US3825718A - Plasmatron - Google Patents

Plasmatron Download PDF

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Publication number
US3825718A
US3825718A US00205975A US20597571A US3825718A US 3825718 A US3825718 A US 3825718A US 00205975 A US00205975 A US 00205975A US 20597571 A US20597571 A US 20597571A US 3825718 A US3825718 A US 3825718A
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United States
Prior art keywords
arc
nozzles
nozzle
plasmatron
cathode
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Expired - Lifetime
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US00205975A
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I Navdarashvili
M Devdariani
O Mosiashvili
R Suladze
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Priority to US00205975A priority Critical patent/US3825718A/en
Priority to DE2162781A priority patent/DE2162781A1/en
Priority to FR7146632A priority patent/FR2165302A5/fr
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Publication of US3825718A publication Critical patent/US3825718A/en
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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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K10/00—Welding or cutting by means of a plasma
    • 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
    • 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
    • H05H1/3452—Supplementary electrodes between cathode and anode, e.g. cascade
    • 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
    • H05H1/3468—Vortex generators

Definitions

  • a consumable cathode plasma arc torch for workmg PP 205,975 metals with a water-stabilized plasma are in which a 1 tubular nozzle is mounted in co-axial relationship to 152 ms. c1 219/121 P, 219/75 the cathode with the lateral Surface there [511 1m.
  • Such plasmatrons have a consumable cylindrical cathode whose active section extends inside the tubular nozzle communicating with a cooling liquid supply chamber.
  • the liquid supply channels ensure tangential delivery of the water into the chamber and tubular nozzle.
  • the inner and other nozzles are installed in tandem before the'active end of the cathode.
  • a chamber formed between the'walls of these nozzles serves for the delivery of water which stablizes the plasma arc.
  • the tubular nozzle is arranged so that the surface of its lower-end is somewhat higher than the end of the inner nozzle facing the cathode.
  • a part of the cooling water passes in a turbulent flow through the tubular nozzle and enters the inner nozzle and then the water collector.
  • part of the cooling water gets into the orifices of the arc-forming nozzles which cools down the arc and impairs the stability of its burning.
  • such an arrangementof the nozzles increases the distance between the working end of the cathode and the inner arc-forming nozzle, thereby reducing the efficient length of the plasma flame. All these factors reduce the reliability and efficiency of the plasmatron.
  • An object of the present invention lies in improving the reliability and efficiency of the plasmatron.
  • the invention aims at arranging the tubularand arcforming nozzles in such a manner as to decrease considerably the possibility of the cooling liquid getting into the orifices of the arc-forming nozzles and to provide conditions for decreasing the distance between the lower end of the cathode and the inner arc-forming nozzle.
  • a plasmatron for working metals. with a water-stabilized plasma are comprising a cathode, a tubular nozzle and two arc-forming nozzles, the inner and outer ones,-in which, according to the invention, the section of the tubular nozzle facing the inner nozzle is located in the space of the latter.
  • the end of the tubular nozzle can be installed flush with the surface of the end of the inner nozzle which faces the end of the cathode or enters the inner nozzle.
  • FIG. 1 illustrates a part of the plasmatron wherein the tubular nozzle is installed flush with the surface of the inner nozzle facing the end of the cathode;
  • FIG. 2 is another relative arrangement of the inner and tubular nozzles
  • FIG. 3 is a section takes along line III-III of FIG. 1.
  • a consumable graphite cathode 1 is installed in a body 2 whose wall is provided with a tangential channel 3 for the delivery of cooling liquid, e.g. water, into a chamber 4 formed by 1 2 v the wall of the body 2 and cathode l. Closely adjoining this chamber 4 is a tubular nozzle 5 whose space communicates with said chamber 4. The active section of the cathode 1 passes through this nozzle.
  • cooling liquid e.g. water
  • the tubular nozzle 5 has a rounded section at the point where the inner wall merges into the end portion.
  • arc-forming nozzles 6 and 7 Mounted in tandem, one after the other, before the end of the cathode, are two arc-forming nozzles 6 and 7, inner and outer ones, respectively. These nozzles deliver water which stabilizes the plasma arc.
  • a chamber 8 closed at the sides by the projections of a part 9 which strengthens the arc-forming nozzles and is fastened to the body 1.
  • the walls of the part 9 are provided with tangential channels 10 (see also FIG. 3) through which stabilizing water is delivered into the chamber at a pressure of l 2 atm.
  • the section of the tubular nozzle 5 facing the inner nozzle 6 should be within the space of the latter.
  • the end of the nozzle 5 is installed flush with the outer surface of the inner nozzle.
  • a circular gap 11 formed by such an installation communicates the nozzle 6 with the water collector, the water from which is discharged outside through a channel 13.
  • the tubular nozzle 5 can be installed with its end entering the nozzle 6 (as shownin FIG. 2).
  • the cooling liquid is also discharged through the circular gap 11.
  • the size of this gap depends on the velocity of the cooling liquid flowing out of the tubular nozzle 5 and ranges from 2 to 5 mm to obtain the best results when the'water is delivered at a pressure of 3 to 4 atm.
  • the plasmatron functions as follows.
  • the chambers 4 and 8 are filled with stabilizing and cooling liquids, respectively. Then an arc is excited between the cathode l and a work (not shown in the drawings) by any known method.
  • the cooling water delivered tangentially into the chamber 4 forms a turbulent stream washing the electrode 1 for cooling it.
  • the'water spreads over the shaped part of the tubular nozzle 5 passes into the circular gap 11 and into the water collector '12 it is discharged outside.
  • the water stabilizing the plasma arc is delivered tangentially into the chamber 8, is swirled there and passes in the form of a thin film through the orifices of the nozzles '6 and 7. Part of this water turns into steam which, dissociating and ionizing, contributes to the formation of plasma.
  • stabilized plasma arc comprising a consumable cath-.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Mechanical Engineering (AREA)
  • Plasma Technology (AREA)

