Applying Electromagnetic Stirring Force To Molten Metal Within Mold Or Product Patents (Class 164/468)
  • Patent number: 5178204
    Abstract: A method and apparatus for rheocasting (slurry casting) molten metal employ a stirring chamber located upstream of a casting mold. Electromagnetic stirring is employed in both the stirring chamber and the casting mold. Structure is provided for minimizing secondary recirculating flows in the molten metal as it flows downstream through the apparatus, for preventing hangers and for eliminating the columnar dendritic zone at the periphery of the casting. The efficiency of utilization of the magnetic field is optimized as is the agitation required for producing a desired fine, spheroidal, degenerate dendritic grain structure in the solidified casting.
    Type: Grant
    Filed: April 8, 1992
    Date of Patent: January 12, 1993
    Inventors: James E. Kelly, Kenneth E. Blazek, Kenneth P. Young
  • Patent number: 5134628
    Abstract: In a direct-current arc furnace having a bottom electrode (2), electromagnetically and/or chemically induced bath agitations are substantially eliminated by an electromagnet (9) arranged under the vessel bottom (7). In this way the stability of the bottom electrode (2) is considerably increased. The electromagnet (9) is preferably integrated into the electrical supply of the furnace and serves as a smoothing choke.
    Type: Grant
    Filed: April 19, 1991
    Date of Patent: July 28, 1992
    Assignee: ASEA Brown Boveri Ltd.
    Inventor: Sven-Einar Stenkvist
  • Patent number: 5095969
    Abstract: An electromagnetic agitating method in a casting mold for the continuous casting of a slab in which electromagnetic agitating devices for generating a thrust force in the slab drawing direction are arranged at at least an inner wide surface of both inner and outer surfaces of the slab casting mold in a bending type continuous casting machine. The thrust force in the drawing direction applied to molten steel within the casting mold by the electromagnetic agitating devices is substantially applied from the narrow surface of the casting mold toward the center thereof in a range except a predetermined length in order to perform an electromagnetic agitation of molten steel.
    Type: Grant
    Filed: June 27, 1990
    Date of Patent: March 17, 1992
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Toshiyuki Soejima, Tadashi Saito, Nobuyuki Genma, Masayasu Kimura, Yasuo Kaihara
  • Patent number: 5088547
    Abstract: An electromagnetic stirrer for stirring the molten core of a continuously cast strand has a casing. The casing accommodates a body of oil as well as electromagnetic stirring coils which have respective magnet cores and are immersed in the oil. A system of cooling pipes extends into the oil and has water inlets and water outlets. The stirrer may be constructed as a unit with a continuous casting mold and, in such an event, the water inlets are connected to a source of mold cooling water while the water outlets function to discharge or recycle the water. Alternatively, the stirrer may be disposed in the secondary cooling zone. Here, the water inlets are connected to a source of secondary cooling water for the strand and the water outlets are in communication with spray nozzles which serve to spray the strand with the secondary cooling water.
    Type: Grant
    Filed: August 24, 1990
    Date of Patent: February 18, 1992
    Assignee: Concast Standard AG
    Inventor: Markus Schmid
  • Patent number: 5085265
    Abstract: An apparatus for continuous casting of molten steel comprises a continuous casting mold; an electromagnetic stirring coil, which rotates and fluidizes molten steel inside the mold and which is installed outside the mold; and a screen of ferromagnetic substance positioned between the mold and the electromagnetic stirring coil at a height including a level of meniscus. A method for continuous casting of molten steel comprises the steps of pouring molten steel into a continuous casting mold; applying an electromagnetic force to the molten steel in the mold by means of an electromagnetic coil installed outside the continuous casting mold; and shielding said electromagnetic force by means of a screen of ferromagnetic substance installed between the mold and electromagnetic coil at a height including a level of meniscus.
    Type: Grant
    Filed: March 20, 1991
    Date of Patent: February 4, 1992
    Assignee: NKK Corporation
    Inventors: Hironori Yamamoto, Chitoshi Matsumura, Kentaro Mori
  • Patent number: 5063991
    Abstract: Energetic cooling of the product is performed during continuous casting when, at the core, the product is in a phase of pasty solidification so that the differential thermal contraction between the mushy core and the already completely solidified outer shell produces a squeezing effect of the core by the shell. To this end, means for cooling the product are arranged on the casting machine at the end section of the metallurgical length. The process makes it possible to reduce, and even to avoid, the formation of inner cracks during cooling of the cast product which would lead to the presence of segregated areas in the axial zone. It is applied advantageously to the casting of steels reputed to be difficult to cast continuously, such as steels with a long solidification range whose carbon content is from 0.25 to 1.5%.
