As turbines get heavier and blades longer, the demands for offshore foundations are clear: they need to be stiffer, stronger, and reliable. For the production process, it means integrating new technology and more efficient manufacturing systems.
Everything starts with an efficient manufacturing process
Today’s offshore towers are massive. The height of a typical tower is from 70 to 120 meters, the turbines can be up to 10 MW, and the blades are over 100 meters long. In order for the tower to successfully harness the powerful offshore winds, the foundation needs to be stiff and strong.
When compared to onshore foundation manufacturing, the cost to manufacture offshore foundation is considerably high. Due to this, it is extremely important to optimize every part of the foundation production flow to maintain competitiveness and cost-efficiency.
PEMA offshore foundation manufacturing lines are always engineered for the manufactured foundation type, ensuring the highest reasonable automation level.
Pemamek designs and manufactures specially developed machines for monopile and transition piece production. The line integrates all crucial production phases.
Welding automation for monopiles
Monopile is the most common foundation type for
offshore wind turbines used today. Typically driven into
the seabed, the monopile supports the wind turbine
tower through a transition piece. Production of these
most heaviest structures of industry needs high
performance welding and bevelling with the highest
quality of rotators and other manipulation machines.
The modern production technology enables the integration of various production phases, such as plate joining, bevelling, flange fitting and rotating and transporting monopile sections. The possibility of integration enables significant quality improvement, even for thick material structures.
All the process steps have the one and the only target – to efficiently join a complete monopile while minimizing defects. It is Pemamek’s core knowhow to excel each process step, regardless of whether it is to weld plate joints, longitudinal seams of shells, or circular weld in full monopile assembly.
In order to guarantee maximized production performance, it is crucial to estimate the takt time of each process step. Additionally, the possible bottlenecks need to be analyzed, but also to how much each process step really boosts the total production efficiency.
Pemamek designs and manufactures specially developed machines for monopile and transition piece production. The line integrates all crucial production phases.
Welding of jacket nodes is one of the most demanding work phases due to the variable geometry grooves. With robotic welding, the process can be automated which improves productivity significantly.
Offshore jacket foundations ready to be installed. The jacket structure has a lot more complex structures than the monopile foundation.
Robotized jacket welding
A jacket structure has a much more complex geometry than a monopile foundation. Essentially, a jacket consists of three or four legs diagonally and horizontally braced against a transition piece in the center. The legs are also interconnected with bracing to provide the required stiffness.
Nodes of jacket legs and bracings include the most demanding welding joint of the whole structure. Welding of this variable geometry groove can be robotized and a remarkable efficiency leap achieved. With an adaptive robot welding, such as PEMA WeldControl 300 SCAN, manufacturers can efficiently implement multi-pass welding. The workpiece is scanned and data analyzed in the software’s built-in system, which scans the real geometry and corrects the robot welding paths accordingly.
Successful utilization of these technologies in automated welding means that entire multi-pass welding can be pre-defined into the controller where the operator selects the correct program. After that system can handle welding parameters as well as wire positioning through the entire multi-hour weld. The operator is only supervising that the result is satisfying. This allows even one operator to supervise multiple welding heads working at the same time.
Quality and higher output
As wind energy is increasingly moving out to the sea and more players are coming to the markets, the focus needs to be shifted now on the manufacturing processes and how those can be developed more efficient, and reliable.
When working with huge offshore wind structures efficiency is one of the factors, but it also means savings in floor space utilization, more working safety, and a cleaner working environment. To summarize, successful automation means quality, higher output, and better working conditions.
