EP0022739B1 - Procédé et dispositif pour la mesure du niveau de la scorie dans un récipient métallurgique et pour l'appréciation de son état physique - Google Patents

Procédé et dispositif pour la mesure du niveau de la scorie dans un récipient métallurgique et pour l'appréciation de son état physique Download PDF

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Publication number
EP0022739B1
EP0022739B1 EP80630021A EP80630021A EP0022739B1 EP 0022739 B1 EP0022739 B1 EP 0022739B1 EP 80630021 A EP80630021 A EP 80630021A EP 80630021 A EP80630021 A EP 80630021A EP 0022739 B1 EP0022739 B1 EP 0022739B1
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EP
European Patent Office
Prior art keywords
crucible
sensors
level
slag
pressure
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
EP80630021A
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German (de)
English (en)
French (fr)
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EP0022739A1 (fr
Inventor
Jean Baumert
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.)
Arcelor Luxembourg SA
Original Assignee
Arbed SA
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Publication date
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=19729200&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0022739(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Arbed SA filed Critical Arbed SA
Priority to AT80630021T priority Critical patent/ATE756T1/de
Publication of EP0022739A1 publication Critical patent/EP0022739A1/fr
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    • 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
    • C21C5/4673—Measuring and sampling devices
    • 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
    • C21C5/30—Regulating or controlling the blowing

