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EP0734295A1 - Continuous casting facility and a process for producing thin slabs - Google Patents

Continuous casting facility and a process for producing thin slabs

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Publication number
EP0734295A1
EP0734295A1 EP95906269A EP95906269A EP0734295A1 EP 0734295 A1 EP0734295 A1 EP 0734295A1 EP 95906269 A EP95906269 A EP 95906269A EP 95906269 A EP95906269 A EP 95906269A EP 0734295 A1 EP0734295 A1 EP 0734295A1
Authority
EP
European Patent Office
Prior art keywords
mold
strand
thickness
casting
section
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
EP95906269A
Other languages
German (de)
French (fr)
Other versions
EP0734295B2 (en
EP0734295B1 (en
Inventor
Fritz-Peter Pleschiutschnigg
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.)
SMS Siemag AG
Original Assignee
Mannesmann AG
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/1206—Accessories for subsequent treating or working cast stock in situ for plastic shaping of strands
    • 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
    • B22D11/11—Treating the molten metal
    • B22D11/111—Treating the molten metal by using protecting powders
    • 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
    • B22D11/14—Plants for continuous casting

Definitions

  • the invention relates to a continuous caster and a method for producing thin slabs.
  • the object of the invention is to provide a method and a continuous caster, which make it possible to achieve a predetermined thickness of the thin strand in that optimal conditions for the supply of slag and for reducing the strand thickness are achieved in the mold and in the guide frame during the casting roll.
  • the object is achieved by the features of claims 1 and 4.
  • the subclaims contain advantageous, non-standard further developments of the subclaims.
  • the solution to the problem is independent of the mold type, such as the vertical, vertical bend or circular mold.
  • Fig. 1 Representation of the casting conditions in the mold
  • Fig. 4 Hydraulic behavior of the steel in the mold as a function of the slab thickness based on a 200 mm thick slab x 1,000 mm width
  • the slag height hschlacke 'st mainly on the thickness of Kokilleneintritts ⁇ cross-section and the Strangschaien assume hstrangschale on the lifting height of the mold oszillie ⁇ in power dependent.
  • the constant thickness leads to a constant formation of slag over the width of the casting level and thus to a constant slag supply in the area of the meniscus of the entire continuously forming strand shell (3).
  • This constant formation of slag from casting powder or granulate (5) over the casting width avoids the risk of insufficient lubrication between the immersion nozzle and the copper broadside plates. This danger exists because the casting shell has a glassy structure (silicate structure) with a viscous behavior of approx. 0.5-10 poise.
  • the turbulence caused by the metal flowing into the mold has a considerable influence on the relation (1), which often continues to the bath level and can lead to wave movements, whereby the wave crests can rise above the slag level, which leads to an interruption in the lubrication.
  • This turbulence depends, among other things, on the throughput and the thickness and width of the mold at the cross-section of the dip tube outlet. This is now used as a measure of turbulence hydraulic behavior is defined as the quotient of throughput and thickness and can be represented with the following expression:
  • an electromagnetic brake in the mold area can significantly reduce turbulence in the mold area.
  • ⁇ TA strand cross-section of the solidified slab

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)
  • Paper (AREA)
  • Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
  • Mold Materials And Core Materials (AREA)
  • Moulding By Coating Moulds (AREA)
  • Metal Rolling (AREA)

Abstract

A process and a continuous casting installation for the production of thin slabs, preferably of steel with a predetermined solidification thickness of, e.g., 50 mm, in which an optimum surface quality and internal quality of the strand with minimal and predetermined solidification thickness and plant capacity, and accordingly minimal rolling effort, is achieved by a qualitative adjustment of casting and rolling in the region of the strand guide, oscillation of the casting mold by a hydraulically operated lifting platform, feeding of casting powder to the mold, and an immersion nozzle with a specific cross sectional area of flow relating to the process and continuous casting installation, resulting in a satisfactory supply of casting slag and bath movement in the cast surface compared with a standard slab with a thickness of 200 mm. These conditions from the crater end to the cast surface exert a direct influence on the superficial and internal quality of the strand and on the reliability of the casting process.

