Two ram luffing knuckle boom cranes of the type RL-K 4200-100 LIT will be delivered by Liebherr offshore crane division to Dalian Shipyard (DSIC Offshore) in China for the new high-level semi-submersible BT 4000.
This semi-submersible is a new generation DP3-vessel designed for light work-over and well-intervention operations in water depths up to 2,400m in environmental offshore areas in Brazil, Gulf of Mexico, West Africa and South East Asia.
The cranes will have a maximum lifting capacity of up to 100 tonnes and will mainly be used for pipe-handling and supporting works on-board of the modern semisubmersible. However, the cranes may also be used for lifting goods from supply vessels to the platform – even under rough sea conditions.
With its new foldable boom design, accuracy is a major feature of the RL-K, significantly reducing sway and swing motions of attached loads during all types of lifting operations.
All movements are controlled by an updated version of Liebherr Litronic control system. It allows high-accuracy load manipulation including digital control, storage and follow-up of all lifting data.
The cranes will be equipped with the newly developed pipe- and load-manipulators called ‘gripper yoke’ and ‘riser yoke’. The main feature of this modern load/crane interface is the possibility to rotate the load ±360°and tilt it ±10 degrees. This ensures a soft, high-precision landing, as well as a firm connection of the load with the crane during handling operations.
Currently, the cranes are being constructed at Liebherr's facilities in the harbour city of Rostock, northern Germany. To support this new range of cranes, Liebherr developed an ultra-modern test environment to load and function-test the cranes before delivery in accordance with all relevant offshore regulations. Thisreduces the risk of problems on the customer’s job site.