EP0086694B1 - Lance d'injection de gaz pour convertisseur métallurgique - Google Patents

Lance d'injection de gaz pour convertisseur métallurgique Download PDF

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Publication number
EP0086694B1
EP0086694B1 EP83400234A EP83400234A EP0086694B1 EP 0086694 B1 EP0086694 B1 EP 0086694B1 EP 83400234 A EP83400234 A EP 83400234A EP 83400234 A EP83400234 A EP 83400234A EP 0086694 B1 EP0086694 B1 EP 0086694B1
Authority
EP
European Patent Office
Prior art keywords
lance
series
chamber
tube
gas
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
EP83400234A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0086694A1 (fr
Inventor
Hugues Zanetta
Daniel Richard
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
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 Institut de Recherches de la Siderurgie Francaise IRSID filed Critical Institut de Recherches de la Siderurgie Francaise IRSID
Priority to AT83400234T priority Critical patent/ATE27003T1/de
Publication of EP0086694A1 publication Critical patent/EP0086694A1/fr
Application granted granted Critical
Publication of EP0086694B1 publication Critical patent/EP0086694B1/fr
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D3/00—Charging; Discharging; Manipulation of charge
    • F27D3/16—Introducing a fluid jet or current into the charge
    • 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
    • C21C5/4606—Lances or injectors
    • 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
    • C21C5/305—Afterburning

