EP0043987B1 - Apparatus for the continuous casting of metal in a closed gating system - Google Patents

Apparatus for the continuous casting of metal in a closed gating system Download PDF

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Publication number
EP0043987B1
EP0043987B1 EP81105098A EP81105098A EP0043987B1 EP 0043987 B1 EP0043987 B1 EP 0043987B1 EP 81105098 A EP81105098 A EP 81105098A EP 81105098 A EP81105098 A EP 81105098A EP 0043987 B1 EP0043987 B1 EP 0043987B1
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EP
European Patent Office
Prior art keywords
mold
mould
equipment according
pouring
metal
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Expired
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EP81105098A
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German (de)
French (fr)
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EP0043987A1 (en
Inventor
Wilfried Dr. Heinemann
Theodor Prof. Rummel
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SMS Concast AG
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Concast Holding AG
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Priority to AT81105098T priority Critical patent/ATE6476T1/en
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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
    • B22D1/00—Treatment of fused masses in the ladle or the supply runners before casting
    • 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
    • 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
    • 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
    • B22D11/045—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds for horizontal casting
    • B22D11/047—Means for joining tundish to mould
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D39/00—Equipment for supplying molten metal in rations
    • B22D39/003—Equipment for supplying molten metal in rations using electromagnetic field

Definitions

  • the invention relates to a device for continuous casting of metal with a closed pouring system, wherein a refractory distribution vessel pouring spout is connected to a cooled continuous mold, which has an approximately horizontal longitudinal axis.
  • the metal When continuously casting metal with a continuous mold, the metal can be fed in an open or in a closed pouring system.
  • Vertical and curved continuous casting plants are usually operated with an open pouring system, ie there is no connection between the distributor vessel and the continuous mold.
  • Horizontal continuous casters are almost exclusively built with a closed casting system, whereby refractory parts of the Veiteilervessel are connected to the pouring side of the continuous mold.
  • the closed pouring system offers the following advantages over the open pouring system. Contact of the Giesmetalles with atmospheric oxygen between the distri l ergefäss and the open-ended mold is etc. There is no bath level regulation in the mold.
  • a horizontal continuous casting installation is known from D E-OS No. 1558224, in which a distributor vessel is connected to a water-cooled mold.
  • the metal flows from the tundish into the mold without air admission, the flow speed being regulated by the pull-out speed of the strand.
  • the liquid Metai! begins to solidify not only in the mold, but already in the area of the connection level between the mold and the distributor vessel outlet opening, which leads to metal welds on the wall of the distributor vessel spout and as a result of the tensile force exerted on the strand by the pull-off rollers on the be; 3 its solidified strand circumference leads. This causes a considerable disturbance in the casting process and considerable material defects in the finished product.
  • a horizontal continuous casting method in which the metal is passed from a verte vessel through a refractory, nozzle-like expanding connecting line into the mold.
  • the liquid metal is subjected to electromagnetic forces in this nozzle-like connecting line, which cause acceleration in the direction of flow on the circumference of the metal strand.
  • the metal flow preformed and accelerated in the nozzle-like enlargement is intended to produce a free annular space in the suddenly expanded mold cross-section, whereby a stable meniscus is to be favored.
  • the device for generating the electromagnetic forces along the nozzle-like connecting line corresponds to a stator of a linear motor.
  • a neutral gas under pressure which is at least equal to the maximum ferrostatic pressure in this area, is introduced into the free annular space via a plurality of slots.
  • these complex process steps such as the application of an axial acceleration of the melt in the connecting line and the pressurization in the annular space, malfunctions in the annular space cannot be completely avoided when the line is at a standstill or when the strand extraction movement changes.
  • the injected inert gas can be entrained by the moving strand because of the lower ferrostatic pressure on the top side of the strand compared to the bottom side of the strand. On the one hand, this can produce additional disturbances in the annulus and, on the other hand, strand faults, particularly on the strand surface.
  • the welds already mentioned can occur on the end face of the nozzle-like connecting line with the disadvantages mentioned.
  • a method and a device for horizontal casting is further known from DE-OS No. 2756112.
  • liquid metal is drawn off from a lateral pouring opening of a container.
  • the gravity of the pouring casting metal is compensated for in a partial area after the pouring opening by an immaterial electromagnetic strand support and the ferrostatic pressure is kept under control by an additional electromagnetic coil.
  • These electromagnetic coil combined with the electromagnetic gravity compensation can be used on the one hand on a system for mold-free casting or on the other hand on a system with a horizontally oscillating mold and a fixed pouring opening.
  • the invention has for its object to solve the known difficulties at the connection point between a refractory distribution vessel pouring spout and a mold, such as welds, strand defects, openings, etc. with simple means.
  • the performance of such continuous casting plants is to be increased by extending the possible casting time.
  • the device according to the invention is characterized by the features according to claim 1.
  • the invention enables the advantages of the closed casting system for continuous casting with a horizontally arranged mold to be exploited using an inexpensive device.
  • the disadvantages known from the prior art, such as welds, string faults and breakthroughs can be eliminated. Longer sequences of pouring ladles can be poured due to significantly reduced wear in the pouring spout, which significantly reduces dead times and maintenance costs.
  • An additional reduction in wear on the refractory distributor spout can be achieved if, according to a further feature of the invention, the electromagnetic coil is arranged on both sides of the connection plane.
  • the invention further proposes to choose the outlet opening of the tundish spout and the mold inlet opening in the area of the connection level as well as the metal melt from the outlet opening by means of the electromagnetic Keep the field away.
  • outlet opening of the distribution vessel pouring spout is smaller than the mold inlet opening in the region of the connection plane.
  • the quality of the strand surface can be improved according to an additional feature if a mold part with a reduced thermal conductivity compared to the flow mold is arranged between the refractory distribution vessel pouring spout and the flow mold.
  • An additional improvement in the constricting effect of the electromagnetic field in the mold cavity can be achieved if the mold part consists of paramagnetic material with a correspondingly low thermal conductivity.
  • a refractory distribution vessel pouring spout 2 is connected to a cooled continuous mold 3 with a horizontal longitudinal axis 14 of the mold, which represents a closed pouring system.
  • a connection level 4 is located between the flow mold 3 and the distributor vessel pouring spout 2.
  • An electromagnetic coil 16, which causes a constriction 7 of the steel flowing into the flow mold 3, is arranged on both sides of the connection level 4.
  • a free annular space 8 is formed, so that the incoming steel cannot yet touch the mold 3 in the area of the connection plane 4.
  • the distribution vessel pouring spout 2 is part of a distribution vessel, not shown.
  • the continuous mold 3 is followed, as a rule, by known support guide elements (not shown) and a strand extraction unit for continuous or intermittent strand extraction.
  • a distance 15 between a water-cooled, electromagnetic, single-wind coil 16 and the mold cavity 19 below the horizontal longitudinal axis 14 of the continuous mold 3 is smaller than a distance 18 above the longitudinal axis 14.
  • This lining is advantageously made of paramagnetic material, such as stainless steel. So that no vacuum forms in the free annular space 8 (FIG. 1), which would counteract the constriction 7, an inert gas is fed from a container 22 via a pressure reducing valve 23 through fine feed slots 24 into the annular space 8. This pressure is adjusted to the atmospheric pressure and is so with less than the ferrostatic pressure of the melt.
  • the vacuum in the annular space 8 can also be used to introduce a lubricant for the strand.
  • a weakly oval-shaped electromagnetic coil 31 is arranged around a round strand cross section 32.
  • the method and the device according to the invention can basically be used for a large number of metals.
  • iron / carbon alloys can also be cast. Due to the free design possibility of the coil, only a few restrictions with regard to different strand formats are effective when using the invention.

