News
Published in: Wind, Press Releases
- Launch customer repair project at 50MW wind park in South Asia
- Client technicians trained in the Netherlands and Denmark
- “Re-FIT” method: cost-effective alternative to blade replacement
- Reduced downtime; no offsite blade transport
- Upcoming projects in India, Brazil and US
Almelo, Netherlands/Vejle, Denmark 1 July 2025 — Dutch rotor blade expert We4Ce and Danish precision machining specialist CNC Onsite have completed their first joint project to transfer blade repair expertise to a wind park in South Asia. In May, the companies trained the customer’s technicians to independently repair loose blade root bushings on 26 turbines—marking the first in-field use of their new remanufacturing method. The approach offers a cost-effective, sustainable alternative to full blade replacement by eliminating the need for offsite transport and reducing blade waste.
CNC Onsite’s custom-built precision machine removed the damaged bushings on-site, enabling the park’s technicians to apply We4Ce’s patented “Re-FIT” bushing and fastening method. Ahead of the 50MW project, the technicians were trained at We4Ce’s laboratory in the Netherlands on the repair technology, and at CNC Onsite in Denmark on operating the precision machine. Delivered under a licensing model, this technology transfer enables wind parks to carry out major blade repairs using their own service teams.
Following their training, the South Asian service team set up a field workshop at the wind park and, under the supervision of CNC Onsite and We4Ce, carried out large-scale repairs over several weeks. “Securing and completing this first contract for our bushing and insertion method is the result of fine engineering for practical application,” says Arnold Timmer, managing director of We4Ce. “We first conceived the idea in early 2022 after an initial job with a client in India, and then spent three years developing and testing the solution.”
By adopting the remanufacturing technology, the customer will restore more than 1,000 bushings. The process combines precision milling, a specialized fixing method, and the installation of replacement bushings to produce a like-new component engineered for reliable performance over a lifespan of up to 20 years. This approach represents a significant improvement over conventional repair methods.
Remanufacturing technology: A future option for O&M
With operation and maintenance (O&M) crucial to long-term turbine performance, remanufacturing — restoring parts to equal of higher quality than original condition — is likely to shape how the wind sector approaches maintenance in the years ahead.
Replacing bushings as an aftersales activity is a complex process, requiring precise removal and re-insertion for a strong mechanical bond.
Three industrial work tents, each measuring 100 m² and housing a rotor blade, were set up as clean environments. In the first tent, one blade was drilled; in the second, the bushing replacement was carried out; and in the third, final flattening was completed.
The We4Ce and CNC Onsite method provides significant advantages: up to 60 percent in cost savings, reduced downtime, and environmental benefits from eliminating potential blade waste and blade transportation, which would typically incur high logistical costs and CO2 emissions.
Efficient drilling in fiberglass blades
CNC Onsite designed and built a custom machine to drill out defective bushings from the rotor blades’ composite laminate, creating accurately dimensioned holes for replacements.
“Drilling in fiberglass is typically hard on the tools causing them to wear out quickly. That is why as part of this project, we developed special drills to achieve high precision and efficiency,” explains Soren Kellenberger, partner and sales director, CNC Onsite.
Infusion technology ensures long-lasting bushing bond
We4Ce applied its patented infusion technology to fasten the new replacement bushing in place, ensuring exact centering. Epoxy resin was infused through an inlet tube into the base of the bushing, with vacuum processing ensuring even distribution around the cavity.
The blade root bushing, or insert, is a safety-critical component that connects the rotor blade to the turbine hub. In some blades, polyester is used to embed the bushing. If during the original manufacturing process this material shrinks or is unevenly distributed, microcracks can arise with cracks developing over time. Such cracks reduce the bonding surface and increase the risk of the bushing loosening—potentially leading to blade failure.
We4Ce and CNC Onsite are currently preparing for upcoming projects with significant potential, including Brazil and the US.
About We4Ce
Headquartered Almelo, the Netherlands, We4Ce has more than 25 years’ experience in supplying technology for rotor blades upfront manufacturing and for after sales. It starts with rotor blade design, blade root bushing technology M20-M42, and technology for sectional exchangeable rotor blade tips. For the aftersales sector, We4Ce performs Root Cause Analyses (RCA) of blade failures and provides a licensing model for the Re-FIT blade root bushing re-manufacturing method. Working closely with wind park owners, We4Ce’s research lab performs a range of fatigue tests and extreme load tests for different sizes and parameter changes, aiding the development of bushings for manufacturers. We4Ce also works with TNO test institute for large size sample testing and approval for the certification bodies, including TüV and UL.
www.we4ce.eu
About CNC Onsite
Headquartered in Vejle in Denmark, CNC Onsite designs and delivers high precision mobile machining equipment for wind turbines including offshore foundations. Machines built by CNC Onsite are designed to be flexible using its proprietary “building blocks” approach, which means machinery can be built to match a range of tasks. CNC Onsite serves the onshore and offshore wind energy sector delivering as standard solutions: machining of large diameter steel flanges and blade root ends; specialized repair services covering yaw ring, inserts in blade root, rotor lock, generator shaft, bearing housing and threaded holes. Removal and replacement of worn and broken bolts round off the offering.
www.cnconsite.dk
Media contact
Dr. Malene Conlong
M.conlong@mollerint.dk
+49151 53930015
