Offshore wind power yaw brake pad and preparation method thereof

Abstract

The invention provides an offshore wind power yaw brake pad and a preparation method thereof, and relates to the technical field of wind power generation. A friction body in the wind power yaw brake pad structure is in direct contact with a brake disc and is a core component of the wind power yaw brake pad, and a hydrophobic fiber reinforcing component, a modified bonding component, a friction coefficient adjusting component and a filler component in the friction body cooperate with each other through respective functions; the high humidity resistance, the corrosion resistance, the wear resistance, the friction performance stability and the like of the friction body can be improved in a targeted manner. According to the preparation method of the offshore wind power yaw brake pad, through step-by-step prefabrication and integrated hot press molding and in combination with precise parameter regulation and control, the performance uniformity and interlayer bonding strength of all functional layers of the brake pad are guaranteed, the production efficiency and cost are both considered, and the production cost is reduced. The offshore wind power yaw brake pad which is resistant to high humidity, corrosion and abrasion and stable in friction coefficient is prepared, complex equipment is not needed in the whole technological process, the technology is simple, and the offshore wind power yaw brake pad is suitable for industrial batch production.

Description

Technical Field

[0001] This invention relates to the field of wind power generation technology, specifically to a yaw brake pad for offshore wind power and its manufacturing method. Background Technology

[0002] In offshore wind power generation scenarios, yaw brake pads, as core components ensuring accurate positioning and safe operation of the wind turbine nacelle, face severe challenges from the harsh marine environment. Firstly, in the high humidity and salt spray environment at sea, seawater moisture and salt easily form water films or salt solution films on the surfaces of the brake pads and brake discs. This significantly reduces the friction coefficient between the yaw brake pads and the brake discs, leading to increased braking pressure and difficulty in achieving the designed braking torque, thus causing inaccurate yaw positioning. Secondly, the high humidity and salt spray environment is highly corrosive, corroding the metal components in the yaw brake pads. This reduces the strength of the yaw brake pads, making them prone to detachment during braking, creating a vicious cycle of corrosion and wear. Consequently, the wear rate of yaw brake pads in marine environments is much higher than that in onshore wind turbines, requiring frequent replacements and increasing maintenance costs and downtime. Furthermore, a humid environment can alter the vibration damping characteristics of friction materials. Fluctuations and instability in the coefficient of friction can easily cause vibrations in the braking system, generating harsh noises. This not only affects the working comfort of maintenance personnel, but long-term abnormal vibrations can also damage other components of the yaw system, such as bearings and gears, further reducing the overall reliability of wind power generation equipment.

[0003] Therefore, there is an urgent need to develop yaw brake pads suitable for high humidity and high salt spray environments at sea, which can solve the problems of reduced friction coefficient, easy corrosion, easy wear and large fluctuation of friction coefficient caused by high humidity and high salt environment at sea. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a yaw brake pad for offshore wind power and its manufacturing method. The yaw brake pad for offshore wind power has advantages such as high humidity resistance, corrosion resistance, wear resistance, and stable friction coefficient.

[0005] The specific technical solution of this invention is as follows: In a first aspect, the present invention provides a yaw brake pad for offshore wind power, comprising a friction body, a resin fiber reinforced backing plate, and an adhesive layer located between the friction body and the resin fiber reinforced backing plate. The friction body comprises a hydrophobic fiber reinforcing component, a modified adhesive component, a friction coefficient adjusting component, and a filler component. The raw material composition of the hydrophobic fiber reinforcing component includes aramid fiber, basalt fiber, sepiolite fiber, and copper fiber, and the surface of each fiber in the hydrophobic fiber reinforcing component has a hydrophobic layer. The raw material composition of the modified adhesive component includes modified phenolic resin and nitrile rubber powder. The modified phenolic resin contains a molybdenum compound. The raw material composition of the friction coefficient adjusting component includes flake graphite, molybdenum disulfide, mica powder, bauxite, boron nitride, and silicon carbide.

[0006] In one possible embodiment, the raw material composition of the friction body contains the following components in weight percentage: aramid fiber 3wt.%-8wt.%, basalt fiber 3wt.%-7wt.%, sepiolite fiber 2wt.%-5wt.%, copper fiber 1wt.%-3wt.%, modified phenolic resin 8wt.%-12wt.%, nitrile rubber powder 2wt.%-5wt.%, flake graphite 1wt.%-3wt.%, molybdenum disulfide 2wt.%-6wt.%, mica powder 3wt.%-10wt.%, bauxite 1wt.%-5wt.%, boron nitride 1wt.%-5wt.%, and silicon carbide 1wt.%-5wt.%.

[0007] In one possible implementation, the hydrophobic layer is formed by first immersing the fiber in a hydrolysis solution of a silane coupling agent, then drying it at 60-100 °C, and then curing it at 100-130 °C to form a hydrophobic layer on the fiber surface. The silane coupling agent is selected from at least one of hexadecyltrimethoxysilane, epoxysilane, and methacryloxysilane.

[0008] In one possible embodiment, the modified phenolic resin contains a molybdenum compound at a mass percentage of 3 wt.%-8 wt.%, and the molybdenum compound is ammonium molybdate.

[0009] In one possible embodiment, the modified phenolic resin further contains an additive selected from at least one of benzoxazine, melamine, and aromatic hydrocarbons, wherein the mass percentage of the additive in the modified phenolic resin is 3wt.%-8wt.%.

[0010] In one possible implementation, the raw materials for the filler component include lightweight filler, dispersion reinforcing filler, functional filler, and modified phenolic resin. The lightweight filler is expanded vermiculite powder, the dispersion reinforcing filler is potassium hexatitanate whiskers, and the functional filler is wear-resistant talc powder, expanded vermiculite powder, and diatomaceous earth.

[0011] In one possible implementation, the raw material composition of the filler component contains the following components in mass percentage: 5wt.%-15wt.% expanded vermiculite powder, 5wt.%-10wt.% diatomaceous earth, 10wt.%-30wt.% calcium carbonate powder, 2wt.%-5wt.% talc powder, and 1wt.%-3wt.% potassium hexatite whiskers.

[0012] In one possible embodiment, the raw material composition of the adhesive layer contains the following components in weight percentage: 40wt.%-60wt.% phenolic resin, 45wt.%-55wt.% epoxy resin, and 1wt.%-5wt.% hydrophilic fiber, wherein the hydrophilic fiber is chopped glass fiber and / or carbon fiber, and the length of the hydrophilic fiber is 1-3 mm.

