Claims
- 1. A taut leg bow mooring system comprising:
- an anchor having a total weight sufficient to remain fixed on the water body floor under predetermined maximum riser line tension, said anchor positionable on the sea floor;
- a riser line secured to and extending from the anchor;
- a submerged buoy secured to an upper end of the riser line, said submerged buoy positioned substantially below the surface of the water body both when the mooring system is connected to a vessel and when said mooring system is not connected to a vessel, said submerged buoy having a first predetermined buoyancy sufficient to maintain the riser line in tension and in a substantially vertical position when said mooring system is not connected to a vessel, thereby minimizing flexure wear of a lower portion of the riser line;
- a floating connector line having a proximate end secured to the submerged buoy and extending therefrom; and
- a surface buoy positioned on the surface of the water and having a second predetermined buoyancy sufficient to prevent submergence of the surface buoy at a maximum vessel offset, said surface buoy secured to a distal end of the floating connector line remote from the submerged buoy, said surface buoy adapted to float on the surface of the water body.
- 2. The taut leg mooring system of claim 1 further including:
- a hawser connected to and extending from a distal end of the connector line secured to the surface buoy, said hawser for connection to a vessel to be moored.
- 3. The taut leg mooring system of claim 1 further including:
- a first length of chain positioned between the anchor and riser wire, said chain having a proximal end connected to the anchor and a distal end connected to the riser wire, wherein said chain reduces flexure in the riser wire.
- 4. The taut leg mooring system of claim 3 having a buoyancy of the submerged buoy around 10 to 20 kips above the combined weight of the riser line and first length of chain.
- 5. The taut leg mooring system of claim 1 further including:
- a second length of chain positioned between the riser wire, and the submerged buoy, said chain having a proximal end connected to the riser wire and a distal end connected to the submerged buoy, wherein said chain reduces flexure in the riser wire.
- 6. The taut leg mooring system of claim 5 having a buoyancy of the submerged buoy around 10 to 20 kips above the combined weight of the riser line, the first length of chain and the second length of chain.
- 7. The taut leg mooring system of claim 1 having at least a 2 to 1 ratio of buoyancy of the surface buoy to the bouyancy of the submerged buoy.
- 8. The taut leg mooring system of claim 1 wherein the anchor has a submerged weight of between about 60 and about 75 tons.
- 9. The taut leg mooring system of claim 1 wherein the system has a stiffness factor of about 450 pounds per foot, said stiffness factor being defined as the increase in bow mooring tension per unit of boat displacement.
- 10. The taut leg mooring system of claim 1 wherein the submerged buoy is positioned about 100 feet below the surface of the water to isolate said submerged buoy and riser line from surface wave action.
- 11. A taut leg bow mooring system comprising:
- an anchor having a total weight sufficient to remain fixed on the water body floor under predetermined maximum riser line tension, said anchor positionable on the sea floor;
- a riser line secured to and extending from the anchor;
- a submerged buoy secured to an upper end of the riser line, said submerged buoy positioned substantially below the surface of the water body both when the mooring system is connected to a vessel and when said mooring system is not connected to a vessel, said submerged buoy having a first predetermined buoyancy around 10 to 20 kips above the weight of the riser line, said first predetermined bouyancy sufficient to maintain the riser line in tension and in a substantially vertical position when said mooring system is not connected to a vessel;
- a connector line having a proximate end secured to the submerged buoy and extending therefrom; and
- a surface buoy positioned on the surface of the water and having a second predetermined buoyancy sufficient to prevent submergence of the surface buoy at a maximum vessel offset, said surface buoy secured to a distal end of the connector line remote from the submerged buoy, said surface buoy adapted to float on the surface of the water body.
- 12. A taut leg bow mooring system comprising:
- an anchor having a total weight sufficient to remain fixed on the water body floor under predetermined maximum riser line tension, said anchor positionable on the sea floor;
- a riser line secured to and extending from the anchor;
- a submerged buoy secured to an upper end of the riser line, said submerged buoy positioned substantially below the surface of the water body both when the mooring system is connected to a vessel and when said mooring system is not connected to a vessel, said submerged buoy having a first predetermined buoyancy sufficient to maintain the riser line in tension and in a substantially vertical position when said mooring system is not connected to a vessel;
- a connector line having a proximate end secured to the submerged buoy and extending therefrom;
- a surface buoy positioned on the surface of the water and having a second predetermined buoyancy sufficient to prevent submergence of the surface buoy at a maximum vessel offset, said surface buoy secured to a distal end of the connector line remote from the submerged buoy, said surface buoy adapted to float on the surface of the water body; and
- having a ratio of buoyancy of the surface buoy to the ratio of the bouyancy of the submerged buoy of at least 2 to 1.
- 13. A taut leg bow mooring system comprising:
- an anchor having a total weight sufficient to remain fixed on the water body floor under predetermined maximum riser line tension, said anchor positionable on the sea floor;
- a riser line secured to and extending from the anchor;
- a submerged buoy secured to an upper end of the riser line, said submerged buoy positioned substantially below the surface of the water body both when the mooring system is connected to a vessel and when said mooring system is not connected to a vessel, said submerged buoy having a first predetermined buoyancy sufficient to maintain the riser line in tension and in a substantially vertical position when said mooring system is not connected to a vessel, thereby minimizing flexure wear of a lower portion of the riser line;
- a floating connector line having a proximate end secured to the submerged buoy and extending therefrom; and
- a surface buoy positioned on the surface of the water and having a second predetermined buoyancy sufficient to prevent submergence of the surface buoy at a maximum vessel offset, said surface buoy secured to a distal end of the floating connector line remote from the submerged buoy, said surface buoy adapted to float on the surface of the water body.
- 14. The taut leg mooring system of claim 13 further including:
- a hawser connected to and extending from the surface buoy, said hawser for connection to a vessel to be moored.
- 15. The taut leg mooring system of claim 13 wherein the anchor has a submerged weight of between about 60 and about 75 tons.
- 16. The taut leg mooring system of claim 13 wherein the anchor is a clump weight type anchor.
- 17. The taut leg mooring system of claim 13 further including:
- a length of chain positioned between the anchor and riser wire, said chain having a proximal end connected to the anchor and a distal end connected to the riser wire, wherein said chain reduces flexure in the riser wire.
- 18. The taut leg mooring system of claim 13 further including:
- a length of chain positioned between the riser wire and the submerged buoy, said chain having a proximal end connected to the riser wire and a distal end connected to the submerged buoy, wherein said chain reduces flexure in the riser wire.
- 19. The taut leg mooring system of claim 13 wherein the system has a stiffness factor of about 450 pounds per foot, said stiffness factor being defined as the increase in bow mooring tension per unit of boat displacement.
- 20. The taut leg mooring system of claim 13 wherein the submerged buoy is positioned about 100 feet below the surface of the water to isolate said submerged buoy and riser line from surface wave action.
RELATED APPLICATION
This application is a continuation application under 37 C.F.R. .sctn.1.53 of application Ser. No. 08/615,120 filed Mar. 21, 1996, abandoned.
US Referenced Citations (11)
Non-Patent Literature Citations (2)
Entry |
Telefax memo from Applicant Aker Marine to Shell Offshore dated May 7, 1991. |
Telefax memo from Applicant Aker Marine to Shell Offshore dated Jun. 17, 1991. |
Continuations (1)
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Number |
Date |
Country |
Parent |
615120 |
Mar 1996 |
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