Method and apparatus for restraining a tendon top connector in reverse loading conditions
A tendon top connector for a moored, floating structure such as a tension leg platform, a tension leg buoy or the like has a bowl-shaped extension on the member which transfers the tension of the tendon to the flex connector. A dome-shaped structure at least partially surrounds the bowl-shaped extension but is spaced apart from it to permit at least some rotational movement of the connector. The dome-shaped structure may be attached by clamps or other mounting means to a flange member affixed to the tendon porch. This arrangement provides a load path when the tendon top connector is reverse loaded that extends from the tendon length adjustment joint, through slips, through the bowl-shaped extension, through the dome-shaped structure, through the segmented clamps, and finally into a flange attached to the tendon porch. In this way, detachment of the tendon top connector is prevented if a reverse load is applied such as may occur during extreme metocean conditions.
1. A tendon top connector for a moored, floating structure comprising:
a bearing plate having a mating surface for a flex bearing;
a flex bearing having a first surface fitted to the mating surface of the bearing plate and an opposing second surface;
a bowl having a first inclined surface contacting the second surface of the flex bearing, a second inclined surface for mating with one or more slips and a substantially upwardly oriented rim extension on the outer circumference of the bowl; and,
a dome attached to the bearing plate substantially surrounding and spaced apart from the rim extension of the bowl.
2. A tendon top connector as recited in claim 1 wherein the dome is additionally attached to a tendon porch.
3. A tendon top connector as recited in claim 1 further comprising a mating flange connected to the bearing plate and the dome.
4. A tendon top connector as recited in claim 1 wherein the dome is attached to the bearing plate by means of a mating flange attached to the bearing plate.
5. A tendon top connector as recited in claim 4 further comprising a plurality of clamps joining the dome and the mating flange.
6. A tendon top connector as recited in claim 5 wherein the clamps are segments of a circle.
7. A tendon top connector as recited in claim 5 further comprising at least one bolt passing through at least one clamp and into a threaded hole in the mating flange.
8. A tendon top connector as recited in claim 5 wherein the dome has a substantially radial flange sized and spaced to engage the clamps.
9. A tendon top connector as recited in claim 4 further comprising bolts which pass through a hole in the dome and engage a threaded receptacle in the mating flange.
10. A tendon top connector as recited in claim 4 further comprising bolts which pass through a hole in the mating flange and engage a threaded receptacle in the dome.
11. A tendon top connector as recited in claim 4 further comprising bolts which pass through a hole in the dome and a hole in the mating flange and are secured with a threaded nut.
12. A tendon top connector as recited in claim 1 wherein the dome has a substantially circular opening on its upper surface.
13. A tendon top connector as recited in claim 1 wherein the dome comprises a section the inner surface of which is substantially hemispherical.
14. A tendon top connector as recited in claim 1 wherein the dome comprises a substantially cylindrical section and a substantially hemispherical section.
15. A moored, floating structure comprising:
a hull;
at least one tendon for securing the hull to an anchor piling in the sea floor;
at least one tendon connector attached to the hull, said tendon connector comprising:
a bearing plate having a mating surface for a flex bearing;
a flex bearing having a first surface fitted to the mating surface of the bearing plate and an opposing second surface;
a bowl having a first inclined surface contacting the second surface of the flex bearing, a second inclined surface for mating with one or more slips and a substantially upwardly oriented rim extension on the outer circumference of the bowl;
a plurality of slips engaging the at least one tendon and contacting the second inclined surface of the bowl; and,
a dome attached to the bearing plate substantially surrounding and spaced apart from the rim extension of the bowl.
16. A method for restraining the tendon top connector of a tension leg platform in a reverse loading condition comprising:
providing a bearing plate having a mating surface for a flex bearing;
providing a flex bearing having a first surface fitted to the mating surface of the bearing plate and an opposing second surface;
providing a bowl having a first inclined surface contacting the second surface of the flex bearing, a second inclined surface for mating with one or more slips and a substantially upwardly oriented rim extension on the outer circumference of the bowl;
providing a dome attached to the bearing plate substantially surrounding the rim extension of the bowl; and,
contacting the dome with the rim extension of the bowl such that upward movement of the bowl is restricted.