Pultruded strips

Patent metadata

Field	Value
Publication number	US-11858225-B2
Application number	US-201816607786-A
Country	US
Kind code	B2
Filing date	May 8, 2018
Priority date	May 9, 2017
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

A pultruded strip ( 50 ) of reinforcing material for stacking with one or more similar strips ( 50 ) to form a spar cap for a wind turbine blade is disclosed. The pultruded strip comprises a core ( 56 ) comprising fibres ( 58 ) disposed in a resin matrix ( 60 ) and a sacrificial layer ( 52 ) at least partially covering one or more surfaces of the core ( 56 ). The sacrificial layer ( 52 ) is a resin layer defining an adherend surface ( 62 A) of the strip. A pultrusion process for making such a strip ( 50 ) comprises drawing resin-coated reinforcing fibres ( 58 ) through a pultrusion die ( 80 ) in a process direction to form a core ( 56 ) of the strip ( 50 ) and applying further resin ( 53 ) to one or more surfaces of the core ( 56 ) to form a sacrificial resin layer ( 52 ) defining an adherend surface ( 62 A) of the strip ( 50 ).

First claim

The invention claimed is:

1. A pultrusion process for making a pultruded strip suitable for stacking with one or more similar strips to form a spar cap for a wind turbine blade, the process comprising:
drawing resin-coated reinforcing fibres through a pultrusion die in a process direction to form a core of the strip;
applying further resin to one or more surfaces of the core to form a sacrificial resin layer defining an adherend surface of the strip; and
removing resin from the sacrificial layer through a surface treatment process to activate the adherend surface.

2. The pultrusion process of claim 1 , further comprising at least partially curing the resin in the core of the strip before applying the further resin.

3. The pultrusion process of claim 1 , comprising applying the further resin downstream of the pultrusion die in the process direction.

4. The pultrusion process of claim 1 , wherein the method comprises drawing the core with the applied further resin through a further pultrusion die to form the strip into a final cross-sectional shape.

5. The pultrusion process of claim 1 , further comprising shaping the core of the strip in a first portion of the die and shaping the core and sacrificial layer in a second portion of the die, wherein the method comprises applying the further resin to the core within the die between the first and second portions of the die.

6. A pultruded strip of reinforcing material for stacking with one or more similar strips to form a spar cap for a wind turbine blade, the pultruded strip comprising:
a core comprising fibres disposed in a resin matrix; and
a sacrificial layer at least partially covering one or more surfaces of the core, wherein the sacrificial layer is a resin layer defining an adherend surface of the strip; and
wherein the sacrificial layer has an activated adherend surface formed by using a surface treatment process to remove resin from the sacrificial layer.

7. The pultruded strip of claim 6 , wherein the sacrificial layer is substantially devoid of fibres.

8. The pultruded strip of claim 6 , wherein the sacrificial layer has a thickness in the range of 0.1 mm to 2 mm.

9. The pultruded strip of claim 6 , wherein the sacrificial resin layer comprises a resin that is different to the resin in the core.

10. The pultruded strip of claim 6 , wherein the sacrificial layer is provided on mutually opposed first and second surfaces of the core.

11. A spar cap for a wind turbine blade, the spar cap comprising a stack of pultruded strips integrated together, wherein each strip is a pultruded strip as claimed in claim 6 .

12. The spar cap of claim 11 , wherein an adherend surface of each strip is bonded to an adherend surface of an adjacent strip in the stack by adhesive such as cured resin.

13. A wind turbine blade comprising the spar cap claim 12 .

14. The pultrusion process of claim 1 , wherein the surface treatment process includes at least one of an abrasion process, a blasting treatment process, or an energetic surface treatment process.

15. The pultrusion process of claim 1 , wherein the one or more surfaces to which the resin is applied extend an entire width of the strip.

16. The pultrusion process of claim 15 , wherein the one or more surfaces that extend the entire width of the strip are planar surfaces.

Assignees

• Vestas Wind Sys As

Inventors

• D'Alesio Alessio

Classifications

• B29C70/521 Primary

  and impregnating the reinforcement before the die · CPC title

• B29B11/06

  by moulding the material · CPC title

• B29B11/16

  comprising fillers or reinforcement {(non-woven fabrics per se D04H1/00, D04H3/00)} · CPC title

• B29D99/0003

  Producing profiled members, e.g. beams · CPC title

• F03D1/0675

  of the blades · CPC title