EP0286960A1 - Vorrichtung zum elektromagnetischen Rühren von flüssigem Metall in einer Stranggusslinie - Google Patents

Vorrichtung zum elektromagnetischen Rühren von flüssigem Metall in einer Stranggusslinie Download PDF

Info

Publication number: EP0286960A1
Authority: EP; European Patent Office
Prior art keywords: inductor; carriage; axis; cast product; parts
Prior art date: 1987-04-13
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.): Granted

Application number

EP88105460A

Other languages

English (en)

French (fr)

Other versions

EP0286960B1 (de

Inventor

Marie Claude Nove

Michel Kouyoumdjian

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

Original Assignee

Alstom SA

GEC Alsthom SA

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.)

1987-04-13

Filing date

1988-04-06

Publication date

1988-10-19

1988-04-06 Application filed by Alstom SA, GEC Alsthom SA filed Critical Alstom SA

1988-04-06 Priority to AT88105460T priority Critical patent/ATE67436T1/de

1988-10-19 Publication of EP0286960A1 publication Critical patent/EP0286960A1/de

1991-09-18 Application granted granted Critical

1991-09-18 Publication of EP0286960B1 publication Critical patent/EP0286960B1/de

2008-04-06 Anticipated expiration legal-status Critical

Status Expired - Lifetime legal-status Critical Current

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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
- B22D11/12—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 obtaining a long metallurgical product by continuous casting. It relates more particularly to an electromagnetic equipment usable for stirring the metal which remains liquid within the product during its progression along the casting line. It is known that during this progression, the cast product cools and solidifies little by little from its surface and that a stirring of the metal remaining liquid is conventionally carried out because the setting in motion of this metal improves the quality final metallurgical of the cast product. If this setting in motion is caused by an electromagnetic induction, it is called “electromagnetic stirring”. Such stirring is used industrially at one or more levels of the continuous casting line: at the level of the mold (called level M by specialists), below the mold in the so-called secondary cooling zone (level S), and at the bottom of the solidification well (level F).
stirring can be obtained by means of a mobile magnetic field, either rotating or sliding, which penetrates the cast product.
rotary stirring is well suited for round, square or slightly rectangular products, that is to say close in cross-section to the square shape, which is the the case of billets and blooms.
the rotary inductor is that which makes it possible to achieve the best penetration of the magnetic induction in the heart of the cast product and thus to act effectively on the whole mass of the liquid to be stirred.
linear mixing is well suited for flat products, such as slabs.
Known rotary inductors are always constructed so as to create a magnetic induction passing through the cast product perpendicular to the casting axis, the rotation of the induction around this axis being obtained by supplying the inductor with polyphase currents (generally two-phase in the case of a square and three-phase inductor in the case of a round inductor).
polyphase currents generally two-phase in the case of a square and three-phase inductor in the case of a round inductor.
the inductor completely surrounds the cast product. More precisely, no rotating field inductor has been produced or proposed publicly which does not completely surround the cast product, and it appeared impossible to economically use a rotating field as soon as the configuration of the casting machine continues. , at the level where one intended to carry out the mixing, did not allow the inductor to completely surround the poured product.
a linear inductor was then used which was placed on the most accessible face, or on the only accessible face of the casting line. That is to say that the least efficiency of such an inductor was accepted in the cases where rotary stirring is most effective.
a first solution may be to use several partial inductors, mechanically separated but electrically and magnetically coupled and to arrange them symmetrically with respect to the cast product, so that they produce a rotating field like a single rotary inductor of known type.
such a solution does not always make it possible to resolve all the difficulties encountered for the implantation of a rotating field inductor on a preexisting continuous casting line.
An object of the present invention is to make possible and easy the installation, operation, maintenance and replacement of an inductor device in most cases where the configuration of the continuous casting lines considered seemed to oppose it at the level proposed brewing.
the subject of the present invention is a device for electromagnetic stirring of liquid metal for a continuous casting line, this device being intended to stir, in the vicinity of an ingot mold, the internal liquid mass of a poured metallic product which leaves and descends continuously from this ingot mold along a casting axis, this mass being surrounded by an outer skin, initially thin, of solidified metal, this cast product being surrounded by a guide segment carrying support rollers, this device comprising, to carry out the stirring, an inductor at least partially surrounding at least this cast product and suitable for causing a magnetic field to penetrate therein substantially perpendicular to this axis and rotating around it, this inductor being heavy and comprising at least coils to create this magnetic field, a rigid carcass for holding these coils and cooling circuits, this device also comprising an electrical distribution box for supplying these coils from an external source, - and a water distribution box to supply these cooling circuits, this device being characterized by the fact that said inductor consists of two separable inductor parts disposed substantially
