EP1844880A1 - Bandgiessen - Google Patents

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Publication number
EP1844880A1
EP1844880A1 EP06450056A EP06450056A EP1844880A1 EP 1844880 A1 EP1844880 A1 EP 1844880A1 EP 06450056 A EP06450056 A EP 06450056A EP 06450056 A EP06450056 A EP 06450056A EP 1844880 A1 EP1844880 A1 EP 1844880A1
Authority
EP
European Patent Office
Prior art keywords
coolant
cooling
strip
casting
process according
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.)
Withdrawn
Application number
EP06450056A
Other languages
English (en)
French (fr)
Inventor
Hubert Sommerhofer
Peter Sommerhofer
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.)
SO and SO Sommerhofer OEG
Original Assignee
SO and SO Sommerhofer OEG
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 SO and SO Sommerhofer OEG filed Critical SO and SO Sommerhofer OEG
Priority to EP06450056A priority Critical patent/EP1844880A1/de
Priority to BRPI0711537-7A priority patent/BRPI0711537A2/pt
Priority to CA002647894A priority patent/CA2647894A1/en
Priority to PCT/EP2007/003210 priority patent/WO2007115827A1/en
Priority to CNA2007800131190A priority patent/CN101484257A/zh
Priority to EP07724151A priority patent/EP2010345A1/de
Priority to JP2009504636A priority patent/JP2009533225A/ja
Priority to US12/226,261 priority patent/US20090314460A1/en
Publication of EP1844880A1 publication Critical patent/EP1844880A1/de
Priority to NO20084271A priority patent/NO20084271L/no
Withdrawn legal-status Critical Current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
    • B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
    • B22D11/0637—Accessories therefor
    • B22D11/068—Accessories therefor for cooling the cast product during its passage through the mould surfaces
    • B22D11/0682—Accessories therefor for cooling the cast product during its passage through the mould surfaces by cooling the casting wheel
    • 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
    • B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
    • B22D11/0602—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars formed by a casting wheel and belt, e.g. Properzi-process
    • 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
    • B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
    • B22D11/0622—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars formed by two casting wheels
    • 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
    • B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
    • B22D11/0637—Accessories therefor
    • B22D11/068—Accessories therefor for cooling the cast product during its passage through the mould surfaces
    • B22D11/0685—Accessories therefor for cooling the cast product during its passage through the mould surfaces by cooling the casting belts

Definitions

  • the invention concerns the strip casting of metals of all kinds with indirectly cooling the strip and a device for such a cooling method according to the introducing part of claim 1.
  • strip casting method exists in various forms, either with two or with one belt, in more recent cases with no belt at all, but with two rotating drums which form a gap between their mantle surfaces, and more exotic forms with one drum and a belt or a drum alone. All these variants have a so called travelling mould and are summoned in the description and the claims with the term "strip casting" and the invention covers all of them.
  • cast metal is fed by a special feeding device into this gap and solidifies in the area of this gap, at least on its surface, sufficient to bring the formed metal strip (or sheet) in manageable state. Cooling occurs only indirectly, this means that water is sprayed on the rear side of the belt(s) or the inner mantle surface of the drums and not on the strip directly. Beside these process variants exists the possibility to cast on one wheel with a cavity in it and one belt closing this cavity (Rotary machine) where the wheel is cooled inside by a water spray and the belt on its outer side also by water spray. In case of the single roll caster the casting melt is given on top of a single wheel without a cavity, the wheel is cooled inside, so the cooling starts only from one side of the strip. Beside the twin roll caster, this process may also be promising for the future.
  • strip casting as a continuous casting process is a very effective way of producing semi-finished or nearly finished products.
  • Products are sheets or strips, thin strips, wires and rods.
  • Cast materials are ferrous metals like steel as well as nonferrous metals like copper, aluminium, magnesium, nickel and so on as well as their alloys.
  • Water as coolant has some very important disadvantages like low operation temperature as a consequence of low evaporation temperature and there is also the danger of explosions when water gets in contact with hot casting metal directly.
  • the strong cooling to low temperatures causes high temperature gradients in the travelling moulds reducing the life time of them as a consequence of crack formation after a short operation times.
  • the invention proposes the use of liquid metal or ionic liquids as cooling medium, preferably in a turbulent flow. This ensures that the cooling properties and characteristics are well defined and controllable.
  • Ionic liquids or designer liquids is the name for a group of salts composed of organic cations and mostly inorganic anions which generally have a melting point below 100°C. They may be used with the invention as long they do not decompose at the maximal working temperature of the process or react with the casting device under the given circumstances. In the following description, they are in most cases not mentioned expressively, but always included when the term "liquid metal” or "coolant” is used.
  • the first is referred to as “cast metal” and the second as “liquid metal”, a somewhat artificial but practical distinction.
  • the indirect cooling uses, according to the invention, a liquid metal like lead, tin, bismuth, gallium, indium or alloys of them as well as other liquid metals or alloys being liquid below the solidification temperature of the cast metal or alloy.
  • the feature of indirect cooling in strip casting with liquid metal ensures a very constant and easy controllable cooling behaviour.
  • the cooling intensity can be adjusted by changing the coolant flow rate and coolant feed temperature. This allows to realize higher temperatures on the cooling side of the mould leading to lower temperature gradients in the mould (longer life time, because lower stress induces less cracks of the mould on the side of the cast metal).
  • the formation of an air gap between strip and travelling moulds can be prevented in the rotary type and single wheel process.
  • the coolant has, in Centigrade Celsius, a melting point which is lower or equal 60 % of the melting point of the casting material in Centigrade Celsius.
  • the direction of the flow of the coolant in the area of the travelling mould is in counter flow to the direction of the movement of the cast strip.
  • a Cooling device for a process according to the invention has a storage tank for the cooling medium, a heating device and a pump, with pipes which connect the storage tank with the cooling device for indirectly cooling the strip of cast metal and a heat exchanger which is located in the backflow pipe transporting the coolant from the cooling device to the storage tank.
  • the cooling device has internals like wings, changes in the size and/or form of the cross section of the fluid channels, deviation plates, etc. which bring the coolant in turbulent state.
  • a twin roll casting machine for vertical strip casting is shown in principal, adopted with the devices necessary for cooling the rolls.
  • a difference to common twin roll casters is that the bearing of the rolls is arranged in that way, that the rolls are open, preferably on both ends, allowing a girder 9 to extend through the drums essentially parallel to their axis of rotation.
  • This girder 9 is fixed on a bearing pedestal 10 on each side of the drum. Feeding pipes 2 and backflow pipes 6 for the coolant are provided.
  • Fig. 2 shows the coolant supply device with a coolant storage tank 12, a coolant pump 13 that is connected to the feeding pipes 2 in Fig. 1 and the backflow pipes 6 of the coolant.
