US3835230A
Expired / Lapsed
US
⏱️ 0.0 years remaining
D.c. arc furnace for steelmaking
Assignee: NIPKTI CHERNA METALURGIA
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Filing: 1973-08-01
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Granted: 1974-09-10
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Expires: 1993-08-01
Abstract
Abstract A system for producing steel comprises a d-c arc furnace having at least one water-cooled anode connectable to the d-c source and effective after melting has progressed to generate an arc between the melt and a cathode juxtaposed therewith. A melting anode is connectable to the d-c source initially and is pressed against the mass to be melted for the initial melting and is movable to follow the decrease in level of this mass as the melting progresses. Switches disconnect the melting anode and connect the process anode to the source.
Inventors
- 👤 V Peev
- 👤 V Velev
- 👤 A Valchev
- 👤 E Ninov
- 👤 G Visokomogilski
- 👤 Y Krestenyakov
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:28
CPC Classifications
H; H05; H05B; H05B7/00; H05B7/005; C; C21; C21C; C21C5/00; C21C5/52; C21C5/5229; F; F27; F27D; F27D11/00; F27D11/08; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
235 words
An apparatus for making steel by an arc process, comprising: a furnace having a hearth and a substantially closed top provided with at least one opening; a carbon cathode extending through said opening and provided with means enabling displacement of said carbon cathode relative to said hearth; a water-cooled process anode received in said furnace at a level above the bottom of said hearth and adapted to contact a melt of steel upon the formation thereof; at least one melting anode movably extending into said furnace and provided with means for pressing said melting anode against a mass of ferrous material in said furnace on said hearth and enabling said melting anode to follow the decrease in level of said material upon the smelting thereof; a direct-current source having a negative terminal connected to said cathode; first switch means between the positive terminal of said source and said melting anode for initially connecting said melting anode with said source whereby electric current flows through said material between said cathode and said melting anode to smelt said material and form a pool of molten steel on said hearth; and second switch means between said positive terminal and said process anode and operable alternately with said first switch means for connecting said process anode to said source to enable an electric current to pass through the pool of molten steel between said process anode and said cathode.
Claim 2
Independent Claim
235 words
An apparatus for making steel by an arc process, comprising: a furnace having a hearth and a substantially closed top provided with at least one opening; a carbon cathode extending through said opening and provided with means enabling displacement of said carbon cathode relative to said hearth; a water-cooled process anode received in said furnace at a level above the bottom of said hearth and adapted to contact a melt of steel upon the formation thereof; at least one melting anode movably extending into said furnace and provided with means for pressing said melting anode against a mass of ferrous material in said furnace on said hearth and enabling said melting anode to follow the decrease in level of said material upon the smelting thereof; a direct-current source having a negative terminal connected to said cathode; first switch means between the positive terminal of said source and said melting anode for initially connecting said melting anode with said source whereby electric current flows through said material between said cathode and said melting anode to smelt said material and form a pool of molten steel on said hearth; and second switch means between said positive terminal and said process anode and operable alternately with said first switch means for connecting said process anode to said source to enable an electric current to pass through the pool of molten steel between said process anode and said cathode.
Claim 3
Dependent Claim
39 words
The apparatus defined in claim 1 wherein said furnace has a door with a sill and said process electrode is built into a wall of said furnace at a location below said sill and is fixed in said wall.
Claim 4
Dependent Claim
21 words
The apparatus defined in claim 1 wherein said process anode has a water-cooled portion received in a wall of said furnace.
Claim 5
Dependent Claim
45 words
The apparatus defined in claim 1 wherein said furnace has a door with a sill, said process anode being movably mounted in a wall of said furnace and having a lower end disposed below said sill in a fully inserted position of said process anode.
Claim 6
Dependent Claim
23 words
The apparatus defined in claim 1 wherein said furnace has a shell, further comprising means for electrically insulating said anodes from said shell.
Claim 7
Dependent Claim
26 words
The apparatus defined in claim 1 wherein said furnace has a shell and said anodes are connected in parallel and are electrically connected with said shell.
Claim 8
Dependent Claim
18 words
The apparatus defined in claim 1 wherein said cathode has a protective coating preventing oxidation of its flanks.
Claim 9
Dependent Claim
22 words
The apparatus defined in claim 1 wherein said melting anode is composed of carbon and has a protective coating along its flanks.
References Cited (Backward Citations)
US3439103A
Cited
US3651238A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-09 | 1978-03-11 | 1978-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-09 | 1982-03-11 | 1982-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-09 | 1986-03-11 | 1986-09-10 | $7700.00 | Window Closed / Lapsed |