EP0114309B1 - Method of and apparatus for sealing a dummy bar head in a continuous-casting mold - Google Patents

Method of and apparatus for sealing a dummy bar head in a continuous-casting mold Download PDF

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Publication number
EP0114309B1
EP0114309B1 EP83112670A EP83112670A EP0114309B1 EP 0114309 B1 EP0114309 B1 EP 0114309B1 EP 83112670 A EP83112670 A EP 83112670A EP 83112670 A EP83112670 A EP 83112670A EP 0114309 B1 EP0114309 B1 EP 0114309B1
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EP
European Patent Office
Prior art keywords
seal
bar head
mould
dummy bar
seal retainer
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
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EP83112670A
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German (de)
French (fr)
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EP0114309A1 (en
Inventor
Carlos Ros Navarro
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Concast Standard AG
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Concast Standard AG
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Publication date
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Publication of EP0114309A1 publication Critical patent/EP0114309A1/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
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/08—Accessories for starting the casting procedure
    • B22D11/088—Means for sealing the starter bar head in the moulds

Definitions

  • the invention relates to a method for moving a start-up head and for sealing the gap between the start-up head and a continuous casting mold, in particular when casting steel on multi-strand systems, the starting head being provided with a seal before entering the mold and a device for sealing.
  • the start-up head connected to the start-up strand is moved into the mold before the start of casting.
  • the gap between the start-up head and the mold walls is sealed with a sealing cord or with a plastic mass etc. and is usually covered with fine-grained cooling scrap.
  • the invention has for its object to provide a method for moving the start-up head into a mold and for sealing the gap between the start-up head and the mold and a sealing device that the known manual sealing work between the start-up head and the mold as well as visual controls by the pouring side Switch off the mold opening.
  • the time required to prepare the mold before the start of casting is also to be shortened, and safe and quick restarting in multi-strand systems, with casting on neighboring strands, is to be made possible, with previous starting heads being used for manual sealing.
  • the method according to the invention and the device according to the invention make it possible to dispense with the manual sealing work on the starting head in the mold and visual checks through the mold-side mold opening. Therefore, the preparation time of the continuous caster between two castings is reduced.
  • This sealing system also makes it possible to restart after a breakthrough on one strand of a multi-strand system while casting is in progress on neighboring strands. With long-lasting sequence castings, this restart ensures high throughput rates even in multi-strand systems with small casting formats at risk of breakthrough. Common starting heads can be used without changes.
  • the destructible seal holder is cheap to manufacture and material.
  • the seal can be attached to the seal holder before it is placed on the start-up head or after the seal holder has been placed on the start-up head.
  • the second embodiment is used in particular when a seal with plastic sealing material is used. This usually water-free plastic sealing material can be pressed in sausage form between the sealing surface on the start-up head and the corresponding fastening surface on the seal holder.
  • the seal on the seal holder is such is attached that this corresponds in its geometric cross-sectional shape essentially to the sealing surface of the start head. This can be ensured, for example, by using an appropriate teaching. Furthermore, it is advantageous if the fastening surface for the seal on the seal holder is essentially matched in its geometric shape to the sealing surface of the start-up head and to the type and dimensioning of the seal.
  • the seal is glued to the seal holder.
  • the seal holder can consist of an elastically deformable material and its cross section can be selected to be somewhat larger than the mold cavity cross section of the mold .
  • the seal holder and the seal are deformed to a circumference corresponding to the mold cross section.
  • the seal holder can be provided with holding and centering devices opposite the start-up head.
  • the coupling device on the start-up head for the cast strand can be used, for example, as a holding and centering device.
  • the seal holder can be destroyed by the pouring casting metal in a variety of ways. If the seal holder is made of aluminum, it will be destroyed by melting. Is the seal holder made of gasifiable plastic foam, e.g. B. from foamed polystyrene, this body disappears through gasification.
  • gasifiable plastic foam e.g. B. from foamed polystyrene
  • the seal holder can, according to one embodiment, be approximately pyramid-shaped. This allows an optional application of granular cooling scrap.
  • the seal holder can also be composed of different materials.
  • a gasifiable seal holder is described, which is combined with sheet metal strips which cover the seal against the mold walls.
  • sheet metal strips are advantageously arranged in such a way that when they enter the mold they shift towards the longitudinal axis of the mold and can therefore automatically compensate for irregular gap widths when viewed across the mold cross section.
  • scratches on the mold wall at the entrance can be avoided.
  • the seal holder can be placed in the area below the mold shortly before the start-up head enters the mold.
  • a starting head 3 which is connected to a starting line 4, is in the casting position in a continuous casting mold 2.
  • a seal 6 in the form of a paper or asbestos cord etc. is provided for sealing between the starting head 3 and the mold 2.
  • the geometrical shape of the fastening surface 11 is essentially matched to the sealing surface 13 of the starting head 3 and to the type and dimensions of the seal 6.
  • the seal holder 10 is provided with a holding and centering device 14 opposite the start-up head 3 in the manner of a dovetail body.
  • a steel baffle plate 16 attached to the seal holder 10 protects the point of impact of the pouring jet at the start of the pouring head 3 so that granular cooling scrap 17 is distributed over the seal 6, the seal holder 10 is pyramid-shaped.
  • seal holder 10 is made of gasifiable plastic, for. B. from foamed polystyrene, which is gasified by the heat of the incoming cast metal.
  • gasifiable plastic for. B. from foamed polystyrene, which is gasified by the heat of the incoming cast metal.
  • polystyrene any other flammable, gasifiable, fusible substance can be used. It is important that the coupling part of the start-up head 3 can form a non-positive connection with the pouring metal immediately after the start of casting.
  • a seal holder 20 is shown, which is slightly larger in cross-section 21 than the corresponding cross-section 22 of the mold cavity 7.
  • the seal 6 attached to the seal holder 20 is covered with sheet metal strips 24, which in the sides 25 of the seal holder opposite the mold walls 20 are inserted.
  • these metal strips which are made of soft aluminum, for example, move in the seal holder in the direction of arrow 27, so that a snug fit against the mold wall is ensured.
  • a seal holder 30 is preformed from thin sheet metal, for example from aluminum sheet.
  • the seal 6 and the baffle plate 16 and a centering device 14 are attached to the sheet-shaped seal holder 30.
  • the pyramid-shaped part 31 is optional and is only necessary if cooling scrap is applied to this starting head 33 with an inclined end face 34.
  • This seal holder 30 is also produced in cross section with advantage compared to the cross section of the mold cavity 7, as shown by dimensional arrows 36 so that the seal and the seal holder 30 are fixed in the mold 2 by clamping.
  • the starting head 3 is provided with a coupling part 41.
  • a sheet-like seal 43 made of, for example, a thermally resistant fabric essentially covers the entire surface 44 facing the mold cavity 7 of the mold and part of the lateral boundary surfaces 46 of the start-up head 3 that abut against this surface 44.
  • This layered seal 43 also has a sealing function in addition to the sealing function protection for the starting head 3 and thereby extends the service life of such starting heads 3.
  • a protruding nose 47 is connected to a baffle plate 16 made of metal and fixes a seal holder 40, provided at least in the area of the sealing edge 49, together with the seal 43 relative to the starting head 3.
  • the seal holder 40 made of injection molded plastic, such as polyethylene, is placed in a cap shape over the start-up head.
  • the seal holder 40, the baffle plate 16 and the layered seal 43 are generally attached to one another before being placed on the starting head.
  • Such prefabricated sealing units can be placed on corresponding start-up heads 3 with a handle or in a few seconds.
  • the seal holder 40 can have a certain elasticity, so that the entire seal unit can be clamped on the starting head 3. Thanks to the elasticity, even small dimensional differences between different start heads can be compensated.
  • seal holder 40 Another advantage of this seal holder 40 is the good protection of the seal 43 and the start-up head 3 against water drops from spray nozzles and against moisture. It is clear that the plastic seal holder 40 prevents direct contact between the metallic part of the start-up head and the mold cavity 7 of the mold and thus reduces mold wear.
  • the layered seal 43 can consist of different materials. Their main task is to close the gap between the start-up head 3 and the cooled mold wall during a few seconds after casting, i.e. until the steel has solidified above the gap due to the intensive mold cooling.
  • the sealing system according to the invention can be used in billet, bloom, slab, billet molds, etc.
  • the seal holder for large molds can also only be frame-shaped and essentially only follow the contour of the sealing surface. There are also no restrictions within the scope of the claims with regard to the materials for the seal holder and for the seal.
  • the casting performance can be adapted to an irregular steel delivery caused by a fault by deliberately interrupting the casting and restarting individual strands.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Moulds For Moulding Plastics Or The Like (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Continuous Casting (AREA)