Abstract

A method of casting metallic strands in a closed pouring or teeming system wherein the metal is cast through a refractory distributor vessel-pouring structure, such as a pouring spout, into an open-ended mold connected in flow communication with the pouring structure. To improve the quality of the strand and to increase the production capacity or output of such installations at the region of a connection plane of the distributor vessel-pouring structure and the open-ended mold the metallic melt is maintained away from the wall of the mold inlet opening by means of a constricting or bundling electromagnetic field.

Description

Die Erfindung betrifft eine Vorrichtung zum Stranggiessen von Metall mit einem geschlossenen Eingiesssystem, wobei ein feuerfester Verteilergefäss-Ausgussstutzen mit einer gekühlten Durchlaufkokille verbunden ist, die eine etwa horizontale Längsachse aufweist.The invention relates to a device for continuous casting of metal with a closed pouring system, wherein a refractory distribution vessel pouring spout is connected to a cooled continuous mold, which has an approximately horizontal longitudinal axis.

Beim Stranggiessen von Metall miteiner Durchlaufkokille kann die Metallzuführung in einem offenen oder in einem geschlossenen Eingiesssystem erfolgen. Vertikal- und Bogenstranggiessanlagen werden in der Regel mit offenem Eingiesssystem betrieben, d.h. zwischen Verteilergefäss und Durchlaufkokille besteht keine Verbindung. Horizontalstranggiessanlagen werden fast ausschliesslich mit geschlossenem E:ngiesssystem gebaut, wobei Feuerfestteile des Veiteilergefässes mit der Eingiessseite der Durchlaufkokille verbunden sind. Das geschlossene Eingiesssystem erbringt gegenüber dem offenen Eingiesssystem folgende Vorteile. Ein Kontakt des Giesmetalles mit Luftsauerstoff zwischen dem Verteilergefäss und der Durchlaufkokille ist ausgescniossen. Eine Badspiegelregulierung in der Kokille entfällt.When continuously casting metal with a continuous mold, the metal can be fed in an open or in a closed pouring system. Vertical and curved continuous casting plants are usually operated with an open pouring system, ie there is no connection between the distributor vessel and the continuous mold. Horizontal continuous casters are almost exclusively built with a closed casting system, whereby refractory parts of the Veiteilervessel are connected to the pouring side of the continuous mold. The closed pouring system offers the following advantages over the open pouring system. Contact of the Giesmetalles with atmospheric oxygen between the distri l ergefäss and the open-ended mold is ausgescniossen. There is no bath level regulation in the mold.

