Method and apparatus for rescaling measurements while drilling in different environments

• US 20050155794A1
• Filed: 05/06/2004
• Published: 07/21/2005
• Est. Priority Date: 07/10/2003
• Status: Active Grant

• Current Assignee: Gyrodata Incorporated
• Original Assignee: Gyrodata Incorporated
• Inventors: Wright, Eric, Brosnahan, James Frederick, Neubauer, Greg Allen
• Granted Patent: US 7,234,539 B2
• Time in Patent Office: Days
• US Class Current: 175/45
• CPC Class Codes: E21B 47/024 of devices in the borehole determining slope or direction of the borehole E21B47/022

Abstract

A method and apparatus are provided for determining an orientation of a drilling tool of a drilling system configured to drill a borehole into the Earth'"'"'s surface. The method includes providing a survey system including at least one sensor within the drilling system. The sensor is configured to provide orientation information. The survey system is operable at a plurality of resolution levels. The method further includes operating the survey system at a first resolution level while the drilling tool is a first distance relative to the surface. The method further includes operating the survey system at a second resolution level while the drilling tool is a second distance relative to the surface. The second distance is larger than the first distance. The second resolution level is higher than the first resolution level.

Claims

1. A method for determining an orientation of a drilling tool of a drilling system configured to drill a borehole into the Earth'"'"'s surface, the method comprising:

providing a survey system comprising at least one sensor within the drilling system, the sensor configured to provide orientation information, the survey system operable at a plurality of resolution levels;

operating the survey system at a first resolution level while the drilling tool is a first distance relative to the surface; and

operating the survey system at a second resolution level while the drilling tool is a second distance relative to the surface, the second distance larger than the first distance, the second resolution level higher than the first resolution level.

2. The method of claim 1, wherein the sensor comprises a gyroscopic sensor.

3. The method of claim 2, wherein the first resolution level has a corresponding range of rotation rate measurements of approximately zero to approximately 3600 degrees/hour.

4. The method of claim 3, wherein the second resolution level has a corresponding range of rotation rate measurements of approximately zero to approximately 15 degrees/hour.

5. The method of claim 3, wherein the second resolution level has a corresponding range of rotation rate measurements of approximately zero to approximately 200 degrees/hour.

6. The method of claim 1, further comprising operating the survey system at a third resolution level while the drilling tool is a third distance relative to the surface, the third distance larger than the second distance, the third resolution level higher than the second resolution level.

7. The method of claim 6, wherein the sensor comprises a gyroscopic sensor, the first resolution level has a corresponding range of rotation rate measurements of approximately zero to approximately 3600 degrees/hour, the second resolution level has a corresponding range of rotation rate measurements of approximately zero to approximately 200 degrees/hour, and the third resolution level has a corresponding range of rotation rate measurements of approximately zero to approximately 15 degrees/hour.

8. The method of claim 1, wherein the method further comprises monitoring a linear depth of the drilling tool down the borehole, and changing from the first resolution level to the second resolution level when the linear depth is approximately equal to a predetermined value.

9. The method of claim 1, wherein the method further comprises monitoring a depth of the borehole, and changing from the first resolution level to the second resolution level when the depth of the borehole is approximately equal to a predetermined value.

10. The method of claim 1, wherein the method further comprises monitoring an inclination angle of the drilling tool, and changing from the first resolution level to the second resolution level when the inclination angle is approximately equal to a predetermined value.

11. The method of claim 1, wherein the method further comprises monitoring a change of an inclination angle of the drilling tool as the drilling tool progresses down the borehole, and changing from the first resolution level to the second resolution level when the change of the inclination angle is approximately equal to a predetermined value.

12. The method of claim 1, further comprising changing from the first resolution level to the second resolution level in response to user input.

13. The method of claim 1, further comprising changing from the first resolution level to the second resolution level in response to a data signal from the sensor.

14. The method of claim 13, wherein changing from the first resolution level to the second resolution level is performed in response to noise on the data signal from the sensor.

