EP0410875B1 - Electrode for plasma arc torch, and torch using such an electrode - Google Patents

Electrode for plasma arc torch, and torch using such an electrode Download PDF

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Publication number
EP0410875B1
EP0410875B1 EP90402132A EP90402132A EP0410875B1 EP 0410875 B1 EP0410875 B1 EP 0410875B1 EP 90402132 A EP90402132 A EP 90402132A EP 90402132 A EP90402132 A EP 90402132A EP 0410875 B1 EP0410875 B1 EP 0410875B1
Authority
EP
European Patent Office
Prior art keywords
electrode
torch
insert
face
nozzle
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
Application number
EP90402132A
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German (de)
French (fr)
Other versions
EP0410875A1 (en
Inventor
Patrick Degrigny
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.)
Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Lincoln Electric Co France SA
Original Assignee
La Soudure Autogene Francaise
Air Liquide SA
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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 La Soudure Autogene Francaise, Air Liquide SA, LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude filed Critical La Soudure Autogene Francaise
Priority to AT90402132T priority Critical patent/ATE102431T1/en
Publication of EP0410875A1 publication Critical patent/EP0410875A1/en
Application granted granted Critical
Publication of EP0410875B1 publication Critical patent/EP0410875B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00—Generating plasma; Handling plasma
    • H05H1/24—Generating plasma
    • H05H1/26—Plasma torches
    • H05H1/32—Plasma torches using an arc
    • H05H1/34—Details, e.g. electrodes, nozzles
    • H05H1/3442—Cathodes with inserted tip
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00—Generating plasma; Handling plasma
    • H05H1/24—Generating plasma
    • H05H1/26—Plasma torches
    • H05H1/32—Plasma torches using an arc
    • H05H1/34—Details, e.g. electrodes, nozzles
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00—Generating plasma; Handling plasma
    • H05H1/24—Generating plasma
    • H05H1/26—Plasma torches
    • H05H1/32—Plasma torches using an arc
    • H05H1/34—Details, e.g. electrodes, nozzles
    • H05H1/3489—Means for contact starting

Definitions

  • the present invention relates to plasma arc work torches with short-circuit ignition. It relates firstly to an electrode for such a torch, of the type comprising an electroconductive support having an end provided with an emissive insert, in particular made of zirconium or hafnium.
  • Plasma cutting torches operating under oxidizing plasma gas are generally equipped with an emissive cathode of zirconium or hafnium, inserted in a copper part acting as an electroconductive support and cooler, the assembly being commonly called electrode.
  • the root of the arc clings to the center of the cathode, where a crater gradually forms on the surface of which a layer of zirconium oxide or hafnium develops.
  • this oxide is fluid and conductive and allows cathodic emission.
  • the oxide solidifies and becomes insulating. Upon solidification, an oxide bead frequently forms on the periphery of the crater, which protrudes from the front surface of the insert.
  • the insert is flush with the end face of the support.
  • the oxide bead protrudes beyond this end face. If this bead has no annoying character in the case of a conventional torch, where the electrode and nozzle are fixed and where the establishment of the arc is initiated by a high frequency discharge, in the case of torches with short-ignition circuit, as described in documents FR-A-2 556 549 and 2 562 748, where the ignition of the arc is obtained by producing a short circuit between the electrode and the nozzle, it sometimes happens that this bead d
  • the oxide forms an electrically insulating barrier which prevents the reliable passage of current between the electrode and the nozzle and, consequently, the reliable ignition of the arc.
  • the object of the invention is to improve the reliability of the ignition of the arc in short-circuit ignition torches, with a simple arrangement and not incurring the costs of manufacturing the torches.
  • it relates to an electrode for a plasma arc work torch, of the aforementioned type, characterized in that a part of the end of the support situated around the insert comprises at least one portion of material electroconductive protruding axially with respect to the insert.
  • the invention also relates to a plasma arc work torch, of the type comprising a torch body in which an electrode having an end face in which an emissive insert is mounted, and a nozzle having an internal face in look of the end face, are mounted movable relative to each other between a first working position, where said faces are spaced from each other and a second position where said faces are in mutual contact , characterized in that, in the second position, a space is provided between the insert and the portion facing the internal face of the nozzle.
  • the torch shown in Figure 1 to the extent necessary for understanding the invention is essentially that described in the document FR-A-2 556 549 cited above. It has a general symmetry of axis XX supposed to be vertical and comprises a tubular body 1 in which is fixed an axial electrode 2.
  • a nozzle holder 3, screwed onto the body 1, defines an abutment shoulder 4 for a shaped nozzle 5 cup mounted sliding axially and biased towards the shoulder 4 by a spring 6 and, in service, also by the pressure of the plasma gas arriving through the annular space 7 existing between the body 1 and the electrode 2.
  • the nozzle 5 which is pierced with a central axial hole 8 for the exit of the arc and the plasma, is axially movable between a normal working position, as shown, spaced from the lower end of the electrode , and a second arc ignition position by short circuit, in which the internal transverse face of the nozzle comes into contact with the lower end face 9 of the electrode by pressing on the metal part to be cut (not shown), an electric voltage being applied between the electrode and this part.
  • the electrode 2 essentially comprises a copper electroconductive support 10, the end face 9 of which is flat and horizontal.
  • a cylindrical counterbore 11 is machined in the end face, and in the flat and horizontal bottom 12 of the latter is formed a blind cylindrical recess 13 of smaller diameter.
  • the central part of the insert 14 forms a crater 15 the periphery of which is covered with a circular bead 16 electrically insulating zirconium oxide or hafnium oxide ( Figure 2). Thanks to the presence of the counterbore 11, this bead 16 does not protrude beyond the end face 9 of the support 10, so that the ignition of the arc by short circuit can continue to take place from reliably.
  • an oxidizing plasma gas which is for example air or oxygen

Abstract

The support for the electrode has at its end a cavity at the bottom of which there is an emissive insert made of zirconium of hafnium. A portion of the support end around the insert has at least a portion of an electroconductive material axially projecting with respect to the insert. Application to plasma cutting torches ignition by short-circuit.

Description

La présente invention est relative aux torches de travail à l'arc plasma à allumage par court-circuit. Elle concerne en premier lieu une électrode pour une telle torche, du type comprenant un support électroconducteur ayant une extrémité munie d'un insert émissif, notamment en zirconium ou en hafnium.The present invention relates to plasma arc work torches with short-circuit ignition. It relates firstly to an electrode for such a torch, of the type comprising an electroconductive support having an end provided with an emissive insert, in particular made of zirconium or hafnium.

Les torches de coupage plasma fonctionnant sous gaz plasmagène oxydant sont généralement équipées d'une cathode émissive en zirconium ou en hafnium, insérée dans une pièce en cuivre tenant lieu de support électroconducteur et de refroidisseur, l'ensemble étant communément appelé électrode.Plasma cutting torches operating under oxidizing plasma gas are generally equipped with an emissive cathode of zirconium or hafnium, inserted in a copper part acting as an electroconductive support and cooler, the assembly being commonly called electrode.

Lors du fonctionnement de la torche, la racine de l'arc s'accroche au centre de la cathode, où il se forme progressivement un cratère à la surface duquel se développe une couche d'oxyde de zirconium ou de hafnium. A chaud, cet oxyde est fluide et conducteur et permet l'émission cathodique. Lorsque l'arc plasma est interrompu, l'oxyde se solidifie et devient isolant. A la solidification, il se forme fréquemment, en périphérie du cratère, un bourrelet d'oxyde qui fait saillie sur la surface frontale de l'insert.During the operation of the torch, the root of the arc clings to the center of the cathode, where a crater gradually forms on the surface of which a layer of zirconium oxide or hafnium develops. When hot, this oxide is fluid and conductive and allows cathodic emission. When the plasma arc is interrupted, the oxide solidifies and becomes insulating. Upon solidification, an oxide bead frequently forms on the periphery of the crater, which protrudes from the front surface of the insert.

Dans les agencements connus, l'insert affleure la face d'extrémité du support. Par suite, le bourrelet d'oxyde fait saillie au-delà de cette face d'extrémité. Si ce bourrelet ne présente aucun caractère gênant dans le cas d'une torche conventionnelle, où électrode et tuyère sont fixes et où l'établissement de l'arc est initié par une décharge haute fréquence, dans le cas de torches à allumage par court-circuit, telles que décrites dans les documents FR-A-2 556 549 et 2 562 748, où l'allumage de l'arc est obtenu en réalisant un court-circuit entre l'électrode et la tuyère, il arrive que ce bourrelet d'oxyde forme une barrière électriquement isolante qui empêche le passage fiable du courant entre l'électrode et la tuyère et, par suite, l'allumage fiable de l'arc.In known arrangements, the insert is flush with the end face of the support. As a result, the oxide bead protrudes beyond this end face. If this bead has no annoying character in the case of a conventional torch, where the electrode and nozzle are fixed and where the establishment of the arc is initiated by a high frequency discharge, in the case of torches with short-ignition circuit, as described in documents FR-A-2 556 549 and 2 562 748, where the ignition of the arc is obtained by producing a short circuit between the electrode and the nozzle, it sometimes happens that this bead d The oxide forms an electrically insulating barrier which prevents the reliable passage of current between the electrode and the nozzle and, consequently, the reliable ignition of the arc.

L'invention a pour but d'améliorer la fiabilité de l'allumage de l'arc dans les torches à allumage par court-circuit, avec un agencement simple et n'obérant pas les coûts de fabrication des torches. A cet effet, elle a pour objet une électrode pour torche de travail à l'arc plasma, du type précité, caractérisée en ce qu'une partie de l'extrémité du support située autour de l'insert comporte au moins une portion en matériau électroconducteur faisant saillie axialement par rapport à l'insert.The object of the invention is to improve the reliability of the ignition of the arc in short-circuit ignition torches, with a simple arrangement and not incurring the costs of manufacturing the torches. To this end, it relates to an electrode for a plasma arc work torch, of the aforementioned type, characterized in that a part of the end of the support situated around the insert comprises at least one portion of material electroconductive protruding axially with respect to the insert.

Suivant des caractéristiques plus particulières :

  • la portion en saillie, avantageusement circulaire, est venue de matière avec le support ;
  • l'insert est monté dans un évidement ménagé dans le fond d'un lamage circulaire creusé dans la face d'extrémité du support.
According to more specific characteristics:
  • the projecting portion, advantageously circular, came integrally with the support;
  • the insert is mounted in a recess in the bottom of a circular counterbore hollowed out in the end face of the support.

L'invention a également pour objet une torche de travail à l'arc plasma, du type comprenant un corps de torche dans lequel une électrode ayant une face d'extrémité dans laquelle est monté un insert émissif, et une tuyère ayant une face interne en regard de la face d'extrémité, sont montées mobiles l'une par rapport à l'autre entre une première position de travail, où lesdites faces sont espacées l'une de l'autre et une seconde position où lesdites faces sont en contact mutuel, caractérisée en ce que, dans la seconde position, un espace est ménagé entre l'insert et la portion en regard de la face interne de la tuyère.The invention also relates to a plasma arc work torch, of the type comprising a torch body in which an electrode having an end face in which an emissive insert is mounted, and a nozzle having an internal face in look of the end face, are mounted movable relative to each other between a first working position, where said faces are spaced from each other and a second position where said faces are in mutual contact , characterized in that, in the second position, a space is provided between the insert and the portion facing the internal face of the nozzle.

Un exemple de réalisation de l'invention va maintenant être décrit en regard du dessin annexé, sur lequel :

  • la figure 1 est une vue schématique partielle en coupe axiale d'une torche de coupage plasma conforme à l'invention ; et
  • la figure 2 est une vue en coupe axiale à plus grande échelle de la partie d'extrémité de l'électrode.
An embodiment of the invention will now be described with reference to the attached drawing, in which:
  • Figure 1 is a partial schematic view in axial section of a plasma cutting torch according to the invention; and
  • Figure 2 is an axial sectional view on a larger scale of the end portion of the electrode.

La torche représentée à la figure 1 dans la mesure nécessaire à la compréhension de l'invention est pour l'essentiel celle décrite dans le document FR-A-2 556 549 précité. Elle possède une symétrie générale d'axe X-X supposé vertical et comprend un corps tubulaire 1 dans lequel est fixée une électrode axiale 2. Un porte-tuyère 3, vissé sur le corps 1, définit un épaulement de butée 4 pour une tuyère 5 en forme de coupelle montée coulissante axialement et sollicitée vers l'épaulement 4 par un ressort 6 et, en service, également par la pression du gaz plasmagène arrivant par l'espace annulaire 7 existant entre le corps 1 et l'électrode 2.The torch shown in Figure 1 to the extent necessary for understanding the invention is essentially that described in the document FR-A-2 556 549 cited above. It has a general symmetry of axis XX supposed to be vertical and comprises a tubular body 1 in which is fixed an axial electrode 2. A nozzle holder 3, screwed onto the body 1, defines an abutment shoulder 4 for a shaped nozzle 5 cup mounted sliding axially and biased towards the shoulder 4 by a spring 6 and, in service, also by the pressure of the plasma gas arriving through the annular space 7 existing between the body 1 and the electrode 2.

Ainsi la tuyère 5, qui est percée d'un trou axial central 8 pour la sortie de l'arc et du plasma, est mobile axialement entre une position normale de travail, telle que représentée, espacée de l'extrémité inférieure de l'électrode, et une seconde position d'allumage de l'arc par court-circuit, dans laquelle la face transversale interne de la tuyère vient en contact avec la face d'extrémité inférieure 9 de l'électrode en prenant appui sur la pièce métallique à découper (non représentée), une tension électrique étant appliquée entre l'électrode et cette pièce.Thus the nozzle 5, which is pierced with a central axial hole 8 for the exit of the arc and the plasma, is axially movable between a normal working position, as shown, spaced from the lower end of the electrode , and a second arc ignition position by short circuit, in which the internal transverse face of the nozzle comes into contact with the lower end face 9 of the electrode by pressing on the metal part to be cut (not shown), an electric voltage being applied between the electrode and this part.

L'électrode 2 comprend essentiellement un support électroconducteur en cuivre 10 dont la face d'extrémité 9 est plane et horizontale. Un lamage cylindrique 11 est usiné dans la face d'extrémité, et dans le fond plat et horizontal 12 de ce dernier est ménagé un évidement cylindrique borgne 13 de plus petit diamètre. Un insert émissif cathodique 14, constitué d'un bloc cylindrique en zirconium ou en hafnium, est emmanché à force dans l'évidement 13, affleurant avec le fond 12 du lamage ou faisant légèrement saillie par rapport à ce dernier. De cette façon, dans la seconde position, un espace axial est ménagé entre l'extrémité de l'insert 1 et la portion en regard de la face interne de la tuyère 5.The electrode 2 essentially comprises a copper electroconductive support 10, the end face 9 of which is flat and horizontal. A cylindrical counterbore 11 is machined in the end face, and in the flat and horizontal bottom 12 of the latter is formed a blind cylindrical recess 13 of smaller diameter. A cathode emissive insert 14, consisting of a cylindrical block of zirconium or hafnium, is force fitted into the recess 13, flush with the bottom 12 of the counterbore or slightly projecting from the latter. In this way, in the second position, an axial space is formed between the end of the insert 1 and the portion facing the internal face of the nozzle 5.

Après un certain temps d'utilisation avec un gaz plasmagène oxydant, qui est par exemple de l'air ou de l'oxygène, la partie centrale de l'insert 14 forme un cratère 15 dont la périphérie est recouverte d'un bourrelet circulaire 16 d'oxyde de zirconium ou de hafnium électriquement isolant à froid (figure 2). Grâce à la présence du lamage 11, ce bourrelet 16 ne fait pas saillie au-delà de la face d'extrémité 9 du support 10, de sorte que l'allumage de l'arc par court-circuit peut continuer de s'effectuer de façon fiable.After a certain period of use with an oxidizing plasma gas, which is for example air or oxygen, the central part of the insert 14 forms a crater 15 the periphery of which is covered with a circular bead 16 electrically insulating zirconium oxide or hafnium oxide (Figure 2). Thanks to the presence of the counterbore 11, this bead 16 does not protrude beyond the end face 9 of the support 10, so that the ignition of the arc by short circuit can continue to take place from reliably.

En variante, on comprend que le même résultat peut être obtenu lorsque le lamage est ménagé, avec un diamètre analogue, dans la face interne de la tuyère 5 tournée vers l'électrode, comme représenté en trait mixte en 11A à la figure 1, l'insert 13 pouvant alors être affleurant avec la face d'extrémité 9 de la cathode.As a variant, it is understood that the same result can be obtained when the counterbore is formed, with a similar diameter, in the internal face of the nozzle 5 facing the electrode, as shown in phantom in 11A in FIG. 1, l insert 13 can then be flush with the end face 9 of the cathode.

Claims (9)

  1. An electrode for a torch for plasma arc work with short-circuit ignition, of the type comprising an electro-conductive support (10) having an end provided with an emitting insert (14), particularly one made of zirconium or hafnium, characterised in that part of the end of the support located around the insert (14) comprises at least one portion made of an electro-conductive material projecting axially relative to the insert.
  2. An electrode according to Claim 1, characterised in that the projecting portion is circular.
  3. An electrode according to Claim 1 or Claim 2, characterised in that the projecting portion comes from the same substance as the support (10).
  4. An electrode according to Claim 3, characterised in that the insert (14) is mounted inside a recess (13) made at the bottom of a circular spotface (11) hollowed out in the end face (9) of the support (10).
  5. An electrode according to Claim 4, characterised in that the diameter of the spotface (11) is greater than that of the recess (13).
  6. A torch for plasma arc work, of the type comprising a torch body (1) in which an electrode (2), having an end face (9) in which an emitting insert (16) is mounted, and a nozzle (5), having an inner face facing the end face, are mounted so as to be mobile relative to each other between a first working position, where said faces are at a distance from one another and a second, arcing position, where the faces are in mutual contact, characterised in that, in the second position, a space is made between the insert (16) and the portion (9) facing the inner face of the nozzle (5).
  7. A torch according to Claim 6, characterised in that the electrode is shaped according to one of Claims 1 to 5.
  8. A torch according to Claim 6, characterised in that the portion facing the inner face of the nozzle (5) stands back relative to this inner face.
  9. A torch according to Claim 8, characterised in that the facing portion is constituted by the bottom of a spot-face (11) formed in the inner face of the nozzle (5).
EP90402132A 1989-07-28 1990-07-25 Electrode for plasma arc torch, and torch using such an electrode Expired - Lifetime EP0410875B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT90402132T ATE102431T1 (en) 1989-07-28 1990-07-25 PLASMA ARC TORCH ELECTRODE AND RELATIVE TORCH.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8910224A FR2650470B1 (en) 1989-07-28 1989-07-28
FR8910224 1989-07-28

Publications (2)

Publication Number Publication Date
EP0410875A1 EP0410875A1 (en) 1991-01-30
EP0410875B1 true EP0410875B1 (en) 1994-03-02

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Application Number Title Priority Date Filing Date
EP90402132A Expired - Lifetime EP0410875B1 (en) 1989-07-28 1990-07-25 Electrode for plasma arc torch, and torch using such an electrode

Country Status (10)

Country Link
US (1) US5083005A (en)
EP (1) EP0410875B1 (en)
JP (1) JPH0642991B2 (en)
KR (1) KR910004074A (en)
AT (1) ATE102431T1 (en)
CA (1) CA2021836C (en)
DE (1) DE69006965D1 (en)
FR (1) FR2650470B1 (en)
NO (1) NO903178L (en)
PT (1) PT94835B (en)

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RU2172662C1 (en) * 2000-08-29 2001-08-27 Осинцев Григорий Владиславович Electrode for plasma working

