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US1857616A
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Hydraulic underreamer
Assignee: Baker Hughes Oilfield Operations LLC
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Filing: 1931-02-03
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Granted: 1932-05-10
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Expires: 1951-02-03
Abstract
No abstract record available.
Inventors
- 👤 Reuben C Baker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:06
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/26; E21B10/32; E21B10/322
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) | 1935-05-10 | 1935-11-09 | 1936-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-05-10 | 1939-11-09 | 1940-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-05-10 | 1943-11-09 | 1944-05-10 | $7700.00 | Window Closed / Lapsed |