CA3081826A1 - Device and method for continuously removing impurities from molten metal - Google Patents
Device and method for continuously removing impurities from molten metal Download PDFInfo
- Publication number
- CA3081826A1 CA3081826A1 CA3081826A CA3081826A CA3081826A1 CA 3081826 A1 CA3081826 A1 CA 3081826A1 CA 3081826 A CA3081826 A CA 3081826A CA 3081826 A CA3081826 A CA 3081826A CA 3081826 A1 CA3081826 A1 CA 3081826A1
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- Prior art keywords
- molten metal
- flow path
- outlet
- impurity removal
- removal space
- 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.)
- Abandoned
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- 239000002184 metal Substances 0.000 title claims abstract description 286
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 286
- 239000012535 impurity Substances 0.000 title claims abstract description 157
- 238000000034 method Methods 0.000 title claims abstract description 21
- 238000004519 manufacturing process Methods 0.000 claims abstract description 21
- 238000007667 floating Methods 0.000 claims abstract description 10
- 238000005192 partition Methods 0.000 claims abstract description 9
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 abstract description 8
- 238000002844 melting Methods 0.000 description 20
- 230000008018 melting Effects 0.000 description 20
- 239000007788 liquid Substances 0.000 description 8
- 239000002245 particle Substances 0.000 description 8
- 230000005484 gravity Effects 0.000 description 5
- 238000000746 purification Methods 0.000 description 3
- 229910000861 Mg alloy Inorganic materials 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 239000004020 conductor Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 229910052725 zinc Inorganic materials 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- 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
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
- B22D11/045—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds for horizontal casting
-
- 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
- B22D11/10—Supplying or treating molten metal
- B22D11/103—Distributing the molten metal, e.g. using runners, floats, distributors
-
- 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
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/114—Treating the molten metal by using agitating or vibrating means
- B22D11/115—Treating the molten metal by using agitating or vibrating means by using magnetic fields
-
- 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
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/116—Refining the metal
- B22D11/118—Refining the metal by circulating the metal under, over or around weirs
-
- 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
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/116—Refining the metal
- B22D11/119—Refining the metal by filtering
-
- 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
- B22D27/02—Use of electric or magnetic effects
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/04—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like tiltable
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/50—Pouring-nozzles
- B22D41/56—Means for supporting, manipulating or changing a pouring-nozzle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D11/00—Arrangement of elements for electric heating in or on furnaces
- F27D11/12—Arrangement of elements for electric heating in or on furnaces with electromagnetic fields acting directly on the material being heated
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D25/00—Devices or methods for removing incrustations, e.g. slag, metal deposits, dust; Devices or methods for preventing the adherence of slag
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D3/15—Tapping equipment; Equipment for removing or retaining slag
- F27D3/1545—Equipment for removing or retaining slag
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D3/15—Tapping equipment; Equipment for removing or retaining slag
- F27D3/1545—Equipment for removing or retaining slag
- F27D3/159—Equipment for removing or retaining slag for retaining slag during the pouring of the metal or retaining metal during the pouring of the slag
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D2003/0034—Means for moving, conveying, transporting the charge in the furnace or in the charging facilities
- F27D2003/0039—Means for moving, conveying, transporting the charge in the furnace or in the charging facilities comprising magnetic means
Abstract
To provide a device and a method for continuously removing impurities, which enable continuous manufacture of products while removing impurities from non-ferrous molten metal or other molten metal containing impurities with high accuracy. A molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward a metal product manufacturing device is prepared, an inlet-side closed end plate and an outlet-side closed end plate are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space are provided in the impurity removal space, a magnetic field device composed of a pair of permanent magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space is provided outside the molten metal flow path forming body, the outlet-side electrode is provided in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate, and an urging device composed of the electrode device and the magnetic field device applies a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and sends molten metal on an inner side than the outlet-side electrode through the first gap to the second gap.
Description
DESCRIPTION
DEVICE AND METHOD FOR CONTINUOUSLY REMOVING
IMPURITIES FROM MOLTEN METAL
Technical Field [0001]
The present invention relates to a device and a method for continuously removing impurities from molten metal.
Background Art
DEVICE AND METHOD FOR CONTINUOUSLY REMOVING
IMPURITIES FROM MOLTEN METAL
Technical Field [0001]
The present invention relates to a device and a method for continuously removing impurities from molten metal.
Background Art
[0002]
Conventionally, productization from molten metal having electrical conductivity (conductivity), that is, non-ferrous molten metal (e.g., Al, Cu, Zn, or Si, alloy including at least two of these, Mg alloy, or the like) or molten metal other than non-ferrous molten metal includes, for example, steps of dissolving raw materials, adjusting components, removing impurities mixed in molten metal, and molding. Removal of impurities is generally referred to as purification of molten metal, and, for example, a ceramic filter is used therefor.
Conventionally, productization from molten metal having electrical conductivity (conductivity), that is, non-ferrous molten metal (e.g., Al, Cu, Zn, or Si, alloy including at least two of these, Mg alloy, or the like) or molten metal other than non-ferrous molten metal includes, for example, steps of dissolving raw materials, adjusting components, removing impurities mixed in molten metal, and molding. Removal of impurities is generally referred to as purification of molten metal, and, for example, a ceramic filter is used therefor.
[0003]
However, since an impurity removal method using a filter is, of course, a filtration method, clogging is likely to occur.
Therefore, there is a problem such that the workability is deteriorated and the running cost is increased.
However, since an impurity removal method using a filter is, of course, a filtration method, clogging is likely to occur.
Therefore, there is a problem such that the workability is deteriorated and the running cost is increased.
[0004]
In other words, in a case of a filter type, how large the mesh is set to is actually an important point. In order to remove not only large impurities but also fine impurities, the mesh must be fine. However, if the mesh is made fine, clogging is more likely to occur. For example, clogging may occur instantaneously, and production may stop.
In other words, in a case of a filter type, how large the mesh is set to is actually an important point. In order to remove not only large impurities but also fine impurities, the mesh must be fine. However, if the mesh is made fine, clogging is more likely to occur. For example, clogging may occur instantaneously, and production may stop.
[0005]
Thus, conventionally, flux is previously introduced into the molten metal prior to removal with a filter. By such introduction, impurities are changed into substances having a large particle size. As a result, it becomes possible to remove Date Recue/Date Received 2020-05-05 impurities while keeping the mesh large to some extent, and it is possible to increase the removal efficiency (trap efficiency) of the filter. However, it is not preferable to introduce flux into the molten metal in terms of product quality in many cases.