15. The method of claim 13, wherein changing from the first resolution level to the second resolution level is performed once a magnitude of the data signal does not saturate a corresponding data word.

16. A method for determining a location of a drilling tool of a drilling system configured to drill a borehole into the Earth'"'"'s surface, the method comprising:

providing a survey system comprising at least one sensor within the drilling system, the sensor configured to provide location information, the survey system operable at a plurality of resolution levels;

operating the survey system at a first resolution level while the drilling tool is a first distance relative to the surface; and

operating the survey system at a second resolution level while the drilling tool is a second distance relative to the surface, the second distance larger than the first distance, the second resolution level higher than the first resolution level.

17. The method of claim 16, wherein the sensor comprises a gyroscopic sensor.

18. The method of claim 16, further comprising operating the survey system at a third resolution level while the drilling tool is a third distance relative to the surface, the third distance larger than the second distance, the third resolution level higher than the second resolution level.

19. A method for determining either an orientation or a location of a drilling tool of a drilling system configured to drill a borehole into the Earth'"'"'s surface, the method comprising:

providing a survey system comprising at least one sensor within the drilling system, the sensor configured to provide orientation information, the survey system operable at a plurality of resolution levels;

operating the survey system at a first resolution level while the drilling tool is at a first location relative to the surface;

operating the survey system at a second resolution level while the drilling tool is at a second location relative to the surface, the second location farther from the surface than is the first location, the second resolution level higher than the first resolution level; and

calculating the orientation or the location of the drilling tool using the orientation information.

20. The method of claim 19, wherein the sensor comprises a gyroscopic sensor.

21. The method of claim 19, further comprising operating the survey system at a third resolution level while the drilling tool is at a third location relative to the surface, the third location farther from the surface than is the second location, the third resolution level higher than the second resolution level.

22. A method of operating a sensor of a system for drilling a borehole, the method comprising:

configuring the sensor to provide orientation information having a first resolution level while at a first position relative to a-surface location; and

configuring the sensor to provide orientation information having a second resolution level higher than the first resolution level while at a second position relative to the surface location.

23. The method of claim 22, wherein the surface location is a surface opening location of the borehole.

24. The method of claim 22, wherein the first position and the second position are both above the surface location and the second position is closer to the surface location than is the first position.

25. The method of claim 22, wherein the first position is above the surface location and the second position is below the surface location.

26. The method of claim 22, wherein the first position and the second position are both below the surface location and the second position is farther from the surface location than is the first position.

27. The method of claim 22, wherein the sensor comprises a gyroscopic sensor.

28. The method of claim 22, further comprising changing from the first resolution level to the second resolution level in response to user input.

29. The method of claim 22, further comprising changing from the first resolution level to the second resolution level in response to a data signal from the sensor.

30. The method of claim 22, further comprising configuring the sensor to provide orientation information having a third resolution level higher than the second resolution level while at a third position relative to the surface location.

31. The method of claim 30, wherein the second position and the third position are both below the surface location and the third position is further below the surface borehole location than is the second position.

32. A method of operating a sensor of a drilling system comprising a drill string, the method comprising:

configuring the sensor to provide orientation information having a first resolution level while the drill string has a length less than a predetermined length; and

configuring the sensor to provide orientation information having a second resolution level higher than the first resolution level while the drill string has a length greater than the predetermined length.

33. A drilling system for drilling a borehole into the Earth'"'"'s surface, the system comprising:

a drilling tool; and

a survey system configured to be operable at a plurality of resolution levels, the survey system comprising;

at least one sensor within the drilling system, the sensor configured to provide orientation information; and

a controller coupled to the sensor, the controller configured to operate at a first resolution level while the drilling tool is a first distance relative to the surface and to operate at a second resolution level while the drilling tool is a second distance relative to the surface, the second distance larger than the first distance, the second resolution level higher than the first resolution level.

34. The drilling system of claim 33, wherein the controller comprises a microprocessor within the drilling system.