Offshore staff
ABU DHABI -- National Petroleum Construction Co. (NPCC) has contracted the Chinese shipyard Zhenhua Heavy Industries to build the DLS 4200 derrick laybarge.
The vessel concept, developed by Ulstein Sea of Solutions (USOS) based in Vlaardingen, the Netherlands, combines double joint S-lay capabilities with a 4,200-ton (3,810-metric ton)lifting capacity.
The DLS 4200 is to be equipped with a 10-point mooring system to operate in the Arabian Gulf and India, although the vessel is designed to work worldwide.
The 197-m (646-ft) long vessel features a center double joint firing line to optimize pipelay operations. This and the double joint fabrication areas are on the freeboard deck, covered by the main deck. According to USOS, this provides a clean, dry environment for the pipelay equipment, and an unobstructed main deck for lifting operations.
The Amclyde Model 80 main crane can handle lifts of up to 4,200 tons at a 125-ft (38-m) radius over the stern in tieback mode, and 4,200 tons at 95 ft without tieback. In full revolving mode the crane can lift 3,635 tons (3,300 metric tons) with an outreach of 130 ft (39 m).
Two fixed-pitch, shaft-driven main propellers (5,500 kW each) provide a transit cruising speed of 13 knots. In order to upgrade the vessel to DP-2 (allowed for in the design), five retractable azimuth thrusters of 3,500 kW each will be needed.
06/14/2010
