CN110789159B

CN110789159B - Forming method for wind power blade root bolt structure

Info

Publication number: CN110789159B
Application number: CN201911095304.XA
Authority: CN
Inventors: 谈源; 汤娟; 周敏杰; 邓嘉康; 王瑞
Original assignee: Changzhou Xinchuang Intelligent Technology Co Ltd
Current assignee: Changzhou Xinchuang Intelligent Technology Co Ltd
Priority date: 2019-11-11
Filing date: 2019-11-11
Publication date: 2021-04-27
Anticipated expiration: 2039-11-11
Also published as: CN110789159A

Abstract

The invention relates to the technical field of wind power blade part manufacturing, in particular to a forming method for a bolt structure at the root part of a wind power blade, which comprises the following steps: laying a fabric: laying at least one layer of fabric in a mould; setting of the underfill: placing the composite material filler in a cavity formed after the fabric is laid; the arrangement of the metal thread insert: arranging a metal thread insert of a bolt structure on the placed composite material filler; setting of top layer filler: arranging the composite material filler on the placed metal screw sleeve; closing of the fabric edge: closing the edges of the two exposed end parts of the fabric; molding: and forming the combined structure in the mold. The invention can effectively ensure the quality of the root of the blade, improve the connection reliability of the bolt sleeve and the composite material and the bearing capacity of the root bolt, and ensure the service life and the safety of the product.

Description

Forming method for wind power blade root bolt structure

Technical Field

The invention relates to the technical field of wind power blade part manufacturing, in particular to a forming method for a bolt structure at the root part of a wind power blade.

Background

Wind energy is increasingly gaining attention as a clean renewable energy source in all countries of the world. China has large wind energy storage capacity and wide distribution range, and the wind power generation industry rapidly develops to become one of the main markets of wind power generation in the whole world after Europe, America and India.

The comprehensive research and development trend analysis of the market current situation of the Chinese wind power blade in 2019-2025 released by the Chinese industry research network considers that the fan blade is a key core wind turbine component of the wind energy technical progress, and the good design, reliable quality and superior performance of the fan blade are determining factors for ensuring the normal and stable operation of a unit. The development of the Chinese fan blade industry is developed along with the development of the wind power industry and the wind power equipment industry, the Chinese fan blade is started later, the market demand is met by mainly relying on import initially, and the supply capacity of the Chinese fan blade industry is rapidly improved along with the combined efforts of domestic enterprises and scientific research institutions.

Wind-powered electricity generation blade root plays crucial effect to whole wind-powered electricity generation blade subassembly's normal operating as the main position of connection, and the quality problem of current blade root bolted construction junction has seriously influenced the life of product.

In view of the above problems, the inventor of the present invention has actively studied and innovated based on the practical experience and professional knowledge that are abundant for many years in engineering application of such products, and together with the application of the theory, in order to create a forming method for a bolt structure at the root of a wind turbine blade, so that the method has higher practicability.

Disclosure of Invention

The invention provides a forming method for a bolt structure at the root part of a wind power blade, which can effectively ensure the quality of the root part of the blade, improve the connection reliability of a bolt sleeve and a composite material and the bearing capacity of a root bolt, and ensure the service life and the safety of a product.

In order to achieve the purpose, the invention adopts the technical scheme that: the method comprises the following steps:

a forming method for a bolt structure at the root part of a wind power blade comprises the following steps,

laying a fabric: laying at least one layer of fabric in a mold, wherein the edges of two end parts of the fabric are exposed outside the mold;

setting of the underfill: placing composite material filler in a cavity formed after the fabric is laid;

the arrangement of the metal thread insert: arranging a metal thread insert of a bolt structure on the placed composite material filler;

setting of top layer filler: arranging a composite material filler on the placed metal screw sleeve, wherein a prismatic structure with a rectangular cross section is obtained by wrapping the metal screw sleeve by the bottom-layer filler and the top-layer filler;

closing of the fabric edge: closing the edges of the two exposed end parts of the fabric, so as to circumferentially coat the prism structure;

molding: and forming the combined structure in the mold.

Further, when the fabric laid in the mold is larger than one layer, the seams among the fabrics are arranged in a staggered mode.

Further, there is an overlap at the seam of each fabric layer.

Further, the fabric is at least partially pre-shaped to conform to the shape of the inner wall of the forming cavity within the mold prior to being laid within the mold.

Further, the prism structure is a regular quadrangular prism structure.

Further, the composite material filler comprises an 1/4 cylindrical surface attached to the outer portion of the metal thread insert and two planes respectively connected with two ends of the cylindrical surface, and the two planes form a right-angle structure after being connected.

Further, the composite filler is a composite preformed body, and the molding matrix is fiber or fiber fabric.

Further, the exterior of the forming matrix is also coated with fiber fabric.

Further, the material of the composite material filler and the fabric is selected from one or more of glass fiber, carbon fiber, basalt fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, polyamide fiber, polyphenylene sulfide fiber, polyimide fiber, polyester fiber, polypropylene fiber or nylon fiber.

Further, the forming process is an RTM process, an HP-RTM process or a VARI process. .

