Frequency Analysis of Drilling Signals

• US 20160245067A1
• Filed: 10/23/2014
• Published: 08/25/2016
• Est. Priority Date: 10/28/2013
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (SLB)
• Original Assignee: Schlumberger Technology Corporation (SLB)
• Inventors: Quezada, Arturo, Haci, Marc, Ringer, Maurice
• Granted Patent: US 10,487,642 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: E21B 3/022 Top drives
• CPC Class Codes: E21B 4/02 Fluid rotary type drives
• CPC Class Codes: E21B 44/04 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 Class Codes: E21B 47/007 Measuring stresses in a pipe string or casing for locating blocked portions of pipes E21B47/09
• CPC Class Codes: E21B 47/02 Determining slope or direction
• CPC Class Codes: E21B 7/04 Directional drilling
• CPC Class Codes: E21B 7/062 the tool shaft rotating inside a non-rotating guide travelling with the shaft E21B7/067 and E21B7/068 take precedence

Abstract

A method for directional drilling a subterranean borehole includes transforming surface sensor measurements from time domain sensor data to frequency domain sensor data. A rotary drilling parameter may be changed when a parameter of the frequency domain sensor data reaches a threshold or is within a predetermined range of values.

Claims

1. A method for directional drilling a subterranean borehole, the method comprising:

(a) rotary drilling the subterranean borehole;

(b) receiving surface sensor measurements while rotary drilling in (a);

(c) transforming the surface sensor measurements from time domain sensor data to frequency domain sensor data; and

(d) changing a rotary drilling parameter when a parameter of the frequency domain sensor data reaches a threshold or is within a predetermined range of values.

2. The method of claim 1, wherein rotary drilling in (a) comprises:

(i) deploying a drilling string in the borehole, the drill string including a plurality of interconnected sections of drill pipe and a bottom hole assembly including a drilling motor and a drill bit, the drilling motor including a bent housing along its axis;

(ii) circulating drilling fluid through the drill string thereby causing the drilling motor to rotate the drill bit relative to the drill string; and

(iii) rotating the drill string from a surface location.

3. The method of claim 1, wherein the sensor measurements comprise at least one of surface torque measurements, axial force measurements, and standpipe pressure measurements.

4. The method of claim 1, wherein the sensor measurements are transformed in (c) using at least one of a Fourier transform, a Laplace transform, and a Z-transform.

5. The method of claim 1, wherein the parameter of the frequency domain sensor data comprises at least one of an amplitude and a phase at a particular frequency.

6. The method of claim 1, wherein (d) comprises changing at least one of a rotation rate of the drill string, a weight on bit, and a drilling fluid flow rate.

7. The method of claim 1, wherein the surface sensor measurements comprise surface torque measurements and the rotary drilling parameter changed in (d) comprises a drill string rotation rate.

8. The method of claim 1, wherein the surface sensor measurements comprise axial force measurements and the rotary drilling parameter changed in (d) comprises at least one of a drill string rotation rate and a weight on bit.

9. The method of claim 1, wherein the surface sensor measurements comprise standpipe pressure measurements and the rotary drilling parameter changed in (d) comprises a drilling fluid flow rate.

10. A method for directional drilling a subterranean borehole, the method comprising:

(a) deploying a drilling string in the borehole, the drill string including a plurality of interconnected sections of drill pipe and a bottom hole assembly including a drilling motor and a drill bit, the drilling motor including a bent housing along its axis;

(b) circulating drilling fluid through the drill string thereby causing the drilling motor to rotate the drill bit relative to the drill string;

(c) rotary drilling the borehole via rotating the drill string from a surface location;

(d) receiving surface torque measurements while rotary drilling in (c);

(e) transforming the surface torque measurements from time domain torque data to a frequency domain torque data; and

(f) changing a rotation rate of the drill string when a parameter of the frequency domain torque data reaches a threshold or is within a predetermined range of values.

11. The method of claim 10, wherein the surface torque measurements are transformed in (e) using at least one of a Fourier transform, a Laplace transform, and a Z-transform.

12. The method of claim 10, wherein the parameter of the frequency domain torque data comprises at least one of an amplitude and a phase at a particular frequency.

13. The method of claim 12, wherein the drill string is rotated at a first high rotation rate when the phase at the particular frequency is in a first predetermined range of values and a second low rotation rate when the phase at the particular frequency is in a second predetermined range of values.

14. The method of claim 12, wherein the drill string is rotated at a first high rotation rate when the phase at the particular frequency is outside of a predetermined range of values and a second low rotation rate when the phase at the particular frequency is inside the predetermined range of values.

15. The method of claim 12, further comprising correlating the phase at the particular frequency with a toolface angle of the bent housing.

16. A method for directional drilling a subterranean borehole, the method comprising:

(a) deploying a drilling string in the borehole, the drill string including a plurality of interconnected sections of drill pipe and a bottom hole assembly including a drilling motor and a drill bit, the drilling motor including a bent housing along its axis;

(b) circulating drilling fluid through the drill string thereby causing the drilling motor to rotate the drill bit relative to the drill string;

(c) rotary drilling the borehole via rotating the drill string from a surface location;

(d) receiving surface torque measurements while rotary drilling in (c);

(e) transforming the surface torque measurements from a time domain to a frequency domain to obtain a phase at a particular frequency; and

(f) alternating back and forth between a first high drill string rotation rate and a second low drill string rotation rate while rotary drilling in (c), rotary drilling at the first rotation rate when the phase is within a first predetermined range of values and at the second rotation rate when the phase is within a second predetermined range of values.

17. The method of claim 16, wherein the surface torque measurements are transformed in (e) using a Fast Fourier Transform.

18. A method for directional drilling a subterranean borehole, the method comprising:

(a) deploying a drilling string in the borehole, the drill string including a plurality of interconnected sections of drill pipe and a bottom hole assembly including a drilling motor and a drill bit, the drilling motor including a bent housing along its axis;

(b) circulating drilling fluid through the drill string thereby causing the drilling motor to rotate the drill bit relative to the drill string;

(c) rotary drilling the borehole via rotating the drill string from a surface location;

(d) receiving axial force measurements while rotary drilling in (c);

(e) transforming the axial force measurements from time domain axial force data to frequency domain axial force data; and

(f) changing at least one of a rotation rate of the drill string and a weight on bit when at least one parameter of the frequency domain axial force data reaches a threshold or is within a predetermined range of values.

19. The method of claim 18, wherein at least one of the rotation rate of the drill string and the weight on bit are changed in (f) when an amplitude of the axial force exceeds a predetermined threshold within a predetermined range of frequencies.