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EP0106767B1 - Device for measuring the arc tension in a furnace - Google Patents

Device for measuring the arc tension in a furnace Download PDF

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Publication number
EP0106767B1
EP0106767B1 EP83402004A EP83402004A EP0106767B1 EP 0106767 B1 EP0106767 B1 EP 0106767B1 EP 83402004 A EP83402004 A EP 83402004A EP 83402004 A EP83402004 A EP 83402004A EP 0106767 B1 EP0106767 B1 EP 0106767B1
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EP
European Patent Office
Prior art keywords
voltage
metallic
wire
measurement
measuring device
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
Application number
EP83402004A
Other languages
German (de)
French (fr)
Other versions
EP0106767A1 (en
Inventor
Pascal Maes
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.)
Clecim SAS
Original Assignee
Clecim SAS
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 Clecim SAS filed Critical Clecim SAS
Priority to AT83402004T priority Critical patent/ATE20800T1/en
Publication of EP0106767A1 publication Critical patent/EP0106767A1/en
Application granted granted Critical
Publication of EP0106767B1 publication Critical patent/EP0106767B1/en
Expired 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
    • 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
    • H05B7/101—Mountings, supports or terminals at head of electrode, i.e. at the end remote from the arc

Definitions

  • the present invention relates to a device for measuring, on each of the electrodes, the arc voltage during operation of an electric furnace intended for melting or transforming scrap.
  • the electric arc furnace is a device which aims to melt a metallic charge, put in the form of loose scrap, to obtain a molten steel bath.
  • This liquid metal may or may not be refined in the arc furnace itself to make it a steel of given characteristics. Above all, and this trend is becoming more and more marked in modern steelworks, the electric arc furnace is a tool for melting scrap.
  • An arc furnace is equipped with three vertical graphite electrodes.
  • the electrodes are each equipped with an individual raising and lowering means which allows, during the melting of a scrap charge, to be at all times at the right distance from the scrap.
  • the arcs are established between each of the electrodes and the charge to be melted.
  • the current which circulates in the electrodes is a three-phase alternating current, normally balanced, or almost, whose value is calculated in tens of thousands of amperes.
  • the current supply circuit has a significant impedance in front of the arc impedance, so that the arc voltage represents only about 70 to 90% of the voltage across the transformer.
  • the impedance of the current supply circuit is above all reactive, and its value is not constant because it depends on the geometry of the circuit, essentially deformable by the fact that the electrodes have possibilities of vertical translation of several meters during the time the arcs are established.
  • the measurement of the arc voltage comes from a calculation starting from a measured voltage value, either at the terminals of the supply transformer, or at the downstream ends of the cables for bringing the current leaving from these terminals.
  • the result of this measurement is very imprecise because the impedance of the circuit is variable and its value cannot be determined when calculating the arc voltage; for this calculation, it is assumed to have a constant mean value, which is necessarily inaccurate.
  • the results are not better, because then the measured voltage is false, due to the strong influence of the power currents which induce voltages error in the measurement circuit.
  • the measuring device of the invention allows a more precise arc voltage measurement than those carried out until now. It is applicable to electric ovens provided with electrodes the upper part of which is metallic and cooled by circulation of water, as described for example in patent US-A-4 121 042, and it is characterized in that it comprises a measuring wire starting from the fixing part of the graphite part of the electrode, passing in the longitudinal axis of the cooled metal part of said electrode, then passing inside one of the supply lines or cooling water return. According to particular characteristics, it results in an electronic assembly for transforming the signal received into light, or other electromagnetic wave, forming part of the measuring member proper, the signal thus transformed then being routed, for example by optical fiber. , towards the control room.
  • the electrode 1 is held by a clamp 6 placed at the end of a support arm 7.
  • the arm 7 is itself carried by a mast 8 adjustable in height by a conventional device not shown.
  • the electrical voltage from one of the three terminals of the secondary of the three-phase supply transformer is applied to the metal clamp 6 using power cables 9 and 10.
  • the metal part 4 of the electrode 1 is cooled by a water circulation circuit comprising a flexible water supply tube 11 terminating in the axis of the electrode, and a flexible water return tube 12 starting from the upper side.
  • an electrical measuring wire 16 starts from the connecting piece 5, or “Nipple”, a circuit along the axis of the cooled metal part 4, then passes inside the supply pipe of water 11, to lead to an electronic box 14 placed at the upstream end of the support arm 7.
  • the electronic box 14 includes a device measuring the instantaneous voltage at point 5, that is to say at the downstream end of the cooled metal part 4, transforming this measured voltage value into an effective voltage value, then converting this measurement into an optical signal which is then transmitted using an optical fiber 15 to the control room. The received signal is then used to regulate the vertical position of the mast 8, that is to say ultimately the arc power.
  • the invention allows a measurement greatly improved arc voltage.
  • the voltage is in fact measured on the connection piece 5, that is to say very close to the end of the electrode 1; the measuring wire 16 passes through the center of the metal part 4 and the induction is zero there because the electromagnetic field is zero at the center of a conductor.
  • the wire 16 then continues on its way inside the conduits 11 for supplying cooling water to the electrode. On this portion of the path, parasitic induction exists but is attenuated by the fact that the measurement cable 16 is carefully shielded by the material of the pipes. The measured voltage is converted into light in the box 14 then, transmitted by optical fiber 15, is no longer disturbed.
  • FIG. 2 shows the detail of the connections of the downstream part of the measurement cable 16 and of the water supply hose 11 with the cooled metal part 4.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Furnace Details (AREA)
  • Discharge Heating (AREA)
  • Force Measurement Appropriate To Specific Purposes (AREA)
  • Radiation Pyrometers (AREA)
  • Investigating Or Analyzing Materials Using Thermal Means (AREA)

