Method and apparatus for directional drilling

Patent metadata

Field	Value
Publication number	US-RE46090-E
Application number	US-201414279669-A
Country	US
Kind code	E1
Filing date	May 16, 2014
Priority date	Dec 19, 2002
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

A method of and system for directional drilling reduces the friction between the drill string and the well bore. A downhole drilling motor is connected to the surface by a drill string. The drilling motor is oriented at a selected tool face angle. The drill string is rotated at said surface location in a first direction until a first torque magnitude without changing the tool face angle. The drill string is then rotated in the opposite direction until a second torque magnitude is reached, again without changing the tool face angle. The drill string is rocked back and forth between the first and second torque magnitudes.

First claim

What is claimed is:

1. A method of drilling a well, which comprises:
(a) orienting a downhole drilling motor at a selected face angle, said drilling motor being connected by a drill string to a surface drilling location; (b) rotating said drill string at said surface location in a first direction until a first measured torque magnitude is reached at said surface location; and then, (c) rotating said drill string in the direction opposite said first direction until a second measured torque magnitude is reached at said surface location.

2. The method as claimed in claim 1 , including repeating steps (b) and (c) while drilling with said drilling motor.

3. The method as claimed in claim 1 , wherein said second torque magnitude is substantially equal to said first torque magnitude.

4. The method as claimed in claim 1 , wherein said second torque magnitude is less than said first torque magnitude.

5. The method as claimed in claim 1 , wherein:
said drill string is rotated in said first direction to said first torque magnitude without changing said face angle; and, said drill string is rotated in said direction opposite said first direction to said second torque magnitude without changing said face angle.

6. The method as claimed in claim 5 , wherein said second torque magnitude is substantially equal to said first torque magnitude.

7. The method as claimed in claim 5 , wherein said second torque magnitude is less than said first torque magnitude.

8. The method as defined in claim 1 wherein said first torque magnitude is selected so that the drill string is rotated to a selected position therealong.

9. The method as defined in claim 8 wherein the selected position along the drill string is a position at which reactive torque from said drilling motor substantially is stopped by friction between the drill string and a wall of a wellbore.

10. A method of drilling a well, which comprises:
(a) determining the face angle of a downhole drilling motor, said downhole drilling motor being connected to a surface location by a drill string; (b) rotating said drill string at said surface location in a first direction until a first measured torque magnitude is reached at said surface location without changing said face angle; and then (c) rotating said drill string in the direction opposite said first direction until a second measure torque magnitude is reached at said surface location without changing said face angle.

11. The method as claimed in claim 10 , including repeating steps (a) and (b) while drilling with said drilling motor.

12. The method as claimed in claim 10 , wherein said second torque magnitude is substantially equal to said first torque magnitude.

13. The method as claimed in claim 10 , wherein said second torque magnitude is less than said first torque magnitude.

14. A directional drilling system, which comprises:
a torque sensor for determining torque applied to a drill string by rotating means; a controller for operating said rotating means to rotate said drill string in a first direction until a first torque magnitude is determined and then in a direction opposite said first direction until a second torque magnitude is determined.

15. The system as claimed in claim 14 , wherein said second torque magnitude is substantially equal to said first torque magnitude.

16. The system as claimed in claim 14 , wherein said controller operates said rotating means to rotate said drill string until said first and second torque magnitudes are reached without changing bit face angle.

17. The system as claimed in claim 14 further comprising means for calculating a value of said first torque magnitude such that said drill string is rotated to a position along said drill string at which reactive torque from a drilling motor is stopped by friction between the drill string and a wall of a wellbore.

18. The system as claimed in claim 14 , wherein said second torque magnitude is less than said first torque magnitude.

19. The system as claimed in claim 14 , wherein said rotating means comprises a top drive.

20. The system as claimed in claim 14 , wherein said rotating means comprises a rotary table.

21. A method of drilling a well, comprising:
(a) orienting a downhole drilling motor at a selected face angle, said drilling motor being connected by a drill string to a surface location; (b) automatically rotating said drill string at said surface location in a first direction until a first preselected measured torque magnitude is reached at said surface location; and then (c) automatically rotating said drill string in the direction opposite said first direction until a second preselected measured torque magnitude is reached at said surface location.

22. The method as claimed in claim 21, further comprising repeating (b) and (c) while drilling the well with said drilling motor.

23. The method as claimed in claim 21, wherein said second preselected torque magnitude is substantially equal to said first preselected torque magnitude.

24. The method as claimed in claim 21, wherein said second preselected torque magnitude is less than said first preselected torque magnitude.

25. The method as claimed in claim 21, wherein said drill string is automatically rotated in said first direction to said first preselected measured torque magnitude without changing said face angle and said drill string is automatically rotated in said direction opposite said first direction to said second preselected measured torque magnitude without changing said face angle.

26. The method as claimed in claim 25, wherein said second preselected torque magnitude is substantially equal to said first preselected torque magnitude.

27. The method as claimed in claim 25, wherein said second preselected torque magnitude is less than said first preselected torque magnitude.

28. The method as claimed in claim 21 wherein said first preselected torque magnitude is selected so that the drill string is rotated to a selected position therealong.

29. The method as claimed in claim 28 wherein the selected position along the drill string is a position at which reactive torque from said drilling motor is substantially stopped by friction between the drill string and a wall of a wellbore.

Assignees

• Schlumberger Technology Corp

Inventors

• Maidla Eric E
• Haci Marc

Classifications

• E21B44/04

  in response to the torque of the drive {; Measuring drilling torque (E21B44/06 takes precedence; measuring stresses in a well bore pipe E21B47/007)} · CPC title

• E21B7/068 Primary

  drilled by a down-hole drilling motor (down-hole drives per se E21B4/00, E21B7/067 takes precedence) · CPC title

• E21B44/00 Primary

  Automatic control systems specially adapted for drilling operations, i.e. self-operating systems which function to carry out or modify a drilling operation without intervention of a human operator, e.g. computer-controlled drilling systems; Systems specially adapted for monitoring a plurality of drilling variables or conditions · CPC title