Patent US3379409A successfully refreshed from Google Patents.
US3379409A
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Composite stopper rod sleeve with insulating inner portion
Assignee: AP Green Refractories Co
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Filing: 1964-11-04
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Granted: 1968-04-23
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Expires: 1984-11-04
Abstract
No abstract record available.
Inventors
- 👤 William D Fitzpatrick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:41
CPC Classifications
F; F27; F27D; F27D3/00; F27D3/15; F27D3/1509; F27D3/1536; B; B22; B22D; B22D41/00; B22D41/14; B22D41/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
66 words
A SLEEVE SEGMENT FOR A STOPPER ROD OF A POURING LADLE COMPRISING A CYLINDRICAL OUTER PORTION OF HIGH REFRACTORY MATERIAL HAVING A THERMAL CONDUCTIVITY OF ABOUT 10 TO ABOUT 18 B.T.U./HR./SQ. FT./*F. DIFFERENCE FOR ONE INCH THICKNESS, AND A CYLINDRICAL INNER PORTION OF INSULATING REFRACTORY HAVING A THERMAL CONDUCTIVITY OF ABOUT 2 TO ABOUT 4 B.T.U./HR./SQ.FT./*F. DIFFERENCE FOR ONE INCH THICKNESS, BONDED TO THE OUTER PORTION.
Claim 2
Dependent Claim
66 words
A SLEEVE SEGMENT FOR A STOPPER ROD OF A POURING LADLE COMPRISING A CYLINDRICAL OUTER PORTION OF HIGH REFRACTORY MATERIAL HAVING A THERMAL CONDUCTIVITY OF ABOUT 10 TO ABOUT 18 B.T.U./HR./SQ. FT./*F. DIFFERENCE FOR ONE INCH THICKNESS, AND A CYLINDRICAL INNER PORTION OF INSULATING REFRACTORY HAVING A THERMAL CONDUCTIVITY OF ABOUT 2 TO ABOUT 4 B.T.U./HR./SQ.FT./*F. DIFFERENCE FOR ONE INCH THICKNESS, BONDED TO THE OUTER PORTION.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-04-23 | 1971-10-23 | 1972-04-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-04-23 | 1975-10-23 | 1976-04-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-04-23 | 1979-10-23 | 1980-04-23 | $7700.00 | Window Closed / Lapsed |