Description

Stranggießanlage und Verfahren zur Erzeugung von DünnbrammenContinuous caster and method for producing thin slabs
Die Erfindung betrifft eine Stranggießanlage und ein Verfahren zum Erzeugen von Dünnbrammen.The invention relates to a continuous caster and a method for producing thin slabs.
Aus dem Stand der Technik ist es bekannt, flache Tauchausgüsse zu verwenden, z.B. aus DE 37 09 188 A1. Desweiteren sind hydraulisch angetriebene Hubtische üblich, die es erlauben, Hubhöhe, Frequenz und Form der Oszillation durch Abweichen von der Sinusschwingung selbst während des Gießens zu verändern und optimal zu wählen. Bombierte Kokillen sind beispielsweise der DE 41 31 829 A1 und DE 37 24 628 C1 zu entnehmen. Das Gießwalzen, bei dem während der Erstarrung die Gießdicke so reduziert wird, daß eine verbesserte Innenqualität des Stranges erhalten wird, ist u.a. aus der DE 38 18 077 A1 bekannt.It is known from the prior art to use flat immersion spouts, e.g. from DE 37 09 188 A1. Furthermore, hydraulically driven lifting tables are common, which allow the lifting height, frequency and shape of the oscillation to be changed and optimally selected by deviating from the sinusoidal vibration even during casting. Bombed molds can be found, for example, in DE 41 31 829 A1 and DE 37 24 628 C1. Casting rolling, in which the casting thickness is reduced during solidification in such a way that an improved internal quality of the strand is obtained, is, inter alia, known from DE 38 18 077 A1.
Eine Auswertung des Standes der Technik hat ergeben, daß das Ziel Dünnstränge zu erzeugen, die Lösung komplexer Probleme erfordert und daß die Gesamtheit der beeinflußbaren Variablen über die gesamte Stranggießanlage gesehen so groß ist, daß die Kenntnisse des Durchschnittsfachmannes bei weitem nicht ausreichen und es ihm auch nicht zuzumuten ist, hierfür aus der Vielzahl der möglichen mehr oder weniger brauchbaren Lösungen eine zu finden, die bei gerinstmöglichem Aufwand zu einem zufriedenstellenden Ergebnis führt.An evaluation of the state of the art has shown that the aim of producing thin strands requires the solution of complex problems and that the total of the variables that can be influenced across the entire continuous casting installation is so great that the knowledge of the average specialist is far from sufficient and so is it It is unreasonable to find one of the multitude of possible more or less usable solutions that leads to a satisfactory result with the least possible effort.
Aufgabe der Erfindung ist es, ein Verfahren und eine Stranggießanlage anzugeben, die es möglich machen, eine vorgegebene Dicke des Dünnstranges dadurch zu erreichen, daß optimale Bedingungen bei der Schlackenversorgung sowie bei der Strangdickenreduzierung schon in der Kokille sowie im Führungsgerüst beim Gießwalzen erzielt werden. Die Aufgabe wird gelöst durch die Merkmale der Ansprüche 1 und 4. Vorteilhafte, nicht platt selbstverständliche Weiterbildungen der Nebenansprüche enthalten die Unteran¬ sprüche. Die Lösung der Aufgabe ist unabhängig vom Kokillentyp, wie z.B. der Senkrecht-, Senkrechtabbiege- oder Kreisbogenkokille.The object of the invention is to provide a method and a continuous caster, which make it possible to achieve a predetermined thickness of the thin strand in that optimal conditions for the supply of slag and for reducing the strand thickness are achieved in the mold and in the guide frame during the casting roll. The object is achieved by the features of claims 1 and 4. The subclaims contain advantageous, non-standard further developments of the subclaims. The solution to the problem is independent of the mold type, such as the vertical, vertical bend or circular mold.
Die Figuren dienen zur Veranschaulichung der folgenden beispielhaften Beschreibung der Erfindung.The figures serve to illustrate the following exemplary description of the invention.
Es zeigen:Show it:
Fig. 1 : Darstellung der Gießbedingungen in der KokilleFig. 1: Representation of the casting conditions in the mold
Fig. 2: Technischer Aufwand für gleichbleibende Oberflächenqualität undFig. 2: Technical effort for consistent surface quality and
Gießleistung in Abhängigkeit der Brammendicke bezogen auf eine 200 mm dicke Bramme x 1.000 mm BreiteCasting performance depending on the slab thickness in relation to a 200 mm thick slab x 1,000 mm width
Fig.Fig.
3.1 -3.3: Technischer Aufwand für gleichbleibende Oberflächenqualität und3.1 -3.3: Technical effort for constant surface quality and
Brammendicke in Abhängigkeit von der Gießgeschwindigkeit bezogen auf eine 200 mm dicke Bramme x 1.000 mm BreiteSlab thickness depending on the casting speed based on a 200 mm thick slab x 1,000 mm width
Fig. 4: Hydraulisches Verhalten des Stahles in der Kokille in Abhängigkeit von der Brammendicke bezogen auf eine 200 mm dicke Bramme x 1.000 mm BreiteFig. 4: Hydraulic behavior of the steel in the mold as a function of the slab thickness based on a 200 mm thick slab x 1,000 mm width
Fig. 5: StranggießanlageFig. 5: Continuous caster
Im Rahmen der Erarbeitung der Erfindung durchgeführte Versuche haben ergeben, daß die Oberflächenqualität eines Stranges im wesentlichen von der Schlackenführung abhängt. Hierfür ist der Meniskus, d.h. das Zusammenspiel der Schlackenhöhe (•"•Schlacke) un<:- der aus dem Bad beim Hochschnellen der Kokille heraustretenden Strangschale (hstrangschale) verantwortlich (Fig. 1).Experiments carried out in the course of working out the invention have shown that the surface quality of a strand essentially depends on the slag guidance. This is the meniscus, ie the interaction of the slag height (• "• slag) un <: - responsible for the strand shell (h strand shell) emerging from the bath when the mold is swung up (Fig. 1).
Es hat sich ergeben, daß für eine optimale Schmierung und die Vermeidung von Ober¬ flächenfehlern (unmittelbar unter der Strangoberfläche befindliche Gießpulverteilchen, vorwiegend in Form von Oxiden) das KriteriumIt has been found that the criterion for optimal lubrication and the avoidance of surface defects (casting powder particles located directly below the strand surface, predominantly in the form of oxides) is the criterion
0) "Schlacke ≥ hstrangschale0) "slag ≥ slab shell
erfüllt sein muß.must be fulfilled.
Die Schlackenhöhe hschlacke 'st überwiegend von der Dicke des Kokilleneintritts¬ querschnitts und die Strangschaienhöhe hstrangschale von der Hubhöhe der oszillie¬ renden Kokille abhängig.The slag height hschlacke 'st mainly on the thickness of Kokilleneintritts¬ cross-section and the Strangschaienhöhe hstrangschale on the lifting height of the mold oszillie¬ in power dependent.
Betrachtet man die Größe hschlacke ur|d ihre Abhängigkeit von der Dicke des Kokiiieneintrittsquerschnitts, so zeigt die BeziehungIf you look at the size of the slag ur | d their dependence on the thickness of the die entry cross-section, the relationship shows
.„, , , _,. produzierte Strangoberflache . 2 . • -. . 2 . ",,, _ ,. produced strand surface. 2nd • -. , 2nd
(2) Handicap = — — ~r in m I min x 1 / m ,(2) Handicap = - - ~ r in m I min x 1 / m,
BadoberflächeBathroom surface
die auch als technische Bemühungen, die in das System eingebracht werden muß, bezeichnet werden kann, in unerwarteter Weise folgendes Ergebnis:which can also be called the technical effort that needs to be put into the system, unexpectedly the following result:
Vergleicht man für eine vorgegebene Gießleistung von 2.736 t/min die gebräuchliche 200 mm-Bramme mit einer 50 mm-Bramme und setzt sie in Relation (2) für die 200 mm-Bramme gleich 1 , so steigt dieser Wert für die 50 mm-Bramme auf 16.62, wie aus der Fig. 2 zu entnehmen ist. D.h., die Relation (2) ist umgekehrt proportional zur abnehmenden Strangdicke, wobei die Abhängigkeit einer Exponentialkurve folgt. Dieser Zusammenhang zwischen der Dicke im Gießspiegel (19) und der spezifischen Schlackenproduktion und damit der Schlackenhöhe (4) im Meniskus führt auch zu der Notwendigkeit, daß die aktive Metallbaddicke über die gesamte Gießbeite und damit auch im Bereich des Tauchausgusses konstant zu halten ist.If you compare the usual 200 mm slab with a 50 mm slab for a given casting rate of 2,736 t / min and set it in relation (2) for the 200 mm slab to 1, this value increases for the 50 mm slab to 16.62, as can be seen from FIG. 2. That is, the relation (2) is inversely proportional to the decreasing strand thickness, the dependence following an exponential curve. This relationship between the thickness in the casting level (19) and the specific slag production and thus the slag height (4) in the meniscus also leads to the need for the active metal bath thickness to be kept constant over the entire casting process and thus also in the area of the immersion spout.
