Vessel mooring system and method for its installation

• US 4,701,143 A
• Filed: 04/29/1986
• Issued: 10/20/1987
• Est. Priority Date: 10/17/1984
• Status: Expired due to Fees

• Current Assignee: Key Ocean Services Incorporated
• Original Assignee: Key Ocean Services Incorporated
• Inventors: Key, Joe W., Shumaker, Fred E.
• Primary Examiner(s): Peters, Jr., Joseph F.
• Assistant Examiner(s): Bartz, Clifford T.
• Application Number:
  US06/857,041
• Time in Patent Office: 539 Days
• Field of Search: 441/3, 441/5, 441/133, 114/264, 114/230, 114/144 B, 114/293, 405/202, 166/355, 166/356, 166/350, 175/7
• US Class Current: 441/5
• CPC Class Codes: B63B 21/507 with mooring turrets

Abstract

The present invention provides a vessel mounted mooring system and a method for its installation. The method involves the construction of a vertical well in the vessel extending from the deck through the bottom plates of the vessel. A lower bearing ring which circumscribes the well is connected to the underside of the bottom plates. A lower turret unit is laterally guided by the lower bearing ring and is restrained against uplift forces by the lower bearing ring. A middle turret unit is placed into the well and connected to the lower turret unit. An upper bearing ring which circumscribes the well is mounted to the deck. The upper turret unit is connected to the middle turret unit whereupon the weight of the assembly of the upper, middle and lower turret units is supported by the upper turret unit and is guided by the upper bearing ring. Chain lockers which include chains and windlasses are mounted to the upper turret unit for selectively paying out or reeling in chain through the upper, middle and lower turret unit to allow the chain to be connected near the subsea floor.

Claims

1. A method of installing a mooring system in newly constructed vessels and retrofitting into existing vessels, comprising:

installing a vertical well extending from the deck of the vessel to the bottom plates of the vessel, the ratio of the opening of the well to the width of the deck adjacent said well being in the ratio of 1;

5 to 1;

10,

connecting a lower bearing ring adjacent to the underside of said bottom plates said lower bearing ring circumscribing said well;

placing a lower turret unit substantially within said lower bearing ring, said lower turret unit having an annular shape with a larger cross-sectional area, in a plane perpendicular to the longitudinal axis of said well, than said well, said lower turret unit rotatably mounted to said lower bearing ring for lateral guidance and prevention of uplift of said lower turret unit in a direction from said bottom plates to said deck;

placing a middle turret unit substantially within said well;

connecting said middle turret unit to said lower turret unit;

connecting an upper bearing ring adjacent to the top of the deck, said upper bearing ring circumscribing said well; and

connecting an upper turret unit to said middle turret unit, said upper turret unit having an annular shape with a larger cross-sectional area, in a plane perpendicular to the longitudinal axis of said well, than said well, said upper turret unit rotatably mounted to said upper bearing ring for lateral guidance thereof and for support of the weight of the assembly of said upper, middle and lower turret units;

whereupon the vessel can be continuously moored in seas having wave heights as great as ninety to one hundred feet.

2. The method of claim 1 wherein the installation of said lower bearing ring further includes the step of:

mounting a first continuous annular ring adjacent to the bottom plates of said deck, said first continuous annular ring circumscribing said well and having a bearing surface disposed in substantial concentric alignment to said well.

3. The method of claim 2 wherein installing said lower turret unit further includes the step of:

installing a plurality of first bearing pads to the outer periphery of said lower turret unit said first bearing pads disposed substantially concentrically to said first continuous annular ring, thereby allowing said lower turret unit to rotate with respect to said lower bearing ring while being guided by said lower bearing ring due to the interaction of said first continuous annular ring and said first bearing pads.

4. The method of claim 3 wherein installation of said upper bearing ring further includes the step of:

mounting a second continuous annular ring adjacent to said deck, said second continuous annular ring circumscribing said well and disposed in a plane substantially perpendicular to the longitudinal axis of said well.