Description

Die Erfindung betrifft ein Verfahren zum Einfahren eines Anfahrkopfes und zum Abdichten des Spaltes zwischen dem Anfahrkopf und einer Stranggiesskokille, insbesondere beim Giessen von Stahl auf Mehrstranganlagen, wobei der Anfahrkopf vor der Einfahrt in die Kokille mit einer Dichtung versehen wird und eine Einrichtung zum Abdichten.The invention relates to a method for moving a start-up head and for sealing the gap between the start-up head and a continuous casting mold, in particular when casting steel on multi-strand systems, the starting head being provided with a seal before entering the mold and a device for sealing.

Bei Stranggiessanlagen mit Durchlaufkokillen wird vor Giessbeginn der mit dem Anfahrstrang verbundene Anfahrkopf in die Kokille eingefahren. Der Spalt zwischen dem Anfahrkopf und den Kokillenwänden wird mit einer Dichtungsschnur oder mit einer plastischen Masse etc. abgedichtet und in der Regel mittels feinkörnigem Kühlschrott abgedeckt. Dem bei Giessbeginn einfliessenden Giessmetall wird durch diese Massnahmen ein unerwünschter Austritt durch den genannten Spalt verwehrt. Das Einbringen der Dichtung erfolgt durch die eingiessseitige Kokillenöffnung. Dieses in der Praxis des Stahlstranggiessens weit verbreitete Abdichtverfahren hat den Nachteil, dass nach der Einfahrt des Anfahrkopfes in die Kokille zusätzlich Zeit für Abdichtarbeiten benötigt wird, wodurch die Vorbereitungszeit der Anlage zwischen zwei Güssen verlängert wird. Bei Mehrstranganlagen können nach einem Durchbruch auf einem Strang die Abdichtarbeiten für ein Wiedereinfahren bei laufendem Guss auf den restlichen Strängen nicht durchgeführt werden, weil das oberhalb der Kokille angeordnete Zwischengefäss einerseits die Zugänglichkeit behindert und anderseits wegen Unfallgefährdung nicht unter einem mit flüssigem Stahl gefüllten Zwischengefäss gearbeitet werden soll.In continuous casting plants with continuous molds, the start-up head connected to the start-up strand is moved into the mold before the start of casting. The gap between the start-up head and the mold walls is sealed with a sealing cord or with a plastic mass etc. and is usually covered with fine-grained cooling scrap. These measures prevent the casting metal flowing in at the start of casting from undesired escape through the gap mentioned. The seal is inserted through the mold-side mold opening. This sealing process, which is widespread in the practice of continuous steel casting, has the disadvantage that additional time is required for sealing work after the start-up head has entered the mold, which extends the preparation time of the system between two castings. In the case of multi-strand systems, after a breakthrough on one strand, the sealing work for re-entry while the casting is running cannot be carried out on the remaining strands because the intermediate vessel located above the mold on the one hand impedes access and, on the other hand, because of the risk of accidents, the intermediate vessel cannot be operated under an intermediate vessel filled with liquid steel should.

