EP0082078B1 - Elément réfractaire perméable pour l'introduction d'un fluide de brassage dans un bain de métal en fusion - Google Patents

Elément réfractaire perméable pour l'introduction d'un fluide de brassage dans un bain de métal en fusion Download PDF

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Publication number
EP0082078B1
EP0082078B1 EP82402268A EP82402268A EP0082078B1 EP 0082078 B1 EP0082078 B1 EP 0082078B1 EP 82402268 A EP82402268 A EP 82402268A EP 82402268 A EP82402268 A EP 82402268A EP 0082078 B1 EP0082078 B1 EP 0082078B1
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EP
European Patent Office
Prior art keywords
refractory
stirring
fluid
permeable
electric circuit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP82402268A
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German (de)
English (en)
French (fr)
Other versions
EP0082078A1 (fr
Inventor
Jean-Claude Grosjean
Jean-Marie Augeard
Eric Lienaux
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.)
Institut de Recherches de la Siderurgie Francaise IRSID
Original Assignee
Institut de Recherches de la Siderurgie Francaise IRSID
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Publication date
Application filed by Institut de Recherches de la Siderurgie Francaise IRSID filed Critical Institut de Recherches de la Siderurgie Francaise IRSID
Priority to AT82402268T priority Critical patent/ATE14751T1/de
Publication of EP0082078A1 publication Critical patent/EP0082078A1/fr
Application granted granted Critical
Publication of EP0082078B1 publication Critical patent/EP0082078B1/fr
Expired legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/48—Bottoms or tuyéres of converters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D1/00—Treatment of fused masses in the ladle or the supply runners before casting
    • B22D1/002—Treatment with gases
    • B22D1/005—Injection assemblies therefor