5. The method of claim 4 wherein installation of said upper turret unit further includes the step of:

installing a plurality of second bearing pads adjacent to the lowermost surface of said upper turret unit, said second bearing pads disposed in a plane substantially parallel to said second continuous annular ring and in running contact therewith, thereby allowing the assembly of said upper, lower, and middle turret units to be supported from and rotate with respect to said deck.

6. The method of claim 5 wherein installation of said upper bearing ring further includes the step of:

installing a third continuous annular ring secured adjacent said deck, said third continuous annular ring disposed in substantial concentric alignment to said well while circumscribing said well.

7. The method of claim 6 wherein installation of said upper turret unit further includes the step of:

installing a plurality of third bearing pads to said upper turret unit substantially concentrically to said third continuous annular ring, thereby providing lateral guidance to said upper turret unit due to the interaction of said third continuous bearing ring and said third bearing pads while allowing said upper turret unit to rotate with respect to said deck.

8. The method of claim 7 wherein installation of said lower bearing ring further includes the step of:

installing a fourth continuous annular ring adjacent the bottom plates of said deck, said fourth ring disposed in a plane perpendicular to the longitudinal axis of said well and circumscribing said well.

9. The method of claim 8, wherein installation of said lower turret unit further includes the step of:

installing a plurality of fourth bearing pads adjacent to the topmost surface of said lower turret unit and in a plane substantially parallel to said fourth continuous annular ring, whereupon said lower turret unit is prevented from being uplifted in a direction from said bottom plates to said deck while rotating with respect to said first and fourth continuous annular rings.

10. The method of claim 9 further includes the steps of:

installing a plurality of chain pipes in said lower, middle, and upper turret units extending substantially in a direction parallel to the longitudinal axis of said well;

installing at least one riser pipe substantially parallel to said chain pipes, said riser pipe extending from said upper turret unit to said lower turret unit; and

wherein the step of connecting said upper turret unit further includes the step of;

installing a plurality of chain drives on said upper turret unit each said chain drive adapted to pay out and reel in a chain through one of said chain pipes for securing the assembly of said upper, middle, and lower turret units to the subsea floor while allowing the vessel to rotate about said upper, middle, and lower turret units.

11. The method of claim 10 further including the step of:

securing a swivel joint onto said upper turret unit said swivel joint in fluid communication with said riser pipe.

12. A method of installing a mooring system in a vessel having a vertical well extending from the deck of the vessel to the bottom plates of the vessel comprising:

connecting a lower bearing ring adjacent to the underside of said bottom plates said lower bearing ring circumscribing said well;

placing a lower turret unit substantially within said lower bearing ring, said lower turret unit having an annular shape with a larger cross-sectional area, in a plane perpendicular to the longitudinal axis of said well, than said well, said lower turret unit rotatably mounted to said lower bearing ring for lateral guidance and prevention of uplift of said lower turret unit in a direction from said bottom plates to said deck;

placing a middle turret unit substantially within said well;

connecting said middle turret unit to said lower turret unit;

connecting an upper bearing ring adjacent to the top of the deck, said upper bearing ring circumscribing said well; and

connecting an upper turret unit to said middle turret unit, said upper turret unit having an annular shape with a larger cross-sectional area, in a plane perpendicular to the longitudinal axis of said well, than said well, said upper turret unit rotatably mounted to said upper bearing ring for lateral guidance thereof and for support of the weight of the assembly of said upper, middle and lower turret units;

mounting a first continuous annular ring adjacent to the bottom plates of said deck, said first continuous annular ring circumscribing said well and having a bearing surface disposed in substantial concentric alignment to said well;

installing a plurality of first bearing pads to the outer periphery of said lower turret unit said first bearing pads disposed substantially concentrically to said first continuous annular ring, thereby allowing said lower turret unit to rotate with respect to said lower bearing ring while being guided by said lower bearing ring due to the interaction of said first continuous annular ring and said first bearing pads;

