EP0241387B1 - Giessform, die die Regulierung der Höhe der freien Oberfläche von Metallschmelzen zur Berührung mit der Giessform beim vertikalen Giessen gestattet - Google Patents

Giessform, die die Regulierung der Höhe der freien Oberfläche von Metallschmelzen zur Berührung mit der Giessform beim vertikalen Giessen gestattet Download PDF

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Publication number
EP0241387B1
EP0241387B1 EP87420070A EP87420070A EP0241387B1 EP 0241387 B1 EP0241387 B1 EP 0241387B1 EP 87420070 A EP87420070 A EP 87420070A EP 87420070 A EP87420070 A EP 87420070A EP 0241387 B1 EP0241387 B1 EP 0241387B1
Authority
EP
European Patent Office
Prior art keywords
mould
metal
film
mould according
casting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP87420070A
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English (en)
French (fr)
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EP0241387A1 (de
Inventor
Jean-Pierre Riquet
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.)
Cegedur Societe de Transformation de lAluminium Pechiney SA
Original Assignee
Cegedur Societe de Transformation de lAluminium Pechiney SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Cegedur Societe de Transformation de lAluminium Pechiney SA filed Critical Cegedur Societe de Transformation de lAluminium Pechiney SA
Priority to AT87420070T priority Critical patent/ATE39332T1/de
Publication of EP0241387A1 publication Critical patent/EP0241387A1/de
Application granted granted Critical
Publication of EP0241387B1 publication Critical patent/EP0241387B1/de
Expired legal-status Critical Current

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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
    • B22D11/10—Supplying or treating molten metal
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
    • B22D11/059—Mould materials or platings

Definitions

  • the invention relates to an ingot mold for adjusting the level at which it is in contact with the free surface of the metal in a vertical casting.
  • French patent 1,398,526 teaches the use of a strip of fiberfrax bonded to the ingot mold so as to reduce the height of metal in contact with the ingot mold, and therefore to reduce the effects due to indirect cooling.
  • this reduction in height cannot be fixed once and for all, since it depends in particular on the speed of casting.
  • this parameter varies, it is necessary either to change the mold, or at least to modify the height of the strip. What confers a lack of flexibility to a solution bringing in the end only a partial suppression of heterogeneities.
  • HAT TOP loaded casting with enhancement
  • French patent 2,417,357 has claimed a process in which the axial length of the part of the ingot mold in contact with the molten metal is varied by putting into action a sleeve which slides on the inner wall of the ingot mold.
  • Such a system has the disadvantage during untimely solidification of the metal that it leads to adhesion between the ingot mold and the cuff, thus causing the parts present to be torn off when the sliding movement is carried out.
  • This means consists in applying to the liquid in the course of solidification a periodic magnetic field of variable intensity and direction substantially parallel to the axis of the ingot mold and of adapting its intensity as a function of the desired level.
  • the advantage of such a method is therefore to allow the metal-ingot contact height and consequently the thickness of the cortical layer to be reduced at will simply with a coil supplied by a current of industrial frequency 50 or 60 Hz knowing that any electrical failure will only have the effect of varying the height of metal in the ingot mold, that is to say that any risk of leakage of liquid metal will be eliminated, which is not the case in casting electromagnetic.
  • the presence of an ingot mold while limiting the possibility of oxidation of the liquid metal at the meniscus, prevents, by the contact it has with the metal, any displacement of the oxide film towards the side wall. and therefore any risk of tingling on the surface of the semi-finished product.
  • the field applied to the metal also has the effect of creating forces inside the liquid which homogenize the cooling and tend to cause a refinement of the pouring grain.
  • the solution consisting in surrounding the ingot mold by an annular coil if it has the great advantage of not modifying in any way the conventional assembly of the casting looms, it has on the other hand the disadvantage of entailing a significant consumption of energy electric.
  • the ingot mold absorbs part of the magnetic field representing approximately 15 to 30% of the total energy consumed.
  • the coil must be away from the liquid metal; however, as the intensity of the magnetic field decreases all the more as this distance is great, this results in an additional loss of energy.
  • an ingot mold characterized in that it consists at least in its lower part by a metal, that it is coated internally with a film of electrically insulating material, that it has, along at least one generator, over its entire height and over its entire thickness, an insert made of electrically insulating material, which it is provided externally at said lower part with two terminals placed on either side of said insert and connected to an alternating current source.
  • the ingot mold is constructed of metal and preferably a metal having a low electrical resistivity such as copper or aluminum and their alloys. This poses no problem since the ingot molds are traditionally made of such metals.
  • the mold it is not necessary for the mold to be entirely made of metal and it is even preferable to use composite molds in which the use of such a material is limited to the lower part and the upper part is provided with the flange with a material that is otherwise insulating, at least a poor conductor of electricity such as stainless steel, for example. Indeed, we will see later that by limiting the passage height of the current in the mold, we get better results.
  • the ingot mold according to the invention is characterized in particular in that it is coated internally with a film of electrically insulating material in order to avoid the passage of current from the ingot mold to the cast metal.
  • This film must completely cover the internal surface of the mold from the bottom up. It is desirable that this film is not a good thermal insulator because it would disturb the heat exchanges between mold and metal and would have unfortunate repercussions on the quality of the products obtained. This is why the applicant has been led to study this problem closely and has found after numerous tests that only certain films are applicable.
  • the ingot mold is made of aluminum or one of its alloys of an aluminum oxide film obtained by anodization.
  • this film whatever the type of anodization used, forms a continuous coating, relatively resistant to the passage of current, and good conductor of heat since thicknesses as small as 1 ⁇ .Lm allow the application of voltages close to 100 volts.
  • this type of coating is very resistant to abrasion, and can be impregnated with a lubricating agent (hot grease) to facilitate casting.
  • this oxide easily lends itself to coloring, which makes it possible to detect any deterioration of the coating being produced.
  • enamel film Another type of coating having the same advantages as oxide is the enamel film, the production of which makes use of techniques known to those skilled in the art.
  • Another interesting solution consists in separating the film from the cast metal with a layer of graphite a few millimeters thick, which also avoids the need for a lubricating agent.
  • the invention is also characterized in that the ingot mold has, according to at least one generator, over its entire height and over its entire thickness, an insert made of electrically insulating material. It is indeed necessary for the mold to perform a function similar to that of the coil, that it allows the current flowing through it to flow in a direction perpendicular to the axis of the mold. This is obtained by slitting the mold over its entire height, by inserting into this slot an electrical insulator and by supplying the mold with alternating current from two terminals placed on its outer wall on either side of said insert, and at the level of the metallic lower part.
  • This insulator can be any material known to those skilled in the art, such as mica for example, including the materials constituting the film and in particular in the case of an aluminum ingot mold or one of its alloys, oxide obtained by anodization; the two terminals for connection to the electrical network are of any known type.
  • FIG. 1 there is a supply nozzle (1) made of liquid metal, a stopper rod (2) for level regulation, an ingot mold (3) cooled directly by a fluid (4) which then cools the metal (5) directly at point (6).
  • the right half ingot mold is equipped with a coil (7) which is supplied with an alternating voltage (8) in order to create the magnetic field of direction (9) and to cause the lowering of the level of the contact line of the surface of the metal with the ingot mold of a point (10) in the casting of the prior art at point (11) according to the method, point which is located at the intersection (12) of the solidification front (13 ) resulting from indirect cooling and the front (14) resulting from direct cooling.
  • the contact height of the metal with the ingot mold has been reduced from a height h 1 to an extremely small height h 2 which can be assimilated to point (11).
  • an aluminum ingot mold (15) is seen internally coated with an oxide film (16) obtained by anodization having on one of its generators a slot (17) whose facing faces have also been anodized and two terminals (18) which are connected to a non-alternating current source represented.
  • a composite ingot mold is seen formed from an upper part (19) of stainless steel and a lower part (20) of aluminum.
  • the assembly is internally coated with a film (21) of fluorocarbon resin.
  • two terminals (22) connected to an alternating current source not shown.
  • the invention can be illustrated by means of the following application examples which compare, for 3 types of ingot molds, the intensity necessary to lower the level of the line of contact of the metal with the ingot mold respectively by 15, 30 and 40 mm in an aluminum ingot mold of section 1100 x 300 mm and in which the metal level in the center was fixed at 60 mm from the base of the ingot mold.
  • Type 1 although less efficient, nevertheless constitutes very significant progress compared to the ingot molds of the prior art since the intensity is practically divided by 2.
  • the present invention finds its application in the casting of metallurgical semi-products, in particular aluminum and its alloys such as, for example, lithium alloys and in which it is desired to obtain both a cortical zone of practically zero thickness, a grain end without prior addition of refining agents such as AT58 and an absence of pins.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Mold Materials And Core Materials (AREA)
  • Dental Prosthetics (AREA)
  • Moulds For Moulding Plastics Or The Like (AREA)
  • Soil Working Implements (AREA)
  • Casting Devices For Molds (AREA)
  • Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
  • Moulds, Cores, Or Mandrels (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)

