EP0873212B1 - Method and device for casting of metal - Google Patents

Method and device for casting of metal Download PDF

Info

Publication number
EP0873212B1
EP0873212B1 EP96938579A EP96938579A EP0873212B1 EP 0873212 B1 EP0873212 B1 EP 0873212B1 EP 96938579 A EP96938579 A EP 96938579A EP 96938579 A EP96938579 A EP 96938579A EP 0873212 B1 EP0873212 B1 EP 0873212B1
Authority
EP
European Patent Office
Prior art keywords
melt
mould
casting
frequency magnetic
thermally insulating
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 - Lifetime
Application number
EP96938579A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0873212A1 (en
Inventor
Jan Erik Eriksson
Magnus HALLEFÄLT
Sten Kollberg
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.)
ABB AB
Original Assignee
ABB AB
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.)
Filing date
Publication date
Application filed by ABB AB filed Critical ABB AB
Publication of EP0873212A1 publication Critical patent/EP0873212A1/en
Application granted granted Critical
Publication of EP0873212B1 publication Critical patent/EP0873212B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • B22D11/10—Supplying or treating molten metal
    • B22D11/11—Treating the molten metal
    • B22D11/114—Treating the molten metal by using agitating or vibrating means
    • B22D11/115—Treating the molten metal by using agitating or vibrating means by using magnetic fields
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/02—Use of electric or magnetic effects

