EP0088701B1 - Procédé et installation de coulée d'un métal non ferreux à l'état liquide - Google Patents

Procédé et installation de coulée d'un métal non ferreux à l'état liquide Download PDF

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Publication number
EP0088701B1
EP0088701B1 EP83400479A EP83400479A EP0088701B1 EP 0088701 B1 EP0088701 B1 EP 0088701B1 EP 83400479 A EP83400479 A EP 83400479A EP 83400479 A EP83400479 A EP 83400479A EP 0088701 B1 EP0088701 B1 EP 0088701B1
Authority
EP
European Patent Office
Prior art keywords
casting
metal
inert gas
insulation
jet
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP83400479A
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German (de)
English (en)
French (fr)
Other versions
EP0088701A1 (fr
Inventor
Jean Francis Rimbert
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.)
Noranda Inc
Original Assignee
Noranda Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Noranda Inc filed Critical Noranda Inc
Publication of EP0088701A1 publication Critical patent/EP0088701A1/fr
Application granted granted Critical
Publication of EP0088701B1 publication Critical patent/EP0088701B1/fr
Expired legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D5/00—Machines or plants for pig or like casting
    • B22D5/04—Machines or plants for pig or like casting with endless casting conveyors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D1/00—Treatment of fused masses in the ladle or the supply runners before casting
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/003—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting by using inert gases

Definitions

  • the subject of the invention is a method and an installation for casting in the form of a free jet of a non-ferrous metal capable of presenting the problem of the formation of a solid metal foam at the foot of the casting jet. It applies more particularly to the casting of zinc in an ingot mold.
  • This problem of the protection of the casting jet arises in a particular way during the casting of non-ferrous metals capable of causing the formation of a solid metallic foam at the foot of the casting jet, and more especially during the casting of zinc in an ingot mold.
  • the subject of the present invention is a method of casting a non-ferrous metal in the liquid state, which makes it possible to avoid the formation of solid metallic foam, in falling casting installations of the usual type.
  • the invention provides a casting method in the form of a free jet of a non-ferrous metal, which presents the problem of the formation of a solid metallic foam at the foot of the casting jet, of a reserve of said metal.
  • liquid to at least one receptacle for said metal in which at least one of the receptacles is covered by isolation means so as to form a zone of isolation from the environment, and said zone is previously inerted isolation by means of supply and distribution of an inert gas inside said isolation zone, the oxygen content therein being less than 1% preferably 0.1%, characterized in that the 'a direct passage of the liquid metal is established between said reserve and the receiving container placed below the pouring jet, so that the pouring jet of the liquid metal remains entirely inside the isolation zone, while maintaining the injection of inert gas in the upper part of said isolation zone at a rate such that the atmosphere in the vicinity of the jet of liquid metal has an oxygen content lower than the above values.
  • the receiving container is preferably an ingot mold, the reserve of liquid metal preferably a distributor tray with pouring orifice at its bottom.
  • the isolation means can consist of metal covers or metal walls, possibly connected by connecting means.
  • a set of ingot molds is made to pass, arranged transversely side by side, under said reserve of liquid metal, and each of the ingot molds is inerted beforehand before passing under the jet of liquid metal.
  • at least two adjacent molds of said set are covered by the isolation wall.
  • the invention also relates to a casting installation in the form of a free jet of a non-ferrous metal which presents the problem of the formation of a solid metal foam at the foot of the casting jet, of a reserve of said liquid metal to at least one receptacle for receiving said metal, comprising isolation means covering at least one of the receptacles so as to form a zone of isolation from the environment and means for supplying and distributing a gas inert inside said isolation zone, the oxygen content therein being less than 1%, preferably less than 0.1%, characterized in that it comprises means allowing the direct passage of the liquid metal between said reserve and the receiving container placed below the pouring jet inside the isolation zone, and in that the inert gas supply and distribution means maintain the injection of inert gas in the upper part of said zone isolation at a flow rate such that the atmosphere in the vicinity of the metal jet itself has an oxygen content lower than the above values.
  • the creation of the isolation zone with respect to the atmosphere and the introduction into this zone of a liquefied inert gas prevents any oxidation of the liquid metal, and therefore the formation of solid metallic foam. Indeed, there is no stabilization or solidification of the bubbles formed which therefore remain liquid and are eliminated in the metal bath. Thus, thanks to the process of the invention, any loss of metal is avoided during casting and ingots free of foam are obtained at the end of the process.
  • a zinc casting installation comprises a metal distributor tray 1 in the shape of a rectangular parallelepiped, having a bottom 2 and four side walls 3a, 3b and 4a, 4b.
  • the bottom 2 of the tank 1 has a slot 5.
  • a chute 6 for supplying liquid zinc connected to a holding furnace (not shown in the figure) and slightly inclined, opens at the upper part of the wall 3a of the distribution tank 1.
  • Metal ingot molds L placed transversely side by side and integral with two endless transmission chains 8 via pivot axes 16, travel in the direction of arrow F under the distribution bin 1 and successively take positions 7A , 7B, 7C, 7D.
  • These ingot molds L are in the form of a trough comprising a rectangular bottom 9 and four side walls 10a, 10b and 11a, 11b slightly inclined.
  • a metal cover 12 in the shape of a rectangular parallelepiped has a horizontal upper plate 13 and four vertical side walls 14a, 14b and 15a, 15b.
  • the upper plate 13 is pierced with a rectangular opening having the dimensions just necessary to embed the lower part of the distribution tank 1.
  • the plate 13 of the cover 12 is fixed by means of four metal connection plates 18 using of bolts 19 to the walls 3a, 3b and 4a, 4b of the distribution box 1.
  • the cover 12 completely overhangs the two ingot molds 7B and 7C, and its side walls 14a, 14b and 15a, 15b arrive just flush with the upper edges of these ingot molds. More specifically, the lower edge 20 of the walls 14a, 14b stops just above the upper edges 21 of the walls 10a, 10b of the molds 7B and 7C and the lower edge 22 of the walls 15a, 15b stops just at the above the upper edges 28 of the walls 11a, 11b of the molds 7B and 7C.
  • the cover 12 forms a quasi-hermetic protective cover for the internal cavity of the molds 7B and 7C while not preventing them from scrolling.
  • a ramp 23 for supplying and distributing a liquefied inert gas is fixed under the upper plate 13 parallel to the wall 14a, in the upstream part of the cover 12 relative to the direction of movement F of the molds L.
  • This ramp 23 is of the conventional phase separator type, comprising a degassing slot 29 at its upper part and provided, at its lower part and at regular intervals, with injection nozzles 24 for liquid inert gas oriented downwards.
  • the ramp 23 is connected to a tank of liquefied inert gas 25 via a conduit 26 and a dip tube 27.
  • the supply and distribution ramp 23 is preferably located in the upstream part of the cover 12 relative to the direction of movement F, as shown in the figures, but it can also be placed in the downstream part of the cover 12; there may also be two supply and distribution ramps for liquefied inert gas, one in the upstream part and the other in the downstream part of the cover.
  • a vertical conduit 30 crosses the downstream part of the upper plate 13 relative to the direction of movement F and opens slightly below said plate 13.
  • This conduit 30, fitted with a pump 32, is connected to an oxygen analyzer 31.
