Wind turbine blade handling aboard a vessel

Abstract

A method is provided for handling wind turbine blades aboard a vessel, the method including providing on the vessel a blade rack assembly configured to accommodate more than one blade, the rack assembly having at least a root rack and a tip rack, and the root rack and tip rack defining between them a blade support plane. The method also includes providing a jack acting between the vessel and one of the root or tip rack; and raising or lowering one of the root or tip rack aboard the vessel by the jack to thereby move the blade support plane through an elevation angle θ. A jack assembly on a wind turbine installation vessel and an offshore wind turbine installation vessel are also provided, each capable of raising or lowering a rack of wind turbine blade root or tip support frame elements.

The invention claimed is: 
     
       1. A method for handling wind turbine blades aboard a vessel, said method comprising:
 providing on said vessel a blade rack arrangement configured to accommodate more than one blade, said rack arrangement comprising at least a root rack and a tip rack, wherein said root rack and said tip rack between them define a blade support plane; 
 providing a jack including a drive device acting between said vessel and at least one of a lifting platform or a rotatable rack spacer associated with one of said root rack or tip rack; and 
 raising or lowering one of said root rack or tip rack aboard said vessel by means of said jack to thereby move said blade support plane through an elevation angle. 
 
     
     
       2. The method according to  claim 1 , wherein the other one of said root rack or tip rack is substantially not raised or lowered. 
     
     
       3. The method according to  claim 1 , wherein the other one of said root rack or tip rack is positioned atop a static base frame and is thereby supported at a height above a loading deck of said vessel. 
     
     
       4. The method according to  claim 1 , each said root rack or tip rack being comprised of a root frame element or tip frame element, each frame element being configured to support a respective root portion or tip portion of a single blade and each root frame element or tip frame element being separably connectable to one or more adjacent frame elements in said root rack or tip rack. 
     
     
       5. The method according to  claim 1 , additionally comprising providing a pivot under the other one of said root rack or tip rack. 
     
     
       6. The method according to  claim 1 , wherein said jack comprises said rotatable rack spacer, wherein said rotatable rack spacer is capable of rotating between a lowered support position and a raised support position. 
     
     
       7. The method according to  claim 1 , wherein said elevation angle through which said blade support plane is moved is of at least three degrees. 
     
     
       8. The method according to  claim 1 , further including providing a connecting boom between said root rack and said tip rack. 
     
     
       9. A jack on a wind turbine installation vessel capable of raising or lowering a rack of wind turbine blade root support frame elements or tip support frame elements of the blade rack arrangement, according to the method of  claim 1 , said jack comprising said lifting platform driven by said drive device and being positionable at one of said root rack or tip rack to be raised or lowered. 
     
     
       10. The jack according to  claim 9 , said jack further comprising a pivot positionable at the other one of said root rack or tip rack of said rack arrangement. 
     
     
       11. The jack according to  claim 9 , comprising a pivot rotatably coupled to said lifting platform by a coupling linkage. 
     
     
       12. The jack according to  claim 9  wherein said drive device is a linear drive and is coupled to said rotatable rack spacer, said rack spacer being rotatably coupled to a pivot joint at said rack and being rotatably coupled to said linear drive. 
     
     
       13. The jack according to  claim 12  wherein said rotatable rack spacer is configured to exhibit a raised rack support position and a lowered rack support position and wherein said jack assembly is configured to rotate said rotatable rack spacer between said raised rack support position and said lowered rack support position by means of said linear drive. 
     
     
       14. An offshore wind turbine installation vessel comprising a loading deck, a crane and the jack according to  claim 9 . 
     
     
       15. A method for handling wind turbine blades aboard a vessel, said method comprising:
 providing on said vessel a blade rack arrangement configured to accommodate more than one blade, said rack arrangement comprising at least a root rack and a tip rack, wherein said root rack and said tip rack between them define a blade support plane; 
 providing a jack acting between said vessel and one of said root rack or tip rack, wherein said jack comprises a linear drive operatively coupled to said vessel proximate a first end of said linear drive and pivotably coupled to at least one of a lifting platform or a rotatable rack spacer proximate a second end of said linear drive; and 
 raising or lowering one of said root rack or tip rack aboard said vessel by means of said jack to thereby move said blade support plane through an elevation angle.