Emergency release tool

• US 5,984,006 A
• Filed: 10/03/1997
• Issued: 11/16/1999
• Est. Priority Date: 10/04/1996
• Status: Expired due to Term

• Current Assignee: Camco International Inc. (SLB)
• Original Assignee: Camco International Inc. (SLB)
• Inventors: Read, Dennis M., Leismer, Dwayne D.
• Primary Examiner(s): SUCHFIELD, GEORGE A
• Application Number:
  US08/943,887
• Time in Patent Office: 774 Days
• Field of Search: 166/63, 166/65.1, 166/66.6, 166/242.2, 166/242.6, 166/242.7, 166/377, 285/39, 285/360, 285/376, 285/401
• US Class Current: 166/63
• CPC Class Codes: E21B 17/028 Electrical or electro-magnetic connections
• CPC Class Codes: E21B 17/06 Releasing-joints, e.g. safety joints
• CPC Class Codes: E21B 23/042 using a single piston or multiple mechanically interconnected pistons

Abstract

An improved emergency release tool is provided to releasably connect a coiled tubing to one or more downhole tools. The emergency release tool broadly includes a releasable slip for holding a coiled tubing, the releasable slip being secured to a first end of a slip case, the slip case being disposed within a slip housing and a lower housing, the slip housing being movable from a locked position to a released position; a piston slidably disposed about the slip case and being moveable from a locked position to a released position; a first end of the lower housing being releasably connected to a second end of the slip housing when the slip housing is in its locked position; and, a remotely activated means for moving the piston and the slip housing from their locked positions to their released positions to disengage the releasable slip from the coiled tubing and enable the coiled tubing to be removed from the tool. A quick disconnect coupler is also provided, and broadly includes a pin connector having a series of lugs; a box connector for receiving the pin connector and having a series of recesses to engage and hold the lugs inside the box connector; and, a load ring between the box connector and the pin connector for transmitting compressive loads through the connection.

Claims

1. An emergency release tool comprising:

a releasable slip for holding a coiled tubing, the releasable slip being secured to a first end of a slip case, the slip case being disposed within a slip housing and a lower housing, the slip housing being movable from a locked position to a released position;

a piston slidably disposed about the slip case and being moveable from a locked position to a released position;

a first end of the lower housing being releasably connected to a second end of the slip housing when the slip housing is in its locked position; and

,

a remotely activated mechanism for moving the piston and the slip housing from their locked positions to their released positions to disengage the releasable slip from the coiled tubing and enable the coiled tubing to be removed from the tool.

2. The emergency release tool of claim 1, further including a loading nut movably secured to a first end of the slip housing and mating with the releasable slip for holding the coiled tubing.

3. The emergency release tool of claim 2, wherein the loading nut is threadably secured to the first end of the slip housing.

4. The emergency release tool of claim 2, wherein the loading nut includes a flared portion for mating with a flared portion on the releasable slip.

5. The emergency release tool of claim 4, wherein the flared portions on the loading nut and on the slip are flared at angles of approximately three degrees.

6. The emergency release tool of claim 2, wherein the loading nut includes a fishing profile for engaging a well tool to be used in retrieving the emergency release tool and a bottom hole assembly attached thereto upon the coiled tubing being released from the emergency release tool.

7. The emergency release tool of claim 1, wherein the second end of the slip housing further includes at least one dog and is telescopically received within the first end of the lower housing, the piston holding the at least one dog in an annular recess in the first end of the lower housing when the piston is in its locked position to connect the slip housing to the lower housing, and the piston releasing the at least one dog to disconnect the slip housing and the lower housing and moving the slip housing to its released position when the piston is moved from its locked position to its released position.

8. The emergency release tool of claim 7, wherein the annular recess in the lower housing may function as a redundant fishing profile for engaging a well tool to be used in retrieving the emergency release tool and a bottom hole assembly attached thereto upon the coiled tubing being released from the emergency release tool and upon detachment from the tool of the releasable slip, the slip case, the slip housing, and the piston.

