EP0099348B1 - Porous tip for an injection lance for stirring steel by injection - Google Patents

Porous tip for an injection lance for stirring steel by injection Download PDF

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Publication number
EP0099348B1
EP0099348B1 EP83870064A EP83870064A EP0099348B1 EP 0099348 B1 EP0099348 B1 EP 0099348B1 EP 83870064 A EP83870064 A EP 83870064A EP 83870064 A EP83870064 A EP 83870064A EP 0099348 B1 EP0099348 B1 EP 0099348B1
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EP
European Patent Office
Prior art keywords
bushing
grill
porous material
porous
cylindrical
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
EP83870064A
Other languages
German (de)
French (fr)
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EP0099348A1 (en
Inventor
René Desaar
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Individual
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Individual
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Publication date
Application filed by Individual filed Critical Individual
Priority to AT83870064T priority Critical patent/ATE28478T1/en
Publication of EP0099348A1 publication Critical patent/EP0099348A1/en
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Publication of EP0099348B1 publication Critical patent/EP0099348B1/en
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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
    • C21C5/4606—Lances or injectors
    • C21C5/4613—Refractory coated lances; Immersion lances
    • 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
    • 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

Definitions

  • the present invention relates to a porous nose intended to be fixed to the end of a blowing lance in order to cause bubbling of the steel.
  • a blowing lance provided with a porous nose with central cavity is known from the publications LU-A-70 375 and FR-A-2 384 569.
  • the noses described in these publications have a very small cavity located towards the end of the nose with a relatively small diffusion surface for the gas.
  • the invention relates to a porous nose which is both resistant and produces optimal diffusion of the bubbling gas thanks to a larger diffusion surface than in the devices of the prior art.
  • a porous nose characterized by a cylindrical central cavity which extends over a major part of the height of the body of porous material, and by a wide mesh screen embedded in the porous material constituting the body, said screen having a cylindrical part which concentrically surrounds a large part of the central cavity and ends in an end wall arranged in alignment with the terminal orifice of the central cylindrical cavity, the mesh being welded to a metal washer fixed to the end of the bust.
  • At least one anchoring element is embedded in the porous material constituting the body and is welded to the nozzle, this anchoring element having a cylindrical shape and concentrically surrounding the wide mesh screen.
  • the nose is capable of creating a much greater number of bubbles, which makes the bubbling operation more efficient, and that it is possible to easily avoid plugging of the nose by maintaining the neutral gas pressure in the nose for a short time to allow the slag and steel to solidify.
  • the replacement of the nose can be done very quickly.
  • the porous nose comprises a cylindrical body 1, made of porous concrete for example, integral with a threaded nozzle 2 intended for fixing the nose to the end of a blowing lance known per se.
  • the porous body 1 having for example a diameter of 220 mm is formed with a cylindrical central cavity 3, of 60 mm in diameter to serve as a compression chamber for a neutral gas (argon or nitrogen for example).
  • the chamber 3 is in communication with the interior of the nozzle 2.
  • a wide mesh screen 4 which serves to reinforce the body 1 in order to make it more resistant to handling and avoid cracking due to thermal shock.
  • a washer 5 is welded onto which the screen 4 is fixed.
  • the chamber 3 is formed by passing through the opening of the nozzle 2, a cylindrical wooden body having the desired diameter for the chamber 3 and which exceeds the washer 5 of a length equal to the desired length for said compression chamber. Then pour the porous concrete to form the body 1, then remove the wooden body.
  • a cylindrical piece 6 serving as an anchoring element for more firmly fixing the porous concrete.
  • the upper external face of the nose body is advantageously provided with an annular baffle 7 to avoid the penetration of the liquid bath along the joint of the nose with the nozzle 2.

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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)
  • Treatment Of Steel In Its Molten State (AREA)
  • Adjustment Of Camera Lenses (AREA)
  • Coating With Molten Metal (AREA)
  • Nozzles (AREA)
  • Sampling And Sample Adjustment (AREA)
  • Joining Of Building Structures In Genera (AREA)
  • Continuous Casting (AREA)
  • Materials For Medical Uses (AREA)
  • Powder Metallurgy (AREA)
  • Orthopedics, Nursing, And Contraception (AREA)

Abstract

A porous nozzle for blowing gas through a bath of steel, comprises a body (1) of solid porous material, having on its upper face a bushing (2) for securing the body to the end of a blowing lance. The body is formed with a central cylindrical cavity (3) which is in communication with the interior of the bushing (2) for receiving an inert gas from the lance. A large mesh grill (4) which is embedded in the body, encloses the central cavity (3) so as to reinforce the porous material of the body (1). A metal ring (5) is secured about the bushing (2), and the grill (4) is welded to this metal ring (5). There is an anchoring member (6) welded to the periphery of the bushing (2) so as to fasten more securely the porous material constituting the body (1), this anchoring member being embedded in the porous material. The anchoring member (6) is cylindrical and lies outside of and is concentric with the grill (4 ). The grill (4) is cylindrical and terminates in an end wall formed by the large mesh grill (4), this end wall being disposed in alignment with the central cavity (3).

