Wind turbine blades with cap-assisted bond configuration and associated bonding method
A wind turbine blade ( 16 ) includes an upper shell member ( 20 ) and a lower shell member ( 22 ) with an internal cavity ( 25 ) therebetween. The shell members are joined with a bond paste ( 34 ) at respective bond lines ( 36, 37 ) along leading and trailing edges ( 24, 26 ) of the blade. A cap ( 50 ) is disposed within the internal cavity between the upper and lower shell members along at least one of the leading or trailing edge bond lines. The cap includes a head ( 52 ) oriented towards the blade edge and trailing leg portions ( 56 ) that span rearward from the head in biased engagement the upper and lower shell members. The cap defines a dam at the bond line against migration of excess bond paste further into the internal cavity. A method is also provided for forming bond lines at the leading or trailing edge with the bond paste caps.
1. A method for forming a bond between upper and lower shell members along at least one of the leading or trailing edges of a wind turbine blade, said method comprising:
placing an amount of bond paste along a defined bond line location of the leading or trailing edge;
placing a cap into one of the shell members at an initial position inboard of the bond paste along the bond line, the cap having a head oriented towards the leading or trailing edge and trailing leg portions that span rearward from said head, the trailing leg portions being straight and diverging from the head at a generally constant angle such that the head is defined as a point on the cap;
locating actuation lines attached to the cap head out from the shell member beyond the leading or trailing edge;
joining the shell members together along the leading and trailing edges such that the trailing leg portions of the cap are biased against the shell members;
pulling the actuation lines to move the cap towards the leading or trailing edge to an operational position that defines a desired bond width location; and
wherein the cap defines a dam against migration of the bond paste into the internal cavity of the blade and the trailing leg portions compressing the bond paste and causing excess bond paste to be forced out from the leading or trailing edge as the cap is pulled towards its operational position.
2. The method as in claim 1 , further comprising trimming excess bond paste that migrated out from the leading or trailing edge.
3. The method as in claim 2 , further comprising measuring the amount of excess bond paste trimmed from the leading or trailing edge and reducing the amount of bond paste initially placed into a subsequent blade by the measured amount of trimmed bond paste.
4. The method as in claim 1 , wherein the cap is applied along the trailing edge.
5. The method as in claim 1 , further comprising forming the cap into a stiff, pre-formed shape prior to placing the cap into the shell member.
6. The method as in claim 1 , further comprising trimming the actuation lines at the leading or trailing edge.