Abstract

A system which permits the measurement, during operation, of the arc voltage electrodes having an upper metal portion (4) cooled by circulating water. The system employs an electrical instrumentation-cable (16) attached to a piece (5) for fixing the graphite consumable portion (3) of the electrode. This cable runs along the axis of the metal portion (4) and then inside one of the water-supply pipes (11), terminating at an electronic box (14) which converts the incoming measurement signal into a light wave.

Description

La présente invention se rapporte à un dispositif permettant de mesurer, sur chacune des électrodes, la tension d'arc en cours de fonctionnement d'un four électrique destiné à la fusion ou à la transformation de ferrailles.The present invention relates to a device for measuring, on each of the electrodes, the arc voltage during operation of an electric furnace intended for melting or transforming scrap.

Le four électrique à arc est un appareil qui a pour but de fondre une charge métallique, mise sous forme de ferrailles en vrac, pour obtenir un bain fondu d'acier. Ce métal liquide peut ou non être affiné dans le four à arc lui-même pour en faire un acier de caractéristiques données. Avant tout, et cette tendance se marque de plus en plus dans les aciéries modernes, le four électrique à arc est un outil de fusion de ferrailles.The electric arc furnace is a device which aims to melt a metallic charge, put in the form of loose scrap, to obtain a molten steel bath. This liquid metal may or may not be refined in the arc furnace itself to make it a steel of given characteristics. Above all, and this trend is becoming more and more marked in modern steelworks, the electric arc furnace is a tool for melting scrap.

Un four à arc est équipé de trois électrodes verticales en graphite. Les électrodes sont équipées chacune d'un moyen individuel de montée et descente qui permet, pendant la fusion d'une charge de ferrailles, d'être à tout moment à la bonne distance de la ferraille. Les arcs s'établissent entre chacune des électrodes et la charge à fondre. Le courant qui circule dans les électrodes est un courant alternatif triphasé, normalement équilibré, ou presque, dont la valeur se chiffre en dizaines de milliers d'ampères. Le circuit d'amenée du courant présente une impédance non négligeable devant l'impédance d'arc, ce qui fait que la tension d'arc représente environ 70 à 90% seulement de la tension aux bornes du transformateur. L'impédance du circuit d'amenée du courant est surtout réactive, et sa valeur n'est pas constante car elle dépend de la géométrie du circuit, essentiellement déformable par le fait que les électrodes ont des possibilités de translation verticale de plusieurs mètres pendant le temps que les arcs sont établis.An arc furnace is equipped with three vertical graphite electrodes. The electrodes are each equipped with an individual raising and lowering means which allows, during the melting of a scrap charge, to be at all times at the right distance from the scrap. The arcs are established between each of the electrodes and the charge to be melted. The current which circulates in the electrodes is a three-phase alternating current, normally balanced, or almost, whose value is calculated in tens of thousands of amperes. The current supply circuit has a significant impedance in front of the arc impedance, so that the arc voltage represents only about 70 to 90% of the voltage across the transformer. The impedance of the current supply circuit is above all reactive, and its value is not constant because it depends on the geometry of the circuit, essentially deformable by the fact that the electrodes have possibilities of vertical translation of several meters during the time the arcs are established.