mounting a second continuous annular ring adjacent to said deck, said second continuous annular ring circumscribing said well and disposed in a plane substantially perpendicular to the longitudinal axis of said well;

installing a plurality of second bearing pads adjacent to the lowermost surface of said upper turret unit, said second bearing pads disposed in a plane substantially parallel to said second continuous annular ring and in running contact therewith, thereby allowing the assembly of said upper, lower, and middle turret units to be supported from and rotate with respect to said deck;

installing a third continuous annular ring secured adjacent said deck, said third continuous annular ring disposed in substantial concentric alignment to said well while circumscribing said well;

installing a plurality of third bearing pads to said upper turret unit substantially concentrically to said third continuous annular ring, thereby providing lateral guidance to said upper turret unit due to the interaction of said third continuous bearing ring and said third bearing pads while allowing said upper turret unit to rotate with respect to said deck;

installing a fourth continuous annular ring adjacent the bottom plates of said deck, said fourth ring disposed in a plane perpendicular to the longitudinal axis of said well and circumscribing said well;

installing a plurality of fourth bearing pads adjacent to the topmost surface of said lower turret unit and in a plane substantially parallel to said fourth continuous annular ring, whereupon said lower turret unit is prevented from being uplifted in a direction from said bottom plates to said deck while rotating with respect to said first and fourth continuous annular rings;

installing a plurality of chain pipes in said lower, middle, and upper turret units extending substantially in a direction parallel to the longitudinal axis of said well;

installing at least one riser pipe substantially parallel to said chain pipes, said riser pipe extending from said upper turret unit to said lower turret unit; and

wherein the step of connecting said upper turret unit further includes the step of;

installing a plurality of chain drives on said upper turret unit each said chain drive adapted to pay out and reel in a chain through one of said chain pipes for securing the assembly of said upper, middle, and lower turret units to the subsea floor while allowing the vessel to rotate about said upper, middle, and lower turret units;

securing a swivel joint onto said upper turret unit said swivel joint in fluid communication with said riser pipe;

addition of a plurality of arcuate wear surfaces extending from substantially the top to substantially the bottom of said lower turret unit, each chain extending through a chain pipe and guided through said lower turret unit by contact with one of said arcuate wear surfaces; and

installation of said upper turret unit further includes the steps of;

installing a gear on said upper turret unit;

installing a deck mounted motor driven gear to engage said gear on said upper turret unit thereby causing the vessel to weathervane about an anchored upper turret unit.

13. A vessel mooring system for newly constructed vessels and for retrofitting on existing vessels, said vessels having a deck, bottom plates, a well extending substantially vertically from said deck to said bottom plates below the vessel'"'"'s water line comprising:

a lower turret unit rotatably mounted below said bottom plates, said lower turret unit having an annular shape with a larger cross-sectional area in a plane substantially perpendicular to the longitudinal axis of said well, than said well;

lower bearing means circumscribing said well and extending below said bottom plates for laterally guiding said lower turret unit and for counteracting uplift forces on said lower turret unit in a direction from said bottom plates toward said deck, said lower bearing means connected to said bottom plates of said vessel;

a middle turret unit connected to the top of said lower turret unit and disposed substantially within said well, said middle turret unit having a substantially smaller cross-sectional area than the cross-sectional area of said lower turret unit in a plane perpendicular to the longitudinal axis of said well;

the ratio of the opening of said well to the width of the deck adjacent said well being in the range of 1;

5 to 1;

10,

an upper turret unit connected to said middle turret unit and disposed substantially above said deck of said vessel, said upper turret unit having an annular shape with a larger cross-sectional area in a plane perpendicular to the longitudinal axis of said well, than said well; and

upper bearing means mounted to the top of said deck circumscribing said well for supporting the weight of the connected assembly of said upper, middle, and lower turret units above said deck and laterally guiding said upper turret unit;

whereupon the vessel can be moored in seas having wave heights as great as ninety to one hundred feet.