Um die manuellen Dichtarbeiten, die in ihrer Qualität wesentlich von Sorgfalt und Geschicklichkeit des die Dichtung anbringenden Arbeiters abhängt, auszuschalten, ist aus der, den Oberbegriff der Ansprüche 1 und 8 bildenden AT-PS 352 924 ein Anfahrkopf mit einer Flachdichtung bekannt, die zusammen mit einem Federblatt in eine, in der Stirnseite des Anfahrkopfes eingelassene, Nut eingeschoben wird. Diese Flachdichtung wird vor der Einfahrt des Anfahrkopfes in die Kokille am Anfahrkopf angebracht. Dieses Verfahren hat den Nachteil, dass die Dichtung eine genau zentrische Einfahrt des Anfahrkopfes in den Kokillenhohlraum erfordert, damit einerseits die Dichtung nicht zerstört wird und anderseits keine Spalte entstehen. Im weiteren muss die Dichtung durch entsprechend dicke Schichten von Kühlschrott gegen die Wärmeeinwirkung des flüssigen Stahles geschützt werden, damit sie nicht verbrennt. Bei Nichterfüllung eines dieser beiden Erfordernisse kann beim Angiessen Stahl aus dem Spalt austreten, was in der Regel zu einem Gussabbruch führt.In order to switch off the manual sealing work, the quality of which essentially depends on the care and skill of the worker applying the seal, from AT-PS 352 924, which forms the preamble of claims 1 and 8, a starting head with a flat seal is known, which together with a spring leaf is inserted into a groove in the front of the start-up head. This flat seal is attached to the start-up head before the start-up head enters the mold. This method has the disadvantage that the seal requires a precisely central entry of the start-up head into the mold cavity, so that on the one hand the seal is not destroyed and on the other hand there are no gaps. Furthermore, the seal must be protected against the heat of the liquid steel by layers of cooling scrap, so that it does not burn. If one of these two requirements is not met, steel can escape from the gap during casting, which usually leads to a casting break.

Es ist weiter aus der DE-OS 2 811 157 ein Verfahren zum Abdichten des Spaltes zwischen dem Anfahrkopf und einer Stranggiesskokille bekannt, wobei der Anfahrkopf mit einer ringförmigen Nut an seinem Umfang versehen ist, in welche vor der Einfahrt in die Kokille eine elastische Dichtung eingesetzt wird. Die Dichtung kann schlauchförmig und mit einem gasförmigen Medium aufblasbar sein. Bei diesem Dichtungssystem muss von der Kokillenoberseite durch Einbringen von feinkörnigem Kühlschrott die elastische Dichtung auf ihrem ganzen Umfang geschützt werden, damit sie vom einfliessenden Stahl nicht zerstört und/ oder die Nut vergossen wird. Ohne visuelle Kontrolle der lückenlosen Auffüllung des Spaltes oberhalb der Dichtung mit Kühlschrott besteht auch bei diesem Abdichtverfahren eine Gefahr für Anfahrdurchbrüche. Ein sicheres Wiederanfahren bei Mehrstranganlagen bei laufendem Guss ist mit diesem Verfahren nicht zuverlässig erreichbar.It is also known from DE-OS 2 811 157 a method for sealing the gap between the start-up head and a continuous casting mold, the start-up head being provided with an annular groove on its circumference, into which an elastic seal is inserted before entering the mold becomes. The seal can be tubular and inflatable with a gaseous medium. In this sealing system, the entire circumference of the elastic seal must be protected from the upper side of the mold by introducing fine-grained cooling scrap so that it is not destroyed by the incoming steel and / or the groove is cast. Without visual inspection of the gap-free filling of the gap above the seal with cooling scrap, there is also a risk of breakouts in this sealing process. A reliable restart in multi-strand systems with the casting in progress cannot be reliably achieved with this method.

Der Erfindung liegt die Aufgabe zugrunde, ein Verfahren zum Einfahren des Anfahrkopfes in eine Kokille und zum Abdichten des Spaltes zwischen dem Anfahrkopf und der Kokille und eine Abdichteinrichtung zu schaffen, die die bekannten manuellen Abdichtarbeiten zwischen dem Anfahrkopf und der Kokille sowie visuelle Kontrollen durch die eingiesseitige Kokillenöffnung ausschalten. Auch soll die erforderliche Zeit zum Vorbereiten der Kokille vor Giessbeginn verkürzt und ein sicheres und schnelles Wiederanfahren bei Mehrstranganlagen, bei laufendem Guss auf Nachbarsträngen, ermöglicht werden, wobei bisher übliche Anfahrköpfe für manuelle Abdichtung verwendbar sein sollen.The invention has for its object to provide a method for moving the start-up head into a mold and for sealing the gap between the start-up head and the mold and a sealing device that the known manual sealing work between the start-up head and the mold as well as visual controls by the pouring side Switch off the mold opening. The time required to prepare the mold before the start of casting is also to be shortened, and safe and quick restarting in multi-strand systems, with casting on neighboring strands, is to be made possible, with previous starting heads being used for manual sealing.

Gemäss der Erfindung wird diese Aufgabe durch die Merkmale des Verfahrensanspruches 1 und des Vorrichtungsanspruches 8 gelöst.According to the invention, this object is achieved by the features of method claim 1 and device claim 8.

