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US4681627A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for preparing an ingot from metal scrap

Assignee: Mitsubishi Metal Corp
•
Filing: 1986-05-27
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Granted: 1987-07-21
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Expires: 2006-05-27
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Abstract

Abstract A process for producing an ingot from molten metal scrap, particularly scrap consisting of refractory metals such as titanium, zirconium and alloys thereof, comprises changing ungraded metal scrap into a tubular member with a closed end which is made of the same material as that of the metal scrap; melting the scrap-charged tubular member by heating which an electron beam or plasma electron beam, with said member being held substantially horizontally in a vacuum melting furnace. Alternatively, a pair of consumable electrodes which are made of such scrap-charged tubular members are melted with an arc produced between the tips of the tubular members which serve as electrodes. Since the metal scrap need not be graded according to size, the range of scrap charges that can be melted for ingot making is expanded. If the tubular member is replaced by a box with an open top, the scrap can be packed easily and uniformly. This provides improved melting efficiency and a greater ease of melting operations since, in vacuum melting with an electron beam or plasma electron beam, a constant melting rate is attained and, in arc melting using one or more pairs of the scrap-charged boxes as consumable electrodes, a consistent arc can be maintained between the tips of each of the two scrap-charged boxes which serve as electrodes.

Inventors

  • 👤 Yoshiharu Mae
  • 👤 Tsutomu Oka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 10:27
CPC Classifications
C; C22; C22B; C22B9/00; C22B9/16; C22B9/22; C22B9/226; C22B34/00; C22B34/10; C22B34/12; C22B34/1295; C22B34/14; C22B7/00; C22B7/001; C22B7/003; C22B9/04; C22B9/20; C22B9/228; Y; Y02; Y02P; Y02P10/00; Y02P10/20

