EP0050578A1 - Vorrichtung zum Behandeln eines geschmolzenen Metallbades durch Gaseinblasen - Google Patents

Vorrichtung zum Behandeln eines geschmolzenen Metallbades durch Gaseinblasen Download PDF

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Publication number
EP0050578A1
EP0050578A1 EP81420150A EP81420150A EP0050578A1 EP 0050578 A1 EP0050578 A1 EP 0050578A1 EP 81420150 A EP81420150 A EP 81420150A EP 81420150 A EP81420150 A EP 81420150A EP 0050578 A1 EP0050578 A1 EP 0050578A1
Authority
EP
European Patent Office
Prior art keywords
liquid metal
treating
plug
metal bath
agitator
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.)
Granted
Application number
EP81420150A
Other languages
English (en)
French (fr)
Other versions
EP0050578B1 (de
Inventor
François Bucourt
Henri Fetaud
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.)
Rio Tinto France SAS
Original Assignee
Aluminium Pechiney SA
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 Aluminium Pechiney SA filed Critical Aluminium Pechiney SA
Publication of EP0050578A1 publication Critical patent/EP0050578A1/de
Application granted granted Critical
Publication of EP0050578B1 publication Critical patent/EP0050578B1/de
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/09—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting by using pressure
    • B22D27/13—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting by using pressure making use of gas pressure
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B21/00—Obtaining aluminium
    • C22B21/06—Obtaining aluminium refining
    • C22B21/064—Obtaining aluminium refining using inert or reactive gases
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B21/00—Obtaining aluminium
    • C22B21/06—Obtaining aluminium refining
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
    • C22B9/05—Refining by treating with gases, e.g. gas flushing also refining by means of a material generating gas in situ

