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US2675353A Expired / Lapsed US ⏱️ 0.0 years remaining

Oil base drilling fluid

Assignee: Shell Development Co
•
Filing: 1950-10-20
•
Granted: 1954-04-13
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Expires: 1970-10-20
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Abstract

No abstract record available.

Inventors

  • 👤 Reginald D Dawson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 02:26
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/32

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 79 words
AN OIL-CONTAINING DRILLING FLUID FOR WELLS, COMPRISING A SUBSTANTIAL QUANTITY OF A MINERAL OIL, A FINELY DIVIDED SOLID MATERIAL DISPERSED IN SAID FLUID FOR WEIGHTING SAID FLUID TO AT LEAST 75 LBS. PER CU. FT., AND A MINOR AMOUNT OF A TETRAALKYL AMMONIUM HALIDE HAVING AT LEAST ONE OF THE ALKYL RADICALS WITH A CHAIN LENGTH OF AT LEAST 12 CARBON ATOMS, SAID MINOR AMOUNT BEING SUFFICIENT TO STABILIZE THE DRILLING FLUID AND MAINTAIN IT AT A DRILLING VISCOSITY.
Claim 2
Dependent Claim 79 words
AN OIL-CONTAINING DRILLING FLUID FOR WELLS, COMPRISING A SUBSTANTIAL QUANTITY OF A MINERAL OIL, A FINELY DIVIDED SOLID MATERIAL DISPERSED IN SAID FLUID FOR WEIGHTING SAID FLUID TO AT LEAST 75 LBS. PER CU. FT., AND A MINOR AMOUNT OF A TETRAALKYL AMMONIUM HALIDE HAVING AT LEAST ONE OF THE ALKYL RADICALS WITH A CHAIN LENGTH OF AT LEAST 12 CARBON ATOMS, SAID MINOR AMOUNT BEING SUFFICIENT TO STABILIZE THE DRILLING FLUID AND MAINTAIN IT AT A DRILLING VISCOSITY.

References Cited (Backward Citations)

US2099825A Cited
US2265759A Cited
US2350154A Cited
US2461483A Cited
US2531812A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1957-04-12 1957-10-12 1958-04-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1961-04-12 1961-10-12 1962-04-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1965-04-12 1965-10-12 1966-04-13 $7700.00 Window Closed / Lapsed

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