Definitions

  • the present invention relates to a gas injection lance specially designed for metallurgical converters with oxygen blowing from above, by the fact that it makes it possible to produce two concentric gas flows under different generating pressures.
  • Lances are commonly used in metallurgical converters which inject oxygen to the surface of a liquid metal to be refined, such as cast iron or steel. It is known that it is often advantageous, in this kind of operation, to complete the refining reaction of the molten metal by a secondary combustion of the gases which are released from the metal bath, this secondary combustion requiring a pressure which generates oxygen. lower and an annular distribution of the injection around the, or, more generally, the central primary jets with strong impulse ensuring the conversion of the bath. For this, we use - as shown for example in document LU-A-78906 - so-called "double flow" lances, supplied by two separate oxygen circuits at different generating pressures from outside the converter. However, it is known that it is not always easy to implement such dual-flow lances, with two separate feeds, and difficulties may arise with regard to the individual controls of each flow.
  • the present invention makes it possible to avoid these drawbacks thanks to a lance specially designed to produce, from a single supply source of the lance, two different generating pressures, that generating the secondary flow being insensitive to the fluctuations of the other , which generates the main flow.
  • the lance according to the invention also has the advantage of being able to be easily mounted on existing installations using single-flow lances, often even by replacing only the nose of the lance, that is to say the extreme part. the closest, to the liquid metal bath and from which the gas flows come out.
  • the invention thus relates to a gas injection lance comprising an internal chamber for admitting a main gas flow to a first series of injection orifices and, inside said chamber, means for formation of a secondary flow delivered to a second series of outlet orifices, said means taking a fraction of the main flow in the internal chamber, lance characterized in that said means are constituted by necks at speed of sonic flow followed by expansion pots and connected to the second series of outlet orifices and in that said second series of outlet orifices is arranged annularly around the first series of injection orifices.
  • the necks with a sonic flow speed which open in the inlet chamber of the main flow, each at the inlet of a pressure reducing valve, individually supply only one of the orifices of injection of the second series.
  • This solution where the secondary flow is taken separately for each of the orifices to which it is brought, is most often preferable.
  • a common collector distributing the secondary flow thus withdrawn and expanded towards the various outlet orifices.
  • the lance according to the invention is particularly suitable for being mounted on a metallurgical converter with top-refining oxygen blowing (type LD), so as to allow the injection of oxygen in the direction of the surface of a metal bath during refining.
  • the lance can then include all the ancillary equipment known in this kind of application, for example means for cooling by circulation of water in a jacket surrounding the wall of the inlet chamber of the main gas flow.
  • the secondary blowing orifices are advantageously oriented, as in conventional double-flow lances, at an inclination, relative to the axis, greater than for the main flow injection orifices. This arrangement, combined with the reduced speed of the secondary flow, ensures the best secondary combustion in a converter, because this secondary flow occupies a conical annular space which widens and widens around the central cone formed by the main flow.
  • the lance according to the invention comprises means for adjusting the sampling of secondary flow in the internal chamber of the lance which may advantageously be constituted by means for adjusting the pass section of the necks through which this sampling is carried out at sonic flow speed.
  • the more or less great restriction of the passage section has an effect on the quantity of gas withdrawn and therefore on the generating pressure obtained, after the expansion waves, at the outlet orifices of the series corresponding to the secondary flow.
  • the adjustment can be carried out by the end of the lance opposite to that of the nose which comprises the outlet orifices.
  • Any device known per se can be used to modify the internal section of the necks according to the needs of this adjustment.
  • the section of the necks is chosen to be strictly less than the section of the outlet openings of the secondary flow, which is sufficient to ensure a sonic speed of the flow in the necks under the pressure conditions usually prevailing in the internal chamber. of the lance (the pressure there always being greater than 10 bars, while the lower pressure limit not to be exceeded is close to 2 bars).
  • FIG 1 there is shown a converter 1 containing a liquid metal 2 being refined.
  • the refining reaction is carried out by blowing oxygen onto the surface of the metal.
  • the converter is equipped for this with a lance 3, arranged vertically in the axis of the converter.
  • the lance 3 is essentially constituted by a tubular wall 4, closed at the lower end by a nose through which are pierced the blowing orifices designated under the general reference 6.
  • FIG. 1 therefore shows the two coaxial walls 8 and 9 which surround the lance, as well as the nozzles 10 and 11 for the inlet and outlet of the cooling water respectively.