14. The vessel mooring system of claim 13 further comprising:

mooring means extending through said upper, middle and lower turret units for anchoring said vessel to the bottom of a body of water.

15. The vessel mooring system of claim 14 wherein said lower bearing means further comprises:

a first continuous annular ring mounted adjacent the bottom plates of said deck, said first continuous annular ring circumscribing said well and having a bearing surface disposed in substantial concentric alignment to said well.

16. The vessel mooring system of claim 15 wherein said lower turret unit further comprises:

a plurality of first bearing pads mounted to the outer periphery of said lower turret unit said first bearing pads disposed substantially concentrically to said first continuous annular ring, thereby allowing said lower turret unit to rotate with respect to said lower bearing means while being guided by said lower bearing means due to the interaction of said first continuous annular ring and said first bearing pads.

17. The vessel mooring system of claim 16 wherein said upper bearing means further comprises:

a second continuous annular ring adjacent said deck, said second continuous annular ring circumscribing said well and disposed in a plane substantially perpendicular to the longitudinal axis of said well.

18. The vessel mooring system of claim 17 wherein said upper turret unit further comprises:

a plurality of second bearing pads mounted adjacent to the lowermost surface of said upper turret unit, said second bearing pads disposed in a plane substantially parallel to said second continuous annular ring and in running contact therewith, thereby allowing the assembly of said upper, lower, and middle turret units to be supported from and rotate with respect to said deck.

19. The vessel mooring system of claim 18 wherein said upper bearing means further comprises:

a third continuous annular ring secured adjacent said deck, said third continuous annular ring disposed in substantial concentric alignment to said well while circumscribing said well.

20. The vessel mooring system of claim 19 wherein said upper turret unit further comprises:

a plurality of third bearing pads mounted to said upper turret unit substantially concentrically to said third continuous annular ring, thereby providing lateral guidance to said upper turret unit due to the interaction of said third continuous annular ring and said third bearing pads while allowing said upper turret unit to rotate with respect to said deck.

21. The vessel mooring system of claim 20 wherein said lower bearing means further comprises:

a fourth continuous annular ring adjacent the bottom plates, said fourth ring disposed in a plane perpendicular to the longitudinal axis of said well and circumscribing said well.

22. The vessel mooring system of claim 21, wherein said lower turret unit further comprises:

a plurality of fourth bearing pads adjacent to the topmost surface of said lower turret unit and in a plane substantially parallel to said fourth continuous annular ring, whereupon said lower turret unit is prevented from being uplifted in a direction from said bottom plates to said deck while rotating with respect to said first and fourth continuous annular rings.

23. The vessel mooring system of claim 22 further comprises:

a plurality of chain pipes in said lower, middle, and upper turret units extending substantially in a direction parallel to the longitudinal axis of said well;

at least one riser pipe substantially parallel to said chain pipes, said riser pipe extending from said upper turret unit to said lower turret unit; and

a plurality of chain drives on said upper turret unit each said chain drive adapted to pay out and reel in a chain through one of said chain pipes for securing the assembly of said upper, middle, and lower turret units to the subsea floor while allowing the vessel to rotate about said upper, middle, and lower turret units.

24. The vessel mooring system of claim 23 further comprising:

a swivel joint mounted to said upper turret unit said swivel joint in fluid communication with said riser pipe.

