Patent US3634235A successfully refreshed from Google Patents.
US3634235A
Expired / Lapsed
US
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Drilling fluid and method of use
Assignee: Hughes Tool Co
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Filing: 1967-12-21
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Granted: 1972-01-11
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Expires: 1987-12-21
Abstract
Abstract PRE-TEATMENT OR POST-TREATMENT OF OIL BASE DRILLING FLUIDS FOR OIL WELL APPLICATIONS FOR PURPOSES OF STABILIZING THE FLUID AGANINST DETERIORATION UPON CONTAMINATION WITH WATER BASE DRILLING FLUIDS, WITH OR WITHOUT CLAY SOLIDS, IS EFFECTED BY ADDING TO THE OIL BASE FLUID AN AMPHOTERIC SURFACE-ACTIVE AGENT CONTAINING BOTH ANIONIC AND CATIONIC SURFACE-ACTIVE GROUPS. EXEMPLARY COMPOUNDS WHICH ARE EXTREMELY EFFECTIVE SUFACE-ACTIVE AGENTS IN THE FUNCTION ARE AMINES AND BETAINES WHICH CONTAIN ONE OR MORE CARBOXYL OR CARBOXYLATE GROUPS. ENHANCED EFFECTS ARE ALSO AVAILABLE EMPLOYING SUCH AMPHOTERIC COMPOUNDS WITH SUFONATE TYPE ANINIC SURFACE-ACTIVE AGENTS.
Inventors
- 👤 Doyne L Wilson
- 👤 Robert B Bennett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:13
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/32; Y; Y10; Y10S; Y10S507/00; Y10S507/91
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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |