EP0097561B2 - Procédé et installation de brassage électromagnétique de brames métalliques, notamment d'acier, coulées en continu - Google Patents

Procédé et installation de brassage électromagnétique de brames métalliques, notamment d'acier, coulées en continu Download PDF

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Publication number
EP0097561B2
EP0097561B2 EP83401148A EP83401148A EP0097561B2 EP 0097561 B2 EP0097561 B2 EP 0097561B2 EP 83401148 A EP83401148 A EP 83401148A EP 83401148 A EP83401148 A EP 83401148A EP 0097561 B2 EP0097561 B2 EP 0097561B2
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EP
European Patent Office
Prior art keywords
mold
strand
slab
inductors
liquid metal
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
EP83401148A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0097561A1 (fr
EP0097561B1 (fr
Inventor
Jean-Pierre Birat
Patrick Neu
Denis Senaneuch
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.)
Rotelec SA
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Rotelec SA
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Publication date
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Application filed by Rotelec SA filed Critical Rotelec SA
Priority to AT83401148T priority Critical patent/ATE28586T1/de
Publication of EP0097561A1 publication Critical patent/EP0097561A1/fr
Application granted granted Critical
Publication of EP0097561B1 publication Critical patent/EP0097561B1/fr
Publication of EP0097561B2 publication Critical patent/EP0097561B2/fr
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    • 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
    • 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
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/122—Accessories for subsequent treating or working cast stock in situ using magnetic fields