Das erfindungsgemässe Verfahren bzw. die erfindungsgemässe Vorrichtung ermöglichen es, auf die manuellen Abdichtarbeiten am Anfahrkopf in der Kokille und visuelle Kontrollen durch die eingiesseitige Kokillenöffnung zu verzichten. Daher verkürzt sich die Vorbereitungszeit der Stranggiessanlage zwischen zwei Güssen. Auch ein Wiederanfahren nach einem Durchbruch auf einem Strang einer Mehrstranganlage bei laufendem Guss auf Nachbarsträngen wird durch dieses Abdicht-System ermöglicht. Dieses Wiederanfahren stellt bei langdauernden Sequenzgüssen hohe Durchsatzleistungen auch bei Mehrstranganlagen mit durchbruchgefährdeten kleinen Giessformaten sicher. Bisher übliche Anfahrköpfe können ohne Änderungen verwendet werden. Der zerstörbare Dichtungshalter ist in seiner Herstellung und vom Material her billig.The method according to the invention and the device according to the invention make it possible to dispense with the manual sealing work on the starting head in the mold and visual checks through the mold-side mold opening. Therefore, the preparation time of the continuous caster between two castings is reduced. This sealing system also makes it possible to restart after a breakthrough on one strand of a multi-strand system while casting is in progress on neighboring strands. With long-lasting sequence castings, this restart ensures high throughput rates even in multi-strand systems with small casting formats at risk of breakthrough. Common starting heads can be used without changes. The destructible seal holder is cheap to manufacture and material.

Je nach Wahl des Dichtungsmaterials kann die Dichtung am Dichtungshalter vor dem Aufsetzen auf den Anfahrkopf befestigt oder nach dem Aufsetzen des Dichtungshalters auf den Anfahrkopf angebracht werden. Die zweite Ausgestaltung wird insbesondere dann angewendet, wenn eine Dichtung mit plastischem Dichtungsmaterial verwendet wird. Dieses in der Regel wasserfreie plastische Dichtungsmaterial kann in Wurstform zwischen die Dichtungsfläche am Anfahrkopf und die entsprechende Befestigungsfläche am Dichtungshalter eingedrückt werden.Depending on the choice of sealing material, the seal can be attached to the seal holder before it is placed on the start-up head or after the seal holder has been placed on the start-up head. The second embodiment is used in particular when a seal with plastic sealing material is used. This usually water-free plastic sealing material can be pressed in sausage form between the sealing surface on the start-up head and the corresponding fastening surface on the seal holder.

Bei schnurförmigen Dichtungen ist es von Vorteil, wenn die Dichtung am Dichtungshalter derart befestigt wird, dass diese in ihrer geometrischen Querschnittsform im wesentlichen der Abdichtfläche des Anfahrkopfes entspricht. Dies kann beispielsweise durch Verwendung einer entsprechenden Lehre sichergestellt werden. Im weitern ist es von Vorteil, wenn die Befestigungsfläche für die Dichtung am Dichtungshalter in ihrer geometrischen Form im wesentlichen auf die Abdichtfläche des Anfahrkopfes und auf die Art sowie Dimensionierung der Dichtung abgestimmt ist.With cord-shaped seals, it is advantageous if the seal on the seal holder is such is attached that this corresponds in its geometric cross-sectional shape essentially to the sealing surface of the start head. This can be ensured, for example, by using an appropriate teaching. Furthermore, it is advantageous if the fastening surface for the seal on the seal holder is essentially matched in its geometric shape to the sealing surface of the start-up head and to the type and dimensioning of the seal.

Wird als Dichtung eine Asbest- oder Papierschnur etc. verwendet, so ist es von Vorteil, wenn die Dichtung am Dichtungshalter angeklebt wird.If an asbestos or paper cord etc. is used as the seal, it is advantageous if the seal is glued to the seal holder.

Damit während der Einfahrt ein bestimmter Druck auf die Dichtung aufgebracht und diese wiederum gegen die Abdichtfläche des Anfahrkopfes gedrückt wird, kann gemäss einer weiteren Ausgestaltung der Dichtungshalter aus einem elastisch verformbaren Material bestehen und in seinem Querschnitt etwas grösser als der Formhohlraum-Querschnitt der Kokille gewählt werden. Bei der Einfahrt in die Kokille wird der Dichtungshalter und die Dichtung auf einen dem Kokillen-Querschnitt entsprechenden Umfang verformt.So that a certain pressure is applied to the seal during the entry and this in turn is pressed against the sealing surface of the start-up head, according to a further embodiment the seal holder can consist of an elastically deformable material and its cross section can be selected to be somewhat larger than the mold cavity cross section of the mold . When entering the mold, the seal holder and the seal are deformed to a circumference corresponding to the mold cross section.

Zum Schutze des Anfahrkopfes wird vorgeschlagen, vor der Einfahrt des Anfahrkopfes in die Kokille am Dichtungshalter in der Auftreffzone des einfliessenden Giessmetalles eine Prallplatte aus Stahl zu befestigen.To protect the start-up head, it is proposed to fasten a steel baffle plate on the seal holder in the impact zone of the incoming cast metal before the start-up head enters the mold.

Um ein rasches Befestigen des Dichtungshalters auf dem Anfahrkopf sicherzustellen, kann, nach einer weiteren Ausführungsform, der Dichtungshalter mit Halte- und Zentriereinrichtungen gegenüber dem Anfahrkopf versehen sein. Als Halte- und Zentriereinrichtung kann beispielsweise die Kupplungseinrichtung am Anfahrkopf für den gegossenen Strang verwendet werden.In order to ensure a quick fastening of the seal holder on the start-up head, according to a further embodiment, the seal holder can be provided with holding and centering devices opposite the start-up head. The coupling device on the start-up head for the cast strand can be used, for example, as a holding and centering device.

Die Zerstörung des Dichtungshalters durch das einfliessende Giessmetall kann auf verschiedenste Weise vonstatten gehen. Besteht der Dichtungshalter aus Aluminium, so wird er durch Aufschmelzen zerstört. Besteht der Dichtungshalter aus vergasbarem Kunststoff-Schaum, z. B. aus geschäumten Polystyrol, so verschwindet dieser Körper durch Vergasung.The seal holder can be destroyed by the pouring casting metal in a variety of ways. If the seal holder is made of aluminum, it will be destroyed by melting. Is the seal holder made of gasifiable plastic foam, e.g. B. from foamed polystyrene, this body disappears through gasification.