Afin de permettre la régulation souhaitée de l'énergie appliquée à la ferraille dans le four, il est nécessaire de connaître à chaque instant la tension d'arc de chacune des électrodes.In order to allow the desired regulation of the energy applied to the scrap in the furnace, it is necessary to know at all times the arc voltage of each of the electrodes.

Dans la technique actuelle, la mesure de la tension d'arc est issue d'un calcul partant d'une valeur de tension mesurée, soit aux bornes du transformateur d'alimentation, soit aux extrémités aval des câbles d'amenée du courant partant de ces bornes. Le résultat de cette mesure est très imprécis car l'impédance du circuit est variable et sa valeur ne peut être déterminée au moment du calcul de la tension d'arc; elle est, pour ce calcul, supposée avoir une valeur moyenne constante, ce qui est forcément inexact. Dans le cas où l'on mesure la tension à l'extrémité aval des câbles d'alimentation, les résultats ne sont pas meilleurs, car alors la tension mesurée est fausse, en raison de la forte influence des courants de puissance qui induisent des tensions d'erreur dans le circuit de mesure.In the current technique, the measurement of the arc voltage comes from a calculation starting from a measured voltage value, either at the terminals of the supply transformer, or at the downstream ends of the cables for bringing the current leaving from these terminals. The result of this measurement is very imprecise because the impedance of the circuit is variable and its value cannot be determined when calculating the arc voltage; for this calculation, it is assumed to have a constant mean value, which is necessarily inaccurate. In the case where the voltage at the downstream end of the power cables is measured, the results are not better, because then the measured voltage is false, due to the strong influence of the power currents which induce voltages error in the measurement circuit.

Le dispositif de mesure de l'invention permet une mesure de tension d'arc plus précise que celles effectuées jusqu'alors. Il est applicable aux fours électriques munis d'électrodes dont la partie supérieure est métallique et refroidie par circulation d'eau, tel que décrit par exemple dans le brevet US-A-4 121 042, et il est caractérisé en ce qu'il comporte un fil de mesure partant de la pièce de fixation de la partie en graphite de l'électrode, passant dans l'axe longitudinal de la partie métallique refroidie de ladite électrode, puis passant à l'intérieur d'une des conduites d'amenée ou de retour d'eau de refroidissement. D'après des caractéristiques particulières, il aboutit à un ensemble électronique de transformation du signal reçu en lumière, ou autre onde électromagnétique, faisant partie de l'organe de mesure proprement dit, le signal ainsi transformé étant alors acheminé, par exemple par fibre optique, vers la salle de contrôle.The measuring device of the invention allows a more precise arc voltage measurement than those carried out until now. It is applicable to electric ovens provided with electrodes the upper part of which is metallic and cooled by circulation of water, as described for example in patent US-A-4 121 042, and it is characterized in that it comprises a measuring wire starting from the fixing part of the graphite part of the electrode, passing in the longitudinal axis of the cooled metal part of said electrode, then passing inside one of the supply lines or cooling water return. According to particular characteristics, it results in an electronic assembly for transforming the signal received into light, or other electromagnetic wave, forming part of the measuring member proper, the signal thus transformed then being routed, for example by optical fiber. , towards the control room.

L'invention sera mieux comprise à l'aide de la description suivante d'un exemple de réalisation, en référence aux dessins annexés dans lesquels:

  • la figure 1 est une vue d'ensemble schématique du dispositif de mesure de l'invention
  • la figure 2 est une vue en coupe longitudinale d'une électrode refroidie équipée du dispositif de mesure de l'invention.
The invention will be better understood using the following description of an exemplary embodiment, with reference to the accompanying drawings in which:
  • Figure 1 is a schematic overview of the measuring device of the invention
  • Figure 2 is a longitudinal sectional view of a cooled electrode equipped with the measuring device of the invention.