Definitions

  • the present invention relates to the electromagnetic stirring of metallic slabs, in particular of steel, continuously cast. It relates more precisely to the electromagnetic stirring operations of the molten metal in the secondary cooling zone of a continuous slab casting machine.
  • the electromagnetic stirring operations consist, as is known, of subjecting the cast product to one or more mobile magnetic fields, sliding in a determined direction, and whose action on the liquid metal is then manifested by a drive of the latter identical, in direction and direction, to the displacement of the magnetic field.
  • the mobile magnetic field is generally created by a polyphase static inductor preferably placed in the immediate vicinity of the cast product and which can have different designs: for example a monobloc inductor, similar to a linear induction motor stator, placed either behind the rollers of holding and guiding the slab during casting, either as a replacement for one or more of these rollers (French patent no. 2,068,803, German patent no. 2,401,145), or even in spaces made available between two consecutive rolls (French patent n ° 2 187 468). It has also been proposed an inductor of cylindrical structure introduced into the interior of one or more rollers, made tubular for this purpose (English Patent No. 1,405,312).
  • the question which then arises, and to which the present invention aims to answer, consists in knowing whether there is an optimal type of stirring making it possible to obtain, together with a very wide central equiaxial zone, a level of the lowest possible macro-segregation, and in any case significantly more reduced than that obtained by the usual technique of electromagnetic stirring.
  • Another aim is to achieve the above-mentioned result with a minimum of mixing inducers.
  • the invention relates to a method of electromagnetic stirring of metallic slabs, in particular of steel, continuously cast, according to which, in the part of the liquid well located downstream of the mold in the direction of extraction of the slab, the latter is subjected to at least one mobile magnetic field, sliding along the width of the slab and creating a movement of entrainment of the molten metal, process characterized in that, in order to stir the molten metal on the portion of the cast product lying between 3 to 4 meters approximately under the free surface of the metal in the mold and approximately 2 to 3 meters from the bottom of the solidification well, a plurality of sliding magnetic fields produced by electromagnetic inductors are made to act.
  • the inductor closest to the mold is located at approximately 5 to 7 m below the free surface of the liquid metal and the inductor closest to the bottom of the solidification well is located at about 4 to 6 m from this bottom, and in that the inductors are adjusted so that the magnetic field created by any inductor slides in a direction opposite to that of the magnetic fields created by the nearest neighboring inductors.
  • these are arranged in a staggered configuration on either side of the two large faces of the slab.
  • the electromagnetic inductor closest to the ingot mold is placed on the upper surface of the slab, that is to say facing the large face placed opposite the center of curvature of the machine. continuous casting.
  • the invention consists, in its fundamental features, in distributing the electromagnetic stirring energy transmitted to the cast metal over the major part of the metallurgical height so as to create convective movements which s 'establish in almost all of the solidification wells.
  • the portion of the metallurgical height to be subjected to electromagnetic stirring in accordance with the invention lies between an upper limit, approximately 3 to 4 meters below the free surface of the metal in the mold, and a lower limit which can be situated approximately 2 or 3 meters from the closing point of the solidification well.
  • the action of the magnetic field closest to the ingot mold is located approximately 5 to 7 meters below the free surface of the liquid metal, and the action of the last magnetic field is located near the bottom of the well. solidification, at a distance of approximately 4 to 5 meters above said bottom.
  • the average distance separating a direct drive zone from a recirculation zone depends primarily on the electromagnetic force to which the liquid metal is subjected, that is to say essentially on the intensity of the magnetic field. acting on the metal, since the sliding speed of the field (ie frequency of the electric current in the inductor) is necessarily low, around 1 to 5 Hz approximately, to limit the weakening of the field between the active surface of the inductor and liquid metal.
  • electromagnetic inductors compatible with a continuous slab casting installation under normal operating conditions make it possible to deliver magnetic fields which are strong enough for the difference between the direct entrainment zone of the liquid metal and the recirculation zone is around 2 meters approximately, or even beyond.
  • the depth at which these different negative segregation zones are located in the product relative to its surface depends on the local operating conditions of the casting machine and in particular on the initial overheating of the metal feeding the ingot mold, the extraction speed slab and speed of solidification of the product, that is to say the adjustment of the cooling system. Knowledge of these different parameters therefore makes it possible to easily link the depth of localization of negative segregation zones to the levels on the metallurgical height where the direct circulation and recirculation movements of liquid metal occur under the action of magnetic fields.
  • the upper and lower limit levels defining the portion of the metallurgical height subjected to stirring in accordance with the invention make it possible to approach fairly finely, in each case, the upper and lower limit levels defining the portion of the metallurgical height subjected to stirring in accordance with the invention.
  • this can range from approximately 0.7 meters / minute to more than 3 meters / minute, this is that is to say vary in a ratio of 1 to 5 between different installations, or pouring different grades of steel.
  • FIGS. 1 and 2 show schematically a mold 1, a nozzle 2 supplying the mold with liquid metal. the slab 3 during casting and having a solidified outer layer 4 and a core in the liquid state 5.
  • the line drawn at 6 defines the closure of the solidification well by joining the increasing solidification fronts on the large faces of the product.
  • the metallurgical height "H" that is to say the distance separating the surface of the liquid metal 7 in the mold from the closure 6 of the solidification well, can be read directly in meters in FIG. 1 thanks to the marks placed on the small left side of the slab.
  • the regions of direct action of the sliding magnetic fields have been represented by the two hatched zones 9 and 10.
  • zones define the regions for direct entrainment of the liquid metal whose lines of current have been represented by the loops 13 in thick lines in FIG. 1.
  • the directions of sliding of the magnetic fields acting along the width of the slab are indicated by arrows on the left of the direct drive zones 9 and 10 of the Figure 1 and by the conventional symbols in fig. 2.
  • the minimum configuration representative of the distribution of the action of the magnetic field over the metallurgical height is characterized here, as can be seen, by the installation of a first pair of brewer rollers 11,11 'on the upper surface of the slab, downstream of the ingot mold, at an average distance of 6 meters from the free surface 7 of the cast metal, and a second pair of rollers 12, 12 'offset downward relative to the pair 11, 11' d 'an average distance of 1.50 meters. Furthermore, the direction of sliding of the magnetic field created by the pair 11, 11 'is opposite to that created by the pair 12, 12'.
  • this movement in “butterfly wings comprises, as can be seen, a central body 13 with relatively intense circulation because it is generated by the combined effect of the two direct drive zones 9 and 10 and, on both sides. other of this central body 13, recirculation regions 14, 15, which flourish respectively upwards and downwards up to the levels, on the metallurgical height, of 3.5 meters and 10 meters approximately.
  • the metallographic analyzes carried out show that the slabs poured and stirred continuously in the manner which has just been described have a very large equiaxed solidification zone which is already initiated at a skin depth corresponding to the level, over the metallurgical height, about 3.5 meters.
  • these analyzes also show that the core of the slabs is practically free of macrosegregation phenomena.
  • the negative segregation ring corresponding to the low recirculation region 15 is not observable on the metallographic section, since we are located at this level in a region where the proportion of solid in the liquid is very important and therefore forms a rigid skeleton and where, consequently, the sweeping of the solidification front by the forced convection movements of the metal tal liquid, responsible for the formation of a negative segregation zone, no longer operates in this regard significantly.
  • the staggered arrangement of the mixing inductors defining the direct drive zones is justified if the number of available inductors is limited. If not, it is entirely possible to couple the inductors one next to the other at the level of the direct drive zones, the important thing in this case being of course that the magnetic fields created by the inductors paired at the level of a specific direct training area slides in the same direction.
  • the inducing units paired on the same face of the slab such as 11, 11 ′ to 12, 12 ′ and / or paired at the same level on the two faces opposite, constitute one and the same inductor, because they are intended to produce one and the same direct entrainment zone of the liquid metal.
  • the direction of sliding of the magnetic field is uniform for these inducing units.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Braking Arrangements (AREA)
  • Dental Prosthetics (AREA)
  • Accessories For Mixers (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)
EP83401148A 1982-06-18 1983-06-07 Procédé et installation de brassage électromagnétique de brames métalliques, notamment d'acier, coulées en continu Expired - Lifetime EP0097561B2 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83401148T ATE28586T1 (de) 1982-06-18 1983-06-07 Verfahren und vorrichtung zum elektromagnetischen ruehren stranggegossener brammen, insbesondere aus stahl.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8210844A FR2528739B1 (fr) 1982-06-18 1982-06-18 Procede et installation de brassage electromagnetique de brames metalliques, notamment d'acier, coulees en continu
FR8210844 1982-06-18

