System and method for suction anchor deployment

Abstract

A suction anchor system comprises a substantially tubular suction anchor embeddable in a seabed, a predetermined set of sliding rails, an excavator, and a predetermined set of non-triangular wings disposed about the outer surface of the tubular, and a deployment interface which comprises a deployment cage, a suction anchor lid, and a predetermined set of deployment cage skidding rails disposed about an outer portion of the deployment cage. Using a surface vessel comprising a dispatcher which comprises a storage magazine configured to selectively receive and discharge the suction anchor, a skidding system, and an overhead anchor handler, the suction anchor can be operatively connected and secured to, and placed into fluid communication with, the deployment interface. The deployment interface along its connected suction anchor is lowed from the surface vessel into sea water using the dispatcher until the suction anchor contacts the seabed and allowed to self-penetrate below the seabed due to its own weight.

1 . A suction anchor system, comprising:
 a) a substantially tubular suction anchor embeddable in a seabed, comprising:
 i) a tubular comprising an inner annulus and an outer surface; 
 ii) a predetermined set of sliding rails disposed about the outer surface of the tubular; 
 iii) an excavator disposed at least partially within the tubular; and 
 iv) a predetermined set of non-triangular wings disposed about the outer surface of the tubular; and 
   b) a deployment interface, comprising:
 i) a deployment cage configured to support the weight of the suction anchor; 
 ii) a load bearing connector connected to a top portion of the deployment cage and configured to operatively connect to the flexible connector; 
 iii) a suction anchor lid disposed at least partially within the deployment cage and configured to selectively interface with the tubular; and 
 iv) a predetermined set of deployment cage skidding rails disposed about an outer portion of the deployment cage, the predetermined set of skidding system rails further configured to slidingly accept the predetermined set of deployment cage skidding rails. 
   
     
     
         2 . The suction anchor system of  claim 1 , wherein the predetermined set of non-triangular wings further comprises a predetermined set of padeyes. 
     
     
         3 . The suction anchor system of  claim 1 , wherein the deployment interface further comprises a deployment interface lock disposed about an outer portion of the deployment cage and configured to operatively connect the suction anchor to the deployment interface. 
     
     
         4 . The suction anchor system of  claim 1 , wherein the internal excavator further defines a navigator disposed at least partially within the deployment cage, comprising:
 a) a predetermined set of spray nozzles disposed at least partially within the inner annulus of the tubular;   b) a power supply disposed at least partially within the deployment cage;   c) a pump disposed at least partially within the deployment cage and operatively connected to the power supply;   d) a valve in fluid communication with the pump and disposed at least partially within the deployment cage;   e) a predetermined set of thrusters; and   f) a predetermined set of sensors.   
     
     
         5 . The system for deployment of a suction anchor of  claim 4 , wherein the sensors comprise an inclinometer, a depth sensor, a current sensor, a gyroscope, a multibeam transponder, or a combination thereof. 
     
     
         6 . The suction anchor system of  claim 4 , further comprising a direct power source connection connected to the pump and configured to interface with a power conductor in an umbilical. 
     
     
         7 . The suction anchor system of  claim 4 , wherein the pump is in fluid communication with, and adapted to create negative pressure inside, the inner annulus of the suction anchor. 
     
     
         8 . A system for deployment of a suction anchor system without requiring a remotely operated vehicle (ROV), comprising:
 a) a suction anchor system, comprising:
 i) a substantially tubular suction anchor embeddable in a seabed, comprising:
 (1) a tubular comprising an inner annulus and an outer surface; 
 (2) a predetermined set of sliding rails disposed about the outer surface of the tubular; 
 (3) an excavator disposed at least partially within the tubular; and 
 (4) a predetermined set of non-triangular wings disposed about the outer surface of the tubular; and 
 
 ii) a deployment interface, comprising:
 (1) a deployment cage configured to support the weight of the suction anchor; 
 (2) a load bearing connector connected to a top portion of the deployment cage and configured to operatively connect to the flexible connector; 
 (3) a suction anchor lid disposed at least partially within the deployment cage and configured to selectively interface with the tubular; and 
 (4) a predetermined set of deployment cage skidding rails disposed about an outer portion of the deployment cage, the predetermined set of skidding system rails further configured to slidingly accept the predetermined set of deployment cage skidding rails; and 
 
   b) a surface vessel, comprising:
 i) a vessel deck; and 
 ii) a dispatcher disposed proximate the vessel deck, comprising
 (1) a storage magazine configured to selectively receive and discharge the suction anchor; 
 (2) a skidding system comprising a predetermined set of skidding system rails configured to slidingly accept the predetermined set of sliding rails and the predetermined set of deployment cage skidding rails; and 
 (3) an overhead anchor handler system, comprising: 
 (a) a winch; and 
 (b) a flexible connector operatively in communication with the winch, the flexible connector further operatively, selectively connected to the load bearing connector. 
 
