New lift vessels gain work quickly

Nov. 1, 2003
Cosco Shipping Co. Ltd., continuing its semisubmersible heavy lift fleet expan-sion, added the Kang Sheng Kou to its fleet on Oct. 1.

Cosco Shipping Co. Ltd., continuing its semisubmersible heavy lift fleet expan-sion, added the Kang Sheng Kou to its fleet on Oct. 1. A sister vessel to Tai An Kou, Kang Sheng Kou moved into the market, carrying Transocean's Ron Tappmeyer jackup rig from West Jurong anchorage in Singapore to the west coast of India.

Earlier this year, the Tai An Kou transported Atlantia Offshore Ltd.'s SeaStar TLP hull from Singapore to Corpus Christi, Texas, for Total's Matterhorn field in the Gulf of Mexico. The SeaStar TLP hull, once stowed on the deck of the vessel, had an overhang of 109 ft on both sides, for the largest overhang encountered for these vessels to date. Cosco semisubmersible vessels are managed exclusively by NMA Maritime & Offshore Contractors.

The Tai Ankou carries the SeaStar TLP hull for Total's Matterhorn field in the Gulf of Mexico.
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After completing the Atlantia voyage, the vessel performed a unique skid-out and float-off operation for Anadarko's Marco Polo TLP in June. Due partly to the vessel's fast ballast system and tank arrangements, the skid-out operation took a little over four hours from the MODEC-designed TLP making contact with the vessel to the hull being in the final position.

The load-out was unusual in that there were no link beams, and the TLP hull was cantilevered from the shore side skid beams to the skid beams on the Tai An Kou. Because of the overhang of the cargo when the TLP hull was in the final position, the Tai An Kou had to be carefully heeled away from the quayside to "lift" the cargo off the quayside, so the vessel took all of the weight on her deck.

The Marco Polo TLP hull was discharged using the float-off method. Because the cargo was unusually shaped and on skid beams, the Tai An Kou had to ballast down by the bow to ensure adequate stability throughout the operation.

The Tai An Kou transports two flo-stations for the Shell Awoba project off Nigeria.
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The Tai An Kou performed a skid out and float off operation of Anadarko's Marco Polo TLP hull in June 2003.

Cosco has operated semisubmersible heavy-lift dockships since 1983, and with their two newbuild semisubmersible vessels M/V Tai An Kou and M/V Kang Sheng Kou, have gained experience in the offshore transport market. These sister vessels were designed to be flexible and incorporate the latest industry developments, including high speed of 15 knots, dynamic positioning (DP), favorable motions, and a flexible and fast ballast system. Excellent maneuverability and weather avoidance capabilities provide increased safety to each vessel, NMA says.

Cosco's new vessels are the first semisubmersible heavy-lift vessels to incorporate fully redundant DP-2 systems. This feature was recently used in a successful float-over mating for HHI for Talisman's Bunga Raya topsides, which weighed in at 10,000 tons. The complete float-over installation, including docking, mating, and exit, was completed with the vessels DP capabilities in under six hours, a significant time saving versus previously used methods, NMA says. Noble Denton Europe Ltd. performed engineering for the float-over operation, load-out, and transportation and provided marine and load-out superintendence for the operations.