Rapidly installable mooring and cargo system

Abstract

A system which can be set up in emergencies to moor an offloading vessel and transfer oil between it and a seabed pipeline, as to remove oil from a grounded tanker or to deliver fuel to the shore under hostile or emergency conditions. The system includes a barge containing a fluid swivel as well as a mooring buoy and buoy-holding chain. The barge can be towed to a desired location and pipes and hoses connected to the fluid swivel, and the barge then can be sunk to the seabed. Upon sinking, the barge is already connected to the seabed pipeline and to hoses that extend from the barge to the sea surface to connect to an offloading vessel, as well as being connected through a chain to a buoy floating at the sea surface which has a hawser for mooring the vessel. A vessel can be utilized to tow out the seabed pipeline, to facilitate installation of the pipeline as to enable connection of the pipeline to the fluid swivel on the barge prior to sinking the barge.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A rapidly deployable mooring and hydrocarbon transfer system for transferring hydrocarbons between a seabed pipeline and a floating offloading vessel at the sea surface, comprising: a barge having a hull which is buoyant and seaworthy but which can be flooded and sunk and which has a lower surface formed to rest stably on the sea floor, and which has means for anchoring it to the seabed;   a fluid swivel assembly including a stationary swivel portion which is mounted on said barge and which has a first coupling positioned to connect to a largely horizontal seabed pipeline, and including a rotatable swivel portion which has a second coupling positioned to connected to a largely upwardly-extending hose structure that can connect to the offloading vessel, to maintain such connection during unlimited rotation of the vessel, all of said fluid swivel assembly lying at about the same level as the hull of said barge so that the barge with the fluid swivel assemly thereon is seaworthy;   said barge including a buoy with hawser connecting means for connecting to one end of a hawser whose opposite end moors a ship said buoy releasably mounted on said barge, a mooring line chamber, and a mooring line having a majority of its length stored in said chamber and a first line end connected to said barge along the axis of said swivel assembly and a second end connected to said buoy, whereby to enable automatic deployment of a connected buoy upon sinking of the barge.   
     
     
       2. The system described in claim 1 wherein: said barge has a largely horizontal lower surface, and said anchoring means includes spike means extending below the hull for anchoring into the seabed.   
     
     
       3. A method for installing a mooring and fluid transfer system for mooring a ship and transferring fluid to or from the moored ship, comprising: simultaneously towing a barge containing a fluid swivel and an end of a pipeline, to a desired off-shore location;   connecting one end of a hose structure to a rotatable portion of the fluid swivel, and establishing said end of the pipeline in connection with a nonrotatable portion of the fluid swivel;   mounting a buoy on said barge, mounting a flexible line on said barge which is long enough to reach substantially from the seabed to the sea surface at said offshore location, releasing said buoy and line from attachment to said barge, and sinking said barge with the pipeline end and hose structure end attached thereto, in a controlled manner under said buoy and deploying said flexible line from said barge; and   extending a hawser between said buoy and a ship, and connecting said hose structure to said ship. .Iadd.   
     
     
       4.  A rapidly deployable mooring and hydrocarbon transfer system for transferring hydrocarbons between a seabed pipeline and a floating offloading vessel at the sea surface, comprising: a barge having a hull which is buoyant and seaworthy but which can be flooded and sunk and which has a lower surface formed to rest stably on the sea floor;   a fluid swivel assembly including a stationary swivel portion which is mounted on said barge and which has a first coupling positioned to connect to a largely horizontal seabed pipeline, and including a rotatable swivel portion which has a second coupling positioned to connect to a largely upwardly-extending hose structure that can connect to the offloading vessel, to maintain such connection during unlimited rotation of the vessel, all of said fluid swivel assembly lying at about the same level as the hull of said barge so that the barge with the fluid swivel assembly thereon is seaworthy;   said barge including a buoy with hawser connecting means for connecting to one end of a hawser whose opposite end moors a ship, said buoy releasably mounted on said barge, and a mooring line having a majority of its length stored on said barge and a first line end connected to said barge along the axis of said swivel assembly and a second end connected to said buoy, whereby to enable automatic deployment of a connected buoy upon sinking of the barge. .Iaddend. .Iadd.   
     
     
       5.  A method for installing a mooring and fluid transfer system for mooring a ship and transferring fluid between the moored ship and a pipeline beneath the ship, comprising: towing a barge containing a fluid swivel to a desired offshore location;   mounting a buoy on said barge, mounting a flexible line on said barge which is long enough to reach substantially from the seabed to the sea surface at said offshore location, releasing said buoy and line from attachment to said barge, and sinking said barge in a controlled manner under said buoy and deploying said flexible line from said barge;   extending a hawser between said buoy and a ship; and   connecting one end of a hose structure to a rotatable portion of the fluid swivel and the other end to said ship, and establishing a connection between said pipeline and a nonrotatable portion of the fluid swivel. .Iaddend. .Iadd.   
     
     
       6.  A method according to claim 5 additionally comprising recovering said barge from the seabed at a later time by increasing its buoyancy so as to cause it to rise to the surface of the sea. .Iaddend.