Definitions

  • the present invention relates to a method for continuous or semicontinuous casting of metal or metal alloys in a cooled mould.
  • the invention ensures that the temperature of the metal at the upper surface of the melt, the meniscus, is maintained sufficiently high while the metal is being cast in a mould in which a primary flow of hot metal melt is supplied to a cooled mould, which is open in both ends in the casting direction and this primary flow of melt is braked and split up by means of at least one static or periodic low-frequency magnetic field.
  • the invention also relates to a device for carrying out the invented method.
  • a hot metal melt is supplied to a cooled mould which is open in both ends in the casting direction.
  • the mold is preferably water-cooled.
  • a cast strand is formed while the melt is being cooled by the water-cooled mould.
  • the cast strand leaves the mould, it comprises a solidified, self-supporting surface layer around a remaining residual melt.
  • Melt can be supplied to the mould in a number of ways, by means of one or more tapping jets, by means of a casting tube which opens out below the upper surface of the melt present in the mould, or through channels which open out into the mould.
  • the intention is to brake the inflow of hot melt, partly to avoid an uncontrolled inflow of hot melt containing slag particles or other non-metallic particles, partly to control secondary flows of hot melt arising in the non-solidified portions of the cast strand and hence also the heat distribution in the non-solidified portions of the cast strand as well as the solidification process.
  • An uncontrolled inflow of melt in the non-solidified portions of the cast strand results in problems both from the point of view of quality and production engineering. If inflowing melt is allowed to flow into the mould in an uncontrolled manner, its impulse will cause it to penetrate deep down into the non-solidified portions of the cast strand. This makes difficult the separation of particles contained in the melt.
  • An uncontrolled secondary flow gives rise to problems both from point of view of quality and production engineering in that the solidification process is not controlled. If the upwardly flowing secondary flows of hot melt towards the upper surface, the meniscus, become to weak, there is a risk that the meniscus freezes.
  • a frozen meniscus entails production-engineering problems because the meniscus completely or partially solidifies. Such freezing may be reflected in the quality of the cast strand in the form of surface defects.
  • the surface quality is affected in a negative way by to low a temperature of the melt near the meniscus when a reduced temperature at the meniscus gives a lower rate of melting of casting powder supplied to the upper surface of the melt and hence inferior protection against the melt/cast strand, during its passage through the mould, adhering to the inner walls of the mould.
  • Adherence to the mould results in surface defects and, in the worst case, in tearing off of the solidified self-supporting layer of the cast strand. Such tearing of may lead to the melt breaking through the shell of the strand and running out over the cast strand, downstream of the mould, whereby the casting process has to be stopped and a time-consuming work be initiated of cleaning the casting machine from metal flowing out before it may be restarted. If the upward flows become too strong, formation of waves on the upper surface arises as a result of the turbulence, which pulls down slag from the upper surface into the melt with ensuing quality problems, among other things in the form of unwanted non-metallic particles trapped in the steel.
  • the desired control of the temperature of the melt adjacent the meniscus and the casting conditions in other respect are achieved by the provision, according to the invention, of at least one inductive heater adapted to apply a magnetic alternating field to act on the melt adjacent to the upper surface of the melt, the meniscus.
  • the inductive heater may be of single-phase or polyphase design.
  • the magnetic alternating field which preferably is a high-frequency magnetic alternating field, acts on the melt and develops heat in the melt whereby the temperature of the melt adjacent the meniscus may be controlled simultaneously, or alternatively the high-frequency magnetic alternating field develops compressive forces which act on the melt.
  • compressive forces By means of compressive forces, the pressure between the mould wall and the melt is reduced, thus significantly improving the conditions for lubrication. This gives improved surface quality of the cast strand and a possibility of increasing the casting speed without risking the surface quality. This is achieved primarily by combining these compressive forces, according to the invention, with the braking static or period low-frequency magnetic field.
  • a more controlled temperature distribution is obtained by the provision, according to one embodiment of the invention, of at least one further static or periodic low-frequency magnetic field to act on the non-solidified portions of the cast strand in the mould to control the secondary flows arising.
  • These static or periodic low-frequency magnetic fields are adapted to act in the path of the secondary flows arising in such a way that a controlled temperature distribution is obtained in the non-solidified portions of the cast strand. In this way, both the quality, expressed for example in casting structure and inclusions, and the productivity, expressed as availability and casting speed, are improved because a safe and reliable casting process can be maintained.
  • the same improved control of the temperature distribution is obtained by the provision, according to the invention, of at least one braking static or periodic low-frequency magnetic field which, in addition to the braking of inflowing melt, also stabilizes the surface of the melt, with at least one high-frequency magnetic field which develops compressive forces acting on this stable surface and/or heat in these parts of the melt, in combination with a thermally insulating sleeve, the sleeve being arranged at the inlet end of the mould or directly connected to the inlet end of the mould, so-called hot-top casting.
  • the thermally insulating sleeve is filled at least partially with molten metal.
  • the inductive heater is arranged on a level with the sleeve.
  • the heater applies at least one magnetic alternating field to the molten metal present in the thermally insulated sleeve, to act on the melt adjacent the meniscus of the molten metal present in the thermally insulating sleeve.
  • the high-frequency magnetic alternating field develops compressive forces acting on the melt. These compressive forces reduce the pressure between the wall of the sleeve and the melt, thus significantly improving the conditions for lubrication.
  • This provides significantly improved possibilities of utilizing the advantages offered by hot-top casting for increasing the surface quality of the cast strand, improving and controlling the casting structure of the strand, and increasing the casting speed without risking the casting quality.
