Wind power yaw brake pad and preparation method thereof

Abstract

The invention provides a wind power yaw brake pad and a preparation method thereof, and relates to the technical field of wind power generation brake systems. The wind power yaw brake pad is improved from the two aspects of structure and composition, a mechanical anchoring interface is formed through integral forming and fiber interpenetration, which is the core for realizing ultrahigh compressive strength, bending strength, shearing strength and overall structural stability, and meanwhile, noise is effectively inhibited. The proper ratio of high-strength fibers including basalt fibers and glass fibers, noise-reducing functional fibers including sepiolite fibers, light weight-reducing filler coke powder, hardening compression-resistant rigid filler corundum powder, noise-reducing lubricating functional filler mica and diatomite, and bonding heat-resistant high-performance resin phenolic aldehyde is controlled; therefore, the wind power yaw brake pad can simultaneously meet the strict requirements of light weight, low noise, high friction coefficient, high compression / bending / shearing strength and excellent corrosion resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation brake systems, and in particular to a wind power yaw brake pad and a preparation method thereof. Background Art

[0002] In recent years, wind power, as a clean and efficient form of energy, has gradually become a key component of energy structure adjustments in various countries. With technological advancements and growing environmental awareness, the wind power industry is experiencing rapid growth. The yaw brake system, a key component of wind turbines, has a direct impact on its efficiency and safety.

[0003] Currently, wind turbine yaw brake pads are primarily manufactured from a composite of friction material and a cast iron backing plate. This traditional design presents numerous challenges: First, the high density of the cast iron backing plate increases the mass of the wind turbine, consuming significant energy during braking. Second, the low coefficient of friction between the metal-based brake pad and the brake disc requires a high braking force to achieve effective braking, placing an increased burden on the braking system. Furthermore, the cast iron backing plate is susceptible to corrosion and generates noise and vibration during braking, adversely affecting the wind turbine foundation and the surrounding environment.

[0004] In order to solve the above problems, the industry has been looking for new materials and structural designs. However, existing improvement schemes have not been able to completely overcome the defects of traditional designs. For example, the offshore wind turbine yaw brake pad disclosed in patent document CN116218133A, although it has reduced weight and improved the friction coefficient to a certain extent, still has problems such as insufficient compressive strength and flexural strength, and insufficient bonding force between the lining and the friction material. Therefore, the development of a new type of wind turbine yaw brake pad that can effectively reduce friction noise and reduce the weight of wind turbine yaw brake pads, and has good mechanical properties and corrosion resistance has become the focus and difficulty of current research. Summary of the Invention

[0005] In response to the deficiencies in the prior art, the present invention provides a wind turbine yaw brake pad and a preparation method thereof. The wind turbine yaw brake pad not only has light weight, low friction noise and high friction coefficient, but also has very high compressive strength, high bending strength, high shear strength and excellent corrosion resistance.

[0006] The specific technical solutions of the present invention are: In a first aspect, the present invention provides a wind power yaw brake pad, comprising a friction body, a resin fiber reinforced backplate and a bonding layer located between the friction body and the resin fiber reinforced backplate, wherein the friction body, the bonding layer and the resin fiber reinforced backplate are integrally formed, and the raw material composition of the resin fiber reinforced backplate includes the following components in percentage by mass: 2wt.%-15wt.% of basalt fiber, 15wt.%-30wt.% of glass fiber, 5wt.%-15wt.% of sepiolite fiber, 10wt.%-30wt.% of coke powder, 3wt.%-10wt.% of corundum powder, 3wt.%-10wt.% of mica powder, 2wt.%-15wt.% of diatomaceous earth, 5wt.%-15wt.% of coarse coke powder and 10wt.%-20wt.% of phenolic resin, and some fibers in the resin fiber reinforced backplate pass through the bonding layer and are inserted into the interior of the friction body.

[0007] Furthermore, the raw material composition of the friction body includes the following components in mass percentage: 1wt.%-4wt.% of aramid fiber, 1wt.%-4wt.% of basalt fiber, 2wt.%-5wt.% of aluminum silicate fiber, 8wt.%-15wt.% of phenolic resin, 2wt.%-5wt.% of nitrile rubber powder, 2wt.%-6wt.% of flake graphite, 2wt.%-6wt.% of molybdenum disulfide, 3wt.%-10wt.% of mica powder, 1wt.%-5wt.% of bauxite, 20wt.%-30wt.% of petroleum coke, 15wt.%-25wt.% of potassium feldspar powder, 3wt.%-8wt.% of expanded vermiculite powder and 3wt.-8wt.% of calcium carbonate powder.

[0008] Furthermore, the raw material composition of the bonding layer includes the following components in percentage by mass: 85wt.%-98wt.% of phenolic resin and 2wt.%-15wt.% of chopped carbon fibers.

[0009] Furthermore, the thickness ratio of the friction body, the bonding layer and the resin fiber reinforcement back plate is (6-8):(0.1-0.2):(8-10).

[0010] Furthermore, the basalt fiber and the sepiolite fiber are of equal length, which is 3-5 mm.

[0011] Furthermore, the compressive strength of the resin fiber reinforced backboard is 178-188 MPa and the flexural strength is 44-50 MPa.

[0012] Furthermore, the shear strength between the friction body and the resin fiber reinforced back plate is 17-20 MPa.