    Type: Grant
    Filed: August 3, 1990
    Date of Patent: November 12, 1991
    Assignee: IRSID
    Inventors: Manuel Bobadilla, Jean-Marc Jolivet, Michel Martinot
  • Patent number: 5033534
    Abstract: A method for continuous casting of steel comprises charging molten steel from a tundish into a mold through exit ports of an immersion nozzle, introducing a magnetic field vertically to a flow of the molten steel from the exit ports by the use of at least a pair of direct current magnets which are arranged on the outer side of copper plates on the wide side of the mold, the immersion nozzle being placed between the direct current magnets and polarities of magnetisms on the top side of the magnets being the same, and casting the molten steel at a predetermined casting rate. One magnetic pole of the direct current magnet is positioned at an upper end of copper plate on the wide side of the mold and the other magnetic pole being positioned at lower than the exit port of the immersion nozzle and on the outer side of copper plate on the wide side of the mold. The immersion nozzle has two exit ports, each of which has an angle of 15.degree. to 45.degree. downward.
    Type: Grant
    Filed: March 2, 1990
    Date of Patent: July 23, 1991
    Assignee: NKK Corporation
    Inventors: Mikio Suzuki, Toru Kitagawa, Shinobu Miyahara, Akio Nagamune, Yoshiyuki Kanao, Norio Ao, Hironori Yamamoto
  • Patent number: 5027883
    Abstract: The process for the continuous casting of thin metal products, particularly steel, products, of the type according to which the molten metal is poured into a continuous-casting ingot mold of elongated section, from which the partially solidified metal is continuously withdrawn and the thickness of the product emerging from the ingot mold is reduced by means of squeezing rolls (4, 4'), comprises the steps of (a) detecting whether the liquid phase tip is located upstream or downstream of the squeezing rolls, (b) applying between the squeezing rolls, a variable magnetic field to the core of the product, while matching the action of the magnetic field to the detected position of the liquid phase tip.
    Type: Grant
    Filed: April 3, 1990
    Date of Patent: July 2, 1991
    Assignee: Techmetal Promotion (Societe Anonyme)
    Inventors: Roger Ventavoli, Daniel Neyret
  • Patent number: 5027884
    Abstract: A process and apparatus for producing thin metal products by continuous casting. The apparatus comprises an ingot mold (2) and squeezing rolls (6, 6') intended to cause, by reduction of the thickness of product, closing of the solidification pool. The separation force (F) exerted on the squeezing rolls by the product is measured and a variable magnetic field, matched to the separation force so that the latter does not exceed over a long period a predetermined upper limit value representing the force that the squeezing rolls can tolerate temporarily without damage, is applied to the core of the still molten product by inductors (8, 8') housed in, or upstream of, the squeezing rolls.
    Type: Grant
    Filed: April 3, 1990
    Date of Patent: July 2, 1991
    Assignee: Techmetal Promotion
    Inventors: Roger Ventavoli, Daniel Neyret
  • Patent number: 5025852
    Abstract: There is disclosed a continuous casting mold for casting billets and blooms including a stirring means to produce a rotating electromagnetic field of force. It is sought to be able to use a continuous casting mold of this type facultatively with free-stream casting or with immerged-tube casting. To this end, the continuous casting mold includes at least two stirring means arranged one above the other in height. At least one the stirring means is arranged in the upper half of the continuous casting mold and at least one of the stirring means is arranged in the lower half of the continuous casting mold. The at least two stirring means are electrically connected and operable independently of one another.
    Type: Grant
    Filed: June 25, 1990
    Date of Patent: June 25, 1991
    Assignee: Voest-Alpine Industrieanlagenbau
    Inventor: Karl Mayrhofer
  • Patent number: 5025853
    Abstract: A continuous casting apparatus has a mold table which is supported by an oscillator and carries a continuous casting mold. The mold is provided with a casting passage having an inlet end for molten material and an outlet end for a continuously cast strand. An electromagnetic stirrer for the molten material is mounted on the mold table independently of the mold adjacent to the outlet end thereof.
    Type: Grant
    Filed: January 10, 1990
    Date of Patent: June 25, 1991
    Assignee: Concast Standard AG
    Inventor: Markus Schmid
  • Patent number: 5017244
    Abstract: The present invention relates to copper-iron-nickel alloys having utility in electronic applications because of their low coefficients of expansion and high thermal conductivities. Alloys in accordance with the present invention consist essentially of from 10% to about 80% copper and the balance iron plus nickel with the ratio of iron to nickel being in the range of from about 1.5:1 to about 2.0:1. Preferred alloys have an iron to nickel ratio in the range of from about 1.6:1 to about 1.9:1. The process includes casting the alloy and treating the iron-nickel phase of alloy to minimize its surface volume. The treating step may comprise speroidizing the iron-nickel phase or applying an electromagnetic stirring force to the alloy during the casting step.