Zur Erreichung einer idealen Verteilung des Kühlschrottes zur Abdeckung der Dichtung nach der Zerstörung des Dichtungshalters, kann, nach einer Ausgestaltung, der Dichtungshalter etwa pyramidenförmig ausgebildet sein. Dies erlaubt eine fakultative Anwendung von körnigem Kühlschrott.In order to achieve an ideal distribution of the cooling scrap for covering the seal after the seal holder has been destroyed, the seal holder can, according to one embodiment, be approximately pyramid-shaped. This allows an optional application of granular cooling scrap.

Der Dichtungshalter kann aber auch aus verschiedenen Materialien zusammengesetzt sein. Um ein Beispiel aus den vielfältigen Variationsmöglichkeiten zu erwähnen, wird ein vergasbarer Dichtungshalter beschrieben, der mit Blechstreifen kombiniert ist, welche die Dichtung gegen die Kokillenwände hin überdecken. Solche Blechstreifen werden mit Vorteil so angeordnet, dass sie bei der Einfahrt in die Kokille sich zur Kokillenlängsachse hin verschieben und dadurch über den Kokillenquerschnitt gesehen unregelmässige Spaltbreiten selbsttätig ausgleichen können. Bei Verwendung von Aluminium für solche Blechstreifen können Kratzer an der Kokillenwand bei der Einfahrt vermieden werden.The seal holder can also be composed of different materials. In order to mention an example from the various possible variations, a gasifiable seal holder is described, which is combined with sheet metal strips which cover the seal against the mold walls. Such sheet metal strips are advantageously arranged in such a way that when they enter the mold they shift towards the longitudinal axis of the mold and can therefore automatically compensate for irregular gap widths when viewed across the mold cross section. When using aluminum for such metal strips, scratches on the mold wall at the entrance can be avoided.

Sind bei Mehrstranganlagen die Kühlkammern der einzelnen Stränge gegeneinander durch Trennwände geteilt, so kann der Dichtungshalter im Bereich unterhalb der Kokille kurz vor der Einfahrt des Anfahrkopfes in die Kokille aufgesetzt werden.If the cooling chambers of the individual strands are divided from one another by partitions in multi-strand systems, the seal holder can be placed in the area below the mold shortly before the start-up head enters the mold.

Die Erfindung wird anhand mehrerer Ausführungsformen näher erläutert. Es zeigen:

  • Fig. 1 einen Vertikalschnitt durch eine Kokille mit eingesetztem Anfahrkopf,
  • Fig. 2 einen Vertikalschnitt durch eine Kokille und einen Anfahrkopf eines weiteren Beispiels kurz vor der Einfahrt in die Kokille,
  • Fig. einen Vertikalschnitt durch eine Kokille und einen Anfahrkopf eines anderen Beispieles kurz vor der Einfahrt in die Kokille und
  • Fig. 4 einen Vertikalschnitt durch einen Anfahrkopf eines weiteren Beispieles.
The invention is explained in more detail using several embodiments. Show it:
  • 1 is a vertical section through a mold with the start-up head inserted,
  • 2 shows a vertical section through a mold and a start-up head of a further example shortly before entering the mold,
  • Fig. A vertical section through a mold and a start head of another example just before entering the mold and
  • Fig. 4 is a vertical section through a start head of another example.

In Fig. 1 ist in einer Stranggiesskokille 2 ein Anfahrkopf 3, der mit einem Anfahrstrang 4 verbunden ist, in Angiessposition. Zur Abdichtung zwischen dem Anfahrkopf 3 und der Kokille 2 ist eine Dichtung 6 in Form einer Papier- oder Asbestschnur etc. vorgesehen. Auf der dem Formhohlraum 7 der Kokille 2 zugekehrten Stirnseite 9 des Anfahrkopfes 3 ist ein zerstörbarer Dichtungshalter 10, der eine Befestigungsfläche 11 für die Dichtung 6 aufweist, vorgesehen. Die Dichtung 6 ist zwischen einer Dichtungsfläche 13 am Anfahrkopf 3 und der Befestigungsfläche 11 sowie zwischen der Kokillenwand eingeklemmt. Die Befestigungsfläche 11 ist in ihrer geometrischen Form im wesentlichen auf die Dichtungsfläche 13 des Anfahrkopfes 3 sowie auf die Art und die Dimensionierung der Dichtung 6 abgestimmt.In Fig. 1, a starting head 3, which is connected to a starting line 4, is in the casting position in a continuous casting mold 2. A seal 6 in the form of a paper or asbestos cord etc. is provided for sealing between the starting head 3 and the mold 2. A destructible seal holder 10, which has a fastening surface 11 for the seal 6, is provided on the end face 9 of the starting head 3 facing the mold cavity 7 of the mold 2. The seal 6 is clamped between a sealing surface 13 on the starting head 3 and the fastening surface 11 and between the mold wall. The geometrical shape of the fastening surface 11 is essentially matched to the sealing surface 13 of the starting head 3 and to the type and dimensions of the seal 6.

Der Dichtungshalter 10 ist mit einer Halte- und Zentriereinrichtung 14 gegenüber dem Anfahrkopf 3 in der Art eines Schwalbenschwanzkörpers versehen. Eine am Dichtungshalter 10 befestigte Prallplatte 16 aus Stahl schützt den Auftreffpunkt des Giessstrahles bei Giessbeginn am Anfahrkopf 3. Damit sich körniger Kühlschrott 17 über die Dichtung 6 verteilt, ist der Dichtungshalter 10 pyramidenförmig.The seal holder 10 is provided with a holding and centering device 14 opposite the start-up head 3 in the manner of a dovetail body. A steel baffle plate 16 attached to the seal holder 10 protects the point of impact of the pouring jet at the start of the pouring head 3 so that granular cooling scrap 17 is distributed over the seal 6, the seal holder 10 is pyramid-shaped.

