Patent US2894291A successfully refreshed from Google Patents.
Patent US3072895A successfully refreshed from Google Patents.
Patent US3424249A successfully refreshed from Google Patents.
US3424249A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cleaning steam injection well tubing string in situ
Assignee: Shell USA Inc
•
Filing: 1966-10-19
•
Granted: 1969-01-28
•
Expires: 1986-10-19
Abstract
No abstract record available.
Inventors
- 👤 Tyler W Hamby Jr
- 👤 Maurice M Patterson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:06
CPC Classifications
E; E21; E21B; E21B36/00; C; C09; C09K; C09K8/00; C09K8/52; C09K8/524; E21B36/003; E21B37/00; E21B43/00; E21B43/16; E21B43/24
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2139595A
Cited
US2704979A
Cited
US2998066A
Cited
US3142336A
Cited
US3080919A
Cited
US3246614A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-01-28 | 1972-07-29 | 1973-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-01-28 | 1976-07-29 | 1977-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-01-28 | 1980-07-29 | 1981-01-28 | $7700.00 | Window Closed / Lapsed |