Summary of Invention Technical Problem
Thus, conventionally, flux is previously introduced into the molten metal prior to removal with a filter. By such introduction, impurities are changed into substances having a large particle size. As a result, it becomes possible to remove Date Recue/Date Received 2020-05-05 impurities while keeping the mesh large to some extent, and it is possible to increase the removal efficiency (trap efficiency) of the filter. However, it is not preferable to introduce flux into the molten metal in terms of product quality in many cases.
Summary of Invention Technical Problem
[0006]
As described above, according to a conventional method, it is actually impossible to continuously produce products without stopping production of products while removing impurities, including fine impurities, from molten metal.
As described above, according to a conventional method, it is actually impossible to continuously produce products without stopping production of products while removing impurities, including fine impurities, from molten metal.
[0007]
The present invention has been made in view of such circumstances, and it is an object thereof to provide a device and a method for continuously removing impurities for enabling continuous manufacture of products while removing impurities from non-ferrous metal or other molten metal containing impurities with high accuracy.
Solution to Problem
The present invention has been made in view of such circumstances, and it is an object thereof to provide a device and a method for continuously removing impurities for enabling continuous manufacture of products while removing impurities from non-ferrous metal or other molten metal containing impurities with high accuracy.
Solution to Problem
[0008]
An embodiment of the present invention is a device for continuously removing impurities from molten metal, which sends electrically conductive molten metal to a metal product manufacturing device in a next stage, the device including:
a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
an inlet-side closed end plate and an outlet-side closed end plate that are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
an electrode device composed of an inlet-side electrode and an outlet-side electrode that are provided in the impurity removal space, face each other in a longitudinal direction in Date Recue/Date Received 2020-05-05 which molten metal flows, and can be put into electrical contact with molten metal in the impurity removal space; and a magnetic field device composed of a pair of permanent magnets that are provided outside the molten metal flow path forming body, face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space, in which the electrode device and the magnetic field device constitute an urging device that can apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal.
An embodiment of the present invention is a device for continuously removing impurities from molten metal, which sends electrically conductive molten metal to a metal product manufacturing device in a next stage, the device including:
a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
an inlet-side closed end plate and an outlet-side closed end plate that are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
an electrode device composed of an inlet-side electrode and an outlet-side electrode that are provided in the impurity removal space, face each other in a longitudinal direction in Date Recue/Date Received 2020-05-05 which molten metal flows, and can be put into electrical contact with molten metal in the impurity removal space; and a magnetic field device composed of a pair of permanent magnets that are provided outside the molten metal flow path forming body, face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space, in which the electrode device and the magnetic field device constitute an urging device that can apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal.
[0009]
Furthermore, an embodiment of the present invention is a continuous impurity removal method for removing impurities from molten metal in sending electrically conductive molten metal to a metal product manufacturing device in a next stage, the method including:
preparing a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
providing an inlet-side closed end plate and an outlet-side closed end plate in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
providing, in the impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space;
providing, outside the molten metal flow path forming body, a magnetic field device composed of a pair of permanent Date Recue/Date Received 2020-05-05 magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space;
and causing an urging device composed of the electrode device and the magnetic field device to apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal.
Furthermore, an embodiment of the present invention is a continuous impurity removal method for removing impurities from molten metal in sending electrically conductive molten metal to a metal product manufacturing device in a next stage, the method including:
preparing a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
providing an inlet-side closed end plate and an outlet-side closed end plate in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
providing, in the impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space;
providing, outside the molten metal flow path forming body, a magnetic field device composed of a pair of permanent Date Recue/Date Received 2020-05-05 magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space;
and causing an urging device composed of the electrode device and the magnetic field device to apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal.
[0010]
Furthermore, an embodiment of the present invention is a device for continuously removing impurities from molten metal, which sends electrically conductive molten metal to a metal product manufacturing device in a next stage, the device including:
a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
an inlet-side closed end plate and an outlet-side closed end plate that are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
an electrode device composed of an inlet-side electrode and an outlet-side electrode that are provided in the impurity removal space, face each other in a longitudinal direction in which molten metal flows, and can be put into electrical contact with molten metal in the impurity removal space; and a magnetic field device composed of a pair of permanent magnets that are provided outside the molten metal flow path forming body, face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a Date Recue/Date Received 2020-05-05 magnetic field in molten metal in the impurity removal space, in which the outlet-side electrode is provided in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a 5 bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate, and the electrode device and the magnetic field device, and the electrode device and the magnetic field device constitute an urging device that can apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and can send molten metal on an inner side than the outlet-side electrode in the impurity removal space through the first gap to the second gap.
Furthermore, an embodiment of the present invention is a device for continuously removing impurities from molten metal, which sends electrically conductive molten metal to a metal product manufacturing device in a next stage, the device including:
a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
an inlet-side closed end plate and an outlet-side closed end plate that are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
an electrode device composed of an inlet-side electrode and an outlet-side electrode that are provided in the impurity removal space, face each other in a longitudinal direction in which molten metal flows, and can be put into electrical contact with molten metal in the impurity removal space; and a magnetic field device composed of a pair of permanent magnets that are provided outside the molten metal flow path forming body, face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a Date Recue/Date Received 2020-05-05 magnetic field in molten metal in the impurity removal space, in which the outlet-side electrode is provided in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a 5 bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate, and the electrode device and the magnetic field device, and the electrode device and the magnetic field device constitute an urging device that can apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and can send molten metal on an inner side than the outlet-side electrode in the impurity removal space through the first gap to the second gap.
[0011]
Furthermore, an embodiment of the present invention is a continuous impurity removal method for removing impurities from molten metal in sending electrically conductive molten metal to a metal product manufacturing device in a next stage, the method including:
preparing a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
providing an inlet-side closed end plate and an outlet-side closed end plate in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
providing, in the impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space;
Date Recue/Date Received 2020-05-05 providing, outside the molten metal flow path forming body, a magnetic field device composed of a pair of permanent magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space;
providing the outlet-side electrode in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate; and causing an urging device composed of the electrode device and the magnetic field device to apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and send molten metal on an inner side than the outlet-side electrode through the first gap to the second gap.
Brief Description of Drawings
Furthermore, an embodiment of the present invention is a continuous impurity removal method for removing impurities from molten metal in sending electrically conductive molten metal to a metal product manufacturing device in a next stage, the method including:
preparing a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
providing an inlet-side closed end plate and an outlet-side closed end plate in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
providing, in the impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space;
Date Recue/Date Received 2020-05-05 providing, outside the molten metal flow path forming body, a magnetic field device composed of a pair of permanent magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space;
providing the outlet-side electrode in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate; and causing an urging device composed of the electrode device and the magnetic field device to apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and send molten metal on an inner side than the outlet-side electrode through the first gap to the second gap.
Brief Description of Drawings
[0012]
FIG. 1 is an explanatory plan view illustrating the overall configuration of a device for continuously removing impurities from molten metal according to an embodiment of the present invention.
FIG. 2 is an explanatory sectional view taken along line II-II of FIG. 1.
FIG. 3 is an explanatory sectional view taken along line III-III of FIG. 2.
FIG. 4 is an explanatory sectional view taken along line IV-IV of FIG. 2.
FIG. 5 is an explanatory view illustrating a usage state corresponding to a part of FIG. 2.
FIG. 6 is an explanatory view for explaining generation of Date Recue/Date Received 2020-05-05 a Lorentz force.
FIG. 7(a) is an explanatory view for explaining a pressure state in molten metal.
FIG. 7(b) is an explanatory view for explaining a pressure state in molten metal.
FIG. 8 is an explanatory partial view illustrating a modified example corresponding to FIG. 5.
FIG. 9(a) is an explanatory longitudinal sectional view illustrating a specific example of an outlet-side closed end plate.
FIG. 9(b) is an explanatory longitudinal sectional view illustrating a specific example of an outlet-side closed end plate.
Description of Embodiments
FIG. 1 is an explanatory plan view illustrating the overall configuration of a device for continuously removing impurities from molten metal according to an embodiment of the present invention.
FIG. 2 is an explanatory sectional view taken along line II-II of FIG. 1.
FIG. 3 is an explanatory sectional view taken along line III-III of FIG. 2.
FIG. 4 is an explanatory sectional view taken along line IV-IV of FIG. 2.
FIG. 5 is an explanatory view illustrating a usage state corresponding to a part of FIG. 2.
FIG. 6 is an explanatory view for explaining generation of Date Recue/Date Received 2020-05-05 a Lorentz force.
FIG. 7(a) is an explanatory view for explaining a pressure state in molten metal.
FIG. 7(b) is an explanatory view for explaining a pressure state in molten metal.
FIG. 8 is an explanatory partial view illustrating a modified example corresponding to FIG. 5.
FIG. 9(a) is an explanatory longitudinal sectional view illustrating a specific example of an outlet-side closed end plate.
FIG. 9(b) is an explanatory longitudinal sectional view illustrating a specific example of an outlet-side closed end plate.
Description of Embodiments
[0013]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
FIG. 1 is an explanatory plan view illustrating the entire configuration of an embodiment of a device 100 for continuously removing impurities from molten metal according to the present invention. The metal is a non-ferrous metal having electrical conductivity or another metal. The non-ferrous metal or another metal is a non-ferrous metal of a conductor (electric conductor) such as Al, Cu, Zn, an alloy including at least two of these, or an Mg alloy, or a metal other than the non-ferrous metal.
FIG. 1 is an explanatory plan view illustrating the entire configuration of an embodiment of a device 100 for continuously removing impurities from molten metal according to the present invention. The metal is a non-ferrous metal having electrical conductivity or another metal. The non-ferrous metal or another metal is a non-ferrous metal of a conductor (electric conductor) such as Al, Cu, Zn, an alloy including at least two of these, or an Mg alloy, or a metal other than the non-ferrous metal.
[0015]
In FIG. 1, the flow of molten metal M is indicated by a solid arrow AR1, and the movement of impurities IM is indicated by a broken arrow AR2. That is, it is shown that the impurities IM are removed laterally while the molten metal M is flowing along the arrow AR1.
In FIG. 1, the flow of molten metal M is indicated by a solid arrow AR1, and the movement of impurities IM is indicated by a broken arrow AR2. That is, it is shown that the impurities IM are removed laterally while the molten metal M is flowing along the arrow AR1.
[0016]
More specifically, FIG. 1 illustrates a case where a tilting type melting furnace is used as an example. As can be seen from FIG. 1, the impurity removing device 100 receives molten metal M from a melting furnace 200 in the preceding stage, Date Recue/Date Received 2020-05-05 allows the molten metal M flow inside the impurity removing device 100, causes impurities in the molten metal M to positively rise up to the vicinity of the liquid surface during the molten metal M is flowing so that the impurities can be removed by arbitral means, and causes the molten metal M to flow into a mold 300 in the following stage after impurities are removed, so that a product (ingot) such as a billet or a slab, for example, can be manufactured from high-quality molten metal M. A
general-purpose melting furnace 200 and a general-purpose mold 300 can be employed. Therefore, for example, the impurity removing device 100 of the present invention can be additionally provided to an existing melting furnace 200 and an existing mold 300 later.
More specifically, FIG. 1 illustrates a case where a tilting type melting furnace is used as an example. As can be seen from FIG. 1, the impurity removing device 100 receives molten metal M from a melting furnace 200 in the preceding stage, Date Recue/Date Received 2020-05-05 allows the molten metal M flow inside the impurity removing device 100, causes impurities in the molten metal M to positively rise up to the vicinity of the liquid surface during the molten metal M is flowing so that the impurities can be removed by arbitral means, and causes the molten metal M to flow into a mold 300 in the following stage after impurities are removed, so that a product (ingot) such as a billet or a slab, for example, can be manufactured from high-quality molten metal M. A
general-purpose melting furnace 200 and a general-purpose mold 300 can be employed. Therefore, for example, the impurity removing device 100 of the present invention can be additionally provided to an existing melting furnace 200 and an existing mold 300 later.
[0017]
The melting furnace 200 is a general-purpose tilting type melting furnace as described above. That is, the melting furnace 200 includes a container-shaped melting furnace main body 1 having an opening 2 at the top. A spout 3 for the molten metal M is formed at a side wall on the front side (left side in the figure) of the tilting type melting furnace main body 1. A general-purpose gas burner 4 is attached to a rear side wall. The raw material of the electrically conductive metal introduced from the opening 2 is heated by the gas burner 4 to be molten metal M and is housed in the melting furnace main body 1.
The melting furnace 200 is a general-purpose tilting type melting furnace as described above. That is, the melting furnace 200 includes a container-shaped melting furnace main body 1 having an opening 2 at the top. A spout 3 for the molten metal M is formed at a side wall on the front side (left side in the figure) of the tilting type melting furnace main body 1. A general-purpose gas burner 4 is attached to a rear side wall. The raw material of the electrically conductive metal introduced from the opening 2 is heated by the gas burner 4 to be molten metal M and is housed in the melting furnace main body 1.