Through the technical scheme, the invention has the beneficial effects that:

according to the invention, the bolt structure for the wind power blade is molded in the above manner, so that on one hand, the difficulty in the molding process can be reduced, the dimensional stability and precision after final molding can be ensured, a stable bolt structure form can be formed, the use strength of the bolt structure is ensured through the combination form of the composite material structure and the metal structure, the rotation condition in the wind power blade is avoided through the external prism structure, and the complete root form of the wind power blade can be formed through the parallel arrangement of a plurality of bolt structures.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a flow chart of a method for forming a wind turbine blade root bolt structure;

FIG. 2 is a schematic view of the fabric being laid in the mold in step S1;

FIG. 3 is a schematic diagram of the composite filler being placed in the cavity in step S2;

FIG. 4 is a schematic diagram of the metal insert being placed on the composite filler in step S3;

FIG. 5 is a schematic view of the composite filler being placed on the metal insert in step S4;

FIG. 6 is a schematic view of the fabric after the two end edges are closed in step S5;

FIGS. 7 and 8 are schematic views of two fabric seams;

FIG. 9 is an enlarged view of a portion of FIG. 2 at A;

FIG. 10 is a schematic view of laying down a fabric after only partial preforming;

FIG. 11 is a schematic representation of a fabric after being integrally preformed;

fig. 12 and 13 are schematic views of a prism structure of a regular quadrangular prism;

FIG. 14 is a schematic view of a prism structure that is a non-regular quadrangular prism;

FIGS. 15 and 16 are schematic diagrams of an optimization of the composite filler;

FIG. 17 is a schematic illustration of a composite preform with the shaped matrix being fibers;

FIG. 18 is a schematic representation of the forming matrix of the composite preform being a ribbon fiber fabric;

FIG. 19 is a schematic illustration of a composite preform with the shaped matrix being a laid-up stack of sheet-like fiber fabrics;

FIGS. 20 to 22 are schematic diagrams illustrating that the composite material preform in FIG. 17' 19 is coated by a fiber fabric layer;

FIG. 23 is a schematic of a 3D weave of a composite preform;

reference numerals: fabric 1, edge 11, cavity 12, gap 13, overlap 14, mold 2, composite filler 3,

composite part

31, 1/4 cylindrical surface 32, flat surface 33, fiber fabric layer 34, metal thread insert 4.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like are based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. This embodiment is written in a progressive manner.

A forming method for a bolt structure at the root part of a wind power blade is shown in figure 1 and comprises the following steps,

s1, laying of a fabric 1: as shown in fig. 2, at least one layer of fabric 1 is laid in the mold 2, and the edges 11 of the two ends of the fabric 1 are exposed outside the mold 2, wherein the figure shows a specific form of arranging two layers of fabric 1, but in the present invention, the number of layers such as 3 layers, 4 layers, 5 layers and other fabrics is also within the protection range; after the fabric 1 is attached to the mold 2, a cavity 12 adaptive to the inner wall of the mold 1 is formed, and the exposed edge 11 is used for connection;

s2, setting of bottom layer fillers: placing the composite material filler 3 in a cavity 12 formed after the laying of the fabric 1, as shown in fig. 3, ensuring the placing adhesiveness, and ensuring the subsequent forming effect through better adhesion;

s3, setting of the metal thread insert 4: as shown in fig. 4, the metal thread insert 4 with a bolt structure is arranged on the placed composite material filler 3, and supported by the composite material filler 3;

s4 setting of top-level filler: as shown in fig. 5, the composite filler 3 is disposed on the metal insert 4 which is completely placed, wherein the metal insert 4 is wrapped by the bottom filler and the top filler to obtain a prismatic structure with a rectangular cross section;

s5 closure of the fabric edges: as shown in fig. 6, the edges of the two exposed ends of the fabric 1 are closed, so as to circumferentially coat the prism structure;

s6 forming: and forming the combined structure in the mold, wherein the combined structure refers to the fabric 1 and the structure combination covered in the fabric.

Preferably, in the above embodiment, when the fabric laid in the mold is more than one layer, the seams between the fabrics are arranged in a staggered manner, so as to avoid local weak points on the bolt structure, thereby improving the overall strength of the bolt structure, and the two dislocation forms shown in figures 7 and 8 can achieve the technical purpose of the invention, the seam 13 is present at the interface of the edges 11 of the fabric in figure 7, where the seam portion, after subsequent shaping, inevitably forms a local structural weakness, which results in an impaired structural life, it is preferred that there be an overlap 14 at the seam of each layer of fabric, as shown in figure 8, by which arrangement, each layer of fabric forms a complete closed structure, thereby guaranteed the integrality and the stability of inside cladding structure, can increase the bulk strength of the bolt structure after final shaping to a certain extent.