  • Figures 1 and 5 show how are distributed and arranged the orifices 6 through which the oxygen supplied under pressure in the lance leaves at the lower end thereof.
  • Figure 2 shows more precisely how these holes are made.
  • These are in fact blowing pipes (12, 13) open at their two ends and passing through the wall of the lance and its double water circulation jacket. They are divided into two concentric series or crowns. All are inclined relative to the axis of the lance, deviating from this axis from the inside towards the outside of the lance.
  • a primary blowing cone 14, or main in the axis of the lance is formed in operation, at the outlet of the orifices 47 of the pipes 12 of the internal series, while the pipes 13 of the series external ensure, through their orifices 48, a secondary oxygen blowing 15 which widens annularly around the main cone 14.
  • the nose of the lance is produced as shown in FIG. 2. It shows an internal chamber 16 delimited by the tubular wall 4, which is completed by an end piece 17 which constitutes its bottom.
  • the seal between the wall 4 itself and the bottom 17 is produced by a fitting assembly with interposition of seals 18 to compensate for the effects of differential expansion with the rest of the lance body.
  • two coaxial skirts 20 and 21 which are connected to the tubular casings 8 and 9 respectively of the double cooling jacket.
  • the external skirt 21 is welded to the end of the external envelope 9.
  • the intermediate skirt 20 fits freely in the end of the envelope 8, intermediate between the wall 4 and the outer envelope 9. Its bottom 23 only consists of radial lugs which pass around the tubes 12 and 13 and leave an opening 24 in the axis of the lance. The circulation of the cooling water is thus ensured as illustrated by the arrows in FIG. 2, the water descending along the tubular wall 4 and rising in the annular space between the intermediate casing 8 and the outer casing 9.
  • the tubes of the internal crown are of larger diameter than the tubes of the external crown and that they are slightly conical, whereas the tubes of the crown external are cylindrical.
  • these details which are advantageous in the particular case represented, are in general by no means imperative.
  • expansion pots 26 In the internal chamber 16 receiving the oxygen under pressure are arranged expansion pots 26, in a number equal to that of the blowing tubes 13 of the outer ring.
  • Each pot 26 forms an elongated vertical cylindrical enclosure which conducts oxygen taken from the chamber 16 individually to one of the outlet orifices 48 of the blowing pipes 13 of the external crown. Its lower end is connected to a bent extension 28 of the corresponding pipes 13, inside the chamber 16. In the particular case shown. this end is constituted by a tip 27 welded to the pot 26 and screwed onto a socket 30 itself welded to the end of the extension 28.
  • the internal section of the pipes 13 is smaller than that of the pots 26, which leads to having the connector ends 27 with a profile converging in the direction of blowing to speed up the gas in the pipes 13.
  • the pot 26 opens in the chamber 16 by a neck of reduced section 29.
  • This neck is formed with a converging entry in a nozzle 31 attached to the end of the cylindrical chamber of the pot 26. Its section is lower than that of the corresponding outlet orifice 48.
  • the expansion pot can add to the expansion pot an adjustment system making it possible to vary the section of passage of the necks 29, and therefore to adjust the gas flow that they take, which leads to modify the pressure generating the secondary flow at the outlet of the expansion pots.
  • FIG. 3 illustrates a possibility of making such a system.
  • a blowing tube 13 with its internal extension 28, the corresponding cylindrical expansion pot 26, terminated by the neck 29.
  • the passage section of the neck 29 can be partially closed off with a needle 33 which can be moved above this neck, parallel to its axis.
  • the displacement of the needle 33 is ensured by a jack 34 mounted on a support 35 fixed on the upper end of the pot 26. It was assumed here that the jack was hydraulically or pneumatically operated (using of a fluid, such as water or a compressed gas inert with respect to oxygen), provided from outside the lance.
  • a fluid such as water or a compressed gas inert with respect to oxygen
  • FIG. 4 illustrates another embodiment of a lance according to the invention, which differs from that of FIG.
  • the neck itself is defined by a flexible deformable membrane 42, mounted in leaktight manner between the upper end of the pot 26 and a rigid annular ring 43.
  • An annular chamber 44 is formed around the flexible membrane 42 by an enclosure 45 fixed in a sealed manner, on the one hand on the upper end of the pot 26, on the other hand on the ring 43.
  • a pipe 46 makes it possible to admit into this chamber a control fluid under an adjustable pressure from the outside of the spear. According to this pressure, the membrane 42 is more or less deformed and swollen towards the axis of the neck where the oxygen circulates, which gives the latter a more or less narrowed passage section.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Manufacture And Refinement Of Metals (AREA)
EP83400234A 1982-02-10 1983-02-04 Lance d'injection de gaz pour convertisseur métallurgique Expired EP0086694B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83400234T ATE27003T1 (de) 1982-02-10 1983-02-04 Aufblasbare injektionslanze fuer einen metallurgischen konverter.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8202173 1982-02-10
FR8202173A FR2521167B1 (fr) 1982-02-10 1982-02-10 Lance d'injection de gaz pour convertisseur metallurgique

