METHOD AND APPARATUS FOR INSTALLATION OF A FLOW LINE RISER ON AN OFFSHORE STRUCTURE

摘要

A flow line riser is installed on an offshore structure by laying a pipeline to a point on water bottom adjacent the structure and raising the offshore structure to water surface where lengths of pipe are attached perpendicularly to the pipeline to form a riser, the pipeline and riser being lowered to water bottom as the lengths of pipe are attached while longitudinally maintaining substantially constant tension on said pipeline. When the pipeline and connected riser reaches water bottom, it is then attached to the structure.