Patent US4443268A successfully refreshed from Google Patents.
US2805933A
Expired / Lapsed
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Process for the preparation of ferroalloys
Assignee: Knapsack AG
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Filing: 1954-12-15
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Granted: 1957-09-10
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Expires: 1974-12-15
Abstract
No abstract record available.
Inventors
- 👤 Mcyer Oskar
- 👤 Ebert Hans
- 👤 Frank Klaus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:17
CPC Classifications
C; C22; C22C; C22C35/00; C22C35/005
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
140 words
THE PROCESS OF PREPARING A FERROALLOY SELECTED FROM THE GROUP CONSISTING OF FERROCHROMIUM CONTAINING A MAXIMUM CARBON CONTENT OF 0.08% AND FERROMANGANESE CONTAINING A MAXIMUM CARBON CONTENT OF APPROXIMATELY 0.2% COMPRISING THE STEPS OF TREATING, AT A TEMPERATURE ABOVE 1600*C., A MEMBER OF THE GROUP CONSISTING AN IRON-SILICO-ALLOY OF MEDIUM SILICON CONTENT CONTAINING AT LEAST 1% BY WEIGHT OF A REDUCING METAL, AND A MIXTURE OF AN IRON-SILICO-ALLOY OF MEDIUM SILICON CONTENT AND AT LEAST 1% BY WEIGHT OF A REDUCING METAL, SAID REDUCING METAL BEING SELECTED FROM THE GROUP CONSISTING OF ALUMINUM, TITANIUM AND ZIRCONIUM, WITH OXYGEN TO OBTAIN THE DESIRE CARBON CONTENT, REFINING THE RESULTING ALLOY WITH A MIXTURE CONSISTING OF LIME AND AN ORE OF THE SELECTED ALLOYING METAL, SEPARATING RESULTING SLAG AND TREATING RESULTING FERROALLY WITH OXYGEN TO LOWER THE SILICON, NITROGEN AND OTHER IMPURITY CONTENT.
Claim 2
Dependent Claim
140 words
THE PROCESS OF PREPARING A FERROALLOY SELECTED FROM THE GROUP CONSISTING OF FERROCHROMIUM CONTAINING A MAXIMUM CARBON CONTENT OF 0.08% AND FERROMANGANESE CONTAINING A MAXIMUM CARBON CONTENT OF APPROXIMATELY 0.2% COMPRISING THE STEPS OF TREATING, AT A TEMPERATURE ABOVE 1600*C., A MEMBER OF THE GROUP CONSISTING AN IRON-SILICO-ALLOY OF MEDIUM SILICON CONTENT CONTAINING AT LEAST 1% BY WEIGHT OF A REDUCING METAL, AND A MIXTURE OF AN IRON-SILICO-ALLOY OF MEDIUM SILICON CONTENT AND AT LEAST 1% BY WEIGHT OF A REDUCING METAL, SAID REDUCING METAL BEING SELECTED FROM THE GROUP CONSISTING OF ALUMINUM, TITANIUM AND ZIRCONIUM, WITH OXYGEN TO OBTAIN THE DESIRE CARBON CONTENT, REFINING THE RESULTING ALLOY WITH A MIXTURE CONSISTING OF LIME AND AN ORE OF THE SELECTED ALLOYING METAL, SEPARATING RESULTING SLAG AND TREATING RESULTING FERROALLY WITH OXYGEN TO LOWER THE SILICON, NITROGEN AND OTHER IMPURITY CONTENT.
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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) | 1960-09-09 | 1961-03-11 | 1961-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-09-09 | 1965-03-11 | 1965-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-09-09 | 1969-03-11 | 1969-09-10 | $7700.00 | Window Closed / Lapsed |