Die konstante Dicke führt zu einer konstanten Gießschlackenbildung über die Gießspiegelbreite und damit zu einer konstanten Schlackenversorgung im Bereich des Meniskus der gesamten sich kontinuierlich neu bildenden Strangschale (3). Diese konstante Schlackenbildung aus Gießpulver oder Granulat (5) über die Gießbreite vermeidet die Gefahr einer Mangelschmierung zwischen dem Tauchausguß und den Kupfer-Breitseitenplatten. Diese Gefahr besteht, da die Gießschalcke eine glasige Struktur (Silikat-Struktur) mit einem viskosen Verhalten von ca. 0,5-10 poise aufweist. Durch ihre Zähigkeit kann es zu einer über die Strangbreite gesehen relativen Mangelschmierung im Bereich zwischen Tauchausguß und der Kokillenbreitseite im Vergleich zum restlichen Kokillenbereich im Gießspiegel kommen, wenn der jeweilige Abstand zwischen Tauchausguß und Kokillenbreitseiten kleiner ist als die halbe Strangdicke am Kokillenaustritt.The constant thickness leads to a constant formation of slag over the width of the casting level and thus to a constant slag supply in the area of the meniscus of the entire continuously forming strand shell (3). This constant formation of slag from casting powder or granulate (5) over the casting width avoids the risk of insufficient lubrication between the immersion nozzle and the copper broadside plates. This danger exists because the casting shell has a glassy structure (silicate structure) with a viscous behavior of approx. 0.5-10 poise. Due to their toughness, there can be a relative lack of lubrication in the area between the immersion nozzle and the wide mold side compared to the rest of the mold area in the mold level if the respective distance between the immersion nozzle and the wide mold side is less than half the strand thickness at the mold outlet.
Betrachtet man dagegen wie sich bei einer festgelegten Gießdicke die Relation (2) bei einer Erhöhung der Gießgeschwindigkeit verändert, wie es in Fig. 3 für eine 75/100 und 125 mm-Kokille dargestellt ist, so stellt man fest, daß diese nur linear - mit einer geringen Steigung der Geraden - zunimmt.On the other hand, if you consider how the relation (2) changes when the casting speed increases, as is shown in Fig. 3 for a 75/100 and 125 mm mold, it can be seen that this is only linear - with a slight slope of the straight line - increases.
Von erheblichem Einfluß auf die Relation (1) ist die durch das Einströmen des Metalls in die Kokille entstehende Turbulenz, die sich häufig bis zum Badspiegel fortsetzt und zu Wellenbewegungen führen kann, wobei die Wellenberge sich über den Schlacken¬ spiegel hinaus erheben können, was zu einer Unterbrechung in der Schmierung führt. Diese Turbulenz ist u.a. abhängig vom Durchsatz und der Dicke und Breite der Kokille am Tauchrohraustrittsquerschnitt. Als ein Maß für die Turbulenz wird nunmehr das hydraulische Verhalten als Quotient von Durchsatz und Dicke definiert und kann mit folgendem Ausdruck dargestellt werden:The turbulence caused by the metal flowing into the mold has a considerable influence on the relation (1), which often continues to the bath level and can lead to wave movements, whereby the wave crests can rise above the slag level, which leads to an interruption in the lubrication. This turbulence depends, among other things, on the throughput and the thickness and width of the mold at the cross-section of the dip tube outlet. This is now used as a measure of turbulence hydraulic behavior is defined as the quotient of throughput and thickness and can be represented with the following expression:
. . , ,. , . . . .. Durchsatz in t l min. . ,,. ,. . . .. throughput in t l min
(3) Hydraulisches Verhalten =(3) Hydraulic behavior
Dicke in mmThickness in mm
Werte für das hydraulische Verhalten, bezogen auf die 200 mm dicke Bramme, sind beispielsweise der Fig. 4 zu entnehmen. Es zeigt sich, daß größere Kokillendicken ein deutlich günstigeres hydraulisches Verhalten zur Folge haben.Values for the hydraulic behavior, based on the 200 mm thick slab, can be found, for example, in FIG. 4. It can be seen that larger mold thicknesses result in significantly more favorable hydraulic behavior.
Von Bedeutung bezüglich der Turbulenz ist auch die RelationThe relation is also important with regard to turbulence
(4) ST < 50(4) ST <50
TATA
wobei FJA = Querschnittsfläche des Tauchausgußaustrittswhere FJA = cross-sectional area of the immersion nozzle outlet
FST = Strangquerschnitt der durcherstarrten BrammeFST = strand cross-section of the solidified slab
Außerdem kann eine elektromagnetische Bremse im Kokillenbereich die Turbulenz im Gießspiegelbereich deutlich verringern.In addition, an electromagnetic brake in the mold area can significantly reduce turbulence in the mold area.
