Patent ID: 6910830

Claim:
A method for laying a pipeline on a sea bed from a lay barge in order to provide controlled thermal expansions, comprising: feeding the pipeline from a pipeline reel, preferably via a stinger, where the pipeline has a radius of initial residual curvature, to a curvature means where a radius of counter curvature is applied on opposite side of the pipeline with respect to the radius of initial residual curvature when the pipeline is running through the curvature means, wherein the curvature means straightens out the pipeline to longer, mainly straight portions having a length with a radius of residual curvature greater than a predetermined smallest radius of residual curvature; and the curvature means exposes shorter portions of length of the pipeline for a radius of counter curvature forming thermal expansion loops having a radius of residual curvature which is less than a predetermined largest radius of residual curvature for the thermal expansion loops; whereby a controlled deflection of the pipe during thermal expansion of the pipeline in operational position on the sea bed and when exposed to operational loads is achieved in that deflection of the pipeline may appear in the thermal expansion loops of the pipeline, wherein all thermal expansion loops are formed toward the same side of the pipeline, whereby bending of the pipeline may occur in same direction in the expansion loops of the pipeline.