Patent US4473124A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4473124A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for operating rotary drilling under conditions of high cuttings transport efficiency

Assignee: Mobil Oil AS
•
Filing: 1983-05-02
•
Granted: 1984-09-25
•
Expires: 2003-05-02
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In a rotary method of drilling a well into the earth employing a drilling mud system, the transport ratio (hole cleaning efficiency) is increased by increasing the yield point to plastic viscosity ratio of the drilling fluid while maintaining the plastic viscosity constant. In a preferred embodiment, the plastic viscosity is varied within the range of 7.5 to 30 centipoises and the yield point to plastic viscosity ratio is varied within the range of 0.20 to 1.5.

Inventors

  • 👤 Joseph G. Savins

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 22:02
CPC Classifications
E; E21; E21B; E21B21/00; E21B21/08

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 78 words
A method of drilling a well into the earth wherein a drill string is located in said well and an active drilling fluid system is employed in the circulation of drilling fluid between the surface of the earth and the bottom of the well, the improvement comprising employing a drilling fluid exhibiting plastic flow maintained at a constant plastic viscosity and increasing the ratio of yield point to plastic viscosity within a predetermined range thereby increasing transport ratio.
Claim 2
Independent Claim 78 words
A method of drilling a well into the earth wherein a drill string is located in said well and an active drilling fluid system is employed in the circulation of drilling fluid between the surface of the earth and the bottom of the well, the improvement comprising employing a drilling fluid exhibiting plastic flow maintained at a constant plastic viscosity and increasing the ratio of yield point to plastic viscosity within a predetermined range thereby increasing transport ratio.
Claim 3
Dependent Claim 33 words
The method of claim 1 wherein the plastic viscosity is maintained within the range of 15 to 30 centipoises and the yield point to plastic viscosity ratio is increased from 0.20 to 1.5.
Claim 4
Independent Claim 114 words
A method of drilling a well into the earth wherein a drill string is located in said well and an active drilling fluid system is employed in the circulation of drilling fluid into said drill string and upwardly through the annular space between the drill string and the wall of the well, said well being drilled under laminar flow conditions with a wide annulus in a highly deviated wellbore, the improvement comprising employing a drilling fluid exhibiting plastic flow maintained at a plastic viscosity of about 15 centipoises and increasing the yield point to plastic viscosity ratio from about 0.4 to about 1.5 thereby increasing the transport ratio from about 25% to about 40%.
Claim 5
Independent Claim 114 words
A method of drilling a well into the earth wherein a drill string is located in said well and an active drilling fluid system is employed in the circulation of drilling fluid into said drill string and upwardly through the annular space between the drill string and the wall of the well, said well being drilled under laminar flow conditions with a wide annulus in a highly deviated wellbore, the improvement comprising employing a drilling fluid exhibiting plastic flow maintained at a plastic viscosity of about 15 centipoises and increasing the yield point to plastic viscosity ratio from about 0.4 to about 1.5 thereby increasing the transport ratio from about 25% to about 40%.
Claim 6
Independent Claim 114 words
A method of drilling a well into the earth wherein a drill string is located in said well and an active drilling fluid system is employed in the circulation of drilling fluid into said drill string and upwardly through the annular space between the drill string and the wall of the well, said well being drilled under laminar flow conditions with a narrow annulus in a highly deviated wellbore, the improvement comprising employing a drilling fluid exhibiting plastic flow maintained at a plastic viscosity of about 30 centipoises and increasing the yield point to plastic viscosity ratio from about 0.5 to about 1.5 thereby increasing the transport ratio from about 25% to about 40%.
Claim 7
Independent Claim 114 words
A method of drilling a well into the earth wherein a drill string is located in said well and an active drilling fluid system is employed in the circulation of drilling fluid into said drill string and upwardly through the annular space between the drill string and the wall of the well, said well being drilled under laminar flow conditions with a narrow annulus in a highly deviated wellbore, the improvement comprising employing a drilling fluid exhibiting plastic flow maintained at a plastic viscosity of about 30 centipoises and increasing the yield point to plastic viscosity ratio from about 0.5 to about 1.5 thereby increasing the transport ratio from about 25% to about 40%.

References Cited (Backward Citations)

US3637492A Cited
US3878110A Cited
US3860070A Cited
US3985659A Cited
US4330414A Cited
US4322301A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-09-25 1988-03-26 1988-09-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-09-25 1992-03-26 1992-09-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-09-25 1996-03-26 1996-09-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag