WO1990006666A1 - Chalumeau a plasma a refroidissement par liquide avec arc de transfert - Google Patents

Chalumeau a plasma a refroidissement par liquide avec arc de transfert Download PDF

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Publication number
WO1990006666A1
WO1990006666A1 PCT/DE1989/000744 DE8900744W WO9006666A1 WO 1990006666 A1 WO1990006666 A1 WO 1990006666A1 DE 8900744 W DE8900744 W DE 8900744W WO 9006666 A1 WO9006666 A1 WO 9006666A1
Authority
WO
WIPO (PCT)
Prior art keywords
plasma torch
ignition
torch according
main electrode
electrode
Prior art date
Application number
PCT/DE1989/000744
Other languages
German (de)
English (en)
Inventor
Hans-Josef Bebber
Heinrich-Otto Rossner
Gebhard Tomalla
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
Priority to EP89912979A priority Critical patent/EP0446238B1/fr
Priority to KR1019900701563A priority patent/KR900702756A/ko
Priority to DE58908219T priority patent/DE58908219D1/de
Publication of WO1990006666A1 publication Critical patent/WO1990006666A1/fr
Priority to NO912076A priority patent/NO169870C/no

Links

Classifications

    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00Generating plasma; Handling plasma
    • H05H1/24Generating plasma
    • H05H1/26Plasma torches
    • H05H1/28Cooling arrangements
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00Generating plasma; Handling plasma
    • H05H1/24Generating plasma
    • H05H1/26Plasma torches
    • H05H1/32Plasma torches using an arc
    • H05H1/34Details, e.g. electrodes, nozzles
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00Generating plasma; Handling plasma
    • H05H1/24Generating plasma
    • H05H1/26Plasma torches
    • H05H1/32Plasma torches using an arc
    • H05H1/34Details, e.g. electrodes, nozzles
    • H05H1/341Arrangements for providing coaxial protecting fluids
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00Generating plasma; Handling plasma
    • H05H1/24Generating plasma
    • H05H1/26Plasma torches
    • H05H1/32Plasma torches using an arc
    • H05H1/34Details, e.g. electrodes, nozzles
    • H05H1/3421Transferred arc or pilot arc mode
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05HPLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
    • H05H1/00Generating plasma; Handling plasma
    • H05H1/24Generating plasma
    • H05H1/26Plasma torches
    • H05H1/32Plasma torches using an arc
    • H05H1/34Details, e.g. electrodes, nozzles
    • H05H1/3478Geometrical details

