BLADE FOR A WIND TURBINE
A blade for a wind turbine comprising a blade root portion is described. The blade root portion defines an mounting surface for coupling to a hub or extender of the wind turbine and comprises a plurality of first holes provided with an insert, the blade root portion further comprises a mounting flange arranged in the periphery of the mounting surface and provided with second holes, wherein the inserts comprise a first end embedded in the blade root portion and a second end opposite to said first end, the second end protruding beyond the mounting surface of the blade root portion, and wherein the second ends are fitted in the second holes of the mounting flange and the mounting flange is attached to the blade by means of the inserts. Furthermore, a wind turbine rotor comprising such a blade is described. Methods of manufacturing half a wind turbine blade and a whole wind turbine blade are also described.
1 . A blade for a wind turbine, comprising:
a blade root portion, the blade root portion defining a mounting surface for coupling to a hub or extender of the wind turbine,
the blade root portion comprising a plurality of first holes provided with an insert,
the blade root portion further comprising a mounting flange arranged in the periphery of the mounting surface and provided with second holes,
wherein the inserts comprise a first end embedded in the blade root portion and a second end opposite to the first end, the second end protruding beyond the mounting surface of the blade root portion, and
wherein the second ends are fitted in the second holes of the mounting flange and the mounting flange is attached to the blade by the inserts.
2 . The blade according to claim 1 , wherein the mounting flange is attached to the blade only by the inserts.
3 . The blade according to claim 1 , wherein one or more second ends of the inserts and an inner side of the corresponding second holes comprise a straight shape and an inner diameter of the second holes is slightly smaller than an outer diameter of the second ends of the inserts.
4 . The blade according to claim 1 , wherein one or more second ends of the inserts comprises an outer surface having a tapered shape.
5 . The blade according to claim 1 , wherein one or more second ends of the inserts comprises a protrusion extending in a plane substantially perpendicular to that of a longitudinal axis of the insert and an inner side of the corresponding second holes comprises an indentation in which the protrusion can be positioned.
6 . The blade according to claim 1 , wherein one or more second ends of the inserts comprises a threaded portion and an inner side of the corresponding second holes comprises an indentation in which a nut, matching the threaded portion, can be inserted.
7 . The blade according to claim 1 , wherein one or more second ends of the inserts comprises an external thread and an inner side of the corresponding second holes comprises a thread that is complementary to the external thread of the inserts.
8 . The blade according to claims 1 , wherein the inserts are welded to the second holes.
9 . A wind turbine rotor comprising a hub and at least one blade according to claim 1 .
10 . A method of manufacturing a wind turbine blade half, the method comprising the steps of
joining a plurality of inserts to half a mounting flange;
arranging the resulting assembly of inserts-half mounting flange together with fibres in a mould;
introducing resin in the mould; and
curing the resin, such that the assembly of inserts-half mounting flange is joined to the resin and fibres.
11 . A method of manufacturing a wind turbine blade comprising manufacturing two blade halves using a method according to claim 10 , and joining the two blade halves.
12 . A wind turbine rotor comprising a hub and at least one blade according to claim 2 .
13 . A wind turbine rotor comprising a hub and at least one blade according to claim 3 .
14 . A wind turbine rotor comprising a hub and at least one blade according to claim 4 .
15 . A wind turbine rotor comprising a hub and at least one blade according to claim 5 .
16 . A wind turbine rotor comprising a hub and at least one blade according to claim 6 .
17 . A wind turbine rotor comprising a hub and at least one blade according to claim 7 .
18 . A wind turbine rotor comprising a hub and at least one blade according to claim 8 .