US3456734A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Protection of well casing from thermal overstressing
Assignee: Phillips Petroleum Co
•
Filing: 1968-01-05
•
Granted: 1969-07-22
•
Expires: 1988-01-05
Abstract
No abstract record available.
Inventors
- 👤 Maurice R Dean
- 👤 Joseph C Trantham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:02
CPC Classifications
E; E21; E21B; E21B36/00; E21B36/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1237139A
Cited
US3042114A
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US3142336A
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US3180411A
Cited
US3280909A
Cited
US3358759A
Cited
US3386512A
Cited
US3380530A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-07-21 | 1973-01-20 | 1973-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-07-21 | 1977-01-20 | 1977-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-07-21 | 1981-01-20 | 1981-07-22 | $7700.00 | Window Closed / Lapsed |