Rapid deployment mooring and discharge system and method

• US 4,624,645 A
• Filed: 06/27/1985
• Issued: 11/25/1986
• Est. Priority Date: 02/09/1984
• Status: Expired due to Term

• Current Assignee: FMC Technologies Incorporated (TechnipFMC, plc)
• Original Assignee: SOFEC, Inc. (FMC Corporation)
• Inventors: Pedersen, Kristen I., Kiely, Willian L.
• Primary Examiner(s): Barefoot, Galen
• Assistant Examiner(s): Sotelo, Jesus D.
• Application Number:
  US06/749,140
• Time in Patent Office: 516 Days
• Field of Search: 114/230, 114/264, 114/293, 114/294, 441/3-5, 441/28, 441/29, 405/158, 405/162, 405/171, 405/172, 405/173, 405/203, 405/205, 405/207, 405/209, 166/350
• US Class Current: 441/4
• CPC Class Codes: B63B 22/02 specially adapted for mooring a vessel
• CPC Class Codes: B63B 27/34 using pipe-lines anchoring arrangements for special vessels with mooring turrets B63B21/507; buoys specially adapted for mooring a vessel and for transferring fluids, e.g. liquids B63B22/021
• CPC Class Codes: B63B 35/03 Pipe-laying vessels laying pipes under water F16L1/12
• CPC Class Codes: B63B 35/28 Barges or lighters underwater-towed barges B63G8/42; for transporting logs B63B35/62
• CPC Class Codes: F16L 1/165 by towing the pipe on or near the bottom
• CPC Class Codes: F16L 1/203 the pipes being wound spirally prior to laying

Abstract

An offshore bulk liquid discharge system and method for its deployment are disclosed. The system is adapted for rapid deployment and facilitates rapid unloading of liquids from an ocean tanker to a shore location. The system includes a base, a mooring buoy tethered to the base and floodable buoyancy tanks which may be flooded causing the base to land on the sea floor. A product swivel mounted on the base provides fluid communication between a tanker hose and a flexible pipeline.

Claims

1. An offshore bulk liquid discharge system comprising

a base,

buoyancy tank means attached to the base for providing flotation for the system during transportation of the system to a mooring location and adapted for flooding to allow the system to be disposed on the sea floor,

pipeline reel means for holding a coil of flexible pipeline during transportation of the system to a mooring location and for unreeling the flexible pipeline after the system is disposed on the sea floor,

hose reel means for holding a coil of flexible tanker hose during transportation of the system to a mooring location and for unreeling the hose after the system is disposed on the sea floor, and

swivel piping means for rotationally coupling a coil of flexible pipeline held in the pipeline reel means with a coil of tanker hose held in the hose reel means.

2. The system of claim 1 further comprising a mooring buoy means releasably secured to the base, the buoy means being tethered to the base by a flexible securing means attached between the mooring buoy means and the base.

3. The system of claim 2 further comprising releasable securing means having

a support structure means attached to the base,

buoy cradle means connected to the support structure by hinge means,

the buoy cradle means being in an upwardly extending position for connecting releasable buoy cradle bracket means about the buoy means, whereby

after the buoy means is separated from the buoy cradle bracket means, the cradle means may be rotated by the hinge means to a non-vertical position so as to minimize the vertical height of the system.

4. The system of claim 2 wherein the flexible securing means is an anchor chain and further comprising universal joint means connecting the anchor chain to the mooring buoy means and to the base.

5. The system of claim 1 wherein the pipeline reel means and the hose reel means are mounted for rotation about a common axis.

6. The system of claim 5 wherein the pipeline reel means is mounted for rotation on a first slewing ring means disposed on the base and the hose reel means is mounted for rotation on a second slewing ring means disposed on the pipe line reel means.

7. The system of claim 5 wherein the swivel piping means is mounted coaxially with the pipeline reel means and the hose reel means, the swivel piping means comprising

a central section adapted to rotate with the pipeline reel means,

an outer swivel section adapted to rotate independently of the pipeline reel means, and

conduit coupling means for providing fluid communication between a conduit extending from the central section to a coil of flexible pipeline held in the pipeline reel means and the conduit coupling means allowing fluid communication between the outer swivel section and a coil of tanker hose held in the hose reel means.

8. The system of claim 1 wherein the buoyancy tank means comprise

a first buoyancy tank disposed at one end of the base, and

a second buoyancy tank disposed at the other end of the base.

