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EP0062606A1 - Device for cooling a cast strand during continuous casting - Google Patents

Device for cooling a cast strand during continuous casting Download PDF

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Publication number
EP0062606A1
EP0062606A1 EP82810127A EP82810127A EP0062606A1 EP 0062606 A1 EP0062606 A1 EP 0062606A1 EP 82810127 A EP82810127 A EP 82810127A EP 82810127 A EP82810127 A EP 82810127A EP 0062606 A1 EP0062606 A1 EP 0062606A1
Authority
EP
European Patent Office
Prior art keywords
coolant
strand
recesses
casting
continuous casting
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.)
Granted
Application number
EP82810127A
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German (de)
French (fr)
Other versions
EP0062606B1 (en
Inventor
Walter Haller
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.)
Alcan Holdings Switzerland AG
Original Assignee
Alusuisse Holdings AG
Schweizerische Aluminium AG
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 Alusuisse Holdings AG, Schweizerische Aluminium AG filed Critical Alusuisse Holdings AG
Publication of EP0062606A1 publication Critical patent/EP0062606A1/en
Application granted granted Critical
Publication of EP0062606B1 publication Critical patent/EP0062606B1/en
Expired legal-status Critical Current

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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
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/124—Accessories for subsequent treating or working cast stock in situ for cooling
    • 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
    • B22D11/01—Continuous casting of metals, i.e. casting in indefinite lengths without moulds, e.g. on molten surfaces
    • B22D11/015—Continuous casting of metals, i.e. casting in indefinite lengths without moulds, e.g. on molten surfaces using magnetic field for conformation, i.e. the metal is not in contact with a mould
    • 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
    • B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
    • B22D11/049—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds for direct chill casting, e.g. electromagnetic casting

Definitions

  • the invention relates to a method for cooling a casting strand emerging from a continuous casting mold during continuous casting by applying coolant directly to the circumference of the strand.
  • heat is removed from the casting strand emerging from the mold by applying coolant to the surface of the strand directly below the mold.
  • the coolant initially only touches the start-up floor.
  • the indirect heat removal that occurs leads to a mild solidification of the liquid metal and to an even formation of the strand base.
  • the coolant strikes the surface of the strand, which is associated with a sudden increase in heat dissipation from the casting strand.
  • the thermal stresses that occur as a result of this temperature shock are greater than the tensile strength of the cast strand and lead to permanent deformation in the form of a convex curvature of the strand base and, if the tensile strength is exceeded, to cracks in the strand.
  • the strand In order to obtain a casting strand with a flat foot, the strand must not be cooled too much during the start-up process.
  • a method is known in which the coolant is applied in a pulsating manner to reduce the cooling intensity, at least during the starting process.
  • the inventor has set the goal of controlling the cooling in such a way that a casting strand with an essentially flat base is obtained.
  • easy handling should be ensured.
  • the coolant is applied as coolant jets at least during the start-up process in zones which are kept at a distance from one another.
  • the coolant jets are preferably applied in a width whose ratio to the distance of the adjacent coolant jet is between 1:10 and 1: 1.5, in particular especially between 1: 6 and 1: 2, and the distance between adjacent zones is 5 to 50 mm.
  • the method according to the invention can be implemented with any continuous casting mold, but is technically particularly simple with an electromagnetic continuous casting mold, which has a cooling device with a nozzle directed towards the surface of the casting strand with a nozzle opening designed as an annular gap for a liquid coolant.
  • the annular gap in the flow direction of the coolant is followed by a deflecting surface which is arranged parallel to the casting strand axis and can be displaced at least parallel to this and has at least one recess which projects into the path of the coolant emerging from the annular gap.
  • the deflecting surface is provided with tongues arranged tongues, separated by recesses.
  • the ratio between the width of the recesses and the distance between adjacent recesses is between 1:10 and 1: 1.5, in particular between 1: 6 and 1: 2, the distance between adjacent recesses being 5 to 50 mm.
  • the tongues can additionally have recesses lying parallel to the recesses, the length of which is smaller than the length of the recesses. This arrangement enables an increase in the cooling intention after the start-up process via an intermediate stage.
  • the deflection surface can be designed to be rotatable about the casting strand axis.
  • the method according to the invention can also be carried out with an electromagnetic continuous casting mold of the type mentioned above, in which, according to the invention, tubular nozzles for a gas are arranged parallel to the axis of the casting strand, the nozzle openings of which end above the path of the coolant emerging from the annular gap.
  • the coolant is deflected here by the gas stream emerging from the nozzles.
  • the distance between adjacent nozzles is preferably between 5 and 50 mm, in particular between 15 and 25 mm.
  • the nozzles can be connected to a ring line.
  • an induction coil 4 which is formed by a hollow profile in the exemplary embodiments shown, is placed around a casting opening for a casting strand 1 with a starting base 2 resting on a starting base 2.
  • This is mounted on a multi-part support body 5, 6 formed from insulating material, which has corresponding recesses on its inside for receiving the induction coil 4.
  • the upper support body 6 is connected to a metallic cover 7 and delimits cavities for a flowing coolant.
  • An electromagnetic shield 8 which is connected to the cover 7 by a screw thread, is used to adapt the magnetic field to the increasing metallostatic pressure in the casting strand 1, and a selected position of the shield 8 can be fixed by locking screws 9.
  • this screen 8 is preceded by a jacket 10 made of refractory, insulating material towards the pouring opening.
  • an insulating body 11 is attached, which together with the outer surface of the electromagnetic screen 8 forms an annular gap 12 through which coolant 13 is sprayed onto the casting strand 1.
  • the coolant is introduced into the cavity formed by the upper support body 6 and its cover 7, then flows through various fluid dynamic calming elements - for example a screen plate 14 with holes 15 - as well as a collar-like weir 16 and then exits through the annular gap 12 at a predetermined angle , which is given by the function of the screen 8 for adapting the magnetic field to the metallostatic pressure in the casting strand.
  • a baffle 17 - for example a 0.5 mm thick baffle made of stainless steel - protrudes parallel to the casting strand axis and acts as a baffle represents a deflecting element for the coolant and the inner contour of which is adapted to the cross-sectional contour of the casting strand-1.
  • racks 18 are fastened to this, which are each in engagement with the associated gear wheels 19 of a drive device (not shown in the drawing).
  • the baffle 17 shown in FIG. 2 has, at a distance b of, for example, 20 mm, recesses 21 of a length 1 of, for example, 25 mm and a width of, for example, 5 mm, which are separated from one another by tongues arranged in tongues 20.
  • X denotes a section line of the coolant 13 emerging from the annular gap 12 with the plane of the baffle plate 17.
  • each tongue 20 is additionally provided with a recess 22.
  • the length 1 1 of the recesses 21 is, for example, 25 mm and the length 1 2 of the recesses 22 is 15 mm.
  • the recesses 21 or recesses 22 have a width a or d of, for example, 5 mm.
  • the cutouts 22 lie in the middle between two cutouts 21, ie the distance c between one cutout and an adjacent cutout is 10 mm.
  • X 1 and X 2 denote two different cutting lines of the coolant 13 emerging from the annular gap 12 with the plane of the baffle 17. The cutting line X 1 only cuts the recesses, the cutting line X 2 also the recesses.
  • tubular nozzles 23 are arranged parallel to the axis of the casting strand, the nozzle opening of which is at a distance of 5 mm, for example, from the nozzle axis to the flow path of the coolant 13 emerging from the annular gap 12; the distance between the individual nozzles 23 is, for example, 20 mm.
  • the nozzles 23 are connected to a ring line 24 formed by a hollow profile, which is connected to a compressed air tank via a line (not shown in FIG. 4).
  • the ring line 24 is attached to angled brackets 25 which rest on the upper edge of the continuous casting mold.
  • the partial deflection of the coolant 13 emerging from the annular gap 12 causes an interruption of the line of incidence Y of the coolant on the surface of the casting strand 1, as shown in FIG. 5.
  • the cooling surfaces 26 impinging on the surface of the casting strand and flowing thereon have one Width a of for example 5 mm and are at a distance b of for example 25 mm.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Basic Packing Technique (AREA)