Definitions

  • the present invention relates to the production of metals, in particular steel. It relates more specifically to permeable refractory elements which, implanted on the wall (generally the bottom) of a metallurgical container, are used for the introduction of a stirring fluid, usually an inert gas, into the bath of molten metal contained in this container.
  • a stirring fluid usually an inert gas
  • the permeable refractory elements used schematically have a main permeable part made of refractory material (Magnesia, Dolomite, etc.) taken in a thin metal envelope, the assembly being substantially of the same shape and size as the usual refractory bricks which it replaces.
  • the envelope leaves free the blowing face located in the plane of the surface of the refractory lining lining the interior of the refining container, while the base of the envelope covering the opposite face is provided with a tube for the arrival of the brewing fluid.
  • the object of the present invention is to warn the user of the presence of molten metal against the blowing face of the permeable refractory elements.
  • Another aim is to inform it of the degree of wear of these elements, (and consequently of the whole of the refractory lining), to allow it to intervene, for example by repairing the bottom, when the residual thickness reaches the minimum acceptable.
  • the invention relates to a permeable refractory element for the introduction of a stirring fluid into a bath of molten metal.
  • the element has a free face for the outlet of the stirring fluid and is characterized in that it is provided with at least two electrically conductive bodies, insulated from one another, arranged according to the thickness of the element and one end of which is flush said free face, the other end being connected to an output of an electrical supply so as to constitute the live terminals, of opposite polarities, of an electrical circuit, said circuit comprising means for signaling the "open" state or closed from the circuit.
  • the invention therefore consists in equipping a permeable refractory element with a system for detecting the presence of molten metal using the electroconductive properties of the latter.
  • the terminals are metal rods passing longitudinally through the refractory part of the element.
  • the refractory element is placed in a metal envelope leaving the blowing face free, said envelope constituting one of the electrical terminals.
  • At least one electrical terminal is constituted by a plurality of metal bodies, such as rods, arranged longitudinally in the refractory part of the element and the ends of which are located at levels offset according to the thickness of the element from the blowing face in new condition.
  • the ends of the different bodies are exposed successively as the refractory wear and, by detecting the passage of current in each body, we follow the evolution of wear.
  • Figures 2a, 3a and 2b, 2c are representations similar to those of Figure 1a and Figure 1b respectively, relating to two other alternative embodiments.
  • the permeable refractory elements 1, described here are shown in new condition and have a general shape in the form of a pyramid trunk with a rectangular base in order to be able to replace the usual bricks from the bottom of a refining container.
  • Figures 1a, 2a and 3a also represent an element located in such a background, of which there are 2 in the metal shell outer, in 3 the refractory layer called "safety and in 4 the layer called" wear also in refractory material (bricks).
  • the element 1 essentially consists of a main permeable part 5 made of refractory material, taken in a metal casing 6 using a jointing product 7 forming a sealing layer lateral.
  • This envelope has its small open base (upper end in the figures) so as to leave free the blowing face 8 of the refractory part.
  • its large base 9 is provided with a tube 10 connected to a pipe 11 for supplying a stirring fluid from a source not shown.
  • the stirring fluid is an inert gas, for example nitrogen or argon.
  • the large base 9 of the envelope is placed slightly away from the refractory part 5 in order to provide a gas distribution chamber 12 between them.
  • the permeability of the refractory part 5 is obtained by virtue of an embodiment of the latter in an assembly of plates 13 made of ordinary compact refractory material (for example made of magnesian concrete). These plates are juxtaposed with interposition between them of longitudinal spacers 14. These are of very reduced format (metal wires) so as to provide between the plates 13 blowing slots 15 of a few tenths of a mm in width only. For reasons of clarity, this width has been deliberately exaggerated in the figures.
  • the slots 15 ensure the passage of the stirring gas by connecting the distribution chamber 12 to the blowing face 8 while avoiding, thanks to their narrowness, untimely infiltration of molten metal.
  • the refractory part 1 is crossed by a metal rod 16 whose upper end is flush with the blowing face 8.
  • This rod and the casing 6, the free edge of which also comes in the plane of the face 8, are preferably made of steel and constitute the two terminal terminals, of opposite polarity, of an open electrical circuit comprising, as can be seen , a power supply 17 (for example an accumulator), a sound signaling device 18 and two flexible connecting wires 19, 19 ′ running in the conduit 11 and the ends of which are welded respectively to the lower end of the rod 16 and to the tube 10 of the envelope 6.
  • a power supply 17 for example an accumulator
  • sound signaling device 18 and two flexible connecting wires 19, 19 ′ running in the conduit 11 and the ends of which are welded respectively to the lower end of the rod 16 and to the tube 10 of the envelope 6.
  • the casing 6 is advantageous for the casing 6 to be well electrically insulated from the rod 16. This insulation is obtained naturally by the refractory part itself. However, the situation can be improved by opting for plates 13 made of non-carbon refractory material. Likewise, the jointing product 7 used preferably has qualities of electrical insulator.
  • the rod 16 in a housing slightly oversized compared to the format of the rod.
  • This housing can easily be produced by means of notches provided facing each other on two adjacent plates 13. The gap is then filled with a non-conductive jointing product, which thus ensures both the desired electrical insulation and the fixing of the rod 16 in the permeable element.
  • Another preventive measure in this regard consists in providing an insulating seal 20 which takes place between the base of the casing 6 and the metal shell 2 of the converter.
  • FIGS. 2 differs from that described above by the fact that a second metal rod 21 is provided in the refractory part 5 to replace the casing 6 in its role as an electrical terminal.
  • This variant is particularly applicable in cases where the blowing element 1 is produced without a metal casing.
  • FIGS. 3 The variant illustrated in FIGS. 3 is of particular interest in that it ensures the detection of the presence of the molten metal against the blowing face 8 while making it possible to follow the evolution of the wear of the element 1 and of the surrounding refractory 4, due to the action of the molten metal.
  • This variant is characterized, as can be seen, by the fact that one of the terminals of the electric detection circuit is constituted by a plurality of metal rods, 22, 23, 24, 25 placed in the refractory part 5.
  • the another electrical terminal is ensured, as for the variant of Figure 1, by the metal casing 6.
  • the rods 22, 23, 24, 25, have different lengths so that their upper ends are staggered at levels offset between them depending on the thickness of the refractory portion 5.
  • One of them, namely the rod 22, is flush with the blowing face 8, and can therefore be placed as in the previous examples in a blowing slot 15.
  • the other rods are buried in holes blinds provided for this purpose within the refractory mass 5 and their lower end portions slightly protrude to allow the electrical connection with the power source 17.
  • This connection operates according to a mounting in parallel of the rods therebetween, and indicators 26, 26 ', 26 ", 26"' (for example indicator lights) indicate the existence of a current in the elementary circuits of each of the rods.
  • the device makes it possible to detect the presence of molten metal against the blowing face 8 as well as, the degree of wear of the element in use by successive exposure of the rods as and when of wear.
  • the accuracy of the measurement is of course directly linked to the level shift between the ends of the rods.
  • the implementation of the invention is very simple. In any case, it poses no uncontrolled problem.
  • the voltage required between the outputs of the electrical source 17 may be low, of the order of only a few volts. Furthermore, this voltage can be continuous or alternating.
  • the flexible electrical connection wires between the terminals and the source 17 are advantageously placed in the pipe 11 for supplying the gas, which ensures that they are kept at temperature thanks to the gas current.
  • metal rods such as 16, 21, 22, etc.
  • metal rods can be replaced by any other body provided that it has electrically conductive properties.
  • Graphite elements may for example be suitable.
  • shape of these bodies can be arbitrary: rods, wires, plates, tubes, etc.
  • the invention can be implemented simply by electing one or two of these nozzles as electrical terminals, depending on whether one has opted for the variant with a conductive envelope (FIG. 1) or not (FIG. 2).
  • the metal rod may not be flush with the surface of the element in the new state.
  • the desired outcrop will occur later during the commissioning of the element, after wear of the refractory to a depth equal to that of the end of the conductive body in the refractory part in new condition.
  • the monitoring of the wear of the blowing element can be carried out by means other than the plurality of level shifting rods.
  • a method for example may consist in continuously determining the resistance of the rod from the measurement of the electric current in the detection circuit.
  • a rod of this type can very well be produced from a rod formed by a calibrated metal wire, of known resistivity with precision, preferably high, and of great developed length, which is wound in solenoid with contiguous turns, around a refractory core for example.
  • the wire must in this case have been previously coated with an insulating varnish.
  • the individual indicators 26, 26 ', 26 ", 26"', provided on the different branches of the parallel assembly can be replaced to detect the passage of current in each of the rods, by a single device sensitive to variations in the total electrical intensity of the circuit, for example, a device provided with a digital analog converter and indicating from the total intensity of the circuit the number of rods or the rank of the rod whose end is exposed.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Mechanical Engineering (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
EP82402268A 1981-12-16 1982-12-13 Elément réfractaire perméable pour l'introduction d'un fluide de brassage dans un bain de métal en fusion Expired EP0082078B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT82402268T ATE14751T1 (de) 1981-12-16 1982-12-13 Durchlaessiger feuerfester bauteil zum einleiten eines ruehrfluides in ein schmelzfluessiges metallbad.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8123649A FR2518240A1 (fr) 1981-12-16 1981-12-16 Element refractaire permeable pour l'introduction d'un fluide de brassage dans un bain de metal en fusion
FR8123649 1981-12-16