- Said spacing means comprise a hinge guiding a rotation of the two said carcasses around an axis of rotation which is substantially parallel to said casting axis and which is located next to the inductor, at the rear thereof , - And support means carried by said carriage to support each of the two carcasses during a limited rotation around of this axis of rotation so as to allow sometimes to open said inductor on its front side to allow said movements of said carriage carrying this inductor, sometimes to close it at least partially around said cast product when this carriage is in its said position service to stir the liquid metal in this product.
- Said carriage has the shape of a coated U opening forward to allow to engage the two branches of this U on either side of said cast product, each of said carcasses being provided at its lower part d 'A rolling means which, during said opening and closing movements, rolls on a raceway formed on an upper face of one of these branches, to constitute said support means.
- Said electrical distribution and water distribution boxes are arranged at the rear of said inductor.
the axis of a continuous casting line is first substantially vertical and then gradually curves towards a horizontal casting direction passing through intermediate directions, which defines a lower surface side in the concavity of this axis towards this horizontal pouring direction, and an opposite upper surface side, and where a line support structure is arranged on the upper surface side of this line and therefore hinders access thereto on this side, said axis of rotation s 'extends in a said intermediate direction close to the vertical, the direction of movement of said carriage is horizontal to facilitate movement and said front side of the inductor and the carriage look towards said upper surface side.
said inductor in the service position not only surrounds said cast product, but also said guide segment, and the support rollers and their bearings located in the magnetic field are made of non-magnetic austenitic steel, as well as, optionally, the entire segment.
Each of said carcasses is guided and carried by said hinge and said carriage by means of a support.
Said water distribution box is carried by said carriage and connected to the cooling circuits of said inductor parts by flexible pipes and to an external supply by an inlet pipe and a return pipe also flexible.
- Said electrical distribution box is carried by said carriage and supplies each of the two said inductive parts by means of flexible wires and two terminal boxes fixed to each of said inductive parts.
- Said inductor is a bipolar polyphase inductor formed by two half-inductors respectively constituting the two said inductor parts and each contained in a said metal carcass, these two half-inductors being mechanically separable and electrically and magnetically coupled in order to be equivalent in service to a single inductor.
the device further comprises mechanical means for opening, closing and locking in the service position of said supports and said inductive parts.
the device also generally comprises an electrical and hydraulic control panel ensuring the maneuvers and the supply of water and electric current.
the device according to the invention thus comprises two halves of a mechanical assembly articulated around a hinge and provided with operating and feeding means. It can be used with advantage in a very large number of practical cases. It can consist of two mechanically separable half-inductors electrically and magnetically coupled, either completely or almost completely surrounding, after locking, the casting line continues at the level of mixing considered, or arranged on two opposite faces of the line. But it can just as easily be made up of two inductors distinct from the electrical and magnetic points of view, either partially surrounding the continuous casting line, or placed on two of its opposite faces.
the invention is particularly advantageous when it is desired use a rotating field and the configuration of the continuous casting line precludes the installation of a rotating field inductor of known type.
the two half-inductors locked in the service position are practically equivalent to a rotary inductor of known type completely surrounding the continuous casting line at the level considered.
the handling of the inductor parts, their maintenance and their replacement are particularly easy.
FIGS. 1A, 1B and 1C provide a good understanding of the principle of the invention.
the curved axis of a casting line is represented at A.
This axis simultaneously represents the path of the metal product cast which here is a bloom of steel.
This bloom is represented only by this axis. It is formed in an ingot mold 1 of continuous casting from which it flows and which is completed downwards by four series of very close rollers, on each face of the bloom; their roughly square section envelope constitutes the "segment" 2. It is at level S of this segment that the electromagnetic stirring of the liquid part of the product is to be carried out.
the carcasses 3 and 4 containing the two half-inductors as well as their respective supports 5 and 6 are articulated around the rod 7b of a hinge 7 and rest on a carriage 8, movable in horizontal-tal translation, d-shaped 'U.
