US3840062A - Continuous steel casting method - Google Patents

Continuous steel casting method Download PDF

Info

Publication number
US3840062A
US3840062A US00745728A US74572868A US3840062A US 3840062 A US3840062 A US 3840062A US 00745728 A US00745728 A US 00745728A US 74572868 A US74572868 A US 74572868A US 3840062 A US3840062 A US 3840062A
Authority
US
United States
Prior art keywords
tundish
steel
mold
molten steel
oxygen
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 - Lifetime
Application number
US00745728A
Other languages
English (en)
Inventor
M Kenney
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to US00745728A priority Critical patent/US3840062A/en
Priority to GB05520/69A priority patent/GB1267942A/en
Priority to FR6915702A priority patent/FR2013162B1/fr
Priority to ES368879A priority patent/ES368879A1/es
Priority to DE19691936336 priority patent/DE1936336A1/de
Application granted granted Critical
Publication of US3840062A publication Critical patent/US3840062A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/10—Supplying or treating molten metal
    • B22D11/106—Shielding the molten jet

Definitions

  • the methods used to control the oxygen content of continuously cast steel include the usual chemical additions to the furnace and the ladle (i.e., the addition of silicon and/or aluminum to the molten steel) and the use of means to prevent steel-air contact, particularly in the teeming stream from ladle to tundish and in the stream between tundish and mold.
  • the theory underlying these proposals is that prevention of steel-air contact will exclude oxygen pick-up from the atmosphere and allow the ordinary chemical methods of deoxidation to reduce the oxygen content of the steel to such a low value as minimizes the presence of nonmetallic inclusions.
  • This invention is directed to method and apparatus for continuously casting steel, in which method the formation of oxides due to the inevitable presence of oxygen in solution is controlled so that the oxides predominately are present in the cast steel in the form of widely dispersed inclusions of small size.
  • the process involves the use of a tundish into which the molten steel is teemed from a suitable ladle, whereafter the molten steel is directed in one or more streams to a conventional continuous casting mold or molds.
  • Chemical deoxidation of the steel is effected by ladle addition and the oxides formed by such chemical deoxidation in the tundish, as well as oxides carried over from the ladle largely are separated out in the form of slag floating on the surface of the molten steel in the tundish.
  • the tundish-to-mold stream is protected by a gaseous envelope to:
  • substantially all of the oxide inclusions in the continuously cast steel will be less than about 20 microns in size and well dispersed whereby the quality of the steel materially is improved.
  • these effects are accomplished by enclosing the tundish-to-mold stream within a flexible, porous sleeve, into which high purity argon gas is introduced under pressure sufficient to cause a continuous flow of the inert gas which constantly flushes the inert atmosphere and thereby removes oxygen, carbon monoxide and gaseous compounds which may contain oxygen from the inert atmosphere, whereby to stimulate and continuously maintain the atmosphere in condition to favor the diffusion of oxygen and gaseous compounds containing oxygen into such atmosphere.
  • I effect this deoxidation and oxygen exclusion of the tundish-to-mold stream by enclosing the stream in a high purity argon atmosphere while continuously changing the atmosphere so that at all times the argon possesses substantially zero partial pressure of oxygen and oxygen-containing gas.
  • the oxides which do form in the solidifying steel are substantially zero partial pressure of oxygen and oxygen-containing gas.
  • FIG. 1 is a vertical section taken through the apparatus for practicing the continuous casting process according to the present invention
  • FIG. 2 is an enlarged section taken through the shroud which encloses the tundish-to-mold stream;
  • FIG. 3 is a section on reduced scale taken along the plane of section line 3-3 in FIG. 2 and showing the cutoff valve device;
  • FIG. 4 is an enlarged transverse section taken along the plane of section line 44 in FIG. 3.
  • the reference character indicates in general a ladle, only the lower portion of which is shown in FIG. 1 and which will be understood to contain molten steel 12 obtained by furnace processing.
  • the ladle is provided with a suitable nozzle or orifice 14 in its bottom and a conventional stopper rod (not shown) is utilized in conjunction therewith to control the flow of steel from the ladle 10 to the underlying tundish 16.
  • the tundish is provided with a pair of nozzle or orifice portions 18 and 20 for delivering the molten steel to the reciprocatory open ended molds 22 and 24.
  • the molds 22 and 24 are of entirely conventional construction as used in the continuous casting industry and are provided with the usual mechanism (not shown) for effecting vertical reciprocatory motion of these molds continuously to follow and then strip from the billets 26 and 28 formed.
  • each valve plate assembly 32 indicated generally by the reference character 32 and the upper faces 34 of the molds 22 and 24 form seats for the collars 36.
  • the lower face 37 of each valve plate assembly 32 forms a seat for the upper collar 38, the two collars 36 and 38 being provided with flanges 40 and 41 which form seats for and are urged apart by the compression spring 42 and interposed between the collars and their respective seating surfaces 34 and 37 are packing or sealing rings 43 and 44 received in suitable grooves in the collars and adapted, under the action of the spring 42, to effect seals at these points.
  • each spring 42 Enclosed within each spring 42 is a porous sleeve 45 having its opposite ends clamped upon the collars 38 and 36 by suitable bands 46 and 47, it being understood that the sleeves 45 are of sufficient length to accommodate for the maximum extension between the molds 22 and 24 and the tundish 16.
  • the valve plate assembly 32 includes a main body portion 50 provided in its upper surface with a slot 52 receiving the cutoff plate member 54.
  • the main body portion 50 of the valve may be of circular profile presenting a relatively large central opening 58 in register with the tundish nozzle 18 whereas the plate 54 is adapted to be moved between covering and uncovering relation to the tundish nozzle 18.
