COSL Takes Delivery of Newbuild Seimsub COSLProspector from CIMC Raffles

Yantai CIMC Raffles Offshore Limited announced Wednesday that COSLPropsector (mid-water semisub), the fourth deepwater semisubmersible drilling rig built by CIMC Raffles for China Oilfield Services Limited (COSL), has been delivered in Yantai, Shandong, China. Adopting the most advanced design concept and being satisfied with the global strictest standards, it can work in the harsh Norwegian North Sea.

The COSLProspector is a DP3 vessel with length of 343 feet (104.5 meters), width of 231 feet (70.5 meters), height of 123 feet (37.55 meters), and an operating depth of 4,921 feet (1,500 meters), a drilling depth of 24,934 feet (7,600 meters) and a designed operating temperature of minus 20 degrees Celsius. A maximum variable deck load of 5,000 tons, the multifunction platform is also able to accommodate 130 personnel. It is classed by DNV and CCS, and satisfied with the strictest standards of PSA and NORSOK. Equipped with 10,000 controllers and alerts, the remote monitoring can be achieved in this high-automatic unit.

On the base of GM-4000 series, COSLProspector is jointly designed by AG (Agility Group), COSL and CIMC Raffles. Furthermore, CIMC Raffles is responsible for all detailed design, construction and commissioning work. It adopts the most advanced power management and environmentally-friendly design concept, and facilities with DP3 close bus-tie, variable frequency drive, escape chute system and auto ice-cleaning technology. Compared with last delivered COSL series semisubmersible drilling rigs [COSLPioneer (mid-water semisub), COSLPromoter (mid-water semisub) and COSLInnovator (mid-water semisub)], COSLProspector adds ICE-T, CLEAN and WINTERIZATION, to satisfy ice-class, environmentally-friendly and low-temperature requirements. COSLProspector is made up by 112 blocks, over 700 mechanical equipment, more than 2.624,671 foot (800,000 meter) cable and 35,000 pipes. There are 46,500 test points of MCR, which is increased by 45 percent compared with three semi drilling rigs of the same series delivered already. One hundred and eighteen significant technical improvements have been made. In addition, weight deviation between inclined test and theoretical calculation is 80 tons and the noise level is controlled less than 45 dB in the living area. The alignment tolerance of global mating of upper and lower hull is limited to within .39 inches (10 millimeters), and finally, the percent of pass of NDT is as high as 98 percent.

Yu Ya, president of CIMC Raffles, said, “The construction period of COSLProspector is the shortest one since 2009, taking only 35 months from design to delivery. Compared with similar semisubmersible drilling rig built by the Korean shipyard, it saves 10 months in construction. It is regarded as the “Quality Project”, which means ‘high position, high standard, high quality and high efficiency’, built by CIMC Raffles and COSL.”

Li Yong, CEO of COSL, said that the delivery of COSL improves our capabilities in deepwater operating and international market competence and completes COSL deepwater drilling facility building. We are confident to manage and operate COSLProspector efficiently.

COSLProspector is the 7th deepwater semisubmersible drilling rig built by CIMC Raffles. CIMC Raffles has always been supporting COSL in facilities towards deepwater exploration. With four semisubmersible drilling rigs built for COSL, three of which are six-times rewarded as “Rig of the Month” by Statoil due to their outstanding performance. The successful delivery of COSLProspector is a milestone for Chinese deepwater drilling rig going into the global mainstream market, for the new connotation of the 21st century Maritime Silk Road.


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