  • a preheating ramp 33 arranged parallel to the wall 14a of the cover 12 and above the ingot mold 7A, is fixed to the wall 14a by means of metal rods 34 provided with metal rings 35.
  • This preheating ramp 33 is consisting of a pipe 36 connected to fuel gas and oxidizing gas supply sources (not shown in the figures) and provided, at regular intervals, with burners 37 oriented towards the internal cavity of the mold 7A.
  • the distribution tank 1 contains a bath of liquid zinc 40 which flows through the slot 5 in the form of a jet J to form a bath of liquid zinc 41 in the mold 7C.
  • the operation of the installation according to the invention is as follows.
  • the distributor tank 1 is continuously supplied with liquid zinc, coming from a holding oven, using the chute 6; the impurities, in particular the oxides formed during transport in air in the chute 6, remain on the surface of the bath of liquid metal 40 thus formed in the distributor 1 and the pure liquid zinc settles at the bottom of the distributor 1 and flows by the slot 5 in the mold which is in position 7C.
  • each mold L in position 7A, is preheated to a temperature above 100 ° C by means of the preheating ramp 33.
  • this ingot mold L arrives in position 7B, it receives the jets of a liquefied inert gas, such as argon or nitrogen, injected by the nozzles 24 of the supply rail 23.
  • a liquefied inert gas such as argon or nitrogen
  • the oxygen content of the atmosphere in the vicinity of the pouring jet J and of the surface of the metal bath 41 is continuously monitored using the oxygen analyzer 31, and the injection rate of the liquefied inert gas into the supply rail 23 so that this oxygen content is less than 1%, preferably 0.1%.
  • each mold in position 7A is intended, in certain cases, to avoid excessive cooling of the latter when it is in position 7B as well as of the bath of liquid metal which it will contain when it is in position 7C, cooling which comes from the frigories brought by liquefied inert gas.
  • a zinc casting installation comprises a distribution tank 50 in the form of a rectangular parallelepiped comprising a bottom 51 and four side walls 52.
  • the bottom 51 of the tank 50 has a slot 53.
  • a chute 54 d the liquid zinc inlet opens into the upper part of the distribution tank 50.
  • Metal ingot molds 53 placed transversely side by side, pass in the direction of arrow G, following a slightly ascending slope by means of a transport ramp (not shown in the figures), and successively assume positions 55A, 55B, 55C , 55D.
  • These ingot molds 55 are in the shape of a trough comprising a rectangular bottom 56 and four side walls 57 slightly inclined.
  • a metal cover 59 bearing on the protection plates of the transport ramp (not shown in the figures) and overhanging at least one ingot mold 55 is equipped with a ramp 60 for supplying inert gas.
  • This ramp 60 is, on the other hand, connected to a wall 52 of a distribution tank 50 by a skirt 61, made of refractory fabric for example.
  • An injection pipe for a liquefied inert gas 62 opens out above the internal cavity of one of the ingot molds 55.
  • a skirt 63 fixed to the bottom 51 of the distributor 50, descends vertically into the internal cavity of the ingot mold next.
  • a metal cover 64 bearing on three of the side walls 52 of the tank 1 is equipped with a ramp 65 for supplying inert gas.
  • a skirt 67 connects the ramp 65 to a metal cover 68 which overhangs the chute 54.
  • a vertical partition 58 which stops at a distance from the bottom of the chute 54, stops the zinc foam formed on the surface of the liquid zinc during its transport in the open air to the chute and forces the pure zinc to pass through the bottom.
  • a skirt 69 connects a side wall 52 of the tank 50 and the bottom of the chute 54.
  • FIG. 3 represents the respective position of the elements of the installation when filling an ingot mold 55C with liquid zinc
  • FIG. 4 represents the respective position of the elements of the installation during the passage from an ingot mold filled with liquid zinc 55C to the next empty ingot mold 55B.
  • the distributor 50 When filling the mold 55C (fig. 3), the distributor 50 is in a horizontal position. It is supplied with liquid zinc by the chute 54; thanks to the protection zone constituted by the cover 68, the skirt 67 and the cover 64, and the inerting of said protection zone by an inert gas (ramp 65) the surface of the bath of liquid zinc 70 contained in the chute 54 , the jet of liquid zinc 71 flowing from the chute 54 into the tank 50 and the surface of the bath of liquid zinc 72 contained in the tank 50, are perfectly clean, that is to say free from dross and foam due to possible oxidation of zinc.
  • the jet of liquid zinc 73 and the surface of the bath of liquid zinc 74 contained in the mold 55C are protected against any oxidation by virtue of the confinement zone constituted by the cover 59, the bottom 51 and the inerting from said containment zone by an inert gas (ramp 60) and a liquefied inert gas (cane 62).
  • the set of molds is scrolled so as to bring the following mold 55B under the distribution tray 50.
  • the tray 50 is placed in the tilted position by tilting about an axis 66 so that the level of the liquid zinc bath 72 is such that the zinc cannot flow through the slot 53.
  • the inerting of the protection zone (hood 68, skirt 67 and hood 64) and of the confinement zone (hood 59, bottom 51 is maintained) and skirt 63), as described above.
  • the confinement zone overhanging at least one ingot mold is inert, whether in the filling position of one ingot mold or in the position for passing from one ingot mold to another, both by injection of an inert gas liquefied upstream, relative to the direction of movement G, of the casting slot 53 and injection of an inert gas downstream of said slot 53; in this case, the amount of liquefied inert gas. injected is 75% to 100% of the total amount of gas used.
  • the confinement zone is inerted by injection of an inert liquefied gas only upstream of the casting slot 53.
  • the confinement zone is inerted by injection of a gas inert liquefied both upstream and downstream of the casting slot 53.
  • the inert gas used can be, for example, nitrogen or argon.
  • the invention applies more particularly to the continuous casting of zinc in an ingot mold, but it could also be applied to the casting of any non-ferrous metal in free fall liable to present the problem of the formation of solid metallic foam at the foot of the casting jet, such as lead or lead and calcium alloys, or zinc alloys.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Manufacture And Refinement Of Metals (AREA)
EP83400479A 1982-03-08 1983-03-08 Procédé et installation de coulée d'un métal non ferreux à l'état liquide Expired EP0088701B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8203817A FR2523005A1 (fr) 1982-03-08 1982-03-08 Procede et installation de coulee d'un metal non ferreux en lingotiere
FR8203817 1982-03-08