  • the plate 54 is provided with a graphite insert 60 which bears against the bottom surface of the tundish, the insert being provided to prevent welding of the plate 54 to the tundish when the plate is moved into covering relation to the tundish nozzle.
  • Each of the collars 36 is provided with inert gas inlet means which, as can be seen in FIG. 2, may comprise a tube 62 suitably anchored as by the nuts 64 and terminating in a cross tube portion 66 which is closed at its opposite ends 68 and 70 and provided in its lateral side faces with openings 72 to admit the inert gas into the enclosure 74 formed by the porous sleeve 45.
  • Each sleeve 45 is formed of suitable material such as a woven asbestos material having sufficient refractory properties to withstand the heat of its environment and yet having suitable porosity to allow leakage of the inert gas therethrough.
  • the sleeve 45 is of course flexible to accommodate for the vertical reciprocatory motion of the molds 22 and 24.
  • the inert gas preferably high purity argon, is introduced into the enclosures 74 under sufficient pressure to assure a leakage or bleed-off rate of the inert gas from the enclosures 74 which is effective to change and flush the inert gas atmospheres in the enclosures 74 so as to maintain the atmosphere substantially free of oxygen or oxygen-containing gas whereby to favor deoxidation of the tundish-to-mold stream 76.
  • the bleed rate of the inert gas is in the order of 23.44 cubic feet per minute while casting the two, four inch square, billets 26 and 28 (in the order of 48 cubic feet per ton of steel) and typically an internal pressure within each enclosure 74 of about one and one-half pounds per square inch gauge is sufficient to assure such leakage rates.
  • a suitable pressure regulating valve and pressure gauge, not shown, are provided to allow the operator to control the bleed rate.
  • the tundish construction is of entirely conventional nature except for the provision of a pair of dams and 82 upstanding from the bottom walls and extending between the opposite side walls of the tundish. These dams are placed so as to trap the ladle-to-tundish stream 84 therebetween and cause the incoming molten metal to flow upwardly toward the surface 86 of the tundish reservoir before passing downwardly to the nozzles 18 and 20.
  • the surface 86 is of course maintained at a level higher than the dams and means may be provided, not shown, automatically to control the ladle-to-tundish flow for maintaining a fixed metallo static head in the tundish.
  • the dams 80 and 82 are provided to enhance the natural separating effect of the tundish by aiding nonmetallic inclusions in the molten steel in finding their way to the surface 86 whereat they may remain as slag, thereby preventing carry-over into the molds.
  • Calcium and/or silicon are used in the ladle as a deoxidizing agent and the agent preferably is used in the amount of about 5 pounds per ton of steel, sufficient to establish an oxygen content in the tundish of about 60-190 PPM.
  • Thedams 80 and 82 help in assuring that the oxides formed by the aforementioned deoxidizing agents find their way to and remain as slag on the surface 86 of the tundish reservoir so that slag carry-over is also minimized.
  • the depth of the tundish reservoir may be about 17 inches using two 11/16 inch diameter nozzles 18 and 20 to form 4 inch square billets 26 and 28.
  • the tundish-to-mold streams 76 are about inches in length and the casting time for a 22 ton heat is approximately 45 minutes.
  • the steel With the above conditions prevailing, using high pu rity argon gas supplied from a suitable source at a pressure of about 1.5 PSIG and at a through-rate of about 48 cubic feet per ton of steel, the steelwill be characterized by the substantial absence of nonmetallic inclusions larger than about microns and may be produced on a quantity and repetitive basis.
  • the nonmetallic inclusions which are present in the steel are mainly in the form of extremely fine and widely dispersed oxides such as manganese, silicon, aluminum and calcium oxides.
  • this invention in-' volves simultaneously the protection and deoxidation of the tundish-to-mold stream by enclosing the same in an inert atmosphere and changing the atmosphere at a rate continuously to effect deoxidation of the stream.
  • the continuous changing of the inert atmosphere is believed to so favor the diffusion of oxygen and oxygen containing gas from the stream to the atmosphere as inhibits the formation of oxides in the steel except as is incidental to the cooling and freezing of the steel in the mold, whereat they may form as well dispersed and very small inclusions in the steel.
  • any inert atmosphere having substantially zero pressure of oxygen and carbon monoxide will, if changed at a rate to retain such substantially zero partial pressures, so favors the deoxidation of the steel as to accomplish the desired result. Accordingly, other and different inert atmospheres, rather than argon as specifically disclosed, may be used.
  • step (e) continuously maintaining the flow of gas of step (e) during casting at a rate sufficient continuously not only to exclude and to remove oxygen and gasses containing oxygen from said enclosure but also to deoxidize the tundish-to-mold stream and thereby constrain nonmetallic inclusions formed in the solidified steel in the mold to be well dispersed and of sizes less than about 20 microns while reducing the oxygen content of step (b) and obtain an oxygen content in the solidified steel which is within the range of about 40 to about parts per million.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Continuous Casting (AREA)
US00745728A 1968-07-18 1968-07-18 Continuous steel casting method Expired - Lifetime US3840062A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US00745728A US3840062A (en) 1968-07-18 1968-07-18 Continuous steel casting method
GB05520/69A GB1267942A (en) 1968-07-18 1969-03-25 Continuous steel casting method
FR6915702A FR2013162B1 (cs) 1968-07-18 1969-05-14
ES368879A ES368879A1 (es) 1968-07-18 1969-06-27 Un metodo para moldear de manera continua acero de alta ca-lidad.
DE19691936336 DE1936336A1 (de) 1968-07-18 1969-07-17 Verfahren zum kontinuierlichen Giessen eines hochqualitativen Stahls

