Coupler compliance tuning for mitigating shock produced by well perforating

• US 8,393,393 B2
• Filed: 12/14/2011
• Issued: 03/12/2013
• Est. Priority Date: 12/17/2010
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Rodgers, John P., Glenn, Timothy S., Burleson, John D., Serra, Marco
• Primary Examiner(s): GAY, JENNIFER HAWKINS
• Application Number:
  US13/325,726
• Publication Number:
  US 20120152614A1
• Time in Patent Office: 454 Days
• Field of Search: 166/55.1, 166/297, 175 1- 455, 175/4.6, 89/11.5, 102/320
• US Class Current: 166/297
• CPC Class Codes: E21B 43/1195 Replacement of drilling mud; decrease of undesirable shock waves

Abstract

A method of mitigating perforating effects produced by well perforating can include causing a shock model to predict perforating effects for a proposed perforating string, optimizing a compliance curve of at least one proposed coupler, thereby mitigating the perforating effects for the proposed perforating string, and providing at least one actual coupler having substantially the same compliance curve as the proposed coupler. A well system can comprise a perforating string including at least one perforating gun and multiple couplers, each of the couplers having a compliance curve, and at least two of the compliance curves being different from each other. A method of mitigating perforating effects produced by well perforating can include interconnecting multiple couplers spaced apart in a perforating string, each of the couplers having a compliance curve, and selecting the compliance curves based on predictions by a shock model of shock generated by the perforating string.

Claims

1. A method of mitigating perforating effects produced by well perforating, the method comprising:

interconnecting multiple couplers spaced apart in a perforating string, each of the couplers mitigating transmission of shock through the perforating string and having a compliance curve; and

selecting the compliance curves based on predictions by a shock model of perforating effects generated by firing the perforating string.

2. The method of claim 1, further comprising inputting a three-dimensional model of the perforating string to the shock model.

3. The method of claim 1, further comprising determining the compliance curves which result in minimized transmission of the shock through the perforating string.

4. The method of claim 1, further comprising determining the compliance curves which result in minimized stresses in perforating guns of the perforating string.

5. The method of claim 1, wherein the compliance curve for one of the couplers is different from the compliance curve for another of the couplers.

6. The method of claim 1, wherein the compliance curves vary along the perforating string.

7. The method of claim 1, wherein at least two of the couplers have different compliance curves.

8. The method of claim 1, wherein at least one of the couplers is connected in the perforating string between perforating guns.

9. A well system, comprising:

a perforating string including at least one perforating gun and multiple couplers, each of the couplers having a compliance curve, and at least two of the compliance curves being different from each other, wherein the different compliance curves are based on relative positions of at least two of the couplers in the perforating string, the couplers being in the perforating string concurrently.

10. The well system of claim 9, wherein at least one of the couplers is interconnected between first and second perforating guns.

11. The well system of claim 9, wherein at least one of the couplers is interconnected between the perforating gun and a firing head.

12. The well system of claim 9, wherein at least one of the couplers is interconnected between the perforating gun and a packer.

13. The well system of claim 9, wherein at least one of the couplers is interconnected between a firing head and a packer.

14. The well system of claim 9, wherein a packer is interconnected between at least one of the couplers and the perforating gun.

15. The well system of claim 9, wherein the couplers mitigate transmission of shock through the perforating string.

16. A method of mitigating perforating effects produced by well perforating, the method comprising:

causing a shock model to predict the perforating effects for a proposed perforating string; and

optimizing a compliance curve of at least one coupler which mitigates transmission of shock, thereby mitigating the perforating effects for an actual perforating string which includes the at least one coupler.

17. The method of claim 16, wherein causing the shock model to predict the perforating effects further comprises inputting a three-dimensional model of the proposed perforating string to the shock model.

18. The method of claim 16, wherein optimizing the compliance curve further comprises determining the compliance curve which results in minimized transmission of the shock through the proposed perforating string.

19. The method of claim 16, wherein optimizing the compliance curve further comprises determining the compliance curve which results in minimized stress in at least one perforating gun of the proposed perforating string.

20. The method of claim 16, wherein the optimizing step further comprises optimizing the compliance curve for each of multiple couplers.

21. The method of claim 20, wherein a first compliance curve for a first coupler is different from a second compliance curve for a second coupler.

22. The method of claim 21, wherein the first compliance curve for the first coupler varies from the second compliance curve for the second coupler based on relative positions of the first and second couplers in the proposed perforating string.

23. The method of claim 20, further comprising interconnecting the multiple couplers in the actual perforating string.

24. The method of claim 23, wherein a first compliance curve for a first coupler is different from a second compliance curve for a second coupler based on relative positions of the first and second couplers in the actual perforating string.

25. The method of claim 16, further comprising interconnecting multiple couplers in the actual perforating string, each of the couplers having a respective optimized compliance curve.

26. The method of claim 25, wherein at least one of the couplers is connected in the actual perforating string between first and second perforating guns.

27. The method of claim 16, further comprising comparing the perforating effects predicted by the shock model both with and without the coupler in the proposed perforating string.