Claims (11)

1. Gießform (15), die die Regulierung der Höhe, auf der sie im Kontakt mit der freien Oberfläche des Metalls bei einem Vertikalguß ist, gestattet, dadurch gekennzeichnet, daß sie wenigstens in ihrem unteren Teil aus einem Metall besteht, daß sie innen mit einer Schicht (16) aus elektrisch isolierendem Material überzogen ist, daß sie längs wenigstens einer Mantellinie auf ihrer ganzen Höhe und ihrer ganzen Wanddicke einen Einsatz (17) aus elektrisch isolierendem Material aufweist, und daß sie äußerlich auf Höhe des unteren Teils mit zwei Anschlußklemmen (18) versehen ist, die zu beiden Seiten des Einsatzes angeordnet und mit einer Wechselstromquelle verbunden sind.
2. Gießform nach dem Anspruch 1, dadurch gekennzeichnet, daß das Metall, das sie bildet, einen niedrigen elektrischen Widerstand hat.
3. Gießform nach dem Anspruch 1, dadurch gekennzeichnet, daß sie einen oberen Teil (19) aufweist, der aus einem isolierenden oder mittelmäßig elektrisch leitenden Material besteht.
4. Gießform nach dem Anspruch 1, dadurch gekennzeichnet, daß das Metall, das sie bildet, zu der von Kupfer, Aluminium und deren Legierungen gebildeten Gruppe gehört.
5. Gießform nach dem Anspruch 4, dadurch gekennzeichnet, daß, wenn das Metall Aluminium und seine Legierungen ist, der innere Überzug eine durch anodische Oxidation erhaltene Aluminiumoxidschicht ist.
6. Gießform nach dem Anspruch 5, dadurch gekennzeichnet, daß die Schicht gefärbt ist.
7. Gießform nach dem Anspruch 1, dadurch gekennzeichnet, daß der innere Überzug eine Emailschicht ist.
8. Gießform nach dem Anspruch 1, dadurch gekennzeichnet, daß der innere Überzug eine Fluorkohlenstoffharzschicht ist.
9. Gießform nach dem Anspruch 1, dadurch gekennzeichnet, daß der innere Überzug mit einem Schmiermittel bedeckt ist.
10. Gießform nach dem Anspruch 1, dadurch gekennzeichnet, daß die Schicht vom gegossenen Metall durch eine Graphitschicht getrennt ist.
11. Gießform nach dem Anspruch 1, dadurch gekennzeichnet, daß der Einsatz aus einem Material gleicher Zusammensetzung wie der der Schicht ist.
EP87420070A 1986-03-13 1987-03-11 Giessform, die die Regulierung der Höhe der freien Oberfläche von Metallschmelzen zur Berührung mit der Giessform beim vertikalen Giessen gestattet Expired EP0241387B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT87420070T ATE39332T1 (de) 1986-03-13 1987-03-11 Giessform, die die regulierung der hoehe der freien oberflaeche von metallschmelzen zur beruehrung mit der giessform beim vertikalen giessen gestattet.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8604117A FR2595596B1 (fr) 1986-03-13 1986-03-13 Lingotiere permettant de regler le niveau suivant lequel elle est en contact avec la surface libre du metal dans une coulee verticale
FR8604117 1986-03-13