On reconnaît sur la figure 1 une des trois électrodes 1 passant au travers du couvercle 2 d'un four électrique à arcs, composée d'une partie inférieure 3 en graphite consommable et d'une partie supérieure 4 métallique et refroidie par circulation d'eau, les deux parties 3 et 4 étant réunies par une pièce bi-tronconique filetée 5, appelée «Nipple». De telles électrodes sont connues depuis quelques années seulement et sont décrites dans quelques publications récentes, tel que par exemple le brevet US-A-4 121 042.We recognize in Figure 1 one of the three electrodes 1 passing through the cover 2 of an electric arc furnace, consisting of a lower part 3 in consumable graphite and an upper part 4 metallic and cooled by water circulation , the two parts 3 and 4 being joined by a bi-frustoconical threaded part 5, called "Nipple". Such electrodes have only been known for a few years and have been described in some recent publications, such as, for example, US Pat. No. 4,121,042.

L'électrode 1 est tenue par une pince 6 placée en bout d'un bras de support 7. Le bras 7 est lui-même porté par un mât 8 réglable en hauteur par un dispositif classique non représenté.The electrode 1 is held by a clamp 6 placed at the end of a support arm 7. The arm 7 is itself carried by a mast 8 adjustable in height by a conventional device not shown.

La tension électrique issue d'une des trois bornes du secondaire du transformateur triphasé d'alimentation est appliquée sur la pince métallique 6 à l'aide de câbles de puissance 9 et 10.The electrical voltage from one of the three terminals of the secondary of the three-phase supply transformer is applied to the metal clamp 6 using power cables 9 and 10.

La partie métallique 4 de l'électrode 1 est refroidie par un circuit de circulation d'eau comportant un tube flexible d'amenée d'eau 11 aboutissant dans l'axe de l'électrode, et un tube flexible de retour d'eau 12 en partant par le côté supérieur.The metal part 4 of the electrode 1 is cooled by a water circulation circuit comprising a flexible water supply tube 11 terminating in the axis of the electrode, and a flexible water return tube 12 starting from the upper side.

En se reportant également à la figure 2, on peut voir en détails le circuit de circulation d'eau à l'intérieur de la partie métallique refroidie 4 de l'électrode 1. On remarquera que l'eau y circule tout d'abord de haut en bas dans un canal axial 13 parcourant toute la longueur de la partie métallique refroidie 4.Referring also to FIG. 2, one can see in detail the water circulation circuit inside the cooled metal part 4 of the electrode 1. It will be noted that the water circulates there first of all. top to bottom in an axial channel 13 running the entire length of the cooled metal part 4.

Conformément à l'invention, un fil électrique de mesure 16 part de la pièce de raccordement 5, ou «Nipple», circuit selon l'axe de la partie métallique refroidie 4, passe ensuite à l'intérieur du tuyau d'amenée d'eau 11, pour aboutir à un coffret électronique 14 placé à l'extrémité amont du bras de support 7.According to the invention, an electrical measuring wire 16 starts from the connecting piece 5, or “Nipple”, a circuit along the axis of the cooled metal part 4, then passes inside the supply pipe of water 11, to lead to an electronic box 14 placed at the upstream end of the support arm 7.

Le coffret électronique 14 comporte un dispositif mesurant la tension instantanée au point 5, c'est-à-dire à l'extrémité aval de la partie métallique refroidie 4, transformant cette valeur de tension mesurée en valeur de tension efficace, puis convertissant cette mesure en un signal optique qui est alors transmis à l'aide d'une fibre optique 15 vers la salle de commande. Le signal reçu est alors utilisé pour réguler la position verticale du mât 8, c'est-à-dire finalement la puissance d'arc.The electronic box 14 includes a device measuring the instantaneous voltage at point 5, that is to say at the downstream end of the cooled metal part 4, transforming this measured voltage value into an effective voltage value, then converting this measurement into an optical signal which is then transmitted using an optical fiber 15 to the control room. The received signal is then used to regulate the vertical position of the mast 8, that is to say ultimately the arc power.

