Patent ID: 7988805

Claim:
A process for manufacturing a vane or rotor blade for a wind powered generating unit, comprising the steps of: producing a structural element ( 10 ) comprising a plurality of body segments ( 11 ) arranged adjacent to one another in a plane and interconnected comprising the following steps: a) manufacturing of close-cell rod-shaped or column-shaped foamed plastic bodies ( 7 ) having long sides; b) welding together the long sides of the rod-shaped or column-shaped foamed bodies ( 7 ) into a plastic block ( 5 ) thus creating weld seams ( 32 , 33 ) over a face, whereby the said weld seams ( 32 , 33 ) are present as substantially pore-free intermediate plastic layers to form a block of foamed plastic; and c) dividing the block ( 5 ) of foamed plastic into individual structural elements ( 30 ) comprising foam sheets, running transverse or perpendicular to the longitudinal direction of the foam bodies ( 7 ), wherein the rod-shaped or column-shaped foam bodies ( 7 ) are manufactured using a polymer chain structure that is stretched in a direction of extrusion, and wherein the direction of extrusion is the longitudinal direction of the foam bodies, whereby the weld seams ( 32 , 33 ), as viewed in plan view of the structural element ( 30 ), form a network like structure of struts defined by intersecting weld seams, and wherein the structural element is a plastic sheet having opposed relatively large area sides, and relatively small area edges, and where the stretched polymer structure is in a direction perpendicular to the relatively large area sides; and incorporating the structural element into the vane or rotor blade of a wind powered generating unit.