Vortex induced vibration suppression systems and methods

Abstract

A system comprising a subsea structure beneath a body of water, subject to a water current; an installation vessel floating on the body of water; a line connected to the subsea structure and the installation vessel; and one or more vortex induced vibration suppression devices connected to the line, which have been lowered from the vessel to be installed on the subsea structure.

1 . A system, comprising:
 a subsea structure beneath a body of water, subject to a water current;   an installation vessel floating on the body of water;   a line connected to the subsea structure and the installation vessel; and   one or more vortex induced vibration suppression devices connected to the line, which have been lowered from the vessel to be installed on the subsea structure.   
   
   
       2 . The system of  claim 1 , wherein the subsea structure is selected from an umbilical, a tubular, a riser, and a tendon. 
   
   
       3 . The system of  claim 1 , wherein the vortex induced vibration suppression device comprises a fairing or a helical strake. 
   
   
       4 . The system of  claim 1 , wherein the line comprises at least two lines, the votex induced vibration suppression devices connected to the at least two lines. 
   
   
       5 . The system of  claim 1 , wherein the vortex induced vibration suppression devices are negatively buoyant in water. 
   
   
       6 . The system of  claim 1 , wherein the vortex induced vibration suppression devices comprise one or more shoulders adapted to interface with a collar and/or other vortex induced vibration suppression devices. 
   
   
       7 . The system of  claim 1 , further comprising a spacer between two adjacent vortex induced vibration suppression devices, the spacer connected to the line. 
   
   
       8 . The system of  claim 1 , further comprising a collar exterior to the subsea structure, covering at least a portion of an outside surface of the subsea structure. 
   
   
       9 . The system of  claim 8 , wherein the line is connected to the collar and the installation vessel. 
   
   
       10 . A method, comprising:
 installing a subsea structure in a body of water, wherein the subsea structure is subject to one or more water currents;   connecting at least one line to the subsea structure and to a surface vessel;   lowering at least one vortex induced vibration suppression device from the vessel on the line; and   installing the vortex induced vibration suppression device from the line to the exterior of the subsea structure, covering at least a portion of an outside surface of the subsea structure.   
   
   
       11 . The method of  claim 10 , further comprising:
 installing one or more collars exterior to the subsea structure, the collars adapted to retain the vortex induced vibration suppression devices in an axial location along the subsea structure.   
   
   
       12 . The method of  claim 10 , wherein a collar is installed on the subsea structure before the subsea structure is installed in the body of water. 
   
   
       13 . The method of  claim 10 , wherein the vortex induced vibration suppression device is installed on the subsea structure with a remotely operated vehicle (ROV). 
   
   
       14 . The method of  claim 10 , wherein the vortex induced vibration suppression device comprises an automatic closing mechanism. 
   
   
       15 . The method of  claim 14 , wherein the vortex induced vibration suppression device is installed by moving the device adjacent to the subsea structure to activate the automatic closing mechanism. 
   
   
       16 . The method of  claim 10 , wherein connecting at least one line to the collar and to a surface vessel comprises connecting at least two lines; and lowering at least one vortex induced vibration suppression device from the vessel comprises lowering on the at least two lines.