[0013] In a second aspect, the present invention provides a method for preparing the above-mentioned wind turbine yaw brake pad, comprising the following steps: S1. 2 wt.%-15 wt.% of basalt fibers and 5 wt.%-15 wt.% of sepiolite fibers, accounting for 2 wt.%-15 wt.% of the total mass of the resin fiber reinforced backsheet, are premixed and entangled with each other to form a prefabricated fiber body; S2, the prefabricated fiber body described in step S1 and 10wt.%-30wt.% of coke powder, 3wt.%-10wt.% of corundum powder, 3wt.%-10wt.% of mica powder, 2wt.%-15wt.% of diatomaceous earth, 5wt.%-15wt.% of coarse coke powder and 10wt.%-20wt.% of phenolic resin, which account for the total mass of the resin fiber reinforced backboard, are stirred and mixed uniformly for the first time, and then 15wt.%-25wt.% of glass fiber is added and stirred and mixed for the second time to obtain a backboard material; S3, the friction body material, the bonding layer material and the back plate material described in step S2 are sequentially added to a hot pressing machine and subjected to integrated hot pressing. During the integrated hot pressing process, some fibers in the back plate material pass through the bonding layer material and are inserted into the interior of the friction body material. The mass ratio of the friction body material, the bonding layer material and the back plate material is (80-100):(1-2):(80-100). The integrated hot pressing temperature is 140-170° C. and the pressure is 200-500 KGF. The brake pad preform is further cured to obtain the brake pad preform. S4. The brake pad prefabricated part is mechanically processed to obtain a wind turbine yaw brake pad.

[0014] Furthermore, in step S2, the stirring speed of the first stirring is ≥1500 r / min and the time is ≥10 min, and the speed of the second stirring is 600-900 r / min and the time is ≥5 min.

[0015] Furthermore, the curing treatment in step S3 is performed at a temperature of 170-200° C. and for a time of 15-20 h.

[0016] The positive progress effect of the present invention is: The wind turbine yaw brake pad provided by this invention features improvements in both structure and composition. Through integrated molding and fiber interpenetration, a mechanical anchoring interface is formed, which is the key to achieving ultra-high shear strength, flexural strength, and overall structural stability, while also effectively suppressing noise. Furthermore, a carefully selected combination of high-strength fibers (basalt and glass), functional fibers (sepiolite for noise reduction), lightweight fillers (coke powder for weight reduction), rigid fillers (corundum powder for hardening and compressive resistance), functional fillers (mica for stabilization and lubrication, diatomaceous earth for noise reduction), and high-performance resins (phenolic for bonding and heat resistance) ensures that the wind turbine yaw brake pad simultaneously meets the stringent requirements of lightweight, low noise, high coefficient of friction, high compressive, flexural, and shear strength, and excellent corrosion resistance. This makes it ideal for use in wind turbine yaw brake systems, where harsh environments, complex forces, and extremely high reliability requirements are demanded. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a graph showing the compressive strength test results of the resin fiber reinforced backplate in the wind turbine yaw brake pad prepared in Example 1.

[0018] Figure 2 This is a graph showing the bending strength test results of the resin fiber reinforced back plate in the wind turbine yaw brake pad prepared in Example 1.

[0019] Figure 3 This is a graph showing the bending strength test results of the resin fiber reinforced backplate in the wind turbine yaw brake pad prepared in Example 2.

[0020] Figure 4 This is a graph showing the bending strength test results of the resin fiber reinforced back plate in the wind turbine yaw brake pad prepared in Example 3. DETAILED DESCRIPTION

[0021] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, specific embodiments of the present invention are described in detail below. It should be noted that the following embodiments are only intended to illustrate the implementation methods and typical parameters of the present invention, and are not intended to limit the parameter ranges described in the present invention. Reasonable variations derived therefrom are still within the scope of protection of the claims of the present invention.

[0022] It should be noted that the endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed herein.

[0023] Unless otherwise defined, all terms, symbols and other scientific terms used herein are intended to have the same meaning as commonly understood by those skilled in the art to which the present invention belongs. In some cases, terms with conventional meanings are defined herein for the purpose of clarification or ease of reference, and such definitions herein should not be construed as indicating significant differences from conventional understandings in the art. The technical methods described or cited herein are generally well understood by those skilled in the art and are adopted by conventional methods. Unless otherwise stated, the use of commercially available kits, reagents and instruments was carried out in accordance with the protocols and parameters given by the manufacturers.

[0024] The specific technical solutions of the present invention are: In a first aspect, the present invention provides a wind power yaw brake pad, comprising a friction body, a resin fiber reinforced backplate and a bonding layer located between the friction body and the resin fiber reinforced backplate, wherein the friction body, the bonding layer and the resin fiber reinforced backplate are integrally formed, and the raw material composition of the resin fiber reinforced backplate includes the following components in percentage by mass: 2wt.%-15wt.% of basalt fiber, 15wt.%-30wt.% of glass fiber, 5wt.%-15wt.% of sepiolite fiber, 10wt.%-30wt.% of coke powder, 3wt.%-10wt.% of corundum powder, 3wt.%-10wt.% of mica powder, 2wt.%-15wt.% of diatomaceous earth, 5wt.%-15wt.% of coarse coke powder and 10wt.%-20wt.% of phenolic resin, and some fibers in the resin fiber reinforced backplate pass through the bonding layer and are inserted into the interior of the friction material.

