Patent US1572793A successfully refreshed from Google Patents.
Patent US2797988A successfully refreshed from Google Patents.
US2797988A
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Process of producing metal alloys of low impurity content
Assignee: PITTSBURGH METALLURG Co I
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Filing: 1956-01-18
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Granted: 1957-07-02
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Expires: 1976-01-18
Abstract
No abstract record available.
Inventors
- 👤 Jr John S Barker
- 👤 Norris B Mcfarlane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:47
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/003
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
56 words
THE PROCESS OF PRODUCING A FERROSILICON ALLOY WITH A LOW IMPURITY CONTENT WHICH COMPRISES HEATING THE FERROSILICON IN AN ARC FURNACE TO A MOLTEN STATE,DELIVERING THE MOLTEN MASS INTO AN ARC FURNACE HAVING AN ACID LINING AND ADDING SAND AND LIME TO THE MASS IN THE FURNACE TO FORM A CALCIUM SILICATE OVER THE MOLTEN ALLOY.
Claim 2
Dependent Claim
56 words
THE PROCESS OF PRODUCING A FERROSILICON ALLOY WITH A LOW IMPURITY CONTENT WHICH COMPRISES HEATING THE FERROSILICON IN AN ARC FURNACE TO A MOLTEN STATE,DELIVERING THE MOLTEN MASS INTO AN ARC FURNACE HAVING AN ACID LINING AND ADDING SAND AND LIME TO THE MASS IN THE FURNACE TO FORM A CALCIUM SILICATE OVER THE MOLTEN ALLOY.
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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) | 1960-07-01 | 1960-12-31 | 1961-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-01 | 1964-12-31 | 1965-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-01 | 1968-12-31 | 1969-07-02 | $7700.00 | Window Closed / Lapsed |