9. The emergency release tool of claim 1, wherein the lower housing further includes an annular load bearing shoulder that may function as a redundant fishing profile for engaging a well tool to be used in retrieving the emergency release tool and a bottom hole assembly attached thereto upon the coiled tubing being released from the emergency release tool and upon detachment from the tool of the releasable slip, the slip case, the slip housing, and the piston.

10. The emergency release tool of claim 1, wherein the slip case includes an outer surface having a shoulder and at least one recess for housing at least one locking dog, the at least one locking dog being in a compressed position when the slip housing is in its locked position, and the at least one locking dog being moveable to engage an annular recess within the slip housing when the slip housing is in its released position.

11. The emergency release tool of claim 1, wherein the piston is releasably secured to the lower housing when the piston is in its locked position.

12. The emergency release tool of claim 11, further including a collet being releasably connected to the piston and to the lower housing, the collet being released from the piston when the piston is shifted from its locked position to its released position.

13. The emergency release tool of claim 12, wherein the collet includes a plurality of fingers having threaded portions at distal ends thereof for mating with a threaded portion on the lower housing to releasably secure the collet to the lower housing.

14. The emergency release tool of claim 12, wherein the collet is releasably secured to the piston by a shear pin.

15. The emergency release tool of claim 13, wherein the slip case further includes a locking shoulder for loading the distal ends of the collet fingers when a well tool is being used to engage a fishing profile on the tool to retrieve the tool and an attached bottom hole assembly.

16. The emergency release tool of claim 1, wherein the remotely activated means includes a propellant that, when ignited, forces the piston and the slip housing from their locked positions to their released positions.

17. The emergency release tool of claim 16, wherein the propellant is disposed about the slip case and beneath the piston, and is remotely ignited by an electrical signal.

18. The emergency release tool of claim 1, wherein the remotely activated means includes a gas that, when released, forces the piston and the slip housing from their locked positions to their released positions.

19. The emergency release tool of claim 1, wherein the remotely activated means is connected to and activated by a conductor cable running through the coiled tubing from the earth'"'"'s surface to the tool.

20. The emergency release tool of claim 19, wherein the conductor cable may be remotely detached from the emergency release tool and removed from the coiled tubing so that conventional well tools may be used to remove the emergency release tool and a bottom hole assembly attached thereto from the well.

21. The emergency release tool of claim 19, further including means for sealing individual conductors within the conductor cable from drilling fluid being circulated through the tool.

22. The emergency release tool of claim 21, wherein the conductor sealing means includes:

an anchor, an armor nut, a conductor cable sealing connector, and a flow tube;

the anchor being received within the coiled tubing and removably connected to the armor nut;

the anchor and the armor nut having cooperating inclined surfaces for holding an armor portion of the conductor cable;

the conductor cable sealing connector having a plurality of longitudinal bores extending therethrough and including a carrier plug, a composite seal, and a follower plug, the composite seal being disposed between the carrier plug and the follower plug, and each of the individual conductors passing through one of the plurality of longitudinal bores; and

,

a first end of the flow tube being connected to the armor nut to compress the sealing connector between a shoulder on the flow tube and a shoulder on the armor nut and to compress the composite seal and seal the individual conductors from the drilling fluid, and a second end of the flow tube being received within a longitudinal bore of the inner mandrel.

23. The emergency release tool of claim 22, wherein the conductor cable may be remotely detached from the tool by shearing the armor from between the anchor and the armor nut and removed from the coiled tubing so that conventional well tools may be used to remove the emergency release tool and a bottom hole assembly attached thereto from the well.

24. The emergency release tool of claim 1, wherein the piston includes a shoulder disposed beneath an aperture in the slip housing, whereby well bore pressure is applied through the aperture to the piston shoulder to maintain a downward force on the piston to counteract any upward forces on the piston that may develop during the drilling process, other than forces generated as a result of the activation of the remotely activated means.

25. The emergency release tool of claim 1, wherein the tool releases the coiled tubing in a nondestructive manner so as to leave no enlarged diameters on the tubing that could interfere with removal of the coiled tubing from a well.