[0025] The present invention provides a wind turbine yaw brake pad, in which the resin fiber reinforced back plate and the friction body are not simply bonded together, but are integrally formed during the manufacturing process, and some fibers (basalt fiber, glass fiber, sepiolite fiber) in the resin fiber reinforced back plate pass through the middle bonding layer and are directly inserted into the friction body, so that a mechanical anchoring structure is formed between the resin fiber reinforced back plate and the friction body. When shear stress exists between the layers, these fibers mainly rely on their own tensile strength to resist the stress, rather than simply relying on the bonding force of the bonding layer; the phenolic resin matrix and the middle bonding layer provide chemical bonding, which works together with the mechanical anchoring of the fibers to form an extremely strong interface, which can effectively transmit the huge shear force generated by braking, significantly improve the bonding strength between the resin fiber reinforced back plate and the friction body, and thus significantly improve the shear strength of the wind turbine yaw brake pad. Basalt and glass fibers are continuous or long within the plane of the backplate, providing the primary resistance to bending loads. The fibers' high strength and modulus translate directly into high bending strength and stiffness. Inserted into the friction element, the fibers act as countless "reinforcements" at the interface between the backplate and friction element, significantly enhancing this area's resistance to bending stresses and preventing buckling or cracking under braking or installation stresses. The integrated design eliminates the potential weak link of conventional adhesive bonds, allowing the entire brake pad to withstand forces as a single unit during bending, resulting in greater strength. Basalt and glass fibers, with their extremely high tensile strength and modulus, serve as the primary load-bearing framework, directly absorbing the significant normal pressure applied during braking. Corundum (aluminum oxide), an extremely hard particle, is incorporated into the fiber framework and resin matrix, significantly increasing the composite's compressive modulus and compressive strength. Upon curing, the phenolic resin forms a rigid network that firmly bonds the fibers and filler, resisting compression deformation. Mineral fillers such as corundum and / or mica also contribute to increased stiffness and packing density. The coordinated combination of the composition and structure of the wind turbine yaw brake pads enables the wind turbine yaw brake pads to have ultra-high compressive strength, bending strength and shear strength.

[0026] The raw material composition of the back plate is mainly basalt fiber, glass fiber, phenolic resin and coke powder and coarse coke powder with relatively low density, which is far lower than that of the traditional steel back plate, thereby effectively reducing the weight of the wind power yaw brake pad and realizing light weight; in the raw material composition of the back plate, the sepiolite fiber and basalt fiber have good damping and vibration reduction performance, which helps to absorb the vibration energy generated in the braking process and prevent it from being converted into irritating noise; the mica powder has a lamellar structure and can provide certain lubrication and damping effect at the friction interface, which helps to smooth friction and reduce noise; the diatomite also helps to improve the friction stability and reduce the noise tendency, and the carbonaceous component in the coke powder helps to form a relatively stable friction film and reduce the stick-slip phenomenon (one of the main causes of noise), and the close combination of the resin fiber reinforced back plate and the friction body with the integrated and fiber interpenetrating structure makes it more difficult for vibration to occur and amplify at the interface, thereby reducing the generation of noise, so that the structure of the friction body and the back plate and the mutual coordination between the raw material components in the back plate realize the low noise performance of the wind power yaw brake pad from the aspects of wear reduction, vibration reduction and noise absorption.

[0027] The wind power yaw brake pad provided by the application is improved from the aspects of structure and composition, and the mechanical anchoring interface is formed through integrated molding and fiber interpenetration, which is the core of realizing ultrahigh shear strength, bending strength and overall structural stability, and effectively inhibits noise. And combined with the appropriate matching of high-strength fibers (basalt, glass), functional fibers (sepiolite noise reduction), light fillers (coke powder weight reduction), rigid fillers (corundum powder hardening and pressure resistance), functional fillers (mica stable lubrication, diatomite noise reduction) and high-performance resin (phenolic bonding and heat resistance), the wind power yaw brake pad can meet the strict requirements of light weight, low noise, high friction coefficient, high pressure resistance / bending resistance / shear strength and excellent corrosion resistance, and is very suitable for application in the yaw brake system of the wind turbine generator set which has harsh environment, complex stress and high reliability requirements.

[0028] Furthermore, the raw material composition of the friction body includes the following components in mass percentage: 1wt.%-4wt.% of aramid fiber, 1wt.%-4wt.% of basalt fiber, 2wt.%-5wt.% of aluminum silicate fiber, 8wt.%-15wt.% of phenolic resin, 2wt.%-5wt.% of nitrile rubber powder, 2wt.%-6wt.% of flake graphite, 2wt.%-6wt.% of molybdenum disulfide, 3wt.%-10wt.% of mica powder, 1wt.%-5wt.% of bauxite, 20wt.%-30wt.% of petroleum coke, 15wt.%-25wt.% of potassium feldspar powder, 3wt.%-8wt.% of expanded vermiculite powder and 3wt.-8wt.% of calcium carbonate powder. When the raw materials of the friction body are composed of the above components, the components of the friction body can be perfectly matched with the resin fiber reinforced backing plate, and the fibers in the friction body (aramid, basalt, aluminum silicate) can also be interwoven with the fibers coming from the backing plate, further enhancing the mechanical interlocking strength, improving the interlayer bonding force (shear resistance) and integrity (bending resistance). At the same time, since the raw materials in the friction body and the raw materials of the resin fiber reinforced backing plate contain many of the same components, it is helpful to adjust the thermal expansion coefficient of the friction body and the resin-based backing plate, thereby reducing thermal stress.

