US3858072A - Plasma torch with axial supply of the stabilizing gas - Google Patents

Plasma torch with axial supply of the stabilizing gas Download PDF

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Publication number
US3858072A
US3858072A US00330026A US33002673A US3858072A US 3858072 A US3858072 A US 3858072A US 00330026 A US00330026 A US 00330026A US 33002673 A US33002673 A US 33002673A US 3858072 A US3858072 A US 3858072A
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United States
Prior art keywords
cathode
anode
nozzle
tube
holder
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Expired - Lifetime
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US00330026A
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English (en)
Inventor
V Dembovsky
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VYSOKA SKOLA BANSKA OSTRAVA
VYSOKA SKOLA BANSKA OSTRAVA CS
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VYSOKA SKOLA BANSKA OSTRAVA
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    • 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
    • H05H1/28—Cooling arrangements

Definitions

  • ABSTRACT A plasma torch with an internal cathode and an exter- [73] Assignee: Vysoka skola banska Ostrava,
  • the invention relates to a plasma torch with are discharge and axial supply of the stabilizing gas solving the adjustment of the supply of the stabilizing gas, the adjustment of the distance of the cathode from the anode with a possibility of starting by short circuiting the cathode and anode and with a direct and intensive cooling of the nozzle.
  • Known plasma torches have either an axial or tangential supply of the stabilizing gas.
  • the supply means of the stabilizing gas are generally stable and are suitable for certain operating conditions of the plasma torch .Within a relatively narrow range of speeds of the gaseous medium in the discharge chambers.
  • the selection of the distance of the cathode from the anode has been for known plasma torches determined without regard to the circumstance that by changes of this distance, changes of the flow of the gas along the cathode are resulting, reducing the efficiency of burning of the torch.
  • the electric are discharge is for actually known plasma burners started either by a purposely made short circuit between the cathode and anode either directly or by means of a wire of a metal with low melting point or by means of an auxiliary discharge between an auxiliary cathode and the anode of the plasma torch.
  • the electric arc discharge can be also started by means of a high frequency or high voltage current causing a high frequency or high voltage discharge in the discharge chamber, which causes ionization of the operating space and enables starting of the electric arc discharge by the electric current supplied by the DC or AC main supply source.
  • the stabilizing gas is supplied to the nozzle at known plasma torches via an annular space, between the external cylindrical surface of the cathode and the internal surface of the nozzle.
  • This arrangement of the gas supply however does not solve a uniform passage of the gas along the cathode, a sufficient cooling of its surface by the working gas and equally does not solve a centric discharge of the plasma from nozzles with a larger diameter;
  • the flow of the cooling liquid uses to be arranged for dirrectly cooled nozzles by means of channels, supplying the cooling liquid which comes in contact with a part of the nozzle only or free spaces around the nozzle are formed through which the cool- SUMMARY OF THE INVENTION It is an object of this invention to eliminate the drawbacks of existing plasma torches and to enable an easy adjustment of the torch to different working conditions at an efficient cooling of the nozzle with an easy starting of the arc discharge.
  • the torch according to this invention has an axial supply of a stabilizing gas, a cathode displaceable in the axial direction and a nozzle cooled by a through flowing cooling medium, the cathode having on its surface longitudinal grooves, a distributing insert being provided between the external mantle of the torch and an internal tube of the torchjoined to the nozzle, the internal diameter of said distributing insert being larger than the diameter of the external wall of the internal tube, while the external diameter of the distribution insert is smaller than the diameter of the internal wall of the external mantle, a gap for the passage of the cooling liquid being provided between the front face of the nozzle and the front face of the distribution insert, the torch head housing a distribution chamber arranged axially slidable in the torch head and bearing a tubular holder of the carhode and another tube of electrically insulating material, surrounding this tubular holder, the space between the tubular holder and the electrically insulating tube serving for the supply of the stabilizing gas, the torch head consisting of a
  • one plasma burner can be used with very small and with large amounts of working gas while using nozzles of different diameter.
  • FIG. 1 is a longitudinal sectional schematic view of the whole torch
  • FIG. 2 the arrangement of the cathode with longitudinal surface grooves and of the nozzle with the distribution inlet in elevation with parts in longitudinal sectional view
  • FIG. 3 a cross section along a plane indicated in FIG. 2 by A-A showing the mutual arrangement of the cathode, the nozzle and the distribution inlet.
  • the plasma torch according to this invention has a nozzle 1 functioning as an anode and joined to two concentric metal tubes, forming the external mantle 21 of the whole torch and an internal tube 22, furthermore a cathode 3 fixed on an electrically conductive holder 6 of the cathode 3.
  • the nozzle 1 of the plasma torch is made of copper or of some metal having a high melting point and is intensively cooled by some liquid flowing along its internal surface as indicated by arrows. A sufficient speed of the flowing liquid at the internal surface of the nozzle 1 is secured by a distributing insert 23 fixed to a separating tube 2 arranged concentrically between the external mantle 21 and the internal tube 22 of the torch.
  • the separating tube 2 is secured in the sleeve and simultaneously constitutes a reinforcing part of the distributing insert 23.
  • the separating tube 2 is constructionally different from the external mantle 21.
  • the separating tube 2 is fixed to the sleeve 9.
  • the supply and removal of the cooling liquid to and from the nozzle is achieved by the inlet 7 and by the outlet 8 respectively of the cooling liquid.