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00745728A US3840062A (en) 1968-07-18 1968-07-18 Continuous steel casting method

Publications (1)

Publication Number Publication Date
US3840062A true US3840062A (en) 1974-10-08

Family

ID=24997988

Family Applications (1)

Application Number Title Priority Date Filing Date
US00745728A Expired - Lifetime US3840062A (en) 1968-07-18 1968-07-18 Continuous steel casting method

Country Status (5)

Country Link
US (1) US3840062A (cs)
DE (1) DE1936336A1 (cs)
ES (1) ES368879A1 (cs)
FR (1) FR2013162B1 (cs)
GB (1) GB1267942A (cs)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4042229A (en) * 1975-06-17 1977-08-16 Foseco Trading A.G. Tundish with weirs
FR2459094A2 (fr) * 1979-06-21 1981-01-09 Foseco Trading Ag Repartiteur a double garnissage de matiere refractaire pour la coulee de metaux
US4369831A (en) * 1976-06-10 1983-01-25 Sumitomo Electric Industries, Ltd. Protector for molten metal casting stream
US4591135A (en) * 1984-08-15 1986-05-27 Inland Steel Company Fluid flow control structure for tundish
US4653733A (en) * 1984-10-03 1987-03-31 Inland Steel Company Tundish with fluid flow control structure
US4754800A (en) * 1985-12-13 1988-07-05 Inland Steel Company Preventing undissolved alloying ingredient from entering continuous casting mold
WO1999024192A1 (de) * 1997-11-07 1999-05-20 Voest-Alpine Industrieanlagenbau Gmbh Einrichtung zum kontinuierlichen stranggiessen eines metallstranges
WO2000010741A1 (de) * 1998-08-17 2000-03-02 Voest-Alpine Industrieanlagenbau Gmbh Verfahren und anlage zur herstellung von warmgewalztem stahlband aus einer stahlschmelze
RU2162768C2 (ru) * 1999-03-02 2001-02-10 Милькин Владимир Петрович Комбинированный бесстопорный промежуточный ковш машины непрерывного литья заготовок для вакуумирования расплава металла в потоке при разливке его по отдельным кристаллизаторам
WO2011036060A1 (de) 2009-09-23 2011-03-31 Siemens Vai Metals Technologies Gmbh Verfahren und vorrichtung zum vergiessen von metallischer schmelze in einer stranggiessmaschine
CN104399920A (zh) * 2014-11-13 2015-03-11 中色奥博特铜铝业有限公司 一种炉头氮气保护装置及氮气保护方法

