EP0173797A1 - Einrichtung und Verfahren zur Kühlung und Erstarrung von voll- oder halbkontinuierlichem Stranggussmaterial - Google Patents

Einrichtung und Verfahren zur Kühlung und Erstarrung von voll- oder halbkontinuierlichem Stranggussmaterial Download PDF

Info

Publication number
EP0173797A1
EP0173797A1 EP85105372A EP85105372A EP0173797A1 EP 0173797 A1 EP0173797 A1 EP 0173797A1 EP 85105372 A EP85105372 A EP 85105372A EP 85105372 A EP85105372 A EP 85105372A EP 0173797 A1 EP0173797 A1 EP 0173797A1
Authority
EP
European Patent Office
Prior art keywords
casting
fluidized bed
particles
cooling
flow
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Withdrawn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
EP85105372A
Other languages
English (en)
French (fr)
Inventor
Michael J. Pryor
Peter E. Sevier
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.)
Olin Corp
Original Assignee
Olin Corp
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
Priority claimed from US06/272,132 external-priority patent/US4434838A/en
Priority claimed from US06/272,136 external-priority patent/US4473105A/en
Priority claimed from US06/272,131 external-priority patent/US4441542A/en
Application filed by Olin Corp filed Critical Olin Corp
Publication of EP0173797A1 publication Critical patent/EP0173797A1/de
Withdrawn legal-status Critical Current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
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/124—Accessories for subsequent treating or working cast stock in situ for cooling
    • B22D11/1241—Accessories for subsequent treating or working cast stock in situ for cooling by transporting the cast stock through a liquid medium bath or a fluidized bed
    • 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
    • B22D11/01—Continuous casting of metals, i.e. casting in indefinite lengths without moulds, e.g. on molten surfaces
    • B22D11/015—Continuous casting of metals, i.e. casting in indefinite lengths without moulds, e.g. on molten surfaces using magnetic field for conformation, i.e. the metal is not in contact with a mould