Abstract

A consumable cathode plasma arc torch for working metals with a water-stabilized plasma arc in which a tubular nozzle is mounted in co-axial relationship to the cathode with the lower lateral surface thereof in coplanar relationship with an upper lateral surface of one of two tandenly mounted arc forming nozzles. This relationship increases the reliability and efficiency of the plasma arc torch by decreasing the possibility of cooling liquid getting into the arc-forming nozzles and by decreasing the distance between the lower end of the cathode and the inner arcforming nozzle.

Description

. 3 718 v YDZEPIIA OR 398259 "umtecl states Patent 91 z I v 1111- 3,825,718 Mosiash'vili et al. Y July 23, 1974 [54] PLASMATRON 3,567,898 3 1971 Fein 219/121 P [76] Inventors: OtariYakovlevi'ch Mosiashvili,ulitsa zfg f g g 512 31 3 Perovskoi, 15; Robert Nikolaevich Suladze, ulitsa Barnova, 1 12; Ivan lsidorovich Navdarashvili, ulitsa lmgvsky Tupik l4; Mikhail Georgievich Devdariani, 4 Barnova, 20, all of Tbilisi, U.S.S.R.
Primary ExaminerJ. V. Truhe Assistant ExaminerG. R. Peterson I Attorney, Agent, or Firm-Eric H. Waters [22] Filed: Dec. 8, 1971 [57] ABSTRACT I I Y A consumable cathode plasma arc torch for workmg PP 205,975 metals with a water-stabilized plasma are in which a 1 tubular nozzle is mounted in co-axial relationship to 152 ms. c1 219/121 P, 219/75 the cathode with the lateral Surface there [511 1m. 01 B23k 9/00 coplanar re-lamnship with an upper lateral Surface 58 Field of Search 219/121 P,'74, 75, 76, Of andenly mounted arc forming nozzles- 219/130 This relationship increases the reliability and efficiency of the plasma arc torch by decreasing the possi- [56] Reterences Cited bility of cooling liquid getting into the arc-forming nozzles and by decreasing the distance between the UNITED STATES PATENTS lower end of the cathode and the inner arc-forming 3,097,292 7/1963 Kugler et al ...219/1211P z 3,344,256 9/1967 Anderson .4219/1211 3,553,422 1/1971 McCoy 219 121 P r 3 Claims, 3' Drawing Figures 1 PLASMATRON The present invention relates to an improvement in plasmatrons and, more particularly, in the plasmatrons used for working metals with a water-stabilized plasma arc, and can be utilized for cutting, welding, depositing of metals and dressing of the finished articles.
Widely known in the art are various types of plasmatrons with a water-stabilized arc. Such plasmatrons have a consumable cylindrical cathode whose active section extends inside the tubular nozzle communicating with a cooling liquid supply chamber. The liquid supply channels ensure tangential delivery of the water into the chamber and tubular nozzle.
The inner and other nozzles are installed in tandem before the'active end of the cathode.
A chamber formed between the'walls of these nozzles serves for the delivery of water which stablizes the plasma arc.
The tubular nozzle is arranged so that the surface of its lower-end is somewhat higher than the end of the inner nozzle facing the cathode. In such a relativearrangement of the nozzles a part of the cooling water passes in a turbulent flow through the tubular nozzle and enters the inner nozzle and then the water collector. However, part of the cooling water gets into the orifices of the arc-forming nozzles which cools down the arc and impairs the stability of its burning. Besides, such an arrangementof the nozzles increases the distance between the working end of the cathode and the inner arc-forming nozzle, thereby reducing the efficient length of the plasma flame. All these factors reduce the reliability and efficiency of the plasmatron.
An object of the present invention lies in improving the reliability and efficiency of the plasmatron.
The invention aims at arranging the tubularand arcforming nozzles in such a manner as to decrease considerably the possibility of the cooling liquid getting into the orifices of the arc-forming nozzles and to provide conditions for decreasing the distance between the lower end of the cathode and the inner arc-forming nozzle. 1 I
This aim is achieved. by providing a plasmatron for working metals. with a water-stabilized plasma are comprising a cathode, a tubular nozzle and two arc-forming nozzles, the inner and outer ones,-in which, according to the invention, the section of the tubular nozzle facing the inner nozzle is located in the space of the latter.