Abstract

Die Kühlung eines aus einer Stranggiesskokille während des Stranggiessens austretenden Giessstranges (1) erfolgt durch Aufbringen von Kühlmittel unmittelbar auf den Strangumfang. Zur Verminderung der bei zu schroffer Abkühlung des Stranges auftretenden Wölbung des Strangfusses (3) wird das Kühlmittel (13) zumindest während des Anfahrvorganges in zueinander in Abstand gehaltenen Zonen als Kühlmittelstrahlen aufgebracht. Das Verfahren lässt sich technisch besonders einfach mit einer elektromagnetischen Stranggiesskokille realisieren, welche eine Kühlvorrichtung mit einer auf die Oberfläche des Giessstranges (1) gerichteten Düse mit als Ringspalt (12) ausgebildeter Düsenöffnung für ein flüssiges Kühlmittel aufweist. Dem Ringspalt (12) ist in Strömungsrichtung des Kühlmittels ein parallel zur Giessstrangachse angeordnetes und parallel zu dieser verschiebbares Ablenkblech (17) mit zinnenartig angeordneten, durch Ausnehmungen getrennten Zungen nachgeschaltet, welches in die Bahn des aus dem Ringspalt austretenden Kühlmittels einragt.A casting strand (1) emerging from a continuous casting mold during the continuous casting is cooled by applying coolant directly to the circumference of the strand. In order to reduce the curvature of the strand foot (3) which occurs when the strand is cooled too abruptly, the coolant (13) is applied as coolant jets at least during the start-up process in zones spaced apart from one another. The method can be implemented in a technically particularly simple manner with an electromagnetic continuous casting mold, which has a cooling device with a nozzle directed towards the surface of the casting strand (1) with a nozzle opening designed as an annular gap (12) for a liquid coolant. Downstream of the annular gap (12) in the flow direction of the coolant is a baffle plate (17), which is arranged parallel to the casting strand axis and can be displaced parallel to it, and has tongues arranged and separated by recesses, which protrudes into the path of the coolant emerging from the annular gap.

Description

Die Erfindung betrifft ein Verfahren zum Kühlen eines aus einer Stranggiesskokille während des Stranggiessens austretenden Giessstranges durch Aufbringen von Kühlmittel unmittelbar auf den Strangumfang.The invention relates to a method for cooling a casting strand emerging from a continuous casting mold during continuous casting by applying coolant directly to the circumference of the strand.

Beim Stranggiessen mit direkter Kühlung wird dem aus der Kokille austretenden Giessstrang durch Beaufschlagen der Strangoberfläche mit Kühlmittel unmittelbar unterhalb der Kokille Wärme entzogen. Während des Anfahrvorganges berührt das Kühlmittel zunächst nur den Anfahrboden. Der hierbei eintretende indirekte Wärmeentzug führt zu einer milden Erstarrung des flüssigen Metalls und zu einer ebenen Ausbildung des Strangfusses. Mit fortschreitendem Absenken des Anfahrbodens trifft das Kühlmittel direkt auf die Oberfläche des Stranges auf, was mit einer sprunghaften Erhöhung der Wärmeabfuhr aus dem Giessstrang verbunden ist. Die als Folge dieses Temperaturschocks auftretenden Wärmespannungen sind grösser als die Dehnungsfestigkeit des Giessstranges und führen zu einer bleibenden Verformung in Form einer konvexen Wölbung des Strangfusses und bei Ueberschreiten der Zerreissfestigkeit überdies zu Rissen im Strang. Um einen Giessstrang mit ebenem Fuss zu erhalten, darf der Strang demzufolge während des Anfahrvorganges nicht zu stark gekühlt werden.In continuous casting with direct cooling, heat is removed from the casting strand emerging from the mold by applying coolant to the surface of the strand directly below the mold. During the start-up process, the coolant initially only touches the start-up floor. The indirect heat removal that occurs leads to a mild solidification of the liquid metal and to an even formation of the strand base. With the progressive lowering of the start-up floor, the coolant strikes the surface of the strand, which is associated with a sudden increase in heat dissipation from the casting strand. The thermal stresses that occur as a result of this temperature shock are greater than the tensile strength of the cast strand and lead to permanent deformation in the form of a convex curvature of the strand base and, if the tensile strength is exceeded, to cracks in the strand. In order to obtain a casting strand with a flat foot, the strand must not be cooled too much during the start-up process.

Es ist ein Verfahren bekannt, bei dem das Kühlmittel zur Verminderung der Kühlintensität zumindest während des Anfahrvorganges pulsierend aufgebracht wird.A method is known in which the coolant is applied in a pulsating manner to reduce the cooling intensity, at least during the starting process.

Weiterhin ist ein Verfahren bekannt geworden, bei dem ein Kühlmittel mit in diesem gelöstem Gas verwendet wird, welches beim Auftreffen des Kühlmittels auf der Strangoberfläche einen den Wärmeabfluss vermindernden Isolierfilm bildet.Furthermore, a method has become known in which a coolant with gas dissolved in it is used, which ei when the coolant hits the strand surface an insulating film that reduces heat flow.

Die den genannten Verfahren anhaftenden Nachteile sind einerseits die durch das pulsierend aufgebrachte Kühlmittel auftretenden Vibrationen, die sich negativ auf die Gefügeausbildung im Strang während des Erstarrungsvorganges auswirken können; andererseits macht die Anwendung eines Kühlmittels mit darin gelöstem Gas eine komplizierte Kontrolleinrichtung erforderlich.The disadvantages associated with the above-mentioned processes are, on the one hand, the vibrations caused by the pulsatingly applied coolant, which can have a negative effect on the microstructure formation in the strand during the solidification process; on the other hand, the use of a coolant with gas dissolved therein requires a complicated control device.

Angesichts dieser Gegebenheiten hat sich der Erfinder das Ziel gesetzt, die Kühlung so zu steuern, dass ein Giessstrang mit im wesentlichen ebenem Fuss erhalten wird. Zudem soll eine einfache Handhabung gewährleistet werden.In view of these circumstances, the inventor has set the goal of controlling the cooling in such a way that a casting strand with an essentially flat base is obtained. In addition, easy handling should be ensured.

Zur Lösung dieser Aufgabe führt, dass das Kühlmittel zumindest während des Anfahrvorganges in zueinander in Abstand gehaltenen Zonen als Kühlmittelstrahlen aufgebracht wird.To achieve this object, the coolant is applied as coolant jets at least during the start-up process in zones which are kept at a distance from one another.