Since the web has a certain flexibility, it is inevitable that the web 1 is bent during the laying process in step S1 to affect the final molding effect, and therefore, in order to solve the above problem, at least the web 1 and the inner wall shape of the molding cavity in the mold 2 are partially preformed before being laid in the mold 2. As shown in fig. 9, the partially adaptive pre-forming at least includes the bending portion (i.e. the right angle portion) shown in the figure, because the effect of integrally forming the bolt structure and the wind turbine blade root portion is affected here, and after the partially pre-forming, as shown in fig. 10, the edge 11 can be flexibly lapped on the mold 2 for subsequent closing. Of course, in this preferred embodiment, there is also the case of an integral preforming of the fabric 1, as shown in fig. 11, which, after the integral preforming, forms only the open end of the cavity 12, so that the composite filler 3 and the metal insert 4 enter. Among them, the preforming in the present preferred embodiment may be achieved by a resin.

The prism structure formed in step S4 may be a regular quadrangular prism as shown in fig. 12 and 13, or a non-regular quadrangular prism as shown in fig. 14, and all of them may be installed by being disposed in the root structure of the wind turbine blade, but in the use process, in the case of satisfying the size requirement of the metal insert 4, the external profile size of the bolt structure is reduced as much as possible to improve the root strength, so the regular quadrangular prism structure is preferred. Wherein the top and bottom composite fillers 3 may be of one-piece construction, such as the U-shaped structure shown in fig. 13, to coat the metal insert 4, or, as shown in fig. 14, the top and bottom composite fillers 3 may be of two-piece construction 31 to coat the metal insert 4 by butt-fitting to form a U-shaped structure, preferably, as shown in fig. 15, the composite filler 3 includes 1/4 cylindrical surface 32 that conforms to the exterior of the metal insert, and two planes 33 respectively connected to both ends of the cylindrical surface, the two planes forming a right-angled structure after being connected, the structure being the combined portion 31, the entire outer surface of the metal insert 4 can be completely covered by the four assembly portions 31, which further reduces the outer dimensions of the screw construction.

Preferably, in the above embodiment, the composite filler 3 is a composite preform, and the molding base is a fiber or a fiber fabric. As shown in fig. 17, a case where the molding base is made of fiber is shown, specifically, fiber tows can be arranged in parallel along the axial direction of the metal thread insert 4 to perform with resin, so as to form a relatively stable filler structure, and ensure the structural stability after the filler structure is placed in the cavity 12, which can also be obtained by a fiber 3D weaving manner, while fig. 18 shows a case where the molding base is a ribbon fiber fabric, which can meet the use requirement by a proper distribution form, fig. 19 shows a case where the molding base is a sheet fiber fabric, and the technical purpose of the preferred embodiment can also be achieved by a laying and stacking manner, where the molding is also achieved by resin, and the molded preform still has room for deformation in the subsequent molding process. In order to ensure the structural stability of the composite material filler 3, the exterior of the molding substrate is further covered with a fiber fabric layer 34, as shown in fig. 20 to 22.

As shown in fig. 23, in the 3D weaving process of the fiber, a core material is required, the core material may be selected from a foam structure, a composite material pultrusion structure, and the like to support the fabric, and the woven fabric covers the surface of the core material.

In the present invention, the material of the composite material filler 3 and the fabric 1 is selected from one or more of glass fiber, carbon fiber, basalt fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, polyamide fiber, polyphenylene sulfide fiber, polyimide fiber, polyester fiber, polypropylene fiber, or nylon fiber. Including in particular the material selection of the above-mentioned fibres, the fibre fabric layer 34 and the fabric 1.

The molding process in step S6 is an RTM process, an HP-RTM process or a VARI process, which can achieve the above purpose, and of course, other processes for achieving the molding purpose are also within the scope of the present invention.

It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The forming method for the bolt structure at the root part of the wind power blade is characterized by comprising the following steps,

molding: forming the combined structure in the mold;

prior to laying the fabric in the mould, at least partially conforming pre-forming the fabric to the shape of the inner wall of the forming cavity in the mould;

the composite filler is a composite preformed body, and the forming matrix is fiber or fiber fabric.

2. The molding method for the wind power blade root bolt structure according to claim 1, wherein when the fabric laid in the mold is more than one layer, the seams between the fabrics are arranged in a staggered manner.

3. The forming method for the wind power blade root bolt structure according to claim 1 or 2, wherein there is an overlapping portion at the seam of each layer of fabric.

4. The molding method for the wind power blade root bolt structure according to claim 1, wherein the prism structure is a regular quadrangular prism structure.

5. The forming method for the wind power blade root bolt structure according to claim 4, wherein the composite material filler comprises 1/4 cylindrical surfaces attached to the outside of the metal thread insert and two planes respectively connected with two ends of the cylindrical surfaces, and the two planes form a right-angle structure after being connected.

6. The forming method for the wind power blade root bolt structure according to claim 1, wherein the exterior of the forming matrix is further coated with a fiber fabric.

7. The forming method for the wind power blade root bolt structure according to claim 1, wherein the material of the composite material filler and fabric is selected from one or more of glass fiber, carbon fiber, basalt fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, polyamide fiber, polyphenylene sulfide fiber, polyimide fiber, polyester fiber, polypropylene fiber or nylon fiber.

8. The forming method for the wind power blade root bolt structure according to claim 1, wherein the forming process is an RTM process, an HP-RTM process or a VARI process.