Definitions

  • the process and apparatus are preferably used to more rapidly extract heat from molten material being cast so that the casting speed can be increased.
  • the present invention is particularly adapted for the casting of very thin strip cross sections from materials comprising reactive metals or alloys, semi-metals and semi-conductors, etc., which require the use of an inert cooling medium such as an inert gas.
  • U.S. Patent No. 3,735,799 to Karlson sets forth an electromagnetic casting apparatus wherein coolant is applied to the solidifying and solidified surface of the ingot.
  • a fluidized bed coolant application system is employed which is capable of providing high heat transfer rates.
  • the high heat transfer rates enable the casting rate to be markedly increased.
  • fluidized bed coolant application system of this invention has particular application with respect to electromagnetic casting wherein the material is molded by levitation and, therefore, without contact of a chill mold it could be applied to other forms of continuous and semi-continuous casting and for any desired material including conventional nonreactive metals and alloys,
  • a considerable body of art has developed with respect to the use of electromagnetic containment for the purposes of casting metals as in U.S. Patent No. 2,686,864 to Wroughton et al.
  • a typical commercial electromagnetic casting apparatus comprises a three- part mold consisting of a water cooled inductor, a non-magnetic screen, and a manifold for applying cooling water to the resultant casting.
  • Such an apparatus is exemplified in U.S. Patent No. 3,467,166 to Getselev et al.
  • Containment of the molten metal is achieved without direct contact between the molten metal and any component of the mold. Solidification of the molten metal is attained by the direct application of water from a cooling manifold to the solidifying shell of the casting.
  • fluidized beds as described in the aforenoted articles have found some metallurgical applications it is not apparent that the prior art has recognized the unique applicability of fluidized beds as a coolant application system in the continuous or semi-continuous casting of materials such as metals, semi-metals, semi-conductors, etc., particularly when such materials are reactive in nature.
  • Ultrasonic energy has been employed in a wide variety of applications in the chemical and metallurgical industry as exemplified in U.S. Patent Nos. 2,828,231 to Henry, 3,066,084 to Osterman et al., 3,194,640 to Nesh, 3,511,488 to Stubblefield, 4,167,424 to Jubenville et al. and 4,168,295 to Sawyer.
  • an apparatus and process for the casting of desired shapes, preferably thin strip shapes, at increased casting rates.
  • the apparatus and process employ an electromagnetic thin strip casting arrangement wherein the material being cast is levitated in both the sump and the strip forming portion of the casting unit. This provides improved purity in the resultant casting since interactions with refractories or other mold materials are substantially eliminated.
  • the coolant application system employs a fluidized bed of inert particles such as sand, Such a fluidized bed is capable of markedly higher heat transfer rates than a gas cooling system Further, such a fluidized bed since it utilizes a gas to provide fluidization is capable of utilizing an inert gas such as helium, argon, etc., which will not react with the material being cast. Therefore, the use of a fluidized bed coolant application system in accordance with this invention provides all the advantages of a gas coolant system with the further marked advantage of inproved heat transfer rates.
  • a control apparatus for the fluidized bed cooling system which determines the most upstream position at which the fluidized bed contacts the material being cast.
  • the control apparatus or system is adapted to adjust the pressure differential between the gas used to fluidize the bed and an opposing gas pressure. By adjusting the relative difference between the pressure of the fluidizing gas and the opposing gas pressure the surface of the fluidized bed which determines the upstream height of the bed can be moved upwards or downwards as desired as the pressure differential is either increased or decreased.
  • the cooling effectiveness of the fluidized bed in the region of the casting zone is augmented.
  • a flow enhancing means which can enhance the flow of the fluidized bed into the casting zone.
  • this is acconplished through the use of sound generators which generate sound waves moving in a direction so as to inpact the strip being cast near or at the casting zone.
  • the frequency of the sound waves may be selected as desired to provide the enhanced flow of the fluidized bed.
  • Alternative means for providing the enhanced flow could include fans or gas jets providing an enhanced gas flow direction directed at the casting zone.
  • an apparatus 10 and process are provided for casting, preferably in thin strip form, materials such as reactive metals, particularly those having a high melting point such as titanium, zirconium, vanadium, tantalum, molybdenum and tungsten as well as other metals, alloys, metalloids and semi-conductive materials such as silicon.
  • materials such as reactive metals, particularly those having a high melting point such as titanium, zirconium, vanadium, tantalum, molybdenum and tungsten as well as other metals, alloys, metalloids and semi-conductive materials such as silicon.
  • These materials are preferably cast under conditions employing inert atmospheres or vacuums to avoid the formation of excessive oxides.
  • the prior art approaches as described heretofore require sophisticated control of atmosphere in order to yield a clean uncontaminated thin strip product irrespective of the casting method.
  • the electromagnetic casting method is strongly preferred because of the absence of contact with a crucible or mold which eliminates the attendant contamination problems.
  • the prior art cooling approach employing gas cooling restricts the output of the casting machine making the process preferred for use only with extremely expensive materials such as high purity silicon. Much higher casting rates are desired not only for such high purity materials such as silicon but also for refractory high melting point metals such as the reactive metals described above.
  • an apparatus 10 has been devised for achieving significantly higher cooling rates in a continuous or semi-continuous casting apparatus than can be achieved by the approaches of the prior art. This is accomplished in accordance with the present invention through the use of a fluidized bed cooling apparatus 10.and process.
  • the apparatus 10 includes a casting chamber 11.
  • the casting chamber 11 surrounds an electromagnetic casting mold 12 which also supports in a levitated fashion a sump 13 of molten material.
  • the casting system further includes a means 14 for replenishing the material in the sump 13 as it is depleted in the casting operation, a cooling system 15 comprising a fluidized bed in accordance with the present invention, means 16 for transporting the resultant strip product S out of the casting chamber 11 and an isolation chamber 17 surrounding the casting mold 12 and replenishment system 14..
  • the casting chamber 11 and the isolation chamber 17 are provided with an inert gas atmosphere.
  • the inert gas may be any desired inert gas including helium, argon, etc.
  • the inert gas in the casting chamber 11 is supplied by the fluidized bed cooling system 15 and comprises the gas utilized in fluidizing the particle bed.
  • the inert gas supplied to the isolation chamber 17 is provided from a source 18 of inert gas which supplies both the isolation chamber 17 and the fluidized bed coolant system 15.
  • the inert gas source 18 can be any desired source such as a tank of compressed gas.
  • a blower 19 in the conduit 20 between the inert gas source 18 and the fluidized bed gas plenum 21 is used to provide a desired flow of inert gas necessary to fluidize a bed of preferably inert particles such as sand.
  • the sand particles are arranged in a lower portion of the casting chamber" 11 which comprises the fluidized bed chamber 22.
  • the gas flow which is created by the blower 19 through the fluidized bed plenum 21 passes through a screen 23 which forms the bottom of the fluidized bed chamber 22 and prevents sand particles from falling into the plenum 21.
  • the top surface 24 of the bed 25 will be at least as high as is desired for the fluidized bed to contact the resultant product S at an appropriate coolant application position.
  • the upper portion 26 of the casting chamber 11 flares out in order to provide a disengagement zone to provide separation of the bed particles and the gas.
  • the gas then flows out of the upper portion 26 of the casting chamber 11 via conduit 27 which is in communication with a cyclone separator 28 which separates any remaining entrained particles from the gas flow. Any particles so separated are returned to a particle supply conduit 29, The. gas from the separator 28 passes through a filter F to further remove entrained particles and then through a heat exchanger 30 to reduce its temperature back to its desired coolant temperature, A pump 31 then pumps the gas via conduit 32 back into the gas supply system 18.
  • Additional bed particles for addition to the fluidized bed 25 are maintained in a supply hopper 33 connected to the supply conduit 29.
  • the particles from the hopper 33 and the cyclone separator 28 fall into the supply conduit 29 which in turn is vibrator V actuated so that a desired amount of particles can be metered into the fluidized bed chamber 22 by vibrating the conduit 29 for a desired period of time.
  • a cooling jacket or plenum 34 for water or other desired coolant is provided in heat exchange contact with the surrounding lateral wall 35 of the fluidized bed chamber 22 extending from the screen 23 level to a height at which the fluidized bed no longer exists.
  • the fluidized bed 25 contacts this cooled wall 35 and is itself cooled so as to provide enhanced cooling of the resultant cast strip S.
  • cyclone separator 28 particle supply 33, inert gas. supply 18 and inert gas heat exchanger 30 are not presented as they can comprise any well-known design as are known in the art particularly the art noted in the background of this application. While a conduit 32 and heat exchanger 30 are provided for returning the gas emitted after filtering to the original gas supply 18 if desired the gas could merely be exhausted in a conventional fashion and only virgin inert gas utilized in the process.
  • the fluidized bed plenum 21 is sealed against the strip S by means of rubber wipers 36 as will be described hereafter.
  • a seal can be provided by a flow of gas from a suitable plenum 37 surrounding the strip and connects to a gas supply (not shown),
  • the electromagnetic containment system 12 may be any desired system for containing and forming the resultant strip product.
  • the inductor 38 which shapes the molten material into the desired thin strip shape defines a containment zone of 5 millimeters or less.
  • the shaping inductor 38 is preferably in communication with a sump 13 levitating inductor 39. A sump 13 of molten material is levitated by inductor 39 above the shaping inductor 38 so that all contamination with crucibles or the like is avoided.
  • a solid bar 40 o.f the material being cast is advanced by pinch rollers 41 and 42 at a rate controlled in a manner so as to replenish the sump.
  • a control system 43 senses an electrical parameter which is a function of hydrostatic pressure of the molten material and then energizes motor 44 to feed the solid material 40 into the melt at a rate so as to maintain a constant hydrostatic pressure and, therefore, a constant level in the sump.
  • the casting mold 12 and the replenishment system 14 are preferably arranged in an inner chamber 17 which is separately supplied with an inert gas,
  • the purpose of utilizing such an inner chamber 17 is to reduce the likelihood of contamination of the material being cast by the particles utilized in the fluidized bed. While it is preferred in accordance with this invention to utilize such an internal chamber 17 it . is not believed to be essential since it is thought that only a small percentage of particles would be entrained in the gas in the upper portion 26 of the casting chamber 11 and that those particles would not because of their small size and the surface tension of the molten material 13 become entrained in the resultant casting S.
  • the inner chamber 17 is provided with a slight positive pressure which prevents the entrance of the bed particles into the chamber 17.
  • the walls 45 of the inner chamber 17 are constructed of any suitable material. At least that portion 46 of the walls 45 which comes in contact with the inductors 38 and 39 are formed of an insulating material such as alumina.
  • the remaining portions of the inner chamber walls 45 which are not affected by the field of the inductors can be formed of any desired material such as a metal though preferably a non-magnetic metal is employed.
  • the resultant thin. strip casting S is withdrawn downwardly from the electromagnetic casting mold by means of withdrawal rolls 47, 48 and 49 and upon exiting the fluidized bed plenum it can be coiled upon large diameter drum 50. While it is preferred to coil the thin strip material S if desired the material may be cast in long uncoiled strip shapes by means of a conventional bottom block and moving ram approach.
