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US4015673A Expired / Lapsed US ⏱️ 0.0 years remaining

Directional drilling system

Assignee: BP Corp North America Inc
•
Filing: 1976-03-22
•
Granted: 1977-04-05
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Expires: 1996-03-22
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Abstract

Abstract This invention concerns the drilling of boreholes in the earth. It concerns a rotary drilling system having a particular bottom hole assembly (BHA) for use in increasing or decreasing the angle of deviation from the vertical of a borehole. It also teaches a method whereby the angle of deviation can be calculated for each assembly. There is one assembly disclosed for increasing the angle of deviation and another assembly disclosed for decreasing the angle of deviation. Also disclosed is a novel "universal stabilizer" for use in the bottom hole assembly.

Inventors

  • 👤 James T. Craig, Jr.
  • 👤 Arthur Park

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 06:10
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/10; E21B17/1078; E21B47/00; E21B47/02; E21B47/022; E21B7/00; E21B7/04; E21B7/06; E21B7/10

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 162 words
A method of determining if a bottom hole assembly (BHA) is stable for an angle θ O of deviation in which the BHA includes a bit, a centralizer, a lower section of heavy-walled pipe called drill collars having a length X between said bit and said centralizer, which comprises: a. determine the angle θ O , θ O being the angle the centerline of the lower section of heavy-walled pipe makes with the center line of the borehole; b. if the angle θ O is positive, i.e., centerline of the lower section of heavy-walled pipe is above the centerline of the hole, the BHA is stable, proceed to step (e); c. if the angle θ is negative, decrease the length X; d. repeat step (a), if θ O is positive, the BHA is stable; if θ O is not positive, repeat steps (c) and (a) until θ O is positive; e. then using the stable BHA in the drilling of a well.
Claim 2
Independent Claim 162 words
A method of determining if a bottom hole assembly (BHA) is stable for an angle θ O of deviation in which the BHA includes a bit, a centralizer, a lower section of heavy-walled pipe called drill collars having a length X between said bit and said centralizer, which comprises: a. determine the angle θ O , θ O being the angle the centerline of the lower section of heavy-walled pipe makes with the center line of the borehole; b. if the angle θ O is positive, i.e., centerline of the lower section of heavy-walled pipe is above the centerline of the hole, the BHA is stable, proceed to step (e); c. if the angle θ is negative, decrease the length X; d. repeat step (a), if θ O is positive, the BHA is stable; if θ O is not positive, repeat steps (c) and (a) until θ O is positive; e. then using the stable BHA in the drilling of a well.
Claim 3
Dependent Claim 23 words
A method as defined in claim 1, including the step of increasing the weight on said drill string to increase θ O .

References Cited (Backward Citations)

US2646253A Cited
US2646254A Cited
US2829864A Cited
US3229375A Cited
US3799277A Cited
US3878903A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-04-04 1980-10-04 1981-04-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-04-04 1984-10-04 1985-04-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-04-04 1988-10-04 1989-04-05 $7700.00 Window Closed / Lapsed

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