  • the backflow passes through an external heat exchanger 14, where the dissipation heat is transmitted to a secondary cooling cycle, and then back to the coolant storage tank.
  • Fig. 3 shows the cross section III-III of Fig. 4, being a cross section in the middle of the right drum in Fig. 1.
  • the cooling device consists of the feeding pipe 2, which is connected to a distribution chamber 3, the distribution chamber 3 ensures a defined pressure loss and hence an even distribution of the coolant along the length of the drum.
  • the coolant flows up through the heat exchanger 4, where it takes up the dissipation heat of the strip from the hot drum shell 1. Leaving the heat exchanger 4, the coolant flows into the collection chamber 5, where it is collected and fed into the backflow pipe 6, which leads out of the drum to the external heat exchanger 14, shown in Fig. 2.
  • the dissipation heat is transfused to a secondary cooling system, and may be used elsewhere in the mill for heating tasks. Finally, the coolant flows back into the coolant storage tank 12.
  • the coolant is stored in the tank 12 and pumped into the feeding pipe 2 by a pump 13.
  • This pump can be submerged in the coolant storage tank or be outside of the tank connected by a pipe, how it is shown in figure 2.
  • the pump can be a mechanical pump but also an electromagnetic pump, depending on the value of the necessary coolant flow rate, pump efficiency, investment costs and the coolant itself.
  • the selection of the pump and its installation is, knowing the invention and the details of the plant, no problem.
  • the internal heat exchanger 4 is pressed by hydraulic pistons 7 onto the inner surface of the caster shell 1.
  • the rotation of the internal heat exchanger 4 is prevented by the girders 8 and 9.
  • the hydraulic pistons 7 are supported by the girder 9.
  • the internal heat exchanger 4 is designed with installations that allow very high turbulence of the coolant leading to very high heat transfer coefficients.
  • Figure 4 shows the longitudinal section IV-IV of Fig. 3, depicting the right drum of Fig. 1.
  • the shell 1 of the drum is fixed on the hollow shafts 11, the position of the drum is fixed in the bearing 16.
  • a gear wheel 17 is provided, but the drive of the drums can also be installed in another way.
  • means for the tightening of the internal heat exchanger 4 against the shell 1 are provided. This may be done by one special packing ring, which is pressed between the circumference of the heat exchanger 4 and the inner side of the drum by the hydraulic pistons 7.
  • a more complex design would be to arrange two packing rings along the circumference of the heat exchanger 4 in a certain distance of about 5 mm to each other, so that the small chamber between the two packing rings can be filled by inert gas and hence prevents liquid cooling metal leaking out of the heat exchanger 4.
  • the packing ring has to be made of a material, that allows higher temperatures and do not wear out too fast by the friction between caster shell and heat exchanger 4.
  • the shell of the drum may consist of a copper alloy like Elbrodur B 95, or may comprise two hollow shells, where the outer shell is made of an copper alloy like Elbrodur B 95 or an other copper alloy allowing high heat withdrawal from the hot strip and the inner shell is a thin steel shell giving the drum the necessary stiffness.
  • the shell can have a top layer of wear resistant material on its outer as well as on its inner surface in order to ensure a longer lifespan.
  • the storage tank for the coolant may be equipped with an inert gas inlet 15 in order to ensure an inert atmosphere in the tank. Furthermore it may be advantageous to install a coolant refresh device that allows the regeneration of used, consumed coolant after a certain operation time.
  • the invention is applicable for strip casting of ferrous metals like steel and for nonferrous metals like copper, aluminium, and other non-ferrous metals and their alloys. It is possible to adapt existing plants according to the invention without great problems; In order to do so, it is only necessary to mount suitable containments which prevent the exit of coolant along the inner surface of the drum or belt.
  • the material of this casing has to withstand the temperature and chemical impact of the coolant as well as its dynamic forces, resulting from its density and flow. For the man skilled in the art of metal casting and knowing the invention, the selection of the necessary materials is no problem.
  • the used coolant in order to prevent the freezing of the device, it is preferred to heat all or at least most pipes and devices through which the coolant flows. Further, the pipes and devices should be mounted in inclined position. This ensures that, in case of a failure of the pump, the coolant flows by its weight back into the storage tank having a heating.
  • the advantages of the cooling concept according to the invention are: Easier cooling control, because the heat transfer number is very constant in comparison to that of cooling with water as coolant; Longer life time of the travelling mould, Higher casting rate, Smooth cast strip surface without surface defects; No or only a negligible inhomogeneous subsurface layer of the cast strip; Grain structure and segregation can be controlled by adjusting the coolant temperature and by coolant flow rate; Inline rolling of the cast strip, rod or wire is possible and safe energy costs for reheating.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Moulds For Moulding Plastics Or The Like (AREA)
EP06450056A 2006-04-12 2006-04-12 Bandgiessen Withdrawn EP1844880A1 (de)

