US2438992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Well cementing apparatus
Assignee: Baker Hughes Oilfield Operations LLC
•
Filing: 1942-04-03
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Granted: 1948-04-06
•
Expires: 1962-04-03
Abstract
No abstract record available.
Inventors
- 👤 Roscoe O Childers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:56
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/10; E21B33/13; E21B33/14; E21B33/146
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USRE19570E
Cited
US1866038A
Cited
US2169568A
Cited
US2291371A
Cited
US2295822A
Cited
US2327092A
Cited
US2330267A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-04-06 | 1951-10-06 | 1952-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-04-06 | 1955-10-06 | 1956-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-04-06 | 1959-10-06 | 1960-04-06 | $7700.00 | Window Closed / Lapsed |