Aus den oben aufgestellten und durch Messungen verifizierten Relationen folgt, daß die Verringerung bei der Wahl der Brammendicke am Kokillenaustritt von z.B. 100 mm auf 50 mm und darüber hinaus bei einer Rechteckkokille die Probleme bei der Einhaltung der Relation (1) außerordentlich erhöht. D.h., abgesehen von den Schwierigkeiten bei der Metallzufuhr wird es nahezu unmöglich, auf den geringen Kokilleneintrittsquerschnitt ausreichend Gießpulver aufzubringen, um die entstehende enorm große Strangoberfläche zu schmieren und darüber hinaus die Relation (4) einzustellen. Dagegen läßt sich die Gießgeschwindigkeit bei einer Strangdicke von z.B. 100 mm im Gießspiegel ohne sonderlichen Mehraufwand beträchtlich erhöhen. Das führt zu der überraschenden Lösung, daß es im Bereich des Dünnbrammengießens nicht sinnvoll ist, unbedingt schon am Kokillenaustritt die Brammendicke zu erreichen sondern daß es technisch wesentlich einfacher ist, die Brammendicke, wie sie dem Walzwerk zugeführt wird, darüber hinaus mit Hilfe eines Gießwalzschrittes weiter zu reduzieren und letztlich zu erreichen, wofür sich ein Vielrollengerüst (Segment 0), z.B. ausgebildet als Zangensegment, als vorteilhaft erwiesen hat.From the relationships established above and verified by measurements, it follows that the reduction in the choice of slab thickness at the mold outlet from, for example, 100 mm to 50 mm and, moreover, in the case of a rectangular mold increases the problems in maintaining the relation (1) extremely. That means, apart from the difficulties with the metal supply, it becomes almost impossible to apply sufficient casting powder to the small mold inlet cross-section to lubricate the resulting enormous strand surface and also to set the relation (4). In contrast, the casting speed can be increased considerably with a strand thickness of, for example, 100 mm in the mold level without any particular additional expenditure. This leads to the surprising solution that it does not make sense in the field of thin slab casting To achieve slab thickness but that it is technically much easier to further reduce the slab thickness as it is fed to the rolling mill with the help of a casting-rolling step and ultimately to achieve what a multi-roll stand (segment 0), for example designed as a pliers segment, is used for has proven advantageous.
Aus Fig. 5 ist beispielhaft eine Stranggießanlage zu entnehmen, die sämtliche Erfin¬ dungsmerkmale enthält. 5 shows an example of a continuous casting installation which contains all of the features of the invention.
Bezugszeichenliste 18 optimiertes Gießpulver18 optimized casting powder
19 75 + 2 x 12 mm x 800 - 1.600 mm,19 75 + 2 x 12 mm x 800 - 1,600 mm,
1 QGießpulver Brammenformat im Gießspiegel1 QGießpulver slab format in the mold level
2 Pulver T**, Phasengrenze (Meniskus)2 powders T ** , phase boundary (meniscus)
Pulver/Schlacke 20 20 x 220 mm,Powder / slag 20 20 x 220 mm,
3 "Strangschale- Fließquerschnitt - Tauchausguß3 "strand shell - flow cross section - immersion spout
Höhe Strangschale/Badspiegel 21 hydraulischer KokillenantriebHeight of tub / bath level 21 hydraulic mold drive
4 "Schlacke- 22 FST/FTA ≤ 50*)4 "slag- 22 F ST / FTA ≤ 50 * )
Schlackenhöhe 23 75 + 2 x 0,5 mm oder 75 mm,Slag height 23 75 + 2 x 0.5 mm or 75 mm,
5 hpulven Brammenformat am5 hpulven slab format on
Pulverhöhe KokillenaustrittPowder height mold outlet
6 Tauchausguß 24 Gelenk oder hydraulischer6 immersion nozzle 24 articulated or hydraulic
7 Ablagerung Zylinder oder ähnliches7 deposit cylinder or the like
8 Oxidstrom in die Schlacke 25 Segment 0, z.B. als Zange8 oxide stream into the slag 25 segment 0, e.g. as pliers
9 Vg = Gießgeschwindigkeit ausgebildet9 Vg = casting speed formed
10 QSchlacke = Schlackenverbrauch 26 hydraulischer Zylinder oder10 Q slag = slag consumption 26 hydraulic cylinders or
11 Luft ähnliches11 Air like
12 Kristallisationsgrenze, 27 50 + 2 x 0,5 mm oder 50 mm,12 crystallization limit, 27 50 + 2 x 0.5 mm or 50 mm,
Stahl fest/flüssig Brammendicke nach demSteel solid / liquid slab thickness after the
13 Strangschale Gießwalzvorgang13 Strand shell casting and rolling process
14 Oszillation (Hubhöhe, Frequenz, 28 Segment 1 ... n mit hydraulischer14 oscillation (lifting height, frequency, 28 segment 1 ... n with hydraulic
Form) Anstellung oder ähnlichesForm) employment or the like
15 Kupferplatte 29 vgmax 6 m min 15 copper plate 29 v gmax 6 m min
16 Verteiler 30 50 + 2 x 0,5 mm oder 50 mm,16 distributors 30 50 + 2 x 0.5 mm or 50 mm,
17 Tauchausguß Brammendicke am Ende der17 Dip spout slab thickness at the end of the
Außenmaß z.B. 260 x 60 mm StrangführungExternal dimension e.g. 260 x 60 mm strand guide
Innenmaß z.B. 220 x 20 mmInternal dimensions e.g. 220 x 20 mm
*) FST = Querschnitt des Tauchausgußaustrittes * ) FST = cross-section of the diving spout outlet
^TA = Strangquerschnitt der durcherstarrten Bramme ^ TA = strand cross-section of the solidified slab