Description

La présente invention concerne un nez poreux destiné a être fixé à l'extrémité d'une lance de soufflage afin de provoquer le bullage de l'acier.The present invention relates to a porous nose intended to be fixed to the end of a blowing lance in order to cause bubbling of the steel.

Jusqu'à ce jour, le bullage de l'acier se fait soit à l'aide d'une brique poreuse que l'on place dans le fond de la poche de coulée, soit à l'aide d'une lance munie d'un nez à trou central. L'utilisation de la brique poreuse a pour inconvénient que la brique doit être remplacée après un nombre de coulées très restreint et chaque fois que la brique est remplacée, il est nécessaire de refroidir complètement la poche pour permettre les manipulations. En outre, il est nécessaire de surveiller soigneusement la poche à chaque coulée pour éviter la percée de la poche.To date, the bubbling of the steel has been carried out either using a porous brick which is placed in the bottom of the ladle, or using a lance provided with a nose with a central hole. The use of porous brick has the disadvantage that the brick must be replaced after a very limited number of castings and each time the brick is replaced, it is necessary to completely cool the bag to allow handling. In addition, it is necessary to carefully monitor the ladle at each pouring to avoid the piercing of the ladle.

La lance à trou de soufflage central a pour inconvénient que le bullage est trop puissant et que la métallurgie en poche ne donne pas les mêmes résultats qu'avec la brique poreuse.The drawback with a central blowing hole has the disadvantage that the bubbling is too powerful and that the pocket metallurgy does not give the same results as with porous brick.

Une lance de soufflage munie d'un nez poreux avec cavité centrale est connue par les publications LU-A-70 375 et FR-A-2 384 569. Les nez décrits dans ces publications comportent une très petite cavité située vers l'extrémité du nez avec une surface de diffusion pour le gaz relativement réduite.A blowing lance provided with a porous nose with central cavity is known from the publications LU-A-70 375 and FR-A-2 384 569. The noses described in these publications have a very small cavity located towards the end of the nose with a relatively small diffusion surface for the gas.

L'invention a pour objet un nez poreux à la fois résistant et produisant une diffusion optimale du gaz de bullage grâce à une surface de diffusion plus importante que dans les dispositifs de l'art antérieur.The invention relates to a porous nose which is both resistant and produces optimal diffusion of the bubbling gas thanks to a larger diffusion surface than in the devices of the prior art.

Cet objectif est atteint par un nez poreux caractérisé par une cavité centrale cylindrique qui s'étend sur une majeure partie de la hauteur du corps en matière poreuse, et par un grillage à mailles larges noyé dans la matière poreuse constituant le corps, ledit grillage ayant une partie cylindrique qui entoure concentriquement une partie importante de la cavité centrale et se termine par une paroi terminale disposée dans l'alignement de l'orifice terminal de la cavité cylindrique centrale, le grillage étant soudé à une rondelle métallique fixée à l'extrémité de la buselure.This objective is achieved by a porous nose characterized by a cylindrical central cavity which extends over a major part of the height of the body of porous material, and by a wide mesh screen embedded in the porous material constituting the body, said screen having a cylindrical part which concentrically surrounds a large part of the central cavity and ends in an end wall arranged in alignment with the terminal orifice of the central cylindrical cavity, the mesh being welded to a metal washer fixed to the end of the bust.

Avantageusement, au moins un élément d'ancrage est noyé dans la matière poreuse constituant le corps et est soudé sur la buselure, cet élément d'ancrage ayant une forme cylindrique et entourant concentriquement le grillage à mailles larges.Advantageously, at least one anchoring element is embedded in the porous material constituting the body and is welded to the nozzle, this anchoring element having a cylindrical shape and concentrically surrounding the wide mesh screen.