the laying, around segment 2 at level S, of the two half-inductors is carried out by the mechanical device of the invention in the following manner, passing through the three stages shown in FIGS. 1A, 1B, 1C.
the carriage 8 is pushed by mechanical means towards the segment 2 until it occupies the position shown in FIG. 1C (or in phantom in FIG. 1B); the two halves of the articulated device are then closed, and a locking device is operated opposite the hinge 7.
the inductor consisting of the two half-inductors is then in the operating position at level S.
the carriage 8 rectangular, has a large U-shaped notch 10 of two rolling tracks 27 and 28. It supports: . the two carcasses 3 and 4 of the two half-inductors, by means of their respective supports 5 and 6 which are articulated around the rod 7b of the hinge 7. This rod is fixed on the carriage.
the two carcasses are supported by means of two rollers 29 and 30 rolling on the tracks 27 and 28 and each receiving a yoke not shown, fixed to the base of each of the two carcasses. .
a hydraulic distribution box for cooling the half-inductors a hose 11, connected upstream to the general water network, supplies cooling water to the hydraulic box 12, which distributes it over the two half-inductors through the two lines 13 and 14; the water return is effected by the two pipes 15 and 16, which converge in a second compartment of the hydraulic box 12, and the water is then evacuated by a hose not shown, similar to the hose 11.
the valve water intake, not shown, is controlled from a control console located near the carriage. . an electrical distribution box 17 supplied from an appropriate power equipment, in three-phase current, by four flexible cables including three phase cables such as 18 and a neutral cable such as 18b.
each half-inductor comprises three coils, one per phase, requiring six incoming wires, such as 19, or twelve in all, which start from the box 17. .
two terminal boxes 20 and 21 which respectively supply the half-inductors contained in the carcasses 3 and 4; the entire electrical diagram of the electrical distribution box and the two terminal boxes is given in Figure 4.
the mechanical means 22 and 23 allowing the opening and closing of the two movable parts around the hinge 7.
a gusset welded to each carcass, provided with a rod 31 and 31b and a yoke 32 and 32b ensures all the flexibility desired when operating the screw-nut system 33 and 33b by means of the crank 34 and 34b.
the above is an example of manual opening and closing control. It is also possible to perform these functions either hydraulically or electrically, the control being able to be located either on the trolley or at the control console.
a locking system 24 gives the assembly of the two mobile parts the necessary rigidity and ensures the closure of the magnetic flux despite the very narrow intervals 25 and 26, visible in Figure 5, which remain between the two half-inductors.
the half-inductors completely surround the continuous casting line, that is to say the cast product 27 and the rollers as 28 grouped in segment 2, and produced as well as their bearings in non-magnetic austenitic stainless steel .
Each half-inductor here comprises three coils regularly spaced from each other. Each of them is in phase with the coil of the other half-inductor which is diametrically opposite to it. Let B1 and B1b be the coils of phase 1, B2 and B2b the coils of phase 2, B3 and B3b the coils of phase 3 ( Figure 5).
FIG. 4 is an electrical diagram of the assembly inside the distribution box 17 and the two terminal boxes 20 and 21.
the flexible supply cables are marked Ph. 1, Ph.2, Ph.3, and N, respectively for phases 1, 2, 3 and for the neutral, and are connected to terminals 18 and 18b of the carriage 8.
the terminal U1 of the terminal box 21 is supplied by phase 1, and it is connected to the coil B1, the other end of which is connected to the terminal U11 of the box 21.
the terminal U11 is connected to the terminal U22 of the other terminal box 20.
the terminal U22 is connected to the coil B1b of the other half-inductor, diametrically opposite to B1 .
the other end of the coil B1b is connected to the terminal X of the box 20.
the two coils B1 and B1b are in phase and in series.
phase 2 successively traverses terminal V1 of the terminal box 21, the coil B2 of the half-inductor 4, the terminal V11 of the box 21, the distribution box 17, the terminal B22 of the box 20, the coil B2b of the other half-inductor 3, and the terminal Y of the box 20.
B2 and B2b are indeed in phase and in series.
phase 3 successively traverses the terminal W1 of the box 20, the coil B3b of the half-inductor 3, the terminal W11 of the terminal box 20, the distribution box 17, the terminal W22 of the box 21, the coil B3 of the half-inductor 4 and the terminal Z of the terminal box 21.
the two coils B3 and B3b are in phase and in series.
the three terminals X, Y, Z are connected to each other and to terminal 18b of the carriage 8, itself connected to the cable N.
the mechanical device according to the invention with its electrical distribution box and its two terminal boxes supported by the carriage, is such that the separation into two half-inductors practically does not harm the electromagnetic efficiency of the assembly thus formed.
FIG. 5 is a diagram of the configuration of the magnetic flux at a determined instant of the electromagnetic cycle.
the lines of this flow are shown in thin lines. It turns with the evolution of the power supply cycle.
the intervals 25 and 26 existing between the two magnetic cores are very narrow and only slightly reduce the efficiency of the magnetic flux.

