EP0141904B1 - Continuous casting mould - Google Patents
Continuous casting mould Download PDFInfo
- Publication number
- EP0141904B1 EP0141904B1 EP84108014A EP84108014A EP0141904B1 EP 0141904 B1 EP0141904 B1 EP 0141904B1 EP 84108014 A EP84108014 A EP 84108014A EP 84108014 A EP84108014 A EP 84108014A EP 0141904 B1 EP0141904 B1 EP 0141904B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- mold
- strip
- grids
- continuous casting
- contact surface
- 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.)
- Expired
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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
- B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
- B22D11/055—Cooling the moulds
Definitions
- the invention relates to a continuous casting mold, consisting of an indirect cooling part with a jacket-shaped contact surface between the mold wall and the cast strand and a subsequent direct cooling part with a web-shaped contact surface and coolant openings in the grooves between the webs.
- German Patents 12 83 442 (forming the preamble of claim 1), 18 08 415 and 19 57 314.
- the belt is cooled indirectly in the first part of the mold and in the second part by direct water spraying, in that the strand is guided between longitudinal webs.
- the coolant introduced under pressure is at the belt surface at a speed which is several times the casting speed. led along.
- a vacuum is generated in the molds within the injection zones, which on the one hand prevents the cooling water from backing up to the mold inlet and thus prevents the belt from freezing, and on the other hand causes the lubricant to be sucked in.
- the object of the present invention is to avoid the disadvantages described and to develop a continuous casting mold for the horizontal casting of thin strips of aluminum and aluminum alloys, with which strips can be produced which have no cracks and have a uniform casting structure and thus a smooth surface, so that they can be processed directly by cold rolling without prior mechanical surface treatment.
- this object is achieved by the features of claim 1.
- This web shape increases the size of the directly cooled zone of the cast belts, which leads to more even heat removal. A similar effect can be achieved if the webs are rounded (Fig. 2b).
- a further particular advantage has been shown that the casting speed can be increased by approximately 30% for both unalloyed and alloyed materials without the casting errors mentioned occurring.
- a further improvement of the mold according to the invention can be achieved by coating the surfaces in contact with the surface of the cast strip with a 20 to 40 ⁇ m thick hard chrome layer or a nickel layer.
- the comparative mold A not shown and the mold B according to the invention are of the same design and dimensions with the exception of the webs arranged in the direct cooling part.
- these are flattened in a conventional manner on the contact surface between the mold wall and the cast strand, so that mold A has a contact width of 2.5 mm per web.
- the mold according to the invention is tapered on the contact surfaces, as is shown in perspective in FIG. 1.
- the direct cooling part 3 consists of the coolant openings 4 and the webs 5, which are tapered on the contact surface to the cast strand 6.
- the width of the contact surface in the mold 3 is 0.1 mm.
- the tape from mold A showed sporadic longitudinal cracks (photo 1) and irregular cast structures that appeared on the surface (photo 2).
- the tape from mold B (photo 3) was free of cracks and showed an even casting structure.
- FIG. 2a Two alternative web shapes are shown in FIG. 2.
- the preferred embodiment according to Fig. 2a has pointed web ends, which has a support width of less than 0.1 mm. This bar shape allows casting particularly difficult-to-cast AIMgSi alloys without cracks.
- This web shape is particularly low-wear and therefore suitable for high-strength alloys, especially in connection with hard chrome plating or nickel plating.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
- Manufacture Of Alloys Or Alloy Compounds (AREA)
- Laminated Bodies (AREA)
- Ultra Sonic Daignosis Equipment (AREA)
- Cephalosporin Compounds (AREA)
Abstract
Description
Die Erfindung betrifft eine Stranggießkokille, bestehend aus einem indirekten Kühlteil mit mantelförmiger Berührungsfläche zwischen Kokillenwand und Gußstrang und einem anschließenden direkten Kühlteil mit stegförmiger Berührungsfläche und Kühlmittelöffnungen in den Nuten zwischen den Stegen.The invention relates to a continuous casting mold, consisting of an indirect cooling part with a jacket-shaped contact surface between the mold wall and the cast strand and a subsequent direct cooling part with a web-shaped contact surface and coolant openings in the grooves between the webs.