    Type: Grant
    Filed: December 14, 1988
    Date of Patent: May 21, 1991
    Assignee: Olin Corporation
    Inventors: Ashok Sankaranarayanan, Jacob Crane, Julius C. Fister
  • Patent number: 4993477
    Abstract: A continuous metal casting system in which the feed of molten metal is controlled by means of a linear induction motor capable of producing a magnetic traveling wave in a duct that connects a reservoir of molten metal to a caster. The linear induction motor produces a traveling magnetic wave in the duct in opposition to the pressure exerted by the head of molten metal in the reservoir so thatp.sub.c =p.sub.g -p.sub.mwhere p.sub.c is the desired pressure in the caster, p.sub.g is the gravitational pressure in the duct exerted by the force of the head of molten metal in the reservoir, and p.sub.m is the electromagnetic pressure exerted by the force of the magnetic field traveling wave produced by the linear induction motor. The invention also includes feedback loops to the linear induction motor to control the casting pressure in response to measured characteristics of the metal being cast.
    Type: Grant
    Filed: March 6, 1989
    Date of Patent: February 19, 1991
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventor: Walter F. Praeg
  • Patent number: 4986340
    Abstract: Melt fed to a continuous casting mold is slowed and spread by a magnetic field acting in the path of the inflowing melt stream. The magnetic field, which is either a static field powered by continuous current, a field powered by permanent magnets, or a field powered by low-frequency alternating current, is applied at at least two spaced-apart locations, either in two separated cast strands or at spaced locations across a wide single strand.
    Type: Grant
    Filed: July 30, 1990
    Date of Patent: January 22, 1991
    Assignee: Asea Aktiebolag
    Inventor: Jan E. Eriksson
  • Patent number: 4974660
    Abstract: The process and apparatus according to the invention relates to the continuous casting of hollow bodies of metals such as aluminium, copper, steels of all types, or other metals or alloys. The process comprises introducing a liquid metal into an annular space between an outer mold and an inner mandrel, the liquid metal being subjected in the vicinity of the mandrel to the action of a movable magnetic field which entrains it in an upward direction. The magnetic field is preferably generated by a magnetic rotor which is disposed in the mandrel. The process is used in particular for producing blanks intended for the production of non-welded pipes and tubes.
    Type: Grant
    Filed: May 1, 1989
    Date of Patent: December 4, 1990
    Assignee: Vallourec
    Inventors: Roland Ernst, Marcel Garnier, Michel Giroutru, Andre Gueussier, Rene Moreau, Pierre Peytavin
  • Patent number: 4964455
    Abstract: A method is disclosed for making thixotropic metal products by continuous casting by pouring liquid metal into a mold with a movable end and having upstream and downstream portions. The upstream portion has a wall made of a heat insulating material at least at its inner surface to form a hot zone, and the downstream portion has a wall made at least partially of a heat conducting material to form a cold zone. A movement is imparted to the solidifying liquid to cause circulation between the cold zone and the hot zone in order to bring about surface remelting of crystals formed in the cold zone and degeneration of dendrites.
    Type: Grant
    Filed: June 6, 1989
    Date of Patent: October 23, 1990
    Assignee: Aluminum Pechiney
    Inventor: Jean-Luc Meyer
  • Patent number: 4957156
    Abstract: There is disclosed a continuous casting mold for casting billets and blooms including a stirring means to produce a rotating electromagnetic field or force. It is sought to use a continuous casting mold of this type facultatively with free-stream casting or with immerged-tube casting. The continuous casting mold includes at least one stirring means which is displaceable over the height of the continuous casting mold and is fixable in different height positions.
    Type: Grant
    Filed: June 5, 1989
    Date of Patent: September 18, 1990
    Assignee: Voest-Alpine Industrieanlagenbau Gesellschaft m.b.H.
    Inventor: Karl Mayrhofer
  • Patent number: 4949778
    Abstract: In an immersion nozzle for continuous casting, at least one portion of reduced a sectional area of passage for molten metal is formed near to the bottom of the nozzle and plural discharge ports symmetrically arranged with respect to the axis of the nozzle are arranged above and below the reduced sectional area portion in the longitudinal direction of the nozzle. Further, molten metal is continuously cast by using the above immersion nozzle together with a static magnetic field.
    Type: Grant
    Filed: December 13, 1988
    Date of Patent: August 21, 1990
    Assignee: Kawasaki Steel Corporation
    Inventors: Kenji Saito, Tsutomu Nozaki, Yukio Oguchi, Kenichi Sorimachi, Hakaru Nakato, Haruji Okuda, Koji Hosotani, Katsuo Kinoshita, Kenji Murata
  • Patent number: 4934447
    Abstract: Device to intensify the magnetic field in an ingot mould, the device cooperating with an ingot mould body (10) and with a means (11) which is positioned outside an outer jacket (14) of the ingot mould body (10) and generates a magnetic field, whereby independent, replaceable auxiliary extension pole pieces (18) stretching substantially towards a crystallizer (12) are comprised within outer jacket (14) of the mould body (10) in correlation with pole pieces (16).