Publications (3)

Publication Number Publication Date
EP0097561A1 EP0097561A1 (fr) 1984-01-04
EP0097561B1 EP0097561B1 (fr) 1987-07-29
EP0097561B2 true EP0097561B2 (fr) 1993-12-08

Family

ID=9275241

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83401148A Expired - Lifetime EP0097561B2 (fr) 1982-06-18 1983-06-07 Procédé et installation de brassage électromagnétique de brames métalliques, notamment d'acier, coulées en continu

Country Status (13)

Country Link
US (1) US4562879A (enrdf_load_stackoverflow)
EP (1) EP0097561B2 (enrdf_load_stackoverflow)
JP (1) JPS5954451A (enrdf_load_stackoverflow)
KR (1) KR910006065B1 (enrdf_load_stackoverflow)
AT (1) ATE28586T1 (enrdf_load_stackoverflow)
AU (1) AU569037B2 (enrdf_load_stackoverflow)
BR (1) BR8303222A (enrdf_load_stackoverflow)
CA (1) CA1208878A (enrdf_load_stackoverflow)
DE (1) DE3372722D1 (enrdf_load_stackoverflow)
ES (1) ES8501266A1 (enrdf_load_stackoverflow)
FR (1) FR2528739B1 (enrdf_load_stackoverflow)
MX (1) MX159768A (enrdf_load_stackoverflow)
ZA (1) ZA834477B (enrdf_load_stackoverflow)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008003838A1 (fr) * 2006-07-07 2008-01-10 Rotelec Procede de coulee continue de produits metalliques plats a brassage electromagnetique et installation de mise en œuvre

