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EP0208196A2 - Dispositif de surveillance automatique d'une flamme - Google Patents

Dispositif de surveillance automatique d'une flamme Download PDF

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Publication number
EP0208196A2
EP0208196A2 EP86108632A EP86108632A EP0208196A2 EP 0208196 A2 EP0208196 A2 EP 0208196A2 EP 86108632 A EP86108632 A EP 86108632A EP 86108632 A EP86108632 A EP 86108632A EP 0208196 A2 EP0208196 A2 EP 0208196A2
Authority
EP
European Patent Office
Prior art keywords
flame
cutting
pressure
burner
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.)
Ceased
Application number
EP86108632A
Other languages
German (de)
English (en)
Other versions
EP0208196A3 (fr
Inventor
Georg Roeder
Helmut Sachs
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.)
Messer Griesheim GmbH
Original Assignee
Messer Griesheim GmbH
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 Messer Griesheim GmbH filed Critical Messer Griesheim GmbH
Publication of EP0208196A2 publication Critical patent/EP0208196A2/fr
Publication of EP0208196A3 publication Critical patent/EP0208196A3/fr
Ceased legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/46—Details
    • F23D14/72—Safety devices, e.g. operative in case of failure of gas supply
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/46—Details
    • F23D14/48—Nozzles
    • F23D14/52—Nozzles for torches; for blow-pipes
    • F23D14/54—Nozzles for torches; for blow-pipes for cutting or welding metal