Claims

Patentansprüche: Claims:
1. Verfahren zum Erzeugen von Dünnbrammen, das folgende Schritte umfaßt,1. A method for producing thin slabs, comprising the following steps,
- Gießen mittels eines Tauchausgusses in eine bombierte Kokille durch die ein großer Kokilleneintrittsquerschnitt und ein kleiner Kokillenaustrittsquerschnitt erhalten wird, wobei durch den großen Eintrittsquerschnitt die Lebensdauer des Tauchausgusses, gegenüber einem Tauchausguß der dem kleinen Aus¬ trittsquerschnitt angepaßt ist, wesentlich höher ist und desweiteren die Gießpulverzuführung und Schlackenführung wesentlich erleichtert ist,- Pouring by means of an immersion nozzle into a convex mold through which a large mold inlet cross section and a small mold outlet cross section are obtained, the life of the immersion nozzle being considerably greater than that of a diving nozzle which is adapted to the small outlet cross section, and furthermore the casting powder supply, due to the large inlet cross section and slag guidance is considerably easier,
- oszillierende Kokille,- oscillating mold,
- Zuführen des Gießpulvers derart, daß die Bedingung- Feed the mold powder such that the condition
. hSchlacke ≥ hstrangschale, h slag ≥ strand strand
abhängig von der Oszillationshöhe, Form und Frequenz der Kokillenbewegung eingehalten wird,depending on the oscillation height, shape and frequency of the mold movement,
- Reduzieren des Strangquerschnittes unmittelbar unterhalb der Kokille in mehreren Schritten in einem Vielrollengerüst (Segment 0), um parallel zur kontinuierlichen Strangdickenreduzierung im noch flüssigen Stranginneren eine Zwangskonvektion aufzubauen, die der Wirkung des elektromagnetischen Rührens entspricht,- Reduction of the strand cross section immediately below the mold in several steps in a multi-roll stand (segment 0) in order to build up a forced convection in parallel with the continuous strand thickness reduction in the still fluid strand interior, which corresponds to the effect of electromagnetic stirring,
- Erreichen der Enddicke des Stranges am Ende des Vielrollengerüstes (Segment 0),Reaching the final thickness of the strand at the end of the multi-roll stand (segment 0),
- Führen der Erstarrung derart, daß bei Erreichen der Enddicke am Ausgang des Vielrollengerüstes im Stranginneren noch ein 2-Phasengebiet (Kristall/Schmelze) vorliegt.- Conduct the solidification in such a way that when the final thickness at the exit of the multi-roll stand is reached there is still a 2-phase region (crystal / melt).
Einhalten der Bedingung -^ ≤ 50Compliance with the condition - ^ ≤ 50
' TA 'TA
2. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, daß über die gesamte Brammenbreite die aktive Dicke im Gießspiegel, die mit Gießpulver bedeckt und die für die Erschmelzung der Gießschlacke relevant ist, konstant ist.2. The method according to claim 1, characterized in that the active thickness in the mold level, which is covered with mold powder and which is relevant for the melting of the slag, is constant over the entire slab width.
3. Verfahren nach Anspruch 1 und 2, dadurch gekennzeichnet, daß selbst während des Gießens die Frequenz, Hubhöhe und Oszillationsform für die Kokillebewegung frei wählbar sind.3. The method according to claim 1 and 2, characterized in that the frequency, lifting height and oscillation shape for the mold movement are freely selectable even during casting.
4. Verfahren nach Anspruch 1 bis 3, dadurch gekennzeichnet, daß die Kokille so ausgeführt ist, daß der Strang am Kokillenaustritt eine Restbombierung symmetrisch zur Strangmittenachse erhält, die in der Dicke weniger als 4% der Enddicke beträgt.4. The method according to claim 1 to 3, characterized in that the mold is designed so that the strand at the mold exit receives a residual crowning symmetrical to the strand center axis, which is less than 4% of the final thickness in thickness.
