Method for preventing edge layering of wind power blade and wind power blade

Abstract

The invention relates to the field of wind power blades, and discloses a method for preventing edge layering of a wind power blade and the wind power blade. The method comprises the steps that a three-dimensional model of the wind power blade is corrected according to a target molded surface of the wind power blade, and the molded surface of a mold is deepened to form a groove within the preset length range of a parting line of the front edge and the rear edge of the blade; an edge layering prevention structure is formed by the supporting layer, the elastic layer and the interface layer; a glass fiber reinforced plastic layer of the mold is formed by adopting a fractional pouring process, so that the edge layering prevention structure and the mold body are integrally formed; wherein in the pouring process, the supporting layer and the elastic layer are sequentially arranged in the groove, and then fiber cloth laying and resin pouring are carried out; after the mold glass fiber reinforced plastic shell is formed, interface layers are arranged in designated areas of the front edge and the rear edge of the mold glass fiber reinforced plastic shell to form a low-surface-energy interface. On the premise that the pneumatic profile precision of the blade is guaranteed, layering damage to the edge of the mold closing seam is eradicated, meanwhile, the production efficiency is remarkably improved, and the material and labor cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wind power blades, in particular to a method for preventing wind power blade edge delamination and a wind power blade. BACKGROUND

[0002] As a member of new energy, wind energy has the advantages of large capacity and mature technology, and has developed rapidly in recent years with the support of governments around the world. In order to improve the energy capture efficiency, the single machine capacity of wind turbines is getting larger and larger, from 500kW in 20 years to 12MW commercial wind turbines today.

[0003] The wind power blade is an important part of the wind turbine generator set. After the introduction of new composite materials into the design and manufacturing field of wind power blades, the manufacturing process of wind power blades has also changed greatly. From the perspective of wind power blade design, considering the various requirements of wind power blades put forward by the working conditions and performance requirements of wind turbine generators, the difficulty of the whole design is relatively large. From the perspective of wind power blade manufacturing, on the basis of effective processing materials, optimizing the manufacturing process of wind power blades and ensuring the actual performance of wind power blades are of great significance to the normal operation of wind power blades and wind turbine generators.

[0004] From the perspective of the manufacturing process of composite blades, the optimization of the manufacturing process is an important link of the whole process optimization. On the mold, a series of parts such as the main beam and the skin of the blade are formed, which is the first link of the whole blade manufacturing. After the manufacturing of various parts is completed, the assembly of the parts is needed, and finally the mold is cured to form the wind power blade.

[0005] In the mold design, in order to ensure the consistency of the product contour with the design, only a small demolding angle or round angle is designed for the edge. The edge of the wind power blade often has problems such as stress deformation or demolding difficulty, and the edge structure is often damaged during the demolding process of the parts or skin, causing delamination damage of the parts or products. Therefore, a lot of time and labor are needed for maintenance and treatment.

[0006] With the rapid development of the wind power industry, the length of the blade has developed from 40m to more than 100m, and the diameter of the blade root has developed from 2m to more than 4m. In the manufacturing of large wind power blades, the damage degree and maintenance of defects have become increasingly sensitive and concerned. From the perspective of production management, how to eliminate defect problems and avoid defects through technical means is of great significance to product quality and safety.

[0007] If the mold can be improved, the mold design can be optimized, and a separate structure can be arranged at the edge part, both the product contour can be guaranteed, and the deformation caused by the mold deformation in the forming process can be released, the layered damage to the part and the skin edge will not be caused in the demolding stage, and the wind power blade forming efficiency and quality can be greatly improved.

[0008] CN119348185A discloses a method for controlling the layered joint of a wind power blade, and a wind power blade. The method is as follows: a PTFE film is pasted into a type cavity from a prism of a mold at a joint position, then glass cloth and porous film are alternately laid on the surface of the PTFE film, and a foam material repair strip is used on one layer of glass cloth to create a barrier interface, and finally, pouring and demolding are completed. When cooled and shrunk, the product is first separated from the interface, thereby avoiding the concentrated stress directly acting on the product itself, achieving the purpose of controlling the layered joint of the wind power blade and improving the quality of the blade. However, such a method will damage the blade surface by using the pad cloth, and additional compensation for the corresponding structure layer is required.

[0009] CN119261235A discloses a method for controlling the layered joint of a wind power blade. A groove is provided at the front edge joint and the rear edge joint of the blade mold adjacent to the blade root point, and silica gel is embedded in the groove. The top surface of the silica gel is flush with the surface of the blade mold or has an exposed height a, and a<5h; wherein h is the thickness of a single layer of pad cloth. By increasing the silica gel at the front and rear edges of the blade mold, a buffer is formed between the blade and the mold during the joint of the blade, the laminated structure of the joint of the blade is protected, and the layered defect of the joint is reduced or even eliminated. In addition, the silica gel can be recycled, and only needs to be replaced once every 20-30 blade production time. Compared with the consumption of glass fiber, resin and labor of the pad cloth, the production cost of the blade is reduced. Such a method will affect the air tightness of the mold, and the silica gel will be released after heating. After the volatile diffusion of the silicone oil, it will enter the fiber structure layer, which will cause potential risks such as layering of the structure layer.

[0010] CN117601462A discloses a wind turbine blade and a wind turbine blade product mold joint position layered defect solving method, wherein the method comprises the following steps: applying release agent in the blade shell mold; laying multiple layers of glass cloth on the front and rear edges of the blade shell mold root area; laying a pre-separation layer on the front and rear edges of the blade shell mold root area; laying release cloth on the front and rear edges of the blade shell mold root area; laying a blade layup in the blade shell mold; pouring glass steel into the mold and pre-solidifying; opening the pre-separation layer to make the inside of the pre-separation layer communicate with the atmosphere, so that the blade shell is separated from the mold; and the pre-separation layer is laid between the glass cloth and the release cloth before pouring the wind turbine blade product, and after pre-solidification, the pre-separation layer is opened to make air enter between the wind turbine blade product and the mold, thereby solving the layering problem of the wind turbine blade product in the bonding and post-solidification stages. However, this method may affect the blade root roundness and the corresponding screw hole position, which is not conducive to controlling the overall base circle shape of the blade root.

[0011] Large wind turbine blades have reached more than one hundred meters, and edge delamination of components and skins is easy to cause corresponding area delamination, and even lead to structural fracture. The current technical level often uses changing the layup or increasing the "sacrificial layer" design to reduce or eliminate edge delamination, such as improving the mold structure design, which does not affect the production process and the formed structure, ensures the stability of the structure design, and is of great significance to the quality of the blade product.

[0012] At present, in order to control the edge delamination of wind turbine blade components and products, the following methods are often used for comprehensive control: 1) A large enough fillet is designed at the edge of the component product, and the corresponding component or product edge structure layer is adjusted.

[0013] 2) A pad or gasket is arranged in the corresponding wind layer area, and the delamination area is transferred through an elastic sheet or "sacrificial layer" structure.

[0014] However, the above two methods consume more time and materials, and it is difficult to completely prevent and control, which may cause repeated work in multiple places. SUMMARY

[0015] In view of the above technical deficiencies, the technical problem to be solved by the present application is to provide a method for preventing edge delamination of a wind turbine blade and a wind turbine blade, aiming to solve the problems of large material and time consumption, poor process controllability, and possible influence on the quality of the blade profile caused by relying on one-time "sacrificial layer" or temporary pad cloth and other methods in the manufacture of existing wind turbine blades.

[0016] To solve the above technical problems, the present application adopts the following technical scheme: the present application provides a method for preventing edge delamination of a wind turbine blade, comprising: According to the target profile of the wind turbine blade, the three-dimensional model of the wind turbine blade is corrected, the mold profile is deepened to form a groove in the length range of the front and rear edge parting lines of the blade, and a transition chamfer is processed in the axial and chordal directions of the groove; The support layer, the elastic layer and the interface layer form the anti-edge delamination structure. The glass steel layer of the mold is formed by a split perfusion process, so that the anti-edge delamination structure is integrally formed with the mold body. In the perfusion process, the support layer and the elastic layer are sequentially arranged in the groove, and then the fiber cloth is laid and the resin is perfused; after the mold glass steel shell is formed, the interface layer is arranged in the specified area of the front and rear edges to form a low surface energy interface.

[0017] Further, the material of the support layer is butyl rubber or thermoplastic elastomer, the hardness is 55HD~70HD, and the thickness is 3~5mm, and the surface of the support layer is mechanically polished and chemically activated.

[0018] Further, the material of the elastic layer is high-density polyurethane or fluorine rubber, the hardness is 35HD~55HD, and the profile change under one atmosphere is 2±1mm.

[0019] Further, the interface layer is a polytetrafluoroethylene film or a fluorine-containing gel coat.

[0020] Further, the support layer and the elastic layer are connected by a mechanical connector or an adhesive, and the interface layer is arranged on the surface of the elastic layer by film adhesion or coating.