Der in diesem Beispiel vorgesehene Dichtungshalter 10 ist aus vergasbarem Kunststoff, z. B. aus geschäumtem Polystyrol, der durch die Wärmeeinwirkung des einfliessenden Giessmetalles vergast wird. Anstelle von Polystyrol kann jeder andere brennbare, vergasbare, schmelzbare Stoff verwendet werden. Wichtig ist, dass der Kupplungsteil des Anfahrkopfes 3 mit dem einfliessenden Giessmetall sofort nach Giessbeginn eine kraftschlüssige Verbindung bilden kann.The provided in this example seal holder 10 is made of gasifiable plastic, for. B. from foamed polystyrene, which is gasified by the heat of the incoming cast metal. Instead of polystyrene, any other flammable, gasifiable, fusible substance can be used. It is important that the coupling part of the start-up head 3 can form a non-positive connection with the pouring metal immediately after the start of casting.

In Fig. 2 ist ein Dichtungshalter 20 dargestellt, der in seinem Querschnitt 21 etwas grösser ist als der entsprechende Querschnitt 22 des Formhohlraumes 7. Die am Dichtungshalter 20 befestigte Dichtung 6 ist mit Blechstreifen 24 überdeckt, die in die den Kokillenwänden gegenüberliegenden Seiten 25 des Dichtungshalters 20 eingesteckt sind. Beim Einfahren des Anfahrkopfes 3 können sich diese Blechstreifen, die beispielsweise aus weichem Aluminium sind, im Dichtungshalter in Pfeilrichtung 27 verschieben, so dass ein sattes Anliegen an der Kokillenwand gewährleistet ist.In Fig. 2, a seal holder 20 is shown, which is slightly larger in cross-section 21 than the corresponding cross-section 22 of the mold cavity 7. The seal 6 attached to the seal holder 20 is covered with sheet metal strips 24, which in the sides 25 of the seal holder opposite the mold walls 20 are inserted. When retracting the head 3 can these metal strips, which are made of soft aluminum, for example, move in the seal holder in the direction of arrow 27, so that a snug fit against the mold wall is ensured.

In Fig. 3 ist ein Dichtungshalter 30 aus dünnem Blech vorgeformt, beispielsweise aus AluminiumBlech. Die Dichtung 6 und die Prallplatte 16 sowie eine Zentriereinrichtung 14 sind am blechförmigen Dichtungshalter 30 befestigt. Der pyramidenförmige Teil 31 ist in diesem Beispiel fakultativ und nur dann notwendig, wenn bei diesem Anfahrkopf 33 mit schräger Stirnseite 34 Kühlschrott aufgebracht wird. Auch dieser Dichtungshalter 30 wird im Querschnitt mit Vorteil gegenüber dem Querschnitt des Formhohlraumes 7 etwas grösser gefertigt, wie durch Masspfeile 36 dargestellt, damit die Dichtung und der Dichtungshalter 30 in der Kokille 2 durch Klemmung fixiert werden.3, a seal holder 30 is preformed from thin sheet metal, for example from aluminum sheet. The seal 6 and the baffle plate 16 and a centering device 14 are attached to the sheet-shaped seal holder 30. In this example, the pyramid-shaped part 31 is optional and is only necessary if cooling scrap is applied to this starting head 33 with an inclined end face 34. This seal holder 30 is also produced in cross section with advantage compared to the cross section of the mold cavity 7, as shown by dimensional arrows 36 so that the seal and the seal holder 30 are fixed in the mold 2 by clamping.

In Fig. 4 ist der Anfahrkopf 3 mit einem Kupplungsteil 41 versehen. Eine flächenförmige Dichtung 43 aus beispielsweise einem thermisch widerstandsfähigen Gewebe überdeckt im wesentlichen die gesamte, dem Formhohlraum 7 der Kokille zugekehrte Fläche 44 und einen Teil der an diese Fläche 44 anstossenden seitlichen Begrenzungsflächen 46 des Anfahrkopfes 3. Diese schichtförmig angeordnete Dichtung 43 bewirkt neben der Dichtungsfunktion auch einen Schutz für den Anfahrkopf 3 und verlängert dadurch die Standzeit solcher Anfahrköpfe 3.4, the starting head 3 is provided with a coupling part 41. A sheet-like seal 43 made of, for example, a thermally resistant fabric essentially covers the entire surface 44 facing the mold cavity 7 of the mold and part of the lateral boundary surfaces 46 of the start-up head 3 that abut against this surface 44. This layered seal 43 also has a sealing function in addition to the sealing function protection for the starting head 3 and thereby extends the service life of such starting heads 3.

Mit einer Prallplatte 16 aus Metall ist eine vorstehende Nase 47 verbunden, die ein, mindestens im Bereich der Dichtkante 49 vorgesehener Dichtungshalter 40 zusammen mit der Dichtung 43 gegenüber dem Anfahrkopf 3 fixiert. Der Dichtungshalter 40 aus spritzgegossenem Kunststoff, wie beispielsweise Polyäthylen, ist kappenförmig über den Anfahrkopf gestülpt. Der Dichtungshalter 40, die Prallplatte 16 und die schichtförmige Dichtung 43 werden in der Regel vor dem Aufsetzen auf den Anfahrkopf gegenseitig aneinander befestigt. Solche vorfabrizierte Dichtungseinheiten können mit einem Handgriff bzw. in wenigen Sekunden auf entsprechende Anfahrköpfe 3 aufgesetzt werden. Der Dichtungshalter 40 kann je nach Material und Formgebung eine gewisse Elastizität aufweisen, so dass die ganze Dichtungseinheit am Anfahrkopf 3 festklemmbar ist. Durch die Elastizität können auch kleine Massdifferenzen verschiedener Anfahrköpfe ausgeglichen werden.A protruding nose 47 is connected to a baffle plate 16 made of metal and fixes a seal holder 40, provided at least in the area of the sealing edge 49, together with the seal 43 relative to the starting head 3. The seal holder 40 made of injection molded plastic, such as polyethylene, is placed in a cap shape over the start-up head. The seal holder 40, the baffle plate 16 and the layered seal 43 are generally attached to one another before being placed on the starting head. Such prefabricated sealing units can be placed on corresponding start-up heads 3 with a handle or in a few seconds. Depending on the material and shape, the seal holder 40 can have a certain elasticity, so that the entire seal unit can be clamped on the starting head 3. Thanks to the elasticity, even small dimensional differences between different start heads can be compensated.

Ein weiterer Vorteil dieses Dichtungshalters 40 ist der gute Schutz der Dichtung 43 und des Anfahrkopfes 3 gegen Wassertropfen aus Sprühdüsen und gegen Feuchtigkeit. Es ist klar, dass der Dichtungshalter 40 aus Kunststoff einen direkten Kontakt zwischen dem metallischen Teil des Anfahrkopfes und dem Formhohlraum 7 der Kokille verhindert und somit den Kokillenverschleiss reduziert.Another advantage of this seal holder 40 is the good protection of the seal 43 and the start-up head 3 against water drops from spray nozzles and against moisture. It is clear that the plastic seal holder 40 prevents direct contact between the metallic part of the start-up head and the mold cavity 7 of the mold and thus reduces mold wear.

Die schichtförmige Dichtung 43 kann aus verschiedenen Materialien bestehen. Ihre Hauptaufgabe besteht darin, den Spalt zwischen dem Anfahrkopf 3 und der gekühlten Kokillenwand während einigen Sekunden nach dem Angiessen, d.h. bis der Stahl oberhalb des Spaltes durch die intensive Kokillenkühlung zur Erstarrung gebracht ist, zu verschliessen.The layered seal 43 can consist of different materials. Their main task is to close the gap between the start-up head 3 and the cooled mold wall during a few seconds after casting, i.e. until the steel has solidified above the gap due to the intensive mold cooling.

Das erfindungsgemässe Dichtungssystem kann bei Knüppel-, Vorblock-, Brammen-, Vorprofil-Kokillen etc. verwendet werden. Der Dichtungshalter bei grossen Kokillen kann anstelle der in den Beispielen dargestellten Block- oder Plattenformen auch nur rahmenförmig sein und im wesentlichen nur der Kontur der Dichtungsfläche folgen. Auch bezüglich der Materialien für den Dichtungshalter und für die Dichtung bestehen im Rahmen der Ansprüche keine Einschränkungen.The sealing system according to the invention can be used in billet, bloom, slab, billet molds, etc. Instead of the block or plate shapes shown in the examples, the seal holder for large molds can also only be frame-shaped and essentially only follow the contour of the sealing surface. There are also no restrictions within the scope of the claims with regard to the materials for the seal holder and for the seal.

Bei Mehrstranganlagen für Stahl kann bei Anwendung des erfindungsgemässen Abdichtverfahrens durch beabsichtigten Giessunterbruch und Wiederanfahren einzelner Stränge die Giessleistung einer störungsbedingten unregelmässigen Stahlanlieferung angepasst werden.In the case of multi-strand systems for steel, when using the sealing method according to the invention, the casting performance can be adapted to an irregular steel delivery caused by a fault by deliberately interrupting the casting and restarting individual strands.

Claims (17)

