Claims
- 1. An apparatus for conveying fluids from a subsea location to a surface platform, comprising:
a receptacle adapted to be mounted to a platform, the receptacle having a generally upward facing load shoulder therein; a subsea riser assembly having a supporting shoulder that engages the load shoulder to resist downward pull of the riser assembly; a preload member mounted to the riser assembly, the preload member contacting the receptacle and exerting a preload force on the riser assembly.
- 2. The apparatus according to claim 1, wherein the preload member is mounted to the riser assembly above the supporting shoulder of the riser assembly and exerts a downward preload force on the supporting shoulder.
- 3. The apparatus according to claim 1, wherein the preload member is mounted to the riser assembly below the supporting shoulder and exerts a radial preload force between the riser assembly and the receptacle.
- 4. The apparatus according to claim 1, wherein the preload member comprises:
a downward facing lip formed on an exterior of the riser assembly below the supporting shoulder; a wedging block mounted to the riser assembly below the supporting shoulder for axial movement between an engaged position wedging the lip radially outward into engagement with the receptacle and a disengaged position.
- 5. The apparatus according to claim 4, further comprising:
a hydraulic cylinder for moving the block to the engaged position.
- 6. The apparatus according to claim 4, further comprising:
a downward extending lip mounted on the riser assembly below the supporting shoulder, the lip engaging an inside surface of the receptacle in interference engagement, causing the lip to radially deflect.
- 7. An apparatus for supporting a subsea riser at a surface platform, comprising:
a receptacle adapted to be mounted to a platform, the receptacle having a generally downward facing upper shoulder and a generally upward facing lower shoulder therein; a hanger adapted to be connected to the sub sea riser, the hanger having a supporting shoulder that engages the lower shoulder to resist downward pull of the riser; an upper member that lands in the receptacle above and in contact with the riser; a latch carried by the upper member that engages the upper shoulder to prevent upward movement of the upper member; and the upper member having a tensioner that cooperates with the latch to exert a downward preload force on the supporting shoulder of the hanger.
- 8. The apparatus according to claim 7, wherein the upper member comprises:
an outer member that carries the latch and lands on the hanger; and wherein the tensioner comprises:
an inner member that is carried in the outer member:
a locking surface on the inner member that cooperates with a locking surface on the latch to exert an outward force on the latch and a downward force on the outer member as the inner member is moved downward relative to the outer member.
- 9. The apparatus according to claim 7, wherein the upper member comprises:
an outer member that carries the latch and lands on the hanger; and wherein the tensioner comprises:
an inner member that is carried in the outer member; a set of threads on the inner member that engages a set of threads on the latch to exert an outward force on the latch and a downward force on the outer member as the inner member is rotated relative to the outer member.
- 10. The apparatus according to claim 7, wherein the upper member comprises:
an annular outer member that carries the latch and lands on the hanger; a tubular inner member adapted to joined to a conduit extending upward from the inner member, the inner member being located in the outer member and having abore that is substantially the same diameter as a bore of the hanger, the hanger having an internal shoulder in the bore of the hanger that is located adjacent a lower end of the inner member; and a seal that extends between the lower end of the inner member and the bore of the hanger.
- 11. The apparatus according to claim 7, wherein the supporting shoulder of the hanger comprises a locking member that is outward biased.
- 12. The apparatus according to claim 7, wherein the upper and lower shoulders in the receptacle comprise grooved profiles.
- 13. The apparatus according to claim 7, wherein the latch comprises:
a split ring: and
a plurality of segments on an outer diameter of the ring.
- 14. The apparatus according to claim 7, wherein the latch comprises:
a split ring: and
a plurality of segments carried on an outer diameter of the ring for radial movement relative to the receptacle; and wherein the tensioner comprises:
a set threads on an outer diameter of the ring; and an inner member that has a conical surface with a set of threads that engage the threads on the ring, so that rotational movement of the inner member advances the threads and moves the ring and segments radially outward.