25. A vessel mooring system for a vessel having a deck, bottom plates, a well extending substantially vertically from said deck to said bottom plates below the vessel'"'"'s water line comprising:

a lower turret unit rotatably mounted below said bottom plates, said lower turret unit having an annular shape with a larger cross-sectional area in a plane substantially perpendicular to the longitudinal axis of said well, than said well;

lower bearing means circumscribing said well and extending below said bottom plates for laterally guiding said lower turret unit and for counteracting uplift forces on said lower turret unit in a direction from said bottom plates toward said deck, said lower bearing means connected to said bottom plates of said vessel;

a middle turret unit connected to the top of said lower turret unit and disposed substantially within said well, said middle turret unit having a substantially smaller cross-sectional area than the cross-sectional area of said lower turret unit in a plane perpendicular to the longitudinal axis of said well;

an upper turret unit connected to said middle turret unit and disposed substantially above said deck of said vessel, said upper turret unit having an annular shape with a large cross-sectional area in a plane perpendicular to the longitudinal axis of said well, than said well; and

upper bearing means mounted to the top of said deck circumscribing said well for supporting the weight of the connected assembly of said upper, middle, and lower turret units above said deck and laterally guiding said upper turret unit;

mooring means extending through said upper, middle and lower turret units for anchoring said vessel to the bottom of a body of water;

said lower bearing means further comprises;

a first continuous annular ring mounted adjacent the bottom plates of said deck, said first continuous annular ring circumscribing said well and having a bearing surface disposed in substantial concentric alignment to said well;

said lower turret unit further comprises;

a plurality of first bearing pads mounted to the outer periphery of said lower turret unit said first bearing pads disposed substantially concentrically to said first continuous annular ring, thereby allowing said lower turret unit to rotate with respect to said lower bearing means while being guided by said lower bearing means due to the interaction of said first continuous annular ring and said first bearing pads;

said upper bearing means further comprises;

a second continuous annular ring adjacent said deck, said second continuous annular ring circumscribing said well and disposed in a plane substantially perpendicular to the longitudinal axis of said well;

said upper turret unit further comprises;

a plurality of second bearing pads mounted adjacent to the lowermost surface of said upper turret unit, said second bearing pads disposed in a plane substantially parallel to said second continuous annular ring and in running contact therewith, thereby allowing the assembly of said upper, lower, and middle turret units to be supported from and rotate with respect to said deck;

said upper bearing means further comprises;

a third continuous annular ring secured adjacent said deck, said third continuous annular ring disposed in substantial concentric alignment to said well while circumscribing said well;

said upper turret unit further comprises;

a plurality of third bearing pads mounted to said upper turret unit substantially concentrically to said third continuous annular ring, thereby providing lateral guidance to said upper turret unit due to the interaction of said third continuous annular ring and said third bearing pads while allowing said upper turret unit to rotate with respect to said deck;

said lower bearing means further comprises;

a fourth continuous annular ring adjacent the bottom plates, said fourth ring disposed in a plane perpendicular to the longitudinal axis of said well and circumscribing said well;

said lower turret unit further comprises;

a plurality of fourth bearing pads adjacent to the topmost surface of said lower turret unit and in a plane substantially parallel to said fourth continuous annular ring, whereupon said lower turret unit is prevented from being uplifted in a direction from said bottom plates to said deck while rotating with respect to said first and fourth continuous annular rings;

a plurality of chain pipes in said lower, middle, and upper turret units extending substantially in a direction parallel to the longitudinal axis of said well;

at least one riser pipe substantially parallel to said chain pipes, said riser pipe extending from said upper turret unit to said lower turret unit; and

a plurality of chain drives on said upper turret unit each said chain drive adapted to pay out and reel in a chain through one of said chain pipes for securing the assembly of said upper, middle, and lower turret units to the subsea floor while allowing the vessel to rotate about said upper, middle, and lower turret units;

a swivel joint mounted to said upper turret unit said swivel joint in fluid communication with said riser pipe;

said lower turret unit further comprises;

arcuate wear surfaces extending from substantially the top to substantially the bottom of said lower turret unit, each chain extending through a chain pipe and guided through said lower turret unit by contact with one of said arcuate wear surfaces;

said upper turret unit further comprising, a first gear; and

a second gear secured to said deck and operably connected to said first gear for weathervaning the vessel when said assembly of said upper, middle and lower turret units is anchored to the subsea floor.