Definitions

  • the present invention relates to a method and a device for measuring the level and for assessing the physical state of the slag in a metallurgical vessel, in particular in a steelworks converter.
  • Knowledge of the level of slag in a steelworks converter is important, both from the metallurgical point of view, as a parameter of the degree of refining progress, and from the point of view of safety, in order to prevent overflow .
  • the applicant has developed a system for measuring the level of the slag which allows at the same time an evaluation of the consistency thereof, which constitutes important information, especially for the refining of phosphorous cast irons where a slag of a frothy consistency was considered desirable.
  • This measurement system that the applicant has described in Luxembourg patent N ° 71,261, includes a thermostatically controlled acoustic duct which is placed above the converter and which picks up the noise emitted by the oxygen blowing lance. After filtering the frequencies whose origin is foreign to the parameters which are of interest for the measurement proper, we retain a signal whose interpretation allows us to conclude on the degree of the noise absorbed by the slag and thereby on the degree of the sparkling character present as well 'at its level in the crucible.
  • the object of the invention therefore consisted in proposing a system for measuring the level of the slag and its physical state, this measurement system being largely independent of the degree of foaming of the slag and its performance being at least equivalent to that of the systems. known.
  • the measuring method according to the invention which is characterized in that at least two hydrostatic pressure taps swept by gas jets are provided at different levels above the filling level of the crucible. inert with adjustable flow rate, that the pressures of said intakes are initially adjusted to equal values with each other, that the pressures existing at said intakes are then captured and that the level of slag in the crucible is determined by interpreting the deviations of the measured pressures from their initial values.
  • the scanning of the intakes by means of the inert gas ensures that the mouth on the internal face of the refractory, in which the pressure intakes are housed, is always free and as little as possible affected by d '' possible splashes.
  • the idea which is the basis of the invention therefore consists in measuring and interpreting the differences in hydrostatic pressure determined at several well defined levels above the level of the bath in the crucible.
  • the operating principle of the method is as follows: Consider for example three pressure taps, of which 2 (A1 and A2) are at a same level and the 3rd (B) is placed at a higher level, the difference in levels being equal to H.
  • the three intakes are swept by nitrogen flows such that the pressures P A1 , PA2 and P B are equal if the intakes freely open into the crucible cavity, in other words, in the absence of slag. This situation occurs between the development phases and we take advantage of this to align the three pressures to the same value before the start of blowing.
  • the A1 socket is chosen as the reference socket. Its adjusted nitrogen flow determines the starting value of the pressure P Al . We then cancel the differences P A1 -PA2 resp. P A1 -P B.
  • two sockets are therefore provided at the same level, which, in principle, provide identical results at all times. In other words, they allow a relative appreciation of their behavior. If after a few campaigns we find that the behavior of the 2 catches is satisfactory, that is to say reliable and reproducible, we can delete one of the sockets on level A, as well as the associated equipment.
  • the device necessary for implementing the method according to the invention comprises at least two individual sensors, which are embedded at two different levels in the vertical wall of a crucible.
  • Each sensor comprises a rigid pressure tapping tube housed in the crucible refractory, which tube is attached to a flexible tube which crosses the carcass of the crucible and establishes communication with a conventional pressure measuring instrument.
  • FIG. 1 shows in a nonlimiting manner the diagram of a preferred embodiment of a pressure sensor according to the invention
  • FIG. 2 shows a block diagram of a possible embodiment of the measuring assembly.
  • the pressure tap brick (1) which can be the size of normal neighboring refractory bricks and which contains the pressure tap.
  • This outlet is constituted by a tube made of a refractory material (11), preferably ceramic, which retains its shape, that is to say its cross section for the purging gas, at high temperatures.
  • the tube (11) is housed in a metal tube (12) protecting it with respect to the mechanical forces arising especially during the cooking of the converter and at the start of the campaign until the cooking can be considered as finished.
  • the combination of the two tubes, which wear in parallel with the refractory, must ensure a pressure drop - due to the sweeping gas - stable and reproducible during the whole crucible campaign.
  • the pressure tapping brick On the side of the permanent lining (30), the pressure tapping brick is housed in a mattress of refractory fibers which aims to attenuate the shearing forces to which it risks being exposed at the level of the face separating the two layers of refractory.
  • the pressure tapping brick (1) including the tubes (11), (12) and (13) are wear elements which are replaced each time the crucible is built.
  • the work to be carried out during each replacement is to remove the plug (21), to insert the tube (13), to replace the plug (21), to tighten the packing (22) in order to make the plug watertight vis- opposite the carcass.
  • the pressure is transmitted to the measuring instrument by a tube (41) with a diameter large enough so that there is no appreciable pressure drop due to the flow of the sweeping fluid, in particular the occurrence of nitrogen.
  • the three intakes are swept by nitrogen flow rates such that the pressures P A1 , PA2 and P B are equal if the intakes freely open into the crucible cavity, which is the case in the absence of slag.
  • the three pressures are therefore adjusted to the same value before the start of blowing and / or between the blowing phases.
  • the socket (A1) is chosen as the reference socket.
  • the nitrogen flow (N2) is adjusted manually using a pressure reducer (D).
  • This flow rate determines the starting value of the pressure (P A1 ) '
  • Two regulators (R) cancel the differences P AI -PA2 resp. P AL -P B by action on the valves (VA2) and V B ).
  • This alignment accomplished - operation which takes a few seconds - the regulator inputs (R) are short-circuited which has the effect of freezing the control valves in their last position for example by means of position regulators. In the case of regulating valves controlled by an electric motor, it is sufficient to cut off the output of the regulators (R) in order to block the valves in their last position.
  • the acquisition of A data can be centralized in a computer which is responsible for the transformation of the measurement results into meaningful information for the staff of the steelworks or in a computer which assumes the control of the steel making.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
  • Investigating And Analyzing Materials By Characteristic Methods (AREA)
  • Testing Or Calibration Of Command Recording Devices (AREA)
  • Medical Preparation Storing Or Oral Administration Devices (AREA)
  • Mechanical Treatment Of Semiconductor (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
EP80630021A 1979-07-16 1980-07-02 Procédé et dispositif pour la mesure du niveau de la scorie dans un récipient métallurgique et pour l'appréciation de son état physique Expired EP0022739B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT80630021T ATE756T1 (de) 1979-07-16 1980-07-02 Verfahren und vorrichtung zum messen des niveaus der schlacke in einem metallurgischen gefaess und zur beurteilung ihres physischen zustandes.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
LU81512A LU81512A1 (fr) 1979-07-16 1979-07-16 Procede et dispositif pour la mesure du niveau de la scorie dans un recipient metallurgique et pour l'appreciation de son etat physique
LU81512 1979-07-16

Publications (2)

Publication Number Publication Date
EP0022739A1 EP0022739A1 (fr) 1981-01-21
EP0022739B1 true EP0022739B1 (fr) 1982-03-17

Family

ID=19729200

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80630021A Expired EP0022739B1 (fr) 1979-07-16 1980-07-02 Procédé et dispositif pour la mesure du niveau de la scorie dans un récipient métallurgique et pour l'appréciation de son état physique

Country Status (12)

