Downhole probe assembly

• US 20050257629A1
• Filed: 05/20/2005
• Published: 11/24/2005
• Est. Priority Date: 05/21/2004
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Stone, James E., Sherrill, Kristopher V., McGregor, Malcolm Douglas, Gilbert, Gregory N., Sitka, Mark A., Hardin, John R. Jr., Maranuk, Christopher Anthony, Gray, Glenn C.
• Granted Patent: US 7,603,897 B2
• Time in Patent Office: Days
• US Class Current: 73/863.840
• CPC Class Codes: E21B 49/10 using side-wall fluid samplers or testers
• CPC Class Codes: G01N 1/10 in the liquid or fluent state burettes, pipettes B01L3/02; sampling of ground water E02D1/06; metering by volume of fluids or fluent solid material G01F11/00, G01F13/00

Abstract

A downhole, extendable apparatus and methods of use are described and claimed herein. In one embodiment, the extendable apparatus includes a piston that extends toward a borehole wall, the piston having an inner sampling member that is also extendable. The sampling member may be further extended to engage the borehole wall and penetrate the formation. The sampling member may also include a screen and an inner scraper or wiper that frictionally engages the screen and reciprocates to remove debris from the screen. The piston may comprise a seal pad having an internal cavity for receiving a volume of fluid. In another embodiment, the extendable apparatus comprises multiple, concentric pistons for extending the sampling member further toward the borehole wall than is possible with a single piston. The extendable apparatus may also include a retraction contact switch and position indicator.

Claims

1. A downhole apparatus comprising:

a drill collar having an outer surface for interaction with an earth formation;

an extendable sample device recessed beneath said outer surface in a first position to extend beyond said outer surface to a second position;

a sampling member coupled to said extendable sample device, said sampling member having a bore and a sampling end to extend to a position beyond said extendable sample device second position, said bore to receive at least formation fluid from the earth formation.

2. The apparatus of claim 1 further comprising a screen having a bore coupled to said sampling end.

3. The apparatus of claim 2 further comprising:

a scraper reciprocally disposed within said sampling member bore to frictionally engage said screen.

4. The apparatus of claim 1 further comprising a seal pad having an aperture, said seal pad coupled to said extendable sample device, said seal pad to prevent borehole contaminants from entering said sampling member.

5. The apparatus of claim 4 wherein said seal pad is made from a flexible material and further comprises an internal cavity to receive an adjustable volume of fluid, said adjustable volume of fluid comprising at least one of hydraulic fluid, saline solution and silicone gel.

6. The apparatus of claim 5 wherein said volume of fluid comprises an electro-rheological fluid to receive an electrical field.

7. The apparatus of claim 2 wherein said screen comprises at least one of a plurality of slots and a gravel pack.

8. The apparatus of claim 7 wherein a size of said slots and a diameter of said gravel pack particles are adjustable.

9. The apparatus of claim 1 further comprising at least one draw-down cylinder coupled to said extendable sample device to receive at least formation fluid from the earth formation.

10. The apparatus of claim 1 further comprising an equalizer valve coupled to said extendable sample device to receive at least formation fluid from the earth formation.

11. The extendable sample device of claim 1 comprising at least one sleeve having an aperture, each aperture of the at least one sleeve to slidably retain a piston.

20. The apparatus of claim 1 further comprising:

a drill string for drilling a borehole in the earth formation;

a drill bit coupled to a distal end of said drill string; and

wherein said drill collar is coupled to said drill string near said drill bit, said drill collar further comprising a plurality of sensors.

21. The apparatus of claim 20 wherein said drill collar further comprises a stabilizer, and wherein said extendable sample device is mounted in said stabilizer.

12. A downhole apparatus comprising:

a sleeve having a bore;

a first piston having a bore, said first piston being slidingly retained within said sleeve bore between a retracted position and an extended position;

a second piston having a bore, said second piston being slidingly retained within said first piston bore between a retracted position and an extended position; and

a snorkel having a bore, said snorkel being slidingly retained within said second piston bore between a retracted position and an extended position, wherein a portion of said snorkel extends beyond said second piston bore when said snorkel is in said snorkel extended position.

13. The apparatus of claim 12 wherein said snorkel further comprises a screen having a bore.

14. The apparatus of claim 13 further comprising:

a scraper reciprocally disposed within said snorkel bore to frictionally engage said screen.

15. The apparatus of claim 12 further comprising a seal pad having an aperture, said seal pad coupled to said second piston, said seal pad to prevent borehole contaminants from entering said snorkel.

16. The apparatus of claim 15 wherein said seal pad is made from a flexible material and further comprises an internal cavity to receive an adjustable volume of fluid, said adjustable volume of fluid comprising at least one of hydraulic fluid, saline solution and silicone gel.

17. The apparatus of claim 16 wherein said volume of fluid comprises an electro-rheological fluid to receive an electrical field.

18. The apparatus of claim 12 further comprising at least one draw-down cylinder communicating with said snorkel to receive at least formation fluid from an earth formation.

19. The apparatus of claim 12 further comprising an equalizer valve communicating with said snorkel to receive at least formation fluid from an earth formation.

22. A method of sampling a formation comprising:

extending from within a drill collar a first piston radially outward;

extending a snorkel from within the first piston, the snorkel to contact a borehole wall in an earth formation;

removing contaminants from the snorkel;

sealing a volume surrounding the snorkel to prevent contaminants from re-entering the snorkel; and

measuring a property of the formation.

23. The method of claim 22 further comprising:

extending a second piston from within the first piston; and

further extending the snorkel from within the second piston.

24. The method of claim 22 wherein removing contaminants from the snorkel comprises slidably engaging a scraper within the snorkel to remove the contaminants.

25. The method of claim 22 wherein sealing a volume surrounding the snorkel comprises moving a seal pad coupled to any one of the first piston and the snorkel to form a seal with the borehole wall.

26. The method of claim 25 wherein forming a seal with the borehole wall comprises filling a cavity in the seal pad with at least one of hydraulic fluid, saline solution, silicone gel, and an electro-rheological fluid.

27. The method of claim 22 further comprising filtering contaminants adjacent the snorkel.

28. The method of claim 27 wherein filtering contaminants adjacent the snorkel further comprises:

flowing the contaminants over at least one of a plurality of slots in a screen and a gravel pack; and

adjusting at least one of a size of the slots and a diameter of the gravel particles if the formation property differs from a predetermined value.