Definitions

  • the present invention relates to a device for treating a bath of liquid metal and, in particular, of aluminum or its alloys by gas injection.
  • the first consists in passing the liquid metal through inert or active filtration media which retain impurities either mechanically, or following chemical reactions, or by exerting the two effects;
  • the second way resorts to the use of inert or reactive gases or their mixtures, which are more or less intensely stirred with the liquid metal, in the presence or not of products such as fluxes.
  • gases are injected in the form of small discrete bubbles by means of a device consisting of a rotary shaft secured to a finned rotor, of a fixed sleeve surrounding said shaft and connected at its lower end to a finned stator;
  • shaft and sleeve are separated by an axial passage in which the gases are transported and introduced at the level of the fins where they are subdivided into small bubbles and brought into intimate contact with the metal stirred by the rotor.
  • This device for treating a bath of liquid metal contained in a container by gas injection is characterized in that it comprises a rotary agitator, the lower end of which rests, when stationary, on a gas injection plug. placed at the bottom of the bath and which, under the action of the pressure of the gas emitted by the plug, lifts and, thus supported by a fluid bearing, can, under the effect of an external torque, freely rotate around its axis and let escape by the space which separates it from the cap, a multitude of regularly dispersed gas bubbles.
  • the device according to the invention is therefore formed by the combination of two means: a rotary agitator, on the one hand, and a gas injection plug, on the other hand.
  • the rotary agitator consists of a massive piece of cylindrical-tapered shape, the upper part of which is provided with a cylindrical opening in which engages the shaft on which an external torque is exerted.
  • the lower part of this agitator may have a smooth surface or have several radial notches of increasing depth towards the periphery, so as to facilitate the entrainment of the injection gases.
  • These indentations extend for example in length on a third of the diameter of the agitator and can extend on the lateral face forming kinds of helices facing to the right or to the left and whose pitch is more or less depending on the processing conditions.
  • the agitator shaft is equipped with an antivortex system placed at the bath-atmosphere interface, so as to limit the movements of the liquid metal which could hinder proper dispersion of the gases.
  • the external torque is preferably exerted by a variable speed motor fixed on a support arranged at the top of the container.
  • the shaft of this motor is integral with the shaft of the agitator by means of any connection system which allows the agitator to be able to describe a vertical translational movement over a distance of several millimeters.
  • the gas injection plug consists of a cylindrical piece, the upper face of which is pierced with holes of small diameter, which can be arranged in crowns and which are connected inside the plug to channels grouping into one channel. central which leads to an expansion chamber supplied with gas by a pipe external to the container.
  • the mass of the plug located above the expansion chamber can be produced with a porous material.
  • the agitator and the stopper are arranged, with respect to each other, so that the vertical axes of symmetry of each of them are coincident.
  • the lower face of the agitator and the upper face of the stopper are adapted to one another so that, at rest, they are in contact with one another and cause an obstruction of the injection orifices of gas.
  • This adaptation can be achieved for example by giving said face of the stopper a conical shape and by providing in said face of the stirrer a cavity of similar shape.
  • the gas pressure admitted at the level of the plug raises the agitator and produces a fluid bearing so that, when the drive motor is put into service, said agitator can rotate freely without contact with the cap.
  • the agitator and the stopper are preferably composed of graphite, but any other material having sufficient resistance to liquid metal is also suitable.
  • the gas admitted by the plug is a neutral gas such as argon, nitrogen or a reactive gas such as chlorine or their mixtures, or any other gas capable of treating the metal.
  • a neutral gas such as argon, nitrogen or a reactive gas such as chlorine or their mixtures, or any other gas capable of treating the metal.
  • Such a device is placed on a container containing the metal bath to be treated. It can be, for example, a pocket through which the metal passes continuously before being cast.
  • This container can carry, in a conventional manner, a partition and, then, the device is placed in the upstream compartment.
  • the bottom of this pocket can be provided with a filtration bed or not.
  • This pocket is equipped with means which make it possible to maintain a neutral atmosphere on the surface of the liquid metal and thus avoid any oxidizing action of the outside air.
  • This container can also be provided with heating means intended to maintain the metal in the liquid state.
  • Figure 2 shows the arrangement of the notches (5) on the conical surface (4) of the lower part of the agitator.
  • the pocket is supplied with liquid metal by the channel (25) and flows towards the bottom of the upstream compartment, then below the partition (19) towards the downstream compartment before leaving the pocket by the channel (27).
  • the metal bath delimited by the walls of the pocket and the surface (28) is intimately stirred by the agitator with the formation of a multitude of finely dispersed gas bubbles which escape through the space (29) forming under the gas pressure between the lower part of the agitator and the upper part of the plug.
  • the metal to be treated was an aluminum alloy of the 6000 series, which was brought into the liquid state, at a temperature close to 720 ° C., at a flow rate of 5 tonnes per hour in a ladle where the height bath was 80 cm. :
  • the plug of the channel type, was supplied with argon at a rate of approximately 2 m3 / h at a pressure between 1.2 and 1.4 bar.
  • the agitator was rotating at a speed of 400 rpm.
  • the alloy presented 10 bubbles in the vacuum solidification test; after passing through the pocket, the number of bubbles was zero. This shows the effectiveness of the treatment obtained by means of the claimed device.
  • the present invention finds its application in the treatment of liquid metals with a gas, and in particular in the treatment of aluminum or its alloys for the elimination of hydrogen and non-metallic impurities.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Coating With Molten Metal (AREA)
EP81420150A 1980-10-14 1981-10-13 Vorrichtung zum Behandeln eines geschmolzenen Metallbades durch Gaseinblasen Expired EP0050578B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8022193A FR2491954A1 (fr) 1980-10-14 1980-10-14 Dispositif de traitement d'un bain de metal liquide par injection de gaz
FR8022193 1980-10-14

Publications (2)

Publication Number Publication Date
EP0050578A1 true EP0050578A1 (de) 1982-04-28
EP0050578B1 EP0050578B1 (de) 1984-03-21

Family

ID=9246990

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81420150A Expired EP0050578B1 (de) 1980-10-14 1981-10-13 Vorrichtung zum Behandeln eines geschmolzenen Metallbades durch Gaseinblasen

Country Status (15)

Country Link
US (1) US4372541A (de)
EP (1) EP0050578B1 (de)
JP (1) JPS5792146A (de)
KR (1) KR830007187A (de)
AU (1) AU540945B2 (de)
CA (1) CA1165117A (de)
DE (1) DE3162821D1 (de)
ES (1) ES506075A0 (de)
FR (1) FR2491954A1 (de)
GR (1) GR75823B (de)
IN (1) IN155192B (de)
NO (1) NO813447L (de)
OA (1) OA06917A (de)
RO (1) RO83654B (de)
YU (1) YU243581A (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2562449A1 (fr) * 1984-04-06 1985-10-11 Servimetal Dispositif de traitement de l'acier, avant coulee continue, par injection de gaz
FR2629101A1 (fr) * 1988-03-23 1989-09-29 Radex Heraklin Industriebeteil Brique pour l'introduction de gaz ou de produits de reaction dans un recipient de coulee metallurgique

