Internal coaxial cable seal system

• US 20050070144A1
• Filed: 11/05/2004
• Published: 03/31/2005
• Est. Priority Date: 01/31/2003
• Status: Active Grant

• Current Assignee: IntelliServ, LLC (NOV, Inc.)
• Original Assignee: Intelliserv, Inc. (NOV, Inc.)
• Inventors: Hall, David R., Dahlgren, Scott Steven, Briscoe, Michael A., Sneddon, Cameron
• Granted Patent: US 7,080,998 B2
• Time in Patent Office: Days
• US Class Current: 439/191
• CPC Class Codes: E21B 17/003 with electrically conducting or insulating means E21B17/028 and E21B17/023 take precedence
• CPC Class Codes: E21B 17/0285 characterised by electrically insulating elements
• CPC Class Codes: E21B 47/13 by electromagnetic energy, e.g. radio frequency
• CPC Class Codes: F16L 15/003 with sealing rings
• CPC Class Codes: H01F 2038/143 for signals
• CPC Class Codes: H01R 13/523 for use under water
• CPC Class Codes: H01R 13/6633 with inductive component, e.g. transformer
• CPC Class Codes: H01R 2103/00 Two poles
• CPC Class Codes: H01R 24/566 Hollow cables
• CPC Class Codes: H01R 9/05 for coaxial cables
• CPC Class Codes: H01R 9/0521 Connection to outer conductor by action of a nut

Abstract

The invention is a seal system for a coaxial cable and is placed within the coaxial cable and its constituent components. A series of seal stacks including load ring components and elastomeric rings are placed on load bearing members within the coaxial cable sealing the annular space between the coaxial cable and an electrical contact passing there through. The coaxial cable is disposed within drilling components to transmit electrical signals between drilling components within a drill string. The seal system can be used in a variety of downhole components, such as sections of pipe in a drill string, drill collars, heavy weight drill pipe, and jars.

Claims

1. A coaxial cable seal system comprising:

a coaxial cable comprising a conductive tube and a conductive core within it, the conductive tube having within it a base component anchored proximate an end of a downhole component;

a communications element mounted in the downhole component intermediate the base component and the end of the downhole component, the communications element having an electrically isolated contact adapted to be in removeably electrical communication with the conductive core;

the coaxial cable seal system comprising at least one seal stack comprising an annular elastomeric component and at least one load ring component;

wherein the coaxial cable seal system is disposed between the tube and the electrically isolated contact to provide a seal therebetween.

2. The coaxial cable seal system of claim 1 wherein the downhole component is selected from the group consisting of tool joints, drill pipe, drill collars, jars, drilling motors, measuring while drilling tools, and stabilizers.

3. The seal system of claim 1 further comprising:

a tubular spacer extending from the transmission element and, upon assembly, lying adjacent a terminating annular rigid component of the seal stack,

the electrically isolated contact passing, in order, through the tubular spacer, the terminating annular rigid component, at least one seal stack, a plurality of angled annular components, a washer, and the base component.

4. The seal system of claim 3 comprising more than one seal stack lying serially on top of each other within the conductive tube of the coaxial cable.

5. The seal system of claim 4 wherein the contact is wire insulated with an insulating polymer.

6. The seal system of claim 5 wherein the wire has an insulated portion and a non-insulated portion.

7. The seal system of claim 6 wherein the insulated portion passes through the tubular spacer, the terminating annular rigid component and the seal stack and the non-insulated portion through the angled annular components, the washer, and the base component.

8. The seal system of claim 6 wherein an inner diameter of the angled annular components is smaller then a diameter of the insulated portion of the wire.

9. The seal system of claim 3 comprising first and second angled annular components in the seal stack wherein supplementary angles of the first and second angled annular components are approximately fifty degrees.

10. The seal system of claim 3 wherein the load ring component of at least one of the seal stacks comprises a double sided trough.

11. The seal system of claim 1 wherein the elastomeric component comprises an o-ring.

12. The seal system of claim 1 wherein the elastomeric component comprises an x-ring.

13. The seal system of claim 1 wherein the elastomeric component comprises elastomeric material having a minimum hardness of 70 on a Shore A hardness scale.

14. The seal system of claim 13 wherein the elastomeric component is made of a material chosen from the group consisting of perfluoroelastomers, fluoroelastomers, acrylonitrile butadiene, highly saturated nitrile elastomer compounds, or carboxylated nitrile compounds.

15. The seal system of claim 13 wherein the elastomeric material is made according to the ASTM-D standard 1418, and selected from the group consisting of FKM, FFKM, XNBR, HNBR, and NBR.

16. The seal system of claim 1 wherein the elastomeric component is a chemical resistant material.

17. The seal system of claim 3 wherein a trough of the load ring component is a shallow groove wherein the groove depth is less than half the height of the rigid component.

18. The seal system of claim 3 wherein a trough of the load ring component forms a v-shape.

19. The seal system of claim 3 wherein a trough of the load ring component forms a generally v-shape with a concave bottom.

20. The seal system of claim 3 wherein a trough of the load ring component forms a half circle bottom.

21. The seal system of claim 3 wherein the load ring component is made of polyether ether ketone.

22. The seal system of claim 3 wherein the elastomeric component is placed within a trough formed on one side of the load ring component.

23. The seal system of claim 3 wherein the washer is made of ceramic.

24. The washer of claim 23 wherein the ceramic is selected from the group consisting of cemented tungsten carbide, alumina, silicon carbide, silicone nitride, and polycrystalline diamond.