Priority Applications (9)

Application Number Priority Date Filing Date Title
EP06450056A EP1844880A1 (de) 2006-04-12 2006-04-12 Bandgiessen
BRPI0711537-7A BRPI0711537A2 (pt) 2006-04-12 2007-04-11 fundição de tira
CA002647894A CA2647894A1 (en) 2006-04-12 2007-04-11 Strip casting
PCT/EP2007/003210 WO2007115827A1 (en) 2006-04-12 2007-04-11 Strip casting
CNA2007800131190A CN101484257A (zh) 2006-04-12 2007-04-11 薄带的铸造方法和装置
EP07724151A EP2010345A1 (de) 2006-04-12 2007-04-11 Bandgiessen
JP2009504636A JP2009533225A (ja) 2006-04-12 2007-04-11 ストリップ連続鋳造
US12/226,261 US20090314460A1 (en) 2006-04-12 2007-04-11 Strip Casting
NO20084271A NO20084271L (no) 2006-04-12 2008-10-13 Bandstoping

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP06450056A EP1844880A1 (de) 2006-04-12 2006-04-12 Bandgiessen

Publications (1)

Publication Number Publication Date
EP1844880A1 true EP1844880A1 (de) 2007-10-17

Family

ID=37076205

Family Applications (2)

Application Number Title Priority Date Filing Date
EP06450056A Withdrawn EP1844880A1 (de) 2006-04-12 2006-04-12 Bandgiessen
EP07724151A Withdrawn EP2010345A1 (de) 2006-04-12 2007-04-11 Bandgiessen

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP07724151A Withdrawn EP2010345A1 (de) 2006-04-12 2007-04-11 Bandgiessen

Country Status (8)

Country Link
US (1) US20090314460A1 (de)
EP (2) EP1844880A1 (de)
JP (1) JP2009533225A (de)
CN (1) CN101484257A (de)
BR (1) BRPI0711537A2 (de)
CA (1) CA2647894A1 (de)
NO (1) NO20084271L (de)
WO (1) WO2007115827A1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101265516B (zh) * 2008-04-23 2010-06-02 浙江佰耐钢带有限公司 一种钢带淬火工艺及所用的冷却介质
WO2010136403A1 (de) * 2009-05-28 2010-12-02 Mettop Gmbh Verfahren zur kuehlung eines metallurgischen ofens

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ITRM20070150A1 (it) * 2007-03-21 2008-09-22 Danieli Off Mecc Processo e impianto per la produzione di nastro metallico
MX367572B (es) 2012-02-02 2019-08-27 Proionic Gmbh Liquidos ionicos para enfriamiento en entornos de alta temperatura.
EP3599037A1 (de) 2018-07-25 2020-01-29 Primetals Technologies Germany GmbH Kühlstrecke mit einstellung der kühlmittelströme durch pumpen
CN114406215A (zh) * 2021-12-15 2022-04-29 钢铁研究总院 一种利用液态金属进行强制冷却的真空快淬冷却系统

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1098541A (en) * 1964-03-05 1968-01-10 Leonard Gordon Charles Tuck Method for the continuous casting of metal
FR2289271A1 (fr) * 1974-10-29 1976-05-28 Socometal Chemise de refroidissement interne de rouleaux et cylindre travaillant a toute temperature
JPS62101353A (ja) * 1985-10-25 1987-05-11 Kawasaki Steel Corp 中空鋳片の連続鋳造方法
US4671340A (en) * 1985-09-17 1987-06-09 Institut De Recherches De La Siderurgie Francaise Roller for continuous casting between rollers, with circulation of cooling fluid
JPS6330157A (ja) * 1986-07-24 1988-02-08 Mitsubishi Heavy Ind Ltd 冷却ドラム式帯板連続鋳造法
JPS63192541A (ja) * 1987-02-05 1988-08-09 Kawasaki Steel Corp 急冷薄帯製造用内部水冷スリ−ブ式ロ−ル
US5411075A (en) * 1993-08-31 1995-05-02 Aluminum Company Of America Roll for use in casting metal products and an associated method
GB2310155A (en) * 1996-02-16 1997-08-20 Ishikawajima Harima Heavy Ind Casting roll
EP1452252A1 (de) * 2003-02-28 2004-09-01 Hubert Dipl.-Ing. Sommerhofer Verfahren zum Stranggiessen

