Patent US2518795A successfully refreshed from Google Patents.
US2518795A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Valve for drill stems and the like
Assignee: Hydril LLC
•
Filing: 1946-11-16
•
Granted: 1950-08-15
•
Expires: 1966-11-16
Abstract
No abstract record available.
Inventors
- 👤 Granville S Knox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:11
CPC Classifications
E; E21; E21B; E21B23/00; E21B23/004; E21B23/006; E21B21/00; E21B21/10; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7904; Y10T137/7922; Y10T137/7929
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1953-08-14 | 1954-02-13 | 1954-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-14 | 1958-02-13 | 1958-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-14 | 1962-02-13 | 1962-08-15 | $7700.00 | Window Closed / Lapsed |