Country Link
US (1) US4359211A (pt)
EP (1) EP0022739B1 (pt)
JP (1) JPS5616614A (pt)
AT (1) ATE756T1 (pt)
AU (1) AU6041580A (pt)
BR (1) BR8004359A (pt)
CA (1) CA1159923A (pt)
DE (1) DE3060230D1 (pt)
ES (1) ES493399A0 (pt)
LU (1) LU81512A1 (pt)
PT (1) PT71535A (pt)
ZA (1) ZA804241B (pt)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19962632C2 (de) * 1998-12-24 2002-05-16 Woojin Inc Verfahren zur Messung der Dicke einer Schlacke bei der Stahlherstellung

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5963520U (ja) * 1982-10-21 1984-04-26 株式会社河合楽器製作所 ミキサ
JPS59114716U (ja) * 1983-01-25 1984-08-02 古河電気工業株式会社 ケ−ブル貫通部
JPH0688127B2 (ja) * 1988-03-09 1994-11-09 川崎製鉄株式会社 スラグ流出検知方法
US5289716A (en) * 1992-08-21 1994-03-01 The United States Of America As Represented By The United States Department Of Energy Monitoring and analyzing waste glass compositions
US5650117A (en) * 1995-09-27 1997-07-22 Vesuvius Crucible Company Slag detecting apparatus and method
US6130637A (en) * 1998-08-18 2000-10-10 Usx Corporation Measuring the thickness of hot slag in steelmaking
US6166681A (en) * 1998-08-18 2000-12-26 Usx Corporation Measuring the thickness of materials
JP2010090675A (ja) * 2008-10-10 2010-04-22 Daiwa Kiko Kk 側壁撤去装置
US8482295B2 (en) * 2009-02-23 2013-07-09 Hatch Ltd. Electromagnetic bath level measurement for pyrometallurgical furnaces
AT514132B1 (de) 2013-03-25 2015-11-15 Voestalpine Stahl Gmbh Verfahren zur Bestimmung von Reaktionsdaten eines Reaktionsablaufs
TWI706124B (zh) 2019-09-04 2020-10-01 國立中央大學 物性測量裝置及測量物性的方法

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1457406A (en) * 1919-06-19 1923-06-05 Pneumercator Company Depth and specific-gravity measuring apparatus
FR1481242A (fr) * 1966-04-07 1967-05-19 Gaz De France Procédé et dispositif de mesure de la hauteur d'un liquide contenu dans une cuve ou analogue
AT260962B (de) * 1963-02-21 1968-04-10 Waagner Biro Ag Verfahren zur Steuerung des Verbrennungsvorganges von Gasen sowie Vorrichtung zur Durchführung dieses Verfahrens
DE1274146B (de) * 1965-08-26 1968-08-01 Foerderung Der Eisenhuettentec Vorrichtung zum kontinuierlichen Messen der Temperatur von Konverterschmelzen
DE1508250B1 (de) * 1966-10-27 1970-04-09 Siemens Ag Anordnung zur Messung der Temperatur von Metallschmelzen,vorzugsweise in Konvertergefaessen
US3620085A (en) * 1969-03-27 1971-11-16 Cermat Apparatus for measuring the level of liquid in a reservoir
DE2239216A1 (de) * 1971-08-18 1973-05-03 Allegheny Ludlum Ind Inc Anordnung und verfahren zum ermitteln der eintauchtiefe einer lanze
DE2452655A1 (de) * 1973-11-08 1975-06-12 Cermat Verfahren und vorrichtung zum messen des standes und des spezifischen gewichts einer in behaeltern grossen fassungsvermoegens enthaltenen fluessigkeit
JPS5252108A (en) * 1975-10-24 1977-04-26 Nippon Steel Corp Pocess for efining by converter
DE2834737A1 (de) * 1977-08-26 1979-03-08 British Steel Corp Stahlherstellungsverfahren
LU81207A1 (fr) * 1979-04-30 1980-12-16 Arbed Procede d'affinage d'un bain de metal contenant des matieres refroidissantes solides

