Maritime cranes for the wind industry
Liebherr also offers the right solution for the wide range of requirements of the wind power industry in the maritime sector. Cranes and material handling equipment are employed both at harbors and at sea, on crane ships and on floating installation platforms.
The wide range of mobile harbor cranes and ship cranes from Liebherr ideally matches the many different requirements when loading wind power components in harbors. The cranes are used to load and unload ships, low-loaders and goods wagons. This involves heavy cargo such as generators with a lifting capacity of over 70 tonnes or rotor blades with a span of more than 40m. Safety and precision are important factors. In addition to the design of the cranes, the electronic control systems are of utmost importance. These control systems one of the core competencies of Liebherr and are therefore also developed in-house..
Liebherr also offers convincing solutions for constructing wind turbines at sea. The offshore heavy duty cranes feature lifting capacities of up to 3,000 t.
Loading of wind power components at the harbor
Safety and precision are the most important criteria when it comes to transferring heavy loads in the wind power sector. The strengths of the Liebherr mobile harbor cranes are brought to bear here. Independently powered, closed hydraulic circuits employ a minimum of components and combine extremely short reaction times and maximum precision with operating reliability and safety.
The mobile harbor cranes reach maximum lifting capacities of up to 208t. In tandem operation, the patented multi-crane control system SYCRATRONIC® enables lifting capacities of up to 416t. The dynamic anti-collision control system in conjunction with Vertical Line Finder also ensures that work is carried out safely and precisely.
Heavy-duty ship cranes for transportation and loading
Liebherr supplies the CBB series, a separate line of heavy-duty ship cranes, to load and transport wind turbines. These cranes can also be equipped with the dynamic anti-collision control system for enhanced safety in crane operation. The cranes can lift loads of up to 450t.
Erection of offshore wind turbines
Liebherr's offshore heavy duty cranes feature lifting capacities of up to 3,000t and are used to erect wind turbines at sea. All requirements can be catered for: diesel-powered or electric drive units, explosion-protected cranes and cranes for ambient temperatures between +40°C and -50°C, and special lowering depths down to 3,000m below sea level.
Crane control system
Synchronous control for automated tandem lifts
In standard mode, each crane has to be operated by one driver for tandem lifts. The drivers are informed about the main functions of both cranes (e.g. speeds, etc.) on their respective monitors. This enables both crane drivers to control the two cranes independently, but yet coordinated.
A far more efficient variant is the "Automatic Parallel" mode with one person controlling both cranes. In this mode, the traverse remains parallel to the ship or to the initial position, and an automatic control system computes the movements of the jib heads of both cranes. Since the length and hook height difference are kept constant during movement, any unwanted diagonal pull in the cables can be ruled out.
A third option for tandem lifts is the "Automatic Rotation" mode in which the traverse can rotate. The crane driver only has to control the direction or rotation of the traverse, while the control system computes the necessary movement of the jib heads of both cranes.
Dynamic anti-collision control
The dynamic anti-collision control system manages simultaneous movements of two or more cranes. Every crane is fully protected while its performance remains constantly high.
When several cranes work simultaneously, the movements of the individual crane can be controlled based on the current position of the other cranes. The special feature of the dynamic anti-collision system from Liebherr is that it automatically computes the actual position, speed and acceleration of each crane, as well as their load torque limitation. This allows the crane driver to work absolutely safely with maximum flexibility.
Vertical line finder prevents load vibrations
The vertical line finder is an optional control aid for avoiding diagonal pull on the load. This may occur when the distance between the crane driver and the load is too long or when the center of gravity is not symmetrical.
The control system controls the position of the boom by showing the exact vertical rope position before the load is lifted. Since the load does not vibrate, the danger of damage to the load or the crane is minimized. The system also provides greater safety for the crane driver and his environment.