Definitions

  • the invention relates to a liquid-cooled plasma torch with a transmitted arc, the cooling liquid, electricity and gas are led to the ignition and main electrodes via ignition and main electrode lances consisting of coaxial tubes.
  • Plasma torches of this type are e.g. Known from DE-OS 29 00 330 and consist essentially of the main components burner jacket with nozzle, main electrode lance with main electrode and ignition electrode lance with ignition electrode.
  • both the ignition electrode lance and the main electrode lance are each liquid-cooled; each lance consists of tubes which are arranged coaxially to each other.
  • the outer tube of the ignition electrode lance is for. Ignition electrode closed on the end and receives the ignition electrode.
  • the inner tube of the ignition electrode lance leaves a gap to the end wall of the outer tube or the ignition electrode, through which the connection for the cooling liquid between the central bore of the inner tube and the annular channel between the inner tube and the outer tube
  • the outer tube of the ignition electrode is guided via electrically insulating spacers or sleeves in the inner tube of the main electrode lance.
  • the ignition plasma gas is conducted to the ignition electrode and the central bore of the main electrode which surrounds it and is formed between the outer tube and the ignition electrode lance and the inner tube of the main electrode lance.
  • a main electrode lance consisting of three coaxially arranged tubes is used for cooling the main electrode. This creates a flow and return ring channel for the coolant diverted to the inner end wall of the main electrode.
  • the main electrode can be supplied with current via the inner and / or outer tube of the main electrode lance.
  • the electrical insulation between the outer tube of the main electrode lance and the inner tube of the burner jacket and the nozzle is carried out by means of spacers in the manner described above with respect to the end electrode lance.
  • the main plasma gas is also conducted into the area between the main electrode and the nozzle.
  • the plasma burners known from the prior art are structurally very complex and have relatively high heat losses along their lateral surfaces.
  • the ignition electrode lance is sealed off from the coolant channels and is electrically insulated from the main electrode lance or main electrode, the ignition gas can be conducted directly in the ignition electrode lance, which is simultaneously cooled from the outside.
  • the main electrode and ignition electrode lance preferably consist of a total of only three coaxially arranged to each other
  • Spare sheet Pipes wherein the cooling liquid is guided in the interconnected ring channels between the outer tube and the center tube on the one hand and between the center tube and the inner tube on the other hand. This takes into account the fact that the main electrode is the component that requires the greatest cooling.
  • the main electrode current is conducted through the outer tube and the ignition electrode current through the inner tube.
  • a correspondingly thin-walled insulation hose is selected, which, however, should preferably be highly elastic and resistant to high temperatures.
  • One or more sleeves are used to center the ignition electrode lance.
  • the center tube is continued in the area of the main electrode by an essentially ring-shaped deflection part, which at the end leaves a connection between the coolant ring channels lying on both sides of it free.
  • the center tube, the mentioned deflection part and the sleeve for centering the ignition electrode lance are made of non-conductive material, preferably plastic. This prevents a possible reduction in contact resistance between the ignition and main electrodes caused by the cooling medium.
  • the ignition electrode and the gas nozzle, into which the cylindrical interior of the ignition electrode lance merges are electrically conductive.
  • the nozzle effect of the gas nozzle is favored in that the corresponding pilot gas guide channels conically are guided outside, preferably in the form of several individual bores which are brought together again in the area of the main electrode or the outlet.
  • the gas nozzle and the main electrode are connected to one another via an annular insulating sleeve, which sleeve can consist of a high-temperature-resistant plastic, a hydraulic fluid-tight ceramic or a composite material made of a plastic, a metal and a ceramic.
  • the insulation hose is guided overlapping and sealingly over the gas nozzle and part of the insulation sleeve in order to improve the liquid insulation.
  • the O-ring seal provided between the outer surface of the gas nozzle and the inner surface of the insulating sleeve, which lies in a corresponding groove in the gas nozzle, optimizes the tightness.
  • the main electrode itself is pot-shaped and electrically connected to the outer tube. An O-ring seal is used between these parts for tightness. Another O-ring seal is located in the overlap area of the insulating sleeve and the main electrode.
  • the ignition electrode should be made of tungsten, whereby for technical reasons the upper electrode of the ignition cone can be cast around with copper and the casting block in question forms the gas nozzle.
  • the inner tube is flared in the lower part and adapted to the taper of the subsequent holes.
  • Fig. 1 shows a plasma torch according to the invention in a longitudinal section
  • Fig. 2 shows the attachment of the ignition electrode in a longitudinal section in an enlarged view.
  • the main components of the plasma torch are an ignition or auxiliary electrode 11, a main or nozzle electrode 12 and a nozzle 13, which are each electrically insulated from one another.
  • the gas nozzle 14 has several, for example ten holes or through holes 19 evenly distributed on the circumference.
