Pultrusion of Profiles Having Non-Uniform Cross Sections
Composite profiles, such as rotor blades, airfoils, I-beams, and box beams having non-uniform cross sections, and a system, method and process for pultrusion of composite profiles. The pultrusion of a heavier or thicker cross section portion of the composite profile is performed in-line and upstream from pultrusion of a thinner or lighter portion of the pultruded profile using a separate die for the thicker portion of the cross section, or leading edge slug, in order to optimize the processing conditions, productivity, and consistency of the composite profiles.
1 . A method for pultrusion of a composite profile having a non-uniform cross section comprising:
providing a leading edge slug die for pultruding a leading edge slug of the composite profile;
providing a primary pultrusion die downstream from the leading edge slug die for pultruding a profile body of the composite profile;
threading a first set of fibers into the leading edge slug die;
threading a second set of fibers into the primary pultrusion die;
heating the leading edge slug die;
heating the primary pultrusion die;
adding a first resin to a leading edge slug wet out bath;
pulling the first set of fibers and the first resin through the leading edge slug die to form the leading edge slug;
adding a second resin to a main wet out bath; and
integrating the leading edge slug with the profile body to form the composite profile by pulling the leading edge slug through the primary pultrusion die while pulling the second set of fibers and the second resin through the primary pultrusion die to form the profile body.
2 . The method of claim 1 wherein pulling the first set of fibers and the first resin through the leading edge slug die to form the leading edge slug further comprises inserting a wire rope for forming a leading edge weight insert.
3 . The method of claim 1 further comprising partially curing the leading edge slug with the leading edge slug die.
4 . The method of claim 3 further comprising completing curing of the leading edge slug with the primary pultrusion die.
5 . A composite profile having a non-uniform cross section manufactured by a process comprising the steps of:
providing a leading edge slug die for pultruding a leading edge slug of the composite profile;
providing a primary pultrusion die downstream from the leading edge slug die for pultruding a profile body of the composite profile;
threading a first set of fibers into the leading edge slug die;
threading a second set of fibers into the primary pultrusion die;
heating the leading edge slug die;
heating the primary pultrusion die;
adding a first resin to a leading edge slug wet out bath;
pulling the first set of fibers and the first resin through the leading edge slug die to form the leading edge slug;
adding a second resin to a main wet out bath; and
integrating the leading edge slug with the profile body to form the composite profile by pulling the leading edge slug through the primary pultrusion die while pulling the second set of fibers and the second resin through the primary pultrusion die to form the profile body.
6 . The composite profile manufactured by the process of claim 5 wherein the first resin comprises a vinyl ester resin and the second resin comprises an epoxy resin.
7 . The composite profile manufactured by the process of claim 5 wherein the first set of fibers comprises carbon fibers and the second set of fibers comprises glass fibers.
8 . The composite profile manufactured by the process of claim 5 further comprising inserting a wire rope into the leading edge slug for forming a leading edge weight insert.
9 . The composite profile manufactured by the process of claim 5 further comprising partially curing the leading edge slug with the leading edge slug die.
10 . The composite profile manufactured by the process of claim 9 further comprising completing curing of the leading edge slug with the primary pultrusion die.
11 . A pultrusion tooling system for pultruding a composite profile having a non-uniform cross section comprising:
a leading edge slug die for pultruding a first portion of the composite profile having a first cross section thickness;
a primary pultrusion die for pultruding a second portion of the composite profile having a second cross section thickness, wherein the second cross section thickness is less than the first cross section thickness;
a leading edge wet out bath for adding a first resin to the first portion of the composite profile;
a mandrel for shaping the second portion of the composite profile;
an overwrap infeed tool for wrapping fibers around the mandrel; and
a main wet out bath for adding a second resin to the second portion of the composite profile.
12 . The pultrusion tooling system of claim 11 further comprising a wire rope spool for inserting a wire rope into the first portion of the composite profile.
13 . The pultrusion tooling system of claim 11 wherein a length of the leading edge slug die is greater than a length of the primary pultrusion die.