Wind turbine blade and a method of moulding a wind turbine blade tip section
A wind turbine blade and a method of moulding a wind turbine blade tip section. The overall wind turbine blade has an elongate structure extending in a radial sense in a finished wind turbine. The blade comprises a fairing that one is supported along its length by a spar extended along the full length of the fairing from the root end to the tip. The fairing is in two parts with a main part extending from the root for most the of the longitudinal length of the blade and the tip section forming the remainder of the blade.
1. A method of moulding a wind turbine blade tip section, the method comprising:
laying up a first composite material into a first mould half;
laying up a second composite material into a second mould half;
providing at least one of the first and second mould halves with an extension, the extension defining a series of transitional steps;
laying up at least one of the first and second composite materials across the extension to form a corresponding first series of transitional steps into at least one of the first and second composite materials, wherein the other of the at least one of the first and second composite materials comprises a corresponding second series of transitional steps;
removing the extension before bringing the mould halves together;
after removal of the extension, bringing the first and second mould halves together so that the first and second composite materials overlap where the first and second mould halves meet, wherein overlapping portions of first and second composite materials comprise corresponding first and second series of transitional steps being arranged together in a stepped configuration;
supporting the overlapping portions of first and second composite materials with a pressure bag; and
curing the first and second composite materials simultaneously so that matrices of the first and second composite materials fuse together where the first and second composite materials overlap.
2. The method according to claim 1 , further comprising co-moulding a first spar cap in the first mould half and co-moulding a second spar cap in the second mould half.
3. The method according to claim 2 , wherein the spar caps protrude from the tip section.
4. The method according to claim 1 , wherein at least one pressure bag is inserted into the mould halves in order to support the first and second composite materials during the curing process.
5. The method according to claim 1 , further comprising co-moulding a shear web between spar caps of the wind turbine blade tip.
6. The method according to claim 1 , further comprising:
insetting a trailing edge core former piece into the mould halves; and
wrapping one of the first and second composite materials across one surface of the former piece and at least partially across an opposite surface of the former piece where at least one of the first and second composite materials terminates in a transitional region; and
bringing the other of the first and second composite materials into engagement with the transitional region when the mould halves are brought together.
7. The method according to claim 1 , wherein the blade tip section is at least 10 meters long.
8. The method according to claim 2 , wherein at least one pressure bag is inserted into the mould halves in order to support the first and second composite materials during the curing process.
9. The method according to claim 3 , wherein at least one pressure bag is inserted into the mould halves in order to support the first and second composite materials during the curing process.