9. A marine bulk liquid discharge system comprising

a base,

a first buoyancy tank mounted at a first end of the base and having means for flooding the first tank,

a second buoyancy tank mounted at a second end of the base and having means for flooding the second tank,

pipeline reel means for holding a coil of flexible pipeline during transportation of the system to a mooring location and for unreeling the flexible pipeline after the system is disposed on the sea floor,

hose reel means for holding a coil of flexible tanker hose during transportation of the system to a mooring location and for unreeling the hose after the system is disposed on the sea floor,

a buoy cradle releasably secured at a first end of the base,

a primary buoy releasably secured in the buoy cradle,

tether means connected between the base and the primary buoy,

first block and tackle means mounted at the buoy cradle and releasably connected to the first end of the base,

first winch means secured to the buoy cradle and operably connected to the first block and tackle means for lowering the first end of the base toward the sea floor,

an auxiliary buoy releasably secured at a second end of the base,

second block and tackle means mounted on the auxiliary buoy and releasably connected to the second end of the base,

second winch means secured to the auxiliary buoy and operably connected to the second block and tackle means for lowering the second end of the base toward the sea floor, and

swivel piping means for rotationally coupling a coil of flexible pipeline held in the pipeline reel means with a coil of tanker hose held in the hose reel means.

10. The system of claim 9 wherein the tether means is an anchor chain and further comprising universal joint means connecting the anchor chain to the primary buoy and the anchor chain to the base.

11. The system of claim 9 wherein the pipeline reel means and the hose reel means are mounted for rotation about a common axis.

12. The system of claim 11 wherein the pipeline reel means is mounted for rotation on a first slewing ring means disposed on the base and the hose reel means is mounted for rotation on a second slewing ring means disposed on the pipeline reel means.

13. The system of claim 11 wherein the swivel piping means is mounted coaxially with the pipeline reel means and the hose reel means, the swivel piping means comprising

a central section adapted to rotate with the pipeline reel means,

an outer swivel section adapted to rotate independently, and

conduit coupling means providing fluid communication between a conduit extending from the central section to a coil of flexible pipeline held in the pipeline reel means and conduit coupling means allowing fluid communication between the outer swivel section and a coil of tanker hose held in the hose reel means.

14. An offshore bulk liquid discharge system comprising

a base,

buoyancy tank means attached to the base for providing flotation for the system during transportation of the system to a mooring location and adapted for flooding to allow the system to be disposed on the sea floor,

hose reel means for holding a coil of flexible tanker hose during transportation of the system to a mooring location and for unreeling the hose after the system is disposed on the sea floor, and

swivel piping means for rotationally coupling a conduit adapted for connection to a pipeline with a coil of tanker hose held in the hose reel means.

15. The system of claim 14 further comprising a mooring buoy means releasably secured to the base, the buoy means being tethered to the base by a flexible securing means attached between the mooring buoy means and the base.

16. The system of claim 15 wherein the flexible securing means is an anchor chain and further comprising universal joint means connecting the anchor chain to the mooring buoy means and to the base.

17. The system of claim 14 wherein the hose reel means is mounted for rotation on a slewing ring means disposed on the base.

18. The system of claim 14 wherein the buoyancy tank means comprise

a first buoyancy tank disposed at one end of the base, and

a second buoyancy tank disposed at the other end of the base.

19. An offshore bulk liquid discharge system comprising,

a base,

buoyancy tank means attached to the base for providing flotation for the system during transportation of the system to a mooring location and adapted for flooding to allow the system to be disposed on the sea floor, wherein the buoyancy tank means comprises,

a first buoyancy tank mounted at a first end of the base and having means for flooding the first tank,

a second buoyancy tank mounted at a second end of the base and having means for flooding the second tank,

a buoy cradle releasably secured at a first end of the base,

a primary buoy releasably secured in the buoy cradle,

tether means connected between the base and the primary buoy,

first block and tackle means mounted at the buoy cradle and releasably connected to the first end of the base,

first winch means secured to the buoy cradle and operably connected to the first block and tackle means for lowering the first end of the base toward the sea floor,

an auxiliary buoy releasably secured at a second end of the base,

second block and tackle means mounted on the auxiliary buoy and releasably connected to the second end of the base, and

coupling means disposed on the base for connecting a pipeline provided between onshore storage facilities and the base and a tanker hose provided between a cargo vessel and the base, wherein the tanker hose comprises tanker hose sections releasably secured to the base of the system and wherein the tanker hose sections have coupling means on each end for connecting the sections end to end into a hose string and for connection of the hose string at one end to a conduit of the coupling means and at its other end to a discharge conduit of a vessel.

20. A method of deployment of an offshore bulk liquid discharge system between a shore location and a tanker comprising the steps of

towing an offshore bulk discharge system to a deployment location, the system having

a base,

buoyancy tank means attached to the base,

pipeline reel means holding a coil of flexible pipeline,

hose reel means holding a coil of flexible tanker hose,

swivel piping means rotationally coupling the coil of flexible pipeline in the pipeline reel means with the coil of tanker hose in the hose reel means and a

mooring buoy releasably connected to the base, the buoy being tethered by a flexible securing means attached between the mooring buoy and the base,

flooding the buoyancy tank means and releasing the secured mooring buoy so that the base sinks and finally rests on the sea floor with the mooring buoy floating on the sea surface while still being tethered to the base of the system,

pulling the end of the coil of flexible pipeline to shore while the pipeline unreels from the pipeline reel means,

pulling the end of the flexible tanker hose to a tanker while the hose unreels from the hose reel means, and

attaching the tanker to the mooring buoy.

21. The method of claim 20 wherein the system buoyancy tank means has

a first buoyancy tank disposed at a first end of the base and

a second buoyancy tank disposed at a second end of the base, and

the steps of flooding the buoyancy tank means and releasing the secured mooring buoy comprise the steps of

releasing the mooring buoy from connection to the base,

flooding the first buoyancy tank and allowing the first end of the system to sink to the sea floor, and

flooding the second buoyancy tank and allowing the second end of the system to sink to the sea floor.

22. The method of claim 20 wherein the step of pulling a flexible pipeline from a submerged pipeline reel means to shore comprises the sub-steps of

attaching a tow line between the end of the flexible pipeline on the submerged pipeline reel means and a towing vessel,

pulling the flexible pipeline as close to shore as operationally possible with the towing vessel,

disconnecting the tow line from the end of the flexible pipeline,

attaching a winch line to the end of the flexible pipeline unspooled about a winch disposed onshore, and

spooling the winch line about the onshore winch until the flexible pipeline is landed onshore.

23. A method of deployment of a marine bulk liquid discharge system between a shore location and tanker comprising the steps of,

towing an offshore bulk discharge system to a deployment location, the system having

a base,

a first buoyancy tank mounted at a first end of the base and having means for flooding the first tank,

a second buoyancy tank mounted at a second end of the base and having means for flooding the second tank,

pipeline reel means holding a coil of flexible pipeline,

hose reel means holding a coil of flexible tanker hose,

a buoy cradle releasably secured at the first end of the base,

a mooring buoy releasably secured in the buoy cradle,

tether means connected between the base and the mooring buoy,

first block and tackle means mounted on the buoy cradle and releasably connected to the first end of the base,

first winch means secured to the buoy cradle and operably connected to the first block and tackle means,

an auxiliary buoy releasably connected at a second end of the base,

second block and tackle means mounted on the auxiliary buoy and releasably connected to the second end of the base,

second winch means mounted on the auxiliary buoy and operably connected to the second block and tackle means, and

swivel piping means for rotationally coupling a coil of flexible pipeline held in the pipeline

reel means with a coil of tanker hose held in the hose reel means,

disconnecting the buoy cradle from its secured connection at the first end of the base,

flooding the first buoyancy tank,

lowering the first end of the base into the sea by means of the first winch means and first block and tackle means until the base is inclined with respect to the surface of the sea,

disconnecting the auxiliary buoy from the second end of the base,

flooding the second buoyancy tank,

lowering the base while substantially in the inclined position into the sea by means of the first winch and block and tackle means and the second winch and block and tackle means until the first end of the base lands on the sea floor,

disconnecting the first block and tackle means from the first end of the base,

lowering the second end of the base by means of the second winch and block and tackle means until the base rests on the sea floor,

disconnecting the second block and tackle means from the second end of the base,

pulling the end of the coil of flexible pipeline to shore while the pipeline unreels from the pipeline reel means,

pulling the end of the flexible tanker hose to a tanker while the hose unreels from the hose reel means, and

attaching the tanker to the mooring buoy.