[0013] In one possible embodiment, the raw material composition of the resin fiber reinforced backing plate contains the following components in weight percentage: 10wt.%-15wt.% chopped carbon fiber, 15wt.%-30wt.% glass fiber, 5wt.%-15wt.% sepiolite fiber, 20wt.%-40wt.% 200-mesh pitch coke, 3wt.%-10wt.% corundum powder, 5wt.%-15wt.% 40-60-mesh pitch coke, and 10wt.%-20wt.% phenolic resin.

[0014] In one possible implementation, the thickness ratio of the friction body, the adhesive layer, and the resin fiber reinforced backing plate is (6-8):(0.1-0.2):(8-10).

[0015] Secondly, the present invention also provides a method for preparing the above-mentioned yaw brake pad for offshore wind power, comprising the following steps: S1. Preparation of friction body pre-powder: After the hydrophobic fiber reinforcing component, modified binder component and filler component are premixed evenly, the friction coefficient adjusting component is added and mixed evenly to obtain the friction body pre-powder. S2. Preparation of adhesive layer pre-powder: Add the adhesive layer raw material to an organic solvent and mix evenly, then dry to remove the organic solvent to obtain the adhesive layer material; S3. Preparation of backplate pre-formed powder: After the raw materials of the backplate are mixed evenly, the backplate pre-formed powder is obtained. S4. Integrated hot pressing molding: The friction body pre-powder, the adhesive layer pre-powder, and the back plate pre-powder are sequentially added to the mold of the hot pressing molding machine. The mass ratio of the friction body pre-powder, the adhesive layer pre-powder, and the back plate pre-powder is controlled to be (80-120):(0.5-2):(80-100). Integrated hot pressing molding is carried out at 170-190℃ and 200-500 KGF pressure. After molding, it is cured at 170-190℃ to obtain the yaw brake pad for offshore wind power.

[0016] The positive and progressive effects of this invention are as follows: Compared with existing technologies, this invention provides a yaw brake pad for offshore wind power and its manufacturing method. The friction element in its structure directly contacts the brake disc and is the core component of the yaw brake pad. The hydrophobic fiber reinforcing component, modified bonding component, friction coefficient adjusting component, and filler component in the friction element work synergistically to specifically improve the friction element's resistance to high humidity, corrosion, wear, and frictional stability. The manufacturing method of the offshore wind power yaw brake pad, through step-by-step prefabrication and integrated hot pressing, combined with precise parameter control, ensures both the uniformity of performance and interlayer bonding strength of each functional layer of the brake pad, while also considering production efficiency and cost. This results in an offshore wind power yaw brake pad that is resistant to high humidity, corrosion, wear, and has a stable friction coefficient. Furthermore, the entire process requires no complex equipment, is simple, and is suitable for industrial mass production. Attached Figure Description

[0017] Figure 1 The curve of the dynamic friction coefficient of the offshore wind power yaw brake pad prepared in Example 1 during the 99th dynamic friction test.

[0018] Figure 2 The graph shows the coefficient of dynamic friction of the offshore wind turbine yaw brake pads prepared in Example 1 during the 199th dynamic friction test.

[0019] Figure 3 The curve of the dynamic friction coefficient of the offshore wind power yaw brake pad prepared in Example 1 during the 299th dynamic friction test.

[0020] Figure 4 The graph shows the static friction coefficient of the yaw brake pads for offshore wind power prepared in Example 1.

[0021] Figure 5 This is a comparison diagram of the corrosion of the wind turbine yaw brake pads in Example 1 and Comparative Example 1. Detailed Implementation

[0022] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. It should be noted that the following embodiments are only used to illustrate the implementation methods and typical parameters of the present invention, and are not intended to limit the parameter range described in the present invention. Reasonable variations derived therefrom are still within the protection scope of the present invention.

[0023] It should be noted that the endpoints and any values ​​of the ranges 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 endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0024] Unless otherwise defined, all terms, symbols, and other scientific terms used herein are intended to have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In some instances, terms having a conventional meaning are defined herein for clarification or ease of reference, and such definitions should not be construed as indicating a significant difference from conventional understanding in the art. The technical methods described or referenced herein are generally well understood by those skilled in the art and employed by conventional methods. Unless otherwise stated, the use of commercially available kits, reagents, and instruments shall be performed according to the manufacturer's instructions and parameters.

[0025] The specific technical solution of this invention is as follows: In a first aspect, the present invention provides a yaw brake pad for offshore wind power, comprising a friction body, a resin fiber reinforced backing plate, and an adhesive layer located between the friction body and the resin fiber reinforced backing plate. The friction body comprises a hydrophobic fiber reinforcing component, a modified adhesive component, a friction coefficient adjusting component, and a filler component. The raw material composition of the hydrophobic fiber reinforcing component includes aramid fiber, basalt fiber, sepiolite fiber, and copper fiber, and the surface of each fiber in the hydrophobic fiber reinforcing component has a hydrophobic layer. The raw material composition of the modified adhesive component includes modified phenolic resin and nitrile rubber powder. The modified phenolic resin contains a molybdenum compound. The raw material composition of the friction coefficient adjusting component includes flake graphite, molybdenum disulfide, mica powder, bauxite, boron nitride, and silicon carbide.

