About this project:
Client:
EDF Renewables
Windfarm:
Long Park
Address:
Galashiels, Scotland
Date:
September 2024
Duration:
84 hours
Access Method:
Rope Access
Project Information
Bladestar Renewables Ltd were tasked with repairing a Cat 5 repair to a blade in the Galashiels, Scotland. Following on from a routine internal inspection, x2 chord ways cracks were found on the pressure side shell. Utilising our own inhouse Limited Authorised technicians we were able to work self-sufficiently. This enabled us to handle the repair from start to finish without any external support from the customer. The external shell also had a crack which was visible from the ground. Due to climatic conditions it was decided the team would tackle the internal repair first in order to keep delays to a minimum.
Key Points
• Repair time = 84 hours via rope access.
• Bladestar inhouse Senvion Limited AT’s.
• All internal layers, core and external layers affected incl. SPAR.
• Common issue found across LM blades.
• Detailed repair report sent out to customer within 72 hours of completion.
• Bladestar inhouse Senvion Limited AT’s.
• All internal layers, core and external layers affected incl. SPAR.
• Common issue found across LM blades.
• Detailed repair report sent out to customer within 72 hours of completion.
Investigation
N/A
Repair
Internal Repair:
The internal repair was started first to minimise weather downtime externally. The two chord ways cracks measure at 800mm and 300mm and located 10m from the root of the blade. Due to knowing that all laminate layers were affected, the team set to work in removing the defective internal laminate and core. Once the core was removed, the external laminate defect was also visible. Once all defective core was removed, it was found that the defect had travelled into the SPAR. New core was bonded into position, profiled, and surrounding laminate chamfered in preparation for the covering laminate. SPAR was then chamfered and Uni-Directional laminate completed to conclude repair of the SPAR. Internal covering biaxial laminations were then applied along with a reinforcement laminate. The blade was then thoroughly cleaned and decanted in order to move to the external repair. • x1 large core replacement completed. • x11 layers Uni-Directional (SPAR) repaired. • Internal Biaxial laminations completed across an area of approx. 1.5m2.
External Repair:
The 800mm internal crack mirrored the external crack exactly. Team began removing topcoat and defective laminate in order to expose the previously completed core replacement. External Uni-directional layers also required repair. The SPAR was chamfered and x13 layers of UD laminated. Covering Biaxial laminations were applied, profiled, filled, sanded and painted to complete.
The internal repair was started first to minimise weather downtime externally. The two chord ways cracks measure at 800mm and 300mm and located 10m from the root of the blade. Due to knowing that all laminate layers were affected, the team set to work in removing the defective internal laminate and core. Once the core was removed, the external laminate defect was also visible. Once all defective core was removed, it was found that the defect had travelled into the SPAR. New core was bonded into position, profiled, and surrounding laminate chamfered in preparation for the covering laminate. SPAR was then chamfered and Uni-Directional laminate completed to conclude repair of the SPAR. Internal covering biaxial laminations were then applied along with a reinforcement laminate. The blade was then thoroughly cleaned and decanted in order to move to the external repair. • x1 large core replacement completed. • x11 layers Uni-Directional (SPAR) repaired. • Internal Biaxial laminations completed across an area of approx. 1.5m2.
External Repair:
The 800mm internal crack mirrored the external crack exactly. Team began removing topcoat and defective laminate in order to expose the previously completed core replacement. External Uni-directional layers also required repair. The SPAR was chamfered and x13 layers of UD laminated. Covering Biaxial laminations were applied, profiled, filled, sanded and painted to complete.
What the client had to say...
EDF has a wide and varied fleet of wind turbines which generates One Gigawatt of renewable energy. This sizeable fleet requires constant maintenance from specialist personnel and contractors in order to maintain the highest possible efficiency, one of those contractors is Bladestar Blade Repair.
EDF chose to work with Bladestar due to their expertise in blade internal and external inspections, structural repairs and Root Cause Assessment of faults.
Throughout the time EDF have worked with Bladestar they have found them to be highly skilled, approachable and professional. Their work ethic is second-to-none and they are willing to go above and beyond in order to achieve our goal.
Both Chris and Joe are stand out in their abilities and they have contributed to EDF’s values and mission towards net zero.
I can highly recommend Bladestar for any blade repair work or inspections and EDF will be collaborating with them going forward.
Mark Haggerston
Blade Engineer