Patent ID: 11878444
Assignee: GE INFRASTRUCTURE TECHNOLOGY LLC
Field: Other special machines (Mechanical engineering)
Classification: CPC B  F  Y | IPC B  F

Claim 0:
1. A method for producing a hollow composite structure, comprising:
placing fiber reinforcement material within a mold, an inner surface of the mold defining a desired shape of the composite structure;
placing a mandrel in the mold over the fiber reinforcement material, the mandrel comprising a continuous compressible material in an uncompressed neutral state arranged completely around a core component that is more or less compressible than the compressible material;
maintaining the neutral state of the compressible material uniformly and completely around the core component in a defined shape corresponding to the desired shape of the composite structure defined by the mold, the compressible material having a rigidity in the neutral state to maintain the defined shape during layup and curing of the fiber reinforcement material completely around the mandrel;
after placement of the mandrel, wrapping the fiber reinforcement material completely around the mandrel while maintaining the neutral state of the compressible material uniformly and completely around the core component;
curing the fiber reinforcement material with a resin;
subsequent to curing, drawing a vacuum on the mandrel to compress the compressible material from the neutral state to a compressed state; and
withdrawing the mandrel including the compressible material in the compressed state and the core through an opening in the composite structure, the opening having a size such that the mandrel could not be withdrawn through the opening in the rigid neutral state of the mandrel.