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IT1243170B (en) * 1990-11-29 1994-05-24 Trafimet Trafilerie Metalliche PLASMA CUTTING TORCH WITH TRIGGER FOR CONTACT
FR2735710B1 (en) * 1995-06-23 1997-07-25 Soudure Autogene Francaise PLASMA TORCH HEAD AND PLASMA TORCH COMPRISING THE SAME
US5897795A (en) * 1996-10-08 1999-04-27 Hypertherm, Inc. Integral spring consumables for plasma arc torch using blow forward contact starting system
US5994663A (en) * 1996-10-08 1999-11-30 Hypertherm, Inc. Plasma arc torch and method using blow forward contact starting system
US5886315A (en) * 1997-08-01 1999-03-23 Hypertherm, Inc. Blow forward contact start plasma arc torch with distributed nozzle support
AU9477598A (en) * 1997-09-10 1999-03-29 Esab Group, Inc., The Electrode with emissive element having conductive portions
US6703581B2 (en) 2001-02-27 2004-03-09 Thermal Dynamics Corporation Contact start plasma torch
US20070045241A1 (en) * 2005-08-29 2007-03-01 Schneider Joseph C Contact start plasma torch and method of operation
US8101882B2 (en) * 2005-09-07 2012-01-24 Hypertherm, Inc. Plasma torch electrode with improved insert configurations
DE102008062731C5 (en) 2008-12-18 2012-06-14 Kjellberg Finsterwalde Plasma Und Maschinen Gmbh Electrode for a plasma torch
US8362387B2 (en) 2010-12-03 2013-01-29 Kaliburn, Inc. Electrode for plasma arc torch and related plasma arc torch
MX2013007668A (en) * 2011-02-28 2013-12-06 Thermal Dynamics Corp Method of manufacturing a high current electrode for a plasma arc torch.
US9949356B2 (en) * 2012-07-11 2018-04-17 Lincoln Global, Inc. Electrode for a plasma arc cutting torch
KR101942019B1 (en) * 2017-09-12 2019-01-24 황원규 Plasma torch
CN113038680B (en) * 2021-02-05 2022-06-28 浙江大学 Arc ablation resistant electrode structure and preparation method thereof

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US4059743A (en) * 1974-10-28 1977-11-22 Eduard Migranovich Esibian Plasma arc cutting torch
FR2556549B1 (en) * 1983-12-07 1986-10-17 Soudure Autogene Francaise METHOD OF LIGHTING AN ARC FOR A WELDING OR CUTTING TORCH AND TORCH SUITABLE FOR CARRYING OUT THIS METHOD
SE452862B (en) * 1985-06-05 1987-12-21 Aga Ab LIGHT BAGS LEAD
US4810851A (en) * 1985-07-22 1989-03-07 Gossudarsvenny Proektny i Nauchno-Issledovatelsky Institute Nikelevo-Kobaltovoi Promyshylennosti Method of constantly restoring an electrode during plasma treatment of materials
US4769524A (en) * 1987-10-23 1988-09-06 Hardwick Steven F Plasma electrode
US4864097A (en) * 1988-09-23 1989-09-05 Emerson Electric Co. Plasma arc torch with confined and controlled plasma jet column

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2172662C1 (en) * 2000-08-29 2001-08-27 Осинцев Григорий Владиславович Electrode for plasma working

Also Published As

Publication number Publication date
US5083005A (en) 1992-01-21
NO903178D0 (en) 1990-07-17
EP0410875A1 (en) 1991-01-30
ATE102431T1 (en) 1994-03-15
CA2021836A1 (en) 1991-01-29
JPH03151169A (en) 1991-06-27
CA2021836C (en) 1995-12-19
PT94835A (en) 1992-02-28
JPH0642991B2 (en) 1994-06-08
KR910004074A (en) 1991-02-28
FR2650470B1 (en) 1992-09-04
PT94835B (en) 1997-05-28
FR2650470A1 (en) 1991-02-01
NO903178L (en) 1991-01-29
DE69006965D1 (en) 1994-04-07

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