25. The seal system of claim 3 wherein the washer is made of a plastic material.

26. The seal system of claim 25 wherein the plastic material is selected from the group consisting of polyether ether ketone, glass filled polyether ether ketone, carbon filled polyether ether ketone, polyether ketone ketone, glass filled polyether ketone ketone, mineral filled polyether ketone ketone, and carbon filled polyether ketone ketone.

27. The seal system of claim 3 wherein the washer is made of garolite.

28. The seal system of claim 1 wherein a connector provides electrical communication between the conductive core and the contact.

29. The seal system of claim 28 wherein the connector, the contact, and/or the conductive core are coated with a corrosion resistant material.

30. The seal system of claim 29 wherein the corrosion resistant coating is selected from the group consisting of gold plating, gold cladding, and conductive noble metallic alloys.

31. The seal system of claim 28 wherein the connector, the contact, and/or the conductive core are made corrosion resistant by dipping or painting with conductive paints or liquid coatings having conductive properties.

32. The seal system of claim 28 wherein the connector, the contact, and/or the conductive core are coated with a liquid repelling insulating material.

33. The seal system of claim 32 wherein material is a grease, a gel, or a plastic.

34. An internal coaxial cable seal system for a downhole component, the downhole component comprising:

a coaxial cable comprising a conductive tube and a conductive core, the conductive tube having an end proximate an end of the downhole component and anchored to the downhole component by a base component;

a transmission element mounted in the downhole component intermediate the end of the conductive tube and the end of the component, the transmission element having a contact adapted to be removeably electrically connected with the conductive core;

the internal coaxial cable seal system disposed within the conductive tube intermediate the base component and the end of the tube and comprising a washer lying adjacent the base component and at least one seal stack lying adjacent the washer;

the seal stack comprising an annular elastomeric component compressed within the conductive tube and energized by a load ring component;

wherein the seal stack is adapted to receive and seal the contact within the conductive tube.

35. The seal system of claim 34 comprising more than one seal stack lying serially on top of each other within the conductive tube of the coaxial cable.

36. The seal system of claim 35 wherein the contact is wire insulated with an insulating polymer.

37. The seal system of claim 36 wherein the wire has an insulated portion and a non-insulated portion.

38. The seal system of claim 37 wherein the insulated portion passes through, in order, a tubular spacer, a terminating annular rigid component, and the seal stack;

and the non-insulated portion passes through, in order, a plurality of angled annular components, the washer, and the base component.

39. The seal system of claim 38 wherein an inner diameter of the angled annular components is smaller than a diameter of the insulated portion of the wire.

40. The seal system of claim 38 comprising first and second angled annular components in the seal stack wherein supplementary angles of the first and second angled annular components are approximately fifty degrees.

41. The seal system of claim 34 wherein the load ring component of at least one of the seal stacks comprises a double sided trough.

42. The seal system of claim 34 wherein the elastomeric component comprises an o-ring.

43. The seal system of claim 34 wherein the elastomeric component comprises an x-ring.

44. The seal system of claim 34 wherein the elastomeric component comprises elastomeric material having a minimum hardness of 70 on a Shore A hardness scale.

45. The seal system of claim 44 wherein the elastomeric component is made of a material chosen from the group consisting of perfluoroelastomers, fluoroelastomers, acrylonitrile butadiene, highly saturated nitrile elastomer compounds, or carboxylated nitrile compounds.

46. The seal system of claim 44 wherein the elastomeric material is made according to the ASTM-D standard 1418, and selected from the group consisting of FKM, FFKM, XNBR, HNBR, and NBR.

47. The seal system of claim 34 wherein the elastomeric component is a chemical resistant material.

48. The seal system of claim 34 wherein a trough of the load ring component is a shallow groove wherein the groove depth is less than half the height of the rigid component.

49. The seal system of claim 34 wherein a trough of the load ring component forms a v-shape.

50. The seal system of claim 34 wherein a trough of the load ring component forms a generally v-shape with a concave bottom.

51. The seal system of claim 34 wherein a trough of the load ring component forms a half circle bottom.

52. The seal system of claim 34 wherein the load ring component is made of polyether ether ketone.

53. The seal system of claim 34 wherein the elastomeric component is placed within a trough formed on one side of the rigid component.

54. The seal system of claim 34 wherein the washer is made of ceramic.

55. The seal system of claim 54 wherein the ceramic is selected from the group consisting of cemented tungsten carbide, alumina, silicon carbide, silicone nitride, and polycrystalline diamond.

56. The seal system of claim 34 wherein the washer is made of a plastic material.

57. The seal system of claim 56 wherein the plastic material is selected from the group consisting of polyether ether ketone, glass filled polyether ether ketone, carbon filled polyether ether ketone, polyether ketone ketone, glass filled polyether ketone ketone, mineral filled polyether ketone ketone, and carbon filled polyether ketone ketone.

58. The seal system of claim 34 wherein the washer is made of garolite.

59. The seal system of claim 34 wherein a connector provides electrical communication between the conductive core and the contact.

60. The seal system of claim 59 wherein the connector, the contact, and/or the conductive core 73 are coated with a corrosion resistant material.

61. The seal system of claim 60 wherein the corrosion resistant coating is selected from the group consisting of gold plating, gold cladding, and conductive noble metallic alloys.

62. The seal system of claim 59 wherein the connector, the contact, and/or the conductive core are made corrosion resistant by dipping or painting with conductive paints or liquid coatings having conductive properties.

63. The seal system of claim 59 wherein the connector, the contact, and/or the conductive core are coated with a liquid repelling insulating material.

64. The seal system of claim 63 wherein material is a grease, a gel, or a plastic.