  • the cathode 3 which is affixed to the holder 6 is made of a high melting metal, is hollow and is cooled by liquid which is supplied to its working end via an inlet tube 4, and is removed over the outlet20 of cooling liquid of the cathode 3.
  • the nozzle 1 functions as an anode, during the starting period the positive pole of an auxiliary DC. current source being connected to the nozzle.
  • an independent arc burns between the anode, that is the nozzle 1, and the cathode 3.
  • the independent arc enables the creation or ignition of an independent arc buring between the cathode and the material to be smelted.
  • the dependent arc stabilized by the gas, then burns through the nozzle 1.
  • the stabilizing gas is supplied to a distribution chamber 16 via a gas inlet 17, wherefrom it passes to the discharge chamber of the torch along a tube of electrically insulating material fixed to the distribution chamber 16.
  • the space defined between the holder 6 of the cathode 3 and the tube 5 forms an axial gas supply.
  • the torch head proper consists of the sleeve 9, of a nut 12 and a closure 15 and houses a device for adjustment of the supply of the stabilizing gas and a mechanism for starting and for adjustment of the distance of the cathode 3 from the nozzle 1.
  • This adjustment of the distance of the cathode 3 from the nozzle is accomplished by turning the nut 12 provided on both ends with right and left hand threads.
  • the distance between the closure 15 and the sleeve 9 is changing, whereby simultaneously the distribution chamber 16 is axially displaced, its constant contact with the bottom of the closure being secured by the pressure of the spring 14 acting on the distribution chamber 16 by way of a washer 13 of electrically insulating material.
  • the porcelaine tube 5 connected therewith is displaced, along which'stabilizing gas is supplied to the nozzle of the torch and equally also the holder 6 with the cathode 3.
  • the movement of the distribution chamber 16 is transmitted to the holder 6 of the cathode 3 by three set screws 18.
  • the lower end of the tube or holder 6 which forms the cathode 3 is of smaller diameter than the holder 6, the cathode being joined to the holder 6 by a frustoconical portion, as shown.
  • the anode is formed as a lower end of the tube 22, such lower end being of smaller diameter than the upper, main portion of such tube.
  • the lower and upper portions of tube 22 are joined by a frusto-conical portion which is coaxial of the frusto-conical portion of the cathode. the two frusto-conical portions having substantially the same apex angle. As will be seen in FIG.
  • the upper, largerdiametered end of the frusto-conical portion of cathode 3 has substantially the same diameter as the lower, smaller-diametered end of the frusto-conical portion of the nozzle 1. It can be seen from the above that the adjustment of the effective distance between the cathode 3 and the anode 1, that is the length of the gap between the frusto-conical portions thereof, is performed by adjusting the nut 12. The adjustment of the distance between the working end of the cathode 3 and the mouth of the stabilizing gas supply is carried out after loosening the screws 18in such way that the cathode is retracted into or extended out of the tube 5 which constitutes the supply of the stabilizing gas.
  • FIG. 2 shows the arrangement of the cathode with longitudinal grooves on its surface and of the nozzle provided with the distributing insert.
  • the cathode 3 has longitudinal grooves 26 for the passage of the gas C and is by means of the tube 5 from electrically insulating material centrically guided in the nozzle 1.
  • the nozzle ll of the plasma torch has a front face with a rim, provided on its circumference with a packing ring 27 of rubber.
  • the distribution insert 23 engages with its extremity into the cavity formed by this rim, determining the coaxial position of the distribution insert 23 with the whole torch.
  • Channels 24 are provided on the external circumference of the distribution insert 23 enabling access of the cooling liquid B to the working surface of the nozzle 1.
  • FIG. 2 shows one possible arrangement of the channels 214 in the distribution inserts 23 in cross section including a part of the torch.
  • the nut 12 and the closure 15 are made of electrically insulating material.
  • the porcelaine tube 5 is sealed by a packing ring 10.
  • An optimum adjustment of the gas supply and of the working end of the cathode 3 can be accomplished after loosening the set screws 18.
  • the sealing of the holder 6 of the cathode 3 is accomplished by a packing ring 19.
  • the starting of the torch is performed either by the use of an ionizer or by pressing the holder 6 of the cathode 3 in direction towards the nozzle 1 against the force of the spring 14 resting against the washer 11 made of electrically insulating material.
  • the cathode 3 is thrust downwardly (FIG.
  • connection of the plasma torch to the source of electric current is made by terminals on the external mantle 21 and on the holder 6 of the cathode 3.
  • the possibilities of application and the range of output of the plasma torch can be changed by changing the size of the nozzle 1, of the cathode 3 and of the distribution insert 23.
  • the described plasma torch is suitable for cutting of ferrous and non ferrous metals and alloys, for welding of steel, of non ferrous alloys and of metals with high melting point such as molybdenum, tungsten and similar.
  • This arrangement of the plasma torch is particularly suitable for band raffination and for melting of metallic material having a medium or high melting point. After adjustment of the nozzle the torch is also suitable for spray coating with layers of metal or of oxides.
  • Plasma torch with axial supply of a stabilizing gas comprising in combination:
  • a torch head comprising a sleeve, a cover and a nut connecting both the sleeve and cover, the nut enabling an adjustment of the axial distance between the cover and the sleeve,
  • a nozzle forming the anode of the torch connected by an internal tube and an external coaxial mantle with the sleeve,
  • a coaxial separating tube fixed to the sleeve, dividing the space between the internal tube and the external mantle into two coaxial annular spaces, communicating near the front face of the nozzle, means for supply and removal of a cooling liquid to and from said annular spaces,
  • the separating tube extending into a distributing insert, leaving a narrow space at places adjacent to the operating surfaces of the nozzle,
  • a distribution chamber arranged axially slidable within the torch head
US00330026A 1972-02-09 1973-02-06 Plasma torch with axial supply of the stabilizing gas Expired - Lifetime US3858072A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CS806A CS163895B1 (de) 1972-02-09 1972-02-09

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Country Status (10)

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US (1) US3858072A (de)
JP (1) JPS4889149A (de)
BE (1) BE795236A (de)
CH (1) CH550528A (de)
CS (1) CS163895B1 (de)
DD (1) DD101585A1 (de)
DE (1) DE2306022C3 (de)
FR (1) FR2171418B1 (de)
GB (1) GB1416783A (de)
SE (1) SE378998B (de)

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3991764A (en) * 1973-11-28 1976-11-16 Purdue Research Foundation Plasma arc scalpel
US4625092A (en) * 1984-11-30 1986-11-25 Plasma Energy Corporation Plasma arc bulk air heating apparatus
US4628177A (en) * 1984-08-10 1986-12-09 B & B Precision Machines, Inc. Arc welding torch
US4645899A (en) * 1984-09-28 1987-02-24 Fried. Krupp Gesellschaft Mit Beschrankter Haftung Plasma torch with hollow fluid cooled nozzle
US4814577A (en) * 1986-06-26 1989-03-21 Cebora S.P.A. Control circuit in plasma arc cutting and welding equipment designed for transferred arc operation
WO2001076328A2 (en) * 2000-03-31 2001-10-11 Thermal Dynamics Corporation Plasma arc torch and method for longer life of plasma arc torch consumable parts
US20020092922A1 (en) * 2001-01-13 2002-07-18 Ronald Steiger Spraying method and a spray system for coating liquids
US20020092923A1 (en) * 2001-01-13 2002-07-18 Ronald Steiger Spraying method and a spray system for coating liquids
US20030213782A1 (en) * 2002-04-19 2003-11-20 Mackenzie Darrin H. Plasma arc torch
WO2004030551A1 (en) * 2002-10-04 2004-04-15 Plasma Surgical Investments Limited Plasma surgical device
US20080217305A1 (en) * 2007-02-16 2008-09-11 Hypertherm, Inc. Gas-Cooled Plasma Arc Cutting Torch
US20100102040A1 (en) * 2005-04-28 2010-04-29 E.E.R. Environmental Energy Resources (Israel) Ltd plasma torch for use in a waste processing chamber
US20110031224A1 (en) * 2009-08-10 2011-02-10 The Esab Group, Inc. Retract start plasma torch with reversible coolant flow
US20150028002A1 (en) * 2013-07-25 2015-01-29 Hypertherm, Inc. Devices for Gas Cooling Plasma Arc Torches and Related Systems and Methods
CN106304599A (zh) * 2016-09-29 2017-01-04 成都真火科技有限公司 一种用于大功率层流电弧等离子体束发生器的密封结构

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1520000A (en) * 1974-10-10 1978-08-02 Vni P Konstr I Tech Plasma arc torches
GB1598574A (en) * 1977-03-30 1981-09-23 Hosoda N Plasma-arc cutting machine
CA1105569A (en) * 1977-10-18 1981-07-21 Ivan A. Kuznetsov Plasma arc torch head
US4430546A (en) * 1981-08-14 1984-02-07 Metco, Inc. Plasma spray gun nozzle
DE3216556A1 (de) * 1982-05-04 1983-11-17 Messer Griesheim Gmbh, 6000 Frankfurt Plasmabrenner, insbesondere plasma-pulver-auftragschweissbrenner
EP0094984A1 (de) * 1982-07-12 1983-11-30 Manfred J. Wallner Lichtbogenschweiss- oder Schneidbrenner
JPS6245530U (de) * 1985-08-29 1987-03-19
US4902871A (en) * 1987-01-30 1990-02-20 Hypertherm, Inc. Apparatus and process for cooling a plasma arc electrode
DE102009006132C5 (de) 2008-10-09 2015-06-03 Kjellberg Finsterwalde Plasma Und Maschinen Gmbh Düse für einen flüssigkeitsgekühlten Plasmabrenner, Düsenkappe für einen flüssigkeitsgekühlten Plasmabrenner sowie Plasmabrennerkopf mit derselben/denselben

Citations (2)

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US3130292A (en) * 1960-12-27 1964-04-21 Union Carbide Corp Arc torch apparatus for use in metal melting furnaces
US3242305A (en) * 1963-07-03 1966-03-22 Union Carbide Corp Pressure retract arc torch

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Publication number Priority date Publication date Assignee Title
NL131703C (de) * 1960-08-01 1900-01-01

Patent Citations (2)

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Publication number Priority date Publication date Assignee Title
US3130292A (en) * 1960-12-27 1964-04-21 Union Carbide Corp Arc torch apparatus for use in metal melting furnaces
US3242305A (en) * 1963-07-03 1966-03-22 Union Carbide Corp Pressure retract arc torch