   
     
     
         9 . The system for deployment of a suction anchor of  claim 8 , wherein the predetermined set of skidding rails comprises a predetermined set of modular skidding rails. 
     
     
         10 . The system for deployment of a suction anchor of  claim 8 , where the storage magazine is configured to carry multiple suction anchors. 
     
     
         11 . The system for deployment of a suction anchor of  claim 8 , wherein the deployment interface and suction anchor are configured to be connected to each other on the vessel deck of the surface vessel and deployable as a single unit to seabed 5. 
     
     
         12 . The system for deployment of a suction anchor of  claim 8 , wherein the suction anchor lid comprises a reusable suction anchor lid configured to be reusably connected to a plurality of suction anchors, one at a time, to allow installation of each different suction anchor. 
     
     
         13 . A method of deployment of a suction anchor without using a remotely operated vehicle (ROV), using a system comprising a suction anchor system, comprising a substantially tubular suction anchor embeddable in a seabed, which comprises a tubular comprising an inner annulus and an outer surface, a predetermined set of sliding rails disposed about the outer surface of the tubular, an excavator disposed at least partially within the tubular, and a predetermined set of non-triangular wings disposed about the outer surface of the tubular; a deployment interface which comprises a deployment cage configured to support the weight of the suction anchor, a load bearing connector connected to a top portion of the deployment cage and configured to operatively connect to the flexible connector, a suction anchor lid disposed at least partially within the deployment cage and configured to selectively interface with the tubular, and a predetermined set of deployment cage skidding rails disposed about an outer portion of the deployment cage, the predetermined set of skidding system rails further configured to slidingly accept the predetermined set of deployment cage skidding rails; and a surface vessel comprising a vessel deck and a dispatcher disposed proximate the vessel deck which comprises a storage magazine configured to selectively receive and discharge the suction anchor, a skidding system comprising a predetermined set of skidding system rails configured to slidingly accept the predetermined set of sliding rails and the predetermined set of deployment cage skidding rails, and an overhead anchor handler system which comprises a winch and a flexible connector operatively in communication with the winch, the flexible connector further operatively, selectively connected to the load bearing connector, the method comprising:
 a) operatively connecting and securing the suction anchor to the deployment interface;   b) placing the suction anchor into fluid communication with the deployment interface;   c) connecting the flexible connector to the load bearing connector of the deployment interface;   d) lowering the deployment interface along its connected suction anchor from the surface vessel into sea water using the dispatcher until the suction anchor contacts a seabed; and   e) allowing the suction anchor to self-penetrate below the seabed due to its own weight.   
     
     
         14 . The method of  claim 13 , wherein lowering the deployment interface further comprises:
 a) lowering the suction anchor at an initial height of up to 4 m above the seabed; and   b) further lowering the suction anchor in constant tension mode.   
     
     
         15 . The method of  claim 13 , further comprising, after allowing the suction anchor to self-penetrate below a seabed due to its own weight:
 a) lowering the suction anchor further into the seabed; and   b) maintaining a few tons of constant tension to ensure the suction anchor is vertical.   
     
     
         16 . The method of  claim 15 , further comprising, after allowing the suction anchor to self-penetrate below the seabed due to its own weight:
 a) switching on the pump to create negative pressure inside the suction anchor; and   b) using the pump to pump out water and soil or water-soil mixture in order to fix the suction anchor deeper into the seabed.   
     
     
         17 . The method of  claim 16 , wherein the suction anchor lid further comprises multiple spray nozzles placed inside the suction anchor lid, the spray nozzles capable of rotating inside the suction anchor lid, the method further comprising using the multiple spray nozzles to aid deployment of the suction anchor into the seabed by using the spray nozzles perform jetting operation which clears the path using jets of high pressure to create a guided bore for embedding suction anchor. 
     
     
         18 . The method of  claim 16 , further comprising:
 a) unlocking the locking mechanism to detach the deployment interface from the suction anchor system, thereby removing the fluidic connection between the suction anchor lid and the suction anchor head; and   b) recovering the deployment interface to the deck of the surface vessel.   
     
     
         19 . The method of  claim 18 , further comprising:
 a) moving a next suction anchor along the skids to a predetermined position; and   b) connecting the next suction anchor to the deployment interface for deployment of the next suction anchor.   
     
     
         20 . The method of  claim 16 , further comprising:
 a) dredging to remove soil above the suction anchor to connect the deployment interface to the head of the suction anchor;   b) reconnecting the deployment interface to the suction anchor; and   c) once connected, pumping to remove the suction anchor from the seabed.