US2925781A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Corrosion prevention
Assignee: Union Oil Company of California
•
Filing: 1957-10-21
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Granted: 1960-02-23
•
Expires: 1977-10-21
Abstract
No abstract record available.
Inventors
- 👤 Paul W Fischer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:24
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/10; C23F11/16; C23F11/162; Y; Y10; Y10S; Y10S507/00; Y10S507/939
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
84 words
IN THE OPERATION OF A PRODUCING OIL WELL WHEREIN A NORMALLY CORROSIVE LIQUID WELL EFFLUENT IS PUMPED FROM THE WELL TO THE EARTH''S SURFACE BY MEANS OF A SUBSURFACE PUMP WHICH IS DRIVEN BY AN HYDRAULIC FLUID SUPPLIED THERETO FROM THE EARTH''S SURFACE UNDER PRESSURE AND A PORTION OF SAID WELL EFFLUENT IS EMPLOYED AS SAID HYDRAULIC FLUID, THE IMPROVEMENT WHICH CONSISTS IN ADMIXING WITH SAID PORTION OF WELL EFFLUENT A CORROSION-INHIBITING AND LUBRICITY-INCREASING AMOUNT OF A SUBSTITUTED THIOUREA COMPOUND HAVING THE GENERAL FORMULA
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) | 1963-02-22 | 1963-08-24 | 1964-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-02-22 | 1967-08-24 | 1968-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-02-22 | 1971-08-24 | 1972-02-23 | $7700.00 | Window Closed / Lapsed |