  • a suitable starter strip (not shown) would be provided within the shaping inductor 38. This starter strip would be coiled at its opposite end on the drum 50. It would then be withdrawn as the casting is formed and when the actual material being cast reaches the drum 50 it in turn would be coiled on the drum.
  • the gas flow is directed generally vertically upward.
  • the width of the bed 25 as compared to the width of the electromagnetic mold system 12 is preferably large thereby the obstruction posed by the electromagnetic mold system 12 will comprise but a minor obstruction to the gas flow and it should be possible to have the fluidized bed 25 extend up into the casting zone 53 as in Figure 5,
  • the fluidized bed cooling system 15 is utilized as a secondary cooling system.
  • the primary cooling system comprises a gas cooling system 52 wherein a cooling gas flows upwardly past the casting zone 53 and then between the inductor 39 and the molten material sump 13 and outwardly therefrom.
  • the inductors 38 and 39 are preferably independently powered by conventional power supplies and control systems 43 and 43' preferably of the type described in the Yarwood et al (1) patent. While this control system and power supply arrangement is preferred in accordance with the present invention any desired control system and power supply could be employed.
  • the upper inductor 39 preferably levitates a sump 13 of molten material.
  • the lower inductor 38 is preferably shaped to provide a less than about 5 millimeter shaping zone.
  • a shield N. as shown in Figure 3 may if desired be employed to prevent excessive rounding out of the upper portion of the sump. However, it may be possible as in accordance with the teachings of the Pryor application that the shield N can be eliminated by suitably shaping the inductor 39.
  • the control system 43 for the upper inductor 39 also is utilized to control the advance of the solid material member or rod 40 into the molten material sump 13 in a manner so as to maintain the hydrostatic pressure exerted by the molten material substantially constant. This can be accomplished by utilizing an electrical parameter of the control system which varies in a manner corresponding about to the hydrostatic pressure.
  • the current in the inductor 39 or inductance of the inductor 39 are two such parameters that can be utilized.
  • the control system 43 is connected to a motor 44 which in turn is connected to the feed rolls 41 and 42 for advancing the material into the melt. In order to make a long casting run it is proposed to utilize a large replenishment member 40 and, therefore, as shown in Figure 2 more than one set of feed rolls 41 and 42 are preferably utilized in order to control the advancement.
  • the lower inductor 38 be powered at a relatively high frequency so as to provide minimal penetration depth of the induced current in the cast strip S.
  • the upper inductor 39 is preferably powered at a much lower frequency in order to save power consumption.
  • the fluidized bed cooling system 15 in this embodiment is a secondary cooling system
  • a suitable non-magnetic and non-conductive shield I is secured below the gas coolant application manifold 52.
  • the gas coolant manifold 52 surrounds the strip S and is arranged to direct a curtain of inert gas directly against the solidifying casting S in an upwardly manner so as to travel past the molten -material in the strip forming casting zone 53 and then past the molten material in the sump 13 and then into the inner chamber 17,
  • a suitable exhaust valve K is provided to maintain control of the pressure in the inner chamber 17 at a desired level. If the gas from the coolant manifold 52 .is adequate to provide the desired pressure of inert gas in the inner chamber 17 then it is unnecessary to supply additional gas from the inert gas supply 18 via conduit C as in Figure 1.
  • the connection between the inert gas supply 18 and the gas coolant manifold 52 has not been shown, however, it can be accomplished by any well-known conduit type connection and does not.form part of the invention herein.
  • the gas coolant manifold 52 also includes a port or ports to provide a gas flow. directed downwardly which serves to seal the gap between the non-magnetic Insulating shield I and the strip S being cast so as to prevent particles and gas from the fluidized bed 25 from entering into the casting zone 53 or the chamber 17.
  • the fluidized bed cooling system 15 includes an inert gas plenum 21 arranged below the fluidized bed 25 and separated therefrom by a suitable screen 23.
  • the plenum 21 is constructed in a conventional fashion to provide a substantially uniform flow of inert gas directed in an upward vertical direction.
  • the top surface 24 of the fluidized bed extends when fluidized at least to the height at which the bed is intended to impact the material being cast S. In Figure 2 the fluidized bed in operation extends somewhat beyond that height so that the shields I determine the height to which the bed 25 contacts the strip S.
  • the cooling effect of the fluidized bed 25 is a function of both the inert gas and the particle temperatures. Since the casting process is preferably continuous and the bed 25 will tend to heat up additional cooling of the bed 25 can be provided by a heat exchanger 34 comprising a surrounding water cooling jacket about the bed wall 35. There are many well-known alternative heat. exchangers for this purpose. For example, it could consist of coils (not shown) running through the bed. A flow of water through the jacket 34 can be established by means of a conventional pump and recirculating circuit arrangement (not shown). A heat exchanger (not shown) in the recirculating circuit can serve to reduce the temperature of the coolant before it flows into the input port 60 and flows about the jacket 34 and then out the output port 61 back to the heat exchanger and pump.
  • the portion 26 of the casting chamber 11 above the fluidized bed is flared outwardly to provide a disengagement zone to reduce the flow of,particles out of the chamber 11.
  • By controlling the flow of inert gas through the fluidized bed plenum 21 it is possible to fluidize the bed of particles to the desired height to provide contact to the material being cast S at the desired secondary position. Some particles will, of course, remain entrained in the inert gas and be exhausted through the port 27 of the casting chamber 11 to be processed and filtered out as described in reference to Figure 1. Replenishment of the particles in the fluidized bed 25 will be achieved in the manner described in accordance with Figure 1 via replenishment port 62.
  • a positive gas pressure would be established in the inner casting chamber 17 to prevent particles from flowing up into that chamber.
  • the gas cooling manifold 52 would be actuated to seal the inner casting chamber 17 against the fluidized bed cooling system 15.