5. Stranggießanlage zur Durchführung des Verfahrens nach einem der Ansprüche 1 bis 4, die folgende Elemente enthält,5. Continuous casting installation for carrying out the method according to one of claims 1 to 4, which contains the following elements,
- einen Tauchausguß,- a diving spout,
- eine bombierte oszillierende Kokille, die einen großen Eintrittsquerschnitt und einen kleinen Austrittsquerschnitt aufweist und bei der die Oszillation selbst während des Gießens in Frequenz, Hubhöhe und Form frei wählbar ist,a domed oscillating mold, which has a large inlet cross section and a small outlet cross section and in which the oscillation can be freely selected in frequency, lifting height and shape even during casting,
- eine Gießpulverzuführung, die abhängig von der Oszillationshöhe, -form und frequenz das Gießpulver derart zuführt, daß die Bedingung- A powder feed, which depending on the height, shape and frequency of the powder feed so that the condition
hSchlacke ≥ hstrangschale h slag ≥ strand strand
eingehalten ist,is adhered to
- ein Vielrollengerüst für die kontinuierliche Strangdickenverminderung, wobei der Strang am Vielrollengerüstausgang seine Enddicke bei noch flüssigem Kern auf¬ weist, einen Tauchausguß und Erstarrungsquerschnitt, die so ausgelegt sind, daß die Bedingunga multi-roll stand for continuous strand thickness reduction, the strand at the end of the multi-roll stand having its final thickness with the core still liquid, a diving spout and solidification cross section, which are designed so that the condition
ST < 50ST <50
TATA
erfüllt ist.is satisfied.
6. Stranggießanlage nach Anspruch 5, dadurch gekennzeichnet, daß über die gesamte Brammenbreite die Dicke im Gießspiegel, die mit Gießpulver bedeckt ist, einschließlich des Bereiches zwischen den Tauchausgußwänden und den jeweiligen Kokillenbreitseitenplatten max. 120% der entsprechenden Strangdicke am Kokillenaustritt beträgt.6. Continuous caster according to claim 5, characterized in that over the entire slab width, the thickness in the mold level, which is covered with mold powder, including the area between the immersion pouring walls and the respective mold wide side plates max. 120% of the corresponding strand thickness at the mold exit is.
7. Stranggießanlage nach Anspruch 5 und 6, dadurch gekennzeichnet, daß die Rollen im Vielrollengerüst so angeordnet sind, daß durch die Strangdickenreduzierung im noch flüssigen Stranginneren eine Rührwirkung erzielt wird und gleichzeitig das Entstehen von Innenrissen verhindert wird.7. Continuous casting plant according to claim 5 and 6, characterized in that the rollers are arranged in the multi-roll stand so that a stirring effect is achieved by the strand thickness reduction in the still liquid strand interior and at the same time the occurrence of internal cracks is prevented.
8. Stranggießanlage nach Anspruch 5 bis 7, dadurch gekennzeichnet, daß die Bombierung der Kokille so ausgeführt ist, daß die Restbombierung am Kokillenaustritt höchstens 4% der Strangdicke beträgt. 8. Continuous caster according to claim 5 to 7, characterized in that the crowning of the mold is carried out so that the remaining crowning at the mold outlet is at most 4% of the strand thickness.
EP95906269A 1994-01-28 1995-01-20 Process for producing thin slabs Expired - Lifetime EP0734295B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE4403049 1994-01-28
DE4403049A DE4403049C1 (en) 1994-01-28 1994-01-28 Continuous caster and method for producing thin slabs
PCT/DE1995/000095 WO1995020445A1 (en) 1994-01-28 1995-01-20 Continuous casting facility and a process for producing thin slabs