On remarquera que l'invention permet une mesure de la tension d'arc grandement améliorée. La tension est en effet mesurée sur la pièce de raccordement 5 c'est-à-dire très près de l'extrémité de l'électrode 1; le fil de mesure 16 passe au centre de la partie métallique 4 et l'induction y est nulle car le champ électromagnétique est nul au centre d'un conducteur.It will be noted that the invention allows a measurement greatly improved arc voltage. The voltage is in fact measured on the connection piece 5, that is to say very close to the end of the electrode 1; the measuring wire 16 passes through the center of the metal part 4 and the induction is zero there because the electromagnetic field is zero at the center of a conductor.

Le fil 16 continue ensuite son chemin à l'intérieur des conduites 11 d'amenée d'eau de refroidissement de l'électrode. Sur cette portion de chemin, l'induction parasite existe mais est atténuée par le fait que le câble de mesure 16 est soigneusement blindé par le matériau des tuyauteries. La tension mesurée est convertie en lumière dans le coffret 14 puis, transmise par fibre optique 15, ne subit plus de pertuba- tions.The wire 16 then continues on its way inside the conduits 11 for supplying cooling water to the electrode. On this portion of the path, parasitic induction exists but is attenuated by the fact that the measurement cable 16 is carefully shielded by the material of the pipes. The measured voltage is converted into light in the box 14 then, transmitted by optical fiber 15, is no longer disturbed.

La figure 2 montre le détail des connexions de la partie aval du câble de mesure 16 et du flexible d'amenée d'eau 11 avec la partie métallique refroidie 4.FIG. 2 shows the detail of the connections of the downstream part of the measurement cable 16 and of the water supply hose 11 with the cooled metal part 4.

Dans le conduit central 13 par lequel arrive l'eau de refroidissement amenée par le flexible 11 et circulant comme indiqué par les flèches, on trouve un tube coaxial 17 fixé à sa partie supérieure par une bride 18 percée de trous pour permettre la circulation d'eau, et centré dans le conduit 13 par des ailettes 19. Dans l'axe de ce tube 17 on trouve le fil conducteur isolé 16 solidaire à son extrémité aval d'une pastille métallique 20 fortement appliquée contre la partie métallique 4 de l'électrode par un bouchon fileté 21. Une prise étanche 22 permet de connecter et de déconnecter rapidement le fil de mesure 16.In the central conduit 13 through which the cooling water supplied by the hose 11 and circulating as indicated by the arrows, there is a coaxial tube 17 fixed to its upper part by a flange 18 pierced with holes to allow the circulation of water, and centered in the conduit 13 by fins 19. In the axis of this tube 17 there is the insulated conductor wire 16 secured at its downstream end with a metal pad 20 strongly applied against the metal part 4 of the electrode by a threaded plug 21. A waterproof socket 22 makes it possible to quickly connect and disconnect the measuring wire 16.

Claims (5)

1. Device for the measurement of the arc voltage on a graphite electrode including a consumable lower part (3) connected by a connecting piece (5) to a metallic upper part (4) cooled by an internal water circulation circuit and to which the voltage is applied, the actual measuring element being connected to the electrode by an electrical measurement wire (16), characterized in that the electrical measurement wire (16) departs from the connecting piece (5) of the lower part (3) and extends along the longitudinal axis of the metallic upper part (4) and then within one of the supply (11) or return (12) conduits of the internal water circulation circuit.
2. Measuring device according to Claim 1, characterized in that the electrical measurement wire (16) leads to an electronic assembly (14) for converting the voltage measurement signal received into an eletromagnetic wave, forming part of the measuring element, the measurement signal thus converted then being transmitted to a control room.
3. Measuring device according to Claim 2, characterized in that the electronic assembly (14) converts the voltage measurement signal into a light wave and is connected by optical fibre to the control room.
4. Measuring device according to Claim 1, characterized in that the water circulation circuit includes a water supply channel (13) extending in the axis of the metallic part (4) over the entire length of the latter, and in which there is placed a coaxial tube (17) within which the electrical wire (16) passes.
5. Measuring device according to Claim 1, characterized in that the electrical wire (16) forms a single unit, at its downstream end, with a metallic plug (20) applied tightly against the metallic part (4) of the electrode by a threaded cap (21).
EP83402004A 1982-10-15 1983-10-14 Device for measuring the arc tension in a furnace Expired EP0106767B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83402004T ATE20800T1 (en) 1982-10-15 1983-10-14 DEVICE FOR MEASURING THE ARC VOLTAGE IN AN ELECTRIC FURNACE.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8217253A FR2534691A1 (en) 1982-10-15 1982-10-15 DEVICE FOR MEASURING ARC VOLTAGE ON AN ELECTRIC FURNACE
FR8217253 1982-10-15

