Method for manufacturing a hollow composite structure, particularly a spar beam for a wind turbine rotor blade, and an associated mandrel

• Main Authors: Yarbrough, Aaron A, Shillig, Scott Iverson, Rondeau, Louis, Chen, Xu
• Format: Patent
• Language: English
• Published: 23.01.2024
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BLASTING; HEATING; LIGHTING; MACHINES OR ENGINES FOR LIQUIDS; MECHANICAL ENGINEERING; OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; PRODUCING MECHANICAL POWER; PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCESIN A PLASTIC STATE; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WEAPONS; WIND MOTORS; WIND, SPRING WEIGHT AND MISCELLANEOUS MOTORS; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

A method for producing a hollow composite structure, such as a spar beam for use in a wind turbine blade, includes placing fiber reinforcement material around a mandrel within a mold, and curing the fiber reinforcement material. The mandrel is formed from a compressible material having a rigid neutral state with a rigidity to maintain a defined shape of the mandrel during lay up and curing of the fiber reinforcement material. Subsequent to curing, a vacuum is drawn on the mandrel to compress the compressible material so that the compressed mandrel can be drawn out through an opening in the composite structure, the opening having a size such that the mandrel could not be withdrawn through the opening in the rigid neutral state of the mandrel.