General Electric Company
METHOD FOR MANUFACTURING A HOLLOW COMPOSITE STRUCTURE, PARTICULARLY A SPAR BEAM FOR A WIND TURBINE ROTOR BLADE, AND AN ASSOCIATED MANDREL

Abstract:

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drawn out through an opening in the composite structure, the opening having a size such that the mandrel could not be withdrawn through the opening in the rigid neutral state of the mandrel.