  • the axes of the bores 19 are arranged on an (imaginary) conical surface (19 ') such that the bores 19 are closer together at their end facing the tube 16 (than at their end facing the ignition electrode 11) and with their end facing the tube 16 End overall within
  • the cone angle of the (imaginary) conical surface 19 ' is denoted by ⁇ in FIG. 2.
  • the inner tube 16 is preferably made of copper, while the ignition electrode 11 is made of tungsten. It is advisable to prefabricate the ignition electrode 11 as a semifinished product as follows: the ignition electrode? Il is prepared into a rod with a cone II 1 with a cone angle and then in the casting process with copper in the dimensions required for the gas nozzle 14 cast around. The semi-finished product thus produced is finished by manufacturing the bores 19 and connected to the tube 16.
  • the outside of the gas nozzle 14 is surrounded by one end of an electrically insulating sleeve 20.
  • the insulating sleeve 20 encloses a cylindrical flange 21 of the main electrode 12.
  • the gas nozzle 14 and the main electrode 12 are kept at a distance with their flange 21 by an annular projection 22 on the inside of the sleeve 20.
  • the insulating sleeve 20 therefore serves as a mechanical
  • the insulating sleeve 20 is preferably made of a high-temperature-resistant plastic and / or hydraulic fluid-tight ceramic or a composite of plastic, metal and ceramic.
  • the main electrode 12 has a central passage 23 which, over a partial length, in particular in the region of the cylindrical flange 21, forms an annular channel 24 with the outer surface of the ignition electrode 11.
  • the inside diameter of the annular projection 22 is equal to the inside diameter of the adjoining flange 21 or the passage 23 of the main electrode 12.
  • the bores 19 all lie within the area given by this diameter.
  • the tube 16 is covered on its outside by an easily mountable and removable thin-walled, high-temperature-resistant and highly elastic insulation hose 25, which still surrounds the gas nozzle 14 and part of the insulating sleeve 20 in a ring.
  • an electrically insulating coating can also be provided.
  • the main electrode 12 is connected to an outer cylindrical part 26 in a current-conducting and pressure-fluid-tight manner with a tube 28.
  • a further tube 27 is arranged between the tube 28 and the tube 16 and carries a deflection part 29 at its lower end.
  • the tubes 16, 27, 28 are also referred to below as the inner tube 16, middle tube 27 and outer tube 28.
  • the inner tube 16 with the gas nozzle 14 represents the ignition electrode lance and these form the main electrode lance together with the sleeve 20 and the central and outer tubes 27 and 28.
  • sleeves 31 made of electrically insulating material and having axially parallel passages are used, which abut on the one hand on the insulation tube 25 and on the other hand on the inside of the center tube 27.
  • the center tube 27 and the adjoining deflection part 29 as well as the centering sleeves 31 are preferably made of plastic, which in addition to the electrical insulation brings weight savings.
  • the gas flow for the ignition electrode 11 takes place via the symbolically indicated ignition gas connection 32, the cavity 17, the bores 19 and the ring channel 24.
  • the ignition electrode lance formed by the tube 16 is cooled on the inside by the cold ignition plasma gas.
  • the ignition plasma gas emerges as a plasma jet from the central bore 23 of the main electrode 12.
  • the flow of gas for between the main electrode 12 and another pole, e.g. a metal melt, main or power arc to be ignited takes place via the symbolically indicated plasma gas connection 33 and the
  • Spare sheet Annular channel 34 which is formed by the outer surface of the outer tube 28 and the main electrode 12 on the one hand and the inner surface of the burner jacket and the nozzle 13 on the other hand.
  • annular channel 35 and 36 for the flow of a liquid coolant. Both ring channels 35, 36 are connected to one another between the deflection part 29 and the end part of the main electrode 12. The ignition electrode lance formed by the inner tube 16 is also detected by the coolant flow.
  • the ignition electrode 11 is electrically connected to a pole of a (not shown) current or voltage source via the gas nozzle 14, the inner tube 16 and the symbolically indicated current connection 37 located thereon.
  • the main electrode 12 is connected to another pole of the current or voltage source via the outer tube 28 and the current connection 39 located there, which is also symbolically indicated.
  • a liquid coolant is introduced into the ring channel 35 via the symbolically indicated coolant connection or inlet 41 and is returned under the deflection part 29 through the ring channel 36 to the symbolically indicated coolant outflow or outlet 43 .
  • the outer tube 28 carrying the current to the main electrode 12 is cooled internally by the water supply. In addition, the outer tube 28 through the
  • Spare sheet Main electrode 12 cooled by the main channel 34 flowing cold main plasma gas.
  • seals in the form of O-rings are each between the sleeve 20 and the gas nozzle 14 (O-ring 45) and the cylindrical inner flange 21 of the main electrode 12 (O-ring 46) and between the outer flange 26 of the main electrode and the outer tube 28 (O-ring 47) provided.
  • the O-rings 45 ... 7 are held in annular grooves, of which in FIG. 2 the annular groove 48 in the gas nozzle 14 for the O-ring 45 and the annular groove 49 in the sleeve 20 for the O-ring 46 are exemplary are shown.
  • the inner tube 16 is also cooled by the plasma gas flowing through its cavity 17.
  • the plasma torch described is preferably operated as a three-phase plasma torch. But he can also. can also be operated with direct and / or alternating current as described in EP-OS 0 134 961 A2.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Geometry (AREA)
  • Plasma Technology (AREA)
  • Gas Burners (AREA)
  • Gasification And Melting Of Waste (AREA)
  • Discharge Heating (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)