Families Citing this family (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3564449D1 (en) * 1984-11-29 1988-09-22 Foseco Int Rotary device, apparatus and method for treating molten metal
AU591889B2 (en) * 1985-03-26 1989-12-21 British Steel Plc Improvements in or relating to outlet valves for metal containing vessels
US4673434A (en) * 1985-11-12 1987-06-16 Foseco International Limited Using a rotary device for treating molten metal
AU605949B2 (en) * 1987-12-25 1991-01-24 Nkk Corporation Method for cleaning molten metal and apparatus therefor
DE3907887A1 (de) * 1988-03-23 1989-10-26 Radex Heraklith Spuelstein
US4954167A (en) * 1988-07-22 1990-09-04 Cooper Paul V Dispersing gas into molten metal
US5158737A (en) * 1991-04-29 1992-10-27 Altec Engineering, Inc. Apparatus for refining molten aluminum
US5660614A (en) * 1994-02-04 1997-08-26 Alcan International Limited Gas treatment of molten metals
US5678807A (en) * 1995-06-13 1997-10-21 Cooper; Paul V. Rotary degasser
US5944496A (en) * 1996-12-03 1999-08-31 Cooper; Paul V. Molten metal pump with a flexible coupling and cement-free metal-transfer conduit connection
US5951243A (en) * 1997-07-03 1999-09-14 Cooper; Paul V. Rotor bearing system for molten metal pumps
US6027685A (en) * 1997-10-15 2000-02-22 Cooper; Paul V. Flow-directing device for molten metal pump
US6056803A (en) * 1997-12-24 2000-05-02 Alcan International Limited Injector for gas treatment of molten metals
US6093000A (en) 1998-08-11 2000-07-25 Cooper; Paul V Molten metal pump with monolithic rotor
US6303074B1 (en) 1999-05-14 2001-10-16 Paul V. Cooper Mixed flow rotor for molten metal pumping device
US6689310B1 (en) 2000-05-12 2004-02-10 Paul V. Cooper Molten metal degassing device and impellers therefor
US6723276B1 (en) * 2000-08-28 2004-04-20 Paul V. Cooper Scrap melter and impeller
US20070253807A1 (en) 2006-04-28 2007-11-01 Cooper Paul V Gas-transfer foot
US20050013715A1 (en) * 2003-07-14 2005-01-20 Cooper Paul V. System for releasing gas into molten metal
US7507367B2 (en) * 2002-07-12 2009-03-24 Cooper Paul V Protective coatings for molten metal devices
US7731891B2 (en) * 2002-07-12 2010-06-08 Cooper Paul V Couplings for molten metal devices
US7470392B2 (en) * 2003-07-14 2008-12-30 Cooper Paul V Molten metal pump components
US7402276B2 (en) 2003-07-14 2008-07-22 Cooper Paul V Pump with rotating inlet
US7906068B2 (en) 2003-07-14 2011-03-15 Cooper Paul V Support post system for molten metal pump
JP5099399B2 (ja) * 2005-11-04 2012-12-19 独立行政法人日本原子力研究開発機構 溶湯精錬装置及び溶湯精錬方法
US8366993B2 (en) * 2007-06-21 2013-02-05 Cooper Paul V System and method for degassing molten metal
US9205490B2 (en) 2007-06-21 2015-12-08 Molten Metal Equipment Innovations, Llc Transfer well system and method for making same
US8337746B2 (en) 2007-06-21 2012-12-25 Cooper Paul V Transferring molten metal from one structure to another
US9410744B2 (en) 2010-05-12 2016-08-09 Molten Metal Equipment Innovations, Llc Vessel transfer insert and system
US8613884B2 (en) 2007-06-21 2013-12-24 Paul V. Cooper Launder transfer insert and system
US9409232B2 (en) 2007-06-21 2016-08-09 Molten Metal Equipment Innovations, Llc Molten metal transfer vessel and method of construction
US9156087B2 (en) 2007-06-21 2015-10-13 Molten Metal Equipment Innovations, Llc Molten metal transfer system and rotor
US9643247B2 (en) 2007-06-21 2017-05-09 Molten Metal Equipment Innovations, Llc Molten metal transfer and degassing system
US8524146B2 (en) 2009-08-07 2013-09-03 Paul V. Cooper Rotary degassers and components therefor
US10428821B2 (en) * 2009-08-07 2019-10-01 Molten Metal Equipment Innovations, Llc Quick submergence molten metal pump
US8449814B2 (en) * 2009-08-07 2013-05-28 Paul V. Cooper Systems and methods for melting scrap metal
US8535603B2 (en) 2009-08-07 2013-09-17 Paul V. Cooper Rotary degasser and rotor therefor
US8444911B2 (en) 2009-08-07 2013-05-21 Paul V. Cooper Shaft and post tensioning device
US8714914B2 (en) 2009-09-08 2014-05-06 Paul V. Cooper Molten metal pump filter
US9108244B2 (en) * 2009-09-09 2015-08-18 Paul V. Cooper Immersion heater for molten metal
US9903383B2 (en) 2013-03-13 2018-02-27 Molten Metal Equipment Innovations, Llc Molten metal rotor with hardened top
US9011761B2 (en) 2013-03-14 2015-04-21 Paul V. Cooper Ladle with transfer conduit
US10052688B2 (en) 2013-03-15 2018-08-21 Molten Metal Equipment Innovations, Llc Transfer pump launder system
US10465688B2 (en) 2014-07-02 2019-11-05 Molten Metal Equipment Innovations, Llc Coupling and rotor shaft for molten metal devices
US10947980B2 (en) 2015-02-02 2021-03-16 Molten Metal Equipment Innovations, Llc Molten metal rotor with hardened blade tips
US10267314B2 (en) 2016-01-13 2019-04-23 Molten Metal Equipment Innovations, Llc Tensioned support shaft and other molten metal devices
US11149747B2 (en) 2017-11-17 2021-10-19 Molten Metal Equipment Innovations, Llc Tensioned support post and other molten metal devices
US11471938B2 (en) 2019-05-17 2022-10-18 Molten Metal Equipment Innovations, Llc Smart molten metal pump
US11873845B2 (en) 2021-05-28 2024-01-16 Molten Metal Equipment Innovations, Llc Molten metal transfer device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1555953A (de) * 1967-02-09 1969-01-31
FR2166014A1 (de) * 1971-12-27 1973-08-10 Union Carbide Corp
US3767382A (en) * 1971-11-04 1973-10-23 Aluminum Co Of America Treatment of molten aluminum with an impeller
US3849119A (en) * 1971-11-04 1974-11-19 Aluminum Co Of America Treatment of molten aluminum with an impeller

