Patent US2800449A successfully refreshed from Google Patents.
US2800449A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drilling fluids for oil wells and additives therefor
Assignee: Marathon Corp
•
Filing: 1954-03-17
•
Granted: 1957-07-23
•
Expires: 1974-03-17
Abstract
No abstract record available.
Inventors
- 👤 William C Browning
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:09
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/26; C09K8/28; C09K8/14; C09K8/18; C09K8/20; C09K8/203
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
A DRILLING FLUID COMPRISING A BASE FLUID CONSISTING OF A BRINE SOLUTION HAVING AT LEAST 20% BY WEIGHT OF SODIUM CHLORIDE AND ABOUT 1 TO ABOUT 10% BY WEIGHT OF SODIUM LIGHOSULFONATE DISSOLVED THERIN, AND FINELY DIVIDED INSOLUBLE NON-SWELLING CALCIUM SALT UNIFORMLY DISTRBUSTED THEREIN IN AMOUNT OF ABOUT 1% TO ABOUT 25% BY WEIGHT OF THE LIGONSULFONATE, SAID BASE FLUID HAVING A PH OF AT LEAST 9.
Claim 2
Dependent Claim
67 words
A DRILLING FLUID COMPRISING A BASE FLUID CONSISTING OF A BRINE SOLUTION HAVING AT LEAST 20% BY WEIGHT OF SODIUM CHLORIDE AND ABOUT 1 TO ABOUT 10% BY WEIGHT OF SODIUM LIGHOSULFONATE DISSOLVED THERIN, AND FINELY DIVIDED INSOLUBLE NON-SWELLING CALCIUM SALT UNIFORMLY DISTRBUSTED THEREIN IN AMOUNT OF ABOUT 1% TO ABOUT 25% BY WEIGHT OF THE LIGONSULFONATE, SAID BASE FLUID HAVING A PH OF AT LEAST 9.
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) | 1960-07-22 | 1961-01-21 | 1961-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-22 | 1965-01-21 | 1965-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-22 | 1969-01-21 | 1969-07-23 | $7700.00 | Window Closed / Lapsed |