Es ist aus der D E-OS Nr. 1558224 eine horizontale Stranggiessanlage bekannt, be' welcher ein Verteilergefäss mit einer wassergekühlten Kokille verbunden ist. Das Metall fliesst dabei ohne Luftzutritt aus dem Verteilergefäss in die Kokille, wobei die Fliessgeschwindigkeit durch die Ausziehgeschwindigkeit des Stranges gereget ist. Es wurde festgestellt, dass das flüssige Metai! nicht erst in der Kokilie, sondern schon im Bereich der Verbindungsebene zwischen der Kokille und der Verteilergefäss-Austrittsöffnung zu erstarren beginnt, was zu Metallanschweissungen an der Wandung des Verteilergefäss-Ausgussstutzers und infolge des von den Abzugwalzen auf den Strang ausgeübten Zuges zu Rissen am be;3its erstarrten Strangumfang führt. Dies verursacht eine beträchtliche Störung des Giessvorganges und erhebliche Materialfehler am fertigen Erzeugnis. Durch Rissbildung in der noch dünren Strangkruste an der Kokillenausgangsseite sind deshalb Durchbrüche nicht auszuschliessen. die zu einer vollständigen Entleerung des vorgeschalteten Verteilergefässes führen. Das Anscnweissen des Metalles innerhalb der Verteilerge äss-Austrittsöffnung führt auch zu einer rasch en Zerstörung dieser Verbindungsleitung, wodurch die Dauer des Giessvorganges verkürzt wirc. Aus diesen Gründen hat insbesondere das kontinuierliche Stahlstranggiessverfahren mit horizontaler Kokille trotz beträchtlicher Verbesserungen sowohl bezüglich des Materials als auch cer Gestaltung solcher Verbindungsstücke noch einen breiten Eingang in die industrielle Technik gefunden.A horizontal continuous casting installation is known from D E-OS No. 1558224, in which a distributor vessel is connected to a water-cooled mold. The metal flows from the tundish into the mold without air admission, the flow speed being regulated by the pull-out speed of the strand. It was found that the liquid Metai! begins to solidify not only in the mold, but already in the area of the connection level between the mold and the distributor vessel outlet opening, which leads to metal welds on the wall of the distributor vessel spout and as a result of the tensile force exerted on the strand by the pull-off rollers on the be; 3 its solidified strand circumference leads. This causes a considerable disturbance in the casting process and considerable material defects in the finished product. Due to the formation of cracks in the still thin strand crust on the mold exit side, breakthroughs cannot be ruled out. which lead to a complete emptying of the upstream distribution vessel. The welding of the metal inside the distributor outlet opening also leads to a rapid destruction of this connecting line, which shortens the duration of the casting process. For these reasons, in particular the continuous steel continuous casting process with a horizontal mold, despite considerable improvements both in terms of the material and in the design of such connecting pieces, has found widespread use in industrial technology.

Aus der DE-OS Nr. 2455816 ist weiter ein horizontales Stranggiessverfahren bek-nnt, bei welchem das Metall aus einem Verte ergefäss über eine feuerfeste, düsenartig sich stark erweiternde Verbindungsleitung in die Kokille geleitet wird. Das flüssige Metall wird in dieser düsenartigen Verbindungsleitung elektromagnetischen Kräften unterworfen, die am Umfang des Metallstranges eine Beschleunigung in Strömungsrichtung hervorrufen. Der in der düsenartigen Erweiterung vorgeformte und beschleunigte Metallstrom soll im sprunghaft erweiterten Kokillenquerschnitt einen freien Ringraum erzeugen, wobei ein stabiler Meniskus begünstigt werden soll. Die Vorrichtung zur Erzeugung der elektromagnetischen Kräfte entlang der düsenartigen Verbindungsleitung entspricht einem Stator eines Linearmotors. Im freien Ringraum wird über eine Mehrzahl von Schlitzen ein neutrales Gas unter Druck eingeleitet, der mindestens gleich dem maximalen ferrostatischen Druck in diesem Bereich ist. Trotz diesen aufwendigen Verfahrensschritten wie das Aufbringen einer axialen Beschleunigung der Schmelze in der Verbindungsleitung und der Druckbeaufschlagung im Ringraum können bei Stillstand oder bei sich ändernder Strangausziehbewegung Störungen im Ringraum nicht ganz vermieden werden. Im weiteren kann das eingepresste inerte Gas wegen des geringeren ferrostatischen Druckes an der Strangoberseite verglichen zur Strangunterseite vom bewegten Strang mitgerissen werden. Dies kann einerseits zusätzliche Störungen im Ringraum und anderseits Strangfehler, insbesondere an der Strangoberfläche, erzeugen. Im weiteren können die bereits genannten Anschweissungen an der Stirnseite der düsenartigen Verbindungsleitung mit den erwähnten Nachteilen entstehen.From DE-OS No. 2455816 a horizontal continuous casting method is also known, in which the metal is passed from a verte vessel through a refractory, nozzle-like expanding connecting line into the mold. The liquid metal is subjected to electromagnetic forces in this nozzle-like connecting line, which cause acceleration in the direction of flow on the circumference of the metal strand. The metal flow preformed and accelerated in the nozzle-like enlargement is intended to produce a free annular space in the suddenly expanded mold cross-section, whereby a stable meniscus is to be favored. The device for generating the electromagnetic forces along the nozzle-like connecting line corresponds to a stator of a linear motor. A neutral gas under pressure, which is at least equal to the maximum ferrostatic pressure in this area, is introduced into the free annular space via a plurality of slots. Despite these complex process steps, such as the application of an axial acceleration of the melt in the connecting line and the pressurization in the annular space, malfunctions in the annular space cannot be completely avoided when the line is at a standstill or when the strand extraction movement changes. Furthermore, the injected inert gas can be entrained by the moving strand because of the lower ferrostatic pressure on the top side of the strand compared to the bottom side of the strand. On the one hand, this can produce additional disturbances in the annulus and, on the other hand, strand faults, particularly on the strand surface. Furthermore, the welds already mentioned can occur on the end face of the nozzle-like connecting line with the disadvantages mentioned.