Kurze Durchlaufkokillen zum horizontalen Gießen dünner Bänder mit indirekter und anschließend direkter Wasserkühlung sind in den deutschen Patentschriften 12 83 442 (den Oberbegriff des Anspruchs 1 bildend), 18 08 415 und 19 57 314 beschrieben. Die Kühlung des Bandes erfolgt dabei im ersten Teil der Kokille indirekt und im zweiten Teil durch direkte Wasseranspritzung, indem der Strang zwischen längs verlaufenden Stegen geführt wird. Das unter Druck eingeführte Kühlmittel wird zwischen den Stegen mit einer das Mehrfache der Gießgeschwindigkeit betragenden Geschwindigkeit an der Bandoberfläche . entlanggeführt. Dabei wird bei den Kokillen innerhalb der Anspritzzonen ein Unterdruck erzeugt, der einerseits einen Rückstau des Kühlwassers zum Kokilleneinlauf hin und damit ein Einfrieren des Bandes verhindert und andererseits eine Ansaugung des Schmiermittels bewirkt.Short continuous molds for the horizontal casting of thin strips with indirect and then direct water cooling are described in German Patents 12 83 442 (forming the preamble of claim 1), 18 08 415 and 19 57 314. The belt is cooled indirectly in the first part of the mold and in the second part by direct water spraying, in that the strand is guided between longitudinal webs. The coolant introduced under pressure is at the belt surface at a speed which is several times the casting speed. led along. A vacuum is generated in the molds within the injection zones, which on the one hand prevents the cooling water from backing up to the mold inlet and thus prevents the belt from freezing, and on the other hand causes the lubricant to be sucked in.
Das Gießen rißfreier Bänder aus hochlegierten Aluminiumwerkstoffen setzt einmal eine extrem genaue, in der Praxis nur schwer realisierbare Einhaltung der Gießparameter, wie Metalltemperatur, Kühlmittelmenge und Schmierstoffdosierung voraus, andererseits sind die erzeugbare Bandbreite sowie die Gießgeschwindigkeit nur begrenzt. Darüber hinaus hat sich gezeigt, daß die Bandoberfläche, vor allem bei hochlegierten Werkstoffen, wie beispielsweise AIMg 5, unregelmäßige Gußstrukturen, wie Seigerungen und Kaltläufe, aufweist, die über die Bandbreite ungleichmäßig ausgebildet sind. Eine Weiterverarbeitung solcher Gußbänder durch Kaltwalzen zu hochwertigem Walzbahd kann nicht ohne vorhergehende mechanische Oberflächenbearbeitung erfolgen. Beim Gießen von 6 bis 15 mm dicken Bändern hat sich vor allem bei Mangan- und/oder Magnesiumhaltigen Werkstoffen gezeigt, daß häufig Längsrisse auftreten.The casting of crack-free strips from high-alloy aluminum materials requires extremely precise compliance with the casting parameters, such as metal temperature, coolant quantity and lubricant dosage, which is difficult to achieve in practice. In addition, it has been shown that the strip surface, especially in the case of high-alloy materials such as
Aufgabe der vorliegenden Erfindung ist es, die beschriebenen Nachteile zu vermeiden und eine Stranggießkokille zum horizontalen Gießen dünner Bänder aus Aluminium und Aluminiumlegierungen zu entwickeln, mit der Bänder herstellbar sind, die keine Risse aufweisen und eine gleichmäßige Gußstruktur und damit glatte Oberfläche haben, so daß sie ohne vorherige mechanische Oberflächenbearbeitung direkt durch Kaltwalzen weiterverarbeitet werden können.The object of the present invention is to avoid the disadvantages described and to develop a continuous casting mold for the horizontal casting of thin strips of aluminum and aluminum alloys, with which strips can be produced which have no cracks and have a uniform casting structure and thus a smooth surface, so that they can be processed directly by cold rolling without prior mechanical surface treatment.
Erfindungsgemäß wird diese Aufgabe durch die Merkmale des Anspruchs 1 gelöst. Durch diese Stegform wird eine Vergrößerung der direkt gekühlten Zone der Gußbänder erzielt, die zu einem gleichmäßigeren Wärmeentzug führt. Ein ähnlicher Effekt läßt sich erzielen, wenn die Stege abgerundet werden (Fig. 2b).According to the invention, this object is achieved by the features of
Den gleichen Effekt kann man nicht durch eine Verringerung der Steganzahl erzielen, da dann die Gefahr eines Rückstaues des Kühlmediums besteht.The same effect cannot be achieved by reducing the number of webs, since there is then a risk of the cooling medium backing up.