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 133 words
A process for producing an ingot from metal scrap by first melting the scrap in a vacuum melting furnace and then solidifying the melt in a water-cooled mold into an ingot comprising: charging the metal scrap into a tubular member with a closed end and another end, said tubular member being made of the same material as that of the scrap; heating said tubular member with an electron beam or from said closed end toward the other end thereof to heat and melt said tubular member and said scrap charged into said tubular member to form a melt; said tubular member being held substantially horizontally in said vacuum melting furnace during said heating step; and a causing the resulting melt to drop into said water-cooled mold wherein it is solidified into an ingot.
Claim 2
Dependent Claim 133 words
A process for producing an ingot from metal scrap by first melting the scrap in a vacuum melting furnace and then solidifying the melt in a water-cooled mold into an ingot comprising: charging the metal scrap into a tubular member with a closed end and another end, said tubular member being made of the same material as that of the scrap; heating said tubular member with an electron beam or from said closed end toward the other end thereof to heat and melt said tubular member and said scrap charged into said tubular member to form a melt; said tubular member being held substantially horizontally in said vacuum melting furnace during said heating step; and a causing the resulting melt to drop into said water-cooled mold wherein it is solidified into an ingot.
Claim 3
Dependent Claim 18 words
The process of claim 1, wherein said metal scrap is made of titanium, zirconium or an alloy thereof.
Claim 4
Dependent Claim 16 words
The process of claim 1, wherein said tubular member is heated with a plasma electron beam.
Claim 5
Dependent Claim 24 words
The process of claim 1, comprising temporarily holding said melt within a hearth, and overflowing said melt from said hearth into said water-cooled mold.
Claim 6
Dependent Claim 13 words
The process of claim 4, comprising heating said hearth with said melt therein.
Claim 7
Dependent Claim 14 words
The process of claim 5, wherein said hearth is heated with an electron beam.
Claim 8
Dependent Claim 29 words
The process of claim: 1, wherein said heating step comprises advancing said tubular member toward a heating zone of said electron beam during said heating of said tubular member.
Claim 9
Dependent Claim 23 words
The process of claim 7, wherein said advancing step comprises incrementally advancing said tubular member into said heating zone during said heating thereof.
Claim 10
Dependent Claim 154 words
A process for producing an ingot from metal scrap by first melting the scrap in a consumable-electrode type arc melting furnace and then solidifying the melt in a water-cooled mold into an ingot comprising: charging the metal scrap into at least one pair of tubular members each having a closed end and another end, said tubular members being made of the same material as that of the scrap; said at least one pair of tubular members being held substantially horizontally in said furnace and being arranged end-to-end with said closed ends facing each other and spaced apart from each other; producing an arc between said facing closed ends of said tubular members which serve as consumable electrodes in said furnace to heat and melt said tubular members and said scrap charged therein to form a melt; and causing the resulting melt to drop into said water-cooled mold wherein it is solidified into an ingot.
Claim 11
Dependent Claim 154 words
A process for producing an ingot from metal scrap by first melting the scrap in a consumable-electrode type arc melting furnace and then solidifying the melt in a water-cooled mold into an ingot comprising: charging the metal scrap into at least one pair of tubular members each having a closed end and another end, said tubular members being made of the same material as that of the scrap; said at least one pair of tubular members being held substantially horizontally in said furnace and being arranged end-to-end with said closed ends facing each other and spaced apart from each other; producing an arc between said facing closed ends of said tubular members which serve as consumable electrodes in said furnace to heat and melt said tubular members and said scrap charged therein to form a melt; and causing the resulting melt to drop into said water-cooled mold wherein it is solidified into an ingot.
Claim 12
Dependent Claim 18 words
The process df claim 9, wherein said metal scrap is made of titanium, zirconium or an alloy thereof.
Claim 13
Dependent Claim 24 words
The process of claim 9, comprising temporarily holding said melt within a hearth, and overflowing said melt from said hearth into said water-cooled mold.
Claim 14
Dependent Claim 13 words
The process of claim 11, comprising heating said hearth with said melt therein.
Claim 15
Dependent Claim 20 words
The process of claim 9, comprising advancing said tubular members toward each other during said heating thereof by said arc.
Claim 16
Dependent Claim 155 words
A process for producing an ingot from metal scrap by first melting the scrap in a vacuum melting furnace and then solidifying the melt in a water-cooled mold into an ingot comprising: charging the metal scrap into a box with having an open top and at least two ends, said box containing at least one of the components present in said metal scrap, and said box having a shape such as that which is formed by cutting a tubular member of a polygonal cross section in the axial direction; heating said box with an electron beam from an end thereof toward the other end thereof to heat and melt the box and the scrap charged into said box to form a melt; said box being held substantially horizontally in said vacuum melting furnace during said heating step; and causing the resulting melt to drop into said water-cooled mdold wherein it is solidified into an ingot.
Claim 17
Dependent Claim 155 words
A process for producing an ingot from metal scrap by first melting the scrap in a vacuum melting furnace and then solidifying the melt in a water-cooled mold into an ingot comprising: charging the metal scrap into a box with having an open top and at least two ends, said box containing at least one of the components present in said metal scrap, and said box having a shape such as that which is formed by cutting a tubular member of a polygonal cross section in the axial direction; heating said box with an electron beam from an end thereof toward the other end thereof to heat and melt the box and the scrap charged into said box to form a melt; said box being held substantially horizontally in said vacuum melting furnace during said heating step; and causing the resulting melt to drop into said water-cooled mdold wherein it is solidified into an ingot.
Claim 18
Dependent Claim 18 words
The process of claim 14, wherein said metal scrap is made of titanium, zirconium or an alloy thereof.
Claim 19
Dependent Claim 15 words
The process of claim 14, wherein said box is heated with a plasma electron beam.
Claim 20
Dependent Claim 24 words
The process of claim 14, comprising temporarily holding said melt within a hearth, and overflowing said melt from said hearth into said water-cooled mold,
Claim 21
Dependent Claim 13 words
The process of claim 17, comprising heating said hearth with said melt therein.
Claim 22
Dependent Claim 20 words
The process of claim 14, wherein said box has a holding member at at least one of said ends thereof.
Claim 23
Dependent Claim 16 words
The process of claim 14, wherein said box has no holding member at any end thereof.
Claim 24
Dependent Claim 14 words
The process of claim 14, wherein said box has a generally U-shaped cross section.
Claim 25
Dependent Claim 27 words
The process of claim 14, wherein said heating step comprises advancing said box toward a heating zone of said electron beam during said heating of said box.
Claim 26
Dependent Claim 22 words
The process of claim 22, wherein said advancing step comprises incrementally advancing said box into said heating zone during said heating thereof.
Claim 27
Dependent Claim 177 words
A process for producing an ingot from metal scrap by first melting the scrap in a consumable-electrode type arc melting furnace and then solidifying the melt in a water-cooled mold into an ingot comprising: charging the metal scrap into at least one pair of boxes each having an open top and at least two ends said boxes containing at least one of the components present in said metal scrap, and said boxes each having a shape such as that which is formed by cutting a tubular member of a polygonal cross section in the axial direction; said at least one pair of boxes being held substantially horzontally in said furnace and being arranged end-to-end with ends thereof facing each other and spaced apart from each other; producing an arc between said facing ends of said boxes which serve as consumable electrodes in said furnace to heat and melt said boxes and said scrap charged therein to form a melt; and causing the resulting melt to drop into said water-cooled mold wherein it is solidified into an ingot.
Claim 28
Dependent Claim 177 words
A process for producing an ingot from metal scrap by first melting the scrap in a consumable-electrode type arc melting furnace and then solidifying the melt in a water-cooled mold into an ingot comprising: charging the metal scrap into at least one pair of boxes each having an open top and at least two ends said boxes containing at least one of the components present in said metal scrap, and said boxes each having a shape such as that which is formed by cutting a tubular member of a polygonal cross section in the axial direction; said at least one pair of boxes being held substantially horzontally in said furnace and being arranged end-to-end with ends thereof facing each other and spaced apart from each other; producing an arc between said facing ends of said boxes which serve as consumable electrodes in said furnace to heat and melt said boxes and said scrap charged therein to form a melt; and causing the resulting melt to drop into said water-cooled mold wherein it is solidified into an ingot.
Claim 29
Dependent Claim 17 words
The process of claim 24, said metal scrap is made of titanium, zirconium or an alloy thereof.
Claim 30
Dependent Claim 24 words
The process of claim 24, comprising temporarily holding said melt within a hearth, and overflowing said melt from said hearth into said water-cooled mold.
Claim 31
Dependent Claim 13 words
The process of claim 26, comprising heating said hearth with said melt therein.
Claim 32
Dependent Claim 19 words
The process df claim 24, comprising advancing said boxes toward each other during said heating thereof by said arc.
Claim 33
Dependent Claim 18 words
The process of claim 24, wherein said boxes have a holding member at at least one end thereof.
Claim 34
Dependent Claim 15 words
The process of claim 24, wherein said boxes each have a generally U-shaped cross section.

References Cited (Backward Citations)

US2753262A Cited
US2867895A Cited
US2898672A Cited
GB1219099A Cited
US3773499A Cited
US4130416A Cited
US4190404A Cited
GB2049513A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-07-20 1991-01-19 1991-07-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-07-20 1995-01-19 1995-07-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-07-20 1999-01-19 1999-07-21 $7700.00 Window Closed / Lapsed

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