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AR206969A1 (es) * 1975-06-17 1976-08-31 Foseco Trading Ag Artesa de colada con vertederos
FI793135A7 (fi) * 1978-11-17 1981-01-01 Concast Ag Menetelmä booripitoisen teräksen käsittelemiseksi.
US4995592A (en) * 1988-12-22 1991-02-26 Foseco International Limited Purifying molten metal
US5131635A (en) * 1990-05-29 1992-07-21 Magneco/Metrel, Inc. Impact pad with rising flow surface
US5131573A (en) * 1991-03-22 1992-07-21 Allegheny Ludlum Corporation Method and device for shrouding a stream of molten metal

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2889596A (en) * 1957-02-26 1959-06-09 British Iron Steel Research Casting of metals
US2983973A (en) * 1956-12-20 1961-05-16 Conrad A Parlanti Methods and apparatus for melting and casting metals in a vacuum
US2997384A (en) * 1958-03-28 1961-08-22 Fischer Ag Georg Method of treating molten metal
US3094424A (en) * 1960-08-02 1963-06-18 Babcock & Wilcox Co Sintered refractory material
FR1395648A (fr) * 1964-02-07 1965-04-16 Est Aciers Fins Installation pour la coulée continue de l'acier calmé
CH411245A (fr) * 1965-02-01 1966-04-15 Monnot Charles Procédé et installation pour la coulée continue d'acier en fusion
US3281903A (en) * 1964-02-03 1966-11-01 Walter C Ross Method and apparatus for continuous horizontal casting
US3392009A (en) * 1965-10-23 1968-07-09 Union Carbide Corp Method of producing low carbon, non-aging, deep drawing steel
US3402757A (en) * 1964-11-24 1968-09-24 United Steel Companies Ltd Method for continuous casting of steel through a closed gas filled chamber
US3459537A (en) * 1966-08-25 1969-08-05 United States Steel Corp Continuously cast steel slabs and method of making same
US3465811A (en) * 1965-11-15 1969-09-09 Est Aciers Fins Plants for the continuous casting of steel
US3467167A (en) * 1966-09-19 1969-09-16 Kaiser Ind Corp Process for continuously casting oxidizable metals

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT246942B (de) * 1960-02-04 1966-05-10 Benteler Geb Paderwerk Verfahren und Einrichtung zur Herstelllung von als Halbzeug für die Herstellung von Bandmaterial und/oder Rohren geeigneten Brammen, Knüppeln, Platinen od. dgl. aus metallischen Schmelzen im Stranggußverfahren
FR1473914A (fr) * 1965-11-20 1967-03-24 Kaiser Ind Corp Procédé et appareillage pour la production de lingots à partir d'un métal coulé oxydable

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2983973A (en) * 1956-12-20 1961-05-16 Conrad A Parlanti Methods and apparatus for melting and casting metals in a vacuum
US2889596A (en) * 1957-02-26 1959-06-09 British Iron Steel Research Casting of metals
US2997384A (en) * 1958-03-28 1961-08-22 Fischer Ag Georg Method of treating molten metal
US3094424A (en) * 1960-08-02 1963-06-18 Babcock & Wilcox Co Sintered refractory material
US3281903A (en) * 1964-02-03 1966-11-01 Walter C Ross Method and apparatus for continuous horizontal casting
FR1395648A (fr) * 1964-02-07 1965-04-16 Est Aciers Fins Installation pour la coulée continue de l'acier calmé
US3402757A (en) * 1964-11-24 1968-09-24 United Steel Companies Ltd Method for continuous casting of steel through a closed gas filled chamber
CH411245A (fr) * 1965-02-01 1966-04-15 Monnot Charles Procédé et installation pour la coulée continue d'acier en fusion
US3392009A (en) * 1965-10-23 1968-07-09 Union Carbide Corp Method of producing low carbon, non-aging, deep drawing steel
US3465811A (en) * 1965-11-15 1969-09-09 Est Aciers Fins Plants for the continuous casting of steel
US3459537A (en) * 1966-08-25 1969-08-05 United States Steel Corp Continuously cast steel slabs and method of making same
US3467167A (en) * 1966-09-19 1969-09-16 Kaiser Ind Corp Process for continuously casting oxidizable metals