Es hat sich gezeigt, daß bei Verwendung der erfindungsgemäßen Kokille die vorher beschriebenen Probleme beim Gießen hochlegierter Aluminiumwerkstoffe weitgehend behoben werden. So lassen sich mit ihr Bänder, beispielsweise aus AIMg 5 oder AIMg 4,5 Mn, auch im Dauerbetrieb rißfrei gießen, wobei betriebsbedingte Schwankungen der Gießtemparameter ohne Einfluß sind.It has been shown that the problems described above when casting high-alloy aluminum materials are largely eliminated when using the mold according to the invention. It can be used to cast tapes, for example from AIMg 5 or AIMg 4.5 Mn, without cracks even in continuous operation, with operational fluctuations in the pouring temperature parameters having no influence.
Die Vergrößerung der direkt gekühlten Fläche führt zudem zu einer einheitlichen Gußstruktur, so daß die sich hierdurch ergebende glatte Bandoberfläche ohne vorhergehende Bearbeitung kalt oder warm gewalzt werden kann.The enlargement of the directly cooled surface also leads to a uniform casting structure, so that the resulting smooth strip surface can be rolled cold or hot without prior processing.
Als weiterer besonderer Vorteil hat sich gezeigt, daß sowohl bei unlegierten als auch bei legierten Werkstoffen die Gießgeschwindigkeit um ca. 30 % gesteigert werden kann, ohne daß es zu den erwähnten Gießfehlern kommt.A further particular advantage has been shown that the casting speed can be increased by approximately 30% for both unalloyed and alloyed materials without the casting errors mentioned occurring.
Eine weitere Verbesserung der erfindungsgemäßen, üblicherweise aus Kupfer gefertigen Kokille kann dadurch erzielt werden, daß die mit der Oberfläche des Gußbandes in Berührung stehenden Flächen mit einer 20 bis 40 j.Lm dikken Hartchromschicht oder einer Nickelschicht überzogen werden.A further improvement of the mold according to the invention, usually made of copper, can be achieved by coating the surfaces in contact with the surface of the cast strip with a 20 to 40 μm thick hard chrome layer or a nickel layer.
Durch diese Maßnahme wird der Kokillenverschleiß verringert und hierdurch die Kokillenstandzeiten, insbesondere beim Gießen hochfester und damit harter Bänder erhöht. Dies ist vor allem in Anbetracht der erfindungsgemäß verringerten Berührungsfläche im direkt gekühlten Kokillenabschnitt von Bedeutung. Darüber hinaus hat sich gezeigt, daß die Neigung zum Kleben des Bandes an der Kokillenlauffläche im indirekt gekühlten Kokillenteil durch eine Hartverchromung oder Vernickelung verringert wird.This measure reduces mold wear and thereby increases mold life, especially when casting high-strength and thus hard strips. This is particularly important in view of the reduced contact area in the directly cooled mold section according to the invention. In addition, it has been shown that the tendency for the tape to stick to the mold tread in the indirectly cooled mold part is reduced by hard chrome plating or nickel plating.
Im folgenden wird die Erfindung an Hand eines Vergleichsbeispieles näher erläutert.The invention is explained in more detail below on the basis of a comparative example.
Die Vergleichskokille A nicht dargestellt und die erfindungsgemäße Kokille B (Fig. 1) sind von gleicher Bauart und Abmessung mit Ausnahme der im direkten Kühlteil angeordneten Stege. Diese sind bei der Kokille A in herkömmlicher Weise an der Berührungsfläche zwischen Kokillenwand und Gußstrang abgeflacht, so daß sich bei der Kokille A eine Berührungsbreite von 2,5 mm je Steg ergibt.The comparative mold A not shown and the mold B according to the invention (FIG. 1) are of the same design and dimensions with the exception of the webs arranged in the direct cooling part. In the case of mold A, these are flattened in a conventional manner on the contact surface between the mold wall and the cast strand, so that mold A has a contact width of 2.5 mm per web.
