Extend Reel-Ability of HMC New Aegir Reeling Vessel Based on Reliability Based Assessment and Bending Tests Program

Heerema Marine Contractors (HMC) is entering a new era of pipe laying using the reel-lay method for deep and shallow water pipeline installation projects. The new Deep water Construction Vessel (DCV) Aegir is designed to be able to reel/J-lay pipelines for a range of pipe dimension and water depth combinations which on the one side is governed by the equipment limitations (reel drum size, top tension capacity) and on the other side is limited by the code (DNV, API) acceptance criteria for reel/J-lay installation. The paper describes how the code standard acceptance criteria, which have been used to estimate the reel-ability of DCV Aegir and are generally known as conservative approach, can be relaxed in a reliable manner in order to safely extend the DCV Aegir reeling capability. This approach will permit a reduction of minimum reelable pipe wall thickness and result in a wider envelope of water depth applications for reeling from the DCV Aegir. The methodology of relaxation for local buckling and residual ovality criteria has been developed with and approved by DNV specifically for the spooling-on with the DCV Aegir configuration. A series of bend rig tests have been performed at Heriot-Watt University to confirm and validate the new proposed minimum reelable pipe wall thickness. In line with the development of the extended reeling capability, the required tighter specifications for seamless pipe purchased for reeling has been discussed.Copyright © 2012 by ASME