Crane-Less, Diver-Less Platform Decommissioning Vessel to Reduce Cost and Enhance Safety and Efficiency

Abstract

Conventional methods of offshore platform and infrastructure removal have relied heavily on floating cranes and diver intervention. This has led to high cost, significant number of support vessels in the vicinity of the operation and risks associated with manned diving. This paper will attempt to show an alternative vision based on innovative technology to: Enhance safety by using ROVs instead of manned diving and also to reduce the number of vessels employed in any given scenario thus reducing risks associated with SIMOPS. Improve the operational window. Crane vessels normally require good weather, low wave height and swell and low wind speed. The presented alternative has far less weather demands. Reduce time (and thus cost) on site due to the capability of the proposed design. Enhance efficiency as design is suitable for all offshore infrastructure removal including complete topsides, complete jacket or reduced number of jacket lifts, subsea pipeline, pipe and flexibles, mattresses and other subsea infrastructure within vessel lift capability.