Definitions

  • the invention relates to a method for automatically monitoring a flame according to the preamble of claim 1.
  • the tool in particular the cutting torch, is automatically moved by a preferably numerically controlled flame cutting machine in accordance with a predetermined processing pattern.
  • This automatic burner positioning means shorter set-up times and higher component accuracies.
  • the automatic switching and positioning processes must be monitored in order to guarantee an automatic process on the one hand and on the other hand to reduce the risk of rejects.
  • a method for monitoring flames in particular the flame of a cutting torch, is known, in which the electrical potential difference which forms in the area of the flame or the conductivity of the ionized flame is used for monitoring (Swiss Patent 420,022).
  • the potential difference is detected by probe electrodes arranged in the flame.
  • a device for monitoring a flame cutting process is known from GB-PS 12, 41, 129, with which a cut tear can be detected.
  • a body is attached to the cutting nozzle, in which two channels are provided with outlet bores directed towards the workpiece surface, one channel being connected to a compressed air source and the other measuring channel to pressure switches.
  • the compressed air flow directed at the workpiece surface is set so that no pressure changes occur in the adjacent measuring channel during a continuous flame cut with the heating flame and the cutting oxygen jet.
  • the gases or the flames on the workpiece surface are deflected laterally and influence the compressed air flow. This leads to a change in the pressure in the measuring channel.
  • Such a device only detects changes in the gas or flame during flame cutting with a defined height adjustment of the torch with the measuring device to the workpiece surface. If there is a large distance between the burner and the workpiece, as is specified in particular when the heating flame (fuel gas and heating oxygen) is ignited automatically, no measuring signals can be generated with such a measuring device.
  • the "mobility" of the burner is restricted by the additional arrangement of a housing in which the channels are arranged. Flame cutting within a groove or on a wall of a step-shaped workpiece is only possible to a limited extent. The travel range of the burner is limited by the measuring device. The additional arrangement of the measuring device in the work area increases the risk of collision between the workpieces to be machined and the burner / measuring device combination.
  • the channels In order to ensure a functional operation of the measuring device, the channels must be in the immediate area of the gas streams / flame be arranged. During flame cutting, this leads to cooling of the workpiece surface by the compressed air flowing out and thus to a reduction in the heating power.
  • the opposing heating flame is influenced by the compressed air stream escaping on one side, which can lead to a cut-off in particular when flame cutting with a leading heating flame. In this case, the turbulence of the heating flame or heating flames generated by the compressed air flow leads to a lifting of the heating flame from the outlet side of the burner nozzle.
  • the operating medium compressed air is consumed during the entire on-time of the flame cutting machine by the continuously escaping compressed air flow, which leads to high costs.
  • the additional compressed air lines lead to an increased risk of twisting and twisting of the hose package.
  • the additional measuring device increases the burner weight and thus the masses to be moved during the flame cut.
  • the invention has for its object to avoid the use of additional measurement gases and sensors arranged outside the burner for automatic monitoring of the flame and to provide a device for automatic monitoring of the flame, which is simple and inexpensive to implement and does not interfere with the machining process device geometry leads.
  • the gas supply is automatically interrupted after a preset time if the flame does not come from the monitoring device and, on the other hand, a follow-up sequence on a machine tool after the flame has been generated by the monitoring device , especially flame cutting machine, released.
  • the pressure measurement of flame gases via pressure signal bores or channels arranged in the burner and the supply of the pressure via hoses connected to the channels or bores and the like to the monitoring device avoid collision risks and the device geometry is changed only insignificantly. Due to the arrangement of pressure signal bores, preferably in the heating nozzle, and the transmission of this pressure within the burner via channels, no additional external geometric shapes of the burner need to be taken into account when programming the machining contour. This makes programming easier.
  • the combustion pressure present after the ignition and formation of the flame is measured and, in the event of sudden pressure changes, the gas supply and preferably the subsequent process are switched off immediately.
  • the displacement of the combustion of the heating gases from the nozzle face into the inside of the cutting torch produces a change in the pressure state at the measuring point from an overpressure to a 'lower pressure level.
  • This pressure drop generates a signal with which the magnetic valves of the heating gases close for the cutting torch affected by the kickback.
  • the cutting torch is advantageously protected from burning out and thus from being destroyed.
  • the advantages achieved by the invention are that, preferably after ignition, a signal is available which reports the formation of the flame, regardless of the distance between the torch and the workpiece and without the use of additional measurement gases.