[0021] Further, the preset length is 0% to 25% of the length of the front and rear edge parting lines; The depth of the deepening of the mold profile is 3~5mm; The ratio of the transition chamfer is 1:10.

[0022] Further, the split perfusion process includes: First perfusion, lay surface felt and bidirectional fiber cloth on the surface of the mold model, and lay release cloth to form a basic profile; Second perfusion, place the support layer and the elastic layer in the groove on the formed basic profile, then lay multiple layers of glass fiber cloth, perfuse and cure to form a mold main shell containing the anti-edge delamination structure main body; Third perfusion, arrange a heating system on the mold main shell and perfuse; Fourth perfusion, lay a structural layer on the heating system and perfuse to form a complete mold glass steel layer.

[0023] Further, the volume shrinkage of the epoxy resin system used in the mold forming process is not greater than 4.5%, and the type of glass fiber impregnant is matched with the selected resin.

[0024] Further, the steel structure is connected on the glass steel layer of the mold after the pouring forming, and the whole is turned over.

[0025] A wind power blade is manufactured by a method for preventing wind power blade edge delamination.

[0026] The method of the present application has the advantages that: the present application forms a low surface energy high elasticity interface by completing the predetermined shaping in the model processing stage of the mold and manufacturing when the glass steel profile area of the mold is designed and processed, effectively eliminates stress deformation, releases mold stress, ensures that the product edge is not affected by the mold stress to produce delamination defects, realizes the method of not reducing production efficiency, improving forming quality and reducing production labor, eliminates the backward method of placing a sacrificial layer, improves product quality while shortening the molding cycle, and the present application has the characteristics of simple design form, clear manufacturing route, reliable product quality and high efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0028] Figure 1 The schematic diagram of the edge delamination prevention structure provided by the present application is shown.

[0029] The reference signs are explained: 1, interface layer; 2, elastic layer; 3, support layer. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be described clearly and completely in the following with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0031] The present embodiment provides a method for preventing wind power blade edge delamination, comprising: According to the target profile of the wind power blade, the three-dimensional model of the wind power blade is corrected, the mold profile is deepened to form a groove in the length range of the split line of the front and rear edges of the blade, and a transition chamfer is processed in the axial and chordal directions of the groove; As shown in Figure 1 The edge anti-layering structure is composed of a support layer, an elastic layer and an interface layer. It should be noted that: The edge anti-layering structure is composed of multiple layers of high-elasticity materials with low surface energy. Among them, there are support layer, elastic layer and interface layer. Among the three functional layers, the support layer and the elastic layer can be connected by mechanical methods such as bolts and screws, or connected by adhesive methods, and the interface layer is arranged by film bonding or coating. The support layer is mainly made of butyl rubber, thermoplastic elastomer and other materials, which has a certain hardness, generally 55HD~70HD, and its surface is activated by mechanical polishing and chemical surface activation, so that it is integrated with the elastic layer. The thickness of the support layer is 3~5mm. The elastic layer is made of high-density polyurethane material or fluororubber material, and the corresponding material hardness is 35~55HD, which can change the profile by 2±1mm under one atmosphere pressure. The interface layer is made of polytetrafluoroethylene film pasted on the surface of the elastic layer to provide a low surface energy interface.

[0032] Further, the support layer, the elastic layer and the interface layer in the embodiment are a multi-layer heterostructure in the implementation scheme. In fact, some special functional materials, such as fluororubber and other special rubbers, can also play the same role. This embodiment only describes the relatively economical scheme, and the support layer, the elastic layer and the interface layer can also be combined in pairs. The key is to set the functional layers in the corresponding structure of the mold to eliminate the corresponding stress concentration problem and control defects.

[0033] The glass steel layer of the mold is formed by a split perfusion process, so that the edge anti-layering structure is integrally formed with the mold body. It should be noted that: a) First perfusion forming: place the corresponding four layers of 30gsmd surface felt and two layers of corresponding BX400 biaxial fibers along the surface of the model, and place the release cloth on the surface as a whole.

[0034] b) Second perfusion forming: feature identification / label and all structure layers under the heating system, place the elastic layer and the support layer in the corresponding groove position of the front edge in turn, and according to the mold structure design, lay the corresponding layers of biaxial, triaxial, quadraxial and other fiberglass cloth layers. After the laying is completed, the front and rear edge profiles are checked for vacuum extraction, and it is confirmed that there is no convexity, and the project deviation is <±1mm, which is considered to be qualified. Lay other functional layers and place the perfusion layout, start the perfusion system and perform perfusion and curing. The fiberglass / epoxy resin thickness after perfusion is 7~15mm.

