FLOATING PLUG PRESSURE EQUALIZATION IN OILFIELD DRILL BITS

• US 20130153304A1
• Filed: 12/05/2012
• Published: 06/20/2013
• Est. Priority Date: 12/14/2011
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: CRAWFORD, Micheal B.
• Granted Patent: US 8,800,689 B2
• Time in Patent Office: Days
• US Class Current: 175/228
• CPC Class Codes: E21B 10/00 Drill bits specially adapted for deflecting the direction of boring E21B7/064; with means for collecting substances E21B27/00
• CPC Class Codes: E21B 10/24 characterised by lubricating details E21B10/23 takes precedence
• CPC Class Codes: E21B 10/25 characterised by sealing details
• CPC Class Codes: E21B 10/60 characterised by conduits or nozzles for drilling fluids for roller bits E21B10/18; for percussion drill bits E21B10/38

Abstract

A drill bit of the type used to drill a wellbore in the earth can comprise a bore formed in the drill bit, and a plug sealingly and reciprocably disposed in the bore, whereby the plug prevents fluid communication between sections of the bore in the drill bit. The plug can comprise a spherically-shaped member. The plug can comprise a floating plug sealingly and reciprocably disposed in the bore, whereby pressure in the different sections of the bore on respective opposite sides of the plug is substantially equalized.

Claims

1-6. -6. (canceled)

7. A wellbore drill bit, comprising:

a bore formed in the drill bit; and

a plug sealingly and reciprocably disposed in the bore, whereby the plug prevents fluid communication between first and second sections of the bore in the drill bit, wherein the first bore section is in fluid communication with an exterior of the drill bit, and wherein the second bore section is in fluid communication with an annular gap between two seals.

8. The drill bit of claim 7, wherein the seals provide sealing engagement between a journal and a cutting structure which rotates about the journal.

9. A wellbore drill bit, comprising:

a bore formed in the drill bit;

a plug sealingly and reciprocably disposed in the bore, whereby the plug prevents fluid communication between first and second sections of the bore in the drill bit; and

a bypass chamber which is enlarged relative to the bore, and which is in communication with the bore, whereby the plug is displaceable into the bypass chamber.

10. The drill bit of claim 9, wherein fluid can bypass the plug when the plug is in the bypass chamber.

11. The drill bit of claim 9, wherein the plug is displaceable into the bypass chamber in response to loss of lubricant from the drill bit.

12. A wellbore drill bit, comprising:

a bore formed in the drill bit;

a plug sealingly and reciprocably disposed in the bore, whereby the plug prevents fluid communication between first and second sections of the bore in the drill bit; and

at least two seals which seal off an annular gap, and wherein the first bore section is in fluid communication with the annular gap between the seals.

13. The drill bit of claim 12, wherein the second bore section is in fluid communication with the annular gap.

14. The drill bit of claim 12, wherein the second bore section is in fluid communication with a lubricant chamber in the drill bit.

15. The drill bit of claim 12, wherein one side of one of the seals is exposed to the annular gap between the seals, and wherein the second bore section is in fluid communication with the annular gap on an opposite side of the one of the seals.

16. The drill bit of claim 12, wherein the annular gap is formed between a journal and a cutting structure which rotates relative to the journal.

17-18. -18. (canceled)

19. A wellbore drill bit, comprising:

a bore formed in the drill bit; and

a plug sealingly and reciprocably disposed in the bore, whereby the plug prevents fluid communication between first and second sections of the bore in the drill bit, wherein fluid communication between the first and second sections of the bore is permitted when a pressure differential across the plug exceeds a predetermined level.

20-26. -26. (canceled)

27. A wellbore drill bit, comprising:

a bore formed in the drill bit; and

a spherically-shaped plug sealingly and slidingly disposed in the bore, whereby the plug prevents fluid communication between first and second sections of the bore in the drill bit, wherein the first bore section is in fluid communication with an exterior of the drill bit, and wherein the second bore section is in fluid communication with an annular gap between two seals.

28. The drill bit of claim 27, wherein the seals provide sealing engagement between a journal and a cutting structure which rotates about the journal.

29. A wellbore drill bit, comprising:

a bore formed in the drill bit;

a spherically-shaped plug sealingly and slidingly disposed in the bore, whereby the plug prevents fluid communication between first and second sections of the bore in the drill bit; and

a bypass chamber which is enlarged relative to the bore, and which is in communication with the bore, whereby the plug is displaceable into the bypass chamber.

30. The drill bit of claim 29, wherein fluid can bypass the plug when the plug is in the bypass chamber.

31. The drill bit of claim 29, wherein the plug is displaceable into the bypass chamber in response to loss of lubricant from the drill bit.

32. A wellbore drill bit, comprising:

a bore formed in the drill bit;

a spherically-shaped plug sealingly and slidingly disposed in the bore, whereby the plug prevents fluid communication between first and second sections of the bore in the drill bit; and

at least two seals which seal off an annular gap, and wherein the first bore section is in fluid communication with the annular gap between the seals.

33. The drill bit of claim 32, wherein the second bore section is in fluid communication with the annular gap.

34. The drill bit of claim 32, wherein the second bore section is in fluid communication with a lubricant chamber in the drill bit.

35. The drill bit of claim 32, wherein one side of one of the seals is exposed to the annular gap between the seals, and wherein the second bore section is in fluid communication with the annular gap on an opposite side of the one of the seals.

36. The drill bit of claim 32, wherein the annular gap is formed between a journal and a cutting structure which rotates relative to the journal.

37-48. -48. (canceled)

49. A wellbore drill bit, comprising:

a bore formed in a body of the drill bit; and

a floating plug sealingly and reciprocably disposed in the bore, whereby pressure in first and second sections of the bore on respective first and second opposite sides of the plug is substantially equalized, wherein the first bore section is in fluid communication with an exterior of the drill bit, and wherein the second bore section is in fluid communication with an annular gap between two seals.

50. The drill bit of claim 49, wherein the seals provide sealing engagement between a journal and a cutting structure which rotates about the journal.

51. A wellbore drill bit, comprising:

a bore formed in a body of the drill bit;

a floating plug sealingly and reciprocably disposed in the bore, whereby pressure in first and second sections of the bore on respective first and second opposite sides of the plug is substantially equalized; and

a bypass chamber which is enlarged relative to the bore, and which is in communication with the bore, whereby the plug is displaceable into the bypass chamber.

52. The drill bit of claim 51, wherein fluid can bypass the plug when the plug is in the bypass chamber.

53. The drill bit of claim 51, wherein the plug is displaceable into the bypass chamber in response to loss of lubricant from the drill bit.

54. A wellbore drill bit, comprising:

a bore formed in a body of the drill bit;

a floating plug sealingly and reciprocably disposed in the bore, whereby pressure in first and second sections of the bore on respective first and second opposite sides of the plug is substantially equalized; and

at least two seals which seal off an annular gap, and wherein the first bore section is in fluid communication with the annular gap between the seals.

55. The drill bit of claim 54, wherein the second bore section is in fluid communication with the annular gap.

56. The drill bit of claim 54, wherein the second bore section is in fluid communication with a lubricant chamber in the body of the drill bit.

57. The drill bit of claim 54, wherein one side of one of the seals is exposed to the annular gap between the seals, and wherein the second bore section is in fluid communication with the annular gap on an opposite side of the one of the seals.

58. The drill bit of claim 54, wherein the annular gap is formed between a journal and a cutting structure which rotates relative to the journal.

59-62. -62. (canceled)