1. A method for inserting a dummy bar head (3, 33) and sealing the gap between the dummy bar head (3, 33) and a continuous-casting mould (2), especially in casting steel in multi-strand equipment, the dummy bar head (3, 33) being provided with a seal (6, 43) before insertion into the mould (2), characterized in that before the entry of the dummy bar head (3, 33) into the mould (2) a seal retainer (10,20,30,40), which can be destroyed by the inflowing casting metal, is attached to the dummy bar head (3, 33), the dummy bar head (3, 33) is inserted into the mould (2) with a seal (6, 43) arranged between the dummy bar head (3) and the seal retainer (10, 20, 30, 40) and at the start of casting the seal retainer (10, 20, 30, 40) is destroyed by the inflowing casting metal.
2. A method according to claim 1, characterized in that the seal (6, 43) is fastened to the seal retainer before the seal retainer (10, 20, 30, 40) is mounted on the dummy bar head (3, 33).
3. A method according to claim 1 or claim 2, characterized in that the seal retainer (10, 20, 30, 40) and/or the seal (6, 43), on entry into the mould (2) are deformed along their circumferential line conformed to the mould cross section.
4. A method according to any one of claims 1 to 3, characterized in that on insertion of the dummy bar head (3, 33) into the mould (2) the seal retainer (10, 20, 30, 40) is deformed by friction against the mould wall and the seal (6, 43) is thereby pressed against the gap.
5. A method according to any one of claims 1 to 4 for casting with multi-strand equipment, characterized in that during entry of the dummy bar head (3, 33) into the mould (2) for one strand, casting of neighbouring strands is continued without interruption.
6. A method according to any one of claims 1 to 5, characterized in that the seal retainer (10, 20, 30, 40) is destroyed by melting and/or gasification.
7. A method according to any one of claims 1 to 6, characterized in that the coupling members on the dummy bar head (3, 33) are exposed, to create a connection with the cast strand, by the destruction of the seal retainer (10, 20, 30, 40) by the inflowing metal.
8. A sealing apparatus for a continuous casting plant, especially for multi-strand equipment for casting steel, a seal (6, 43) being provided for sealing between a dummy bar head (3, 33) and a mould (2), characterized in that on the end face (9, 34) of the dummy bar head (3, 33) facing the mould cavity (7) of the mould (2) a seal retainer (10, 20, 30, 40) with a fastening area (11, 45) for the seal (6, 43) is provided at least in the region of the sealing edge (49), this seal retainer (10, 20, 30, 40) being able to be destroyed by the inflowing steel, and the seal (6, 43) is arranged between the seal retainer (10, 20, 30, 40) and the dummy bar head (3, 33).
9. A sealing apparatus according to claim 8, characterized in that the seal (6) is cordlike in form.
10. A sealing apparatus according to claim 8, characterized in that the seal (43) is laminar in form.
11. A sealing apparatus according to any one of claims 8 to 10, characterized in that the seal retainer (10,20,30,40) consists of easily deformable material and is greater in its dimensions (21) conformed to the mould cavity cross section (22) for deformation on insertion into the mould than is the mould cavity cross section (22) of the mould.
12. A sealing apparatus according to any one of claims 8 to 11, characterized in that the seal retainer (10, 20, 40) is pyramid-shaped.
13. A sealing apparatus according to any one of claims 8 to 12, characterized in that the seal retainer (10, 20, 30, 40) is provided with a metal baffle plate (16) at the point of impact of the liquid steel.
14. A sealing apparatus according to any one of claims 8 to 13, characterized in that the seal retainer (10, 20) consists of gasifiable expanded plastics, for example expanded polystyrene.
15. A sealing apparatus according to any one of claims 8 to 13, characterized in that the seal retainer (40) consists of an injection-mouldable plastics material.
16. A sealing apparatus according to any one of claims 8 to 15, characterized in that the seal retainer (40) is constructed as a cap which covers the seal (43) and the side of the dummy bar head (3) which faces the mould cavity (7).
17. A sealing apparatus according to any one of claims 8 to 15, characterized in that the seal retainer (40) is constructed as a cap which only covers the seal (43) and the area of the sealing edge (49) of the dummy bar head (3).
EP83112670A 1982-12-20 1983-12-16 Method of and apparatus for sealing a dummy bar head in a continuous-casting mold Expired EP0114309B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH7408/82 1982-12-20
CH7408/82A CH659016A5 (en) 1982-12-20 1982-12-20 METHOD AND DEVICE FOR SEALING A STARTING HEAD IN A CONTINUOUS CASTING COIL.

Publications (2)

Publication Number Publication Date
EP0114309A1 EP0114309A1 (en) 1984-08-01
EP0114309B1 true EP0114309B1 (en) 1987-02-18

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP83112670A Expired EP0114309B1 (en) 1982-12-20 1983-12-16 Method of and apparatus for sealing a dummy bar head in a continuous-casting mold

Country Status (7)

Country Link
EP (1) EP0114309B1 (en)
JP (1) JPS59118252A (en)
CH (1) CH659016A5 (en)
DE (1) DE3369825D1 (en)
ES (1) ES8501655A1 (en)
MX (1) MX168043B (en)
ZA (1) ZA839435B (en)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3603190A1 (en) 1986-02-03 1987-08-06 Schloemann Siemag Ag START-UP HEAD FOR A STEEL TAPE CASTING SYSTEM
CH675975A5 (en) * 1988-03-18 1990-11-30 Concast Standard Ag
JP2513217Y2 (en) * 1990-04-27 1996-10-02 住友重機械工業株式会社 Sealing device between mold and dame barber head
JPH0715655Y2 (en) * 1990-08-13 1995-04-12 新日本製鐵株式会社 Dummy bar for horizontal continuous casting
JPH05285610A (en) * 1992-04-14 1993-11-02 Nippon Steel Corp Mold seal device for starting continuous casting and using method therefor
AT401148B (en) * 1993-03-30 1996-06-25 Voest Alpine Ind Anlagen GASKET FOR A START-UP HEAD FOR USE IN A CONTINUOUS CASTING SYSTEM
AT404105B (en) * 1995-07-27 1998-08-25 Voest Alpine Ind Anlagen METHOD FOR CONTINUOUSLY casting a METAL MELT
ITMI991295A1 (en) * 1999-06-10 2000-12-10 Danieli Off Mecc METHOD FOR SEALING THE LINGOTTERY SET - FALSE BAR IN A CONTINUOUS CASTING SYSTEM AND RELATIVE SEALING ELEMENT
US6273179B1 (en) 1999-06-11 2001-08-14 Ati Properties, Inc. Method and apparatus for metal electrode or ingot casting

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1959104A1 (en) * 1969-11-25 1971-05-27 Demag Ag Oil asbestos paste for stopping of gaps in - mould walls
DE2703148C3 (en) * 1977-01-26 1980-11-06 Nautschno- Proizvodstvennoe Obedinenie Tulatschermet, Tula Start-up line for a continuous casting mold
AT348170B (en) * 1977-03-25 1979-02-12 Voest Ag ACCESS LINE FOR CONTINUOUS CASTING PLANTS
AT352924B (en) * 1978-03-25 1979-10-10 Voest Ag ACCESS LINE FOR CONTINUOUS CASTING PLANTS
AT363208B (en) * 1979-10-08 1981-07-27 Voest Alpine Ag ACCESS STRAND HEAD FOR A CONTINUOUS CASTING SYSTEM

Also Published As

Publication number Publication date
ES528604A0 (en) 1984-12-01
MX168043B (en) 1993-04-29
ES8501655A1 (en) 1984-12-01
ZA839435B (en) 1984-08-29
DE3369825D1 (en) 1987-03-26
EP0114309A1 (en) 1984-08-01
JPS59118252A (en) 1984-07-07
JPH0431779B2 (en) 1992-05-27
CH659016A5 (en) 1986-12-31

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