Subsea foundation

Abstract

A subsea foundation system and a method of connecting a lower pipe portion to a subsea foundation are provided. The method includes: providing the subsea foundation, an upper pipe portion being connected to the subsea foundation, deploying the subsea foundation subsea; and connecting the lower pipe portion to the upper pipe portion. The subsea foundation system includes: the subsea foundation; the upper pipe portion connected to the subsea foundation, and the lower pipe portion. The lower pipe portion can be connected to the upper pipe portion subsea. The lower pipe portion may be connected to the subsea foundation in a stowed position before deployment subsea. The lower pipe portion may be connected to a pull-in arrangement before deployment subsea.

1 . A method of connecting a lower pipe portion to a subsea foundation, the method comprising:
 providing the subsea foundation comprising an upper pipe portion connected to the subsea foundation;   providing a lower pipe portion and a pipe overlap section; and   connecting the lower pipe portion to the upper pipe portion such that the pipe overlap section overlaps a portion of the upper pipe portion and/or the lower pipe portion.   
     
     
         2 . The method according to  claim 1 , wherein the upper pipe portion does not protrude beyond the bottom of the subsea foundation and wherein, when the lower pipe portion is connected to the upper pipe portion, at least part of the lower pipe portion protrudes beyond the bottom of the subsea foundation. 
     
     
         3 . The method according to  claim 1 , wherein the method comprises:
 connecting the lower pipe portion to the subsea foundation in a stowed position;   deploying the subsea foundation subsea with the lower pipe portion in the stowed position; and   releasing the lower pipe portion from the stowed position subsea.   
     
     
         4 . The method according to  claim 1 , wherein the method comprises:
 connecting the lower pipe portion to a pull-in arrangement and then deploying the subsea foundation subsea with the lower pipe portion connected to the pull-in arrangement,   wherein connecting the lower pipe portion to the upper pipe portion comprises using the pull-in arrangement to connect the lower pipe portion to the upper pipe portion.   
     
     
         5 . The method according to  claim 4 , wherein the pull-in arrangement is connected to the lower pipe portion via the pipe overlap section. 
     
     
         6 . The method according to  claim 1 , wherein the pipe overlap section is fixed to the lower pipe portion and overlaps a portion of the upper pipe portion when the lower pipe portion is connected to the upper pipe portion. 
     
     
         7 . The method according to  claim 1 , wherein the subsea foundation comprises a suction anchor. 
     
     
         8 . The method according to  claim 1 , wherein the inner diameter of the lower pipe portion is the same as the inner diameter of the upper pipe portion and the outer diameter of the lower pipe portion is the same as the outer diameter of the upper pipe portion. 
     
     
         9 . The method according to  claim 1 , wherein the subsea foundation comprises a pipe connection guide for guiding the connection between the upper pipe portion and lower pipe portion, wherein the pipe connection guide is fixed via the pipe overlap section to the upper pipe portion or the lower pipe portion. 
     
     
         10 . A subsea foundation system, wherein the subsea foundation system comprises:
 a subsea foundation;   an upper pipe portion connected to the subsea foundation;   a lower pipe portion; and   a pipe overlap section, wherein the pipe overlap section is arranged to overlap a portion of the upper pipe portion and/or the lower pipe portion when the lower pipe portion is connected to the upper pipe portion.   
     
     
         11 . The subsea foundation system according to  claim 10 , wherein the upper pipe portion does not protrude beyond the bottom of the subsea foundation and wherein, when the lower pipe portion is connected to the upper pipe portion, at least part of the lower pipe portion protrudes beyond the bottom of the subsea foundation. 
     
     
         12 . The subsea foundation system according to  claim 10 , wherein the subsea foundation is for deployment subsea, wherein a lower pipe portion connected to the subsea foundation in a stowed position, and wherein the subsea foundation system is arranged such that subsea the lower pipe portion can be released from the stowed position. 
     
     
         13 . The subsea foundation system according to  claim 10 , wherein the lower pipe portion is connected to a pull-in arrangement, and wherein the subsea foundation system is arranged such that subsea the lower pipe portion can be connected to the upper pipe portion using the pull-in arrangement. 
     
     
         14 . The subsea foundation system according to  claim 13 , wherein the pull-in arrangement is connected to the lower pipe portion via the pipe overlap section. 
     
     
         15 . The subsea foundation system according to  claim 10 , wherein the pipe overlap section is fixed to the lower pipe portion and overlaps a portion of the upper pipe portion when the lower pipe portion is connected to the upper pipe portion. 
     
     
         16 . The subsea foundation system according to  claim 10 , wherein the subsea foundation comprises a suction anchor. 
     
     
         17 . The subsea foundation system according to  claim 10 , wherein the inner diameter of the lower pipe portion is the same as the inner diameter of the upper pipe portion and the outer diameter of the lower pipe portion is the same as the outer diameter of the upper pipe portion. 
     
     
         18 . The subsea foundation system according to  claim 10 , wherein the system comprises a pipe connection guide for guiding the connection between the upper pipe portion and lower pipe portion, wherein the pipe connection guide is fixed via the pipe overlap section to the upper pipe portion or the lower pipe portion.