OPERATIONAL CONTROL OF WELLSITE PUMPING UNIT WITH DISPLACEMENT DETERMINATION

• US 20170146007A1
• Filed: 01/08/2016
• Published: 05/25/2017
• Est. Priority Date: 11/20/2015
• Status: Abandoned Application

• Current Assignee: Weatherford Technology Holdings, LLC (Weatherford International PLC)
• Original Assignee: Weatherford Technology Holdings, LLC (Weatherford International PLC)
• Inventors: ROBISON, Clark E., TRAPANI, James S., Thomas, Benson
• Application Number:
  US14/991,253
• Publication Number:
  US 20170146007A1
• Time in Patent Office: Days
• CPC Class Codes: E21B 33/06 Blow-out preventers , i.e. apparatus closing around a drill pipe, e.g. annular blow-out preventers rotating blow-out preventers E21B33/085
• CPC Class Codes: E21B 43/126 Adaptations of down-hole pump systems powered by drives outside the borehole, e.g. by a rotary or oscillating drive powered by fluid E21B43/129
• CPC Class Codes: F04B 19/22 of reciprocating-piston type
• CPC Class Codes: F04B 2203/0209 Rotational speed
• CPC Class Codes: F04B 2203/0903 Position of the driving piston
• CPC Class Codes: F04B 47/02 the driving mechanisms being situated at ground level F04B47/12 takes precedence
• CPC Class Codes: F04B 49/12 by varying the length of stroke of the working members
• CPC Class Codes: F04B 49/20 by changing the driving speed
• CPC Class Codes: F04B 49/22 by means of valves F04B49/03 takes precedence
• CPC Class Codes: F04B 53/16 Casings; Cylinders; Cylinder liners or heads; Fluid connections
• CPC Class Codes: F04B 9/103 having only one pumping chamber

Abstract

A well pumping system can include an actuator that reciprocably displaces a rod string, a flowmeter that measures flow of a fluid between a power source and the actuator, and a control system that modifies reciprocal displacement of the rod string by the actuator, in response to an output of the flowmeter. A well pumping method can include reciprocably displacing a rod string, continuously determining a velocity profile of the rod string, and modifying the velocity profile while the rod string reciprocably displaces, in response to an output of a flowmeter. Another well pumping method can include reciprocably displacing a rod string with an actuator, continuously determining displacement in response to an output of a flowmeter, and modifying reciprocating displacement of the rod string by the actuator, in response to the output of the flowmeter.

Claims

1. A well pumping system, comprising:

an actuator that reciprocably displaces a rod string;

a flowmeter that measures flow of a fluid between a power source and the actuator; and

a control system that modifies reciprocal displacement of the rod string by the actuator, in response to an output of the flowmeter.

2. The well pumping system of claim 1, further comprising at least one discrete position sensor that detects when a member of the actuator or an upper end of the rod string is at a predetermined position.

3. The well pumping system of claim 1, wherein the control system modifies a stroke extent of a member of the actuator, in response to the output of the flowmeter.

4. The well pumping system of claim 1, wherein the control system modifies a stroke extent of the rod string at surface, in response to the output of the flowmeter.

5. The well pumping system of claim 1, wherein the control system modifies a stroke extent of the rod string proximate a downhole pump, in response to the output of the flowmeter.

6. The well pumping system of claim 1, wherein the control system maintains a preselected velocity profile of a member of the actuator, in response to the output of the flowmeter.

7. The well pumping system of claim 1, wherein the control system maintains a preselected velocity profile of the rod string at surface, in response to the output of the flowmeter.

8. The well pumping system of claim 1, wherein the control system maintains a preselected velocity profile of the rod string proximate a downhole pump, in response to the output of the flowmeter.

9. A well pumping method, comprising:

reciprocably displacing a rod string;

continuously determining a velocity profile of the rod string; and

modifying the velocity profile while the rod string reciprocably displaces, in response to an output of a flowmeter.

10. The well pumping method of claim 9, wherein the modifying comprises changing a duration of the velocity profile.

11. The well pumping method of claim 10, wherein the changing is performed while the rod string reciprocably displaces.

12. The well pumping method of claim 9, wherein the modifying comprises changing a position at which an actuator member velocity is zero, the position being determined based on the output of the flowmeter.

13. The well pumping method of claim 12, wherein the changing is performed while the rod string reciprocably displaces.

14. The well pumping method of claim 9, wherein the modifying comprises changing a position at which the rod string velocity is zero at a downhole pump.

15. The well pumping method of claim 14, wherein the changing comprises solving a wave equation in the rod string.

16. The well pumping method of claim 9, wherein the modifying comprises minimizing differences between the detected velocity profile and a preselected velocity profile.

17. The well pumping method of claim 9, wherein the modifying comprises maintaining acceleration of the rod string less than a preselected level.

18. A well pumping method, comprising:

reciprocably displacing a rod string with an actuator;

continuously determining displacement in response to an output of a flowmeter; and

modifying reciprocating displacement of the rod string by the actuator, in response to the output of the flowmeter.

19. The well pumping method of claim 18, wherein the determined displacement is calibrated in response to an output of at least one discrete position sensor.

20. The well pumping method of claim 18, wherein the modifying comprises varying a periodic energy input to the actuator relative to the reciprocating displacement of the rod string.

21. The well pumping method of claim 20, wherein the varying comprises varying a duration of the energy input.

22. The well pumping method of claim 20, wherein the varying comprises varying a level of the energy input.

23. The well pumping method of claim 18, wherein the modifying comprises varying a stroke extent.

24. The well pumping method of claim 23, wherein the varying comprises displacing the stroke extent until either:

a) the stroke extent is positioned at a preselected stroke extent, or

b) the stroke extent has displaced a preselected distance.

25. The well pumping method of claim 18, wherein the modifying comprises modifying a stroke extent of the rod string at surface.

26. The well pumping method of claim 18, wherein the modifying comprises modifying a stroke extent of the rod string proximate a downhole pump.

27. The well pumping method of claim 26, wherein modifying the stroke extent of the rod string proximate the downhole pump comprises solving a wave equation in the rod string.

28. The well pumping method of claim 18, wherein the modifying comprises maintaining a preselected velocity profile of a member of the actuator.

29. The well pumping method of claim 18, wherein the modifying comprises maintaining a preselected velocity profile of the rod string at surface.

30. The well pumping method of claim 18, wherein the modifying comprises maintaining a preselected velocity profile of the rod string proximate a downhole pump.

31. The well pumping method of claim 30, wherein maintaining the preselected velocity profile of the rod string proximate the downhole pump comprises solving a wave equation in the rod string.

32. The well pumping method of claim 18, wherein the modifying comprises maintaining a preselected velocity profile, during the reciprocating displacement of the rod string.