Les avantages découlant de cette réalisation sont que le nez est capable de créer un nombre beaucoup plus grand de bulles, ce qui rend l'opération de bullage plus efficace, et qu'il est possible d'éviter aisément le bouchage du nez en maintenant la pression de gaz neutre dans le nez pendant un court laps de temps de façon à permettre la solidification du laitier et de l'acier. Par ailleurs, le remplacement du nez peut se faire très rapidement.The advantages arising from this embodiment are that the nose is capable of creating a much greater number of bubbles, which makes the bubbling operation more efficient, and that it is possible to easily avoid plugging of the nose by maintaining the neutral gas pressure in the nose for a short time to allow the slag and steel to solidify. In addition, the replacement of the nose can be done very quickly.

L'invention est exposée dans ce qui suit à l'aide d'un exemple de mode d'exécution illustré sur le dessin ci-annexé.The invention is set out in the following with the aid of an exemplary embodiment illustrated in the attached drawing.

Le nez poreux comprend un corps cylindrique 1, en béton poreux par exemple, solidaire d'une buselure à filet 2 déstinée à la fixation du nez à l'extrémité d'une lance de soufflage connue en soi. Le corps poreux 1 ayant par exemple un diamètre de 220 mm est formé avec une cavité centrale cylindrique 3, de 60 mm de diamètre devant servir de chambre de compression pour un gaz neutre (argon ou azote par exemple). La chambre 3 est en communication avec l'intérieur de la buselure 2. Dans la matière du corps 1 et entourant les parois de la chambre 3 est noyé un grillage à mailles larges 4 qui sert à armer le corps 1 afin de rendre celui-ci plus résistant aux manipulations et éviter les fissurations dues aux chocs thermiques.The porous nose comprises a cylindrical body 1, made of porous concrete for example, integral with a threaded nozzle 2 intended for fixing the nose to the end of a blowing lance known per se. The porous body 1 having for example a diameter of 220 mm is formed with a cylindrical central cavity 3, of 60 mm in diameter to serve as a compression chamber for a neutral gas (argon or nitrogen for example). The chamber 3 is in communication with the interior of the nozzle 2. In the material of the body 1 and surrounding the walls of the chamber 3 is embedded a wide mesh screen 4 which serves to reinforce the body 1 in order to make it more resistant to handling and avoid cracking due to thermal shock.

Lorsque le nez 1 fixé à l'extrémité d'une lance de soufflage est introduit dans un bain d'acier et alimenté en gaz neutre qui vient emplir la chambre de compression 3, ce gaz neutre diffuse à travers le grillage 4 et le corps poreux 1 et se répand dans le bain d'acier.When the nose 1 fixed to the end of a blowing lance is introduced into a steel bath and supplied with neutral gas which fills the compression chamber 3, this neutral gas diffuses through the screen 4 and the porous body 1 and spreads in the steel bath.

La fabrication de ce nez poreux est simple. Sur la buselure 2 on soude une rondelle 5 sur laquelle on fixe le grillage 4. La chambre 3 est formée en passant dans l'ouverture de la buselure 2, un corps cylindrique en bois ayant le diamètre voulu pour la chambre 3 et qui dépasse la rondelle 5 d'une longueur égale à la longueur voulue pour ladite chambre de compression. Ensuite on coule le béton poreux devant former le corps 1, puis on retire le corps en bois. Sur la buselure 2 est avantageusement soudée une pièce cylindrique 6 servant d'élément d'ancrage pour fixer plus fermement le béton poreux.Making this porous nose is simple. On the nozzle 2, a washer 5 is welded onto which the screen 4 is fixed. The chamber 3 is formed by passing through the opening of the nozzle 2, a cylindrical wooden body having the desired diameter for the chamber 3 and which exceeds the washer 5 of a length equal to the desired length for said compression chamber. Then pour the porous concrete to form the body 1, then remove the wooden body. On the nozzle 2 is advantageously welded a cylindrical piece 6 serving as an anchoring element for more firmly fixing the porous concrete.

La face extérieure supérieure du corps du nez est avantageusement pourvue d'une chicane annulaire 7 pour éviter la pénétration du bain liquide le long de la jointure du nez avec la buselure 2.The upper external face of the nose body is advantageously provided with an annular baffle 7 to avoid the penetration of the liquid bath along the joint of the nose with the nozzle 2.