[0029] Furthermore, the raw material composition of the bonding layer includes the following components in mass percentage: 85wt.%-98wt.% of phenolic resin and 2wt.%-15wt.% of chopped carbon fibers. The resin proportion in the raw materials of the bonding layer is limited to 85wt.%-98wt.%, ensuring the formation of a dense and continuous bonding film. The high reactivity of the phenolic resin causes chemical cross-linking with the backboard (containing a phenolic matrix) and the friction body (containing a phenolic resin) during curing, achieving molecular-level bonding rather than simple physical adhesion. The proportion of chopped carbon fibers in the raw materials of the bonding layer is limited to 2wt.%-15wt.%, which allows the chopped carbon fibers to be randomly distributed in the bonding layer, forming a three-dimensional network, which can significantly improve the toughness between layers.

[0030] Furthermore, the thickness ratio of the friction body, adhesive layer, and resin fiber reinforced backing plate is (6-8):(0.1-0.2):(8-10). By limiting the thickness ratio of the friction body, adhesive layer, and resin fiber reinforced backing plate to (6-8):(0.1-0.2):(8-10), a thicker backing plate can form a high-strength skeleton. The moderate thickness of the friction body ensures excellent friction performance while also taking into account lightweight. The extremely thin interface layer can also reduce interfacial shear stress concentration and inhibit interlaminar crack propagation while providing sufficient bonding.

[0031] Further, the basalt fibers and the sepiolite fibers in step S1 have equal length of 3-5 mm. The basalt fibers and the sepiolite fibers with equal length of 3-5 mm are more conducive to forming a uniform and consistent winding structure, and the high strength of the basalt fibers and the network structure of the sepiolite fibers are complementary to each other, thereby forming a three-dimensional support network and improving the crack resistance. Further, the resin fiber reinforced back plate has a compressive strength of 178-188 Mpa and a bending strength of 44-50 Mpa.

[0032] Further, the shear strength between the friction body and the resin fiber reinforced back plate is 17-20 Mpa.

[0033] In a second aspect, the present application provides a preparation method of the wind power yaw brake pad, comprising the following steps: S1, 2wt.%-15wt.% of basalt fibers and 5wt.%-15wt.% of sepiolite fibers in the total mass of the resin fiber reinforced back plate are premixed and then wound with each other to form a preformed fiber body; S2, the preformed fiber body in step S1 is uniformly mixed with 10wt.%-30wt.% of coke powder, 3wt.%-10wt.% of corundum powder, 3wt.%-10wt.% of mica powder, 2wt.%-15wt.% of diatomite, 5wt.%-15wt.% of coarse coke powder and 10wt.%-20wt.% of phenolic resin by first stirring, and then 15wt.%-25wt.% of glass fibers are added and mixed by second stirring to obtain a back plate material; S3, the friction body material, the adhesive layer material and the back plate material in step S2 are sequentially added into a hot press forming machine, and then integrally hot-pressed, in which part of the fibers in the back plate material penetrate through the adhesive layer material and insert into the inside of the friction body material, the mass ratio of the friction body material, the adhesive layer material and the back plate material is (80-100):(1-2):(80-100), the temperature of the integrally hot-pressing is 140-170℃, the pressure is 200-500 KGF, and then the brake pad preform is obtained after further curing treatment; S4, the brake pad preform is machined to obtain the wind power yaw brake pad.

[0034] The preparation method of the wind power yaw brake pad provided by the present invention is to first pre-mix basalt fiber and sepiolite fiber, and the two fibers are entangled with each other after pre-mixing. Adding them as raw materials to the backboard material is beneficial to improving the bending strength, compressive strength and shear strength of the backboard. Then, the mixing is carried out in a step-by-step mixing manner to obtain a backboard material with uniform mixing and complete fiber structure. Further, the friction body material, the bonding layer material and the backboard material are integrally formed and pressed. During the integral forming and pressing process, part of the fibers in the backboard material are inserted into the interior of the friction body material. In combination with controlling the pressing temperature and pressing pressure, an integrally formed wind power yaw brake pad with a mechanical anchoring structure is formed.

[0035] Furthermore, in step S2, the first stirring is performed at a speed of ≥1500 r / min and for ≥10 min, and the second stirring is performed at a speed of 600-900 r / min and for ≥5 min. By performing the two mixing steps, the raw materials other than the glass fiber are thoroughly mixed during the first high-speed mixing step, while the low-speed stirring of the mixture after the glass fiber is added prevents damage to the glass fiber.

[0036] Furthermore, the curing treatment in step S3 is performed at a temperature of 170-200° C. and for a time of 15-20 h.

[0037] The technical solutions of the present invention are further illustrated below with reference to specific examples and comparative examples. All reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further treatment. The instruments used in the examples are commercially available.

[0038] Example 1

[0039] This embodiment provides a wind turbine yaw brake pad, comprising a friction body, an adhesive layer, and a resin fiber reinforced back plate integrally formed with the friction material, which are arranged in sequence. The pad is manufactured by the following steps: D1: Weigh the raw materials for the friction body: 4 wt.% aramid fiber, 1 wt.% basalt fiber, 5 wt.% aluminum silicate fiber, 8 wt.% phenolic resin, 5 wt.% nitrile rubber powder, 2 wt.% flake graphite, 6 wt.% molybdenum disulfide, 3 wt.% mica powder, 5 wt.% bauxite, 20 wt.% petroleum coke, 25 wt.% potassium feldspar powder, 8 wt.% expanded vermiculite powder, and 8 wt.% calcium carbonate powder. Place the mixture in a mixer and mix at a stirring speed of 1500 r / min for 10 min to obtain the friction body material. D2: Weigh the raw materials for the bonding layer: phenolic resin and chopped carbon fibers in a mass ratio of 98:2, and mix them to obtain the bonding layer material; D3: Weigh the raw materials for the resin fiber reinforced backsheet: 10 wt.% 3 mm basalt fiber, 20 wt.% 0.3-0.5 mm glass fiber, 5 wt.% 3 mm sepiolite fiber, 15 wt.% coke powder, 5 wt.% corundum powder, 10 wt.% mica powder, 15 wt.% diatomaceous earth, 10 wt.% coarse coke powder, and 10 wt.% phenolic resin; D4, pre-mixing the basalt fiber and the sepiolite fiber in step D3, wherein the basalt fiber and the sepiolite fiber are entangled with each other during the pre-mixing process to form a prefabricated fiber body; D5. Add the prefabricated fiber body in step D4 and the coke powder, corundum powder, mica powder, diatomaceous earth, coarse coke powder, and phenolic resin in step D3 into a high-speed mixer and stir and mix them for a first time at a speed of 1500 r / min for 10 minutes. Then, add the glass fiber in step D3 and stir and mix them for a second time at a speed of 600 r / min for 5 minutes to obtain a backboard material. D6. The friction body material prepared in step D1, the bonding layer material prepared in step D2, and the backing plate material prepared in step D5 were sequentially added to a mold of a hot pressing machine for integrated hot pressing. The masses of the friction body material, the bonding layer material, and the backing plate material were 400 g, 4 g, and 400 g, respectively. The integrated hot pressing was performed at a temperature of 140° C., a pressure of 200 kgf, and a time of 800 s. After the integrated hot pressing was completed, the mold was demolded and cooled, and then the material was kept in an oven at 180° C. for 15 h to obtain a brake pad preform. D7. Polishing, grinding, slotting and marking the brake pad prefabricated in step D6 to produce a wind turbine yaw brake pad.

[0040] Example 2

[0041] This embodiment provides a wind turbine yaw brake pad, comprising a friction body, an adhesive layer, and a resin fiber reinforced back plate integrally formed with the friction material, which are arranged in sequence. The pad is manufactured by the following steps: D1: Weigh the raw materials for the friction body: 4 wt.% aramid fiber, 1 wt.% basalt fiber, 5 wt.% aluminum silicate fiber, 8 wt.% phenolic resin, 5 wt.% nitrile rubber powder, 2 wt.% flake graphite, 6 wt.% molybdenum disulfide, 3 wt.% mica powder, 5 wt.% bauxite, 20 wt.% petroleum coke, 25 wt.% potassium feldspar powder, 8 wt.% expanded vermiculite powder, and 8 wt.% calcium carbonate powder. Place the mixture in a mixer and mix at a stirring speed of 1500 r / min for 10 min to obtain the friction body material. D2: Weigh the raw materials for the bonding layer: phenolic resin and chopped carbon fibers in a mass ratio of 95:5 and mix them to obtain the bonding layer material; D3: Weigh the raw materials for the resin fiber reinforced backsheet: 10 wt.% basalt fiber, 25 wt.% glass fiber, 5 wt.% sepiolite fiber, 10 wt.% coke powder, 10 wt.% corundum powder, 10 wt.% mica powder, 10 wt.% diatomaceous earth, 10 wt.% coarse coke powder, and 10 wt.% phenolic resin; D4, pre-mixing the basalt fiber and the sepiolite fiber in step D3, wherein the basalt fiber and the sepiolite fiber are entangled with each other during the pre-mixing process to form a prefabricated fiber body; D5. Add the prefabricated fiber body in step D4 and the coke powder, corundum powder, mica powder, diatomaceous earth, coarse coke powder, and phenolic resin in step D3 into a high-speed mixer and stir and mix them for a first time at a speed of 1500 r / min for 10 minutes. Then, add the glass fiber in step D3 and stir and mix them for a second time at a speed of 600 r / min for 5 minutes to obtain a backboard material. D6. The friction body material prepared in step D1, the bonding layer material prepared in step D2, and the backing plate material prepared in step D5 were sequentially added to a mold of a hot pressing machine for integrated hot pressing. The masses of the friction body material, the bonding layer material, and the backing plate material were 400 g, 5 g, and 400 g, respectively. The integrated hot pressing was performed at a temperature of 160° C., a pressure of 300 kgf, and a time of 900 s. After the integrated hot pressing was completed, the mold was demolded and cooled, and then the material was kept in an oven at 180° C. for 20 h to obtain a brake pad preform. D7. Polishing, grinding, slotting and marking the brake pad prefabricated in step D6 to produce a wind turbine yaw brake pad.