[0018]
FIG. 2 is an explanatory longitudinal sectional view taken along line II-II of FIG. 1. As can be seen from FIG. 2, a hinge mechanism 6 is provided at an outer bottom portion of the melting furnace main body 1 so as to be able to derrick and rotate. As a result, it is configured to be able to derrick and rotate on a horizontal shaft 6a from an upright state to an inclined pouring state. This melting furnace main body 1 can adjust the amount of molten metal supplied to a gutter main body 10. The molten metal M is poured from the spout 3 to the impurity removing device 100 in the next stage by tilting the Date Recue/Date Received 2020-05-05 melting furnace main body 1. This state is illustrated in FIG. 5.
By adjusting the angle at which the melting furnace main body 1 is inclined, the head h illustrated in FIG. 2 is changed, and the flow rate of the molten metal M from the melting furnace main body 1 to the gutter main body 10 can be changed. It is to be noted that the level of the molten metal M in the gutter main body 10 is performed by changing the height of an outlet-side closed end plate 11. Moreover, as illustrated in FIG. 8, one electrode 13b, which will be described later, can be provided separately from the inlet-side closed end plate 8. The flow of the molten metal M at this time is as illustrated in FIG. 8.
FIG. 2 is an explanatory longitudinal sectional view taken along line II-II of FIG. 1. As can be seen from FIG. 2, a hinge mechanism 6 is provided at an outer bottom portion of the melting furnace main body 1 so as to be able to derrick and rotate. As a result, it is configured to be able to derrick and rotate on a horizontal shaft 6a from an upright state to an inclined pouring state. This melting furnace main body 1 can adjust the amount of molten metal supplied to a gutter main body 10. The molten metal M is poured from the spout 3 to the impurity removing device 100 in the next stage by tilting the Date Recue/Date Received 2020-05-05 melting furnace main body 1. This state is illustrated in FIG. 5.
By adjusting the angle at which the melting furnace main body 1 is inclined, the head h illustrated in FIG. 2 is changed, and the flow rate of the molten metal M from the melting furnace main body 1 to the gutter main body 10 can be changed. It is to be noted that the level of the molten metal M in the gutter main body 10 is performed by changing the height of an outlet-side closed end plate 11. Moreover, as illustrated in FIG. 8, one electrode 13b, which will be described later, can be provided separately from the inlet-side closed end plate 8. The flow of the molten metal M at this time is as illustrated in FIG. 8.
[0019]
The impurity removing device 100 that receives the molten metal M from the melting furnace 200 is configured to have a function as a so-called gutter that allows the received molten metal M flow from right to left in FIG. 1 and give the molten metal M to the mold 300 in the next stage, and a selective accumulation function of selectively accumulating impurities in the molten metal M that are caused to rise up to the vicinity of the liquid surface during the flow.
The impurity removing device 100 that receives the molten metal M from the melting furnace 200 is configured to have a function as a so-called gutter that allows the received molten metal M flow from right to left in FIG. 1 and give the molten metal M to the mold 300 in the next stage, and a selective accumulation function of selectively accumulating impurities in the molten metal M that are caused to rise up to the vicinity of the liquid surface during the flow.
[0020]
That is, as can be seen particularly from FIG. 2, the impurity removing device 100 includes the gutter main body (sorting tank) (molten metal flow path body) 10, and a magnetic field device 12 that sandwiches the gutter main body 10 in the width direction.
Furthermore, as can be seen particularly from FIG. 1, the impurity removing device 100 has an electrode device 13 composed of a pair of electrodes 13a and 13b that are housed inside the gutter main body 10 (molten metal flow path) and face each other. The magnetic field device 12 and the electrode device 13 constitute an urging device 30 that applies a Lorentz force f downward to the molten metal M, as will be described later in detail.
That is, as can be seen particularly from FIG. 2, the impurity removing device 100 includes the gutter main body (sorting tank) (molten metal flow path body) 10, and a magnetic field device 12 that sandwiches the gutter main body 10 in the width direction.
Furthermore, as can be seen particularly from FIG. 1, the impurity removing device 100 has an electrode device 13 composed of a pair of electrodes 13a and 13b that are housed inside the gutter main body 10 (molten metal flow path) and face each other. The magnetic field device 12 and the electrode device 13 constitute an urging device 30 that applies a Lorentz force f downward to the molten metal M, as will be described later in detail.
[0021]
As can be seen from FIG. 1, the gutter main body 10 is configured to guide the molten metal M from the melting Date Recue/Date Received 2020-05-05 furnace 200 to the mold 300, and the gutter main body 10 is made of a refractory material and has a substantially U-shaped cross section as can be seen from FIG. 3. The gutter main body 10 can be installed with a gradient so that the left side 5 becomes lower than the right side in FIG. 2 in order to make the flow of the molten metal M smooth.
As can be seen from FIG. 1, the gutter main body 10 is configured to guide the molten metal M from the melting Date Recue/Date Received 2020-05-05 furnace 200 to the mold 300, and the gutter main body 10 is made of a refractory material and has a substantially U-shaped cross section as can be seen from FIG. 3. The gutter main body 10 can be installed with a gradient so that the left side 5 becomes lower than the right side in FIG. 2 in order to make the flow of the molten metal M smooth.
[0022]
As can be seen from FIG. 2, the gutter main body 10 has an inflow auxiliary plate 7A that receives the molten metal M
10 from the melting furnace 200, and an inlet-side closed end plate 8, a main flow path bottom plate 9, and the outlet-side closed end plate 11 that follow. Furthermore, there are right and left side plates 15a and 15b sandwiching these members in the width direction. The right and left side plates 15a and 15b, the inlet-side closed end plate 8, and the outlet-side closed end plate 11 form a main flow path (impurity removal space) 14 as an impurity removal portion.
As can be seen from FIG. 2, the gutter main body 10 has an inflow auxiliary plate 7A that receives the molten metal M
10 from the melting furnace 200, and an inlet-side closed end plate 8, a main flow path bottom plate 9, and the outlet-side closed end plate 11 that follow. Furthermore, there are right and left side plates 15a and 15b sandwiching these members in the width direction. The right and left side plates 15a and 15b, the inlet-side closed end plate 8, and the outlet-side closed end plate 11 form a main flow path (impurity removal space) 14 as an impurity removal portion.
[0023]
The outlet-side closed end plate 11 can be configured such that the height thereof can be adjusted. Arbitral configuration configured such that the height thereof can be adjusted can be employed. For example, as can be seen from FIGS. 9(a) and 9(b), the outlet-side closed end plate 11 may be composed of a main body 11a and an auxiliary plate 11b which are bolted to each other, and the auxiliary plate 11b may be vertically shifted with respect to the main body 11a.