  • the particles which at start up would be arranged on the screen would then be levitated to form the fluidized bed by providing the flow of inert gas through the fluidized bed plenum 21.
  • Water would be circulated through the cooling manifold .34.so that the walls of the fluidized bed system would act to reduce the temperature of the fluidized bed 25 so that it would remain as an effective coolant system even though the bed .particles are not circulated through the system.
  • the initial flushing of the inner casting chamber 17 with inert gas prior to start up can be supplied via conduit C and can be controlled by means of electrically operated valve 63.
  • the gas coolant manifold 52 is also actuated to provide a flow of gas both downwardly to seal the opening to . the fluidized bed chamber 22 and upwardly to provide a flow of gas about the material to be cast. If the pressure in the inner casting chamber 17 exceeds a desired level, the flow of gas from the inert gas supply through valve 63 can be reduced or eliminated. If necessary, the pressure can be further reduced by exhausting the excess inert gas through exhaust valve K for recirculation back to the inert gas supply 18.
  • the casting process electromagnetic or otherwise may be carried out in a conventional fashion once the cooling system is operational.
  • the particle materials used within the fluidized bed 25 are not critical as long as they have thermal and dimensional stabilities within the proposed conditions of use.
  • Purified sillica is an excellent material for use in the fluidized bed. If lower density materials are required to levitate the bed 25 ' under conditions of lower gas flow, less dense materials such as alumina or magnesia can be used. Other bed particles can be used as desired.
  • the use of the fluidized bed coolant system 15 as a secondary cooling system will not provide high casting rates for certain materials being cast. For example, silicon has such a low thermal conductivity in the solid state below a given temperature that the application of secondary cooling will have little effect on the casting rate. However, other materials when solidified will have adequate- thermal conductivity so that there might be an effect of secondary cooling on the casting rate. For such systems the use of a fluidized bed cooling as a secondary coolant application system should provide desired high casting rates.
  • the replenishment system 14 used for replenishing the molten material as it is cast comprises a particle type replenishment system 70 in place of the solid member 40.
  • the arrangements for powering the inductors 38 and 39 in this embodiment are essentially the same as that described in reference to the embodiment of Figures 1 to 3.
  • the replenishment system 70 which is illustrated in Figure 4 employs particulate materials, however, any desired replenishment system as, for example, the same type of solid member feed system 14 as in Figure 5 or a molten material feed system (not shown) if desired could be used.
  • the inductors 38 and 39 are secured at one end of the inner casting chamber 17 which is preferably formed of a non-magnetic, non-conductive material such as alumina.
  • the inductors 38 and 39 in this embodiment as in the previous one comprise an upper inductor 39 having a flared out region for supporting a flared out sump 13 of molten material and a lower inductor 38 having a very narrow zone for shaping the material into the desired thin strip shape.
  • the lower inductor 38 is flared outwardly and downwardly so as to provide a very thin edge of the inductor adjacent the strip forming section or zone of the mold.
  • This flared out -design also provides access for the fluidized bed 25 all the way up to the casting zone 53 and if desired, even up to the level of contact with the molten material just past the solidification front 75.
  • the upper level 76 of the fluidized bed 25 at the casting zone 53 is controlled by the pressure of the inert gas in the inner casting chamber 17' which is flow directed in opposition to the direction in which the inert gas and particles are flowing in the fluidized bed coolant system 15. This oppositely directed flow can be provided in any desired manner.
  • One gas flow can be provided from the source of inert gas 18 as in Figure 1 through conduit C which communicates with the internal casting chamber 17'. Since the inductors 38 and 39 are effectively sealed to the inner walls 77 of the chamber 17' the only path for the gas which flows into the chamber 17' is downwardly between the molten material sump 13 and the upper inductor 39 and then through the casting zone 53 toward the fluidized bed 25.
  • By properly balancing the pressure of the inert gas in the internal casting chamber 17' with the pressure of the inert gas in the fluidized bed 25 it is possible to control the height 76 of the fluidized bed at the casting zone 53. This height can be controlled either by controlling the pressure of the inert gas in the internal casting chamber 17' or independently controlling the pressure of the inert gas in the fluidized bed chamber 22 or a combination thereof.
  • the control system 78 connected to electrically operated valve 63.
  • this valve By adjusting this valve in a conventional manner it is possible to control the amount of the inert gas pressure in the internal casting chamber 17'. Therefore, if the pressure exerted by the fluidized bed 25 inert gas is essentially fixed it is possible to control the level 76 to which the fluidized bed coolant will rise in the casting zone 53.
  • the inert gas supplied through conduit C car be initially used to flush the system before start up. Thereafter, it can be supplemented by means of a gas application manifold 79 which directs the gas between the sump 13 of molten material and the sump supporting inductor 39.
  • the pressure of the gas in the internal casting chamber 17' can then be controlled either by controlling the pressure of the gas flowing from the manifold 79 or by allowing the manifold to flow at a constant flow and pressure and then controlling the combined gas pressure in the internal chamber 17' by means of the valve 63.
  • a preset or electrically operated exhaust flow control valve K' can be used to regulate the pressure in the chamber 17'. If electrically controlled, it would be connected to the control system 7 8.
  • the inert gas pressure in chamber 17' can be fixed and the pressure in bed chamber 22 varied by changing the inert gas flow rate by means of fan 19 whose speed is controlled by control system 80 as in Figure 1.
  • control system 80 as in Figure 1.
  • the counter pressure for regulating the height 76 of the bed at the casting zone 53 could be provided solely by the gas flowing from manifold 79 into the annulus between the containment inductor 39 and the sump 13. With this approach the pressure from the manifold 79 would be controlled by the control system 78.