[0042] Example 3

[0043] This embodiment provides a wind turbine yaw brake pad, comprising a friction body, an adhesive layer, and a resin fiber reinforced back plate integrally formed with the friction material, which are arranged in sequence. The pad is manufactured by the following steps: D1: Weigh the raw materials for the friction body: 4 wt.% aramid fiber, 1 wt.% basalt fiber, 5 wt.% aluminum silicate fiber, 8 wt.% phenolic resin, 5 wt.% nitrile rubber powder, 2 wt.% flake graphite, 6 wt.% molybdenum disulfide, 3 wt.% mica powder, 5 wt.% bauxite, 20 wt.% petroleum coke, 25 wt.% potassium feldspar powder, 8 wt.% expanded vermiculite powder, and 8 wt.% calcium carbonate powder. Place the mixture in a mixer and mix at a stirring speed of 1500 r / min for 10 min to obtain the friction body material. D2: Take the raw materials of the bonding layer: phenolic resin and chopped carbon fiber according to the mass ratio of 92:8, mix to get the bonding layer material; D3: Take the raw materials of the resin fiber reinforced back plate: 5wt.% basalt fiber, 30wt.% glass fiber, 5wt.% sepiolite fiber, 15wt.% coke powder, 5wt.% corundum powder, 10wt.% mica powder, 10wt.% diatomite, 10wt.% coarse coke powder and 10wt.% phenolic resin; D4, the basalt fiber and sepiolite fiber in step D3 are premixed, and the basalt fiber and sepiolite fiber are intertwined with each other during the premixing process to form a preformed fiber body; D5, the preformed fiber body in step D4 and the coke powder, corundum powder, mica powder, diatomite, coarse coke powder and phenolic resin in step D3 are added to a high-speed mixer for first stirring and mixing, the first stirring and mixing is at a speed of 1500 r / min for 10 min, then the glass fiber in step D3 is added for second stirring and mixing, the second stirring and mixing is at a speed of 600 r / min for 5 min, to obtain a back plate material; D6, the friction body material in step D1, the bonding layer material in step D2 and the back plate material in step D5 are sequentially added to the mold of a hot press forming machine for integrated hot press forming, the integrated hot press forming is at a temperature of 160 ℃, a pressure of 300KGF and a time of 900 s, the mass of the friction body material, the bonding layer material and the back plate material is 400 g, 6 g and 400 g respectively, after the integrated hot press forming, demolding and cooling are performed, then the preform is kept in an oven at 180 ℃ for 20 h, to obtain a brake disc preform; D7, the brake disc preform in step D6 is polished, ground, slotted and marked to obtain a wind power yaw brake disc.

[0044] Example 4

[0045] The embodiment provides a wind power yaw brake disc, which comprises a friction body, a bonding layer and a resin fiber reinforced back plate integrally formed with the friction material arranged in sequence, and is prepared by the following steps: D1: Take the raw materials of the friction body: 1wt.% aramid fiber, 4wt.% basalt fiber, 2wt.% aluminum silicate fiber, 15wt.% phenolic resin, 2wt.% butyronitrile rubber powder, 6wt.% flaky graphite, 2wt.% molybdenum disulfide, 10wt.% mica powder, 1wt.% bauxite, 30wt.% petroleum coke, 15wt.% potassium feldspar powder, 6wt.% expanded vermiculite powder and 6wt.% calcium carbonate powder, put them in a mixer and mix at a stirring speed of 1500 r / min for 10 min to obtain a friction body material; D2: Weigh the raw materials for the bonding layer: phenolic resin and chopped carbon fibers in a mass ratio of 90:10, and mix them to obtain the bonding layer material; D3: Weigh the raw materials for the resin fiber reinforced backsheet: 10 wt.% basalt fiber, 20 wt.% glass fiber, 5 wt.% sepiolite fiber, 10 wt.% coke powder, 10 wt.% corundum powder, 10 wt.% mica powder, 10 wt.% diatomaceous earth, 10 wt.% coarse coke powder, and 15 wt.% phenolic resin; D4, pre-mixing the basalt fiber and the sepiolite fiber in step D3, wherein the basalt fiber and the sepiolite fiber are entangled with each other during the pre-mixing process to form a prefabricated fiber body; D5. Add the prefabricated fiber body in step D4 and the coke powder, corundum powder, mica powder, diatomaceous earth, coarse coke powder, and phenolic resin in step D3 into a high-speed mixer and stir and mix them for a first time at a speed of 1500 r / min for 10 minutes. Then, add the glass fiber in step D3 and stir and mix them for a second time at a speed of 600 r / min for 5 minutes to obtain a backboard material. D6. The friction body material prepared in step D1, the bonding layer material prepared in step D2, and the backing plate material prepared in step D5 were sequentially added to a mold of a hot pressing machine for integrated hot pressing. The masses of the friction body material, the bonding layer material, and the backing plate material were 400 g, 7 g, and 400 g, respectively. The integrated hot pressing was performed at a temperature of 170° C., a pressure of 350 kgf, and a time of 800 s. After the integrated hot pressing was completed, the mold was demolded and cooled, and then the material was kept in an oven at 180° C. for 20 h to obtain a brake pad preform. D7. Polishing, grinding, slotting and marking the brake pad prefabricated in step D6 to produce a wind turbine yaw brake pad.