26. The emergency release tool of claim 1, wherein, upon activation of the remotely activated means to disengage the coiled tubing from the tool, no part of a conductor sealing means within the tool is larger than an outer diameter of the coiled tubing, so that removal of the conductor sealing means from the tool will not interfere with removal of the coiled tubing from a well.

27. The emergency release tool of claim 1, wherein the coiled tubing is released from the tool solely by remote activation of the remotely activated means without mechanical manipulation of the emergency release tool by a well tool.

28. The emergency release tool of claim 1, wherein the coiled tubing is released from the tool solely by remote activation of the remotely activated means without movement of the coiled tubing.

29. The emergency release tool of claim 1, wherein the coiled tubing is released from the tool solely by remote activation of the remotely activated means without movement of a bottom hole assembly connected to the emergency release tool.

30. The emergency release tool of claim 1, wherein the coiled tubing need only be deburred to be installed adjacent the releasable slip.

31. The emergency release tool of claim 1, wherein a quick disconnect coupler is attached to a second end of the lower housing, the quick disconnect coupler including a pin connector having a series of lugs, a box connector for receiving the pin connector and having a series of recesses to engage and hold the lugs, a rigid spacer between the box and pin connectors for transmitting operating loads through the connection, and an integral sealing means for maintaining a fluidic pressure seal between the pin and box connectors.

32. An emergency release tool comprising:

a loading nut having a longitudinal bore extending therethrough, a first end, and a second end having an outer surface, the longitudinal bore having a flared portion at the second end of the loading nut, and the outer surface of the second end having a threaded portion;

a slip housing having a longitudinal bore extending therethrough, a first end, and second end, the longitudinal bore having a threaded portion at the first end of the slip housing for mating with the threaded portion on the loading nut and an annular recess forming a shoulder, and the second end of the slip housing having at least one dog;

a lower housing having a longitudinal bore extending therethrough, a first end, and second end, the second end of the slip housing being telescopically received within the longitudinal bore of the lower housing at the first end thereof, and an annular recess at the first end of the lower housing for receiving the at least one dog in the second end of the slip housing;

a slip case having a longitudinal bore extending therethrough, a first end, a second end, and an outer surface, the outer surface having a shoulder and at least one recess, the at least one recess housing at least one locking dog;

at least one slip connected to the first end of the slip case and having a flared end for mating with the flared end of the loading nut and an inner surface, the inner surface having gripping teeth for gripping a coiled tubing;

a piston disposed for longitudinal movement around the slip case and being releasably secured to the lower housing when the tool is in a locked position, the at least one dog in the second end of the slip housing being held within the annular recess in the lower housing by the piston when the tool is in the locked position, the piston being movable to release the at least one dog from the annular recess when the tool is being shifted from its locked position to a released position; and

a remotely activated mechanism for moving the tool from its locked position to its released position to disengage the at least one slip from the coiled tubing.

33. The emergency release tool of claim 32, further including a collet being releasably connected to the piston and to the lower housing, the collet being released from the piston when the tool is shifted from its locked position to its released position.

34. The emergency release tool of claim 33, wherein the collet is releasably secured to the piston by at least one shear pin.

35. The emergency release tool of claim 33, wherein the collet further includes a body portion having a plurality of fingers depending therefrom, the fingers having distal ends, the distal ends having a threaded portion engaged with a threaded portion in the longitudinal bore of the lower housing.

36. The emergency release tool of claim 35, wherein the collet is disposed around a second extension of the piston and within the longitudinal bore of the lower housing, and the collet body is releasably secured to the second extension of the piston.

37. The emergency release tool of claim 32, wherein the remotely activated means includes a gas that, when released, moves the tool from its locked position to its released position.

38. The emergency release tool of claim 32, wherein the remotely activated means includes a propellant that, when ignited, moves the tool from its locked position to its released position.

39. The emergency release tool of claim 38, wherein the propellant is disposed about the slip case and beneath the piston, and is remotely ignited by an electrical signal.