Publications (2)

Publication Number Publication Date
EP0106767A1 EP0106767A1 (en) 1984-04-25
EP0106767B1 true EP0106767B1 (en) 1986-07-16

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Family Applications (1)

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EP83402004A Expired EP0106767B1 (en) 1982-10-15 1983-10-14 Device for measuring the arc tension in a furnace

Country Status (7)

Country Link
US (1) US4559630A (en)
EP (1) EP0106767B1 (en)
JP (1) JPS5991696A (en)
AT (1) ATE20800T1 (en)
DE (1) DE3364532D1 (en)
ES (1) ES526467A0 (en)
FR (1) FR2534691A1 (en)

Families Citing this family (8)

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Publication number Priority date Publication date Assignee Title
DE3319389C2 (en) * 1983-05-26 1987-03-05 Mannesmann AG, 4000 Düsseldorf Electrode for arc furnaces
US4977576A (en) * 1988-09-22 1990-12-11 Great Lakes Carbon Corporation Safety flow stopper for water-cooled electrode
US5324803A (en) * 1991-10-14 1994-06-28 Nof Corporation Polymer comprising fluoroalkl group, a method of preparation thereof, a surface active agent, a surface treatment agent and a coating composition
IT1288858B1 (en) * 1996-02-29 1998-09-25 Danieli Off Mecc ADAPTER DEVICE FOR ELECTRODES, WITH AUXILIARY REACTANCE FUNCTION, IN AN ELECTRIC ARC OVEN.
IT1288992B1 (en) * 1996-09-27 1998-09-25 Danieli Off Mecc COOLING SYSTEM FOR CATHODES FOR DIRECT ARC ELECTRIC OVENS
BRPI0613414A8 (en) * 2005-07-22 2016-10-18 Siemens Ag METHOD FOR DETERMINING AT LEAST ONE VARIABLE STATE OF AN ELECTRIC ARC OVEN, AND ELECTRIC ARC OVEN
IT1396173B1 (en) * 2009-03-25 2012-11-16 Tenova Spa MEASUREMENT EQUIPMENT OF THE POSITION OF THE ELECTRODES IN AN ELECTRIC OVEN
DE102010025236A1 (en) * 2010-02-18 2011-08-18 SMS Siemag AG, 40237 Electrode support arm of a smelting metallurgical furnace

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Publication number Priority date Publication date Assignee Title
US4121042A (en) * 1976-09-01 1978-10-17 The Steel Company Of Canada Limited Composite electrode with non-consumable upper section

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Publication number Priority date Publication date Assignee Title
DE1048649B (en) * 1957-08-24 1959-01-15 W C Heraeus Device for measuring the arc length in arc melting systems
US3610601A (en) * 1969-10-01 1971-10-05 Allegheny Ludlum Steel Apparatus for positioning a consumable lance
US3978311A (en) * 1974-03-26 1976-08-31 Union Carbide Corporation Voltage sensor circuit for an arc welding wire feed control
US4168392A (en) * 1976-09-01 1979-09-18 The Steel Company Of Canada, Limited Composite electrode with non-consumable upper section
DE2725537A1 (en) * 1977-06-06 1978-12-14 Korf Stahl ELECTRODE FOR ARC FURNACE

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4121042A (en) * 1976-09-01 1978-10-17 The Steel Company Of Canada Limited Composite electrode with non-consumable upper section

Also Published As

Publication number Publication date
FR2534691A1 (en) 1984-04-20
ES8405957A1 (en) 1984-06-16
ES526467A0 (en) 1984-06-16
DE3364532D1 (en) 1986-08-21
EP0106767A1 (en) 1984-04-25
FR2534691B1 (en) 1984-12-28
US4559630A (en) 1985-12-17
ATE20800T1 (en) 1986-08-15
JPS5991696A (en) 1984-05-26

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