Wird diese Auftreffgeometrie des Kühlmittels auf der Oberfläche des Giessstranges über mindestens die ersten 100 mm des Stranges aufrecht erhalten, so bildet sich als Folge der verminderten Kühlwirkung ein praktisch wölbungsfreier Fuss aus. Nachdem der aus der Kokille austretende Strang eine Länge von etwa 10 cm erreicht und sich der Fuss durchgehend verfestigt hat, kann die Kühlung in der üblichen Weise -- d.h. ohne Unterteilung des Kühlmittels in einzelne Kühlmittelstrahlen -- fortgesetzt werden, da die Gefahr einer Wölbung nicht mehr besteht. In gewissen Fällen kann es sich jedoch als zweckmässig erweisen, die erfingungsgemässe Auftreffgeometrie des Kühlmittels während des gesamten Giessvorganges beizubehalten.If this impact geometry of the coolant on the surface of the casting strand is maintained for at least the first 100 mm of the strand, a practically arch-free foot is formed as a result of the reduced cooling effect. After the strand emerging from the mold has reached a length of about 10 cm and the foot has solidified continuously, cooling can be carried out in the usual way - i.e. without dividing the coolant into individual coolant jets - as there is no longer any risk of bulging. In certain cases, however, it may prove expedient to maintain the impact geometry of the coolant according to the invention during the entire casting process.

Bevorzugtermassen werden die Kühlmittelstrahlen in einer Breite aufgebracht, deren Verhältnis zum Abstand des benachbarten Kühlmittelstrahl zwischen 1 : 10 und 1 : 1,5, insbesondere zwischen 1 : 6 und 1 : 2, liegt und der Abstand benachbarter Zonen 5 bis 50 mm beträgt.The coolant jets are preferably applied in a width whose ratio to the distance of the adjacent coolant jet is between 1:10 and 1: 1.5, in particular especially between 1: 6 and 1: 2, and the distance between adjacent zones is 5 to 50 mm.

Das erfindungsgemässe Verfahren lässt sich mit jeder Stranggiesskokille, jedoch technisch besonders einfach mit einer elektromagnetischen Stranggiesskokille realisieren, welche eine Kühlvorrichtung mit einer auf die Oberfläche des Giessstranges gerichteten Düse mit als Ringspalt ausgebildeter Düsenöffnung für ein flüssiges Kühlmittel aufweist. Erfindungsgemäss wird dem Ringspalt in Strömungsrichtung des Kühlmittels eine parallel zur Giessstrangachse angeordnete und zumindest parallel zu dieser verschiebbare Ablenkfläche mit wenigstens einer Ausnehmung nachgeschaltet, welche in die Bahn des aus dem Ringspalt austretenden Kühlmittels einragt.The method according to the invention can be implemented with any continuous casting mold, but is technically particularly simple with an electromagnetic continuous casting mold, which has a cooling device with a nozzle directed towards the surface of the casting strand with a nozzle opening designed as an annular gap for a liquid coolant. According to the invention, the annular gap in the flow direction of the coolant is followed by a deflecting surface which is arranged parallel to the casting strand axis and can be displaced at least parallel to this and has at least one recess which projects into the path of the coolant emerging from the annular gap.

Die Ablenkfläche ist nach einem bevorzugten Merkmal der Erfindung mit zinnenartig angeordneten, durch Ausnehmungen getrennten Zungen versehen.According to a preferred feature of the invention, the deflecting surface is provided with tongues arranged tongues, separated by recesses.

Nach einem weiteren Merkmal der Erfindung liegt das Verhältnis zwischen Breite der Ausnehmungen und Abstand benachbarter Ausnehmungen zwischen 1 : 10 und 1 : l,5,insbesondere zwischen 1 : 6 und 1 : 2, wobei der Abstand benachbarter Ausnehmungen 5 bis 50 mm beträgt.According to a further feature of the invention, the ratio between the width of the recesses and the distance between adjacent recesses is between 1:10 and 1: 1.5, in particular between 1: 6 and 1: 2, the distance between adjacent recesses being 5 to 50 mm.

Die Zungen können zusätzlich parallel zu den Ausnehmungen liegende Aussparungen aufweisen, deren Länge kleiner ist als die Länge der Ausnehmungen. Diese Anordnung ermöglicht eine Erhöhung der Kühlintentsität nach dem Anfahrvorgang über eine Zwischenstufe.The tongues can additionally have recesses lying parallel to the recesses, the length of which is smaller than the length of the recesses. This arrangement enables an increase in the cooling intention after the start-up process via an intermediate stage.

Beim Giessen von Strängen mit rundem Querschnitt kann die Ablenkfläche um die Giessstrangachse.drehbar ausgebildet sein.When casting strands with a round cross section, the deflection surface can be designed to be rotatable about the casting strand axis.

Das erfindungsgemässe Verfahren lässt sich auch mit einer elektromagnetischen Stranggiesskokille der oben erwähnten Art durchführen, bei der erfindungsgemäss parallel zur Giessstrangachse rohrartige Düsen für ein Gas angeordnet sind, deren Düsenöffnungen oberhalb der Bahn des aus dem Ringspalt austretenden Kühlmittels enden. Die Ablenkung des Kühlmittels erfolgt hier durch den aus den Düsen austretenden Gasstrom.The method according to the invention can also be carried out with an electromagnetic continuous casting mold of the type mentioned above, in which, according to the invention, tubular nozzles for a gas are arranged parallel to the axis of the casting strand, the nozzle openings of which end above the path of the coolant emerging from the annular gap. The coolant is deflected here by the gas stream emerging from the nozzles.