  • pressurized cold inert gas is fed into the annulus or gap between the containment inductor 39 and the levitated molten material sump 13 at a pressure of p l .
  • the bed 25 is fluidized from below at a pressure p 2 .
  • P 1 and p 2 interact in the vicinity of the narrowest annulus of the shaping inductor 38, namely, the casting zone 53.
  • P 1 can be slightly higher than p 2 and provides a seal against the fluidized bed 25.
  • the surface 76 of the fluidized bed 25 can be moved upwards or downwards at will, as the difference between p 1 and p 2 is either decreased or increased, respectively.
  • This can provide a means for controlling the liquid solid interface position as an alternative to the arrangement of the Yarwood et al. (3) patent.
  • the use of the differential gas pressure to control the most upstream position of contact of the fluidized bed would likely include flow of the inert gas for fluidizing the bed into and through the annulus between the sump and the inductor.
  • the counter pressure exerted by the gas in the inner chamber most likely serves to reduce the flow rate of the fluidizing gas and thereby controls the position at which the fluidization of the particles ends which position corresponds to the most upstream position of the bed.
  • the particulate feed system 70 comprises a hopper 90 for replenishment material in particulate form.
  • the hopper is located in the outer casting chamber 11 and is connected via a conduit 91 which extends into the inner casting chamber 17'.
  • the conduit 91 or chute includes internally thereof a helical screw or spring type member 92 which feeds the particles from the supply hopper 90 to the molten material sump 13.
  • a vibrator 93 is utilized to vibrate the hopper.
  • a motor 94 is connected to the helical screw member 92 and is controlled by the control system 43" in a manner similar to that described in the previous embodiment. Namely, as described above, an electrical parameter corresponding about to the hydrostatic pressure of the molten material sump 13 is sensed and in response thereto the helical screw 92 is rotated a desired amount or at a desired rate in order to add solid particles to the molten material sump 13 at a rate which will maintain the hydrostatic pressure substantially constant to provide a substantially constant height for the stump 13.
  • the electromagnetic casting system 12 and the inner chamber 17 t are designed in a way so as to present a minimum obstruction to the gas flow for forming the fluidized bed 25.
  • this is accomplished through the use of sound generators 55 and 56 . which generate sound waves 100 moving in the direction so as to impact the strip S near the casting zone 53.
  • the transducers 55 and 56 which generate the sound waves 100 are located at the bottom outer corner of the fluidized bed chamber 35. In this manner they will pose a minimum obstruction to the flow of gas through the fluidized bed 25.
  • a more focused beam of sound waves 100' can be provided as in Figure 6.
  • the sound wave generators 55' and 56' which preferably generate ultrasound waves, are located just below the lower inductor 38 and they provide a focused beam of ultrasound impacting the material being cast S at the casting zone 53.
  • the transducers which make up the generators 55' and 56' would be subject only to heat radiation on the front surface and could be adequately cooled by any desired means (not shown) as, for example, a water cooling coil attached to the back of the transducers.
  • a stream of suspended particles can be directed against the strip S and molten material surface if desired due to the focused effect of the ultrasonic beam.
  • the ultrasonic generators 55 and 56' can comprise any desired well-known ultrasonic generating device including nickel-stack magneto- striction transducers or a piezoelectric transducer as, for example, the Mullard PXE ceramic element.
  • the sound waves may be of any desired frequency and may be generated in any desired manner.
  • an acoustical speaker like device could be employed, e.g., a moving coil and diaphram arrangement.
  • Sound waves having a frequency from about 10 hertz to about 15 megahertz should be employable for providing the desired flow enhancement.
  • the frequency which is selected is low enough to accelerate the particles to provide the desired directional enhancement.
  • Sound waves 100 or 100' represent a preferred approach for enhancing the cooling effect in the "V"-shaped cavity formed by the lower inductor 38.
  • small fans 105 are employed to provide a preferred flow direction for the fluidized bed 25 so that the bed will be efficiently operative in the casting zone region 53.
  • gas jets 106 are generally directed towards the casting zone region 53 to provide the enhancement of the fluidized bed 25 action in that region.
  • the gas flow created by the fans 105 or jets 106 must be limited in a manner so as not to destroy the fluidized character of the bed. Therefore, the flow rates should be selected as desired..in a manner to provide flow enhancement without destroying the fluidized nature of the bed.
  • the present invention when employing electromagnetic casting is applicable to the full range of materials to which such a system can be applied and, in particular, it is applicable to materials which are electrically conductive in the molten state.
  • it is applied to metals, metalloids, semi-conductors, alloys, etc. It has particular application to materials such as silicon and germanium as well as to reactive metals and alloys.
  • casting zone 53 refers generally to the containment and shaping region defined by the inductor 38.
  • the coolant application zone can extend over the whole casting zone 53 or it can be limited to only the solidified surface of the casting S or in any manner desired.
  • the particle sizes of the fluidized bed particles and the flow rates of the inert gas for fluidizing the particles may be set as desired in accordance with well-known principals as evidenced by the prior art noted in the background of this application. Accordingly, any desired conventional particle size or gas flow rate could be used in accordance with the present invention.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
EP85105372A 1981-06-10 1982-06-09 Einrichtung und Verfahren zur Kühlung und Erstarrung von voll- oder halbkontinuierlichem Stranggussmaterial Withdrawn EP0173797A1 (de)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
US06/272,132 US4434838A (en) 1981-06-10 1981-06-10 Apparatus and process for cooling and solidifying continuous or semi-continuously cast material
US06/272,136 US4473105A (en) 1981-06-10 1981-06-10 Process for cooling and solidifying continuous or semi-continuously cast material
US272132 1981-06-10
US06/272,131 US4441542A (en) 1981-06-10 1981-06-10 Process for cooling and solidifying continuous or semi-continuously cast material
US272131 1981-06-10
US272136 1981-06-10

