This need came from Ahlstrom-Munksjö customers, who are trying to tackle the challenge of the ever-increasing size of wind turbine blades. While blades become longer, also the thickness of laminates gets higher.

Ahlstrom-Munksjö (Finland) glass and carbon fiber composite team was able to develop a carbon fiber based unidirectional fabric. In a unidirectional (UD) fabric the majority of fibers run in one direction only. The new fabric developed, can be laminated to 165 layers or even more in one shot. The previous record of infusing carbon fiber unidirectional fabric was 120 layers.

"We are really excited about the new HighFlow Carbon unidirectional fabric. Our team in Mikkeli plant, Finland, did excellent work with this. ", says Pekka Helynranta, Vice President, Building & Wind. "HighFlow Carbon Wind Energy is specially designed for wind turbine blades to enable larger new generation wind turbines."

Bigger wind turbines can generate more energy. Increase in size means also increase in blade size. To optimize power generation blades should be lightweight and stiff. Until now, there wasn’t a good solution to this. HighFlow Carbon solves this problem. By increasing the number of unidirectional fabric layers up to 165 we are able to help the customer to reach a new level of thickness on spar cap laminates. The fabric was unidirectional carbon fiber 600g/m2.

By using Ahlstrom-Munksjö HighFlow fabrics, the infusion process itself is more reliable as there is a lower risk for unsaturated areas of carbon unidirectional fabric. In this new range of products the permeability of fabrics is totally engineerable, the flow rate and direction can be controlled. This means that our customers can now forget problems related to infusion of carbon fiber fabrics.

They have reached a high level of interest from customers. The customers are turbine blade manufacturers which use the blades on their own turbines or sell the blades to the big global wind turbine manufacturers. Also, design offices, which make blade designs for blade manufacturers have shown interest in our new concept.