Der Abstand benachbarter Düsen liegt bevorzugtermassen zwischen 5 und 50 mm, insbesondere zwischen 15 und 25 mm. Die Düsen können an eine Ringleitung angeschlossen sein.The distance between adjacent nozzles is preferably between 5 and 50 mm, in particular between 15 and 25 mm. The nozzles can be connected to a ring line.

Weitere Vorteile, Merkmale und Einzelheiten der Erfindung ergeben sich aus der nachfolgenden Beschreibung bevorzugter Ausführungsbeispiele sowie anhand der Zeichnung; diese zeigt in

  • Fig. 1: einen Querschnitt durch einen Teil einer Stranggiesskokille mit einem Ablenkblech;
  • Fig. 2 und 3: zwei Ausführungsformen des Ablenkbleches;
  • Fig. 4: einen Querschnitt durch einen Teil einer Stranggiesskokille mit Ablenkdüsen;
  • Fig. 5: Kühlflächen auf einer Giessstrangoberfläche bei Durchführung des erfindungsgemässen Verfahrens.
Further advantages, features and details of the invention emerge from the following description of preferred exemplary embodiments and with reference to the drawing; this shows in
  • 1: a cross section through part of a continuous casting mold with a baffle;
  • 2 and 3: two embodiments of the baffle;
  • 4 shows a cross section through part of a continuous casting mold with deflection nozzles;
  • 5: cooling surfaces on a casting strand surface when carrying out the method according to the invention.

Bei einer elektromagnetischen Strangiesskokille ist um eine Giessöffnung für einen Giessstrang 1 mit einem Anfahrboden 2 anliegenden Strangfuss 3 eine -- in den dargestellten Ausführungsbeispielen von einem Hohlprofil gebildete -- Induktionsspule 4 gelegt. Diese ist an einem aus isolierendem Werkstoff geformten mehrteiligen Tragkörper 5,6 gelagert, der an seiner Innenseite entsprechende Ausnehmungen zur Aufnahme der Induktionsspule 4 aufweist. Der obere Tragkörper 6 ist mit einem metallischen Deckel 7 verbunden und begrenzt mit diesem Hohlräume für ein fliessendes Kühlmittel.In the case of an electromagnetic continuous casting mold, an induction coil 4, which is formed by a hollow profile in the exemplary embodiments shown, is placed around a casting opening for a casting strand 1 with a starting base 2 resting on a starting base 2. This is mounted on a multi-part support body 5, 6 formed from insulating material, which has corresponding recesses on its inside for receiving the induction coil 4. The upper support body 6 is connected to a metallic cover 7 and delimits cavities for a flowing coolant.

Zur Anpassung des Magnetfeldes an den zunehmenden metallostatischen Druck im Giessstrang 1 dient ein elektromagnetischer Schirm 8, der mit dem Deckel 7 durch ein Schraubgewinde verbunden ist, wobei eine einmal gewählte Lage des Schirmes 8 durch Feststellschrauben 9 fixiert werden kann. Diesem Schirm 8 ist in den Ausführungsformen nach den Figuren 1 und 4 zur Giessöffnung hin ein Mantel l0 aus feuerfestem, isolierendem Werkstoff vorgeschaltet.An electromagnetic shield 8, which is connected to the cover 7 by a screw thread, is used to adapt the magnetic field to the increasing metallostatic pressure in the casting strand 1, and a selected position of the shield 8 can be fixed by locking screws 9. In the embodiments according to FIGS. 1 and 4, this screen 8 is preceded by a jacket 10 made of refractory, insulating material towards the pouring opening.

An der Innenseite des oberen Tragkörpers 6 ist ein Isolierkörper 11 angebracht, der zusammen mit der Aussenfläche des elektromagnetischen Schirmes 8 einen Ringspalt 12 bildet, durch den Kühlmittel 13 auf den Giessstrang 1 gespritzt wird. Das Kühlmittel wird in den vom oberen Tragkörper 6 und seinem Deckel 7 gebildeten Hohlraum eingeleitet, durchströmt anschliessend verschiedene strömungsdynamische Beruhigungselemente -- beispielsweise wiedergegebene Siebplatte 14 mit Löchern 15 -- sowie ein kragenartiges Wehr 16 und tritt dann durch den Ringspalt 12 in einem vorbestimmten Winkel aus, der durch die Funktion des Schirmes 8 zur Anpassung des Magnetfeldes an den metallostatischen Druck im Giessstrang gegeben ist.On the inside of the upper support body 6, an insulating body 11 is attached, which together with the outer surface of the electromagnetic screen 8 forms an annular gap 12 through which coolant 13 is sprayed onto the casting strand 1. The coolant is introduced into the cavity formed by the upper support body 6 and its cover 7, then flows through various fluid dynamic calming elements - for example a screen plate 14 with holes 15 - as well as a collar-like weir 16 and then exits through the annular gap 12 at a predetermined angle , which is given by the function of the screen 8 for adapting the magnetic field to the metallostatic pressure in the casting strand.

In die Strömungsbahn des aus dem Ringspalt 12 austretenden Kühlmittels 13 ragt -- wie in Fig. 1 dargestellt -- parallel zur Giessstrangachse eine Ablenkfläche 17 -- beispielsweise ein 0,5 mm dickes, aus nichtrostendem Stahl gefertigtes Ablenkblech -- ein, die als Prallfläche für das Kühlmittel ein Umlenkorgan darstellt und deren Innenkontur der Querschnittskontur des Giessstranges-1 angepasst ist. Um ein Verschieben des Ablenkbleches 17 parallel zur Giessstrangachse während des Giessbetriebes zu ermöglichen, sind an diesem Zahnstangen 18 befestigt, die jeweils mit diesen zugeordneten Zahnrädern 19 einer -- in der Zeichnung nicht dargestellten -- Antriebsvorrichtung in Eingriff stehen.In the flow path of the coolant 13 emerging from the annular gap 12, as shown in FIG. 1, a baffle 17 - for example a 0.5 mm thick baffle made of stainless steel - protrudes parallel to the casting strand axis and acts as a baffle represents a deflecting element for the coolant and the inner contour of which is adapted to the cross-sectional contour of the casting strand-1. In order to enable the deflection plate 17 to be displaced parallel to the casting strand axis during the casting operation, racks 18 are fastened to this, which are each in engagement with the associated gear wheels 19 of a drive device (not shown in the drawing).

Das in Fig. 2 dargestellte Ablenkblech 17 weist in einem Abstand b von beispielsweise 20 mm Ausnehmungen 21 einer Länge 1 von beispielsweise 25 mm und einer Breite a von beispielsweise 5 mm auf, die durch zinnenartig angeordnete Zungen 20 voneinander getrennt sind. Mit X ist eine Schnittlinie des aus dem Ringspalt 12 austretendenden Kühlmittels 13 mit der Ebene des Ablenkbleches 17 bezeichnet.The baffle 17 shown in FIG. 2 has, at a distance b of, for example, 20 mm, recesses 21 of a length 1 of, for example, 25 mm and a width of, for example, 5 mm, which are separated from one another by tongues arranged in tongues 20. X denotes a section line of the coolant 13 emerging from the annular gap 12 with the plane of the baffle plate 17.

Bei einer anderen Ausführungsform des-Ablenkbleches 17 ist gemäss Fig. 3 jede Zunge 20 zusätzlich mit einer Aussparung 22 versehen. Die Länge 11 der Ausnehmungen 21 beträgt beispielsweise 25 mm und die Länge 12 der Aussparungen 22 15 mm. Die Ausnehmungen 21 bzw. Aussparungen 22 weisen eine Breite a bzw. d von beispielsweise 5 mm auf. Die Aussparungen 22 liegen in der Mitte zwischen zwei Ausnehmungen 21, d.h. der Abstand c zwischen einer Ausnehmung und einer benachbarten Aussparung beträgt 10 mm. X1 und X2 bezeichnen zwei verschiedene Schnittlinien des aus dem Ringspalt 12 austretenden Kühlmittels 13 mit der Ebene des Ablenkbleches 17. Die Schnittlinie X1 schneidet nur die Ausnehmungen, die Schnittlinie X2 auch die Aussparungen.In another embodiment, the -. Baffle 17 as shown in FIG 3, each tongue 20 is additionally provided with a recess 22. The length 1 1 of the recesses 21 is, for example, 25 mm and the length 1 2 of the recesses 22 is 15 mm. The recesses 21 or recesses 22 have a width a or d of, for example, 5 mm. The cutouts 22 lie in the middle between two cutouts 21, ie the distance c between one cutout and an adjacent cutout is 10 mm. X 1 and X 2 denote two different cutting lines of the coolant 13 emerging from the annular gap 12 with the plane of the baffle 17. The cutting line X 1 only cuts the recesses, the cutting line X 2 also the recesses.

Bei der in Fig. 4 dargestellten Ausführungsform sind parallel zur Giessstrangachse rohrartige Düsen 23 angeordnet, deren Düsenöffnung zur Strömungsbahn des aus dem Ringspalt 12 austretenden Kühlmittels 13 einen in der Düsenachse gemessenen Abstand von beispielsweise 5 mm aufweist; der Abstand zwischen den einzelnen Düsen 23 beträgt beispielsweise 20 mm. Die Düsen 23 sind an eine von einem Hohlprofil gebildeten Ringleitung 24 angeschlossen, die über eine -- in Fig. 4 nicht dargestellte -- Zuleitung mit einem Druckluftbehälter verbunden ist. Die Ringleitung 24 ist an abgewinkelten Halterungen 25 befestigt, welche auf dem oberen Rand der Stranggiesskokille aufliegen.In the embodiment shown in FIG. 4, tubular nozzles 23 are arranged parallel to the axis of the casting strand, the nozzle opening of which is at a distance of 5 mm, for example, from the nozzle axis to the flow path of the coolant 13 emerging from the annular gap 12; the distance between the individual nozzles 23 is, for example, 20 mm. The nozzles 23 are connected to a ring line 24 formed by a hollow profile, which is connected to a compressed air tank via a line (not shown in FIG. 4). The ring line 24 is attached to angled brackets 25 which rest on the upper edge of the continuous casting mold.

