公开(公告)号：US20230358336A1

公开(公告)日：2023-11-09

申请号：US17802119

申请日：2021-02-24

Applicant: Subsea 7 Norway AS

Inventor： Christian Linde OLSEN ,  Fartein Thorkildsen

IPC: F16L1/18 ,  F16L1/20 ,  F16L57/02

CPC classification number: F16L1/18 ,  F16L1/206 ,  F16L57/02

Abstract: A subsea pipeline (14) has a friction-reducing outer coating, treatment or finish (30) that extends along discrete regions mutually spaced along the length of the pipeline. During laying, curvature is imparted to the pipeline (14) along its length, for example by the residual curvature method or by snake-lay, to create expansion loops (26) of increased curvature relative to intermediate portions (28) of the pipeline (14) that join those loops (26). Each of the loops (26) is coincident with a respective one of the regions that bear the friction-reducing outer coating, treatment or finish (30). This facilitates lateral movement of the loops (26) relative to the seabed (16) to mitigate and control buckling in use of the pipeline (14).