Abstract

L'invention concerne un chalumeau à plasma à refroidissement par liquide avec arc de transfert, dont le liquide de refroidissement, le courant électrique et le gaz sont amenés par l'intermédiaire d'une lance d'électrode d'amorçage et d'une lance d'électrode principale formées de tubes coaxiaux vers l'électrode d'amorçage et l'électrode principale. Pour améliorer la construction du chalumeau, réduire au minimum les pertes thermiques de son enveloppe et accroître le rendement dudit chalumeau, il est proposé de réaliser un circuit de liquide de refroidissement commun (41, 35, 36, 43) pour la lance de l'électrode d'amorçage (16) et la lance de l'électrode principale (27, 28).
PCT/DE1989/000744 1988-12-01 1989-11-24 Chalumeau a plasma a refroidissement par liquide avec arc de transfert WO1990006666A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP89912979A EP0446238B1 (fr) 1988-12-01 1989-11-24 Chalumeau a plasma a refroidissement par liquide avec arc de transfert
KR1019900701563A KR900702756A (ko) 1988-12-01 1989-11-24 이동전호를 구비한 액체로 냉각된 플라즈마 토치
DE58908219T DE58908219D1 (de) 1988-12-01 1989-11-24 Flüssigkeitsgekühlter plasmabrenner mit übertragenem lichtbogen.
NO912076A NO169870C (no) 1988-12-01 1991-05-29 Vaeskeavkjoelt plasmabrenner med overfoert lysbue.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3840485A DE3840485A1 (de) 1988-12-01 1988-12-01 Fluessigkeitsgekuehlter plasmabrenner mit uebertragenem lichtbogen
DEP3840485.0 1988-12-01

Publications (1)

Publication Number Publication Date
WO1990006666A1 true WO1990006666A1 (fr) 1990-06-14

Family

ID=6368234

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE1989/000744 WO1990006666A1 (fr) 1988-12-01 1989-11-24 Chalumeau a plasma a refroidissement par liquide avec arc de transfert

Country Status (10)

Country Link
EP (1) EP0446238B1 (fr)
JP (1) JP2942354B2 (fr)
KR (1) KR900702756A (fr)
AT (1) ATE110221T1 (fr)
CA (1) CA2004226A1 (fr)
DD (1) DD292806A5 (fr)
DE (2) DE3840485A1 (fr)
ES (1) ES2017440A6 (fr)
WO (1) WO1990006666A1 (fr)
ZA (1) ZA899174B (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992008335A1 (fr) * 1990-10-30 1992-05-14 Mannesmann Ag Chalumeau a plasma pour la fusion et le maintien a la temperature requise de materiaux a traiter dans des recipients
JP2012523651A (ja) * 2009-04-08 2012-10-04 シェルベリ フィンスターヴァルデ プラスマ ウント マシーネン ゲーエムベーハー アークプラズマトーチのための冷却管、電極保持具および電極、並びにその構成およびそれらを備えたアークプラズマトーチ