Claims (2)

1. Porous tip for an injection lance for stirring steel by injection, comprising a body of solid porous material and a bushing partially embedded in the body, said bushing having means for attachment to the end of a blowing lance, said body being formed with a central cavity which is in communication with the bushing for receiving an inert gas from the lance, characterized by the central cavity (3) being a cylindrical cavity which extend over a major portion of the height of said body (1) of porous material, and by a large-mesh grill (4) which is embedded in the porous material of the body (1), said grill (4) having a cylindrical portion which concentrically encloses a major portion of the central cavity (3) and terminates in an end wall disposed in alignment with the end aperture of the central cylindrical cavity (3), said grill (4) being welded to a metal ring (5) secured to the end of the bushing (2).
2. Porous tip according to claim 1, characterized by comprising at least an anchoring member (6) embedded in the porous material of the body (1), said anchoring member being welded to the bushing (2), said anchoring member having a cylindrical shape which concentrically encloses the large-mesh grill (4).
EP83870064A 1982-06-25 1983-06-22 Porous tip for an injection lance for stirring steel by injection Expired EP0099348B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83870064T ATE28478T1 (en) 1982-06-25 1983-06-22 POROUS SUBMERSIBLE LANCE HEAD FOR BLOWING STEEL.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
BE0/208450A BE893651A (en) 1982-06-25 1982-06-25 POROUS NOSE FOR STEEL BALLING
BE208450 1982-06-25

Publications (2)

Publication Number Publication Date
EP0099348A1 EP0099348A1 (en) 1984-01-25
EP0099348B1 true EP0099348B1 (en) 1987-07-22

Family

ID=3843540

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83870064A Expired EP0099348B1 (en) 1982-06-25 1983-06-22 Porous tip for an injection lance for stirring steel by injection

Country Status (10)

Country Link
US (1) US4492365A (en)
EP (1) EP0099348B1 (en)
JP (1) JPS5910464A (en)
AT (1) ATE28478T1 (en)
BE (1) BE893651A (en)
BR (1) BR8303391A (en)
CA (1) CA1207144A (en)
DE (1) DE3372639D1 (en)
ES (1) ES285245Y (en)
ZA (1) ZA834666B (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3373680D1 (en) * 1982-12-17 1987-10-22 Rene Desaar Porous head for a gas injection lance
EP0336050A1 (en) * 1988-04-08 1989-10-11 RECHERCHES ET DEVELOPPEMENTS DESAAR, société anonyme Injection or blow lance
FR2650520A1 (en) * 1989-08-03 1991-02-08 Vesuvius France Sa KETTLE FOR REGULATING THE FLOW OF A LIQUID COMPRISING A GAS SUPPLIED FREE SPACE
US7198206B2 (en) * 2004-08-02 2007-04-03 Clear Lam, Inc. Compact gassing lance
WO2008052692A1 (en) * 2006-11-02 2008-05-08 Rockwool International A/S Method and apparatus for the production of mineral fibres
FR2931478B1 (en) * 2008-05-26 2012-08-03 Arkema France PRODUCT FOR PREPARING LACTAMS COMPRISING A PHOTONITROSATION STEP FOLLOWED BY A BECKMANN TRANSPOSITION STEP

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR90233E (en) * 1966-06-27 1967-11-03 Air Liquide Improvement in injectors, nozzles and burners for metallurgical furnaces
US3503597A (en) * 1967-02-20 1970-03-31 Kessler Harry Harvey Metal treating device
US3565412A (en) * 1968-12-03 1971-02-23 Dresser Ind Device for stirring molten metal
US3610602A (en) * 1969-10-14 1971-10-05 United States Steel Corp Gas-permeable refractory plug and method
GB1374586A (en) * 1971-10-08 1974-11-20 British Aluminium Co Ltd Apparatus for introducing gas into liquid metal
LU70375A1 (en) * 1973-07-13 1974-10-17
CA1002722A (en) * 1973-10-29 1977-01-04 Frank E. Carroll Insulated roofing structure and method
US4276331A (en) * 1976-01-26 1981-06-30 Repwell Associates, Inc. Metal-ceramic composite and method for making same
FR2380092A1 (en) * 1977-02-10 1978-09-08 Air Liquide GAS INSUFFLATION ROD IN FUSION METAL
DE2713421C3 (en) * 1977-03-26 1979-12-06 Didier-Werke Ag, 6200 Wiesbaden Use of ceramic fiber material and gas flushing lance for molten metal
BE879036A (en) * 1979-09-27 1980-01-16 Desaar Rene SQUEEGEE FOR BLOWING OR INJECTION LANCE

Also Published As

Publication number Publication date
BR8303391A (en) 1984-02-07
ATE28478T1 (en) 1987-08-15
ZA834666B (en) 1984-04-25
ES285245U (en) 1985-09-01
CA1207144A (en) 1986-07-08
BE893651A (en) 1982-12-27
EP0099348A1 (en) 1984-01-25
ES285245Y (en) 1986-05-01
US4492365A (en) 1985-01-08
DE3372639D1 (en) 1987-08-27
JPS5910464A (en) 1984-01-19

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