  • This is achieved primarily by the combination of at least one static or periodic low-frequency magnetic field which stabilizes the surface of the melt while at the same time the compressive forces developed by the high-frequency magnetic field will act on this stable surface.
  • melt present in the thermally insulating sleeve solidifies and, in particular, it can be avoided that a solidified surface layer is formed and adheres to the wall of the sleeve.
  • melt from solidifying and adhering to the transition from the sleeve to the cooled mould Alternatively, this could have been achieved with an overtemperature of the incoming primary metal flow but this provides conditions in the mould/the sleeve which are both very difficult to control and hazardous, which easily results in catastrophic effects such as surface defects, poor casting structure and running out.
  • the above two embodiments can advantageously be combined to further improve the control of the temperature distribution of the melt during the casting process and, in particular, the temperature distribution in connection with the initial solidification stage adjacent the cooled mould in a continuous or semicontinuous casting process.
  • Figure 1 shows the invention as applied to casting in a conventional mould for continuous or semicontinuous casting
  • Figure 2 shows the invention as applied to a mould which is supplemented with an insulating sleeve which is partly filled with metal during the casting, so-called hot-top casting.
  • a mould 12 which is open in both ends in the casting direction is supplied with a primary flow of hot melt.
  • the mould 12 is usually a water-cooled copper mould. Static or periodic low-frequency magnetic fields are adapted to act on the non-solidified portions 13 of the cast strand 11 and hence brake and split up the melt flowing into the mould 12 and prevent the primary flow of hot melt, which usually contains non-metallic particles, from penetrating deep down into the cast strand 11 and to control the flow in the non-solidified portions 13 of the strand.
  • magnetic poles which may be permanent magnets or, as shown in the figures, induction coils are supplied with direct current or a periodic low-frequency alternating current.
  • the poles comprise a core 14a, 14b, 14c, 14d and windings 15a, 15b, 15c, 15d arranged around the core 14a, 14b, 14c, 14d.
  • a magnetic return path 16a, 16b is arranged adjacent the cores 14a, 14b, 14c, 14d to connect the poles together as an external circuit, such that a return path 16a, 16b and cores 14a, 14b, 14c, 14d together with magnetic fields acting between the poles form a closed magnetic circuit.
  • the first of the applied braking static or periodic low-frequency magnetic fields brakes and splits up the incoming primary flow of hot melt, thus reducing the risk of slag being drawn into the melt while at the same time creating good conditions for separation of non-metallic particles.
  • the splitting up secondary flows arise and a more or less controlled circulation of melt in the non-solidified portions 13 of the cast strand 11.
  • the second static or periodic low-frequency magnetic field controls the secondary flow arising, among other things to ensure a sufficient heat supply to the upper surface 17 of the melt, the meniscus, and to prevent the meniscus 17 from solidifying, it is required that a sufficiently strong flow arises adjacent to the meniscus 17.
  • the static magnetic fields are supplemented with an inductive heater 18 arranged near the mould 12 on a level with the meniscus 17.
  • the inductive heater 18 may be a single-phase or a polyphase heater.
  • the high-frequency magnetic alternating field develops compressive forces acting on the melt 13.
  • the compressive forces reduce the pressure between the wall of the mould 12 and the melt 13 and thus improve the condition for lubrication significantly. If only a high-frequency magnetic field is applied to develop compressive forces acting on the melt, at least during casting of heavy metals or metal alloys such as steel, the pressure reduction is not reliable since the surface 20 of the melt against the mould is not sufficiently stable.
  • the desired improvements from the points of view of quality and production engineering in relation to the prior art for continuous or semicontinuous casting are obtained according to the embodiment of the invention shown in Figure 1 by combining the first braking static field and the high-frequency magnetic field with at least one additional static or periodic low-frequency magnetic field to also control the secondary flow arising and stabilize the surface 20 of the melt such that the compressive forces which are developed by the high-frequency magnetic field will act on a stable surface 20.
  • the combination of the braking static or periodic low-frequency magnetic fields and at least one high-frequency magnetic field thus provides an improved surface quality of the cast strand 11 and a possibility of increasing the casting speed without jeopardizing the surface quality.
  • the mould 12 in the embodiment shown in Figure 2 has, according to an alternative embodiment of the invention, been supplemented by a thermally insulating sleeve 19 at the inlet end of the mould.
  • Thermally insulating sleeves 19 close to cooled moulds are used primarily in semicontinuous casting of weaker blanks such as extrusion blanks of copper or aluminium or alloys based on any of these substances.
  • weaker blanks such as extrusion blanks of copper or aluminium or alloys based on any of these substances.
  • a plurality of blanks of this type are cast on a casting table by conducting the melt, which is tapped from a furnace or an intermediate container, to a plurality of water-cooled moulds disposed in the casting table.
  • An insulating sleeve 19 is then placed over a cooled mould 12 as an extension of the mould 12 in the casting direction. This increases the possibilities of
  • these compressive forces provide improved conditions for lubrication between the melt 13 and the sleeve 19, the melt 13 and the mould 12 and the cast strand 11 and the mould 12 in that the pressure between the melt 13 and the sleeve 19 and between the melt 13 and the mould 12 decreases.
  • the static magnetic field thus stabilizes the surface such that the compressive forces applied by the high-frequency magnetic field act evenly in time and space.
  • the conditions for lubrication are improved while at the same time the formation of a first solidified surface layer is moved by controllable means from the sleeve 19 to the mould 12. This eliminates the risk of a solidified surface layer forming and adhering to the wall of the sleeve 19 and, similarly, melt is prevented from solidifying and adhering to the transition from the sleeve 19 to the cooled mould 12.
EP96938579A 1995-11-06 1996-11-05 Method and device for casting of metal Expired - Lifetime EP0873212B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
SE9503898 1995-11-06
SE9503898A SE9503898D0 (sv) 1995-11-06 1995-11-06 Sätt och anordning vid gjutning av metall
PCT/SE1996/001419 WO1997017151A1 (en) 1995-11-06 1996-11-05 Method and device for casting of metal