The end of the tubular nozzle can be installed flush with the surface of the end of the inner nozzle which faces the end of the cathode or enters the inner nozzle.
Now the invention will be described in detail by way of examples with reference to the accompanying drawings in which:
FIG. 1 illustrates a part of the plasmatron wherein the tubular nozzle is installed flush with the surface of the inner nozzle facing the end of the cathode;
FIG. 2 is another relative arrangement of the inner and tubular nozzles;
FIG. 3 is a section takes along line III-III of FIG. 1.
In the metal-cutting plasmatron a consumable graphite cathode 1 is installed in a body 2 whose wall is provided with a tangential channel 3 for the delivery of cooling liquid, e.g. water, into a chamber 4 formed by 1 2 v the wall of the body 2 and cathode l. Closely adjoining this chamber 4 is a tubular nozzle 5 whose space communicates with said chamber 4. The active section of the cathode 1 passes through this nozzle.
The tubular nozzle 5 has a rounded section at the point where the inner wall merges into the end portion.
Mounted in tandem, one after the other, before the end of the cathode, are two arc-forming nozzles 6 and 7, inner and outer ones, respectively. These nozzles deliver water which stabilizes the plasma arc.
Between these nozzles there is a chamber 8 closed at the sides by the projections of a part 9 which strengthens the arc-forming nozzles and is fastened to the body 1. The walls of the part 9 are provided with tangential channels 10 (see also FIG. 3) through which stabilizing water is delivered into the chamber at a pressure of l 2 atm.
The section of the tubular nozzle 5 facing the inner nozzle 6 should be within the space of the latter.
As can be seen in FIG. 1, the end of the nozzle 5 is installed flush with the outer surface of the inner nozzle. A circular gap 11 formed by such an installation communicates the nozzle 6 with the water collector, the water from which is discharged outside through a channel 13.
The tubular nozzle 5 can be installed with its end entering the nozzle 6 (as shownin FIG. 2).
In this case the cooling liquid is also discharged through the circular gap 11. The size of this gap depends on the velocity of the cooling liquid flowing out of the tubular nozzle 5 and ranges from 2 to 5 mm to obtain the best results when the'water is delivered at a pressure of 3 to 4 atm.
The plasmatron functions as follows.
The chambers 4 and 8 are filled with stabilizing and cooling liquids, respectively. Then an arc is excited between the cathode l and a work (not shown in the drawings) by any known method.
The cooling water delivered tangentially into the chamber 4 forms a turbulent stream washing the electrode 1 for cooling it. Acted upon by the centrifugal forces, the'water spreads over the shaped part of the tubular nozzle 5, passes into the circular gap 11 and into the water collector '12 it is discharged outside.
The water stabilizing the plasma arc is delivered tangentially into the chamber 8, is swirled there and passes in the form of a thin film through the orifices of the nozzles '6 and 7. Part of this water turns into steam which, dissociating and ionizing, contributes to the formation of plasma.
stabilized plasma arc, comprising a consumable cath-.
ode; two arc-forming nozzles, a first one of said nozzles axially inside the plasmatron being positioned in front of the consumable end of said cathode and a second of said nozzles being spaced downstream of the first, adjacent the axial end of the plasmatron; means for delivering water intermediate said nozzles to stabilize the plasma arc; and a tubular nozzle surrounding said consumable end and having a laterally extending channel co-axial with said consumable end for tangential delivlower end surface of the tubular nozzle terminates so as to be coplanar with the upper lateral surface of said first arc-forming nozzle.
3. A plasmatron according to claim 1 wherein said lower end surface of the tubular nozzle extends into said first arc-forming nozzle.