Cited By (41)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3991764A (en) * 1973-11-28 1976-11-16 Purdue Research Foundation Plasma arc scalpel
US4628177A (en) * 1984-08-10 1986-12-09 B & B Precision Machines, Inc. Arc welding torch
US4645899A (en) * 1984-09-28 1987-02-24 Fried. Krupp Gesellschaft Mit Beschrankter Haftung Plasma torch with hollow fluid cooled nozzle
US4625092A (en) * 1984-11-30 1986-11-25 Plasma Energy Corporation Plasma arc bulk air heating apparatus
US4814577A (en) * 1986-06-26 1989-03-21 Cebora S.P.A. Control circuit in plasma arc cutting and welding equipment designed for transferred arc operation
WO2001076328A3 (en) * 2000-03-31 2002-07-04 Thermal Dynamics Corp Plasma arc torch and method for longer life of plasma arc torch consumable parts
US20030034333A1 (en) * 2000-03-31 2003-02-20 Kevin Horner-Richardson Plasma arc torch and method for improved life of plasma arc torch consumable parts
US20060237399A1 (en) * 2000-03-31 2006-10-26 Horner-Richardson Kevin D Plasma arc torch and method for improved life of plasma arc torch consumable parts
US6987238B2 (en) 2000-03-31 2006-01-17 Thermal Dynamics Corporation Plasma arc torch and method for improved life of plasma arc torch consumable parts
WO2001076328A2 (en) * 2000-03-31 2001-10-11 Thermal Dynamics Corporation Plasma arc torch and method for longer life of plasma arc torch consumable parts
US6857581B2 (en) 2001-01-13 2005-02-22 Itw Oberflachentechnik Gmbh & Co. Kg Spraying method and a spray system for coating liquids
US20020092922A1 (en) * 2001-01-13 2002-07-18 Ronald Steiger Spraying method and a spray system for coating liquids
US20020092923A1 (en) * 2001-01-13 2002-07-18 Ronald Steiger Spraying method and a spray system for coating liquids
US6915963B2 (en) * 2001-01-13 2005-07-12 Itw Oberflachentechnik Gmbh & Co. Kg Spraying method and a spray system for coating liquids
US6946616B2 (en) * 2002-04-19 2005-09-20 Thermal Dynamics Corporation Plasma arc torch cooling system
US7019254B2 (en) 2002-04-19 2006-03-28 Thermal Dynamics Corporation Plasma arc torch
US20040094519A1 (en) * 2002-04-19 2004-05-20 Conway Christopher J. Plasma arc torch electrode
US20030213782A1 (en) * 2002-04-19 2003-11-20 Mackenzie Darrin H. Plasma arc torch
US20040000538A1 (en) * 2002-04-19 2004-01-01 Conway Christopher J. Plasma arc torch tip
US6919526B2 (en) 2002-04-19 2005-07-19 Thermal Dynamics Corporation Plasma arc torch head connections
US20030213784A1 (en) * 2002-04-19 2003-11-20 Mackenzie Darrin H. Plasma arc torch consumables cartridge
US20040079735A1 (en) * 2002-04-19 2004-04-29 Kinerson Kevin J. Plasma arc torch head connections
US20030213783A1 (en) * 2002-04-19 2003-11-20 Kinerson Kevin J. Plasma arc torch cooling system
US6989505B2 (en) 2002-04-19 2006-01-24 Thermal Dynamics Corporation Plasma arc torch consumables cartridge
US6998566B2 (en) 2002-04-19 2006-02-14 Thermal Dynamics Corporation Plasma arc torch electrode
US7005600B2 (en) 2002-04-19 2006-02-28 Thermal Dynamics Corporation Plasma arc torch tip
US20060004354A1 (en) * 2002-10-04 2006-01-05 Nikolay Suslov Plasma surgical device
US7361175B2 (en) 2002-10-04 2008-04-22 Plasma Surgical Investments Limited Plasma surgical device
WO2004030551A1 (en) * 2002-10-04 2004-04-15 Plasma Surgical Investments Limited Plasma surgical device
US8373087B2 (en) * 2005-04-28 2013-02-12 E.E.R. Enviromental Energy Resources (Israel) Ltd. Plasma torch for use in a waste processing chamber
US20100102040A1 (en) * 2005-04-28 2010-04-29 E.E.R. Environmental Energy Resources (Israel) Ltd plasma torch for use in a waste processing chamber
US20080217305A1 (en) * 2007-02-16 2008-09-11 Hypertherm, Inc. Gas-Cooled Plasma Arc Cutting Torch
CN101632328B (zh) * 2007-02-16 2013-04-24 海别得公司 气体冷却的等离子体电弧割炬
US8089025B2 (en) * 2007-02-16 2012-01-03 Hypertherm, Inc. Gas-cooled plasma arc cutting torch
US8258423B2 (en) 2009-08-10 2012-09-04 The Esab Group, Inc. Retract start plasma torch with reversible coolant flow
US20110031224A1 (en) * 2009-08-10 2011-02-10 The Esab Group, Inc. Retract start plasma torch with reversible coolant flow
US8633414B2 (en) 2009-08-10 2014-01-21 The Esab Group, Inc. Retract start plasma torch with reversible coolant flow
US20150028002A1 (en) * 2013-07-25 2015-01-29 Hypertherm, Inc. Devices for Gas Cooling Plasma Arc Torches and Related Systems and Methods
US9144148B2 (en) 2013-07-25 2015-09-22 Hypertherm, Inc. Devices for gas cooling plasma arc torches and related systems and methods
US10716199B2 (en) * 2013-07-25 2020-07-14 Hypertherm, Inc. Devices for gas cooling plasma arc torches and related systems and methods
CN106304599A (zh) * 2016-09-29 2017-01-04 成都真火科技有限公司 一种用于大功率层流电弧等离子体束发生器的密封结构

Also Published As

Publication number Publication date
GB1416783A (en) 1975-12-10
DE2306022C3 (de) 1979-07-19
FR2171418B1 (de) 1979-04-20
CH550528A (de) 1974-06-14
JPS4889149A (de) 1973-11-21
DD101585A1 (de) 1973-11-12
BE795236A (fr) 1973-05-29
DE2306022B2 (de) 1978-11-23
FR2171418A1 (de) 1973-09-21
SE378998B (de) 1975-09-22
DE2306022A1 (de) 1973-08-23
CS163895B1 (de) 1975-11-07

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