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
EP82105067.1 Division 1982-06-09

Publications (1)

Publication Number Publication Date
EP0173797A1 true EP0173797A1 (de) 1986-03-12

Family

ID=27402446

Family Applications (3)

Application Number Title Priority Date Filing Date
EP82105067A Ceased EP0066896A1 (de) 1981-06-10 1982-06-09 Einrichtung und Verfahren zum Kühlen und Erstarren von voll- oder halb-kontinuierlichem Stranggussmaterial
EP85105373A Withdrawn EP0176660A1 (de) 1981-06-10 1982-06-09 Einrichtung und Verfahren zur Kühlung und Erstarrung von voll- oder halbkontinuierlichem Stranggussmaterial
EP85105372A Withdrawn EP0173797A1 (de) 1981-06-10 1982-06-09 Einrichtung und Verfahren zur Kühlung und Erstarrung von voll- oder halbkontinuierlichem Stranggussmaterial

Family Applications Before (2)

Application Number Title Priority Date Filing Date
EP82105067A Ceased EP0066896A1 (de) 1981-06-10 1982-06-09 Einrichtung und Verfahren zum Kühlen und Erstarren von voll- oder halb-kontinuierlichem Stranggussmaterial
EP85105373A Withdrawn EP0176660A1 (de) 1981-06-10 1982-06-09 Einrichtung und Verfahren zur Kühlung und Erstarrung von voll- oder halbkontinuierlichem Stranggussmaterial

Country Status (2)

Country Link
EP (3) EP0066896A1 (de)
CA (1) CA1186479A (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2169230B (en) * 1985-01-04 1989-06-14 Pont A Mousson Method and installation for the manufacture of pipes from spheroidal graphite cast-iron having a controlled structure

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3114628A1 (de) * 1980-04-11 1982-02-11 Olin Corp., 62024 East Alton, Ill. Verfahren und vorrichtung zum elektromagnetischen giessen

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3461943A (en) * 1966-10-17 1969-08-19 United Aircraft Corp Process for making filamentary materials
US3543831A (en) * 1967-01-09 1970-12-01 United Aircraft Corp Electrostatic coatings
SE346234B (de) * 1970-03-03 1972-07-03 Asea Ab
US3685568A (en) * 1971-03-01 1972-08-22 United States Steel Corp Method of quenching metal filament in froth
FR2367561A1 (fr) * 1976-10-15 1978-05-12 Michelin & Cie Perfectionnements aux install
FR2393635A1 (fr) * 1977-06-06 1979-01-05 Michelin & Cie Procede de fabrication de fil metallique ondule pour armer des materiaux composites
JPS5474698A (en) * 1977-11-28 1979-06-14 Univ Tohoku Superconductive thin band and method of fabricating same

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3114628A1 (de) * 1980-04-11 1982-02-11 Olin Corp., 62024 East Alton, Ill. Verfahren und vorrichtung zum elektromagnetischen giessen

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2169230B (en) * 1985-01-04 1989-06-14 Pont A Mousson Method and installation for the manufacture of pipes from spheroidal graphite cast-iron having a controlled structure

Also Published As

Publication number Publication date
EP0176660A1 (de) 1986-04-09
EP0066896A1 (de) 1982-12-15
CA1186479A (en) 1985-05-07

Similar Documents

Publication Publication Date Title
US4441542A (en) Process for cooling and solidifying continuous or semi-continuously cast material
US4473105A (en) Process for cooling and solidifying continuous or semi-continuously cast material
US4915723A (en) Apparatus for casting silicon with gradual cooling
EP0069270B1 (de) Verfahren und Vorrichtung zur Erzeugung halbfesten thixotropen Legierungsbreis
EP0114988B1 (de) Metallstranggussverfahren
US4004631A (en) Electromagnetic casting apparatus
EP0120684B1 (de) Schrotteinschmelzen und Einführen von festem Material in geschmolzenes Metall
GB2099189A (en) Molten metal level control in continuous casting
US4434838A (en) Apparatus and process for cooling and solidifying continuous or semi-continuously cast material
KR100330509B1 (ko) 금속스트립주조방법및그연속주조장치
EP0173797A1 (de) Einrichtung und Verfahren zur Kühlung und Erstarrung von voll- oder halbkontinuierlichem Stranggussmaterial
US5427173A (en) Induction skull melt spinning of reactive metal alloys
JPS6338535A (ja) 反応性金属の製造装置
JPH01264920A (ja) シリコン鋳造装置
JP2002146447A (ja) 非鉄金属用脱ガス装置
US5084089A (en) Method for in-line induction heating of molten metals for supplying continuous casting devices
Garnier The Clifford Paterson Lecture, 1992 Magentohydrodynamics in material processing
US4530394A (en) Controlled water application for electromagnetic casting shape control
JP2889928B2 (ja) 磁気浮揚式連続鋳造装置
JP2926961B2 (ja) 金属の連続的溶解および鋳造装置
EP0022566B1 (de) Verfahren und Vorrichtung zum elektromagnetischen Formen geschmolzener Metalle oder Legierungen, Kühlmittelverteiler für das elektromagnetische Giessen
JPH11188464A (ja) 溶融金属の連続鋳造方法およびその装置
CN118543795B (zh) 金属液磁悬浮连铸在线加工生产线控制方法
JPH03180432A (ja) 金属の溶解方法および溶解装置
JP3966054B2 (ja) 鋼の連続鋳造方法

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

AC Divisional application: reference to earlier application

Ref document number: 66896

Country of ref document: EP

AK Designated contracting states

Kind code of ref document: A1

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

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

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19861113

RIN1 Information on inventor provided before grant (corrected)

Inventor name: SEVIER, PETER E.

Inventor name: PRYOR, MICHAEL J.