  • the outer and inner torch geometry does not affect the machining process, nor does it affect programming and process-related impairments, such as impairments to the torch guidance.
  • the method is particularly advantageous for flame cutting workpieces with a cutting torch which is moved by a numerically controlled flame cutting machine. Can with such a method on the monitoring of flashbacks If the cutting torch is dispensed with due to other safety devices or measures, an advantageous device for carrying out the method according to the invention is the detection of the pressure in the cutting oxygen channel. Additional pressure signal holes may be allotted and it must only for a barrier between the monitor and the S chneidsauerstoffkanal taken during the burning section preparedness will be.
  • FIG. 1 shows an overview circuit diagram of the gas flame monitoring device in a schematic simplified illustration
  • Fig. 2 shows a section A of Fig. 1 in a half-sectional view.
  • Fig. 1 the cutting torch with 10, the flame cutting nozzle with 11, the fuel gas line with 12, the cutting oxygen line with 13 and the heating oxygen line with 14.
  • the lines 12, 13, 14 are connected to the cutting torch 10 via the torch connections 15, 16, 17 and to the supply sources for fuel gas, cutting oxygen and heating oxygen, not shown, via hose connections, not shown.
  • Shut-off devices 18, 19, 20, which are preferably designed as solenoid valves, are preferably arranged in lines 12, 13, 14 in front of the gas quantity controls, which are not shown in detail.
  • the windings of the control magnets 25, 26, 27 are connected via control lines 21, 22, 23 to a controller 24, preferably an NC flame cutting machine controller.
  • the cutting torch 10 consists essentially of the valve body 28 with the torch connections 15, 16, 17, the torch head 29 and the valve body and torch head connecting guide tube 30.
  • An injector not shown, is arranged in the valve body 28 and is connected on the inflow side to the fuel gas and heating oxygen line and on the outflow side to the heating gas supply tube, not shown.
  • Heating gas is understood as a mixture of fuel gas and heating oxygen.
  • the heating gas supply pipe is connected to the burner head 29 on the outflow side.
  • a heating gas bore 31 (FIG. 2) is provided in the burner head 29, which is connected to the heating gas supply pipe and opens into an annular space 32.
  • the annular space 32 is connected to the annular heating channel 33 of the cutting nozzle 11.
  • a cutting oxygen tube is connected to a cutting oxygen bore 34 arranged in the torch head 29 via the burner connection 16 for cutting oxygen and bores arranged in the valve body 28.
  • the cutting oxygen bore 34 is connected to the cutting oxygen channel 35 of the cutting nozzle 11.
  • the flame cutting nozzle 11 is preferably designed as a two-part nozzle.
  • the cutting nozzle 36 contains the cutting oxygen channel 35 and the heating slots 37 for the supply of the heating gas.
  • the heating nozzle 38 surrounds the cutting nozzle 36, so that the annular heating channel 33 is formed by the outer contour of the cutting nozzle and the inner contour of the heating nozzle and the heating slots 37 are sealed off from the outside.
  • the cutting nozzle 36 is preferably set back relative to the heating nozzle 38, regardless of the fuel gas (slow or fast. Burning fuel gas). Due to the recessed arrangement of the cutting nozzle 36, a cylindrical measuring space 40 is formed between the front side 39 of the heating nozzle and the front side 41 of the cutting nozzle 36. In the measuring space 40, a larger-diameter annular groove 42 is provided in the heating nozzle 38, into which a pressure signal bore 43 provided in the heating nozzle 38 opens.
  • the cutting nozzle 36 and the heating nozzle 38 are connected to the torch head 29 by means of threaded connections 44, 45.
  • the burner head 29 has at its end facing the nozzle 11 an annular groove 46, in the outer wall 47 of which the heating nozzle 38 is screwed.
  • In the circular center pin 48 of the burner head 29 is one with the Cutting oxygen bore 34 connected larger bore 49 is provided, in which the cutting nozzle 36 is screwed.
  • the bore 49 and the outer wall 47 are formed as a conical seat 50, 51 at their end facing the nozzle 36, 38.
  • Correspondingly shaped conical surfaces 52, 53 are provided on the circumference of the cutting nozzle 36 and the heating nozzle 38, which bear against the conical seats 50, 51 of the torch head 29 after the nozzles 36, 38 have been screwed in.
  • an annular groove 54 provided 55th
  • the pressure signal bore 43 arranged in the heating nozzle 38 opens into an annular gap 56 formed on the conical surface 53, via which the pressure signal bore 43 is connected to a pressure signal duct 57 arranged in the burner head 29.
  • two pressure signal bores 43 are arranged in the heating nozzle, which open into the annular gap 56.
  • the pressure signal channel 57 is connected to the valve body 28 via pressure signal lines 58 (FIG. 1). Pressure bores, not shown, are provided in the valve body 28, to which an angled connection 59 with a flame arrester 60 is connected.
  • the flame arrester 60 is connected via a measuring hose 61 to a pressure evaluation unit 62, preferably a membrane switch, which is coupled to the controller 24 via a signal line 63.
  • the controller 24 is also connected via a control line 64 to an ignition device 65 which automatically ignites the heating gas via an ignition burner arranged outside or preferably via an ignition wire arranged inside the cutting oxygen channel.
  • the cutting oxygen channel is connected to the heating gas channel via a transverse bore in the preferably used internal ignition.