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FR481242A (fr) * 1916-03-16 1916-11-14 Secondo Torta & Cie Soc Bougie d'allumage pour moteurs à explosions
US3200971A (en) * 1961-08-01 1965-08-17 Owens Corning Fiberglass Corp Apparatus and method for controlling liquid level
FR1363687A (fr) * 1963-07-17 1964-06-12 Bot Brassert Oxygen Technik Ag Procédé et dispositif de réglage de fonctionnement pour opérations de soufflage ou pour des méthodes analogues d'affinage métallurgique
US3476538A (en) * 1965-10-24 1969-11-04 Owens Corning Fiberglass Corp Process and apparatus for controlling the flow of molten glass
FR1540757A (fr) * 1967-10-12 1968-09-27 Beteiligungs & Patentverw Gmbh Procédé et dispositif pour déterminer l'état des scories dans un convertisseur
CH475551A (de) * 1968-05-31 1969-07-15 Brehm Dr Ingbureau Ag Füllstandsanzeiger an Behälter für flüssiges oder pulverförmiges Gut
US3590843A (en) * 1969-10-23 1971-07-06 Gen Electric Multiple-jet liquid level detector
DE2354003C2 (de) * 1973-10-27 1975-02-13 Stahlwerke Peine-Salzgitter Ag, 3150 Peine Verfahren und Vorrichtung zur Überwachung und Steuerung des Reaktionsablaufes beim Frischen von Roheisen Stahlwerke Peine-Salzgitter AG, 315OPeine
US3850416A (en) * 1974-01-04 1974-11-26 Ford Motor Co Slag depth indicator
FR2340156A2 (fr) * 1976-02-03 1977-09-02 Pechiney Aluminium Procede et dispositif de moulage sous basse pression
DE2706558A1 (de) * 1976-03-15 1977-09-22 Erwin Buehrer Verfahren und einrichtung zum abgiessen einer form mit einer waehlbaren menge von fluessigem metall
US4102190A (en) * 1977-04-07 1978-07-25 Bethlehem Steel Corporation Method and apparatus for determining the weight of slag on a bath of molten metal
US4288062A (en) * 1979-08-09 1981-09-08 Holcroft Apparatus for control and monitoring of the carbon potential of an atmosphere in a heat-processing furnace

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1457406A (en) * 1919-06-19 1923-06-05 Pneumercator Company Depth and specific-gravity measuring apparatus
AT260962B (de) * 1963-02-21 1968-04-10 Waagner Biro Ag Verfahren zur Steuerung des Verbrennungsvorganges von Gasen sowie Vorrichtung zur Durchführung dieses Verfahrens
DE1274146B (de) * 1965-08-26 1968-08-01 Foerderung Der Eisenhuettentec Vorrichtung zum kontinuierlichen Messen der Temperatur von Konverterschmelzen
FR1481242A (fr) * 1966-04-07 1967-05-19 Gaz De France Procédé et dispositif de mesure de la hauteur d'un liquide contenu dans une cuve ou analogue
DE1508250B1 (de) * 1966-10-27 1970-04-09 Siemens Ag Anordnung zur Messung der Temperatur von Metallschmelzen,vorzugsweise in Konvertergefaessen
US3620085A (en) * 1969-03-27 1971-11-16 Cermat Apparatus for measuring the level of liquid in a reservoir
DE2239216A1 (de) * 1971-08-18 1973-05-03 Allegheny Ludlum Ind Inc Anordnung und verfahren zum ermitteln der eintauchtiefe einer lanze
DE2452655A1 (de) * 1973-11-08 1975-06-12 Cermat Verfahren und vorrichtung zum messen des standes und des spezifischen gewichts einer in behaeltern grossen fassungsvermoegens enthaltenen fluessigkeit
JPS5252108A (en) * 1975-10-24 1977-04-26 Nippon Steel Corp Pocess for efining by converter
DE2834737A1 (de) * 1977-08-26 1979-03-08 British Steel Corp Stahlherstellungsverfahren
LU81207A1 (fr) * 1979-04-30 1980-12-16 Arbed Procede d'affinage d'un bain de metal contenant des matieres refroidissantes solides

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19962632C2 (de) * 1998-12-24 2002-05-16 Woojin Inc Verfahren zur Messung der Dicke einer Schlacke bei der Stahlherstellung

Also Published As

Publication number Publication date
CA1159923A (fr) 1984-01-03
ATE756T1 (de) 1982-04-15
ES8103179A1 (es) 1981-02-16
EP0022739A1 (fr) 1981-01-21
JPS5616614A (en) 1981-02-17
ZA804241B (en) 1981-07-29
DE3060230D1 (en) 1982-04-15
AU6041580A (en) 1981-01-22
BR8004359A (pt) 1981-01-27
US4359211A (en) 1982-11-16
PT71535A (fr) 1980-08-01
ES493399A0 (es) 1981-02-16
LU81512A1 (fr) 1981-02-03

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