Demgegenüber ist die erfindungsgemäße Kokille an den Berührungsflächen zugespitzt, wie es in Fig. 1 perspektivisch dargestellt ist. Der direkte Kühlteil 3 besteht aus den Kühlmittelöffnungen 4 und den Stegen 5, die an der Berührungsfläche zum Gußstrang 6 hin zugespitzt sind. Die Breite der Auflagefläche bei der Kokille 3 beträgt 0,1 mm.In contrast, the mold according to the invention is tapered on the contact surfaces, as is shown in perspective in FIG. 1. The
Mit beiden Kokillen wurde ein Band der Dicke 12 mm und der Breite 750 mm bei ansonsten gleichen Gießbedingungen (Metalltemperatur, Gießgeschwindigkeit, Kühlmittelmenge) aus der Legierung AIMg 5 gegossen.With both molds, a band with a thickness of 12 mm and a width of 750 mm was otherwise used same casting conditions (metal temperature, casting speed, amount of coolant) cast from the
Das Band aus der Kokille A zeigte sporadische Längsrisse (Foto 1) und unregelmäßige Gußstrukturen, die sich auf der Oberfläche abzeichnen (Foto 2). Das Band aus der Kokille B (Foto 3) war rißfrei und zeigte eine gleichmäßige Gußstruktur.The tape from mold A showed sporadic longitudinal cracks (photo 1) and irregular cast structures that appeared on the surface (photo 2). The tape from mold B (photo 3) was free of cracks and showed an even casting structure.
In Fig. 2 sind zwei alternative Stegformen dargestellt. Die bevorzugte Ausführungsform nach Fig. 2a weist spitze Stegenden auf, die eine Auflagebreite von weniger als 0,1 mm besitzt. Diese Stegform gestattet es, besonders schwer gießbare AIMgSi-Legierungen rißfrei zu gießen.Two alternative web shapes are shown in FIG. 2. The preferred embodiment according to Fig. 2a has pointed web ends, which has a support width of less than 0.1 mm. This bar shape allows casting particularly difficult-to-cast AIMgSi alloys without cracks.
In Fig. 2b sind abgerundete Stegenden dargestellt, deren Krümmungsradius etwa der Hälfte der Stegbreite entspricht. Diese Stegform ist besonders verschleißarm und daher für hochfeste Legierungen geeignet, insbesondere in Verbindung mit einer Hartverchromung oder Vernickelung.2b shows rounded web ends whose radius of curvature corresponds to approximately half the web width. This web shape is particularly low-wear and therefore suitable for high-strength alloys, especially in connection with hard chrome plating or nickel plating.
Claims (4)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT84108014T ATE32035T1 (en) | 1983-09-19 | 1984-07-09 | CONTINUOUS CASTING MOLD. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE3333811 | 1983-09-19 | ||
DE3333811A DE3333811C1 (en) | 1983-09-19 | 1983-09-19 | Continuous casting mold for aluminum continuous strips |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0141904A1 EP0141904A1 (en) | 1985-05-22 |
EP0141904B1 true EP0141904B1 (en) | 1988-01-20 |
Family
ID=6209489
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP84108014A Expired EP0141904B1 (en) | 1983-09-19 | 1984-07-09 | Continuous casting mould |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0141904B1 (en) |
JP (1) | JPS6087953A (en) |
AT (1) | ATE32035T1 (en) |
CA (1) | CA1245035A (en) |
DE (1) | DE3333811C1 (en) |
NO (1) | NO161606C (en) |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL123039C (en) * | 1958-03-17 | |||
CH528939A (en) * | 1968-11-12 | 1972-10-15 | Vaw Ver Aluminium Werke Ag | Device for the fully continuous casting of metallic strands of thin cross-section, such as strips, wires or the like |
FR2304425A1 (en) * | 1975-03-17 | 1976-10-15 | Alcan Res & Dev | Apparatus for continuous casting of metal strips - by introducing molten metal into moulds space between moving surfaces |
GB2094193B (en) * | 1981-01-28 | 1985-07-17 | Sumitomo Light Metal Ind | Mould for direct-clue casting of metals |
-
1983
- 1983-09-19 DE DE3333811A patent/DE3333811C1/en not_active Expired
-
1984
- 1984-07-09 AT AT84108014T patent/ATE32035T1/en not_active IP Right Cessation
- 1984-07-09 EP EP84108014A patent/EP0141904B1/en not_active Expired
- 1984-07-30 NO NO843062A patent/NO161606C/en unknown
- 1984-09-18 CA CA000463459A patent/CA1245035A/en not_active Expired
- 1984-09-19 JP JP59194951A patent/JPS6087953A/en active Pending
Also Published As
Publication number | Publication date |
---|---|
EP0141904A1 (en) | 1985-05-22 |
NO161606B (en) | 1989-05-29 |
NO843062L (en) | 1985-03-20 |
CA1245035A (en) | 1988-11-22 |
NO161606C (en) | 1989-09-06 |
ATE32035T1 (en) | 1988-02-15 |
JPS6087953A (en) | 1985-05-17 |
DE3333811C1 (en) | 1984-07-26 |
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