[0035] c) Third perfusion forming: place the heating system according to the layout on the corresponding structure and perform perfusion forming.

[0036] d) The fourth time perfusion molding: heating the system structure layer, the supplier can use the core material according to the structure design and insulation requirements, the total thickness of the general glass fiber / epoxy resin without heating layer should be ≥15mm.

[0037] Preferably, the glass steel shell resin should consider the volume shrinkage of the matrix material, and preferably select a low volume shrinkage epoxy system of 4.5% or less. The type of glass fiber used should match the type of resin selected; after perfusion molding, the corresponding steel structure is connected to the glass steel layer and turned over; at the corresponding positions of the front and rear edges, polytetrafluoroethylene film is placed or corresponding fluorine-containing paint is sprayed.

[0038] The embodiment also provides a wind power blade manufactured by the method for preventing the wind power blade from delaminating at the edge.

[0039] The above only is the preferred embodiment of the present application, and is not used to limit the present application, although the present application is described in detail with reference to the foregoing embodiments, for those skilled in the art, the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced equivalently. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for preventing edge delamination of wind turbine blades, characterized in that, include: Based on the target profile of the wind turbine blade, the three-dimensional model of the wind turbine blade is modified. Within the preset length range of the parting line at the leading and trailing edges of the blade, the mold profile is deepened to form a groove, and transition chamfers are processed in the axial and chordal directions of the groove. An edge-protection layered structure is formed by a support layer, an elastic layer, and an interface layer; The fiberglass layer of the mold is formed by a multi-stage injection process, so that the anti-edge delamination structure is integrally formed with the mold body; In the injection process, the support layer and the elastic layer are sequentially placed in the groove, followed by the laying of fiber cloth and resin injection; after the fiberglass shell of the mold is formed, an interface layer is set in the designated area at its front and rear edges to form a low surface energy interface.

2. The method for preventing edge delamination of wind turbine blades as described in claim 1, characterized in that, The support layer is made of butyl rubber or thermoplastic elastomer with a hardness of 55HD~70HD and a thickness of 3~5mm. The surface of the support layer is mechanically polished and chemically activated.

3. The method for preventing edge delamination of wind turbine blades as described in claim 1, characterized in that, The elastic layer is made of high-density polyurethane or fluororubber, with a hardness of 35HD~55HD and a surface change of 2±1mm under one atmosphere.

4. The method for preventing edge delamination of wind turbine blades as described in claim 1, characterized in that, The interface layer is a polytetrafluoroethylene film or a fluorinated gel coat.

5. The method for preventing edge delamination of wind turbine blades as described in claim 1, characterized in that, The support layer and the elastic layer are connected by mechanical connectors or adhesives, and the interface layer is disposed on the surface of the elastic layer by means of film bonding or coating.

6. The method for preventing edge delamination of wind turbine blades as described in claim 1, characterized in that, The preset length is 0% to 25% of the length at the front and rear edge parting lines; The depth of the mold surface deepening is 3~5mm; The ratio of the transition chamfer is 1:

10.

7. The method for preventing edge delamination of wind turbine blades as described in claim 1, characterized in that, The staged infusion process includes: For the first pouring, surface felt and biaxial fiber cloth are laid on the surface of the mold, and release cloth is also laid to form the basic shape. In the second infusion, the support layer and elastic layer are placed in the groove on the already formed base surface, and then multiple layers of glass fiber cloth are laid and infused and cured to form the main shell of the mold containing the anti-edge delamination structure. The third pouring involves arranging a heating system on the main shell of the mold and then pouring the mixture. The fourth injection involves laying a structural layer on the heating system and then injecting it to form a complete mold fiberglass layer.

8. The method for preventing edge delamination of wind turbine blades as described in claim 1, characterized in that, During the mold forming process, the volume shrinkage rate of the epoxy resin system used is no more than 4.5%, and the glass fiber impregnating agent type is matched with the selected resin.

9. The method for preventing edge delamination of wind turbine blades as described in claim 1, characterized in that, After injection molding, a steel structure is connected to the fiberglass layer of the mold and the whole thing is flipped over.

10. A wind turbine blade, characterized in that, The wind turbine blade is manufactured using the method for preventing edge delamination of wind turbine blades as described in any one of claims 1 to 9.

Images