Zum gleichzeitigen Giessen mehrerer Stränge ist es ferner aus der DE-OS Nr. 1608350 bekannt, vertikal angeordnete Stranggiesskokillen gasdicht mit einem gemeinsamen Verteilergefäss zu verbinden und Metall über Bodenausgussdüsen den Kokillen zuzuführen. Dabei kann zwischen dem feuerfesten Verteilergefäss-Ausgussstutzen und den gekühlten Kokillen wahlweise mit oder ohne Gaspolster gearbeitet werden. Bei diesen vertikal angeordneten Kokillen treten ebenfalls die aus dem horizontalen Stranggiessen bekannten Störungen zwischen dem feuerfesten Verteilergefäss-Ausgussstutzen und der gekühlten Durchlaufkokille auf. Auch trotz Verwendung einer verlängerten Ausgussdüse und einem Gaspolster zwischen der Kokille und dieser Düse bauen sich bei sich ändernden Giessbedingungen Anschweissungen an der Düse auf, die zu Störungen führen. Dieses Verfahren hat sich deshalb im industriellen Gebrauch nicht durchgesetzt.For simultaneous casting of several strands, it is also known from DE-OS No. 1608350 to connect vertically arranged continuous casting molds in a gastight manner to a common distributor vessel and to supply metal to the molds via bottom pouring nozzles. You can choose to work with or without a gas cushion between the refractory pouring spout and the chilled molds. With these vertically arranged molds, the disturbances known from horizontal continuous casting also occur between the refractory distribution vessel pouring spout and the cooled continuous mold. Despite the use of an extended pouring nozzle and a gas cushion between the mold and this nozzle, welds build up on the nozzle with changing casting conditions, which lead to faults. This process has therefore not become established in industrial use.

Ein Verfahren und eine Vorrichtung zum horizontalen Strantgiessen ist im weiteren aus der DE-OS Nr. 2756112 bekannt. Bei diesem Verfahren wird aus einer seitlichen Ausgussöffnung eines Behälters flüssiges Metall abgezogen. Dabei wird die Schwerkraft des ausfliessenden Giessmetalles in einem Teilbereich nach der Ausgussöffnung durch eine immaterielle elektromagnetische Strangunterstützung kompensiert und der ferrostatische Druck durch eine zusätzliche elektromagnetische Spule unter Kontrolle gehalten. Diese mit der elektromagnetischen Schwerkraftkompensation kombinierte elektromagnetische Spule kann einerseits auf einer Anlage zum kokillenlosen Giessen oder anderseits auf einer Anlage mit einer horizontal oszillierenden Kokille und einer feststehenden Ausgussöffnung verwendet werden.A method and a device for horizontal casting is further known from DE-OS No. 2756112. In this method, liquid metal is drawn off from a lateral pouring opening of a container. The gravity of the pouring casting metal is compensated for in a partial area after the pouring opening by an immaterial electromagnetic strand support and the ferrostatic pressure is kept under control by an additional electromagnetic coil. These electromagnetic coil combined with the electromagnetic gravity compensation can be used on the one hand on a system for mold-free casting or on the other hand on a system with a horizontally oscillating mold and a fixed pouring opening.

Der Erfindung liegt die Aufgabe zugrunde, die bekannten Schwierigkeiten an der Verbindungsstelle zwischen einem feuerfesten Verteilergefäss-Ausgussstutzen und einer Kokille, wie Anschweissungen, Strangfehler, Durchbrüche usw. mit einfachen Mitteln zu lösen. Zusätzlich soll auch die Leistung solcher Stranggiessanlagen durch Verlängerung der möglichen Giesszeit erhöht werden.The invention has for its object to solve the known difficulties at the connection point between a refractory distribution vessel pouring spout and a mold, such as welds, strand defects, openings, etc. with simple means. In addition, the performance of such continuous casting plants is to be increased by extending the possible casting time.

Die erfindungsgemässe Vorrichtung zeichnet sich durch die Merkmale gemäss Anspruch 1 aus. Die Erfindung ermöglicht unter Anwendung einer preisgünstigen Vorrichtung die Ausnützung der Vorteile des geschlossenen Giesssystems beim Stranggiessen mit horizontal angeordneter Kokille. Die aus dem Stand der Technik bekannten Nachteile, wie Anschweissungen, Strangfehler und Durchbrüche, können beseitigt werden. Durch einen wesentlich verminderten Verschleiss im Verteilergefäss-Ausgussstutzen können längere Sequenzen von Giesspfannen vergossen werden, wodurch sich Totzeiten und Unterhaltskosten wesentlich verringern.The device according to the invention is characterized by the features according to claim 1. The invention enables the advantages of the closed casting system for continuous casting with a horizontally arranged mold to be exploited using an inexpensive device. The disadvantages known from the prior art, such as welds, string faults and breakthroughs can be eliminated. Longer sequences of pouring ladles can be poured due to significantly reduced wear in the pouring spout, which significantly reduces dead times and maintenance costs.

Ein weiteres, noch nicht befriedigend gelöstes Problem beim bekannten geschlossenen Giesssystem stellt die Zuführung eines Schmiermittels in die Kokille dar. Mit der Erfindung wird eine gleichmässige Schmiermittelzufuhr dadurch ermöglicht, dass unter Ausnützung des Vakuums im Ringraum ein Schmiermittel für den Strang in diesen Ringraum eingebracht wird. Anstelle eines flüssigen, pasten- oder pulverförmigen Schmiermittels kann beispielsweise auch ein nicht oxydierendes Gas mit oder ohne Zusatzstoffe durch das Vakuum in den Ringraum bzw. in die Kokille eingebracht werden.Another problem that has not yet been solved satisfactorily in the known closed casting system is the supply of a lubricant into the mold. With the invention, a uniform supply of lubricant is made possible by the fact that a lubricant for the strand is introduced into this annular space by utilizing the vacuum in the annular space. Instead of a liquid, pasty or powdered lubricant, for example a non-oxidizing gas with or without additives can also be introduced into the annular space or into the mold by the vacuum.

Eine zusätzliche Verminderung des Verschleis- .ses am feuerfesten Verteilergefäss-Ausgussstutzen ist erreichbar, wenn, nach einem weiteren Merkmal der Erfindung, die elektromagnetische Spule beidseits der Verbindungsebene angeordnet ist.An additional reduction in wear on the refractory distributor spout can be achieved if, according to a further feature of the invention, the electromagnetic coil is arranged on both sides of the connection plane.

Zur Verminderung der Durchflussgeschwindigkeit des Metalles durch den Verteilergefäss-Ausgussstutzen und zur Erhöhung des Einschnüreffektes schlägt die Erfindung im weiteren vor, im Bereich der Verbindungsebene die Austrittsöffnung des Verteilergefäss-Ausgussstutzens und die Kokilleneintrittsöffnung gleich gross zu wählen sowie die Metallschmelze zusätzlich von der Austrittsöffnung mittels des elektromagnetischen Feldes fernzuhalten.In order to reduce the flow rate of the metal through the tundish spout and to increase the constriction effect, the invention further proposes to choose the outlet opening of the tundish spout and the mold inlet opening in the area of the connection level as well as the metal melt from the outlet opening by means of the electromagnetic Keep the field away.

Es kann vorteilhaft sein, wenn im Bereich der Verbindungsebene die Austrittsöffnung des Verteilergefäss-Ausgussstutzens kleiner als die Kokilleneintrittsöffnung ist.It can be advantageous if the outlet opening of the distribution vessel pouring spout is smaller than the mold inlet opening in the region of the connection plane.

Als eine weitere Ausgestaltung der Erfindung wird zur Beseitigung des Nachteiles des unterschiedlichen ferrostatischen Druckes beim Giessen von Strängen mit rundem Querschnitt die Anwendung einer ovalen oder einer exzentrisch angeordneten runden elektromagnetischen Spule vorgeschlagen, die unterhalb der horizontalen Längsachse der Kokille einen kleineren Abstand zum Kokillenhohlraum aufweist als oberhalb dieser Längsachse.As a further embodiment of the invention, in order to eliminate the disadvantage of the different ferrostatic pressure when casting strands with a round cross section, the use of an oval or an eccentrically arranged round electromagnetic coil is proposed, which has a smaller distance from the mold cavity below the horizontal longitudinal axis of the mold than above this longitudinal axis.

Die Güte der Strangoberfläche kann nach einem zusätzlichen Merkmal verbessert werden, wenn zwischen dem feuerfesten Verteilergefäss-Ausgusstutzen und der Durchlaufkokille ein Kokillenteil mit gegenüber der Durchlaufkokille reduzierter Wärmeleitfähigkeit angeordnet ist. Eine zusätzliche Verbesserung der einschnürenden Wirkung des elektromagnetischen Feldes im Formhohlraum kann erreicht werden, wenn der Kokillenteil aus paramagnetischem Werkstoff mit entsprechend niedriger Wärmeleitfähigkeit besteht.The quality of the strand surface can be improved according to an additional feature if a mold part with a reduced thermal conductivity compared to the flow mold is arranged between the refractory distribution vessel pouring spout and the flow mold. An additional improvement in the constricting effect of the electromagnetic field in the mold cavity can be achieved if the mold part consists of paramagnetic material with a correspondingly low thermal conductivity.

Im nachfolgenden werden anhand von Figuren Beispiele des Erfindungsgegenstandes erläutert.Examples of the subject matter of the invention are explained below with reference to figures.

Es zeigen:

  • Fig. 1 einen Vertikalschnitt durch einen Verteilergefäss-Ausgussstutzen und eine Durchlaufkokille,
  • Fig. 2 einen Schnitt nach der Linie IV-IV gemäss Fig. 1, und
  • Fig. 3 ein weiteres Beispiel einer Spulenanordnung.
Show it:
  • 1 is a vertical section through a tundish pouring spout and a continuous mold,
  • Fig. 2 is a section along the line IV-IV of FIG. 1, and
  • Fig. 3 shows another example of a coil arrangement.

In Fig. 1 ist ein feuerfester Verteilergefäss-Ausgussstutzen 2 mit einer gekühlten Durchlaufkokille 3 mit horizontaler Kokillenlängsachse 14 verbunden, was ein geschlossenes Eingiesssystem darstellt. Zwischen der Durchlaufkokille 3 und dem Verteilergefäss-Ausgussstutzen 2 befindet sich eine Verbindungsebene 4. Eine elektromagnetische Spule 16, die eine Einschnürung 7 des in die Durchlaufkokille 3 einfliessenden Stahles bewirkt, ist beidseits der Verbindungsebene 4 angeordnet. Dabei bildet sich ein freier Ringraum 8, so dass im Bereich der Verbindungsebene 4 der einfliessende Stahl die Kokille 3 noch nicht berühren kann. Der Verteilergefäss-Ausgussstutzen 2 ist ein Teil eines nicht dargestellten Verteilergefässes. Der Durchlaufkokille 3 folgen in der Regel nicht dargestellte, bekannte Stützführungselemente und ein Strangausziehaggregat für kontinuierlichen oder intermittierenden Strangauszug.In Fig. 1, a refractory distribution vessel pouring spout 2 is connected to a cooled continuous mold 3 with a horizontal longitudinal axis 14 of the mold, which represents a closed pouring system. A connection level 4 is located between the flow mold 3 and the distributor vessel pouring spout 2. An electromagnetic coil 16, which causes a constriction 7 of the steel flowing into the flow mold 3, is arranged on both sides of the connection level 4. A free annular space 8 is formed, so that the incoming steel cannot yet touch the mold 3 in the area of the connection plane 4. The distribution vessel pouring spout 2 is part of a distribution vessel, not shown. The continuous mold 3 is followed, as a rule, by known support guide elements (not shown) and a strand extraction unit for continuous or intermittent strand extraction.

In Fig. 2 ist eine Distanz 15 zwischen einer wassergekühlten, elektromagnetischen, einwindigen Spule 16 und dem Kokillenhohlraum 19 unterhalb der horizontalen Längsachse 14 der Durchlaufkokille 3 kleiner als eine Distanz 18 oberhalb der Längsachse 14. Auf der Eintrittsseite der Durchlaufkokille 3 ist ein Kokillenteil 20 mit einer Ausfütterung versehen, die gegenüber der Durchlaufkokille aus Kupfer eine reduzierte Wärmeleitfähigkeit aufweist. Diese Ausfütterung wird mit Vorteil aus paramagnetischem Werkstoff, z.B. rostfreiem Stahl, hergestellt. Damit sich in dem freien Ringraum 8 (Fig. 1) kein Vakuum bildet, das der Einschnürung 7 entgegenwirken würde, wird aus einem Behälter 22 über ein Druckreduzierventil 23 ein inertes Gas durch feine Zuführschlitze 24 in den Ringraum 8 zugeführt. Dieser Druck wird etwa dem atmosphärischen Druck angepasst und ist somit kleiner als derferrostatische Druck der Schmelze. Das Vakuum im Ringraum 8 kann auch zum Einbringen eines Schmiermittels für den Strang ausgenützt werden.In FIG. 2, a distance 15 between a water-cooled, electromagnetic, single-wind coil 16 and the mold cavity 19 below the horizontal longitudinal axis 14 of the continuous mold 3 is smaller than a distance 18 above the longitudinal axis 14. On the inlet side of the continuous mold 3 there is a mold part 20 a lining, which has a reduced thermal conductivity compared to the continuous mold made of copper. This lining is advantageously made of paramagnetic material, such as stainless steel. So that no vacuum forms in the free annular space 8 (FIG. 1), which would counteract the constriction 7, an inert gas is fed from a container 22 via a pressure reducing valve 23 through fine feed slots 24 into the annular space 8. This pressure is adjusted to the atmospheric pressure and is so with less than the ferrostatic pressure of the melt. The vacuum in the annular space 8 can also be used to introduce a lubricant for the strand.