Claims (3)

1. A plasmatron for working metals with a water-stabilized plasma arc, comprising a consumable cathode; two arc-forming nozzles, a first one of said nozzles axially inside the plasmatron being positioned in front of the consumable end of said cathode and a second of said nozzles being spaced downstream of the first, adjacent the axial end of the plasmatron; means for delivering water intermediate said nozzles to stabilize the plasma arc; and a tubular nozzle surrounding said consumable end and having a laterally extending channel co-axial with said consumable end for tangential delivery into it of a cooling liquid, said tubular nozzle having a lower end surface thereOf being in at least axially coplanar relationship with an upper lateral surface plane of the first one of said arc-forming nozzles so as to form an annular passageway therebetween for egress of said plasma arc-stabilizing water.
2. A plasmatron according to claim 1 wherein said lower end surface of the tubular nozzle terminates so as to be coplanar with the upper lateral surface of said first arc-forming nozzle.
3. A plasmatron according to claim 1 wherein said lower end surface of the tubular nozzle extends into said first arc-forming nozzle.
US00205975A 1971-12-08 1971-12-08 Plasmatron Expired - Lifetime US3825718A (en)

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Application Number Priority Date Filing Date Title
US00205975A US3825718A (en) 1971-12-08 1971-12-08 Plasmatron
DE2162781A DE2162781A1 (en) 1971-12-08 1971-12-17 PLASMA BURNER
FR7146632A FR2165302A5 (en) 1971-12-08 1971-12-24

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3032335A1 (en) * 1979-08-28 1981-03-12 Union Carbide Corp., 10017 New York, N.Y. PLASMA TORCH.
US4570048A (en) * 1984-06-29 1986-02-11 Plasma Materials, Inc. Plasma jet torch having gas vortex in its nozzle for arc constriction
US4954688A (en) * 1989-11-01 1990-09-04 Esab Welding Products, Inc. Plasma arc cutting torch having extended lower nozzle member
US5214264A (en) * 1991-01-30 1993-05-25 Plasma Energy Corporation Plasma torch front electrode
US5416296A (en) * 1994-03-11 1995-05-16 American Torch Tip Company Electrode for plasma arc torch
US20070108165A1 (en) * 2005-11-17 2007-05-17 Petrik Viktor I Configurations and methods for improved plasma torch

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DD151249A1 (en) * 1979-12-18 1981-10-08 Armin Gruenler DUESE FOR A HIGH-POWER PLASMATRON

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3097292A (en) * 1959-11-14 1963-07-09 Kralovopolska Slrojirna Zd Y C Method and apparatus for the maintenance of the arc column in the core of a liquid vortex
US3344256A (en) * 1967-09-26 Method for producing arcs
US3553422A (en) * 1969-04-28 1971-01-05 Air Prod & Chem Plasma arc welding method and apparatus
US3567898A (en) * 1968-07-01 1971-03-02 Crucible Inc Plasma arc cutting torch
US3575568A (en) * 1967-06-08 1971-04-20 Rikagaku Kenkyusho Arc torch
US3641308A (en) * 1970-06-29 1972-02-08 Chemetron Corp Plasma arc torch having liquid laminar flow jet for arc constriction

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3344256A (en) * 1967-09-26 Method for producing arcs
US3097292A (en) * 1959-11-14 1963-07-09 Kralovopolska Slrojirna Zd Y C Method and apparatus for the maintenance of the arc column in the core of a liquid vortex
US3575568A (en) * 1967-06-08 1971-04-20 Rikagaku Kenkyusho Arc torch
US3567898A (en) * 1968-07-01 1971-03-02 Crucible Inc Plasma arc cutting torch
US3553422A (en) * 1969-04-28 1971-01-05 Air Prod & Chem Plasma arc welding method and apparatus
US3641308A (en) * 1970-06-29 1972-02-08 Chemetron Corp Plasma arc torch having liquid laminar flow jet for arc constriction

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3032335A1 (en) * 1979-08-28 1981-03-12 Union Carbide Corp., 10017 New York, N.Y. PLASMA TORCH.
US4311897A (en) * 1979-08-28 1982-01-19 Union Carbide Corporation Plasma arc torch and nozzle assembly
US4570048A (en) * 1984-06-29 1986-02-11 Plasma Materials, Inc. Plasma jet torch having gas vortex in its nozzle for arc constriction
US4954688A (en) * 1989-11-01 1990-09-04 Esab Welding Products, Inc. Plasma arc cutting torch having extended lower nozzle member
EP0426289A2 (en) * 1989-11-01 1991-05-08 ESAB Welding Products, Inc. Plasma ARC cutting torch having extended lower nozzle member
EP0426289A3 (en) * 1989-11-01 1991-12-04 Esab Welding Products, Inc. Plasma arc cutting torch having extended lower nozzle member
US5214264A (en) * 1991-01-30 1993-05-25 Plasma Energy Corporation Plasma torch front electrode
US5416296A (en) * 1994-03-11 1995-05-16 American Torch Tip Company Electrode for plasma arc torch
US20070108165A1 (en) * 2005-11-17 2007-05-17 Petrik Viktor I Configurations and methods for improved plasma torch

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Publication number Publication date
DE2162781A1 (en) 1973-06-28
FR2165302A5 (en) 1973-08-03

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