[0046] Example 5

[0047] This embodiment provides a wind turbine yaw brake pad, comprising a friction body, an adhesive layer, and a resin fiber reinforced back plate integrally formed with the friction material, which are arranged in sequence. The pad is manufactured by the following steps: D1: Weigh the raw materials for the friction body: 1 wt.% aramid fiber, 4 wt.% basalt fiber, 2 wt.% aluminum silicate fiber, 15 wt.% phenolic resin, 2 wt.% nitrile rubber powder, 6 wt.% flake graphite, 2 wt.% molybdenum disulfide, 10 wt.% mica powder, 1 wt.% bauxite, 30 wt.% petroleum coke, 15 wt.% potassium feldspar powder, 6 wt.% expanded vermiculite powder, and 6 wt.% calcium carbonate powder. Place the mixture in a mixer and mix at a stirring speed of 1500 r / min for 10 min to obtain the friction body material. D2: Weigh the raw materials for the bonding layer: phenolic resin and chopped carbon fibers in a mass ratio of 85:15 and mix them to obtain the bonding layer material; D3: Weigh the raw materials for the resin fiber reinforced backsheet: 15 wt.% basalt fiber, 15 wt.% glass fiber, 15 wt.% sepiolite fiber, 15 wt.% coke powder, 5 wt.% corundum powder, 5 wt.% mica powder, 5 wt.% diatomaceous earth, 10 wt.% coarse coke powder, and 15 wt.% phenolic resin; D4, pre-mixing the basalt fiber and the sepiolite fiber in step D3, wherein the basalt fiber and the sepiolite fiber are entangled with each other during the pre-mixing process to form a prefabricated fiber body; D5. Add the prefabricated fiber body in step D4 and the coke powder, corundum powder, mica powder, diatomaceous earth, coarse coke powder, and phenolic resin in step D3 into a high-speed mixer and stir and mix them for a first time at a speed of 1500 r / min for 10 minutes. Then, add the glass fiber in step D3 and stir and mix them for a second time at a speed of 600 r / min for 5 minutes to obtain a backboard material. D6. The friction body material prepared in step D1, the bonding layer material prepared in step D2, and the backing plate material prepared in step D5 were sequentially added to a mold of a hot pressing machine for integrated hot pressing. The masses of the friction body material, the bonding layer material, and the backing plate material were 400 g, 8 g, and 400 g, respectively. The integrated hot pressing was performed at a temperature of 170° C., a pressure of 400 KGF, and a time of 800 s. After the integrated hot pressing was completed, the mold was demolded and cooled, and then the material was kept in an oven at 170° C. for 15 h to obtain a brake pad preform. D7. Polishing, grinding, slotting and marking the brake pad prefabricated in step D6 to produce a wind turbine yaw brake pad.

[0048] Comparative Example 1 The wind turbine yaw brake pad provided in this comparative example is from Example 1 of patent document CN115322508A. The friction coefficient of the wind turbine yaw brake pad is 0.37, and the compressive strength is 27 MPa.

[0049] The wind turbine yaw brake pads prepared in the embodiment were characterized and tested, and the results are as follows: The performance test results of the friction bodies and backing plates of the wind turbine yaw brake pads prepared in Examples 1-5 are shown in Table 1. As can be seen from the data in the table, the flexural strength of the resin fiber reinforced backing plates of the wind turbine yaw brake pads prepared in Examples 1-5 was greater than 43 MPa, and the compressive strength was greater than 178 MPa, significantly higher than the wind turbine yaw brake pad provided in Comparative Example 1. The flexural strength and compressive strength of the resin fiber reinforced backing plates in Examples 1-5 reached a maximum of 56.9 MPa and 187.89 MPa respectively. The shear strength between the resin fiber reinforced backing plates and the friction bodies in Examples 1-5 was greater than 16 MPa, with a maximum of 19.67 MPa. The flexural strength of the friction bodies in Examples 1-5 was greater than 34 MPa, and the compressive strength was greater than 108 MPa.

[0050]

[0051] Figure 1 This figure shows the compressive strength test results of the resin fiber-reinforced backplate used in the wind turbine yaw brake pad produced in Example 1. The test specimen was 50 mm long, 10.33 mm thick, and 10.55 mm wide. The load limit P was 16494.8 N. The calculated compressive strength of the resin fiber-reinforced backplate was 179.95 MPa.

[0052] Figure 2 This figure shows the flexural strength test results of the resin fiber-reinforced backplate used in the wind turbine yaw brake pad produced in Example 1. The test specimen had a length of 50 mm, a thickness of 10.22 mm, a width of 8.47 mm, and a support span of 30 mm. The breaking load value, P, was 825.43 N. The calculated flexural strength of the resin fiber-reinforced backplate was 50.66 MPa.

[0053] Figure 3 This figure shows the flexural strength test results of the resin fiber-reinforced backplate used in the wind turbine yaw brake pad produced in Example 2. The test specimen had a length of 50 mm, a thickness of 8.33 mm, a width of 10.65 mm, and a support span of 30 mm. The breaking load value P was 1139.27 N, and the calculated flexural strength of the resin fiber-reinforced backplate was 54.46 MPa.