Publications (2)

Publication Number Publication Date
EP0082078A1 EP0082078A1 (fr) 1983-06-22
EP0082078B1 true EP0082078B1 (fr) 1985-08-07

Family

ID=9265146

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82402268A Expired EP0082078B1 (fr) 1981-12-16 1982-12-13 Elément réfractaire perméable pour l'introduction d'un fluide de brassage dans un bain de métal en fusion

Country Status (8)

Country Link
EP (1) EP0082078B1 (enrdf_load_stackoverflow)
JP (1) JPS58110624A (enrdf_load_stackoverflow)
AT (1) ATE14751T1 (enrdf_load_stackoverflow)
BR (1) BR8207313A (enrdf_load_stackoverflow)
CA (1) CA1200692A (enrdf_load_stackoverflow)
DE (1) DE3265298D1 (enrdf_load_stackoverflow)
ES (1) ES8401237A1 (enrdf_load_stackoverflow)
FR (1) FR2518240A1 (enrdf_load_stackoverflow)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4481809A (en) * 1983-08-29 1984-11-13 Labate M D Method and apparatus for monitoring erosion in gas stirring devices in molten metal ladles
FR2576911A1 (fr) * 1985-01-31 1986-08-08 Didier Werke Ag Brique refractaire et permeable aux gaz
GB2177485A (en) * 1985-06-28 1987-01-21 Didier Werke Ag Gas purging device
FR2590974A1 (fr) * 1985-12-03 1987-06-05 Detalle Pol Dispositif de detection de l'usure de briques d'insufflation de fluides dans des metaux liquides
US4779849A (en) * 1986-07-12 1988-10-25 Didier-Werke Ag Gas washing device with reduced gas flow upon wear of gas sink
DE3802657C1 (enrdf_load_stackoverflow) * 1988-01-29 1989-09-21 Didier-Werke Ag, 6200 Wiesbaden, De
EP0337982A1 (de) * 1988-04-13 1989-10-18 Veitscher Magnesitwerke-Actien-Gesellschaft Feuerfester, gasdurchlässiger Spülstein
DE102008047541A1 (de) * 2008-09-16 2010-07-08 Vdeh-Betriebsforschungsinstitut Gmbh Verfahren zur Spülgasbehandlung eines flüssigen Metalls