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3372958B2 (ja) * 1997-12-08 2003-02-04 新日本製鐵株式会社 溶融金属の鋳造方法およびその装置並びに鋳片
JP2002137191A (ja) * 2000-10-30 2002-05-14 Eastern Giken Kk カートン装着用の切断刃
RU2409448C2 (ru) * 2006-07-07 2011-01-20 Ротелек Способ непрерывного литья плоских металлических изделий с электромагнитным перемешиванием и установка для его осуществления
FR2957829B1 (fr) * 2010-03-23 2012-11-09 Rotelec Sa Rouleau brasseur pour machine de coulee continu de brames
CN112045157A (zh) * 2020-07-24 2020-12-08 邯郸钢铁集团有限责任公司 一种低合金高强度耐磨钢板坯的生产方法
CN114682743B (zh) * 2021-12-29 2023-06-13 北京科技大学 一种金属熔体电磁搅拌装置

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1962341B2 (de) * 1969-12-12 1971-06-24 Aeg Elotherm Gmbh Anordnung einer mehrphasigen elektromagnetischen wicklung am strangfuehrungsgeruest einer stranggiessanlage
US3882923A (en) * 1972-06-08 1975-05-13 Siderurgie Fse Inst Rech Apparatus for magnetic stirring of continuous castings
JPS5236492B2 (enrdf_load_stackoverflow) * 1972-12-20 1977-09-16
US4030534A (en) * 1973-04-18 1977-06-21 Nippon Steel Corporation Apparatus for continuous casting using linear magnetic field for core agitation
JPS529170A (en) * 1975-07-14 1977-01-24 Ishikawajima Harima Heavy Ind Co Ltd Grading apparatus
DE2810491A1 (de) * 1978-03-08 1979-09-20 Aeg Elotherm Gmbh Verfahren zur beeinflussung der erstarrung einer schmelze waehrend des stranggiessens
FR2437900A1 (fr) * 1978-10-05 1980-04-30 Siderurgie Fse Inst Rech Procede de coulee continue des metaux avec brassage dans la zone du refroidissement secondaire
JPS5592260A (en) * 1978-12-29 1980-07-12 Sumitomo Electric Ind Ltd Steel manufactured by continuous casting method and production thereof
DE2912539A1 (de) * 1979-03-29 1980-10-09 Licentia Gmbh Vorrichtung zum elektrodynamischen ruehren des sumpfes in einer stranggegossenen erstarrenden metallbramme
FR2494607A1 (fr) * 1980-11-25 1982-05-28 Cem Comp Electro Mec Inducteur a champ glissant et a flux oriente pour rouleau- brasseur de coulee continue de brames

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008003838A1 (fr) * 2006-07-07 2008-01-10 Rotelec Procede de coulee continue de produits metalliques plats a brassage electromagnetique et installation de mise en œuvre

Also Published As

Publication number Publication date
KR910006065B1 (ko) 1991-08-12
AU1579783A (en) 1983-12-22
DE3372722D1 (en) 1987-09-03
EP0097561A1 (fr) 1984-01-04
FR2528739A1 (fr) 1983-12-23
ES523383A0 (es) 1984-11-16
JPS5954451A (ja) 1984-03-29
ES8501266A1 (es) 1984-11-16
ATE28586T1 (de) 1987-08-15
JPH048134B2 (enrdf_load_stackoverflow) 1992-02-14
FR2528739B1 (fr) 1985-08-02
MX159768A (es) 1989-08-17
BR8303222A (pt) 1984-01-31
EP0097561B1 (fr) 1987-07-29
ZA834477B (en) 1984-03-28
AU569037B2 (en) 1988-01-21
KR840005029A (ko) 1984-11-03
US4562879A (en) 1986-01-07
CA1208878A (fr) 1986-08-05

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