Patent US3437356A successfully refreshed from Google Patents.
US3437356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Casing hanger and seal assembly
Assignee: RECTOR WELL EQUIPMENT CO Inc
•
Filing: 1967-05-01
•
Granted: 1969-04-08
•
Expires: 1987-05-01
Abstract
No abstract record available.
Inventors
- 👤 William L Todd
- 👤 Bobby L Ferguson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:58
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/02; E21B33/03; E21B33/04; E21B33/0422; F; F16; F16L; F16L7/00; F16L7/02
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US144997A
Cited
US2432592A
Cited
US2532662A
Cited
US2712455A
Cited
US2709094A
Cited
US2824757A
Cited
US3334923A
Cited
US3305249A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-04-07 | 1972-10-07 | 1973-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-04-07 | 1976-10-07 | 1977-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-04-07 | 1980-10-07 | 1981-04-08 | $7700.00 | Window Closed / Lapsed |