TURBINE BLADES

BLADE ROOT REPAIRS

Reduce costs and downtime with our blade root repair.

Using precision machining, the damaged bushings at the blade root are repaired at the wind park site, rather than at the blade manufacturer.

This significantly reduces both costs and downtime while offering environmental savings.

Up until now, a wind turbine blade that suffered from loose or damaged bushings either had to be replaced entirely, or the damaged blade needed to be transported to the manufacturer for repair. This resulted in high logistics costs and long downtimes. Today, we can offer a repair solution directly at the wind park site. The blade root is equipped with threaded inserts – also called bushings – that join the rotor blade to the nacelle hub using blade studs.

These inserts can loosen over time. One cause is shrinkage of the polyester if used as resin. This can lead to microcracks, which endangers the bonding between the bushing and the blade and ultimately endangers the structural safety of the blade root. Bonding failure can lead to the loss of a blade and in worst case to a total turbine collapse. Our efficient blade root repair solution, developed together with We4Ce, an international blade rotor and blade root connection expert, allows the repair to be conducted on-site

TOTAL ECONOMY

Our root blade repair reduced costs as the damaged blade root bushings are repaired on-site with no logistic needed to transport the blade outside the wind park. The exact cost for a blade repair varies from blade to blade and depends mainly on the number of bushings affected and the location of the site. But it is always much cheaper than the standard methods involving off-site repairs or replacing the whole blade.

REDUCED DOWNTIME

With short downtime, the rotor blade can be mounted immediately once repaired, keeping lost production at a minimum.

SUSTAINABILITY

Using precision machining and the patented replacement bushings enable the repair on-site and the need for a potential new blade is avoided. Furthermore, rotor blades are not easily recyclable. Therefore the repair is not only a cheaper option, but it also has a much lower impact on the environment.

LIFETIME EXTENSION

The turbine life time can be extended, an advantage for older units. Finding a replacement blade for older turbines is often difficult and costs are mostly prohibitive. The low repair costs offer an alternative to scrapping the whole turbine and eliminates the reliance on obsolete rotors.

CONTACT US

Our team of experienced professionals will guide and advice you towards the
best possible solution that takes time, economy and durability into consideration.

Søren Kellenberger

Sales Director

+45 25 53 76 50 | ssk@cnconsite.dk

PROCESS

FROM CHALLENGE TO SOLUTION

Quotation request

Planning

Implementation

Handover

Follow-up

Quotation request

Wind turbine blade with damaged threaded bushings.

The wind park contacts us , reporting damage to the threaded bushings in the blade root.

We discuss with you the extent of the damage. determine if further actions are necessary to get the full picture of the damage

Based on the information, we will issue a quotation for the repair work.

The wind turbine owner approves the proposal and issues a purchasing order.

After that, we can begin the repair within days.

Planning

The rotor blade has been placed on the ground within the wind park. The blade inserts are visible

We plan the repairs together with our partner We4Ce.

The job is planned in detail with minimal disruption and downtime in mind.

Implementation

Wind turbine blade repair process using a portable CNC machine.

First, the rotor blade is dismounted and placed in a repair environment within the wind park. The repair area can be created on the ground for onshore wind farms or on the deck of a vessel for offshore wind farms.

Once the rotor blade is on the ground and placed in the repair environment, the repair work can start.

The portable pre-programmed CNC machine drills away the faulty bushings, matching the precise dimensions of the specialized replacement bushings, developed and patented by We4Ce.

New inserts are installed and fixed recreating the bond between the insert and the blade,

Upon completion, normally after a few days, the blade can be reinstalled and the turbine can be reinstalled and power production resumed.

Handover

CNC Onsite checklist and thumbs-up symbol, representing the efficient rotor lock repair process using in-house developed machines

When the repairs of the threaded bushings are complete, our technician discusses the final result with the customer, who approves and signs off.

We issue a repair report to the customer

Follow-up

As part of CNC Onsite’s high quality standards and professional approach, we offer to follow up on the repair job.

SOLUTIONS THAT FIT YOUR NEEDS

„We always take a total economic perspective on our solutions, ensuring that our customers get the most optimal solution in both the short and long term‟

Tobias Jakobsen, Project Engineer