    Type: Grant
    Filed: November 15, 1988
    Date of Patent: June 19, 1990
    Assignee: Danieli & C. Officine Meccaniche SpA and Ceda SpA Costruzioni Elettromeccaniche e Dispositivi d'Automazione
    Inventor: Lorenzo Ciani
  • Patent number: 4933005
    Abstract: A static high intensity magnetic field is applied to electromagnetically-stirred molten metal to minimize turbulence in the molten metal. One application of the invention is to minimize meniscus distortions and/or surface disturbances produced by the electromagnetic stirring at a free surface. Another application is to improve laminar flow in the entrance to horizontal molds.
    Type: Grant
    Filed: August 21, 1989
    Date of Patent: June 12, 1990
    Inventors: Joseph A. Mulcahy, Julian Szekely
  • Patent number: 4930207
    Abstract: A method of continuous compression forging, with a compression forging anvil, the final solidified region of cast steel drawn out from a mold for continuously casting, comprising the step of: compressing said cast steel with said anvil at a compressing cycle which meets the following conditions: ##EQU1## where t: the compressing cycle (sec), .delta.: the overall thickness reduction, Vc: the casting speed (mm), D: the cast steel thickness before compression forging, .theta.: the inclination angle (.degree.) with respect to the flat surface of the anvil.
    Type: Grant
    Filed: May 24, 1989
    Date of Patent: June 5, 1990
    Assignee: Kawasaki Steel Corp.
    Inventors: Shinji Kojima, Toshitane Matsukawa, Hisakazu Mizota, Susumu Yuhara, Yoshio Yoshimoto, Toshio Fujimura, Kunihiro Ito
  • Patent number: 4924585
    Abstract: A segregation preventive or eliminative operation in a continuous casting process is performed under the following conditions:The solidified/unsolidified ratio of the solidifying block is in a range of 0.5:1 to 0.9:1;The ratio between the overall compression .delta. (mm) versus thickness of the unsolidified area in the block (d mm) is greater than or equal to 0.5 or the thickness (d mm) of the unsolidified layer in the solidifying block is: ##EQU1## where D is the thickness of the block before compression. Casting speed may be controlled according to thickness of the solidifying shell at or near a crater end. Preferably, electromagnetic stirring is performed before performing compression forging.
    Type: Grant
    Filed: April 21, 1989
    Date of Patent: May 15, 1990
    Assignee: Kawasaki Steel Corp.
    Inventors: Takuo Imai, Shinji Kojima, Toshitane Matsukawa, Toshio Fujimura
  • Patent number: 4909306
    Abstract: At least two magnetic induction elements operated with alternating current are disposed successively in the longitudinal direction at the guide for a strand of a continuous casting plant, and in particular for a continuous steel casting plant, to provide a stirring mechanism. Each induction element is connected to its own phase (R, S, T, N) of the at least two phase alternating current and the phases (R, S, T, N) are shifted with respect to each other by a phase angle of from about 0 to 180 degrees. In order to avoid the formation of a continously uniformly directed circulating current of metal despite a simple and sturdy stirring provision and without the presence of additional switching circuits, the phases (R,S,T) generate in each case electromagnetic forces under formation of a magnetic alternating field at at least two neighboring induction elements, where the momentary value differences and the directional differences correspond to a phase shift of .PHI.+180 degrees.
    Type: Grant
    Filed: October 19, 1984
    Date of Patent: March 20, 1990
    Assignee: Voest-Alpine International Corporation
    Inventors: Wolfgang Polanschutz, Luzian Pochmarski, Alfred Moser
  • Patent number: 4877079
    Abstract: A casting mold in a continuous casting line has a counterflow electromagnetic stirring (CEMS) apparatus disposed about the mold. The CEMS apparatus includes electrically-conductive coils arranged in first and second groups of adjacent coils with the coils connected together in predetermined phase relationships for generating side-by-side magnetic fields in molten metal flowing through the casting mold. The first and second groups of adjacent coils are disposed respectively along respective halves of the casting mold with the coils in the first group generating one magnetic field and the coils in the second group generating the other magnetic field. The magnetic fields so generated in the molten metal move in counterrotating relation to one another about respective spaced axes extending generally parallel to one another and to the longitudinal axis of the casting mold.
    Type: Grant
    Filed: October 14, 1988
    Date of Patent: October 31, 1989
    Assignee: Westinghouse Electric Corp.