Publications (2)

Publication Number Publication Date
EP0873212A1 EP0873212A1 (en) 1998-10-28
EP0873212B1 true EP0873212B1 (en) 2001-08-01

Family

ID=20400083

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96938579A Expired - Lifetime EP0873212B1 (en) 1995-11-06 1996-11-05 Method and device for casting of metal

Country Status (7)

Country Link
EP (1) EP0873212B1 (sv)
JP (1) JPH11514585A (sv)
KR (1) KR100447465B1 (sv)
AT (1) ATE203697T1 (sv)
DE (1) DE69614274T2 (sv)
SE (1) SE9503898D0 (sv)
WO (1) WO1997017151A1 (sv)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111194247A (zh) * 2018-02-26 2020-05-22 日本制铁株式会社 铸模设备

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE515793C2 (sv) * 1997-10-24 2001-10-08 Abb Ab Anordning för kontinuerlig gjutning av metall
SE512692C2 (sv) * 1998-03-02 2000-05-02 Abb Ab Metod och anordning för kontinuerlig gjutning
SE512691C2 (sv) 1998-03-02 2000-05-02 Abb Ab Anordning för gjutning av metall
SE514946C2 (sv) * 1998-12-01 2001-05-21 Abb Ab Förfarande och anordning för kontinuerlig gjutning av metaller
SE516635C2 (sv) * 2000-06-21 2002-02-05 Abb Ab Anordning för stränggjutning av metallmaterial
SE0004082D0 (sv) * 2000-11-08 2000-11-08 Abb Ab Device for casting metal
WO2018218022A1 (en) * 2017-05-24 2018-11-29 Pyrotek, Inc. Electromagnetic modified metal casting process
CN113976843A (zh) * 2021-10-09 2022-01-28 孝义市东义镁业有限公司 一种大规格镁合金圆坯半连续铸造工艺

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TW238268B (sv) * 1992-09-04 1995-01-11 Kawasaki Steel Co

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111194247A (zh) * 2018-02-26 2020-05-22 日本制铁株式会社 铸模设备
CN111194247B (zh) * 2018-02-26 2021-12-10 日本制铁株式会社 铸模设备

Also Published As

Publication number Publication date
DE69614274T2 (de) 2002-05-02
DE69614274D1 (de) 2001-09-06
KR19990067317A (ko) 1999-08-16
WO1997017151A1 (en) 1997-05-15
KR100447465B1 (ko) 2004-10-15
ATE203697T1 (de) 2001-08-15
SE9503898D0 (sv) 1995-11-06
EP0873212A1 (en) 1998-10-28
JPH11514585A (ja) 1999-12-14

Similar Documents

Publication Publication Date Title
US7305271B2 (en) Device and a method for continuous casting
EP0063757B1 (en) Method and apparatus for casting metals and alloys
EP0873212B1 (en) Method and device for casting of metal
CA2305283A1 (en) Continuous casting method, and device therefor
EP0568579B1 (en) A method and a device for casting in a mould
CN113102710A (zh) 一种易切削钢的连铸生产方法
KR19980702446A (ko) 주형내에서의 주조 방법 및 장치
WO1999021670A1 (en) Device for casting of metal
EP0797487B1 (en) Method for casting in a mould
JPS6347537B2 (sv)
JPS63108952A (ja) 連続鋳造における溶湯の電磁かく拌方法
JP2004042068A (ja) 溶融金属の連続鋳造方法及び連続鋳造装置
JP2887625B2 (ja) 連続鋳造装置
KR100314847B1 (ko) 연속주조시 전자기력을 이용한 유동 제어장치
JPH0459156A (ja) 溝型誘導加熱装置およびその操業方法
JPS6333160A (ja) 連続鋳造方法
KR100244660B1 (ko) 연속주조시 주형내 용강유동 제어장치
JPS6153143B2 (sv)
JPH0732098A (ja) 成分が異なる溶鋼の連続鋳造方法
JP3055413B2 (ja) 溶融金属の連続鋳造方法及びその装置
JPH04157053A (ja) 鋼の連続鋳造方法
JPS6333157A (ja) 連続鋳造方法
JPH04224056A (ja) 連続鋳造用溶鋼保持容器
JPH01127158A (ja) 連続鋳造による複合金属材料の製造方法
JPS6333159A (ja) 連続鋳造方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19980522

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT CH DE FR GB IT LI SE

17Q First examination report despatched

Effective date: 19990526

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: ABB AB

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

RIN1 Information on inventor provided before grant (corrected)

Inventor name: KOLLBERG, STEN

Inventor name: HALLEFAELT, MAGNUS

Inventor name: ERIKSSON, JAN, ERIK

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT CH DE FR GB IT LI SE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20010801

Ref country code: CH

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20010801

REF Corresponds to:

Ref document number: 203697

Country of ref document: AT

Date of ref document: 20010815

Kind code of ref document: T

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REF Corresponds to:

Ref document number: 69614274

Country of ref document: DE

Date of ref document: 20010906

EN Fr: translation not filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

EN Fr: translation not filed

Free format text: BO 01/52 PAGES: 283, IL Y A LIEU DE SUPPRIMER: LA MENTION DE LA NON REMISE. LA REMISE EST PUBLIEE DANS LE PRESENT BOPI.

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20121130

Year of fee payment: 17

Ref country code: DE

Payment date: 20121031

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 20121113

Year of fee payment: 17

Ref country code: IT

Payment date: 20121110

Year of fee payment: 17

Ref country code: GB

Payment date: 20121031

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 20121029

Year of fee payment: 17

REG Reference to a national code

Ref country code: SE

Ref legal event code: EUG

REG Reference to a national code

Ref country code: AT

Ref legal event code: MM01

Ref document number: 203697

Country of ref document: AT

Kind code of ref document: T

Effective date: 20131105

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20131105

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20140731

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69614274

Country of ref document: DE

Effective date: 20140603

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20140603

Ref country code: SE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20131106

Ref country code: AT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20131105

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20131105

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20131105

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20131202