HIGH DEGREE OF FREEDOM RISER TENSIONER SYSTEM
A riser tensioner system has a riser support device, an actuator, and a bearing assembly disposed between the riser support device and the actuator. The bearing assembly is configured to provide at least five degrees of freedom of movement of the riser support device relative to the actuator.
Embodiments described herein relate to systems and methods of providing flexible connections in riser tensioner systems.
BACKGROUNDSome riser tensioner systems comprise bearings configured to allow relative cocking motions between riser tensioner system components.
Referring to
The lower bearing assemblies 122 comprise a high capacity laminate (HCL) lower spherical bearing stack 126 comprising a series of stacked spherical shell segment shaped elastomeric elements and complementarily shaped nonelastomeric shims. The bearing stack is disposed between a convex mount 128 coupled to the deck 112 and a concave mount 130 coupled to a lower end of the actuator 120. The lower spherical bearing stacks 126 allow relative cocking motions between the convex mount 128 and the concave mount 130, and hence, relative cocking motions between the deck 112 and the actuator 120.
The HDOF bearing assemblies 124 comprise HDOF spherical bearing stacks 132 substantially similar to lower spherical bearing stacks 126. The HDOF bearing assemblies 124 also comprise a convex mount 134 and a concave mount 136. The HDOF spherical bearing stack 132 is disposed between the convex mount 134 and the concave mount 136. In this embodiment, the convex mount 134 is disposed between the actuator 120 and the HDOF spherical bearing stack 132. In this embodiment, the HDOF spherical bearing stack 132 is configured to allow relative cocking motions between the convex mount 134 and the concave mount 136, and hence, between the actuator 120 and the riser 108 via the riser support device 118. The HDOF bearing assemblies 124 further comprise a plate mount 138 and a planar bearing stack 140 disposed between the plate mount 138 and the concave mount 136. Similar to the HDOF spherical bearing stack 132, the planar bearing stack 140 comprises an HCL bearing stack comprising a series of stacked elastomeric elements and nonelastomeric shims, however, the elastomeric elements and nonelastomeric shims of the planar bearing stack 140 are substantially plate-like and are generally flat. The planar bearing stacks 140 are configured to allow translational movement of the plate mounts 138 relative to the concave mount 136.
Accordingly, through the combined utilization of the HDOF spherical bearing stack 132 and planar bearing stack 140, the HDOF bearing assembly 124 allow enables a six degree of freedom connection between the actuator 120 and the riser 108. More specifically, in some embodiments, the HDOF spherical bearing stack 132 allows for three degrees of freedom, such as the pitch, yaw, and roll of the cocking offset movements while the planar bearing stack 140 allows for two additional degrees of freedom in forward-backward and left-right substantially planar translational movements. The sixth degree of freedom of upward-downward movements, in some embodiments, is provided primarily by the lengthening and/or shortening of the actuators 120 and secondarily by the somewhat compressible nature of the HDOF spherical bearing stacks 132 and the planar bearing stacks 140, alternatively referred to as first bearing stacks and second bearing stacks, respectively.
Referring now to
Other embodiments of the current invention will be apparent to those skilled in the art from a consideration of this specification or practice of the invention disclosed herein. Thus, the foregoing specification is considered merely exemplary of the current invention with the true scope thereof being defined by the following claims.
Claims
1. A riser tensioner system (114), comprising:
- a riser support device (118);
- an actuator (120); and
- a high degree of freedom (HDOF) bearing assembly (124) disposed between the riser support device (118) and the actuator (120), the HDOF bearing assembly (124) being configured to provide at least five degrees of freedom of movement of the riser support device (118) relative to the actuator (120).
2. The riser tensioner system (114) of claim 1, wherein the HDOF bearing assembly (124) comprises at least two bearing stacks (132, 140).
3. The riser tensioner system (114) of claim 2, wherein at least one of the two bearing stacks comprises a HDOF spherical bearing stack (132).
4. The riser tensioner system (114) of claim 3, wherein the HDOF spherical bearing stack (132) allows a relative cocking motion.
5. The riser tensioner system (114) of claim 2, wherein at least one of the two bearing stacks comprises a planar bearing stack (140).
6. The riser tensioner system (114) of claim 5, wherein the planar bearing stack (140) allows a relative translational motion.
7. The riser tensioner system (114) of claim 2, wherein the at least two bearing stacks (132, 140) comprise a HDOF spherical bearing stack (132) configured to allow a relative cocking motion and planar bearing stack (140) configured to allow a relative translational motion.
8. An offshore hydrocarbon production system (100), comprising:
- a riser tensioner system (114), comprising: a riser support device (118); an actuator (120); and a high degree of freedom (HDOF) bearing assembly (124) disposed between the riser support device (118) and the actuator (120), the HDOF bearing assembly (124) being configured to provide at least five degrees of freedom of movement of the riser support device (118) relative to the actuator (120).
9. The riser tensioner system (114) of claim 8, wherein the HDOF bearing assembly (124) comprises at least two bearing stacks (132, 140).
10. The riser tensioner system (114) of claim 9, wherein at least one of the two bearing stacks comprises a HDOF spherical bearing stack (132).
11. The riser tensioner system (114) of claim 10, wherein the HDOF spherical bearing stack (132) allows a relative cocking motion.
12. The riser tensioner system (114) of claim 9, wherein at least one of the two bearing stacks comprises a planar bearing stack (140).
13. The riser tensioner system (114) of claim 12, wherein the planar bearing stack (140) allows a relative translational motion.
14. The riser tensioner system (114) of claim 9, wherein the at least two bearing stacks (132, 140) comprise a HDOF spherical bearing stack (132) configured to allow a relative cocking motion and planar bearing stack (140) configured to allow a relative translational motion.
15. A method of providing six degrees of freedom of movement between a riser (108) of an offshore hydrocarbon production system (100) and a platform (102), comprising:
- disposing a high degree of freedom (HDOF) bearing assembly (124) between a riser (108) and an actuator (120), the HDOF bearing assembly (124) comprising at least two bearing stacks (132, 140).
16. The method of claim 15, wherein at least one of the two bearing stacks comprises a HDOF spherical bearing stack (132).
17. The method of claim 16, wherein the HDOF spherical bearing stack (132) allows a relative cocking motion.
18. The method of claim 15, wherein at least one of the two bearing stacks comprises a planar bearing stack (140).
19. The method of claim 18, wherein the planar bearing stack (140) allows a relative translational motion.
20. The method of claim 15, wherein the at least two bearing stacks (132, 140) comprise a HDOF spherical bearing stack (132) configured to allow a relative cocking motion and planar bearing stack (140) configured to allow a relative translational motion.
Type: Application
Filed: Aug 29, 2016
Publication Date: Jun 13, 2019
Inventors: Peter JONES (Erie, PA), Zachary FUHRER (Erie, PA), Jonathan OWENS (Chapel Hill, NC), Gregg CUNE (Conroe, TX)
Application Number: 16/323,115