  • the ignition device 65 After a predetermined period of time, preferably less than 500 milliseconds after opening the shut-off elements 18, 20 after which an escape of the heating gases from the flame cutting nozzle 11 is ensured, the ignition device 65 is automatically switched by the controller 24 via the control line 64. The ignition device 65 generates an ignition flame outside the cutting torch 10, but in the vicinity of the flowing heating gases.
  • the ignition device 65 preferably generates an ignition spark in the cutting oxygen bore 34 via an ignition wire (not shown).
  • the cutting oxygen hole is connected to the heating gas hole via a connecting channel, so that a part of this heating gas is in the flowing heating gas Cutting oxygen bore 34 accumulates and can be ignited by means of a spark.
  • a timer is advantageously arranged within the ignition device 65 or within the controller 24, by means of which the ignition is repeated over a predetermined period of time.
  • the pressure difference which now arises in the measuring chamber 40 is conducted via the annular groove 42 arranged in the measuring chamber and at least one pressure signal bore 43 to the annular gap 56 and via the pressure signal channel 57 the pressure signal line 58, the bore arranged in the valve body, the angle connection 59 with the Flame barrier 60 and the measuring hose 61 of the pressure evaluation unit 62 supplied.
  • This measuring signal overpressure compared to atmospheric pressure causes a potential-free changeover contact of the membrane switch 62 to change its contact position and only return to the starting position (starting position - atmospheric pressure) when the heating gases are no longer burning.
  • the electrical signal generated by the change in the contact position of the changeover contact is supplied to the controller 24 via the signal line 63 and releases the subsequent sequence.
  • the signal can be used to switch a timer which, after a preset period of time, opens the shut-off element 19 via the control line 22 and thus releases the cutting oxygen supply.
  • the pressure increase occurring in the measuring space 40 due to the volume expansion of the heating gases is essentially formed by non-burning gases of the heating flame 69 (flame cone and auxiliary flame). Since these unburned gases, which are split off from the heating gas, are conducted into the pressure signal bore via the annular groove 42, the angle connection 59 is provided with a flame arrester 60, which advantageously damages the pressure evaluation unit prevented in the case of flames migrating into the pressure sign bore.
  • the measurement signal can also be fed to a PE pressure evaluation unit, which transmits the membrane movement caused by the measurement signal pressure, for example to the wiper of a potentiometer, and thus continuously converts the measurement signal pressure into an electrical signal that continuously changes an electrical quantity as the measurement signal pressure increases.
  • a PE pressure evaluation unit which transmits the membrane movement caused by the measurement signal pressure, for example to the wiper of a potentiometer, and thus continuously converts the measurement signal pressure into an electrical signal that continuously changes an electrical quantity as the measurement signal pressure increases.
  • Inductive, capacitive or resistance changes for example, can be generated as signal quantities as electrical quantities. It is also possible to switch phototransistors or optical control elements.
  • the changeover contact of the membrane switch is switched during the entire flame cutting period of the cutting torch. If, for example, a flame flashback occurs in the cutting torch 10 during the flame cutting process, the combustion of the heating gas shifts from the nozzle face 41, 39 into the interior of the cutting torch 10, up to the vicinity of the injector. As a result, a change in the measurement pressure state in the measurement space 40 from an overpressure to atmospheric pressure is generated. This pressure drop leads to the switching of the changeover contact of the membrane switch in its rest position. In this case, a control signal is generated in the pressure evaluation unit 62, which is preferably fed to the control via which the shut-off devices 18, 19, 20 are closed. Of course, it is also possible to control the shut-off devices 18, 19, 20 directly with this control signal.
  • the measurement signal pressure is received in the pressure signal bore 43 and fed to the pressure evaluation unit 62 via channels and lines
  • the pressure is absorbed in the cutting oxygen channel and via the cutting oxygen bore and the like S supplied chneidsauerstoffzu operationsrohr a Druckauswertü.
  • a decoupling of Druckauswertü must be chneidsauerstoff in pouring south.
  • a flashover into the cutting torch cannot be monitored. It is advantageous, however, in this embodiment no additional heating nozzle disposed in the bore D jerk signal required, which leads to simplify the fabrication and nozzles to further reduce the manufacturing costs.
  • gas flame monitoring described above in an exemplary embodiment can be used particularly advantageously in automatic flame cutting with an NC-controlled flame cutting machine, by which the cutting torch 10 is moved according to a predetermined path.
  • gas flame monitoring can also be used to advantage when welding.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
  • Regulation And Control Of Combustion (AREA)
EP86108632A 1985-07-11 1986-06-25 Dispositif de surveillance automatique d'une flamme Ceased EP0208196A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19853524773 DE3524773A1 (de) 1985-07-11 1985-07-11 Verfahren zum automatischen rberwachen einer flamme
DE3524773 1985-07-11