In Fig. 3 ist eine schwach oval geformte elektromagnetische Spule 31 um einen runden Strangquerschnitt 32 angeordnet.3, a weakly oval-shaped electromagnetic coil 31 is arranged around a round strand cross section 32.

Die Auslegung der elektromagnetischen Spule und die Wahl der Leistung, der Frequenz usw. hat so zu erfolgen, dass im Bereich der Verbindungsebene die Metallschmelze von der Kokillenwand und/oder von der Verteilergefäss-Austrittsöffnung mittels eines einschnürenden elektromagnetischen Feldes ferngehalten wird. Zum Giessen eines runden Stranges von 100 mm 0 mittels einer Vorrichtung nach Fig. 3 können beispielsweise nachfolgende Parameter verwendet werden:

  • - Lichte Weite der Spule: 150 mm 0
  • -Anzahl Windungen: 1
  • - Spulenquerschnitt mit Innenkühlung: 36 x 36 mm
  • -Spulenmaterial: Kupfer
  • - Frequenz: 500 Hz
  • - Stromstärke: 4500 A
  • - Spannung: 10V
  • - Elektrische Wirkleistung: 34 W
The design of the electromagnetic coil and the choice of power, frequency etc. must be carried out in such a way that in the area of the connection level the metal melt is kept away from the mold wall and / or from the distributor vessel outlet opening by means of a constricting electromagnetic field. The following parameters can be used, for example, to cast a round strand of 100 mm 0 using a device according to FIG. 3:
  • - Clear width of the coil: 150 mm 0
  • - Number of turns: 1
  • - Coil cross-section with internal cooling: 36 x 36 mm
  • - Coil material: copper
  • - Frequency: 500 Hz
  • - Amperage: 4500 A.
  • - Voltage: 10V
  • - Active electrical power: 34 W.

Zum Giessen eines Vierkantstranges 150 mm 0 gemäss einer Vorrichtung nach den Fig. 1 und 2 werden nachfolgende Parameter empfohlen:

  • - Lichte Weite der Spule: 200 mm 0
  • - Anzahl Windungen: 1
  • - Spulenquerschnitt mit Innenkühlung: 30 x 40 mm
  • - Spulenmaterial: Kupfer
  • - Frequenz: 300 Hz
  • - Stromstärke: 5000 A
  • - Spannung: 15 V
  • - Elektrische Wirkleistung: 52,5 W
The following parameters are recommended for casting a square strand 150 mm 0 according to a device according to FIGS. 1 and 2:
  • - Clear width of the coil: 200 mm 0
  • - Number of turns: 1
  • - Coil cross-section with internal cooling: 30 x 40 mm
  • - Coil material: copper
  • - Frequency: 300 Hz
  • - Amperage: 5000 A.
  • - Voltage: 15 V.
  • - Active electrical power: 52.5 W.

Das erfindungsgemässe Verfahren und die Vorrichtung sind grundsätzlich für eine Vielzahl von Metallen anwendbar. Insbesondere können auch Eisen/Kohlenstoff-Legierungen gegossen werden. Durch die freie Gestaltungsmöglichkeit der Spule werden bei der Anwendung der Erfindung nur wenig Einschränkungen bezüglich unterschiedlicher Strangformate wirksam.The method and the device according to the invention can basically be used for a large number of metals. In particular, iron / carbon alloys can also be cast. Due to the free design possibility of the coil, only a few restrictions with regard to different strand formats are effective when using the invention.

Claims (8)

1. Equipment for the continuous casting of metal in a closed pouring system, wherein a refractory discharge port (2) of a distributor vesselais connected to a cooled open-ended mould (3), the longitudinal axis of which is substantially horizontal, characterized in that, in the zone of a connecting plane (4) between the discharge port (2) of the distributor vessel and the mould (3), there is arranged an electromagnetic coil (16, 31) which constricts the molten metal (13) and, between this coil (16, 31) and the mould cavity (19) below the substantially horizontal longitudinal axis (14) of the mould (3), there is a distance (15) that is less than a distance (18) above the longitudinal axis (14).
2. Equipment according to claim 1, characterized in that the electromagnetic coil (16) is arranged on that side of the connecting plane (4) on which the mould is located.
3. Equipment according to claim 1, characterized in that the electromagnetic coil (16,31) is arranged on both sides of the connecting plane (4).
4. Equipment according to one of claims 1 to 3, characterized in that, in the zone of the connecting plane (4), the outlet opening of the discharge port (2) of the distributor vessel and the mould inlet opening are of the same size.
5. Equipment according to one of claims 1 or 2, characterized in that, in the zone of the connecting plane (4), the outlet opening of the discharge port (2) of the distributor vessel is smaller than the mould inlet opening.
6. Equipment according to one of claims 1 to 5, characterized in that an oval electromagnetic coil (31 ) is provided.
7. Equipment according to one of claims 1 to 6, characterized in that, between the refractory discharge port (2) of the distributor vessel and the mould (3) made of copper, there is arranged a mould part (20) having thermal conductivity that is less than that of the copper rrould (3).
8. Equipment according to claim 7, characterized in that the mould part (20) of reduced thermal conductivity is made cf a paramagnetic material.
EP81105098A 1980-07-11 1981-07-01 Apparatus for the continuous casting of metal in a closed gating system Expired EP0043987B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81105098T ATE6476T1 (en) 1980-07-11 1981-07-01 DEVICE FOR CONTINUOUS CASTING OF METAL IN A CLOSED CASTING SYSTEM.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH5347/80A CH648500A5 (en) 1980-07-11 1980-07-11 METHOD AND DEVICE FOR CONTINUOUSLY casting metal in a closed pouring system.
CH5347/80 1980-07-11