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Engineering & Computer Science (AREA)
Mechanical Engineering (AREA)
Continuous Casting (AREA)
Manufacture Of Alloys Or Alloy Compounds (AREA)

EP88105460A 1987-04-13 1988-04-06 Vorrichtung zum elektromagnetischen Rühren von flüssigem Metall in einer Stranggusslinie Expired - Lifetime EP0286960B1 (de)

Priority Applications (1)

Application Number	Priority Date	Filing Date	Title
AT88105460T ATE67436T1 (de)	1987-04-13	1988-04-06	Vorrichtung zum elektromagnetischen ruehren von fluessigem metall in einer stranggusslinie.

Applications Claiming Priority (2)

Application Number	Priority Date	Filing Date	Title
FR8705202A FR2613647B1 (fr)	1987-04-13	1987-04-13	Dispositif de brassage electromagnetique de metal liquide pour ligne de coulee continue
FR8705202		1987-04-13

Publications (2)

Publication Number	Publication Date
EP0286960A1 true EP0286960A1 (de)	1988-10-19
EP0286960B1 EP0286960B1 (de)	1991-09-18

Family

ID=9350055

Family Applications (1)

Application Number	Title	Priority Date	Filing Date
EP88105460A Expired - Lifetime EP0286960B1 (de)	1987-04-13	1988-04-06	Vorrichtung zum elektromagnetischen Rühren von flüssigem Metall in einer Stranggusslinie

Country Status (7)

Country	Link
US (1)	US4834168A (de)
EP (1)	EP0286960B1 (de)
JP (1)	JPS63268544A (de)
AT (1)	ATE67436T1 (de)
CA (1)	CA1326585C (de)
DE (1)	DE3864880D1 (de)
FR (1)	FR2613647B1 (de)

