Clamp assembly for pipe-laying vessel and method of laying a pipeline

摘要

A pipe-laying vessel including a pipe-laying tower extending upwardly from the vessel, the vessel including a welding station for joining a new pipestring to an end of the pipeline held by the tower, a clamp assembly on the tower for engaging a pipestring with a lower end adjacent to the end of the pipeline held by the tower and with the pipestring extending upwardly from its lower end alongside the tower, wherein the clamp assembly includes a pipestring clamp that serves both the function of a transfer clamp for transferring the pipestring from a position alongside the tower but displaced from the pipe-laying path to a position approximately aligned with the pipe-laying path, and the function of a line-up clamp for lining up the pipestring with the end of the pipeline.