40. The emergency release tool of claim 38, further including:

a charge mandrel having a main body portion and a first extension, the charge mandrel being connected to the second end of the slip case and disposed within the longitudinal bore of the lower housing, the first extension having a distal end and a propellant retaining shoulder, the main body portion having a loading shoulder for bearing against an annular load bearing shoulder in the longitudinal bore of the lower housing; and

,

a propellant retainer ring having an outer surface, a first edge, and a second edge, the retainer ring being movably connected to the distal end of the first extension of the charge mandrel, the propellant being disposed between the longitudinal bore of the lower housing and an outer surface of the first extension of the charge mandrel, and being held in place between the second edge of the ring and the retaining shoulder on the charge mandrel when the tool is in its locked position.

41. The emergency release tool of claim 40, wherein the outer surface of the propellant retainer ring includes at least one recess to facilitate the passage of gases generated upon ignition of the propellant.

42. The emergency release tool of claim 40, further including:

a collet being releasably connected to the piston and to the lower housing, the collet being released from the piston when the tool is shifted from its locked position to its released position, the collet having a body portion having a plurality of fingers depending therefrom, the fingers having distal ends, the distal ends having a threaded portion engaged with a threaded portion in the longitudinal bore of the lower housing; and

,

a locking shoulder on the outer surface of the propellant retainer ring adjacent a first edge thereof, the locking shoulder loading the distal ends of the collet fingers when a well tool is being used to engage a fishing profile on the tool to retrieve the tool and an attached bottom hole assembly.

43. The emergency release tool of claim 42, wherein the longitudinal bore of the loading nut further includes a fishing profile for engaging a well tool to be used in retrieving the emergency release tool and a bottom hole assembly attached thereto upon the coiled tubing being released from the emergency release tool, the forces imparted to the fishing profile by the well tool being transferred to the bottom hole assembly through the shoulder on the slip housing that is bearing against the shoulder on the slip case, through the locking shoulder on the propellant retainer ring that is bearing against the distal ends of the collet fingers, and through the threaded portions on the collet fingers that are threadably engaged with the threaded portion on the lower housing, the threaded portions on the collet fingers and the lower housing being designed to fail at a preselected load, whereby, upon the preselected load being exceeded, the collet being disengaged from the lower housing, and the tool, except for the lower housing, being disengaged from the bottom hole assembly.

44. The emergency release tool of claim 40, wherein the main body portion of the charge mandrel includes an electrical conductor conduit for receiving an individual conductor of a conductor cable.

45. The emergency release tool of claim 44, wherein the main body portion further includes a connector disposed in the electrical conductor conduit for connecting an individual conductor of a conductor cable to a conductor connected to the propellant.

46. The emergency release tool of claim 40, further including an extension connected to a lower end of the charge mandrel for sealably receiving an upper portion of an uppermost tool in a bottom hole assembly.

47. The emergency release tool of claim 32, wherein the piston includes a first extension, a second extension, and a first shoulder adjacent the first extension, the first extension being disposed for longitudinal movement within the longitudinal bore of the slip housing and having an area of increased diameter and an area of reduced diameter, the second extension being disposed for longitudinal movement within the longitudinal bore of the lower housing, the at least one dog in the second end of the slip housing being held within the annular recess in the lower housing by the area of increased diameter on the first extension of the piston when the tool is in its locked position, and the piston being movable to release the at least one dog from the annular recess when the tool is being shifted from its locked position to its released position.

48. The emergency release tool of claim 32, wherein the flared portions on the loading nut and on the slip are flared at angles of approximately three degrees.

49. The emergency release tool of claim 32, wherein the second end of the slip housing includes at least one notch for engaging at least one prong on the first end of the lower housing.

50. The emergency release tool of claim 32, wherein the at least one slip includes a T-shaped end for mating with a corresponding T-shaped slot in the first end of the slip case.

51. The emergency release tool of claim 32, wherein the at least one locking dog housed in the slip case is spring-loaded.

52. The emergency release tool of claim 32, wherein the piston includes a shoulder disposed beneath an aperture in the slip housing, whereby well bore pressure is applied through the aperture to the piston shoulder to maintain a downward force on the piston to counteract any upward forces on the piston that may develop during the drilling process, other than forces generated as a result of the activation of the remotely activated means.