The outlet-side closed end plate 11 can be configured such that the height thereof can be adjusted. Arbitral configuration configured such that the height thereof can be adjusted can be employed. For example, as can be seen from FIGS. 9(a) and 9(b), the outlet-side closed end plate 11 may be composed of a main body 11a and an auxiliary plate 11b which are bolted to each other, and the auxiliary plate 11b may be vertically shifted with respect to the main body 11a.
[0024]
The inlet-side electrode 13a in the electrode device 13 is provided in close contact with the inlet-side closed end plate 8, and the outlet-side electrode 13b is spaced from the outlet-side closed end plate 11 with a gap (second gap) G2 in the longitudinal direction and is provided in a floating state of floating with a gap (first gap) G1 in the depth direction. As a result, the molten metal M flows through the gaps G1 and G2, flows over the outlet-side closed end plate 11, or so-called overflows, and flows out from the main flow path 8 through an Date Recue/Date Received 2020-05-05 outflow auxiliary plate 78 toward the mold 300 as will be described later.
The inlet-side electrode 13a in the electrode device 13 is provided in close contact with the inlet-side closed end plate 8, and the outlet-side electrode 13b is spaced from the outlet-side closed end plate 11 with a gap (second gap) G2 in the longitudinal direction and is provided in a floating state of floating with a gap (first gap) G1 in the depth direction. As a result, the molten metal M flows through the gaps G1 and G2, flows over the outlet-side closed end plate 11, or so-called overflows, and flows out from the main flow path 8 through an Date Recue/Date Received 2020-05-05 outflow auxiliary plate 78 toward the mold 300 as will be described later.
[0025]
A power supply 16 is connected between the pair of electrodes 13a and 13b in the electrode device 13. This power supply 16 is configured to be able to pass an alternating current as well as a direct current. Furthermore, it is configured to switch the polarity of a direct current.
A power supply 16 is connected between the pair of electrodes 13a and 13b in the electrode device 13. This power supply 16 is configured to be able to pass an alternating current as well as a direct current. Furthermore, it is configured to switch the polarity of a direct current.
[0026]
The magnetic field device 12 is provided on both right and left sides of the gutter main body 10 as can be seen from FIGS. 1 and 4. This magnetic field device 12 includes a pair of right and left permanent magnets 12a and 12b, and the gutter main body 10 is sandwiched between the pair of permanent magnets 12a and 12b. The pair of permanent magnets 12a and 12b have opposite poles facing each other, and in this embodiment, the inner sides of the pair of permanent magnets 12a and 12b are magnetized respectively to an S pole and an N
pole. As a result, the lines of magnetic force ML from an upper permanent magnet 12b in FIG. 4 penetrate the molten metal M
in the gutter main body 10 and reach a lower permanent magnet 12a. Thus, in actual use, a current I flows between the pair of electrodes 13a and 13b as can be seen from FIG. 4.
Therefore, the lines of magnetic force ML and the current I
intersect each other. As a result, a Lorentz force f to push the molten metal M downward is generated in the molten metal M
as illustrated in FIG. 6. It is to be noted that the magnetic field device 12 can be constituted of an electromagnet.
The magnetic field device 12 is provided on both right and left sides of the gutter main body 10 as can be seen from FIGS. 1 and 4. This magnetic field device 12 includes a pair of right and left permanent magnets 12a and 12b, and the gutter main body 10 is sandwiched between the pair of permanent magnets 12a and 12b. The pair of permanent magnets 12a and 12b have opposite poles facing each other, and in this embodiment, the inner sides of the pair of permanent magnets 12a and 12b are magnetized respectively to an S pole and an N
pole. As a result, the lines of magnetic force ML from an upper permanent magnet 12b in FIG. 4 penetrate the molten metal M
in the gutter main body 10 and reach a lower permanent magnet 12a. Thus, in actual use, a current I flows between the pair of electrodes 13a and 13b as can be seen from FIG. 4.
Therefore, the lines of magnetic force ML and the current I
intersect each other. As a result, a Lorentz force f to push the molten metal M downward is generated in the molten metal M
as illustrated in FIG. 6. It is to be noted that the magnetic field device 12 can be constituted of an electromagnet.
[0027]
Next, the operation of the embodiment of the present invention will be described.
Next, the operation of the embodiment of the present invention will be described.
[0028]
As can be seen from FIGS. 1 and 2, when electrically conductive metal is introduced into the melting furnace 200 and is heated and molten, the molten metal M is caused to flow from the melting furnace 200 into the main flow path 14 by increase Date Recue/Date Received 2020-05-05 of the molten metal M and the tilt illustrated in FIG. 5.
As can be seen from FIGS. 1 and 2, when electrically conductive metal is introduced into the melting furnace 200 and is heated and molten, the molten metal M is caused to flow from the melting furnace 200 into the main flow path 14 by increase Date Recue/Date Received 2020-05-05 of the molten metal M and the tilt illustrated in FIG. 5.
[0029]
In this main flow path 14, the lines of magnetic force ML
and the current I intersect each other as can be seen from FIG.
4. This concept is illustrated in FIG. 6 described above. As a result, a Lorentz force f is generated and acts on the molten metal M as a force in a direction to push the molten metal M
downward. As a result, the pressure inside the molten metal M
increases as it goes from the surface to a bottom portion. The state of pressure distribution in this case is illustrated in FIG.
7(a). That is, the density of the molten metal M becomes larger toward the bottom portion due to the gravity in addition to the Lorentz force f. This density affects greatly the buoyancy of impurities IM contained in the molten metal M.
That is, when the density is high, a large buoyancy acts on impurities IM.
In this main flow path 14, the lines of magnetic force ML
and the current I intersect each other as can be seen from FIG.
4. This concept is illustrated in FIG. 6 described above. As a result, a Lorentz force f is generated and acts on the molten metal M as a force in a direction to push the molten metal M
downward. As a result, the pressure inside the molten metal M
increases as it goes from the surface to a bottom portion. The state of pressure distribution in this case is illustrated in FIG.
7(a). That is, the density of the molten metal M becomes larger toward the bottom portion due to the gravity in addition to the Lorentz force f. This density affects greatly the buoyancy of impurities IM contained in the molten metal M.
That is, when the density is high, a large buoyancy acts on impurities IM.
[0030]
Therefore, in a state in which the Lorentz force f is generated, impurities IM in the molten metal M rise in the molten metal M and reach the liquid level. That is, impurities IM tend to settle in the molten metal M by its own weight.
Moreover, a buoyancy due to the molten metal M acts on impurities IM. Thus, when the density of the molten metal M
increases, a large buoyancy acts on impurities IM in the molten metal M. Therefore, impurities IM rise or fall according to a difference between the buoyancy and the settlement force.
Thus, by setting the Lorentz force f to an expected value, the buoyancy becomes larger than the settlement force, and impurities IM rise in the molten metal M and reach the vicinity of the liquid surface. This operation is continuously performed in the process of flow of the molten metal M through the main flow path 14.
Therefore, in a state in which the Lorentz force f is generated, impurities IM in the molten metal M rise in the molten metal M and reach the liquid level. That is, impurities IM tend to settle in the molten metal M by its own weight.
Moreover, a buoyancy due to the molten metal M acts on impurities IM. Thus, when the density of the molten metal M
increases, a large buoyancy acts on impurities IM in the molten metal M. Therefore, impurities IM rise or fall according to a difference between the buoyancy and the settlement force.
Thus, by setting the Lorentz force f to an expected value, the buoyancy becomes larger than the settlement force, and impurities IM rise in the molten metal M and reach the vicinity of the liquid surface. This operation is continuously performed in the process of flow of the molten metal M through the main flow path 14.
[0031]
In this way, impurities IM rise up to the vicinity of the surface of the molten metal M. Impurities IM that have risen up are automatically or artificially discharged to an impurity Date Recue/Date Received 2020-05-05 receiver 40 via the impurity removing plate 7C as can be seen from FIG. 3 by arbitral means. As illustrated in FIG. 3, the impurity removing plate 7C has a mountain-shaped cross section.
In this way, impurities IM rise up to the vicinity of the surface of the molten metal M. Impurities IM that have risen up are automatically or artificially discharged to an impurity Date Recue/Date Received 2020-05-05 receiver 40 via the impurity removing plate 7C as can be seen from FIG. 3 by arbitral means. As illustrated in FIG. 3, the impurity removing plate 7C has a mountain-shaped cross section.
[0032]
Moreover, in the gutter main body 10, the molten metal M is pushed down by application of pressure as illustrated in FIG.
7(b) as described above to decrease the liquid level. Along with this, the molten metal M flows through the gap G1 and reaches the gap G2 as can be seen from FIG. 2. As a result, a head h is generated, and a pressure corresponding to the head h is applied to the molten metal M in the gutter main body 10 as illustrated in FIG. 2. Here, since impurities IM rise in the molten metal M and gather in the vicinity of the liquid surface, the molten metal M flowing through the gap G1 contains substantially no impurity IM. That is, molten metal M
substantially containing no impurity IM exists in the gap G2.
Thus, the liquid level of the molten metal M rises in the gap G2.
Therefore, the substantially purified molten metal M flows over the outlet-side closed end plate 11 and flows into the mold 30 via the outflow auxiliary plate 7B. As a result, a high-quality product with less impurities IM can be obtained. In FIG. 2, h denotes a head of two liquid levels.
Moreover, in the gutter main body 10, the molten metal M is pushed down by application of pressure as illustrated in FIG.
7(b) as described above to decrease the liquid level. Along with this, the molten metal M flows through the gap G1 and reaches the gap G2 as can be seen from FIG. 2. As a result, a head h is generated, and a pressure corresponding to the head h is applied to the molten metal M in the gutter main body 10 as illustrated in FIG. 2. Here, since impurities IM rise in the molten metal M and gather in the vicinity of the liquid surface, the molten metal M flowing through the gap G1 contains substantially no impurity IM. That is, molten metal M
substantially containing no impurity IM exists in the gap G2.
Thus, the liquid level of the molten metal M rises in the gap G2.
Therefore, the substantially purified molten metal M flows over the outlet-side closed end plate 11 and flows into the mold 30 via the outflow auxiliary plate 7B. As a result, a high-quality product with less impurities IM can be obtained. In FIG. 2, h denotes a head of two liquid levels.
[0033]
The above-described fact that application of the Lorentz force f can cause impurities IM in the molten metal M to rise in the molten metal M will be described below in detail.
The above-described fact that application of the Lorentz force f can cause impurities IM in the molten metal M to rise in the molten metal M will be described below in detail.
[0034]
The magnetic field strength in the molten metal M in FIG.
4 will be denoted by B. Here, as can be seen from FIGS. 7(a) and 7(b), it is assumed that a Lorentz force f is generated downward. At this time, a force F that acts on a bottom portion of the gutter main body 10 is the sum of a force fg due to the gravity and a force fm due to the Lorentz force f, and is expressed as the following expression.
F = fg + fm Date Regue/Date Received 2020-05-05
The magnetic field strength in the molten metal M in FIG.
4 will be denoted by B. Here, as can be seen from FIGS. 7(a) and 7(b), it is assumed that a Lorentz force f is generated downward. At this time, a force F that acts on a bottom portion of the gutter main body 10 is the sum of a force fg due to the gravity and a force fm due to the Lorentz force f, and is expressed as the following expression.
F = fg + fm Date Regue/Date Received 2020-05-05
[0035]
Here, since the horizontal area A of the gutter main body is A = Ixa (I: the length of the gutter main body 10, a: the width of the gutter main body 10), the pressure P at a bottom 5 portion of the gutter main body 10 is expressed as the following expression.
P = F/A Furthermore, assuming here that the current density between the pair of electrodes 13a and 13b is constant, the Lorentz force f becomes zero at the surface of the molten 10 metal, and IxBx1 (N) at a bottom portion. Thus, the pressure is highest at a bottom portion. This state is illustrated in FIGS.
7(a) and 7(b).
Here, since the horizontal area A of the gutter main body is A = Ixa (I: the length of the gutter main body 10, a: the width of the gutter main body 10), the pressure P at a bottom 5 portion of the gutter main body 10 is expressed as the following expression.
P = F/A Furthermore, assuming here that the current density between the pair of electrodes 13a and 13b is constant, the Lorentz force f becomes zero at the surface of the molten 10 metal, and IxBx1 (N) at a bottom portion. Thus, the pressure is highest at a bottom portion. This state is illustrated in FIGS.
7(a) and 7(b).
[0036]
Furthermore, the apparent density of the molten metal M
affected by two influences of the Lorentz force f and the gravity is denoted by pm, the density of mixed impurity particles is denoted by ps, and the particle size is denoted by V. The buoyancy fa received from the molten metal M and the force fg due to the gravity simultaneously act on the impurity particles.
At this time, assuming that the force received by the impurity particles is denoted by Fs, the following expression is satisfied.
Fs = fa - fg = pnnxV - psxV
= (pm - ps)xV Accordingly, the impurity particles move in the molten metal M as follows.
