World's largest carbon belt created using infusion technology with SAERTEX

Cooperation between SAERTEX®, WINDnovation, COMPOSYST and CTP AM

SAERTEX is pleased to announce its contribution to the production of an innovative prototype for the rotor blade of a wind turbine. This is probably the longest and thickest carbon fiber belt ever produced using the vacuum infusion process.

In April 2019, a Chinese manufacturer of rotor blades for wind turbines successfully completed the production of an 87.5 m long rotor blade chord. The chord is one of the key structural elements that absorbs the majority of the mechanical loads in a rotor blade. The new record-breaking chord was made from carbon fibers in order to reduce the component weight and achieve greater rigidity. Both are crucial for rotor blades of this length.

The design of the rotor blade belt was developed by WINDnovation. Due to its dimensions, length (87.5 m) and width (800 mm), the production of the belt posed a number of technical challenges. Carbon reinforcement materials of type UD618gsm (unidirectional fabric) with an increased Z-permeability of SAERTEX were used for production. These were specially developed for the infusion of large laminate thicknesses and made it possible to use the latent resin system 3325 A/B from CTP AM with optimized viscosity and longer pot life.

The infusion of the belt was carried out using VAP technology with the VAP membrane from COMPOSYST. This process enables degassing of the resin during the entire infusion, facilitates resin distribution and regulation of the resin content throughout the component and makes the process safer.

The infusion process itself took less than two hours and there were no problems whatsoever. After curing and demolding on the following day, the entire team was delighted to have an almost perfect component with no defects. The production of the prototype was technically supported by SAERTEX, WINDnovation, COMPOSYSt and CTP AM.