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
  • B22D11/0685—Accessories therefor for cooling the cast product during its passage through the mould surfaces by cooling the casting belts
• • 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
  • B22D11/0631—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 travelling straight surface, e.g. through-like moulds, a belt

Definitions

• the invention relates to a method for the close - to - net casting of strands of metal, in particular rectangular strands, wherein liquid metal is poured onto a revolving conveyor belt, with subsequent inline rolling and an associated device.
• liquid metal is poured through an opening in the wall of a horizontally movable supply hopper on the top of a horizontally circulating belt to solidify there. After solidification, the cast strip is passed directly to a rolling stand or rolling mill.
• EP 1 077 782 B1 describes a method for casting rectangular rectangular strands of metal, in particular steel, and then inline rolling out of the strand, with a material supply container via whose outlet nozzle the liquid metal is applied to the upper strand of a conveyor belt, on which it solidifies and is passed on to a rolling stand for deformation, with the following steps: a) before the start of casting: aa) the delivery point of the liquid metal onto the conveyor belt is roughly specified) the conveying speed of the conveyor belt becomes dependent on the desired rolling thickness and Rolling speed of the rolling mill set.
• a device for near-net shape casting of rectangular metal strands is known, in particular of steel, and then inline - rolling out of the strand, with an outlet nozzle having Metallzu 1500 actuallyer, a horizontally disposed conveyor belt and at least one subordinate mill, wherein the Materialzu 1500 suiter is connected to moving elements, with which this in horizontal, coaxial with the main axis of the conveyor belt in or against the conveying direction of the strand is movable and the Materialzu- supply container connected to an actuator, which is technically connected to a control device, to the measuring elements for detecting the position of the solidification of the strand and measuring elements for detecting the temperature of the rolling stock are connected.
• the prior art thus includes a method or a device in which the point of delivery of the metal to the conveyor belt is locally fixed or locally variable.
• the disadvantage of a locally fixed feed point is that the production spectrum is subject to a severe limitation. Only products with small changes in dimensions or material qualities can be manufactured. An improvement was achieved by a variable delivery point of the liquid metal on the conveyor belt. In such a method or such a device, however, there is the disadvantage that the cooling is not adapted to the variable conditions. It was recognized that the type of cooling and the position or spatial arrangement The cooling during strip casting, for example, influences the heat dissipation in such a way that there is a local overheating of the conveyor belt, which results in its failure. Furthermore, the effective heat transfer can be so low that sufficient solidification of the cast strip is achieved.
• the invention is therefore based on the object of specifying a method and a device in which or in which the production window or the production spectrum is extended. This involves casting different metals and grades, casting different product thicknesses and widths, and a wide casting speed variance to avoid the above drawbacks.
• the invention also relates to a device for carrying out the method according to the invention.
• the decisive advantage of the method according to the invention is that the intensity of the cooling corresponding to the largest heat transfer is designed so that the greatest cooling effect is achieved at the point of the first contact of the liquid metal with the conveyor belt and decreases downstream.
• the local variation of the feed point of the liquid metal on the conveyor belt in conjunction with an optimally adapted cooling or cooling arrangement a flexibilization of the production spectrum is achieved.
• the point at which the liquid metal comes into contact with the conveyor belt must be changed under certain boundary conditions such as different metal qualities, mass flow rates and the like in the casting direction.
• the intensity of the cooling is set by a local change of the cooling zone, seen in the transport direction.
• the zone of the conveyor belt which has the greatest cooling intensity is therefore correlated with the location of the exit of the liquid metal from the feed tank.
• a flexibilization of the effective cooling section or of the heat removal for expanding the production window is achieved. It can be poured more or less strongly to be cooled materials in various flow rates.
• a first embodiment provides that the nozzles are combined in several independent units.
• Each nozzle unit is assigned a separate pressure regulated water supply.
• the pressure in the following nozzle units is gradually reduced. The highest pressure at the point of application of the liquid metal ensures that the greatest cooling effect is achieved here.
• the pressure in the individual nozzle units is changed.
• the pressure with which the cooling medium is injected at the individual nozzle units on the underside of the upper run of the conveyor belt remains constant.
• the individual nozzle units are arranged so that the nozzle unit with the greatest cooling effect, ie the largest coolant flow, is always located where the liquid metal is applied to the conveyor belt. For this, the nozzle units are displaced or displaced locally.
• the parameters conveyor belt speed and metal quantity / time are also changed.
• the effective cooling length necessary for solidification is adapted to the metallurgical length.
• This process is carried out in various situations as follows, assuming a uniform supply of the liquid metal to the conveyor belt.
• V ⁇ r new Vir old + unit Z / l
• Vj r is the speed of the conveyor belt and V E in h ei t z / i is the speed of the unit Z / 1.
• the mass flow rate m is kept constant - on reaching the end position of the unit Z / 1, the conveyor belt speed v Tr is reduced again to the original value.
• m is the mass flow rate
• d is the thickness of the strand
• b is the width of the strand
• rho is the density of the liquid metal
• v is the velocity of the Z / 1 unit.
• V Tr new V Tr old V unit Z / 1
• the mass flow rate m is kept constant. Upon reaching the end position of the unit Z / 1, the conveyor belt speed v Tr is increased again to the original value.
• Type throughput of the plant e.g. Type throughput of the plant:
• a metal feed container 1 for liquid metal 2 is arranged above a conveyor belt 3.
• the conveyor belt 3 is deflected over two rollers 4 and 5. From an opening 6 in the metal feed container 1, liquid metal 2 reaches the upper side 7 of the upper run 8 of the conveyor belt 3. By a rotary movement of the rollers 4 and 5, the liquid metal 2 is led in the transport direction 9 to a rolling device (not shown).
• the liquid metal 2 must have formed a strand shell of sufficient strength when it leaves the conveyor belt 3 in the region of the roller 5.
• nozzles 11 are arranged in the region of the underside 10 of the upper run 8 of the conveyor belt 3. From the nozzles 11, a cooling medium such as water or the like is injected onto the underside 10 of the upper run 8.
• the nozzles 11 are arranged, for example, in four nozzles - segments 12, 13, 14, 15.
• Each nozzle segment 12, 13, 14, 15 has a separate pressure regulated water supply (not shown). This makes it possible that each nozzle segment 12, 13, 14, 15 can be subjected to different pressure.
• the highest pressure of the cooling water or the cooling medium is provided where the largest amount of heat has to be dissipated. This location corresponds to the point at which the liquid metal 2 impinges on the top 7. In Figure 1a, this location is on the left side. Therefore, the nozzle segment 12 is for example subjected to a pressure of 8 bar. As seen in the transport direction 8, the amount of heat to be dissipated becomes smaller, the nozzle segment 13 is reduced Pressure of for example 6 bar, the nozzle segment 14 with 4 bar and the nozzle segment 15 applied with 3 bar.
• the nozzles segment (in FIG. 1 b the nozzle segment and in FIG. 1 c the nozzle segments) which are located in front of the point at which the liquid metal 2 impinges on the top side 7 are also subjected to a reduced pressure.
• the pressures are individually adjustable at any time and are influenced by the above-mentioned boundary conditions such as metal quality, mass flow rate, etc.
• the cooling water or the cooling medium is supplied to the individual nozzle segments 16, 17, 18, 19, 20 under constant pressure.
• the supply can be done centrally for all nozzles - segments 16, 17, 18, 19, 20 or decentralized for each individual.
• the nozzles of the nozzle segments 16, 17, 18, 19, 20 are designed so that the cooling effect of the nozzle segments 16, 17, 18, 19, 20 is different. This can be achieved for example by different flow rates of the cooling medium.
• the nozzle segment 16, 17, 18, 19, 20 with the highest cooling effect is arranged where the liquid metal 2 reaches the conveyor belt 3. Since this location varies, the nozzle segments 16, 17, 18, 19, 20 can be interchanged or offset. In Figure 2a, the highest cooling effect in the left nozzle segment 16 is reached. As seen in the transport direction 9, the cooling effect in the following nozzle segments 17, 18, 19, 20 decreases.
• FIG. 2b the feeding point for the liquid metal 2 is shifted in the transport direction 9.
• the nozzle segment 16 known from FIG. 2 a is likewise displaced in the transport direction 9.
• the subsequent nozzle segments 17, 18, 19, 20 are each shifted by one parking space to the right.
• FIG. 2c shows a shift around a further parking space.
• the effective cooling length is adjusted to the metallurgical length.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Continuous Casting (AREA)
• Treatment Of Steel In Its Molten State (AREA)
• Metal Rolling (AREA)
• Wire Processing (AREA)