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4022112C2 (de) * 1990-07-11 1996-03-14 Mannesmann Ag Plasmabrenner für übertragenen Lichtbogen
NO174450C (no) * 1991-12-12 1994-05-04 Kvaerner Eng Anordning ved plasmabrenner for kjemiske prosesser
WO2002068872A1 (fr) 2001-02-27 2002-09-06 Yantai Longyuan Power Technology Co., Ltd. Ensemble cathode et allumeur a plasma pourvu d'un tel ensemble cathode
KR100708320B1 (ko) * 2004-04-22 2007-04-17 김기현 대기압 마이크로웨이브 플라즈마를 이용한 외장재 부품표면개질 장치 및 방법
JP4820317B2 (ja) * 2006-04-06 2011-11-24 積水化学工業株式会社 放電処理装置
JP4576476B1 (ja) * 2009-12-28 2010-11-10 株式会社フェローテック ストライカ式プラズマ発生装置及びプラズマ処理装置
JP6522968B2 (ja) 2015-01-30 2019-05-29 株式会社小松製作所 プラズマトーチ用絶縁ガイド、及び交換部品ユニット
CN107509299B (zh) * 2016-02-22 2019-03-12 衢州迪升工业设计有限公司 一种电离协同的热解装置
DE202017000969U1 (de) 2017-02-23 2017-04-03 CEBra - Centrum für Energietechnologie Brandenburg GmbH Hochspannungszündvorrichtung

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3569661A (en) * 1969-06-09 1971-03-09 Air Prod & Chem Method and apparatus for establishing a cathode stabilized (collimated) plasma arc
US4055741A (en) * 1975-12-08 1977-10-25 David Grigorievich Bykhovsky Plasma arc torch
US4564740A (en) * 1978-01-09 1986-01-14 Institut Elektrosvarki Imeni E. O. Patona Akademii Nauk Ukrainskoi Ssr Method of generating plasma in a plasma-arc torch and an arrangement for effecting same

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO119341B (fr) * 1965-04-09 1970-05-04 Inst Badan Jadrowych
US4549065A (en) * 1983-01-21 1985-10-22 Technology Application Services Corporation Plasma generator and method
DE3435680A1 (de) * 1984-09-28 1986-04-03 Fried. Krupp Gmbh, 4300 Essen Plasmabrenner
DE3642375A1 (de) * 1986-12-11 1988-06-23 Castolin Sa Verfahren zur aufbringung einer innenbeschichtung in rohre od. dgl. hohlraeume engen querschnittes sowie plasmaspritzbrenner dafuer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3569661A (en) * 1969-06-09 1971-03-09 Air Prod & Chem Method and apparatus for establishing a cathode stabilized (collimated) plasma arc
US4055741A (en) * 1975-12-08 1977-10-25 David Grigorievich Bykhovsky Plasma arc torch
US4564740A (en) * 1978-01-09 1986-01-14 Institut Elektrosvarki Imeni E. O. Patona Akademii Nauk Ukrainskoi Ssr Method of generating plasma in a plasma-arc torch and an arrangement for effecting same

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1992008335A1 (fr) * 1990-10-30 1992-05-14 Mannesmann Ag Chalumeau a plasma pour la fusion et le maintien a la temperature requise de materiaux a traiter dans des recipients
US5406047A (en) * 1990-10-30 1995-04-11 Mannesmann Aktiengesellschaft Plasma torch for melting material to be processed in a container and for maintaining the material at the required temperature
JP2012523651A (ja) * 2009-04-08 2012-10-04 シェルベリ フィンスターヴァルデ プラスマ ウント マシーネン ゲーエムベーハー アークプラズマトーチのための冷却管、電極保持具および電極、並びにその構成およびそれらを備えたアークプラズマトーチ

Also Published As

Publication number Publication date
ATE110221T1 (de) 1994-09-15
CA2004226A1 (fr) 1990-06-01
EP0446238A1 (fr) 1991-09-18
ES2017440A6 (es) 1991-02-01
DE3840485A1 (de) 1990-06-07
DD292806A5 (de) 1991-08-08
EP0446238B1 (fr) 1994-08-17
JP2942354B2 (ja) 1999-08-30
DE58908219D1 (de) 1994-09-22
ZA899174B (en) 1990-09-26
KR900702756A (ko) 1990-12-08
JPH04502531A (ja) 1992-05-07

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