Offshore vessel for laying a pipeline on the seabed, and a method for handling pipe sections

An offshore pipelaying vessel for laying a pipeline on a seabed, comprising a pipeline-laying installation having:

• a preassembly line with a joining station to form multi length pipe sections by joining single length pipe sections end to end;
• an inspection station associated with said preassembly line for inspecting joints made by the joining station of the preassembly line;
• an assembly line with a pipeline assembly station to assemble a pipeline to be launched from the vessel by joining multi and/or single length pipe sections end to end;
• and
• a conveyor system for transporting multi and single length pipe sections, said conveyor system comprising an entry-and-exit location,
• wherein the conveyor system is configured to allow transportation of multi and/or single length pipe sections at least along the following routes:
• directly from the entry-and-exit location to the assembly line;
• indirectly from the entry-and-exit location to the assembly line via the preassembly line and said inspection station;
• and
• from the entry-and-exit location to the preassembly line and said inspection station, and after passing said inspection station directly to the entry-and-exit location.

A method to handle pipe sections on an offshore pipelaying vessel having a preassembly line and an assembly line, wherein the preassembly line is not aligned with the assembly line, and wherein the method comprises the following steps:

• transporting single length pipe sections from an entry-and-exit location to the preassembly line;
• joining single length pipe sections end to end in the preassembly line to form a multi length pipe section;
• transporting the multi length pipe section to an inspection station associated with the preassembly line;
• and
• inspecting the joints of the multi length pipe section in said inspection station,
• wherein in case the joints are approved by said inspection station, the multi length pipe section is transported to the assembly line to form the pipeline to be launched from the vessel,
• and wherein in case the joints are rejected by said inspection station, the multi length pipe section is transported directly to the entry-and-exit location.