53. The emergency release tool of claim 32, wherein, when the tool is shifted from a locked position to a released position, the shoulder on the slip case engages the shoulder on the slip housing and the locking dogs move outwardly to engage the annular recess in the slip housing.

54. The emergency release tool of claim 32, wherein the remotely activated means is connected to and activated by a conductor cable running through the coiled tubing from the earth'"'"'s surface to the tool.

55. The emergency release tool of claim 54, wherein the conductor cable may be remotely detached from the emergency release tool and removed from the coiled tubing so that conventional well tools may be used to remove the emergency release tool and a bottom hole assembly attached thereto from the well.

56. The emergency release tool of claim 54, further including means for sealing individual conductors within the conductor cable from drilling fluid being circulated through the tool.

57. The emergency release tool of claim 56, wherein the conductor sealing means includes:

an anchor, an armor nut, a conductor cable sealing connector, and a flow tube;

the anchor being received within the coiled tubing and removably connected to the armor nut;

the anchor and the armor nut having cooperating inclined surfaces for holding an armor portion of the conductor cable;

the conductor cable sealing connector having a plurality of longitudinal bores extending therethrough and including a carrier plug, a composite seal, and a follower plug, the composite seal being disposed between the carrier plug and the follower plug, and each of the individual conductors passing through one of the plurality of longitudinal bores; and

,

a first end of the flow tube being connected to the armor nut to compress the sealing connector between a shoulder on the flow tube and a shoulder on the armor nut and to compress the composite seal and seal the individual conductors from the drilling fluid, and a second end of the flow tube being received within a longitudinal bore of the inner mandrel.

58. The emergency release tool of claim 57, wherein the conductor cable may be remotely detached from the tool by shearing the armor from between the anchor and the armor nut and removed from the coiled tubing so that conventional well tools may be used to remove the emergency release tool and a bottom hole assembly attached thereto from the well.

59. The emergency release tool of claim 32, wherein the tool releases the coiled tubing in a nondestructive manner so as to leave no enlarged diameters areas on the tubing that could interfere with removal of the coiled tubing from a well.

60. The emergency release tool of claim 32, wherein, upon activation of the remotely activated means to disengage the coiled tubing from the tool, no part of a conductor sealing means within the tool is larger than an outer diameter of the coiled tubing, so that removal of the conductor sealing means from the tool will not interfere with removal of the coiled tubing from a well.

61. The emergency release tool of claim 32, wherein the coiled tubing is released from the tool solely by remote activation of the remotely activated means without mechanical manipulation of the emergency release tool by a well tool.

62. The emergency release tool of claim 32, wherein the coiled tubing is released from the tool solely by remote activation of the remotely activated means without movement of the coiled tubing.

63. The emergency release tool of claim 32, wherein the coiled tubing is released from the tool solely by remote activation of the remotely activated means without movement of a bottom hole assembly connected to the emergency release tool.

64. The emergency release tool of claim 32, wherein the coiled tubing need only be deburred to be installed adjacent the releasable slip.

65. The emergency release tool of claims 32, wherein the annular recess in the lower housing may function as a redundant fishing profile for engaging a well tool to be used in retrieving the emergency release tool and a bottom hole assembly attached thereto upon the coiled tubing being released from the emergency release tool and upon detachment of the lower housing from the remainder of the emergency release tool.

66. The emergency release tool of claim 32, wherein the lower housing further includes an annular load bearing shoulder that may function as a redundant fishing profile for engaging a well tool to be used in retrieving the emergency release tool and a bottom hole assembly attached thereto upon the coiled tubing being released from the emergency release tool and upon detachment of the lower housing from the remainder of the emergency release tool.

67. The emergency release tool of claim 32, wherein a quick disconnect coupler is attached to a second end of the lower housing, the quick disconnect coupler including a pin connector having a series of lugs, a box connector for receiving the pin connector and having a series of recesses to engage and hold the lugs, a rigid spacer between the box and pin connectors for transmitting operating loads through the connection, and an integral sealing means for maintaining a fluidic pressure seal between the pin and box connectors.