- 15. An apparatus for supporting an upper end of a subsea riser at a surface platform, comprising:
a receptacle adapted to be mounted to a platform, the receptacle having upper and lower grooved profiles therein; a hanger adapted to be connected to the upper end of a subsea riser; a hanger latch that engages the lower grooved profile in the receptacle to resist downward pull of the riser; an outer member that lands on the hanger; an outer member latch carried by the outer member that engages the upper grooved profile; an inner member that is carried in the outer member:
a locking surface on the inner member that cooperates with a locking surface on the outer member latch to exert an outward force on the outer member latch, the engagement of the latch with the upper grooved profile creating a downward force on the outer member as the inner member is moved downward relative to the outer member.
- 16. The apparatus according to claim 15, wherein the locking surfaces comprise threads.
- 17. The apparatus according to claim 15, wherein the outer member latch comprises:
a split ring having an outer diameter and an inner diameter; and a plurality of segments carried on the outer diameter of the ring for radial movement relative to the outer member between engaged and disengaged positions with the upper grooved profile in the receptacle; and wherein the locking surfaces comprise:
a set of threads on the inner diameter of the ring; and a set of threads on an outer diameter of the inner member.
- 18. The apparatus according to claim 15, wherein the locking surface on the outer member latch comprises a conical annular inner surface, and the locking surface on the inner member comprises a mating conical outer surface.
- 19. The apparatus according to claim 15, wherein outer member latch comprises:
a split ring having an outer surface; and a plurality of segments carried on the outer surface of the ring for radial movement relative to the outer member between engaged and disengaged positions with the upper grooved profile in the receptacle; and wherein the locking surfaces comprise:
a tapered inner surface on the ring having a set of threads; and a tapered outer surface on the inner member having a set of threads.
- 20. The apparatus according to claim 15, wherein the inner member is adapted to be joined to a conduit extending upward from the inner member, the inner member having a bore that is substantially the same diameter as a bore of the hanger, the hanger having an internal shoulder in the bore of the hanger that is located adjacent a lower end of the inner member; and wherein the apparatus further comprises:
a seal that extends between the lower end of the inner member and the bore of the hanger.
- 21. An apparatus for supporting an upper end of a subseariser on a surface platform, comprising:
a receptacle adapted to be mounted to a platform, the receptacle having upper and lower grooved profiles therein; a hanger adapted to be connected to the upper end of a subsea riser; a hanger latch that is outward biased and which engages the lower grooved profile in the receptacle to resist downward pull of the riser; an outer member that has a generally downward facing shoulder that lands on the hanger; an outer member latch carried by the outer member, the outer member latch having an outer portion that engages the upper grooved profile and an inner portion having an inner surface containing a set threads formed along a tapered surface; an inner member that is carried in the outer member, the inner member having a set of threads on a tapered outer surface portion of the inner member that engages the set of threads on the inner portion of the outer member latch to exert an outward force on the outer member latch as the inner member is rotated relative to the outer member; and the outer member latch being dimensioned to be located slightly out of alignment with the upper grooved profile when the outer member initially lands on the hanger, so that outward movement into the upper grooved profile causes a downward preload force to be exerted through the outer member, hanger and hanger latch into the receptacle.
- 22. The apparatus according to claim 21,wherein the hanger has an upper rm onto which the outer member lands.
- 23. The apparatus according to claim 21, wherein the inner member is adapted to be joined to a conduit extending upward from the inner member, the inner member having a bore that is substantially the same diameter as a bore of the hanger, the hanger having an internal shoulder in the bore of the hanger that is located adjacent a lower end of the inner member; and wherein the apparatus further comprises:
a seal that extends between the lower end of the inner member and the bore of the hanger.
