Methods of laying subsea pipelines

A subsea pipeline system comprising:

• a pipe laying vessel, a subsea pipeline, and a spooling structure assembly, wherein the subsea pipeline is wrapped around the spooling structure assembly, wherein the spooling structure assembly comprises a pile, a spool surrounding the pile, the spool having a taper such that a top outside diameter at a top surface of the spool is larger than a bottom outside diameter at a bottom surface of the spool, and a pipe support attached to the spool, wherein the pipe support is moveable with respect to the spool, and wherein the spooling structure assembly is adapted to be placed on the seafloor.

A method of laying subsea pipeline on a seafloor comprising:

• providing a pipe laying vessel, placing at least two spooling structure assemblies on the seafloor, and laying the subsea pipeline in a continuous loop around the at least two spooling structure assemblies, wherein the at least two spooling structure assemblies each comprise a pile, a spool surrounding the pile, and a pipe support attached to the spool, wherein the spool has a taper such that a top outside diameter at a top surface of the spool is larger than a bottom outside diameter at a bottom surface of the spool.

A method of laying subsea pipeline on a seafloor comprising:

• providing a pipe laying vessel, placing at least two spooling structure assemblies on the seafloor, and laying the subsea pipeline in a continuous loop around the at least two spooling structure assemblies, wherein the at least two spooling structure assemblies each comprise a pile, a spool surrounding the pile, and a pipe support attached to the spool, wherein the pipe support is moveable with respect to the spool.