[0026] The present invention provides a yaw brake pad for offshore wind power, wherein the friction body in its structure is in direct contact with the brake disc and is the core component of the wind power yaw brake pad. The hydrophobic fiber reinforcing component, modified bonding component, friction coefficient adjusting component and filler component in the friction body can improve the friction body’s resistance to high humidity, corrosion, wear and friction performance stability through their respective functions. Firstly, the hydrophobic fiber reinforcement component, with hydrophobically modified fibers as its core, achieves enhanced wear resistance and corrosion resistance through fiber selection and the formation of a hydrophobic layer. Aromatic fibers, being organic fibers, possess high toughness, high tensile strength, and chemical corrosion resistance, which are beneficial for improving the wear resistance and corrosion resistance of the friction body. Basalt fibers and sepiolite fibers, being inorganic mineral fibers, have good acid and alkali resistance. Basalt fibers also have high hardness and high wear resistance, while sepiolite fibers have a natural porous structure, which can improve the corrosion resistance, wear resistance, and hydrophobicity of the friction body. Copper fibers have excellent thermal conductivity, which can quickly dissipate heat from the friction surface, and the surface easily forms a dense oxide film, which can resist atmospheric corrosion. The hydrophobic layer on the fiber surface can significantly reduce the surface energy of the friction body, making it difficult for the surface of the friction body to be wetted. Water molecules in the high humidity environment of the ocean cannot form a water film between the brake pads and the brake disc, allowing the friction body to maintain a high and stable coefficient of friction even in the high humidity environment of the ocean. Secondly, the bonding components utilize modified phenolic resin and nitrile rubber powder to ensure the overall structural stability, corrosion resistance, and wear resistance of the yaw brake pads. By adding molybdenum compounds to the phenolic resin, the molybdenum compounds can form a cross-linked structure with the phenolic resin, improving the hydrolysis resistance and oxidation resistance of the phenolic resin, thereby resisting the degradation and oxidation of the phenolic resin caused by sea moisture. Nitrile rubber powder can impart a certain degree of elasticity to the friction body, which can buffer the impact load during braking and prevent the friction body from cracking due to impact. At the same time, the micro-elasticity of the friction body can adaptively fit with the brake disc, indirectly ensuring the stability of the friction coefficient. Furthermore, the friction coefficient regulating components ensure the stability of the friction coefficient of the friction body through lubrication-wear enhancement and wear stabilization synergy. Flake graphite, molybdenum disulfide, and boron nitride are all layered solid lubricants that can form a lubricating film at the friction interface during braking, stabilizing the friction coefficient and reducing noise and vibration. Bauxite and silicon carbide are both high-hardness inorganic particles that can embed into the surface of the friction body, playing a role in wear enhancement. The soft layered structure of mica powder can buffer the hard impact of bauxite and silicon carbide during friction, preventing the friction coefficient from dropping sharply due to particle shedding, which is conducive to achieving dynamic stability of the friction coefficient. In summary, the above technical features work together to ensure that the brake pads are not corroded by high humidity salt spray or fail due to brake wear during long-term service at sea, while maintaining a stable friction coefficient.

[0027] In one possible embodiment, the raw material composition of the friction body contains the following components in weight percentage: aramid fiber 3wt.%-8wt.%, basalt fiber 3wt.%-7wt.%, sepiolite fiber 2wt.%-5wt.%, copper fiber 1wt.%-3wt.%, modified phenolic resin 8wt.%-12wt.%, nitrile rubber powder 2wt.%-5wt.%, flake graphite 1wt.%-3wt.%, molybdenum disulfide 2wt.%-6wt.%, mica powder 3wt.%-10wt.%, bauxite 1wt.%-5wt.%, boron nitride 1wt.%-5wt.%, and silicon carbide 1wt.%-5wt.%. The mass percentage ratio of the above-mentioned friction material, through the synergistic proportion and complementary performance of each functional component, achieves precise optimization of the performance of offshore wind power yaw brake pads. This enables the friction material to simultaneously possess excellent resistance to high humidity corrosion, wear resistance, and stable friction performance, meeting the stringent requirements of offshore wind power yaw braking and providing key raw material ratio support for the long-term reliable operation of offshore wind power yaw brake pads.

[0028] In one possible implementation, the hydrophobic layer is formed by first immersing the fiber in a hydrolysis solution of a silane coupling agent, then drying it at 60-100 °C, and then curing it at 100-130 °C to form a hydrophobic layer on the fiber surface. The silane coupling agent is selected from at least one of hexadecyltrimethoxysilane, epoxysilane, and methacryloxysilane. The above-mentioned method for forming a hydrophobic layer involves first impregnating the fiber surface with a hydrolyzed solution of the silane coupling agent to ensure uniform coverage of the hydrophobic components; drying at 60-100℃ removes excess water from the hydrolyzed solution of the silane coupling agent adhering to the fiber surface, preventing pores from forming due to water evaporation during subsequent curing and affecting the hydrophobic integrity; curing at 100-130℃ promotes a chemical reaction between the silane coupling agent and the hydroxyl groups on the fiber surface, forming a dense hydrophobic film with chemical bonds. Compared to simple physical coating, this chemically bonded hydrophobic layer is less likely to detach during the preparation of the friction body or braking wear, and can block the contact between water vapor and the fiber in the high-humidity marine environment for a long time, preventing fiber corrosion and hydrolysis and maintaining the structural stability of the friction body. Hexadecyltrimethoxysilane, epoxysilane, and methacryloxysilane all possess excellent hydrophobic properties and can provide excellent hydrophobic performance when used to prepare hydrophobic layers.

[0029] In one possible embodiment, the modified phenolic resin contains a molybdenum compound at a mass percentage of 3 wt.%-8 wt.%, and the molybdenum compound is ammonium molybdate. The 3%-8% mass percentage of ammonium molybdate in the modified phenolic resin can both enhance the intermolecular forces of the phenolic resin through crosslinking, thereby increasing the carbonization temperature of the phenolic resin to suit high-temperature application environments, and maintain the resin's toughness to withstand impact loads during braking.

[0030] In one possible embodiment, the modified phenolic resin further contains an additive selected from at least one of benzoxazine, melamine, and aromatic hydrocarbons, wherein the mass percentage of the additive in the modified phenolic resin is 3 wt.%-8 wt.%. Introducing at least one of benzoxazine, melamine, and aromatic hydrocarbons into the phenolic resin can further improve the acid and alkali resistance and corrosion resistance of the friction element.

[0031] In one possible implementation, the raw materials for the filler component include lightweight filler, dispersion reinforcing filler, functional filler, and modified phenolic resin. The lightweight filler is expanded vermiculite powder, the dispersion reinforcing filler is potassium hexatitanate whiskers, and the functional filler is wear-resistant talc powder, expanded vermiculite powder, and diatomaceous earth. Expanded vermiculite powder has a low density, which can replace some high-density components (such as metal fibers and high-cost reinforcing materials), reducing the overall density of the friction body and decreasing the rotational load on the brake disc. Simultaneously, its low raw material cost reduces brake pad manufacturing costs while ensuring the strength of the friction body. Furthermore, its porous structure can adsorb friction debris, further reducing abrasive wear. Potassium hexatite whiskers possess high tensile strength and corrosion resistance, and are dispersed within the friction body, enhancing its impact and tensile strength to withstand instantaneous loads and abrasive cutting during braking. Talc powder exhibits excellent lubricity and formability, reducing frictional resistance between the friction body and brake disc, minimizing bidirectional wear, and improving the fluidity during friction body forming, preventing bubbles and cracks. Diatomaceous earth has strong adsorption properties, adsorbing minute metal debris and phenolic resin degradation products generated during braking, preventing fluctuations in the friction coefficient caused by abrasive accumulation.