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4042229A (en) * 1975-06-17 1977-08-16 Foseco Trading A.G. Tundish with weirs
US4369831A (en) * 1976-06-10 1983-01-25 Sumitomo Electric Industries, Ltd. Protector for molten metal casting stream
FR2459094A2 (fr) * 1979-06-21 1981-01-09 Foseco Trading Ag Repartiteur a double garnissage de matiere refractaire pour la coulee de metaux
US4591135A (en) * 1984-08-15 1986-05-27 Inland Steel Company Fluid flow control structure for tundish
US4653733A (en) * 1984-10-03 1987-03-31 Inland Steel Company Tundish with fluid flow control structure
US4754800A (en) * 1985-12-13 1988-07-05 Inland Steel Company Preventing undissolved alloying ingredient from entering continuous casting mold
WO1999024192A1 (de) * 1997-11-07 1999-05-20 Voest-Alpine Industrieanlagenbau Gmbh Einrichtung zum kontinuierlichen stranggiessen eines metallstranges
WO2000010741A1 (de) * 1998-08-17 2000-03-02 Voest-Alpine Industrieanlagenbau Gmbh Verfahren und anlage zur herstellung von warmgewalztem stahlband aus einer stahlschmelze
RU2162768C2 (ru) * 1999-03-02 2001-02-10 Милькин Владимир Петрович Комбинированный бесстопорный промежуточный ковш машины непрерывного литья заготовок для вакуумирования расплава металла в потоке при разливке его по отдельным кристаллизаторам
WO2011036060A1 (de) 2009-09-23 2011-03-31 Siemens Vai Metals Technologies Gmbh Verfahren und vorrichtung zum vergiessen von metallischer schmelze in einer stranggiessmaschine
CN104399920A (zh) * 2014-11-13 2015-03-11 中色奥博特铜铝业有限公司 一种炉头氮气保护装置及氮气保护方法

Also Published As

Publication number Publication date
DE1936336A1 (de) 1970-08-27
GB1267942A (en) 1972-03-22
FR2013162B1 (cs) 1974-05-03
FR2013162A1 (cs) 1970-03-27
ES368879A1 (es) 1971-05-16

Similar Documents

Publication Publication Date Title
US3840062A (en) Continuous steel casting method
JPH0142787B2 (cs)
DE1219183B (de) Verfahren zur Verhinderung von Kernfehlern in Gussbloecken
US3888294A (en) Method of continuously casting steel
US4858674A (en) Casting aluminium alloys
US3771584A (en) Method for continuously casting steel billet strands to minimize the porosity and chemical segregation along the center line of the strand
US3776295A (en) Method of continuous rotary casting of metal utilizing a liquefied gas to facilitate solidification
CA1328978C (en) Method for continuous casting of an aluminum-lithium alloy
ES8602460A1 (es) Un metodo para proporcionar una envuelta de gas protectora alrededor del acero, para evitar la oxidacion.
FR2328536A1 (fr) Dispositif pour proteger un jet de metal liquide lors de la coulee
US3935895A (en) Continuous steel casting method
GB1298346A (en) Method and apparatus for shrouding a pouring stream and molten casting surface with a protective gas
KR920000953A (ko) 대기용해에 의한 알루미늄-리튬합금의 제조방법
US3189956A (en) Production of effervescing steel
US3811490A (en) Continuous casting of rimming steel
US3078531A (en) Additives for molten metals
US2450081A (en) Noble gas metallurgy
US3373794A (en) Ferroalloy casting process
US3521695A (en) Method of producing a steel ingot
GB1428204A (en) Methood for adding lead to molten steel in a ladle
JPS5514132A (en) Preventing method for oxygen entry of cast ingot in continuous casting and device thereof
US4615373A (en) Method and an apparatus for manufacturing a hollow steel ingot
US3321006A (en) Methods of treating metal
JPH0847747A (ja) 銅の連続鋳造方法およびその装置
JPS63137544A (ja) 水平連続鋳造法