Patent US3868987A successfully refreshed from Google Patents.
US3868987A
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Method of electric refining of metals by slag, known as the E. S. R. method, using liquefied gas to isolate the slag and electrode from the ambient air
Assignee: Air Liquide SA
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Filing: 1973-02-12
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Granted: 1975-03-04
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Expires: 1993-02-12
Abstract
Abstract High purity metal is produced by electro-slag refining by passing an electric current through a consumable electrode of the material to be refined, then through an electrically conductive slag to a body of the molten metal atop an upwardly growing water-cooled ingot. The lower end of the electrode and the surface of the slag are protected by a layer of liquefied gas substantially inert to the electrode, e.g. argon or nitrogen, the vaporized gas passing off to the atmosphere after a portion thereof is directed against an upper portion of the electrode.
Inventors
- 👤 Jean G Galey
- 👤 Gerard Bentz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:02
CPC Classifications
B; B22; B22D; B22D23/00; B22D23/06; B22D23/10; C; C22; C22B; C22B9/00; C22B9/16; C22B9/18
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
143 words
A METHOD OF PRODUCING A HIGH PURITY METAL BY ELECTROSLAG REFINING AT ATMOSPHERIC PRESSURE, COMPRISING PASSING IN ELECTRICAL CURRENT BETWEEN A CONSUMABLE ELECTRODE OF THE MATERIAL TO BE REFINED AND A MASS OF ALREADY REFINED METAL THROUGH A MOLTEN AND ELECTRICALLY CONDUCTIVE SLAG, AND POURING A LIQUEFIED GAS IN LIQUID PHASE, WHICH IS SUBSTANTIALLY INERT TO SAID METAL, DOWNWARDLY ALONG AT LEAST THE LOWER PART OF THE ELECTRODE TO FORM A FILM OVER AT LEAST THE LOWER PART OF THE ELECTRODE WHICH ISOLATES SAID LOWER PART OF THE ELECTRODE FROM THE AMBIENT AIR AND THEN OVER THE UPPER SURFACE OF THE SLAG THEREBY TO FORM A LIQUID LAYER ON SAID SLAG FROM WHICH IT IS SEPARATED BY A CONTINUOUS LAYER OF VAPOR ISOLATING SAID SLAG FROM THE AMBIENT AIR, THE FLOW RATE OF SAID LIQUEFIED GAS BEING SUFFICIENT TO FORM SAID LIQUID LAYER.
Claim 2
Independent Claim
143 words
A METHOD OF PRODUCING A HIGH PURITY METAL BY ELECTROSLAG REFINING AT ATMOSPHERIC PRESSURE, COMPRISING PASSING IN ELECTRICAL CURRENT BETWEEN A CONSUMABLE ELECTRODE OF THE MATERIAL TO BE REFINED AND A MASS OF ALREADY REFINED METAL THROUGH A MOLTEN AND ELECTRICALLY CONDUCTIVE SLAG, AND POURING A LIQUEFIED GAS IN LIQUID PHASE, WHICH IS SUBSTANTIALLY INERT TO SAID METAL, DOWNWARDLY ALONG AT LEAST THE LOWER PART OF THE ELECTRODE TO FORM A FILM OVER AT LEAST THE LOWER PART OF THE ELECTRODE WHICH ISOLATES SAID LOWER PART OF THE ELECTRODE FROM THE AMBIENT AIR AND THEN OVER THE UPPER SURFACE OF THE SLAG THEREBY TO FORM A LIQUID LAYER ON SAID SLAG FROM WHICH IT IS SEPARATED BY A CONTINUOUS LAYER OF VAPOR ISOLATING SAID SLAG FROM THE AMBIENT AIR, THE FLOW RATE OF SAID LIQUEFIED GAS BEING SUFFICIENT TO FORM SAID LIQUID LAYER.
Claim 3
Dependent Claim
22 words
A method as claimed in claim 1, and projecting vaporized gas from said liquefied gas onto said electrode above said liquid layer.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-03 | 1978-09-02 | 1979-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-03 | 1982-09-02 | 1983-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-03 | 1986-09-02 | 1987-03-04 | $7700.00 | Window Closed / Lapsed |