Die teilweise Ablenkung des aus dem Ringspalt 12 austretenden Kühlmittels 13 bewirkt gemäss Fig. 5 eine Unterbrechung der Auftrefflinie Y des Kühlmittels auf der Oberfläche des Giessstranges 1. Die sich durch das auf der Oberfläche des Giessstranges auftreffende und an dieser heralfliessende Kühlmittel ergebenden Kühlflächen 26 haben eine Breite a von beispielsweise 5 mm und liegen in einem Abstand b von beispielsweise 25 mm.The partial deflection of the coolant 13 emerging from the annular gap 12 causes an interruption of the line of incidence Y of the coolant on the surface of the casting strand 1, as shown in FIG. 5. The cooling surfaces 26 impinging on the surface of the casting strand and flowing thereon have one Width a of for example 5 mm and are at a distance b of for example 25 mm.

Claims (10)

1. Verfahren zum Kühlen eines aus einer Stranggiesskokille während des Stranggiessens austretenden Giessstranges durch Aufbringen von Kühlmittel unmittelbar auf den Strangumfang,
dadurch gekennzeichnet,
dass das Kühlmittel zumindest während des Anfahrvorganges in zueinander in Abstand gehaltenen Zonen als Kühlmittelstrahlen aufgebracht wird.1. Method for cooling a casting strand emerging from a continuous casting mold during the continuous casting by applying coolant directly to the circumference of the strand,
characterized,
that the coolant is applied as coolant jets at least during the start-up process in zones spaced apart from one another. 2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass während des Aufbringens des Kühlmittels in zueinander in Abstand gehaltenen Zonen zumindest ein Strangende von etwa 100 mm Länge erzeugt wird.2. The method according to claim 1, characterized in that at least one strand end of about 100 mm in length is generated during the application of the coolant in zones spaced apart. 3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass das Kühlmittel während des gesamten Giessvorganges in zueinander in Abstand gehaltenen Zonen aufgebracht wird.3. The method according to claim 1, characterized in that the coolant is applied during the entire casting process in spaced zones. 4. Kühlvorrichtung an einer elektromagnetischen Stranggiesskokille zur Durchführung des Verfahrens nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass einer als Ringspalt (12) ausgebildeten Düsenöffnung für ein flüssiges Kühlmittel in Strömungsrichtung des Kühlmittels eine parallel zur Giessstrangachse angeordnete und zumindestens parallel zu dieser bewegbare Ablenkfläche (17) mit Ausnehmungen (21) nachgeschaltet ist.4. Cooling device on an electromagnetic continuous casting mold for performing the method according to one of claims 1 to 3, characterized in that a nozzle opening designed as an annular gap (12) for a liquid coolant in the flow direction of the coolant is arranged parallel to the casting strand axis and at least parallel to it movable Deflection surface (17) with recesses (21) is connected downstream. 5. Kühlvorrichtung nach Anspruch 4, dadurch gekennzeichnet, dass die Ablenkfläche (17) mit zinnenartig angeordneten, durch Ausnehmungen (21) getrennten Zungen (20) versehen ist.5. Cooling device according to claim 4, characterized in that the deflecting surface (17) is provided with crenellated tongues (20) separated by recesses (21). 6. Kühlvorrichtung nach Anspruch 5, dadurch gekennzeichnet, dass das Verhältnis zwischen Breite (a) der Ausnehmungen (21) und Abstand (b) benachbarter Ausnehmungen zwischen 1 : 10 und 1 : 1,5, vorzugsweise zwischen 1 : 6 und 1 : 2 liegt und der Abstand benachbarter Ausnehmungen (21) 5 bis 50 mm beträgt.6. Cooling device according to claim 5, characterized in that the ratio between the width (a) of the recesses (21) and the distance (b) of adjacent recesses between 1:10 and 1: 1.5, preferably between 1: 6 and 1: 2 lies and the distance between adjacent recesses (21) is 5 to 50 mm. 7. Kühlvorrichtung nach Anspruch 5, dadurch gekennzeichnet, dass die Zungen (20) parallel zu den Ausnehmungen (21) liegende Aussparungen (22) aufweisen, deren Länge (12) kleiner ist als die Länge (11) der Ausnehmungen.7. Cooling device according to claim 5, characterized in that the tongues (20) parallel to the recesses (21) have recesses (22) whose length (1 2 ) is less than the length (1 1 ) of the recesses. 8. Kühlvorrichtung nach einem der Ansprüche 4 bis 7 für einen Giessstrang runden Querscnnitts, dadurch gekennzeichnet, dass die Ablenkfläche (17) um die Giessstrangachse drehbar ausgebildet ist.8. Cooling device according to one of claims 4 to 7 for a casting strand round cross-section, characterized in that the deflecting surface (17) is rotatable about the casting strand axis. 9. Kühlvorrichtung an einer elektromagnetischen Stranggiesskokille zur Durchführung des Verfahrens nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass parallel zur Giessstrangachse rohrartige Düsen (23) für ein Gas angeordnet sind, deren Düsenöffnungen oberhalb der Bahn des aus dem Ringspalt (12) austretenden Kühlmittelstrahls enden.9. Cooling device on an electromagnetic continuous casting mold for carrying out the method according to one of claims 1 to 3, characterized in that tubular nozzles (23) for a gas are arranged parallel to the casting strand axis, the nozzle openings of which exit above the path of the annular gap (12) Coolant jet ends. 10. Kühlvorrichtung nach Anspruch 9, dadurch gekennzeichnet, dass benachbarte Düsen (23) einen Abstand zwischen 5 und 50 mm, vorzugsweise zwischen 15 und 25 mm, aufweisen.10. Cooling device according to claim 9, characterized in that adjacent nozzles (23) have a distance between 5 and 50 mm, preferably between 15 and 25 mm.
EP82810127A 1981-04-02 1982-03-19 Device for cooling a cast strand during continuous casting Expired EP0062606B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH2245/81 1981-04-02
CH224581 1981-04-02

