfassung 4 umgreifen den Barren 1 jeweils um einen gewissen Betrag, wie es aus Fig. 2 ersichtlich ist. An den Stellen der seitlichen Umgreifung ist jeweils eine in die Elektrodenfassung 4 eingearbeitete seitliche Führung 16 eingearbeitet, um Querbewegungen des Barrens 1 unter Belastung zu verhindern.The support surfaces 12 and 13 of the electrode holder 4 each encompass the bar 1 by a certain amount, as can be seen from FIG. 2. A lateral guide 16, which is incorporated into the electrode holder 4, is incorporated in each case at the points of the lateral gripping to prevent transverse movements of the ingot 1 under load.

Claims (5)

1. Gegenüber der Elektrodenfassung eines Elektrolichtbogenofens isolierte und lösbar an dieser befestigte Kontaktbacke aus Kupfer für die Stromübertragung von den Zuführleitungen auf die Elektroden, dadurch gekennzeichnet, daß sie zumindest an den der Elektrodenfassung zugewandten Anlageflächen mit einem Überzug aus einem keramischen Isolierstoff versehen ist und zwischen dem Isolierstoff und der aus Hartkupfer bestehenden Kontaktbacke eine metallische Haftschicht angeordnet ist.1. Compared to the electrode holder of an electric arc furnace and detachably attached to this contact jaw made of copper for the power transmission from the supply lines to the electrodes, characterized in that it is provided at least on the contact surfaces facing the electrode holder with a coating of a ceramic insulating material and between the Insulating material and the contact jaw consisting of hard copper, a metallic adhesive layer is arranged. 2. Kontaktbacke nach Anspruch 1, dadurch gekennzeichnet, daß der Isolierstoff aus keramischem Material, reines Aluminiumoxid und die metallische Haftschicht eine Nickel-Aluminium-Legierung ist.2. Contact jaw according to claim 1, characterized in that the insulating material made of ceramic material, pure aluminum oxide and the metallic adhesive layer is a nickel-aluminum alloy. 3. Kontaktbacke nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß der Überzug durch ein Aufspritzverfahren hergestellt ist.3. Contact jaw according to claim 1 or 2, characterized in that the coating is made by an injection molding process. 4. Kontaktbacke nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß sich die Kontaktbacken-bezogen auf ihren horizontalen Querschnitt - an paarweise an den Elektrodenfassungen angeordneten Führungen seitlich mit ihrem Überzug abstützen.4. Contact jaw according to one of the preceding claims, characterized in that the contact jaws — based on their horizontal cross section — are laterally supported on guides arranged in pairs on the electrode holders with their coating. 5. Kontaktbacke nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Kontaktbacke aus einem chrom-zirkon-legierten, vergüteten Hartkupfer besteht.5. Contact jaw according to one of the preceding claims, characterized in that the contact jaw consists of a chrome-zirconium alloyed, tempered hard copper.
EP86105909A 1985-05-11 1986-04-29 Contact jaw for an electrode holder Withdrawn EP0201801A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853517069 DE3517069A1 (en) 1985-05-11 1985-05-11 CONTACT JACK OF AN ELECTRODE SOCKET
DE3517069 1985-05-11

Publications (2)

Publication Number Publication Date
EP0201801A2 true EP0201801A2 (en) 1986-11-20
EP0201801A3 EP0201801A3 (en) 1988-01-20

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ID=6270520

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86105909A Withdrawn EP0201801A3 (en) 1985-05-11 1986-04-29 Contact jaw for an electrode holder

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US (1) US4700356A (en)
EP (1) EP0201801A3 (en)
DE (1) DE3517069A1 (en)
NO (1) NO861734L (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4122151A1 (en) * 1991-07-04 1993-01-07 Flohe Gmbh & Co ELECTRODE SOCKET OF AN ELECTRODE ARM
DE102004005051A1 (en) * 2004-01-30 2005-08-18 Arndt Dung At the free end of a component of an electric furnace forming Elektrodentragarms interchangeable arranged contact jaw
KR100648614B1 (en) 2005-12-09 2006-11-23 주식회사 포스코 Electrode rod clamping apparatus with electrode rod cut prevention function
CN102781132A (en) * 2012-07-29 2012-11-14 江苏德诚冶金电炉设备有限公司 Double ejecting block copper tile for ore smelting furnace

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2258052A1 (en) * 1972-03-22 1973-09-27 Bbc Brown Boveri & Cie CLAMPING JAWS FOR RELEASABLE HIGH CURRENT CONNECTIONS, ESPECIALLY IN ELECTRIC WASHER REMOVAL SYSTEMS OR ELECTRIC OVENS
FR2466168A1 (en) * 1979-09-24 1981-03-27 Roche Maurice Electric current connector - esp. for supplying current via contact segments to electrode in metallurgical furnace
DE3409180A1 (en) * 1983-03-15 1984-09-20 NPP po Elektrotermia, Sofia CONTACT HEAD FOR ELECTRODE HOLDER OF ARC FURNACE

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4323717A (en) * 1979-02-07 1982-04-06 British Steel Corporation Furnace electrode clamps
US4417097A (en) * 1981-06-04 1983-11-22 Aluminum Company Of America High temperature, corrosion resistant coating and lead for electrical current

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2258052A1 (en) * 1972-03-22 1973-09-27 Bbc Brown Boveri & Cie CLAMPING JAWS FOR RELEASABLE HIGH CURRENT CONNECTIONS, ESPECIALLY IN ELECTRIC WASHER REMOVAL SYSTEMS OR ELECTRIC OVENS
FR2466168A1 (en) * 1979-09-24 1981-03-27 Roche Maurice Electric current connector - esp. for supplying current via contact segments to electrode in metallurgical furnace
DE3409180A1 (en) * 1983-03-15 1984-09-20 NPP po Elektrotermia, Sofia CONTACT HEAD FOR ELECTRODE HOLDER OF ARC FURNACE

Also Published As

Publication number Publication date
DE3517069A1 (en) 1986-11-13
EP0201801A3 (en) 1988-01-20
NO861734L (en) 1986-11-12
US4700356A (en) 1987-10-13

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