Publications (2)

Publication Number Publication Date
EP0208196A2 true EP0208196A2 (fr) 1987-01-14
EP0208196A3 EP0208196A3 (fr) 1988-10-12

Family

ID=6275503

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86108632A Ceased EP0208196A3 (fr) 1985-07-11 1986-06-25 Dispositif de surveillance automatique d'une flamme

Country Status (2)

Country Link
EP (1) EP0208196A3 (fr)
DE (1) DE3524773A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5344313A (en) * 1993-04-30 1994-09-06 Chevron Research And Technology Company Fugitive volatile organic compound vapor collection system
US5451140A (en) * 1993-04-30 1995-09-19 Chevron U.S.A. Inc. Fugitive volatile organic compound vapor collection system
AU665307B2 (en) * 1993-06-02 1995-12-21 Johnson Service Company Intelligent transient eliminator for an ignition system
EP0656509A4 (fr) * 1993-05-21 1996-11-04 Tatarskoe Proizv Ob Energetiki Dispositif de regulation d'une flamme.
EP2136140A1 (fr) * 2008-06-20 2009-12-23 Linde AG Tête de brûleur pour brûleurs guidés manuellement ou à l'aide de machines
WO2018035965A1 (fr) * 2016-08-26 2018-03-01 江苏亚威机床股份有限公司 Buse de coupe composite pour perforation à air ayant deux canaux d'air reliés en parallèle

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62288407A (ja) * 1986-06-04 1987-12-15 Souji Kobayashi 溶断機
DE4228948A1 (de) * 1992-08-31 1994-03-10 Friedrich Dipl Ing Bartels Verfahren und Vorrichtung zur Flammenüberwachung
DE102014117756A1 (de) 2014-12-03 2016-06-09 Messer Cutting Systems Gmbh Sicherheitseinrichtung zum Einbau in die Gasversorgungsinstallation eines Brenners für die thermische Materialbearbeitung
FR3107849B1 (fr) * 2020-03-09 2023-03-10 Soudo Service Buse pour chalumeau d’oxycoupage refroidi par un liquide.

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1220356B (de) * 1963-09-14 1966-07-07 Messer Griesheim Gmbh Verfahren zur UEberwachung und Regelung von Flammen vorzugsweise gasfoermiger oder fluessiger Brennstoffe oder deren Wirkung
DE1729900A1 (de) * 1968-03-08 1971-07-29 Messer Griesheim Gmbh Verfahren zum Verhindern der Zerstoerung von Autogenbrennern durch Rueckzuendung und Vorrichtung zur Durchfuehrung des Verfahrens
GB1241129A (en) * 1969-03-25 1971-07-28 Koike Sanso Kogyo Company Ltd Method of and apparatus for detecting a condition incapable of cutting in gas cutting operations

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5344313A (en) * 1993-04-30 1994-09-06 Chevron Research And Technology Company Fugitive volatile organic compound vapor collection system
US5451140A (en) * 1993-04-30 1995-09-19 Chevron U.S.A. Inc. Fugitive volatile organic compound vapor collection system
EP0656509A4 (fr) * 1993-05-21 1996-11-04 Tatarskoe Proizv Ob Energetiki Dispositif de regulation d'une flamme.
AU665307B2 (en) * 1993-06-02 1995-12-21 Johnson Service Company Intelligent transient eliminator for an ignition system
EP2136140A1 (fr) * 2008-06-20 2009-12-23 Linde AG Tête de brûleur pour brûleurs guidés manuellement ou à l'aide de machines
WO2018035965A1 (fr) * 2016-08-26 2018-03-01 江苏亚威机床股份有限公司 Buse de coupe composite pour perforation à air ayant deux canaux d'air reliés en parallèle

Also Published As

Publication number Publication date
DE3524773A1 (de) 1987-01-22
EP0208196A3 (fr) 1988-10-12

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