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EP0062606A1 true EP0062606A1 (en) 1982-10-13
EP0062606B1 EP0062606B1 (en) 1985-02-06

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US (1) US4572280A (en)
EP (1) EP0062606B1 (en)
JP (1) JPS57177854A (en)
CA (1) CA1207511A (en)
DE (1) DE3262189D1 (en)
NO (1) NO157770C (en)
ZA (1) ZA821828B (en)

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EP0119981A1 (en) * 1983-02-15 1984-09-26 VOEST-ALPINE Aktiengesellschaft Jet nozzle
EP0337769A2 (en) * 1988-04-15 1989-10-18 Norsk Hydro A/S Continuous or semi-continuous casting apparatus for casting metallic materials
EP0533133A1 (en) * 1991-09-19 1993-03-24 Ykk Corporation Cooling method of continuous casting and its mold
EP0592360A1 (en) * 1992-10-06 1994-04-13 Alusuisse-Lonza Services Ag Machine for vertical continuous casting in a magnetic field
WO1994025202A1 (en) * 1993-05-03 1994-11-10 Norsk Hydro A.S Casting equipment for casting metal

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JPS63242443A (en) * 1987-03-31 1988-10-07 Sumitomo Light Metal Ind Ltd Casting apparatus in electromagnetic field
US6264767B1 (en) 1995-06-07 2001-07-24 Ipsco Enterprises Inc. Method of producing martensite-or bainite-rich steel using steckel mill and controlled cooling
WO2000003042A1 (en) 1998-07-10 2000-01-20 Ipsco Inc. Method and apparatus for producing martensite- or bainite-rich steel using steckel mill and controlled cooling
US6491087B1 (en) 2000-05-15 2002-12-10 Ravindra V. Tilak Direct chill casting mold system
US20050003387A1 (en) * 2003-02-21 2005-01-06 Irm Llc Methods and compositions for modulating apoptosis
US20050000679A1 (en) * 2003-07-01 2005-01-06 Brock James A. Horizontal direct chill casting apparatus and method
US7007739B2 (en) 2004-02-28 2006-03-07 Wagstaff, Inc. Direct chilled metal casting system
US20050189880A1 (en) * 2004-03-01 2005-09-01 Mitsubishi Chemical America. Inc. Gas-slip prepared reduced surface defect optical photoconductor aluminum alloy tube

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Cited By (8)

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Publication number Priority date Publication date Assignee Title
EP0119981A1 (en) * 1983-02-15 1984-09-26 VOEST-ALPINE Aktiengesellschaft Jet nozzle
EP0337769A2 (en) * 1988-04-15 1989-10-18 Norsk Hydro A/S Continuous or semi-continuous casting apparatus for casting metallic materials
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EP0533133A1 (en) * 1991-09-19 1993-03-24 Ykk Corporation Cooling method of continuous casting and its mold
EP0592360A1 (en) * 1992-10-06 1994-04-13 Alusuisse-Lonza Services Ag Machine for vertical continuous casting in a magnetic field
CH688129A5 (en) * 1992-10-06 1997-05-30 Alusuisse Lonza Services Ag Casting machine for the vertical continuous casting in a magnetic field.
WO1994025202A1 (en) * 1993-05-03 1994-11-10 Norsk Hydro A.S Casting equipment for casting metal

Also Published As

Publication number Publication date
NO157770C (en) 1988-05-18
ZA821828B (en) 1983-02-23
US4572280A (en) 1986-02-25
DE3262189D1 (en) 1985-03-21
CA1207511A (en) 1986-07-15
NO821082L (en) 1982-10-04
EP0062606B1 (en) 1985-02-06
NO157770B (en) 1988-02-08
JPH0436772B2 (en) 1992-06-17
JPS57177854A (en) 1982-11-01

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