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63183759A (ja) * 1987-01-26 1988-07-29 Ishikawajima Harima Heavy Ind Co Ltd 移動鋳型式連鋳機のノズル
FR2723014B1 (fr) * 1994-07-29 1996-09-20 Pechiney Rhenalu Procede et dispositif de correction de l'ovalisation de cylindres de coulee continue de bande metallique
JPH091295A (ja) * 1995-06-13 1997-01-07 Hitachi Cable Ltd 連続鋳造装置のダムブロックガイド
DE10042078A1 (de) * 2000-08-26 2002-03-07 Sms Demag Ag Verfahren und Vorrichtung zum kontinuierlichen Gießen von Stahlband aus Stahlschmelze
JP2002086254A (ja) * 2001-07-02 2002-03-26 Toshiba Corp 金属材料の処理方法及び装置
JP4726385B2 (ja) * 2002-09-25 2011-07-20 シンフォニアテクノロジー株式会社 急冷鋳造装置

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1098541A (en) * 1964-03-05 1968-01-10 Leonard Gordon Charles Tuck Method for the continuous casting of metal
FR2289271A1 (fr) * 1974-10-29 1976-05-28 Socometal Chemise de refroidissement interne de rouleaux et cylindre travaillant a toute temperature
US4671340A (en) * 1985-09-17 1987-06-09 Institut De Recherches De La Siderurgie Francaise Roller for continuous casting between rollers, with circulation of cooling fluid
JPS62101353A (ja) * 1985-10-25 1987-05-11 Kawasaki Steel Corp 中空鋳片の連続鋳造方法
JPS6330157A (ja) * 1986-07-24 1988-02-08 Mitsubishi Heavy Ind Ltd 冷却ドラム式帯板連続鋳造法
JPS63192541A (ja) * 1987-02-05 1988-08-09 Kawasaki Steel Corp 急冷薄帯製造用内部水冷スリ−ブ式ロ−ル
US5411075A (en) * 1993-08-31 1995-05-02 Aluminum Company Of America Roll for use in casting metal products and an associated method
GB2310155A (en) * 1996-02-16 1997-08-20 Ishikawajima Harima Heavy Ind Casting roll
EP1452252A1 (de) * 2003-02-28 2004-09-01 Hubert Dipl.-Ing. Sommerhofer Verfahren zum Stranggiessen
WO2004076096A1 (en) * 2003-02-28 2004-09-10 So & So Sommerhofer Oeg Continuous casting method

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101265516B (zh) * 2008-04-23 2010-06-02 浙江佰耐钢带有限公司 一种钢带淬火工艺及所用的冷却介质
WO2010136403A1 (de) * 2009-05-28 2010-12-02 Mettop Gmbh Verfahren zur kuehlung eines metallurgischen ofens
CN102460051A (zh) * 2009-05-28 2012-05-16 奥超冶金优化有限公司 用于冷却冶金炉的方法

Also Published As

Publication number Publication date
CA2647894A1 (en) 2007-10-18
WO2007115827A1 (en) 2007-10-18
JP2009533225A (ja) 2009-09-17
EP2010345A1 (de) 2009-01-07
US20090314460A1 (en) 2009-12-24
CN101484257A (zh) 2009-07-15
NO20084271L (no) 2009-01-09
BRPI0711537A2 (pt) 2011-11-01

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