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4131756A1 (de) * 1991-09-24 1993-04-01 Plibrico Gmbh Gasspuelstein
DE10305232B3 (de) * 2003-02-08 2004-08-05 Refractory Intellectual Property Gmbh & Co.Kg Feuerfester keramischer Gasspülstein
JP7038126B2 (ja) * 2017-02-01 2022-03-17 エクセロ カンパニー，リミテッド 被加熱部材の統合管理システム

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3299706A (en) * 1964-04-03 1967-01-24 Latrobe Steel Co Apparatus for measuring molten metal levels in ladles
US3541604A (en) * 1967-02-01 1970-11-17 Nippon Steel Corp Gas insufflating means for a molten metal refining container
DE1958224A1 (de) * 1969-11-20 1971-05-27 Salzgitter Huettenwerk Ag Elektrisches Messverfahren und Vorrichtung zum Bestimmen von Schlackenhoehe und Schlackenmenge bei Schlacke-Metall-Baedern in metallurgischen Gefaessen
SE413074B (sv) * 1976-10-25 1980-04-14 Asea Ab Forfarande for metning av resistiva spenningsfall vid tappstellen fran metallurgiska behallare
FR2455008A1 (fr) * 1979-04-25 1980-11-21 Siderurgie Fse Inst Rech Piece refractaire a permeabilite selective et orientee pour l'insufflation d'un fluide

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4481809A (en) * 1983-08-29 1984-11-13 Labate M D Method and apparatus for monitoring erosion in gas stirring devices in molten metal ladles
FR2576911A1 (fr) * 1985-01-31 1986-08-08 Didier Werke Ag Brique refractaire et permeable aux gaz
DE3503221A1 (de) * 1985-01-31 1986-08-14 Didier-Werke Ag, 6200 Wiesbaden Feuerfester gasdurchlaessiger stein
GB2177485A (en) * 1985-06-28 1987-01-21 Didier Werke Ag Gas purging device
EP0225584A3 (fr) * 1985-12-03 1990-05-02 DETALLE, Pol Dispositif de détection de l'usure de briques d'insufflation de fluides dans des métaux liquides
FR2590974A1 (fr) * 1985-12-03 1987-06-05 Detalle Pol Dispositif de detection de l'usure de briques d'insufflation de fluides dans des metaux liquides
US4779849A (en) * 1986-07-12 1988-10-25 Didier-Werke Ag Gas washing device with reduced gas flow upon wear of gas sink
DE3802657C1 (enrdf_load_stackoverflow) * 1988-01-29 1989-09-21 Didier-Werke Ag, 6200 Wiesbaden, De
EP0337982A1 (de) * 1988-04-13 1989-10-18 Veitscher Magnesitwerke-Actien-Gesellschaft Feuerfester, gasdurchlässiger Spülstein
WO1989009836A1 (en) * 1988-04-13 1989-10-19 Veitscher Magnesitwerke-Actien-Gesellschaft Refractory-gas permeable bubbling plug
US5007366A (en) * 1988-04-13 1991-04-16 Veitscher Magnesitwerke-Actien-Gesellschaft Refractory gas permeable bubbling plug
DE102008047541A1 (de) * 2008-09-16 2010-07-08 Vdeh-Betriebsforschungsinstitut Gmbh Verfahren zur Spülgasbehandlung eines flüssigen Metalls
DE102008047541B4 (de) * 2008-09-16 2014-04-30 Vdeh-Betriebsforschungsinstitut Gmbh Verfahren zur Spülgasbehandlung eines flüssigen Metalls

Also Published As

Publication number Publication date
FR2518240A1 (fr) 1983-06-17
ES518218A0 (es) 1983-11-16
FR2518240B1 (enrdf_load_stackoverflow) 1984-02-24
EP0082078A1 (fr) 1983-06-22
DE3265298D1 (en) 1985-09-12
ATE14751T1 (de) 1985-08-15
BR8207313A (pt) 1983-10-18
CA1200692A (fr) 1986-02-18
ES8401237A1 (es) 1983-11-16
JPS58110624A (ja) 1983-07-01

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