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR90350E (fr) * 1965-10-21 1967-11-24 Air Liquide Procédé de traitement des métaux liquides, applicable notamment à l'élaboration de fonte nodulaire
US3651825A (en) * 1969-10-24 1972-03-28 Francis P Sury Stopper plug valve for hot metal ladles

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1555953A (de) * 1967-02-09 1969-01-31
US3767382A (en) * 1971-11-04 1973-10-23 Aluminum Co Of America Treatment of molten aluminum with an impeller
US3849119A (en) * 1971-11-04 1974-11-19 Aluminum Co Of America Treatment of molten aluminum with an impeller
FR2166014A1 (de) * 1971-12-27 1973-08-10 Union Carbide Corp

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2562449A1 (fr) * 1984-04-06 1985-10-11 Servimetal Dispositif de traitement de l'acier, avant coulee continue, par injection de gaz
EP0162789A1 (de) * 1984-04-06 1985-11-27 Servimetal Vorrichtung zur Stahlbehandlung vor Beginn des Stranggiessens durch Einblasen von Gas
FR2629101A1 (fr) * 1988-03-23 1989-09-29 Radex Heraklin Industriebeteil Brique pour l'introduction de gaz ou de produits de reaction dans un recipient de coulee metallurgique
BE1003020A3 (fr) * 1988-03-23 1991-10-29 Radex Heraklith Brique pour l'introduction de gaz ou de produits de reaction dans un recipient de coulee metallurgique.

Also Published As

Publication number Publication date
ES8207229A1 (es) 1982-09-01
YU243581A (en) 1983-10-31
IN155192B (de) 1985-01-12
AU7628281A (en) 1982-04-22
FR2491954A1 (fr) 1982-04-16
DE3162821D1 (en) 1984-04-26
US4372541A (en) 1983-02-08
NO813447L (no) 1982-04-15
CA1165117A (fr) 1984-04-10
RO83654A (ro) 1984-03-15
AU540945B2 (en) 1984-12-06
ES506075A0 (es) 1982-09-01
GR75823B (de) 1984-08-02
FR2491954B1 (de) 1982-10-22
KR830007187A (ko) 1983-10-14
RO83654B (ro) 1984-03-30
OA06917A (fr) 1983-05-31
JPS6160904B2 (de) 1986-12-23
JPS5792146A (en) 1982-06-08
EP0050578B1 (de) 1984-03-21

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