(a) pm - ps > 0 Rise (b) pm - ps < 0 Settlement (c) pm - ps = 0 Floating
Furthermore, the apparent density of the molten metal M
affected by two influences of the Lorentz force f and the gravity is denoted by pm, the density of mixed impurity particles is denoted by ps, and the particle size is denoted by V. The buoyancy fa received from the molten metal M and the force fg due to the gravity simultaneously act on the impurity particles.
At this time, assuming that the force received by the impurity particles is denoted by Fs, the following expression is satisfied.
Fs = fa - fg = pnnxV - psxV
= (pm - ps)xV Accordingly, the impurity particles move in the molten metal M as follows.
(a) pm - ps > 0 Rise (b) pm - ps < 0 Settlement (c) pm - ps = 0 Floating
[0037]
With the embodiment of the present invention described above, the following advantages can be obtained.
With the embodiment of the present invention described above, the following advantages can be obtained.
[0038]
(1) Continuous purification of molten metal M is possible, which is consistent with a continuous casting method that has become a standard technology in the industry.
(2) Although the rise speed of impurities varies Date Recue/Date Received 2020-05-05 depending on the particle size, density, and the like of impurities, the residence time of the molten metal M in the gutter main body (sorting tank) may be increased by slowing down the flow speed or lengthening the gutter main body, for 5 example, in the case of separating objects (having small particle size) having a low rise speed.
(3) Since the purification is neither physical nor mechanical, there is no need to replace a filter, which not only improves the work efficiency but also reduces costs.
10 (4) The specific gravity of the molten metal can be easily changed by changing the magnetic field strength or the current value, and an impurity removing operation can be performed according to the type of the molten metal M to be subjected to impurity removal.
Date Regue/Date Received 2020-05-05
(1) Continuous purification of molten metal M is possible, which is consistent with a continuous casting method that has become a standard technology in the industry.
(2) Although the rise speed of impurities varies Date Recue/Date Received 2020-05-05 depending on the particle size, density, and the like of impurities, the residence time of the molten metal M in the gutter main body (sorting tank) may be increased by slowing down the flow speed or lengthening the gutter main body, for 5 example, in the case of separating objects (having small particle size) having a low rise speed.
(3) Since the purification is neither physical nor mechanical, there is no need to replace a filter, which not only improves the work efficiency but also reduces costs.
10 (4) The specific gravity of the molten metal can be easily changed by changing the magnetic field strength or the current value, and an impurity removing operation can be performed according to the type of the molten metal M to be subjected to impurity removal.
Date Regue/Date Received 2020-05-05
Claims (14)
1. A device for continuously removing impurities from molten metal, which sends electrically conductive molten metal to a metal product manufacturing device in a next stage, the device comprising:
a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
an inlet-side closed end plate and an outlet-side closed end plate that are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
an electrode device composed of an inlet-side electrode and an outlet-side electrode that are provided in the impurity removal space, face each other in a longitudinal direction in which molten metal flows, and can be put into electrical contact with molten metal in the impurity removal space; and a magnetic field device composed of a pair of permanent magnets that are provided outside the molten metal flow path forming body, face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space, wherein the electrode device and the magnetic field device constitute an urging device that can apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal.
a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
an inlet-side closed end plate and an outlet-side closed end plate that are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
an electrode device composed of an inlet-side electrode and an outlet-side electrode that are provided in the impurity removal space, face each other in a longitudinal direction in which molten metal flows, and can be put into electrical contact with molten metal in the impurity removal space; and a magnetic field device composed of a pair of permanent magnets that are provided outside the molten metal flow path forming body, face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space, wherein the electrode device and the magnetic field device constitute an urging device that can apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal.
2. The device for continuously removing impurities from molten metal according to claim 1, wherein a power supply that can adjust an amount of current so as to adjust the Lorentz force is connected with the pair of electrodes in the electrode device.
3. The device for continuously removing impurities from molten metal according to claim 1 or 2, wherein the outlet-side closed end plate is configured to be capable of adjusting a mounting position in the molten metal flow path body in the longitudinal direction so as to adjust a length of the impurity removal space.
4. The device for continuously removing impurities from molten metal according to any one of claims 1 to 3, wherein the outlet-side electrode is provided in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate.
5. The device for continuously removing impurities from molten metal according to any one of claims 1 to 4, wherein the outlet-side closed end plate is configured such that a height of the outlet-side closed end plate can be adjusted so that an amount of molten metal that overflows can be adjusted.
6. The device for continuously removing impurities from molten metal according to any one of claims 1 to 5, wherein a molten metal supply device that supplies molten metal to the molten metal flow path body and can adjust a supply amount is provided in a preceding stage of the molten metal flow path body.
7. A continuous impurity removal method for removing impurities from molten metal in sending electrically conductive molten metal to a metal product manufacturing device in a next stage, the method comprising:
preparing a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
providing an inlet-side closed end plate and an outlet-side closed end plate in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
providing, in the impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space;
providing, outside the molten metal flow path forming body, a magnetic field device composed of a pair of permanent magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space;
and causing an urging device composed of the electrode device and the magnetic field device to apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal.
preparing a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
providing an inlet-side closed end plate and an outlet-side closed end plate in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
providing, in the impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space;
providing, outside the molten metal flow path forming body, a magnetic field device composed of a pair of permanent magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space;
and causing an urging device composed of the electrode device and the magnetic field device to apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal.
8. The method for continuously removing impurities from molten metal according to claim 7, further comprising adjusting an amount of current applied from a power supply to the pair of electrodes in the electrode device so as to adjust the Lorentz force.
9. The method for continuously removing impurities from molten metal according to claim 7 or 8, further comprising a step of adjusting a mounting position of the outlet-side closed end plate in the molten metal flow path body in the longitudinal direction so as to adjust a length of the impurity removal space.
10. The method for continuously removing impurities from molten metal according to any one of claims 7 to 9, wherein the outlet-side electrode is provided in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate.
11. The method for continuously removing impurities from molten metal according to any one of claims 7 to 10, wherein the outlet-side closed end plate is configured such that a height of the outlet-side closed end plate can be adjusted and an amount of molten metal that overflows can be adjusted.
12. The method for continuously removing impurities according to any one of claims 7 to 11, wherein a molten metal supply device provided in a preceding stage of the molten metal flow path body adjusts an amount of molten metal supplied to the molten metal flow path body.
13. A device for continuously removing impurities from molten metal, which sends electrically conductive molten metal to a metal product manufacturing device in a next stage, the device comprising:
a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
an inlet-side closed end plate and an outlet-side closed end plate that are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
an electrode device composed of an inlet-side electrode and an outlet-side electrode that are provided in the impurity removal space, face each other in a longitudinal direction in which molten metal flows, and can be put into electrical contact with molten metal in the impurity removal space; and a magnetic field device composed of a pair of permanent magnets that are provided outside the molten metal flow path forming body, face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space, wherein the outlet-side electrode is provided in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate, and the electrode device and the magnetic field device constitute an urging device that can apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and can send molten metal on an inner side than the outlet-side electrode in the impurity removal space through the first gap to the second gap.
a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
an inlet-side closed end plate and an outlet-side closed end plate that are provided in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
an electrode device composed of an inlet-side electrode and an outlet-side electrode that are provided in the impurity removal space, face each other in a longitudinal direction in which molten metal flows, and can be put into electrical contact with molten metal in the impurity removal space; and a magnetic field device composed of a pair of permanent magnets that are provided outside the molten metal flow path forming body, face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space, wherein the outlet-side electrode is provided in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate, and the electrode device and the magnetic field device constitute an urging device that can apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and can send molten metal on an inner side than the outlet-side electrode in the impurity removal space through the first gap to the second gap.
14. A continuous impurity removal method for removing impurities from molten metal in sending electrically conductive molten metal to a metal product manufacturing device in a next stage, the method comprising:
preparing a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
providing an inlet-side closed end plate and an outlet-side closed end plate in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
providing, in the impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space;
providing, outside the molten metal flow path forming body, a magnetic field device composed of a pair of permanent magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space;
providing the outlet-side electrode in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate; and causing an urging device composed of the electrode device and the magnetic field device to apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and send molten metal on an inner side than the outlet-side electrode through the first gap to the second gap.
preparing a molten metal flow path body having a molten metal flow path for flowing electrically conductive molten metal that has flown from outside toward the metal product manufacturing device;
providing an inlet-side closed end plate and an outlet-side closed end plate in the molten metal flow path body so as to partition a front and a rear of the molten metal flow path and form an impurity removal space;
providing, in the impurity removal space, an electrode device composed of an inlet-side electrode and an outlet-side electrode that face each other in a longitudinal direction in which molten metal flows and can be put into electrical contact with molten metal in the impurity removal space;
providing, outside the molten metal flow path forming body, a magnetic field device composed of a pair of permanent magnets that face each other in a width direction intersecting the longitudinal direction, sandwich the impurity removal space of the molten metal flow path forming body in the width direction, have opposite poles facing each other, and can form a magnetic field in molten metal in the impurity removal space;
providing the outlet-side electrode in a floating state in the impurity removal space so that a first gap opened vertically is formed between the outlet-side electrode and a bottom surface of the molten metal flow path forming body and a second gap opened in the longitudinal direction is formed between the outlet-side electrode and the outlet-side closed end plate; and causing an urging device composed of the electrode device and the magnetic field device to apply a Lorentz force downward to molten metal in the impurity removal space so as to increase a density of the molten metal and cause impurities in the molten metal to rise up to a surface of the molten metal, and send molten metal on an inner side than the outlet-side electrode through the first gap to the second gap.
Applications Claiming Priority (3)
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JP2017220376A JP6526769B1 (en) | 2017-11-15 | 2017-11-15 | Apparatus for removing impurities from molten metal and method for removing impurities |
JP2017-220376 | 2017-11-15 | ||
PCT/JP2018/031232 WO2019097799A1 (en) | 2017-11-15 | 2018-08-23 | Device and method for continuous removal of impurities from molten metal |
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CA3081826A1 true CA3081826A1 (en) | 2019-05-23 |
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CA3081826A Abandoned CA3081826A1 (en) | 2017-11-15 | 2018-08-23 | Device and method for continuously removing impurities from molten metal |
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US (1) | US20200261970A1 (en) |
EP (1) | EP3711878A4 (en) |
JP (1) | JP6526769B1 (en) |
AU (1) | AU2018368019A1 (en) |
CA (1) | CA3081826A1 (en) |
WO (1) | WO2019097799A1 (en) |
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EP4112205A4 (en) * | 2020-02-28 | 2023-11-29 | Kenzo Takahashi | Molten metal purification apparatus |
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RU2753847C1 (en) * | 2020-10-12 | 2021-08-24 | Публичное акционерное общество "Электромеханика" | Method and device for production of metal ingot |
CN113441695B (en) * | 2021-05-24 | 2022-08-26 | 中南大学 | Method for removing non-oriented silicon steel inclusions |
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JPH02122011A (en) * | 1988-10-31 | 1990-05-09 | Daido Steel Co Ltd | Method and apparatus for floating up and separating inclusion |
IL100136A (en) * | 1991-11-24 | 1994-12-29 | Ontec Ltd | Method and device for producing homogeneous alloys |
JPH0647506A (en) * | 1992-07-30 | 1994-02-22 | Kawasaki Steel Corp | Method for cleaning molten metal in tundish and device therefor |
JP2002346709A (en) * | 2001-05-28 | 2002-12-04 | Sumitomo Metal Ind Ltd | Continuous casting tundish, and continuous casting method using the same |
JP4772407B2 (en) * | 2005-07-15 | 2011-09-14 | 高橋 謙三 | Molten metal transfer device |
JP5431438B2 (en) * | 2011-11-10 | 2014-03-05 | 高橋 謙三 | Molding device for continuous casting with stirring device |
JP5815763B2 (en) * | 2014-01-24 | 2015-11-17 | 高橋 謙三 | Permanent magnet type molten metal stirring device, melting furnace having the same, and continuous casting device |
CN107119192B (en) * | 2017-04-17 | 2019-02-22 | 上海大学 | The method and device of electromagnetism vortex driving force purifying molten metal |
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2017
- 2017-11-15 JP JP2017220376A patent/JP6526769B1/en active Active
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2018
- 2018-08-23 CA CA3081826A patent/CA3081826A1/en not_active Abandoned
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- 2018-08-23 EP EP18878774.1A patent/EP3711878A4/en not_active Withdrawn
- 2018-08-23 WO PCT/JP2018/031232 patent/WO2019097799A1/en unknown
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EP4112205A4 (en) * | 2020-02-28 | 2023-11-29 | Kenzo Takahashi | Molten metal purification apparatus |
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EP3711878A4 (en) | 2021-05-12 |
JP2019089112A (en) | 2019-06-13 |
US20200261970A1 (en) | 2020-08-20 |
WO2019097799A1 (en) | 2019-05-23 |
JP6526769B1 (en) | 2019-06-05 |
AU2018368019A1 (en) | 2020-06-04 |
EP3711878A1 (en) | 2020-09-23 |
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