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
JPH06205Y2 (ja) *	1989-03-17	1994-01-05	吉田工業株式会社	水平連続鋳造装置における二次冷却装置
FR2721148B1 (fr) *	1994-06-10	1996-08-02	Rotelec Sa	Système de raccordement électrique déconnectable pour ensemble mobile.
DE19853189C1 (de) *	1998-11-18	2000-04-13	Frech Oskar Gmbh & Co	Heizeinrichtung für den Hals eines Gießbehälters, insbesondere für eine Warmkammer-Druckgießmaschine
DE10146993A1 (de) *	2001-09-25	2003-04-10	Sms Demag Ag	Elektromagnetische Bremsvorrichtung für die Kokille einer Stranggießanlage
FR2856321B1 (fr) *	2003-06-17	2006-05-26	Usinor	Installation de coulee continue pour une mise en rotation electro-magnetique du metal liquide en transit dans la busette de coulee
FR2894167A1 (fr) *	2005-12-06	2007-06-08	Usinor Sa	Equipement pour la coulee en repartiteur de coulee continue des metaux
US20080164004A1 (en) *	2007-01-08	2008-07-10	Anastasia Kolesnichenko	Method and system of electromagnetic stirring for continuous casting of medium and high carbon steels
JP5142281B2 (ja) *	2008-09-05	2013-02-13	新日鐵住金株式会社	鋳型内溶鋼への電磁攪拌装置
GB201318482D0 (en) *	2013-10-18	2013-12-04	Altek Europ Ltd	Improvements in and relating to apparatus for stirring and methods of stirring
CN103706772A (zh) *	2013-12-20	2014-04-09	鞍钢股份有限公司	一种减缓小铸坯钢水冲击深度装置及方法
KR101934495B1 (ko) *	2014-06-10	2019-01-02	노스이스턴 유니버시티	전자기 스월 노즐 연속주조 방법 및 장치
AT518460B1 (de) *	2016-03-21	2021-07-15	Primetals Technologies Austria GmbH	Einen Metallstrang partiell umgreifende Rührspule
GB201619598D0 (en) *	2016-11-20	2017-01-04	Altek Europe Ltd	Improvements in and relating to apparatus for stirring and methods of stirring

Citations (4)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
FR2379339A1 (fr) *	1977-02-03	1978-09-01	Asea Ab	Dispositif de brassage pour coulee continue
FR2485411A1 (fr) *	1980-06-27	1981-12-31	Siderurgie Fse Inst Rech	Lingotiere de coulee continue electromagnetique de produits metalliques a section rectangulaire allongee
DE3510261A1 (de) *	1984-04-06	1985-10-17	Voest-Alpine Ag, Linz	Ruehreinrichtung an einer stranggiessanlage
EP0197482A2 (de) *	1985-04-10	1986-10-15	Paul Metz	Vorrichtung zum Rühren des flüssigen Metalls in einer Stranggiessanlage

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
SE410153B (sv) *	1976-05-21	1979-10-01	Asea Ab	Anleggning vid strenggjutning
DE2828160B2 (de) *	1978-06-23	1981-04-30	Aeg-Elotherm Gmbh, 5630 Remscheid	Elektromagnetische Rühreinrichtung für Stranggießanlagen

1987
- 1987-04-13 FR FR8705202A patent/FR2613647B1/fr not_active Expired - Fee Related
1988
- 1988-04-06 AT AT88105460T patent/ATE67436T1/de not_active IP Right Cessation
- 1988-04-06 DE DE8888105460T patent/DE3864880D1/de not_active Expired - Fee Related
- 1988-04-06 EP EP88105460A patent/EP0286960B1/de not_active Expired - Lifetime
- 1988-04-12 JP JP63090144A patent/JPS63268544A/ja active Granted
- 1988-04-12 CA CA000563914A patent/CA1326585C/fr not_active Expired - Fee Related
- 1988-04-12 US US07/180,754 patent/US4834168A/en not_active Expired - Fee Related

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
FR2379339A1 (fr) *	1977-02-03	1978-09-01	Asea Ab	Dispositif de brassage pour coulee continue
FR2485411A1 (fr) *	1980-06-27	1981-12-31	Siderurgie Fse Inst Rech	Lingotiere de coulee continue electromagnetique de produits metalliques a section rectangulaire allongee
DE3510261A1 (de) *	1984-04-06	1985-10-17	Voest-Alpine Ag, Linz	Ruehreinrichtung an einer stranggiessanlage
EP0197482A2 (de) *	1985-04-10	1986-10-15	Paul Metz	Vorrichtung zum Rühren des flüssigen Metalls in einer Stranggiessanlage