    Inventors: Lawrence J. Long, James A. Henrickson
  • Patent number: 4852635
    Abstract: A method of electromagnetically stirring molten metal in an unsolidified portion of a continuously cast strand by a magnetic field formed by applying alternating current to at least two exciting coils, the method comprising: supplying to one of the exciting coils a first alternating current of a frequency in the range of 1-60 Hz and to the other one of the exciting coils a second alternating current with a frequency difference in the range of 0.03-0.25 Hz from the first alternating current to form a varying composite magnetic field thereby to induce stirred movement of varying direction and intensity in the molten metal.
    Type: Grant
    Filed: November 8, 1984
    Date of Patent: August 1, 1989
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Toshiyasu Onishi, Kenzo Ayata, Hiroshi Takagi, Yasuo Suzuki, Yasuhiko Ohta, Takao Shiozawa, Koichi Fujiwara, Masakazu Itashiki
  • Patent number: 4834168
    Abstract: The inductor comprises two portions each having its own casing (3, 4) and capable of pivoting about a hinge (7), thereby enabling the inductor to be opened and removed rear-wardly on a supporting carriage (8), as shown. The carriage is advanced when the inductor is to be closed around metal being cast (A) from a continuous casting mold (1).
    Type: Grant
    Filed: April 12, 1988
    Date of Patent: May 30, 1989
    Assignee: Alsthom
    Inventors: Marie C. Nove, Michel Kouyoumdjian
  • Patent number: 4749025
    Abstract: Continuous casting line (10) comprising ingot mould means (11) having any required inclination ranging from 0.degree. to 90.degree., oscillation means (17) and a roller conveyor (12) with at least one curved segment, and which includes at least one electromagnetic source (25) that acts with a variable effect.
    Type: Grant
    Filed: March 6, 1988
    Date of Patent: June 7, 1988
    Assignee: Danieli & C. Officine Meccaniche SpA
    Inventor: Geremia Nonini
  • Patent number: 4732208
    Abstract: In horizontal continuous casting, the casting proceeds step-by-step with the forming strand being intermittently pulled from the mold. The strand forms with a skin with a melt inside of the skin and this melt is stirred by a magnetic stirrer on the outside of the mold. This forms a thin wall in the skin at that location, forming a breaking location or point where the skin pulls apart each time the strand is pulled forwardly. The mold is continuously fed with melt and the skin's strand reforms or welds together at the strand break.
    Type: Grant
    Filed: November 18, 1986
    Date of Patent: March 22, 1988
    Assignee: ASEA AB
    Inventor: Hans-Gunnar Larsson
  • Patent number: 4729422
    Abstract: The process and apparatus according to the invention concern continuous casting of hollow bodies of metals such as aluminum, copper, steels of all types, or other metals or alloys. The process comprises introducing the liquid metal into an annular space between an outer mold and an inner mandrel, the liquid metal being subjected in the vicinity of the mandrel to the action of a movable magnetic field which entrains it in an upward direction. The magnetic field is preferably generated by a magnetic rotor which is disposed in the mandrel. The process is used in particular for producing blanks intended for the production of non-welded pipes and tubes.
    Type: Grant
    Filed: November 8, 1985
    Date of Patent: March 8, 1988
    Assignee: Vallourec
    Inventors: Roland Ernst, Marcel Garnier, Michel Giroutru, Andre Gueussier, Rene Moreau, Pierre Peytavin
  • Patent number: 4709746
    Abstract: A process and apparatus is described for slurry casting an ingot having a non-dendritic structure across substantially its entire cross section. The casting mold has a first chamber for extracting heat from the molten material. The amount of heat extracted from the molten material and the cooling rate of the molten material is controlled to initiate growth of primary phase particles and to form a semi-solid slurry having a desired fraction solid. The mold also has a second chamber for casting the slurry into an ingot. Adjacent the exit portion of the first chamber and the inlet portion of the second chamber, a transition member is provided for delivering the slurry to the casting chamber and for preventing the ingot shell from extending back into the first chamber.
    Type: Grant
    Filed: April 23, 1986
    Date of Patent: December 1, 1987
    Assignee: Alumax, Inc.
    Inventors: Kenneth P. Young, Derek E. Tyler, Harvey P. Cheskis, W. Gary Watson
  • Patent number: 4699205
    Abstract: A method of establishing a turbulent motion of molten steel within a strand guide of a continuous casting plant for casting a steel strand, wherein at least one group of three electromagnetic induction coils are arranged adjacent the strand guide, two of the induction elements being arranged consecutively in the longitudinal direction of the guide. At least two of the induction elements are offset relative to each other, transverse to the longitudinal direction of the strand guide, and the three induction elements form the corner points of an imaginary triangle having no more than one side lying in a plane extending parallel or perpendicular to the longitudinal direction of the strand guide. The imaginary triangle extends across the width of the strand. One phase of a three phase AC current is connected to each electromagnetic induction element. One of the induction elements has its input terminals electrically reversed with respect to the other two elements.
    Type: Grant
    Filed: October 14, 1986
    Date of Patent: October 13, 1987
    Assignee: Voest-Alpine Aktiengesellschaft
    Inventors: Luzian Pochmarski, Wolfgang Polanschutz
  • Patent number: 4671335
    Abstract: A method for the continuous production of cast steel strands which are 200 mm.times.200 mm or less in cross-section by a continuous casting process in which molten steel containing over 0.20% of carbon is fed into a casting mold with a lubricant through a submerged nozzle or in an open stream and continuously drawn out downwardly of the casting mold, which includes the steps of (a) electromagetically stirring the molten steel at a position within said casting mold by the application of a magnetic field induced by introducing into an electromagnetic coil an alternating current of a frequency (f) in the range of 1.5 to 15 and maintaining the magnetic flux density (gauss) in the range of 602 e.sup.-0.10f to 1844 e.sup.-0.
    Type: Grant
    Filed: August 25, 1986
    Date of Patent: June 9, 1987
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Kenzo Ayata, Kiichi Narita, Takasuke Mori, Takahiko Fujimoto
  • Patent number: 4649985
    Abstract: Electromagnetically stirring a molten metal in a continuously casting mold, wherein a plurality of linear motor type stirrer units each having a square shape each side of which is smaller than the height dimension of the mold are arranged in parallel along the long sides of the mold in such a manner that they are adapted to change the attached posture by 90.degree., so as changing the direction of a stirring flow of the molten steel into a given direction. As a result the surface defect is removed and the quality of the solidification structure is improved, and the application range of the kinds of the steels to be cast can be enlarged.
    Type: Grant
    Filed: December 12, 1984
    Date of Patent: March 17, 1987
    Assignee: Kawasaki Steel Corporation
    Inventors: Hisakazu Mizota, Shinji Kojima, Masanori Kodama, Yasuharu Miyazaki
  • Patent number: 4637453
    Abstract: A method for the continuous production of cast steel strands which are 200 mm.times.200 mm or less in cross-section by a continuous casting process in which molten steel containing 0.20% or less of carbon is fed into a casting mold with a lubricant through a submerged nozzle or in an open stream and continuously drawn out downwardly of the casting mold. The method includes the steps of (a) electromagnetically stirring the molten steel at a position within said casting mold by the application of a magnetic field induced by introducing into an electromagnetic coil an alternating current of a frequency (f) in the range of 1.5 to 15 hertz and maintaining the magnetic flux density (Gaub) in the range of 602e.sup.-0.10f to 2441e.sup.-0.
    Type: Grant
    Filed: August 21, 1984
    Date of Patent: January 20, 1987
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Kenzo Ayata, Kiichi Narita, Takasuke Mori, Takahiko Fujimoto
  • Patent number: 4614225
    Abstract: The process and the device according to the invention relate to the continuous casting of hollow bodies made of metals such as aluminum, copper, steels of all types or other metals or alloys. The process involves introducing the liquid metal into an annular space between an external mold and an internal mandrel, the liquid metal being subjected in the vicinity of the mandrel to the action of a moving magnetic field which drives it upward. This field is created by a magnetic rotor housed in the mandrel comprising a rotating part around which is arranged at least one spiral made of magnetized magnetic material made integral with the rotor by at least one collar. The process is applied, in particular, to the production of blanks intended for the manufacture of seamless tubes.
    Type: Grant
    Filed: December 6, 1983
    Date of Patent: September 30, 1986
    Assignee: Vallourec
    Inventors: Roland Ernst, Marcel Garnier, Michel Giroutru, Rene Moreau
  • Patent number: 4590989
    Abstract: An electromagnetic stirrer of linear induction motor type for a continuous casting machine, whose coils are arranged to differ a distance between poles of theeven function components of the travelling wave current distribution with respect to the center thereof from that of the odd function components so that a larger electromagnetic force is generated, thereby eliminating the internal defects, such as macro-segregation or center porosity, and improving quality of the ingot. Also, the electromagnetic stirrer, even when attached to a small-sized mold or a mold of small aspect ratio, demonstrates the sufficient effect.
    Type: Grant
    Filed: August 9, 1984
    Date of Patent: May 27, 1986
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventor: Sumio Kobayashi
  • Patent number: 4577676
    Abstract: A method and apparatus for casting an ingot with refined grain structure from a metallic melt supplied to a casting mold. The mold is intermittently cooled to form a zone of fine dendrites on the inner peripheral surface of the mold. Then, the fine dendrites are reheated to detach secondary dendritic arms therefrom. Finally, the detached secondary dendrite arms are mixed into the melt to serve as nuclei for grain refinement as the melt solidifies into a cast ingot having a refined grain structure.