Publications (2)

Publication Number Publication Date
EP0086694A1 EP0086694A1 (fr) 1983-08-24
EP0086694B1 true EP0086694B1 (fr) 1987-05-06

Family

ID=9270861

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83400234A Expired EP0086694B1 (fr) 1982-02-10 1983-02-04 Lance d'injection de gaz pour convertisseur métallurgique

Country Status (9)

Country Link
US (1) US4432534A (enrdf_load_stackoverflow)
EP (1) EP0086694B1 (enrdf_load_stackoverflow)
JP (1) JPS58147510A (enrdf_load_stackoverflow)
AT (1) ATE27003T1 (enrdf_load_stackoverflow)
BR (1) BR8300661A (enrdf_load_stackoverflow)
CA (1) CA1194302A (enrdf_load_stackoverflow)
DE (1) DE3371367D1 (enrdf_load_stackoverflow)
ES (1) ES519658A0 (enrdf_load_stackoverflow)
FR (1) FR2521167B1 (enrdf_load_stackoverflow)

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3509795C1 (de) * 1985-03-19 1986-06-05 Klöckner CRA Technologie GmbH, 4100 Duisburg Wassergekuehlte Blaslanze zum Aufblasen von Sauerstoff auf eine Metallschmelze
US4902484A (en) * 1985-07-18 1990-02-20 John Zink Company Oxygen injector means for secondary reformer
LU86329A1 (fr) * 1986-02-28 1987-09-10 Arbed Tuyere pour lance d'affinage
US5297390A (en) * 1992-11-10 1994-03-29 Solar Turbines Incorporated Fuel injection nozzle having tip cooling
US5377960A (en) * 1993-03-01 1995-01-03 Berry Metal Company Oxygen/carbon blowing lance assembly
US5370309A (en) * 1993-05-19 1994-12-06 A. H. Tallman Bronze Company Limited Liquid cooled nozzle
BE1009743A3 (fr) * 1995-06-23 1997-07-01 Thomas Jacques Tuyere de soufflage a oxygene siderurgique.
US6217824B1 (en) 1999-05-20 2001-04-17 Berry Metal Company Combined forged and cast lance tip assembly
FR2797738A1 (fr) * 1999-08-18 2001-02-23 Air Liquide Procede d'injection d'un gaz supersonique dans un four a arc electrique et four a arc pour la mise en oeuvre de ce procede
BE1013686A3 (fr) * 2000-09-15 2002-06-04 Thomas Jacques Nez de lance de soufflage.
WO2007054957A1 (en) * 2005-11-10 2007-05-18 Tata Steel Limited An improved lance for ld steelmaking
CA2657393A1 (en) * 2006-04-21 2007-11-01 Berry Metal Company Metal making lance tip assembly
AT506984B1 (de) * 2008-06-17 2010-06-15 Siemens Vai Metals Tech Gmbh Sauerstoffblaslanze mit schutzelement
BE1023609B1 (fr) 2016-04-15 2017-05-16 Soudobeam Sa Nez de lance de soufflage
BE1023582B1 (fr) 2016-04-15 2017-05-09 Soudobeam Sa Nez de lance de soufflage
WO2017178608A1 (fr) 2016-04-15 2017-10-19 Soudobeam Sa Nez de lance de soufflage
CN114196798B (zh) * 2021-11-23 2023-03-28 武汉钢铁有限公司 单流道二次燃烧氧枪及其使用方法

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LU78906A1 (fr) * 1978-01-19 1979-09-06 Arbed Procede et dispositif pour l'affinage d'un bain de metal

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE845643C (de) * 1949-09-21 1952-08-04 Oesterr Alpine Montan Vorrichtung und Verfahren zum Blasen von Gasen gegen die Oberflaeche von Metallschmelzen
LU39169A1 (enrdf_load_stackoverflow) * 1960-09-12 1960-11-12
US3141763A (en) * 1961-08-29 1964-07-21 Italsider Spa Process and device for the intensive use of oxygen in open-hearth furnaces for producing steel
FR1346214A (fr) * 1963-02-02 1963-12-13 Demag Ag Lance pour souffler de l'oxygène notamment dans les fours à affiner l'acier ou lesconvertisseurs
BE648779A (enrdf_load_stackoverflow) * 1963-10-23 1964-10-01
US3411716A (en) * 1966-05-11 1968-11-19 United States Steel Corp Oxygen lance for steelmaking furnaces
DE2040724A1 (de) * 1970-08-17 1972-02-24 Messer Griesheim Gmbh Duese fuer Brenner oder Sauerstoffblaslanzen
GB1446612A (en) * 1973-03-09 1976-08-18 British Steel Corp Oxygen lances
SU840119A1 (ru) * 1979-09-25 1981-06-23 Институт черной металлургии Фурма доменной печи
FR2496699B1 (fr) * 1980-12-22 1985-06-21 Siderurgie Fse Inst Rech Lance de soufflage de gaz oxydant, notamment d'oxygene, pour le traitement des metaux en fusion

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
LU78906A1 (fr) * 1978-01-19 1979-09-06 Arbed Procede et dispositif pour l'affinage d'un bain de metal

Also Published As

Publication number Publication date
FR2521167A1 (fr) 1983-08-12
DE3371367D1 (en) 1987-06-11
BR8300661A (pt) 1983-11-08
FR2521167B1 (fr) 1987-04-30
JPH0249368B2 (enrdf_load_stackoverflow) 1990-10-30
ES8401138A1 (es) 1983-12-01
ES519658A0 (es) 1983-12-01
EP0086694A1 (fr) 1983-08-24
US4432534A (en) 1984-02-21
CA1194302A (fr) 1985-10-01
ATE27003T1 (de) 1987-05-15
JPS58147510A (ja) 1983-09-02

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