Also Published As

Publication number	Publication date
CA1326585C (fr)	1994-02-01
EP0286960B1 (de)	1991-09-18
FR2613647A1 (fr)	1988-10-14
ATE67436T1 (de)	1991-10-15
US4834168A (en)	1989-05-30
JPH0225698B2 (de)	1990-06-05
DE3864880D1 (de)	1991-10-24
JPS63268544A (ja)	1988-11-07
FR2613647B1 (fr)	1990-11-16

Publication	Publication Date	Title
EP0286960B1 (de)	1991-09-18	Vorrichtung zum elektromagnetischen Rühren von flüssigem Metall in einer Stranggusslinie
EP2550121B1 (de)	2016-03-09	Rührwalze für eine maschine zum durchgehenden giessen von platten
CA1091787A (fr)	1980-12-16	Procede et dispositif pour le brassage electromagnetique de produits metalliques coules en continu
EP1954427B1 (de)	2010-08-04	Einstellung des modus von elektromagnetischem rühren über die höhe einer stranggussform
CA2312876C (fr)	2008-10-14	Equipement de freinage electromagnetique d'un metal en fusion dans une installation de coulee continue
FR2477691A1 (fr)	1981-09-11	Poches de coulee ou fours a poche de coulee a courant continu
EP0351327B1 (de)	1992-02-12	Verfahren zur Herstellung von thixotropen metallischen Produkten mittels Strangguss
US20110319270A1 (en)	2011-12-29	Apparatus for Melting Metal Pieces
EP0005676A2 (de)	1979-11-28	Elektromagnetisches Rührverfahren beim Stranggiessen
CA1195823A (fr)	1985-10-29	Procede de fabrication de corps creux par coulee continue a l'aide d'un champ magnetique et dispositif de mise en oeuvre du procede
FR2483817A1 (fr)	1981-12-11	Agitateur magnetique
EP1259343B1 (de)	2003-09-03	Vorrichtung zur beschickung von flüssigem metall in eine stranggusskokille und verfahren zu deren verwendung
FR2485411A1 (fr)	1981-12-31	Lingotiere de coulee continue electromagnetique de produits metalliques a section rectangulaire allongee
FR2632549A1 (fr)	1989-12-15	Lingotiere pour la coulee continue de billettes ou de blooms
FR2516095A1 (fr)	1983-05-13	Installation d'affinage equipee d'un dispositif de mesure de la temperature et/ou de prelevement d'echantillons d'un bain d'acier liquide
EP0097561B2 (de)	1993-12-08	Verfahren und Vorrichtung zum elektromagnetischen Rühren stranggegossener Brammen, insbesondere aus Stahl
EP3405301B1 (de)	2021-05-05	Verfahren für rotierendes elektromagnetisches rühren einer metallschmelze beim giessen eines produkts mit grossem querschnitt und vorrichtung zur durchführung des verfahrens
FR2479046A1 (fr)	1981-10-02	Agitateur electromagnetique pour acier liquide
FR2601270A1 (fr)	1988-01-15	Dispositif electromagnetique, a champ tournant, de brassage du metal liquide en coulee continue.
WO2007065983A1 (fr)	2007-06-14	Dispositif de brassage electromagnetique de metal liquide pour ligne de coulee continue
FR2495752A1 (fr)	1982-06-11	Dispositif de chauffage electrique par induction de produits electroconducteurs solides
CH629127A5 (en)	1982-04-15	Continuous-casting method
BE563076A (de)
FR2525754A1 (fr)	1983-10-28	Four a canaux a induction
FR2476511A1 (fr)	1981-08-28	Procede pour augmenter la largeur d'une brame coulee en continu sans interrompre la coulee et lingotiere pour la mise en oeuvre de ce procede

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