24. The method of claim 23 wherein the step of pulling a flexible pipeline from a submerged pipeline reel means to shore comprises the steps of

attaching a tow line between the end of the flexible pipeline on the submerged pipeline reel means and a towing vessel,

pulling the flexible pipeline as close to shore as operationally possible with the towing vessel,

disconnecting the tow line from the end of the flexible pipeline,

attaching a winch line to the end of the flexible pipeline unspooled about a winch disposed onshore, and

spooling the winch line about the onshore winch until the flexible pipeline is landed onshore.

25. A method of deploying an offshore bulk liquid discharge system between a shore location and a tanker comprising the steps of

providing an offshore bulk discharge system to a deployment location, the system having

a base,

buoyancy tank means attached to the base,

hose reel means holding a coil of flexible tanker hose,

swivel piping means rotationally coupling a conduit adapted for connection to a pipeline with the coil of tanker hose in the hose reel means, and

a mooring buoy releasably connected to the base, the buoy being tethered by a flexible securing means attached between the mooring buoy and the base,

flooding the buoyancy tank means and releasing the secured mooring buoy so that the base sinks and finally rests on the sea floor with the mooring buoy floating on the sea surface while still being tethered to the base of the system,

providing a pipeline between the conduit coupled to the swivel piping means and an onshore storage facility,

pulling the end of the flexible tanker hose to a tanker while the hose unreels from the hose reel means, and

attaching the tanker to the mooring buoy.

26. The method of claim 25 wherein the system buoyancy tank means has

a first buoyancy tank disposed at a first end of the base and

a second buoyancy tank disposed at a second end of the base, and

the steps of flooding the buoyancy tank means and releasing the secured mooring buoy comprise the steps of

releasing the mooring buoy from connection to the base

flooding the first buoyancy tank and allowing the first end of the system to sink to the sea floor, and

flooding the second buoyancy tank and allowing the second end of the system to sink to the sea floor.

27. A method for deploying an offshore bulk liquid system in which the system has

a base,

a first buoyancy tank mounted at a first end of the base and having means for flooding the first tank,

a second buoyancy tank mounted at a second end of the base and having means for flooding the second tank,

a buoy cradle releasably secured at the first end of the base,

a mooring buoy releasably secured in the buoy cradle,

tether means connected between the base and the mooring buoy,

first block and tackle means mounted on the buoy cradle and releasably connected to the first end of the base,

first winch means secured to the buoy cradle and operably connected to the first block and tackle means,

an auxiliary buoy releasably connected at a second end of the base,

second block and tackle means mounted on the auxiliary buoy and releasably connected to the second end of the base,

second winch means mounted on the auxiliary buoy and operably connected to the second block and tackle means,

the method comprising the steps of

providing the offshore bulk liquid system at an offshore deployment location proximal shore storage facilities,

setting the base of the system on the sea bed at the deployment location,

releasing a mooring buoy releasably secured to the system from the system to float on the sea surface while being tethered to the base of the system,

and wherein the steps of setting the base of the system on the sea floor and releasing a mooring buoy from the system to float on the sea surface while being tethered to the base of the system comprise the substeps of,

disconnecting the buoy cradle from its secured connection at the first end of the base, flooding the first buoyancy tank,

lowering the first end of the base into the sea by means of the first winch means and first block and tackle means until the base is inclined with respect to the surface of the sea,

disconnecting the auxiliary buoy from the second end of the base,

flooding the second buoyancy tank,

lowering the base while substantially in the inclined position into the sea by means of the first winch and block and tackle means and the second winch and block and tackle means until the first end of the base lands on the sea floor,

disconnecting the first block and tackle means from the first end of the base,

lowering the second end of the base by means of the second winch and block and tackle means until the base rests on the sea floor, and

disconnecting the second block and tackle means from the second end of the base,

attaching a tanker to the mooring buoy,

connecting a pipeline to a coupling means disposed on the system, and

connecting a tanker hose between the vessel and the coupling means.

