2. Wind Composite Services Group Blade Repair Service Guidance
01/06/2019
Wind Composite Services Group
Blade Repair Service Guidance
20 May, 2015

3. Wind Composite Services
Owned by Tecsis, 2nd largest wind blade producer globally.
Servicing blades since 2007.
Data base of ___________inspected and repaired blades.
Three types of work platforms available for up tower repairs.
Engineers on hand to backup service teams.
QC of every repair before departure from site.

4. Safety First

5. Approach to Blade Repairs

6. Non-Structural Repairs
Non-Structural damage does not affect the blade’s sparcap or bonds.
Sparcap

7. Non-Structural Repairs

8. Leading Edge Erosion

9. Further Neglect Can Result in Worse Damage

10. Lightning Damage
Neglecting lightning damage can lead to serious problems
Lightning Protection System (LPS) may be compromised.

11. Lightning Damage

12. Questions for the ISP
Do you have written work instructions for this repair?
Are the materials either the same or similar to the OEM’s?
What resin system are you using? Epoxy or Polyester? Is it compatible?
What is the fairing compound? Bondo, epoxy or Polyurethane?
What paint are you using?
While up-tower can you check the LPS? Drain hole?

13. Structural Damage Can the blade be repaired successfully?
If so can it be done up tower, downtower
or shipped to a factory?
Is the repair worth the money?
Worth the risk?
Are there other alternatives?
Do you or your ISP have the knowledge to
make a good decision?

14. A Few Examples of Structural Damage
Interior cracks
Core debonded

15. Decision to repair up tower
may be easy in some cases.
But again ask questions

16. Questions to Ask Yourself
Do we know the Root Cause of the damage?
Did we address the root cause to prevent further damage after repairs?
Do we have enough information to make a good decision as whether to repair or replace?
Did we do a risk analysis?

17. Challenge the ISP Do they have written work Instructions?
If so, on what are they based?
Does the ISP have an in house composite engineer? Analytical tools?
Do they have experience in this repair?
Price cap?
Warranty?
Is the access method appropriate for the repairs?

18. Root Cause Analysis Identify key contributors to the blade damage
Underestimated design loads
Malfunctioning of control and safety systems
Abnormal environmental conditions
Manufacturing defects
Design related issues

19. Structural Analysis and Validation
Perform structural analysis based on operating conditions.
Simulate and validate structural response to field test data.

20. Do we have photos such as these? Or the capabilities?

21. Engineered Repairs
Based on results obtained, a detailed repair solution is prescribed.
Optimized laminate schedule is determined based on structural analysis
Repairs are validated during repairs
Documentation of the work is retained

22. Summary Know what questions to ask
Make decisions based on facts, data and financial sense
Don’t be afraid to go to outside help
Engineered solutions lead to longer asset life
Lead to overall savings in O&M costs