Prevention and arresting buckle propagation under high external hydrostatic pressure is a necessity for the deepwater rigid pipelines during installation and operation. The local compromise in geometric integrity will propagate at a high velocity, flattening the pipeline until it encounters a physical barrier that arrests the buckle. Traditionally, external clamp-on type buckle arrestors are considered by the pipeline designers for rigid pipelines that are installed by reeling method. Integral Buckle Arrestors (IBAs) could provide a more reliable method of arresting the propagating buckle during installation and subsequent design life. However, design and installation of integral buckle arrestors for rigid reeled pipeline installation would be a challenge. IBA is fabricated from a thick walled pipe section with the same inner / outer diameter as that of pipeline and wall thickness transition to match the thickness of the pipe towards the ends. For the reeled pipelines, additional cost economies will be achieved by the use of IBAs which allow continuous installation by reel lay vessel without interruptions. This paper gives background information, design and installation considerations and practical issues in the fabrication of IBAs. Recent Subsea7 experiences in design and installation of IBAs will be also addressed in this paper. This paper does not cover the aspects to be taken into consideration, if the buckle arrester is also serving dual purpose as a J-lay support collar.
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