28. A method of deployment of an offshore bulk liquid discharge system between a shore location and a tanker comprising the steps of,

towing an offshore bulk discharge system to a position close to the shore location,

a base,

buoyancy tank means attached to the base,

pipeline reel means carrying a coil of flexible pipeline,

hose reel means carrying a coil of flexible tanker hose,

swivel piping means rotationally coupling the coil of the flexible pipeline in the pipeline reel means with the coil of tanker hose in the hose reel means and a

mooring buoy releasably connected to the base, the buoy being tethered by a flexible securing means attached between the mooring buoy and the base,

attaching a winch line to the end of the flexible pipeline unspooled about a winch disposed onshore,

spooling the winch line about the onshore winch until the flexible pipeline is landed onshore,

towing said bulk discharge system to a deployment location while unspooling the flexible pipeline from said pipeline reel means,

flooding the buoyancy tank means and releasing the secured mooring buoy so that the base sinks until it rests on the sea floor with the mooring buoy floating on the sea surface while still being tethered to the base of the system,

pulling the end of the flexible tanker hose to a tanker while the hose unreels from the hose reel means, and

attaching the tanker to the mooring buoy.

29. The method of claim 28 wherein the system buoyancy tank means has

a first buoyancy tank disposed at a first end of the base, and

a second buoyancy tank disposed at a second end of the base, and

the steps of flooding the buoyancy tank means and releasing the secured mooring buoy comprise the steps of

releasing the mooring buoy from connection to the base,

flooding the first buoyancy tank and allowing the first end of the system to sink to the sea floor, and

flooding the second buoyancy tank and allowing the second end of the system to sink to the sea floor.

30. An offshore bulk liquid discharge system comprising,

a base,

buoyancy tank means attached to the base for providing flotation for the system during transportation of the system to a mooring location and adapted for flooding to allow the system to be disposed on the sea floor,

hose reel means carrying a coil of flexible tanker hose during transportation of the system to a mooring location and for unreeling the hose after the system is disposed on the sea floor,

swivel piping means for rotationally coupling a conduit adapted for connection to a pipeline with a coil of tanker hose held in the hose reel means,

an anchor chain having one end connected to the base, and

secondary buoy means for holding said anchor chain in a substantially vertical position upon deployment of said system on the sea floor in relatively shallow water.

31. The system of claim 30 further comprising a primary buoy means releasably secured to the base, the buoy means being tethered to the base by a flexible securing means attached between the primary buoy means and the base, said primary buoy means adapted operably to moor a tanker in relatively deeper water than said secondary buoy means.

32. The system of claim 30 wherein the hose reel means is mounted for rotation on a slewing ring means disposed on the base.

33. The system of claim 30 wherein the buoyancy tank means comprise

a first buoyancy tank disposed at one end of the base, and

a second buoyancy tank disposed at the other end of the base.

34. A method of deploying an offshore bulk liquid discharge system between a shore location and a tanker comprising the steps of

providing an offshore bulk discharge system to a deployment location, the system having

a base,

buoyancy tank means attached to the base,

hose reel means carrying a coil of flexible tanker hose,

swivel piping means rotationally coupling a conduit adapted for connection to a pipeline with the coil of tanker hose in the hose reel means,

an anchor chain having one end connected to base, and

secondary mooring buoy means connected at the other end of said anchor chain in a substantially vertical position upon deployment of said system on the sea floor in relatively shallow water,

flooding the buoyancy tank means until the base sinks and rests on the sea floor with the secondary mooring buoy means floating on the sea surface while still being connected via said anchor chain to the base of the system,

providing a pipeline between the conduit coupled to the swivel piping means and an onshore storage facility,

pulling the end of the flexible tanker hose to a tanker while the hose unreels from the hose reel means, and

attaching the tanker to the secondary mooring buoy means.

35. The method of claim 34 wherein the system additionally has

a primary buoy means releasably secured to the base, the primary buoy means being tethered to the base by a flexible securing means attached between the primary buoy means and the base, said primary buoy means adapted operably to moore a tanker in relatively deeper water than said secondary mooring buoy means, the method further comprising the steps of

disconnecting the primary buoy means from the system, and

allowing the primary buoy means to float free from the system as the system is deployed on the sea floor.

36. The method of claim 34 wherein the system buoyancy tank means has

a first buoyancy tank disposed at a first end of the base, and

a second buoyancy tank disposed at a second end of the base, and

the step of flooding the buoyancy tank means comprises the sub-steps of

flooding the first buoyancy tank and allowing the first end of the system to sink to the sea floor, and

flooding the second buoyancy tank and allowing the second end of the system to sink to the sea floor.