[0032] In one possible implementation, the raw material composition of the filler component contains the following components in mass percentage: 5wt.%-15wt.% expanded vermiculite powder, 5wt.%-10wt.% diatomaceous earth, 10wt.%-30wt.% calcium carbonate powder, 2wt.%-5wt.% talc powder, and 1wt.%-3wt.% potassium hexatite whiskers. Calcium carbonate powder, at a proportion of 10wt.%-30wt.%, serves as an inexpensive inorganic filler, significantly reducing raw material costs while ensuring the compactness of the friction body structure. Expanded vermiculite powder, at a proportion of 5wt.%-15wt.%, offsets the density increase caused by the 10wt.%-30wt.% calcium carbonate through its lightweight properties, keeping the overall density of the friction body within a suitable range. Diatomaceous earth, at a proportion of 5wt.%-10wt.%, efficiently adsorbs metal debris and resin degradation products generated during braking, while its porous structure adjusts the porosity of the friction body, balancing heat dissipation and water vapor permeability resistance. Talc powder, at a proportion of 2wt.%-5wt.%, acts as a lubricating filler, forming a thin lubricating film at the friction interface, reducing hard wear between the friction body and the brake disc while ensuring that the coefficient of friction of the friction body remains at a high value, thus guaranteeing braking reliability. Although the proportion of potassium hexatite whiskers is low, at a proportion of 1wt.%-3wt.%, it is sufficient to form a microscopic support framework inside the friction body, significantly improving the impact strength and tensile properties of the friction body.

[0033] In one possible implementation, the adhesive layer comprises the following components by weight percentage: 40 wt.%-60 wt.% phenolic resin, 45 wt.%-55 wt.% epoxy resin, and 1 wt.%-5 wt.% hydrophilic fiber, wherein the hydrophilic fiber is chopped glass fiber and / or carbon fiber, and the length of the hydrophilic fiber is 1-3 mm. The phenolic resin in the adhesive layer possesses high-temperature resistance and can form a good interfacial bond with the modified phenolic resin in the friction element, thereby improving the bonding force with the friction element; the epoxy resin has high bonding strength and can tightly adhere to the resin fiber reinforced backing plate, improving interlayer adhesion. The 40%-60% phenolic resin and 45%-55% friction element proportions are close, balancing high-temperature resistance and high bonding strength, making it suitable for the alternating high and low temperature operating conditions of offshore wind power braking.

[0034] In one possible embodiment, the raw material composition of the resin fiber reinforced backing plate contains the following components in weight percentage: 10wt.%-15wt.% chopped carbon fiber, 15wt.%-30wt.% glass fiber, 5wt.%-15wt.% sepiolite fiber, 20wt.%-40wt.% 200-mesh pitch coke, 3wt.%-10wt.% corundum powder, 5wt.%-15wt.% 40-60-mesh pitch coke, and 10wt.%-20wt.% phenolic resin. In the resin fiber reinforced backsheet, 10wt.%-15wt.% chopped carbon fiber, 15wt.%-30wt.% glass fiber, and 5wt.%-15wt.% sepiolite fiber are used. This combines the high tensile strength and excellent corrosion resistance of chopped carbon fiber, the cost-effectiveness and good insulation of glass fiber, and the porous structure of sepiolite fiber to construct a reinforcing network that balances high strength, corrosion resistance, and good heat dissipation at low cost. 20wt.%-40wt.% 200-mesh fine pitch coke fills the micropores between the fibers and resin, reducing the porosity of the backsheet and improving structural density and dimensional stability. 5wt.%-15wt.% The 40-60 mesh coarse pitch coke (wt.%) adjusts the backplate density through particle size distribution, while also providing the backplate with appropriate elastic buffer space; the 3-10 wt.% corundum powder, as a high-hardness filler, can improve the wear resistance of the backplate surface and reduce wear loss at the interface between the backplate and the friction body during braking; the combination of 200 mesh fine pitch coke, 40-60 mesh coarse pitch coke, and corundum powder enables the backplate to maintain structural strength while also possessing lightweight and low-wear characteristics, making it suitable for long-term braking conditions; the 10-20 wt.% phenolic resin, as a binder matrix, can firmly bond the fibers, pitch coke, and corundum powder to form a homogeneous composite structure.

[0035] In one possible implementation, the thickness ratio of the friction element, the adhesive layer, and the resin fiber reinforced backing plate is (6-8):(0.1-0.2):(8-10). When the thicknesses of the friction element, the adhesive layer, and the resin fiber reinforced backing plate are within the above-mentioned ratio range, it ensures that the backing plate provides reliable support for the friction element, guarantees braking efficiency through the reasonable thickness of the friction element, and achieves interface stability with the help of the ultra-thin adhesive layer. This ensures the overall structural strength, braking stability, and wear resistance of the yaw brake pad, adapting to the long-term service requirements under the complex operating conditions of offshore wind power.

[0036] Secondly, the present invention also provides a method for preparing the above-mentioned yaw brake pad for offshore wind power, comprising the following steps: S1. Preparation of friction body pre-powder: After the hydrophobic fiber reinforcing component, modified binder component and filler component are premixed evenly, the friction coefficient adjusting component is added and mixed evenly to obtain the friction body pre-powder. S2. Preparation of adhesive layer pre-powder: Add the adhesive layer raw material to alcohol and mix evenly, then dry to remove the alcohol to obtain the adhesive layer material; S3. Preparation of backplate pre-formed powder: After the raw materials of the backplate are mixed evenly, the backplate pre-formed powder is obtained. S4. Integrated hot pressing molding: The friction body pre-powder, the adhesive layer pre-powder, and the back plate pre-powder are sequentially added to the mold of the hot pressing molding machine. The mass ratio of the friction body pre-powder, the adhesive layer pre-powder, and the back plate pre-powder is controlled to be (80-120):(0.5-2):(80-100). Integrated hot pressing molding is performed at 170-190℃ and 200-500 KGF pressure. After molding, it is cured at 170-190℃ to obtain the yaw brake pad.