Publications (2)

Publication Number Publication Date
EP0241387A1 EP0241387A1 (de) 1987-10-14
EP0241387B1 true EP0241387B1 (de) 1988-12-21

Family

ID=9333414

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87420070A Expired EP0241387B1 (de) 1986-03-13 1987-03-11 Giessform, die die Regulierung der Höhe der freien Oberfläche von Metallschmelzen zur Berührung mit der Giessform beim vertikalen Giessen gestattet

Country Status (12)

Country Link
US (1) US4735255A (de)
EP (1) EP0241387B1 (de)
JP (1) JPS62227553A (de)
KR (1) KR870008644A (de)
CN (1) CN87101863A (de)
AT (1) ATE39332T1 (de)
AU (1) AU579567B2 (de)
DE (1) DE3760022D1 (de)
ES (1) ES2005055B3 (de)
FR (1) FR2595596B1 (de)
GR (1) GR3000001T3 (de)
NZ (1) NZ219581A (de)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2595597B1 (fr) * 1986-03-13 1988-04-29 Cegedur Dispositif de reglage du niveau de la ligne de contact de la surface libre du metal avec la lingotiere dans une coulee verticale
FR2609656B1 (fr) * 1987-01-15 1989-03-24 Cegedur Procede de reglage au niveau de la ligne de contact de la surface libre du metal avec la lingotiere dans une coulee verticale de produits de section quelconque
EP0464151A4 (en) * 1989-03-20 1992-07-01 Olin Corporation In-mold electromagnetic stirring of molten metal during casting
DE4402500C2 (de) * 1994-01-28 1995-12-21 Aeg Elotherm Gmbh Gießkokille
CN105671437A (zh) * 2016-01-25 2016-06-15 陈焕道 一种发动机节气门的制备方法

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB752271A (en) * 1954-05-17 1956-07-11 Rossi Irving Improvements in moulds for use in the continuous casting of metals and particularly steel
US3467166A (en) * 1967-03-01 1969-09-16 Getselev Zinovy N Method of continuous and semicontinuous casting of metals and a plant for same
SE346234B (de) * 1970-03-03 1972-07-03 Asea Ab
AT303280B (de) * 1970-09-22 1972-11-27 Plansee Metallwerk Kokille für das Stranggießen von Metallen
US3702155A (en) * 1970-12-09 1972-11-07 Kuibyshevsky Metallurigchesky Apparatus for shaping ingots during continuous and semi-continuous casting of metals
JPS59133912A (ja) * 1983-01-17 1984-08-01 ウクラインスキイ・ナウチノ−イスレドヴアテルスキイ・インスチテユ−ト・メタルロフ 縦方向に変化する横断面形状を有する物品を作るための圧延成形機械
JPS59153550A (ja) * 1983-02-23 1984-09-01 Kawasaki Steel Corp 連続鋳造用モ−ルド

Also Published As

Publication number Publication date
FR2595596B1 (fr) 1988-04-29
KR870008644A (ko) 1987-10-19
CN87101863A (zh) 1987-09-23
JPS62227553A (ja) 1987-10-06
US4735255A (en) 1988-04-05
EP0241387A1 (de) 1987-10-14
AU6995487A (en) 1987-09-17
GR3000001T3 (en) 1989-09-29
ES2005055B3 (es) 1990-11-16
AU579567B2 (en) 1988-11-24
FR2595596A1 (fr) 1987-09-18
NZ219581A (en) 1988-04-29
DE3760022D1 (en) 1989-01-26
ATE39332T1 (de) 1989-01-15
JPH0137224B2 (de) 1989-08-04

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