Abu Dhabi-based National Petroleum Construction Company (NPCC) has awarded Dutch design office Ulstein Sea of Solutions the basic design contract for their new large derrick pipelay vessel ‘DLS-4200’.

The new vessel will be one of the biggest vessels of its kind, combining S-lay double joints pipelay operations with a 3,800-tonne lifting capacity.

The design of the vessel is a modified version of the SOC 3000 design from Ulstein Sea of Solutions (USOS) and will be equipped with an Amclyde Model 80 crane.

‘DLS-4200’ is designed to operate worldwide, but will initially be equipped with a mooring system to operate in the Arabian Gulf and India. However, a future DP2 upgrade is envisaged and catered for in the design to minimise the technical impact in the future.

The vessel features two fixed-pitch, shaft-driven main propellers of 5,500kW each which will allow for a sailing speed of 12 to 13 knots. For the future DP upgrade, five retractable azimuth thrusters of 3,500kW each are required.

The Amclyde main crane is capable of lifting 3,800 tonnes at a 38-metre radius over the stern in tie-back mode and 3,800 tonnes at 28.9 metres without tie-back. In full revolving mode the crane is able to lift 2,680 tonnes with an outreach of 41.1 metres

‘DLS-4200’ has an overall length of 196.9 metres on a moulded beam of 43.4 metres.