Publications (2)

Publication Number Publication Date
EP0043987A1 EP0043987A1 (en) 1982-01-20
EP0043987B1 true EP0043987B1 (en) 1984-03-07

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EP81105098A Expired EP0043987B1 (en) 1980-07-11 1981-07-01 Apparatus for the continuous casting of metal in a closed gating system

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US (1) US4450892A (en)
EP (1) EP0043987B1 (en)
JP (1) JPS5744454A (en)
KR (1) KR840002039B1 (en)
AT (1) ATE6476T1 (en)
BR (1) BR8104428A (en)
CA (1) CA1176427A (en)
CH (1) CH648500A5 (en)
DE (1) DE3162508D1 (en)
ES (1) ES8205141A1 (en)

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JPS57209752A (en) * 1981-06-17 1982-12-23 Kawasaki Heavy Ind Ltd Horizontal continuous casting installation
DE3131353A1 (en) * 1981-08-07 1983-02-24 Neue Technik Entwicklung und Vertrieb F. Block, 5106 Roetgen "METHOD AND DEVICE FOR SEALING THE GAP BETWEEN RELATIVELY MOVING DEVICES"
DE3136847C1 (en) * 1981-09-16 1982-10-28 Korf Engineering GmbH, 4000 Düsseldorf Method and device for horizontal continuous casting of liquid metals, in particular steel
JPS5886959A (en) * 1981-11-18 1983-05-24 Kawasaki Heavy Ind Ltd Horizontal continuous casting method
KR870000714B1 (en) * 1981-11-18 1987-04-09 하세가와 겐고오 Horizontal continuous casting method
CH665369A5 (en) * 1984-03-07 1988-05-13 Concast Standard Ag METHOD FOR CONTROLLING THE FLOW OF A METAL MELT IN CONTINUOUS CASTING, AND A DEVICE FOR IMPLEMENTING THE METHOD.
JPS61111747A (en) * 1984-11-07 1986-05-29 Nippon Kokan Kk <Nkk> Continuous casting device for steel plate
JPS61186150A (en) * 1985-02-13 1986-08-19 Sumitomo Light Metal Ind Ltd Casting method by suspension in electromagnetic field
US4693299A (en) * 1986-06-05 1987-09-15 Westinghouse Electric Corp. Continuous metal casting apparatus
US4741383A (en) * 1986-06-10 1988-05-03 The United States Of America As Represented By The United States Department Of Energy Horizontal electromagnetic casting of thin metal sheets
US4842170A (en) * 1987-07-06 1989-06-27 Westinghouse Electric Corp. Liquid metal electromagnetic flow control device incorporating a pumping action
US4846255A (en) * 1987-10-28 1989-07-11 The United States Of America As Represented By The United States Department Of Energy Electromagnetic augmentation for casting of thin metal sheets
JPH04197559A (en) * 1990-11-27 1992-07-17 Nkk Corp Continuous casting method for steel
US5379828A (en) * 1990-12-10 1995-01-10 Inland Steel Company Apparatus and method for continuous casting of molten steel
US5494095A (en) * 1992-04-08 1996-02-27 Inland Steel Company Apparatus for continuous casting of molten steel
IT1316299B1 (en) * 2000-01-26 2003-04-10 Danieli Off Mecc PROCEDURE AND DEVICE TO IMPROVE THE QUALITY OF CONTINUOUSLY CAST CASTINGS
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KR830005941A (en) 1983-09-14
ES504334A0 (en) 1982-06-01
JPS5744454A (en) 1982-03-12
ES8205141A1 (en) 1982-06-01
EP0043987A1 (en) 1982-01-20
US4450892A (en) 1984-05-29
BR8104428A (en) 1982-03-30
CA1176427A (en) 1984-10-23
KR840002039B1 (en) 1984-11-06
CH648500A5 (en) 1985-03-29
ATE6476T1 (en) 1984-03-15
DE3162508D1 (en) 1984-04-12
JPS6257420B2 (en) 1987-12-01

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