Deep water oil and gas exploration make regularly use of Steel Catenary Risers (SCR) to transfer oil and gas from wellheads to host. From the host the oil and/or gas is transferred (after processing) to subsea pipelines by SCRs. Regular practice is to have the SCRs pre-laid on the seabed prior to host installation. Last Summer Heerema Marine Contractors utilized the Heavy Lift Vessel (HLV) Thialf to recover and install 8 pre-laid SCRs. The HLV Thialf also installed the Tension Leg Platform host. The SCRs: two 6, two 8, two 10 SCRs, a 12 Export Gas SCR, a 16 Export Oil SCR were pre-laid in multiple crossings pattern around the TLP. The A&R winch was used to recover the SCRs from approximately 1,350 m waterdepth followed by SCR hand-over to one of the Thialf’s heavy lift cranes for installation to the host. This paper will focus on the SCR recovery and hang-off operation. Several topics will be discussed: the pre-lay, subsea hand-over and the large vessel rotation performed for SCR installation. Additionally, first time use items such as the welded eye connection, open top container for pull-in wire storage and the newly designed hydraulic shackle will also be presented.

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