[0037] The present invention provides a method for preparing yaw brake pads for offshore wind power. Through step-by-step prefabrication and integrated hot pressing, combined with precise parameter control, a yaw brake pad with high humidity resistance, corrosion resistance, wear resistance, and a stable friction coefficient is obtained. In step S1, hydrophobic fiber reinforcement components, modified binder components, and filler components are premixed, and then a friction coefficient adjusting component is added. Step-by-step mixing ensures uniform dispersion of the functional components of the friction body, guaranteeing wear resistance and high humidity resistance. In step S2, the binder layer raw material is first dissolved in alcohol and then dried. The fluidity of alcohol allows for homogeneous mixing of phenolic resin and epoxy resin with hydrophilic fibers. In step S3, the backplate raw material is directly and uniformly mixed, ensuring the formation of a stable reinforcing network from chopped carbon fiber, glass fiber, and pitch coke. The friction body, binder layer, and backplate pre-powder are sequentially stacked and hot-pressed, rather than being prepared separately and then spliced. The fluidity of the resin during hot pressing (e.g., modified phenolic resin in the friction body, phenolic resin and epoxy resin in the binder layer, and phenolic resin in the backplate) enables molecular-level bonding at the interlayer interfaces. Compared to splicing processes, integrated hot pressing eliminates interlayer gaps, blocks the penetration channels of high-humidity salt spray at sea, and avoids interlayer delamination; the hot pressing temperature of 170-190℃ matches the curing temperature, ensuring that each layer of resin is fully cured to form a stable cross-linked structure, improving high-temperature resistance and hydrolysis resistance, while avoiding fiber damage caused by excessive temperature; the pressure of 200-500 KGF can compact each layer of material, reduce internal porosity, and improve the density of the friction body and the rigidity of the backing plate structure. The mass ratio of friction body pre-powder, adhesive layer pre-powder, and backplate pre-powder is (80-120):(0.5-2):(80-100), which matches the thickness ratio of friction body, adhesive layer, and backplate pre-powder (6-8):(0.1-0.2):(8-10). This ensures precise and controllable thickness of each layer and avoids excessively thick or thin functional layers due to imbalances in mass ratio. Furthermore, the entire process requires no complex equipment, is simple, and suitable for industrial mass production. In addition, the integrated molding process reduces subsequent assembly steps, lowers the risk of brake pad performance fluctuations due to assembly errors, ensures consistent performance of each brake pad, and meets the stability requirements of offshore wind power for mass application of equipment. In summary, this preparation method, through scientific step-by-step prefabrication, integrated hot pressing, and parameter control, not only ensures the performance uniformity and interlayer bonding strength of each functional layer of the brake pad, but also takes into account production efficiency and cost. It can stably produce yaw brake pads that meet the requirements of high humidity, high salt spray, high corrosion resistance, and high friction stability in offshore wind power.

[0038] The technical solution of the present invention will be further described below with reference to specific embodiments and comparative examples. All reagents used in the embodiments are commercially available or synthesized by conventional methods and can be used directly without further processing. The instruments used in the embodiments are also commercially available.

[0039] Example 1 This embodiment provides a yaw brake pad for offshore wind power, comprising a friction body, a resin fiber reinforced backing plate, and an adhesive layer located between the friction body and the resin fiber reinforced backing plate. The friction body is composed of a hydrophobic fiber reinforcement component, a modified adhesive component, a friction coefficient adjusting component, and a filler component. The hydrophobic fiber reinforcement component contains the following components by mass percentage: 5 wt.% aramid fiber, 5 wt.% basalt fiber, 5 wt.% sepiolite fiber, and 1 wt.% copper fiber, wherein the lengths of the aramid fiber, basalt fiber, sepiolite fiber, and copper fiber are 3-5 mm. The surface of the friction element is covered with hexadecyltrimethoxysilane, making it difficult for a water film to form on the surface of the friction element, thus enhancing its hydrophobicity. The modified binder component contains the following components by mass percentage: 8 wt.% modified phenolic resin and 2 wt.% nitrile rubber powder. The modified phenolic resin contains 6 wt.% ammonium molybdate and 6 wt.% benzoxazine, which can enhance the friction element's resistance to oxidation, acids, alkalis, and corrosion. The component for adjusting the friction coefficient contains the following components by mass percentage: 1 wt.% flake graphite and 6 wt.% molybdenum disulfide. The raw material composition of the filler component contains the following components by weight percentage: expanded vermiculite powder 15wt.%, powdered diatomaceous earth 10wt.%, calcium carbonate powder 19wt.%, talc powder 5wt.%, and potassium hexatitanate whiskers 1wt.%; the raw material composition of the binder layer contains the following components by weight percentage: 40wt.% phenolic resin, 55wt.% epoxy resin, and 5wt.% hydrophilic chopped glass fiber, the length of which is 1... mm; The raw material composition of the resin fiber reinforced backing plate contains the following components by weight percentage: 15wt.% chopped carbon fiber, 20wt.% glass fiber, 15wt.% sepiolite fiber, 20wt.% 200 mesh pitch coke, 10wt.% corundum powder, 10wt.% 40-60 mesh pitch coke and 10wt.% phenolic resin. The resin fiber and the pitch coke of varying coarse and fine textures are organically combined to form a lightweight, high-strength and corrosion-resistant backing plate material.

[0040] Example 2 This embodiment provides a yaw brake pad for offshore wind power, comprising a friction body, a resin fiber reinforced backing plate, and an adhesive layer located between the friction body and the resin fiber reinforced backing plate. The friction body is composed of a hydrophobic fiber reinforcement component, a modified adhesive component, a friction coefficient adjusting component, and a filler component. The raw material composition of the hydrophobic fiber reinforcement component contains the following components by mass percentage: 3 wt.% aramid fiber, 7 wt.% basalt fiber, 4 wt.% sepiolite fiber, and 1 wt.% copper fiber, wherein the lengths of the aramid fiber, basalt fiber, sepiolite fiber, and copper fiber are 3-5 mm. The friction body is made of mm thick and has a hexadecyltrimethoxysilane hydrophobic layer on its surface, making it difficult for a water film to form on the surface of the friction body, thus enhancing the hydrophobicity of the friction body. The modified binder component contains the following components by mass percentage: 9 wt.% modified phenolic resin and 5 wt.% nitrile rubber powder. The modified phenolic resin contains 5 wt.% ammonium molybdate and 6 wt.% melamine by mass, which can enhance the oxidation resistance, acid and alkali resistance and corrosion resistance of the friction body. The raw material composition for adjusting the friction coefficient contains the following components by mass percentage: 1 wt.% flake graphite and 4 wt.% molybdenum disulfide. The raw material composition of the filler component contains the following components by mass percentage: expanded vermiculite powder 10 wt.%, powdered diatomaceous earth 10 wt.%, calcium carbonate powder 28 wt.%, talc powder 5 wt.%, and potassium hexatite whiskers 3 wt.%; the raw material composition of the binder layer contains the following components by mass percentage: 45 wt.% phenolic resin, 50 wt.% epoxy resin, and 5 wt.% hydrophilic chopped glass fiber, the length of which is 1.5 mm. mm; The raw material composition of the resin fiber reinforced backing plate contains the following components by weight percentage: 11wt.% chopped carbon fiber, 20wt.% glass fiber, 14wt.% sepiolite fiber, 25wt.% 200 mesh pitch coke, 5wt.% corundum powder, 10wt.% 40-60 mesh pitch coke and 15wt.% phenolic resin. The resin fiber and the pitch coke of varying coarse and fine textures are organically combined to form a lightweight, high-strength and corrosion-resistant backing plate material.

[0041] Example 3 This embodiment provides a yaw brake pad for offshore wind power, comprising a friction body, a resin fiber reinforced backing plate, and an adhesive layer located between the friction body and the resin fiber reinforced backing plate. The friction body is composed of a hydrophobic fiber reinforcement component, a modified adhesive component, a friction coefficient adjusting component, and a filler component. The raw material composition of the hydrophobic fiber reinforcement component contains the following components by mass percentage: 4 wt.% aramid fiber, 4 wt.% basalt fiber, 4 wt.% sepiolite fiber, and 3 wt.% copper fiber, wherein the lengths of the aramid fiber, basalt fiber, sepiolite fiber, and copper fiber are 3-5 mm. The friction elements are all mm thick and have an epoxy silane hydrophobic layer on their surfaces, making it difficult for water films to form on the surface of the friction elements, thus enhancing their hydrophobicity. The modified binder component contains the following components by mass percentage: 10 wt.% modified phenolic resin and 4 wt.% nitrile rubber powder. The modified phenolic resin contains 5 wt.% ammonium molybdate and 6 wt.% melamine, which can enhance the oxidation resistance, acid and alkali resistance, and corrosion resistance of the friction elements. The raw material component for adjusting the friction coefficient contains the following components by mass percentage: 2 wt.% flake graphite and 3 wt.% molybdenum disulfide. The raw material composition of the filler component contains the following components by weight percentage: expanded vermiculite powder 11 wt.%, powdered diatomaceous earth 11 wt.%, calcium carbonate powder 28 wt.%, talc powder 5 wt.%, and potassium hexatite whiskers 1 wt.%; the raw material composition of the binder layer contains the following components by weight percentage: 50 wt.% phenolic resin, 46 wt.% epoxy resin, and 4 wt.% hydrophilic chopped glass fiber, the length of which is 1.5 mm. mm; The raw material composition of the resin fiber reinforced backing plate contains the following components by weight percentage: 12wt.% chopped carbon fiber, 21wt.% glass fiber, 7wt.% sepiolite fiber, 20wt.% 200 mesh pitch coke, 10wt.% corundum powder, 10wt.% 40-60 mesh pitch coke and 10wt.% phenolic resin. The resin fiber and the pitch coke of varying coarse and fine textures are organically combined to form a lightweight, high-strength and corrosion-resistant backing plate material.

[0042] Example 4 This embodiment provides a yaw brake pad for offshore wind power, comprising a friction body, a resin fiber reinforced backing plate, and an adhesive layer located between the friction body and the resin fiber reinforced backing plate. The friction body is composed of a hydrophobic fiber reinforcement component, a modified adhesive component, a friction coefficient adjusting component, and a filler component. The raw material composition of the hydrophobic fiber reinforcement component contains the following components by mass percentage: 6 wt.% aramid fiber, 4 wt.% basalt fiber, 3 wt.% sepiolite fiber, and 1 wt.% copper fiber, and the lengths of the aramid fiber, basalt fiber, sepiolite fiber, and copper fiber are 3-5 mm. The friction body is made of mm thick and has an epoxy silane hydrophobic layer on its surface, making it difficult for a water film to form on the surface of the friction body, thus enhancing the hydrophobicity of the friction body. The modified binder component contains the following components by mass percentage: 11 wt.% modified phenolic resin and 3 wt.% nitrile rubber powder. The modified phenolic resin contains 7 wt.% ammonium molybdate and 5 wt.% melamine by mass, which can enhance the oxidation resistance, acid and alkali resistance and corrosion resistance of the friction body. The raw material component for adjusting the friction coefficient contains the following components by mass percentage: 2 wt.% flake graphite and 3 wt.% molybdenum disulfide. The raw materials of the filler component contain the following components by weight percentage: expanded vermiculite powder 6 wt.%, powdered diatomaceous earth 12 wt.%, calcium carbonate powder 30 wt.%, talc powder 5 wt.%, and potassium hexatite whiskers 3 wt.%; the raw materials of the binder layer contain the following components by weight percentage: 40 wt.% phenolic resin, 55 wt.% epoxy resin, and 5 wt.% hydrophilic carbon fiber with a length of 1.5 mm. mm; The raw material composition of the resin fiber reinforced backing plate contains the following components by weight percentage: 11wt.% chopped carbon fiber, 21wt.% glass fiber, 5wt.% sepiolite fiber, 33wt.% 200 mesh pitch coke, 6wt.% corundum powder, 20wt.% 40-60 mesh pitch coke and 10wt.% phenolic resin. The resin fiber and the pitch coke of varying coarse and fine textures are organically combined to form a lightweight, high-strength and corrosion-resistant backing plate material.

[0043] Example 5 This embodiment provides a yaw brake pad for offshore wind power, comprising a friction body, a resin fiber reinforced backing plate, and an adhesive layer located between the friction body and the resin fiber reinforced backing plate. The friction body is composed of a hydrophobic fiber reinforcement component, a modified adhesive component, a friction coefficient adjusting component, and a filler component. The hydrophobic fiber reinforcement component contains the following components by mass percentage: 7 wt.% aramid fiber, 5 wt.% basalt fiber, 2 wt.% sepiolite fiber, and 1 wt.% copper fiber, wherein the lengths of the aramid fiber, basalt fiber, sepiolite fiber, and copper fiber are 3-5 mm. The friction elements are all mm thick and have a methacryloxysilane hydrophobic layer on their surface, making it difficult for a water film to form on the surface of the friction element, thus enhancing the hydrophobicity and corrosion resistance of the friction element; the modified binder component contains the following components by mass percentage: 8 wt.% modified phenolic resin and 5 wt.% nitrile rubber powder. The modified phenolic resin contains 4 wt.% ammonium molybdate and 8 wt.% melamine by mass, which can enhance the oxidation resistance, acid and alkali resistance and corrosion resistance of the friction element; the raw material composition for adjusting the friction coefficient contains the following components by mass percentage: 3 wt.% flake graphite. The raw material composition of the filler component includes: 5 wt.% molybdenum disulfide, 3 wt.% mica powder, 2 wt.% bauxite, 2 wt.% boron nitride, and 1 wt.% silicon carbide; the raw material composition of the filler component includes: 14 wt.% expanded vermiculite powder, 9 wt.% powdered diatomaceous earth, 25 wt.% calcium carbonate powder, 5 wt.% talc powder, and 3 wt.% potassium hexatitanate whiskers; the raw material composition of the binder layer includes: 46 wt.% phenolic resin, 50 wt.% epoxy resin, and 4 wt.% hydrophilic carbon fiber, with a carbon fiber length of 2... mm; The raw material composition of the resin fiber reinforced backing plate contains the following components by weight percentage: 11 wt.% chopped carbon fiber, 23 wt.% glass fiber, 9 wt.% sepiolite fiber, 32 wt.% 200 mesh pitch coke, 4 wt.% corundum powder, 11 wt.% 40-60 mesh pitch coke and 10 wt.% phenolic resin. The resin fiber and the pitch coke of varying coarse and fine textures are organically combined to form a lightweight, high-strength and corrosion-resistant backing plate material.

[0044] Example 6 This embodiment provides a method for preparing the yaw brake pad for offshore wind power in Embodiment 1, including the following steps: S0. Raw material pretreatment: First, acetone and deionized water are used to clean and remove impurities from the surface of aramid fibers, basalt fibers, sepiolite fibers and copper fibers. Then, aramid fibers, basalt fibers, sepiolite fibers and copper fibers are impregnated in a hydrolysis solution of hexadecyltrimethoxysilane for 60 min, followed by drying at 80 ℃, and finally high-temperature curing at 100 ℃ for 120 min to form a hexadecyltrimethoxysilane hydrophobic layer on the fiber surface, thus obtaining hydrophobic fiber raw material. Phenolic resin powder, benzoxazine monomer and ammonium molybdate powder are premixed in a mixer, and then melt-blended at 100 ℃ using a heated internal mixer to obtain modified phenolic resin. S1. Preparation of friction body pre-powder: The hydrophobic fiber raw material obtained in step S0, modified phenolic resin, nitrile rubber powder, expanded vermiculite powder, diatomaceous earth, calcium carbonate powder, talc powder, and potassium hexatitanate whiskers are added to a mixing device and premixed for 5 min to form a uniform pre-powder; then flake graphite, molybdenum disulfide, mica powder, bauxite, boron nitride, and silicon carbide are added, and the mixture is first mixed at a high speed of 350 r / min for 10 min, and then mixed at a speed of 450 r / min for 5 min to ensure that each component is uniformly dispersed to obtain the friction body pre-powder; S2. Preparation of adhesive layer pre-powder: Phenolic resin, epoxy resin and chopped glass fiber are added to alcohol and mixed evenly. Then, the mixture is dried at 80°C to remove the alcohol and obtain adhesive layer pre-powder. S3. Preparation of backplate preform powder: Short carbon fiber, glass fiber, and sepiolite fiber (for backplate) are added to a mixing device for premixing, and then 200 mesh pitch coke, corundum powder, 50 mesh pitch coke and phenolic resin are added. First, the mixture is mixed at a high speed of 450 r / min for 10 min, and then mixed at a speed of 600 r / min for 10 min to obtain uniform backplate preform powder. S4. Integrated hot pressing molding: The friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder are sequentially added to the mold of the hot pressing molding machine. The mass ratio of the friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder is controlled to be 100:0.5:100. Integrated hot pressing molding is carried out at 180 ℃ and 300 KGF pressure. After molding, it is cured at 180 ℃ to obtain the yaw brake pad.

[0045] Example 7 This embodiment provides a method for preparing the yaw brake pad for offshore wind power in Embodiment 2, including the following steps: S0. Raw material pretreatment: First, acetone and deionized water are used to clean and remove impurities from the surface of aramid fibers, basalt fibers, sepiolite fibers and copper fibers. Then, aramid fibers, basalt fibers, sepiolite fibers and copper fibers are impregnated in a hydrolysis solution of hexadecyltrimethoxysilane for 60 min, followed by drying at 80 ℃, and finally high-temperature curing at 100 ℃ for 120 min to form a hexadecyltrimethoxysilane hydrophobic layer on the fiber surface, thus obtaining hydrophobic fiber raw material. Phenolic resin powder, benzoxazine monomer and ammonium molybdate powder are premixed in a mixer, and then melt-blended at 100 ℃ using a heated internal mixer to obtain modified phenolic resin. S1. Preparation of friction body pre-powder: The hydrophobic fiber raw material obtained in step S0, modified phenolic resin, nitrile rubber powder, expanded vermiculite powder, diatomaceous earth, calcium carbonate powder, talc powder, and potassium hexatitanate whiskers are added to a mixing device and premixed for 5 min to form a uniform pre-powder; then flake graphite, molybdenum disulfide, mica powder, bauxite, boron nitride, and silicon carbide are added, and the mixture is first mixed at a high speed of 350 r / min for 11 min, and then mixed at a speed of 450 r / min for 6 min to ensure that each component is uniformly dispersed to obtain the friction body pre-powder; S2. Preparation of adhesive layer pre-powder: Phenolic resin, epoxy resin and chopped glass fiber are added to alcohol and mixed evenly. Then, the mixture is dried at 80°C to remove the alcohol and obtain adhesive layer pre-powder. S3. Preparation of backplate preform powder: Short carbon fiber, glass fiber, and sepiolite fiber (for backplate) are added to a mixing device for premixing, and then 200 mesh pitch coke, corundum powder, 50 mesh pitch coke and phenolic resin are added. First, the mixture is mixed at a high speed of 450 r / min for 11 min, and then mixed at a speed of 550 r / min for 11 min to obtain uniform backplate preform powder. S4. Integrated hot pressing molding: The friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder are sequentially added to the mold of the hot pressing molding machine. The mass ratio of the friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder is controlled to be 100:0.6:100. Integrated hot pressing molding is carried out at 175 ℃ and 200 KGF pressure. After molding, it is cured at 170 ℃ for 2 h to obtain the yaw brake pad.

