METHOD AND APPARATUS FOR FORMATION TESTING

• US 20080015781A1
• Filed: 07/12/2007
• Published: 01/17/2008
• Est. Priority Date: 07/12/2006
• Status: Active Grant

• Current Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Original Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Inventors: Niemeyer, Eick, Kischkat, Tobias, Meister, Matthias
• Granted Patent: US 7,729,861 B2
• Time in Patent Office: Days
• US Class Current: 702/11
• CPC Class Codes: E21B 49/008 by injection test; by analysing pressure variations in an injection or production test, e.g. for estimating the skin factor measuring pressure E21B47/06
• CPC Class Codes: E21B 49/10 using side-wall fluid samplers or testers
• CPC Class Codes: G01V 11/00 Prospecting or detecting by methods combining techniques covered by two or more of main groups G01V1/00 - G01V9/00

Abstract

A method for conducting a formation test includes providing a volume change model for a tool component, and providing a control program that uses the volume change model to estimate a system volume change resulting from a change in the tool component during a downhole operation. An apparatus for conducting a formation test includes a carrier, a formation test tool, a measurement device that estimates a change in a tool component during operation, and a processor that uses a volume change model to estimate a system volume change resulting at least in part from the change in the tool component during a downhole operation.

Claims

1. A method for conducting a formation test comprising:

providing a volume change model for a tool component; and

providing a control program that uses the volume change model to estimate a system volume change resulting from a change in the tool component during a downhole operation.

2. The method of claim 1 further comprising storing one or more of the volume change model and the control program on a computer-readable medium.

3. The method of claim 2 further comprising disposing the computer readable medium in a formation test sub.

4. The method of claim 1, wherein the volume change model comprises a seal model, the seal model relating a system volume change to seal deformation.

5. The method of claim 1, wherein the volume change model comprises a probe model, the probe model relating a system volume change to probe movement.

6. The method of claim 1, wherein the volume change model comprises a combination of a seal model and a probe model, the seal model and probe model relating a system volume change to respective seal deformation and probe movement.

7. The method of claim 3, wherein disposing the computer readable medium in a formation test sub comprises disposing the computer readable medium in one or more of a wireline formation test sub and a while-drilling formation test sub.

8. An apparatus for conducting a formation test comprising:

a carrier conveyable into a well borehole;

a formation test tool coupled to the carrier, the formation test tool including a tool component;

a measurement device that estimates a change in the tool component during operation; and

a processor that uses a volume change model to estimate a system volume change resulting at least in part from the change in the tool component during a downhole operation.

9. The apparatus of claim 8 further comprising a controller that controls a test operation using the estimated system volume change.

10. The apparatus of claim 8, wherein the tool component comprises an extendable formation fluid sampling probe, the estimated tool component change being an extension of the formation fluid sampling probe.

11. The apparatus of claim 8, wherein the tool component comprises a seal that engages a subterranean formation, the estimated tool component change being a deformation of the seal.

12. The apparatus of claim 8, wherein the formation test tool comprises an extendable formation fluid sampling probe having a seal member disposed on a distal end of the formation fluid sampling probe, the estimated tool component change being an extension of the formation fluid sampling probe in combination with a deformation of the seal.

13. The apparatus of claim 8, wherein the formation test tool comprises an extendable formation fluid sampling probe having a seal disposed on a distal end of the formation fluid sampling probe, the measurement device measuring one or more of i) a distance relating to an extension of the formation fluid sampling probe, ii) a force exerted on the seal, and iii) a hydraulic pressure used to extend the formation fluid sampling probe.

14. The apparatus of claim 9, wherein the controller controls one or more of a formation fluid draw pump and a probe extension pump.

15. The apparatus of claim 8, wherein the carrier comprises at least one of a drill pipe, a wired pipe, a coil tube, and a wireline.

16. A method for conducting a formation test comprising:

conveying a tool component into a well borehole;

contacting a subterranean formation with a the tool component to establish fluidic communication with the subterranean formation;

conducting a formation test operation; and

estimating a volume change using a volume change model that relates a tool component change to a volume change.

17. The method of claim 16, wherein the tool component includes a seal that contacts the subterranean formation, the volume change model comprises a seal model, the seal model relating a system volume change to seal deformation.

18. The method of claim 16, wherein the tool component includes a probe having a seal at a distal end for contacting the subterranean formation, the volume change model comprising a probe model relating a system volume change to probe movement.

19. The method of claim 16, wherein the tool component includes a probe having a seal at a distal end for contacting the subterranean formation, the volume change model comprising a combination of a seal model and a probe model, the seal model and probe model relating a system volume change to respective seal deformation and probe movement.

20. The method of claim 16, wherein conveying a tool component into a well borehole comprises using one or more of a drill pipe, a wired pipe, a coil tube, and a wireline.

21. The method of claim 16 further comprising controlling a test parameter based at least in part on the estimated system volume change.

22. The method of claim 16 further comprising estimating a correction factor for correcting formation test information, the correction factor being based at least in part on the estimated system volume change.

23. The method of claim 16 further comprising controlling a test parameter and estimating a correction factor for correcting formation test information, the controlling and the correction factor being based at least in part on the estimated system volume change.

24. The method of claim 16, wherein the volume change model comprises an estimated response of a seal member material to a downhole parameter.

25. The method of claim 24, wherein the downhole parameter comprises one or more of i) a distance relating to an extension of the seal member ii) a force exerted on the seal member, and iii) a hydraulic pressure used to extend the seal member for contacting the subterranean formation.

26. The method of claim 21, wherein controlling the test parameter includes controlling one or more of a formation fluid draw pump and a probe extension pump.