Priority Applications (6)

Applications Claiming Priority (2)

Publications (1)

Family

ID=36011709

Family Applications (1)

Country Status (9)

Cited By (1)

Families Citing this family (2)

Citations (7)

Family Cites Families (8)

• 2004
  • 2004-12-18 DE DE102004061080A patent/DE102004061080A1/de not_active Withdrawn
• 2005
  • 2005-12-16 US US11/793,112 patent/US20080000612A1/en not_active Abandoned
  • 2005-12-16 AT AT05850286T patent/ATE414579T1/de active
  • 2005-12-16 JP JP2007545963A patent/JP4922945B2/ja not_active Expired - Fee Related
  • 2005-12-16 WO PCT/EP2005/013571 patent/WO2006063847A1/de active Application Filing
  • 2005-12-16 ES ES05850286T patent/ES2314751T3/es active Active
  • 2005-12-16 AU AU2005315789A patent/AU2005315789A1/en not_active Abandoned
  • 2005-12-16 DE DE502005006026T patent/DE502005006026D1/de active Active
  • 2005-12-16 EP EP05850286A patent/EP1827735B1/de not_active Not-in-force
  • 2005-12-16 PL PL05850286T patent/PL1827735T3/pl unknown

Patent Citations (7)

Non-Patent Citations (3)

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