Publications (2)

Publication Number Publication Date
EP0088701A1 EP0088701A1 (fr) 1983-09-14
EP0088701B1 true EP0088701B1 (fr) 1986-12-10

Family

ID=9271721

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83400479A Expired EP0088701B1 (fr) 1982-03-08 1983-03-08 Procédé et installation de coulée d'un métal non ferreux à l'état liquide

Country Status (11)

Country Link
US (1) US4565234A (xx)
EP (1) EP0088701B1 (xx)
JP (1) JPS58167056A (xx)
AU (1) AU555738B2 (xx)
BE (1) BE896099A (xx)
CA (1) CA1257067A (xx)
DE (1) DE3368215D1 (xx)
ES (1) ES8404216A1 (xx)
FR (1) FR2523005A1 (xx)
IT (1) IT1161582B (xx)
ZA (1) ZA831233B (xx)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4549598A (en) * 1981-12-17 1985-10-29 Noranda Inc. Process for minimizing foam formation during free falling of molten metal into moulds, launders or other containers
AU560253B2 (en) * 1983-12-23 1987-04-02 Noranda Mines Ltd. Process and apparatus for minimizing foam formation during free falling of molten metal into moulds, launders or other containers
US4576220A (en) * 1983-12-23 1986-03-18 Noranda Inc. Method and apparatus for maintaining an atmosphere around a predetermined portion of an endless discrete object conveyor
JPS61158025A (ja) * 1984-12-28 1986-07-17 Canon Inc 磁気記録媒体
FR2607039B1 (fr) * 1986-11-26 1989-03-31 Air Liquide Procede de coulee d'acier comportant un inertage du bain d'acier par de l'anhydride carbonique sous forme de neige
US4933005A (en) * 1989-08-21 1990-06-12 Mulcahy Joseph A Magnetic control of molten metal systems
US5404929A (en) * 1993-05-18 1995-04-11 Liquid Air Corporation Casting of high oxygen-affinity metals and their alloys
AU723278B2 (en) * 1995-12-14 2000-08-24 Australian Magnesium Operations Pty Ltd Ingot mould system
AUPN716195A0 (en) * 1995-12-14 1996-01-18 Australian Magnesium Corporation Pty Ltd Ingot mould system
FR2809643B1 (fr) * 2000-05-31 2002-10-25 Brochot Sa Procede et dispositif pour proteger un metal fondu non ferreux
KR20030085642A (ko) * 2002-04-29 2003-11-07 김학배 비철금속판재의 주조방법
US20080184848A1 (en) 2006-08-23 2008-08-07 La Sorda Terence D Vapor-Reinforced Expanding Volume of Gas to Minimize the Contamination of Products Treated in a Melting Furnace
US20090064821A1 (en) * 2006-08-23 2009-03-12 Air Liquide Industrial U.S. Lp Vapor-Reinforced Expanding Volume of Gas to Minimize the Contamination of Products Treated in a Melting Furnace
US8403187B2 (en) * 2006-09-27 2013-03-26 Air Liquide Industrial U.S. Lp Production of an inert blanket in a furnace

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1978222A (en) * 1932-09-24 1934-10-23 Allegheny Steel Co Method of and apparatus for treating metallic materials
FR1262890A (fr) * 1960-07-12 1961-06-05 Procédé et dispositif de coulée et d'empilage de pièces métalliques, en particulier de plaques
GB956865A (en) * 1959-07-15 1964-04-29 Heinrich Josef Baggeler Improvements in or relating to methods and apparatus for casting and stacking metal pieces
FR1319216A (fr) * 1962-04-06 1963-02-22 Verwaltungs Ges Moeller & Neum Installation de coulée pour métaux, notamment pour brames de zinc
JPS4830627A (xx) * 1971-08-26 1973-04-23
BE793567A (fr) * 1971-12-30 1973-06-29 Air Liquide Procede de coulee de metal
US3991813A (en) * 1973-08-23 1976-11-16 Allmanna Svenska Elektriska Aktiebolaget Melt casting apparatus
JPS5332829A (en) * 1976-09-09 1978-03-28 Tokyo Shibaura Electric Co Continuous casting device
JPS53137830A (en) * 1977-05-09 1978-12-01 Nippon Chiyuutankou Kk Degassing casting method and apparatus for molten steel
FR2403849A1 (fr) * 1977-09-23 1979-04-20 Siderurgie Fse Inst Rech Nouveau procede de coulee continue centrifuge electromagnetique des metaux en fusion
JPS626804Y2 (xx) * 1980-05-29 1987-02-17

Also Published As

Publication number Publication date
IT1161582B (it) 1987-03-18
JPS58167056A (ja) 1983-10-03
IT8319809A0 (it) 1983-02-25
ES520367A0 (es) 1984-04-16
BE896099A (fr) 1983-09-07
EP0088701A1 (fr) 1983-09-14
US4565234A (en) 1986-01-21
CA1257067A (fr) 1989-07-11
ES8404216A1 (es) 1984-04-16
ZA831233B (en) 1983-11-30
FR2523005A1 (fr) 1983-09-16
AU555738B2 (en) 1986-10-09
FR2523005B1 (xx) 1984-12-07
AU1186383A (en) 1983-09-15
DE3368215D1 (en) 1987-01-22

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