    Type: Grant
    Filed: December 17, 1984
    Date of Patent: March 25, 1986
    Assignee: Olin Corporation
    Inventor: William G. Watson
  • Patent number: 4573515
    Abstract: A method for electromagnetically stirring molten steel in continuous casting wherein in producing cast slabs or blooms, an electromagnetic stirring force is applied to the unsolidified molten steel in the cast slab or bloom being drawn. An electromagnetic stirrer is installed between drawing positions where the unsolidified thickness is 45% and 15%, respectively, of the thickness as viewed in the direction of the thickness of the cast slab or bloom, and stirring in the casting direction is applied to the unsolidified molten steel in such a manner that the product of the magnetic flux density (gauss) at the interface between the unsolidified and solidified portions and the stirring time in minutes (which is defined as the ratio of the stirring effective length (mm) of the electromagnetic stirrer to the casting speed (m/min)) is 1,600 gauss-min or more per m.sup.3 of the total volume (m.sup.
    Type: Grant
    Filed: March 15, 1983
    Date of Patent: March 4, 1986
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Minoru Kitamura, Kenta Yoshii, Shozo Kawasaki, Katsuyoshi Matsuo, Mitsuo Tomonaga
  • Patent number: 4567937
    Abstract: A method and a device for electromagnetic stirring in a double casting type continuous steel casting apparatus using a pair of linear motor type electromagnetic stirring units opposing to each other, which are arranged in front and in rear of a plurality of cast steel pieces in such a way as to straddle them. The magnetic poles of these stirring units are caused either to move in the same direction in a reciprocal motion, for example, from the left to the right and vice versa or to circulate in the same direction from one of the opposed unit to the other.
    Type: Grant
    Filed: August 27, 1984
    Date of Patent: February 4, 1986
    Assignee: Nippon Steel Corporation
    Inventors: Yoshitaro Ujiie, Hirobumi Maede, Mitsugi Okazaki, Yoshimitsu Kashiwakura
  • Patent number: 4565241
    Abstract: A process for preparing a slurry structured metal composition comprising degenerate dendritic solid particles contained within a lower melting matrix composition, the process comprising vigorously agitating at a given shear rate molten metal as it is solidified. Greatly improved processing efficiencies result if the shear and solidification rates are adjusted so that the ratio of the shear rate to the solidification rate is maintained at a value ranging from 2.times.10.sup.3 to 8.times.10.sup.3.
    Type: Grant
    Filed: June 1, 1982
    Date of Patent: January 21, 1986
    Assignee: International Telephone and Telegraph Corporation
    Inventor: Kenneth P. Young
  • Patent number: 4565238
    Abstract: The present invention relates to a technique or method for stirring molten steel, wherein molten steel charged in a mold for continuous casting is circulated in a smooth flow in order to promote the degassing of the steel as well as to prevent the formation of surface defects on the cast steel. In order to carry out such desirable stirring, the present invention provides for a plurality of electromagnetic stirrers (capable of applying different magnetic field intensities) to be arranged along both long side walls of the casting mold so that the circulating flow of the molten steel can be accelerated or decelerated (depending upon its position) to form a smooth flow.
    Type: Grant
    Filed: August 4, 1983
    Date of Patent: January 21, 1986
    Assignees: Kawasaki Steel Corporation, ASEA AB
    Inventors: Shinji Kojima, Hisakazu Mizota, Masanori Kodama, Yasuharu Miyazaki
  • Patent number: 4562881
    Abstract: A method for stirring the unsolidified metal in the cast strand in continuous casting uses an asymmetrical multiphase stirring current with asymmetry caused by the phase angle of one phase of the current deviating from the phase angle of another phase of the current. In addition to the asymmetrical stirring, symmetrical stirring can be used at a location adjacent to the asymmetrical stirring so that the benefits of both types of stirring are obtained.
    Type: Grant
    Filed: October 18, 1982
    Date of Patent: January 7, 1986
    Assignee: ASEA Aktiebolag
    Inventor: Sten Kollberg
  • Patent number: 4562879
    Abstract: In a continuous-casting method molten steel is continuously introduced into a continuous-casting mold to form therein a strand having a free surface in the mold, a pair of relatively wide faces, and a pair of relatively narrow faces. The mold and the steel therein are continuously cooled to externally solidify the molten-steel strand while leaving same internally molten and the externally solid and internally molten strand is continuously withdrawn from the lower end of the mold. The core of the strand solidifies increasingly as it moves from the mold and terminates downstream of the mold at a pool bottom. At each of a plurality of locations spaced apart about 1 m to 2 m longitudinally along the strand between the mold and the pool bottom a respective magnetic field is formed with the fields passing through the strand from between about 3 m to 7 m beneath the free surface to about 2 m to 6 m from the pool bottom.
    Type: Grant
    Filed: June 17, 1983
    Date of Patent: January 7, 1986
    Assignee: Institut de Recherches de la Siderurgie Francaise
    Inventors: Jean-Pierre Birat, Patrick Neu, Denis Senaneuch
  • Patent number: 4544019
    Abstract: This invention is in a method of manufacturing a composite steel ingot wherein a consumable electrode is inserted into an empty space positioned concentrically with said steel ingot, and electric power is fed to said consumable electrode to effect electroslag remelting under a slag bath and then to solidify the molten metal, while taking out an electric current through a plurality of collecting electrodes which are electrically connected to said steel ingot placed on a surface plate, the improvement in that a flow path of the electric current passing from said consumable electrode to said collecting electrodes is moved in the circumferential direction of said steel ingot during said electroslag remelting.
    Type: Grant
    Filed: May 11, 1983
    Date of Patent: October 1, 1985
    Assignee: Hitachi, Ltd.
    Inventors: Hideyo Kodama, Yasuo Kondo, Kimihiko Akahori
  • Patent number: 4541472
    Abstract: A system for stirring in continuous casting is formed by an inductive stirrer which inductively stirs molten metal in a continuously cast strand and at least one set of two water-cooling pipes positioned in front of the stirrer and having nozzles which eject water cooling-sprays against the strand. The two pipes have ends extending beyond the field and between their ends are electrically isolated from each other and the stirrer. By electrically interconnecting these ends outside of the field, the two pipes form a closed electric loop in which currents induced by the stirrers field cancel so that the net current flow is zero and the stirrer's field is not shielded from the strand.
    Type: Grant
    Filed: September 7, 1983
    Date of Patent: September 17, 1985
    Assignee: ASEA Aktiebolag
    Inventors: Jan Erik Eriksson, Mats Karlsson, Sten Kollberg, Bengt Mansson
  • Patent number: 4529030
    Abstract: A horizontal continuous casting process wherein at least two electromagnetic stirring devices of a rotary magnetic field type are arranged in series direction whereby electromagnetic stirring force acts on non-solidified molten metal, and the distance between the electromagnetic stirring devices of first and second stages is set to specified relation.
    Type: Grant
    Filed: January 20, 1984
    Date of Patent: July 16, 1985
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Takasuke Mori, Kenzo Ayata, Jun Miyazaki, Takahiko Fujimoto, Hitoshi Nakata
  • Patent number: 4527615
    Abstract: An electromagnetic within-mold stirring method and apparatus wherein electromagnetic stirring is imparted to molten steel passing through a mold, under the following conditions where the maximum flux density (in gauss) of a magnetic field induced by an electro-magnetic coil ranges from 1045.e.sup.-0.16f to 2054.e.sup.-0.12f (f: frequency, 1-15 Hz) and the place of the maximum magnetic flux density is within the range of 350 mm from the junction between the pouring nozzle and the mold in the direction of drawing of the cast-piece.
    Type: Grant
    Filed: February 25, 1983
    Date of Patent: July 9, 1985
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Kiichi Narita, Takasuke Mori, Kenzo Ayata, Jun Miyazaki, Takahiko Fujimoto, Hitoshi Nakata
  • Patent number: 4524819
    Abstract: A leaded, free-cutting steel is manufactured by a continuous casting process without causing any pollution of the environment or manufacturing apparatus by toxic gases or fumes and in a high yield of lead addition with a high quality, wherein lead, lead alloy, or a composite lead feed material comprising lead or lead alloy covered with a metallic material harmless for the steel such as, for example, aluminum or iron, is directly added to molten steel which is being electromagnetically stirred in the horizontal direction in a mold.
    Type: Grant
    Filed: December 13, 1983
    Date of Patent: June 25, 1985
    Assignee: Mitsubishi Steel Mfg. Co., Ltd.
    Inventor: Tsuneo Yoshimura
  • Patent number: 4523628
    Abstract: A process for casting metals comprising simultaneously applying a stationary magnetic field and a variable magnetic field to the molten metal in the course of solidification. The magnetic fields act in the same direction and generate radial vibrations in the metal, causing the cast metal to have an improved homogeneous structure and surface condition.
    Type: Grant
    Filed: July 7, 1983
    Date of Patent: June 18, 1985
    Assignee: Aluminium Pechiney
    Inventor: Charles Vives
  • Patent number: 4518027
    Abstract: A mold for continuous casting of a magnetic metal includes a thin copper mold wall, a backup piece formed of a non-magnetic material serving to support the thin copper mold wall, passageways for a cooling medium between the thin copper mold wall and the backup piece, a clamping piece for clamping the backup piece against the thin copper mold wall, and an electromagnetic stirrer coil located between the backup piece and the clamping piece.
    Type: Grant
    Filed: February 6, 1984
    Date of Patent: May 21, 1985
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventor: Futoshi Kamei