Patent US3728109A successfully refreshed from Google Patents.
US3728109A
Expired / Lapsed
US
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Manufacturing method of free-cutting lead steel
Assignee: JFE Engineering Corp
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Filing: 1970-09-29
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Granted: 1973-04-17
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Expires: 1990-09-29
Abstract
Abstract THIS INVENTION RELATES TO A METHOD OF PRODUCING FREECUTTING LEAD STEEL COMPRISING POURING THE MOLTEN STEEL INTO A LADLE, STIRRING THE STEEL BY PASSING THEREINTO A GASEOUS MATERIAL WHICH DOES NOT HARMFULLY AFFECTED THE QUALITY OF THE STEEL, AND FEEDING A WIRE ROD OF LEAD OR A LEAD ALLOY INTO THE MOLTEN STEEL AT AN ADDING VELOCITY OF 1 TO 20 METRES PER SECOND, SAID WIRE ROD HAVING A DIAMETER OF 5-20 MM.
Inventors
- 👤 M Okubo
- 👤 T Kawawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:37
CPC Classifications
C; C21; C21C; C21C7/00; C21C7/0056; C22; C22C; C22C38/00; C22C38/60; C21C7/0006; C21C2007/0012
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |