Waveform anti-stick slip system and method

Patent metadata

Field	Value
Publication number	US-9650880-B2
Application number	US-201414244556-A
Country	US
Kind code	B2
Filing date	Apr 3, 2014
Priority date	Apr 12, 2013
Publication date	May 16, 2017
Grant date	May 16, 2017

Abstract

The present disclosure is directed to systems and methods for rotating a drill string to overcome issues related to static friction during drilling. An embodiment includes a drive system configured to rotate the drill string through variable angular displacements and at variable rotation speeds based on control signals received by the drive system, and a control system configured transmit the control signals to the drive system, wherein the control system is configured to generate the control signals based on pipe characteristics within the drill string and friction values associated with the drill string to establish a rotation pattern of the drive system to approach a desired effective reach of surface torque generated by the drive system on the drill string.

First claim

The invention claimed is:

1. A system for rotating a drill string, comprising:
a drive system configured to rotate the drill string through variable angular displacements and at variable rotation speeds based on control signals received by the drive system; and
a control system configured transmit the control signals to the drive system, wherein the control system is configured to generate the control signals based on pipe characteristics within the drill string and static friction values along the drill string to establish a rotation pattern of the drive system to approach a desired effective reach of surface torque generated by the drive system on the drill string, wherein the control system is configured to generate the control signals to comprise a velocity profile along which the drive system rotates the drill string, and wherein the velocity profile comprises a series of target rotational velocities over a time period, such that the drive system follows the velocity profile to facilitate propagation of a waveform to the desired effective reach along the drill string.

2. The system of claim 1 , wherein the drive system comprises a top drive configured to rotate a quill of the top drive based on the control signals.

3. The system of claim 1 , wherein the control system is configured to calculate the desired effective reach based on a user-defined buffer region between a surface torque and a reactive torque generated by a mud motor at a bottom of the drill string.

4. The system of claim 1 , wherein the pipe characteristics comprise user-provided, measured, or predetermined inputs of a number of pipe sections, inclination values of the pipe sections, azimuth values of the pipe sections, and pipe physical measures.

5. The system of claim 4 , wherein the pipe physical measures comprise pipe diameter, pipe weight, and pipe length.

6. The system of claim 1 , wherein the control system is configured to generate control signals instructing the drive system to rotate through an initial percentage of the series of target rotational velocities at a first rate and through a remaining percentage of the series of target rotational velocities at a second rate that is lower than the first rate.

7. The system of claim 1 , wherein the control system is configured to generate control signals with an initial target for the series of target rotational velocities and configured to change the initial target to a secondary target for the series of target rotational velocities based on updated data from one or more sensors during rotation of the drill string.

8. The system of claim 7 , comprising the one or more sensors disposed on a downhole portion of the drill string and configured to measure at least torque.

9. The system of claim 1 , comprising one or more sensors configured to measure a rotational velocity of the drill string.

10. The system of claim 9 , wherein the drive system comprises a top drive and the one or more sensors comprise a sensor configured to measure a rotational velocity of a quill of the top drive.

11. The system of claim 1 , wherein the control system is configured to predefine the velocity profile by calculating the velocity profile or selecting the velocity profile from a lookup table based on input data, and the series of target rotational velocities are determined from the velocity profile having been predefined.

12. The system of claim 11 , wherein the input data is received from sensors and/or user inputs.

13. A method of rotating a drill string, comprising:
sending a velocity profile from a controller to a drive system, wherein the velocity profile comprises a series of target rotational velocities over a time period, wherein the drive system is configured to follow the velocity profile;
measuring one or more rotational velocities along a drill string coupled with the drive system via a rotational feature; and
controlling the rotational feature of the drive system based on comparing the one or more rotational velocities and the target rotational velocities to facilitate propagation of a waveform through the drill string.

14. The method of claim 13 , comprising defining the target rotational velocities based on pipe characteristics within the drill string and static friction values along the drill string to approach a desired effective reach of surface torque generated via the velocity profile.

15. The method of claim 13 , comprising modifying the series of target rotational velocities during operation based on updated measurements acquired from a tool face sensor of a bottom hole assembly on the drill string.

16. The method of claim 13 , comprising averaging the one or more rotational velocities to define an average measured rotational velocity and controlling the rotational feature based on a comparison of the average measured rotational velocity and the target rotational velocities at times in the time period.

17. The method of claim 13 , wherein measuring the one or more rotational velocities along the drill string comprises measuring a rotational velocity of the rotational feature.

18. The method of claim 17 , wherein measuring the rotational velocity of the rotational feature comprises measuring a rotational velocity of a quill of a top drive.

19. The method of claim 16 , comprising determining the target rotational velocities based on positional information of a downhole tool and characteristics of the drill string such that an orientation of a downhole portion of the drill string beyond a designated point or an orientation of the downhole tool is not changed.

20. A control system, comprising:
an automation controller including a processor and a memory configured to supply a drive system for rotating a drill string with rotational data based on input data that includes a desired effective reach of surface torque along the drill string from the drive system, wherein the rotational data defines rotational velocities of different directions and magnitudes to facilitate overcoming static friction associated with contact between a drill string and a wellbore, and wherein the rotational data comprises a velocity profile comprising rotational velocities of different directions and magnitudes over a time period, and wherein the drive system is configured to rotate the drill string along the velocity profile; and
a display visualization configured to provide a graphic bar indicative of a measured value of the surface torque on the drill string in an upper portion of the graphic bar, a neutral torque area in a middle portion of the graphic bar, and a measured value of reactive torque on the drill string in a lower portion of the graphic bar.

21. The control system of claim 20 , wherein the rotational data is configured to generate a wave that propagates through the drill string to the extent defined by the desired effective reach.

22. The control system of claim 20 , comprising a top drive incorporating the automation controller.

23. The control system of claim 20 , comprising sensors for detecting propagation of a wave through the drill string.

Assignees

• Tesco Corp

Inventors

• Bowley Ryan Thomas
• Greening Doug Christian

Classifications

• 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

• E21B3/02

  Surface drives for rotary drilling · CPC title

• E21B44/04 Primary

  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

• E21B3/022

  Top drives · CPC title