[0054] Figure 4 This figure shows the flexural strength test results of the resin fiber-reinforced backplate of the wind turbine yaw brake pad produced in Example 3. The test specimen had a length of 50 mm, a thickness of 11.29 mm, a width of 11.56 mm, and a support span of 30 mm. The breaking load value P was 1907.74 N, and the calculated flexural strength of the resin fiber-reinforced backplate was 56.90 MPa.

[0055] The density of the resin fiber reinforced back plate in the wind turbine yaw brake pad prepared in Example 3 is 2.01 g / cm 3 , hardness is 207 HV, and porosity is 1.08.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some or all of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wind turbine yaw brake pad, characterized in that: The invention comprises a friction body, a resin fiber reinforced back plate and a bonding layer located between the friction body and the resin fiber reinforced back plate. The friction body, the bonding layer and the resin fiber reinforced back plate are integrally formed. The raw material composition of the resin fiber reinforced back plate includes the following components in percentage by mass: 2wt.%-15wt.% of basalt fiber, 15wt.%-30wt.% of glass fiber, 5wt.%-15wt.% of sepiolite fiber, 10wt.%-30wt.% of coke powder, 3wt.%-10wt.% of corundum powder, 3wt.%-10wt.% of mica powder, 2wt.%-15wt.% of diatomaceous earth, 5wt.%-15wt.% of coarse coke powder and 10wt.%-20wt.% of phenolic resin. Some fibers in the resin fiber reinforced back plate pass through the bonding layer and are inserted into the interior of the friction body.

2. The wind turbine yaw brake pad according to claim 1, characterized in that: The raw materials of the friction body include the following components in mass percentage: 1wt.%-4wt.% of aramid fiber, 1wt.%-4wt.% of basalt fiber, 2wt.%-5wt.% of aluminum silicate fiber, 8wt.%-15wt.% of phenolic resin, 2wt.%-5wt.% of nitrile rubber powder, 2wt.%-6wt.% of flake graphite, 2wt.%-6wt.% of molybdenum disulfide, 3wt.%-10wt.% of mica powder, 1wt.%-5wt.% of bauxite, 20wt.%-30wt.% of petroleum coke, 15wt.%-25wt.% of potassium feldspar powder, 3wt.%-8wt.% of expanded vermiculite powder and 3wt.-8wt.% of calcium carbonate powder.

3. The wind turbine yaw brake pad according to claim 1, characterized in that: The raw material composition of the bonding layer includes the following components in percentage by mass: 85wt.%-98wt.% of phenolic resin and 2wt.%-15wt.% of chopped carbon fibers.

4. The wind turbine yaw brake pad according to claim 1, characterized in that: The thickness ratio of the friction body, the bonding layer and the resin fiber reinforcement back plate is (6-8):(0.01-0.2):(8-10).

5. The wind turbine yaw brake pad according to claim 1, characterized in that: The basalt fiber and the sepiolite fiber have the same length, which is 3-5 mm.

6. The wind turbine yaw brake pad according to claim 1, characterized in that: The compressive strength of the resin fiber reinforced backboard is 178-188 MPa and the flexural strength is 44-50 MPa.

7. The wind turbine yaw brake pad according to claim 1, characterized in that: The shear strength between the friction body and the resin fiber reinforced back plate is 17-20 MPa.

8. A method for preparing a wind turbine yaw brake pad according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. 2 wt.%-15 wt.% of basalt fibers and 5 wt.%-15 wt.% of sepiolite fibers, accounting for 2 wt.%-15 wt.% of the total mass of the resin fiber reinforced backsheet, are premixed and entangled with each other to form a prefabricated fiber body; S2, the prefabricated fiber body described in step S1 and 10wt.%-30wt.% of coke powder, 3wt.%-10wt.% of corundum powder, 3wt.%-10wt.% of mica powder, 2wt.%-15wt.% of diatomaceous earth, 5wt.%-15wt.% of coarse coke powder and 10wt.%-20wt.% of phenolic resin, which account for the total mass of the resin fiber reinforced backboard, are stirred and mixed uniformly for the first time, and then 15wt.%-25wt.% of glass fiber is added and stirred and mixed for the second time to obtain a backboard material; S3, the friction body material, the bonding layer material and the back plate material described in step S2 are sequentially added to a hot pressing machine and subjected to integrated hot pressing. During the integrated hot pressing process, some fibers in the back plate material pass through the bonding layer material and are inserted into the interior of the friction body material. The mass ratio of the friction body material, the bonding layer material and the back plate material is (80-100):(1-2):(80-100). The integrated hot pressing temperature is 140-170° C. and the pressure is 200-500 KGF. The brake pad preform is further cured to obtain the brake pad preform. S4. The brake pad prefabricated part is mechanically processed to obtain a wind turbine yaw brake pad.

9. The method for preparing a wind turbine yaw brake pad according to claim 8, characterized in that: The stirring speed of the first stirring in step S2 is ≥1500 r / min and the time is ≥10 min, and the speed of the second stirring is 600-900 r / min and the time is ≥5 min.

10. The method for preparing a wind turbine yaw brake pad according to claim 8, characterized in that: The curing treatment in step S3 is performed at a temperature of 170-200° C. and for a time of 15-20 h.

Images