Downhole measurement assembly, tool and method

Patent metadata

Field	Value
Publication number	US-9771790-B2
Application number	US-201314383531-A
Country	US
Kind code	B2
Filing date	Feb 20, 2013
Priority date	Mar 16, 2012
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

A downhole measurement assembly, tool, and method is provided. The downhole measurement assembly includes at least one drill collar 220 having at least one compensation portion and at least one force portion with a load path 239 therethrough. The compensation portion has a different dimension from the force portion. The assembly also includes a plurality of compensation sensors 230.1, 230.2 positionable about the compensation portion to measure downhole tool pressures applied thereto, and a plurality of force sensors 230.3, 230.4 positionable about the force portion to measure downhole forces applied thereto. The compensation sensors and the force sensors are positionable about the drill collar(s) 220 in a strain configuration along the load path 239 whereby the measured downhole tool pressure is isolatable from the measured downhole forces on the drill collar(s).

First claim

What is claimed is:

1. A downhole measurement assembly of a downhole tool positionable in a wellbore penetrating a subterranean formation, the downhole tool comprising a bottomhole assembly with a drill bit at an end thereof deployable into the wellbore on a drill string, comprising:
at least one drill collar having at least one compensation portion and at least one force portion with a load path therethrough, the at least one compensation portion having a different dimension from the at least one force portion;
a plurality of compensation sensors positionable about the at least one compensation portion to measure downhole tool pressures applied thereto, wherein the plurality of compensation sensors are positioned a distance from the load path such that the plurality of compensation sensors are isolated from a load applied to the at least one force portion; and
a plurality of force sensors positionable about the at least one force portion to measure downhole forces applied thereto;
wherein the plurality of compensation sensors and the plurality of force sensors are positionable about the at least one drill collar in a strain configuration along the load path whereby the measured downhole tool pressure is isolatable from the measured downhole forces on the at least one drill collar.

2. The downhole measurement assembly of claim 1 , wherein the strain configuration comprises a Wheatstone bridge.

3. The downhole measurement assembly of claim 1 , wherein the plurality of force sensors are at a force depth about the at least one force portion and the plurality of compensation sensors are at a compensation depth about the at least one compensation portion.

4. The downhole measurement assembly of claim 1 , wherein the plurality of force sensors and the plurality of compensation sensors are strain gauges.

5. The downhole measurement assembly of claim 1 , wherein the at least one drill collar comprises a plurality of drill collars, the plurality of compensation sensors positionable about a first of the plurality of drill collars and the plurality of force sensors positionable about a second of the plurality of drill collars.

6. The downhole measurement assembly of claim 5 , wherein the compensation sensors are positionable between the first and the second of the plurality of drill collars.

7. The downhole measurement assembly of claim 5 , wherein the force sensors are positionable between the first and the second of the plurality of drill collars.

8. The downhole measurement assembly of claim 5 , wherein the force sensors are positionable about an outer surface of the second of the plurality of drill collars.

9. The downhole measurement assembly of claim 5 , further comprising gaskets between the plurality of drill collars.

10. The downhole measurement assembly of claim 1 , wherein the plurality of compensation sensors are positionable on opposite sides of the at least one drill collar and wherein the plurality of force sensors are positionable on opposite sides of the at least one drill collar.

11. The downhole measurement assembly of claim 1 , wherein the plurality of compensation sensors and the plurality of force sensor are aligned about the at least one drill collar.

12. The downhole measurement assembly of claim 1 , wherein the compensations sensors and the force sensors are offset about the at least one drill collar.

13. The downhole measurement assembly of claim 1 , wherein the at least one drill collar has a plurality of cavities for receiving the plurality of compensation sensors and the plurality of force sensors.

14. The downhole measurement assembly of claim 1 , wherein the at least one drill collar comprises a first drill collar and a second drill collar, the first drill collar having a female end matingly connectable to a male end of the second drill collar.

15. The downhole measurement assembly of claim 14 , wherein the second drill collar has a male shoulder engageable with a female shoulder of the second drill collar.

16. The downhole measurement assembly of claim 15 , wherein the second drill collar has a first cavity and a second cavity on an outer surface thereof with the male shoulder therebetween, the compensation sensors positionable in the first cavity and the force sensors positionable in the second cavity.

17. The downhole measurement assembly of claim 14 , further comprising a seal between the first and second drill collars.

18. The downhole measurement assembly of claim 1 , wherein the at least one drill collar comprises a piston drill collar receivable into a cylinder drill collar and movable therein in response to forces applied thereto.

19. The downhole measurement assembly of claim 14 , further comprising a threaded connection between the first and second drill collars.

20. The downhole measurement assembly of claim 19 , wherein the threaded connection is between the male shoulder and a tip of the first drill collar.

21. A downhole tool positionable in a wellbore penetrating a subterranean formation, the downhole tool deployable into the wellbore on a drill string, comprising:
a drill bit;
a bottom hole assembly comprising a downhole measurement assembly, the downhole measurement assembly comprising:
at least one drill collar having at least one compensation portion and at least one force portion with a load path therethrough, the at least one compensation portion having a different dimension from the at least one force portion;
a plurality of compensation sensors positionable about the at least one compensation portion to measure downhole tool pressures applied thereto; and
a plurality of force sensors positionable about the at least one force portion to measure downhole forces applied thereto, wherein the plurality of compensation sensors are positioned a distance from the load path such that the plurality of compensation sensors are isolated from a load applied to the at least one force portion;
wherein the plurality of compensation sensors and the plurality of force sensors are positionable about the at least one drill collar in a strain configuration along the load path whereby the measured downhole tool pressure is isolatable from the measured downhole forces on the at least one drill collar.

22. The downhole tool of claim 21 , further comprising a surface unit operatively connectable to the downhole measurement assembly.

23. The downhole tool of claim 21 , wherein the bottom hole assembly further comprises a downhole unit operatively connectable to the downhole measurement assembly.

24. The downhole tool of claim 21 , wherein the bottom hole assembly further comprises a logging while drilling tool.

25. The downhole tool of claim 21 , wherein the at least one drill collar comprises a plurality of drill collars, the compensation portion about a first of the plurality of drill collars and the force portion about a second of the plurality of drill collars.

26. A method of measuring downhole parameters of a downhole tool positionable in a wellbore penetrating a subterranean formation, comprising:
deploying the downhole tool into the wellbore on a drill string, the downhole tool comprising a downhole measurement assembly, comprising:
at least one drill collar having at least one compensation portion and at least one force portion with a load path therethrough, the at least one compensation portion having a different dimension from the at least one force portion; and
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Assignees

• Nat Oilwell Dht Lp

Inventors

• Clark Kevin
• Tutt Joshua

Classifications

• E21B47/16

  through the drill string or casing {, e.g. by torsional acoustic waves} · CPC title

• E21B47/06 Primary

  Measuring temperature or pressure · CPC title

• E21B17/16

  Drill collars · CPC title

• E21B47/007 Primary

  Measuring stresses in a pipe string or casing (for locating blocked portions of pipes E21B47/09) · CPC title

• E21B12/00

  Accessories for drilling tools · CPC title