Publications (3)

Publication Number Publication Date
EP0734295A1 true EP0734295A1 (en) 1996-10-02
EP0734295B1 EP0734295B1 (en) 1998-04-01
EP0734295B2 EP0734295B2 (en) 2002-05-02

Family

ID=6509215

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Application Number Title Priority Date Filing Date
EP95906269A Expired - Lifetime EP0734295B2 (en) 1994-01-28 1995-01-20 Process for producing thin slabs

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US (1) US6568461B1 (en)
EP (1) EP0734295B2 (en)
JP (1) JP3085978B2 (en)
CN (1) CN1046449C (en)
AT (1) ATE164540T1 (en)
AU (1) AU1453595A (en)
BR (1) BR9506653A (en)
CA (1) CA2181908A1 (en)
DE (2) DE4403049C1 (en)
DK (1) DK0734295T4 (en)
ES (1) ES2114304T5 (en)
RU (1) RU2134178C1 (en)
WO (1) WO1995020445A1 (en)
ZA (1) ZA95671B (en)

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Publication number Priority date Publication date Assignee Title
EP0832704A1 (en) 1996-09-19 1998-04-01 Hoogovens Staal B.V. Continuous casting machine
DE19639302C2 (en) * 1996-09-25 2000-02-24 Schloemann Siemag Ag Method and device for producing thin slabs on a continuous caster
DE19639297C2 (en) * 1996-09-25 2000-02-03 Schloemann Siemag Ag Method and device for high-speed continuous casting plants with a reduction in strand thickness during solidification
DE19710791C2 (en) * 1997-03-17 2000-01-20 Schloemann Siemag Ag Optimized forms of the continuous casting mold and the immersion nozzle for casting steel slabs
EP0917922B1 (en) * 1997-11-21 2003-06-25 SMS Demag AG Process and plant for continuous casting slabs
DE19801822C1 (en) * 1998-01-15 1999-03-18 Mannesmann Ag Continuous casting of metals
NL1014024C2 (en) * 2000-01-06 2001-07-09 Corus Technology Bv Apparatus and method for continuous or semi-continuous casting of aluminum.
US20080179036A1 (en) * 2007-01-26 2008-07-31 Nucor Corporation Continuous steel slab caster and methods using same
US8020605B2 (en) * 2007-01-26 2011-09-20 Nucor Corporation Continuous steel slab caster and methods using same
ITMI20120046A1 (en) * 2012-01-18 2013-07-19 Arvedi Steel Engineering S P A PLANT AND PROCEDURE FOR THE CONTINUOUS QUICK CASTING OF STEEL BRAMME AND STEEL BRAMME
WO2018051483A1 (en) * 2016-09-16 2018-03-22 日新製鋼株式会社 Continuous casting method
CN110576163B (en) * 2019-09-28 2021-07-20 江苏联峰能源装备有限公司 Method for producing high-carbon manganese-chromium steel by large-section continuous casting round billet

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Also Published As

Publication number Publication date
DK0734295T4 (en) 2002-06-17
JP3085978B2 (en) 2000-09-11
ES2114304T5 (en) 2002-11-16
ZA95671B (en) 1995-09-28
AU1453595A (en) 1995-08-15
JPH09508070A (en) 1997-08-19
ATE164540T1 (en) 1998-04-15
DK0734295T3 (en) 1998-10-19
WO1995020445A1 (en) 1995-08-03
BR9506653A (en) 1997-09-16
CA2181908A1 (en) 1995-08-03
ES2114304T3 (en) 1998-05-16
RU2134178C1 (en) 1999-08-10
DE4403049C1 (en) 1995-09-07
CN1139892A (en) 1997-01-08
US6568461B1 (en) 2003-05-27
CN1046449C (en) 1999-11-17
EP0734295B2 (en) 2002-05-02
DE59501780D1 (en) 1998-05-07
EP0734295B1 (en) 1998-04-01

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