- 24. An apparatus for supporting a subsea riser at a surface platform, comprising:
a receptacle adapted to be mounted to a platform, the receptacle having a generally upward facing load shoulder; a hanger adapted to be connected to a subsea riser, the hanger having a supporting shoulder that engages the load shoulder to resist downward pull of the riser; and a downward extending lip mounted to an exterior surface of the hanger below the supporting shoulder, the lip being spaced radially outward from the exterior surface and engaging an inside surface of the receptacle in radial interference fit.
- 25. The apparatus according to claim 24, further comprising:
a wedge member mounted to the hanger for axial movement relative to the riser between an engaged position wedging between the lip and the exterior surface of the riser and a disengaged position.
- 26. The apparatus according to claim 25, further comprising:
a rod extending downward from the wedge member; and a jack mechanism connected between the rod and the hanger for moving the rod axially to move the wedge member between the engaged and disengaged positions.
- 27. The apparatus according to claim 25, further comprising:
a rod extending downward from the wedge member; and a hydraulic cylinder assembly connected between the rod and the hanger for moving the rod axially to move the wedge member between the engaged and disengaged positions.
- 28. The apparatus according to claim 28, wherein the lip has an outer surface with undeflected radial dimension that is greater than an inner diameter of the receptacle for engaging the receptacle in interference fit as the hanger is moved into the receptacle.
- 29. A method of connecting a subsea riser assembly to a surface platform, comprising:
(a) providing a receptacle on the platform with a generally upward facing load shoulder; (b) providing a supporting shoulder on the riser and landing the supporting shoulder on the load shoulder, thereby resisting downward pull by the riser assembly; (c) applying a preload force between the riser assembly and the receptacle to resist movement of the load shoulder on the supporting shoulder.
- 30. The method according to claim 29, wherein step (a) further comprises providing the receptacle with a generally downward facing shoulder above the load shoulder, and step (c) comprises:
applying the preload force downward against the supporting shoulder and load shoulder, and reacting the preload force against the downward facing shoulder.
- 31. The method according to claim 29, wherein step (c) comprises exerting the preload force in radially outward directions at a point below the supporting shoulder and the load shoulder.
- 32. The method according to claim 29, wherein step (c) comprises:
providing a downward extending lip on an exterior of the riser assembly below the supporting shoulder; and forcing the lip into radial engagement with receptacle, causing the lip to deflect and exert a radial preload force.
- 33. The method according to claim 32, further comprising:
pushing a wedging block between the lip and the receptacle to push the lip radially outward.
- 34. A method of connecting a subsea riser to a surface platform, comprising:
(a) providing a receptacle on the platform with a generally upward facing lower shoulder and with a generally downward facing upper shoulder; (b) securing a hanger to an upper end of the riser and landing the hanger on the lower shoulder, thereby resisting downward pull by the riser; (c) providing an upper member with a latch, inserting the upper member into the receptacle into contact with the hanger and engaging the upper shoulder with the latch to prevent upward movement of the upper member in the receptacle; then (d) applying a downward preload force on the upper member and through the upper member and hanger to the lower shoulder, the downward preload force being reacted through the latch against the upper shoulder.
- 35. The method according to claim 34, wherein step (d) comprises:
providing the upper member with an outer member and an inner member and moving the inner member downward relative to the outer member.
- 36. The method according to claim 34, wherein step (d) comprises:
providing the latch with an inner surface containing a set ofthreads, and providing the upper member with an outer member and inner member, the inner member having an outer surface containing a set of threads in engagement with the set of threads of the latch; then rotating the inner member relative to the latch and the outer member, causing the inner member to move downward relative to the outer member.
- 37. The method according to claim 34, firther comprising providing the upper member with a bore that has a diameter the same as a diameter of the hanger, and inserting a seal between a lower end of the bore of the upper member and an upper end of the bore of the hanger.
Parent Case Info
[0001] This invention claims priority from provisional application Ser. No. 60/204,586, filed May 16, 2000 for Connection System for Catenary Riser.
Provisional Applications (1)
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Number |
Date |
Country |
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60204586 |
May 2000 |
US |