[0046] Example 8 This embodiment provides a method for preparing the yaw brake pad for offshore wind power in Embodiment 2, including the following steps: S0. Raw material pretreatment: First, acetone and deionized water are used to clean and remove impurities from the surface of aramid fibers, basalt fibers, sepiolite fibers and copper fibers. Then, aramid fibers, basalt fibers, sepiolite fibers and copper fibers are impregnated in a hydrolysis solution of hexadecyltrimethoxysilane for 60 min, followed by drying at 80 ℃, and finally high-temperature curing at 100 ℃ for 120 min to form a hexadecyltrimethoxysilane hydrophobic layer on the fiber surface, thus obtaining hydrophobic fiber raw material. Phenolic resin powder, benzoxazine monomer and ammonium molybdate powder are premixed in a mixer, and then melt-blended at 100 ℃ using a heated internal mixer to obtain modified phenolic resin. S1. Preparation of friction body pre-powder: The hydrophobic fiber raw material obtained in step S0, modified phenolic resin, nitrile rubber powder, expanded vermiculite powder, diatomaceous earth, calcium carbonate powder, talc powder, and potassium hexatitanate whiskers are added to a mixing device and premixed for 5 min to form a uniform pre-powder; then flake graphite, molybdenum disulfide, mica powder, bauxite, boron nitride, and silicon carbide are added, and the mixture is first mixed at a high speed of 400 r / min for 12 min, and then mixed at a speed of 500 r / min for 7 min to ensure that each component is uniformly dispersed to obtain the friction body pre-powder; S2. Preparation of adhesive layer pre-powder: Phenolic resin, epoxy resin and chopped glass fiber are added to alcohol and mixed evenly. Then, the mixture is dried at 80 °C to remove the alcohol and obtain adhesive layer pre-powder. S3. Preparation of backplate preform powder: Short carbon fiber, glass fiber, and sepiolite fiber (for backplate) are added to a mixing device for premixing, and then 200 mesh pitch coke, corundum powder, 50 mesh pitch coke and phenolic resin are added. First, the mixture is mixed at a high speed of 400 r / min for 12 min, and then mixed at a speed of 600 r / min for 12 min to obtain uniform backplate preform powder. S4. Integrated hot pressing molding: The friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder are sequentially added to the mold of the hot pressing molding machine. The mass ratio of the friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder is controlled to be 100:1:100. Integrated hot pressing molding is carried out at 180℃ and 300 KGF pressure. After molding, it is cured at 180℃ to obtain the yaw brake pad.

[0047] Example 9 This embodiment provides a method for preparing the yaw brake pad for offshore wind power in Embodiment 2, including the following steps: S0. Raw material pretreatment: First, acetone and deionized water are used to clean and remove impurities from the surface of aramid fibers, basalt fibers, sepiolite fibers and copper fibers. Then, aramid fibers, basalt fibers, sepiolite fibers and copper fibers are impregnated in a hydrolysis solution of hexadecyltrimethoxysilane for 30 min, followed by drying at 60 ℃, and finally high-temperature curing at 130 ℃ for 30 min to form a hexadecyltrimethoxysilane hydrophobic layer on the fiber surface, thus obtaining hydrophobic fiber raw material. Phenolic resin powder, benzoxazine monomer and ammonium molybdate powder are premixed in a mixer, and then melt-blended at 130 ℃ using a heated internal mixer to obtain modified phenolic resin. S1. Preparation of friction body pre-powder: The hydrophobic fiber raw material obtained in step S0, modified phenolic resin, nitrile rubber powder, expanded vermiculite powder, diatomaceous earth, calcium carbonate powder, talc powder, and potassium hexatitanate whiskers are added to a mixing device and premixed for 5 min to form a uniform pre-powder; then flake graphite, molybdenum disulfide, mica powder, bauxite, boron nitride, and silicon carbide are added, and the mixture is first mixed at a high speed of 450 r / min for 13 min, and then mixed at a speed of 550 r / min for 8 min to ensure that each component is uniformly dispersed to obtain the friction body pre-powder; S2. Preparation of adhesive layer pre-powder: Phenolic resin, epoxy resin and chopped glass fiber are added to alcohol and mixed evenly. Then, the mixture is dried at 80 °C to remove the alcohol and obtain adhesive layer pre-powder. S3. Preparation of backplate preform powder: Short carbon fiber, glass fiber, and sepiolite fiber (for backplate) are added to a mixing device for premixing, and then 200 mesh pitch coke, corundum powder, 40 mesh pitch coke and phenolic resin are added. First, the mixture is mixed at a high speed of 550 r / min for 14 min, and then mixed at a speed of 650 r / min for 14 min to obtain uniform backplate preform powder. S4. Integrated hot pressing molding: The friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder are sequentially added to the mold of the hot pressing molding machine. The mass ratio of the friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder is controlled to be 80:0.5:80. Integrated hot pressing molding is carried out at 185℃ and 400 KGF pressure. After molding, it is cured at 185℃ to obtain the yaw brake pad.

[0048] Example 10 This embodiment provides a method for preparing the yaw brake pad for offshore wind power in Embodiment 2, including the following steps: S0. Raw material pretreatment: First, acetone and deionized water are used to clean and remove impurities from the surface of aramid fibers, basalt fibers, sepiolite fibers and copper fibers. Then, aramid fibers, basalt fibers, sepiolite fibers and copper fibers are impregnated in a hydrolysis solution of hexadecyltrimethoxysilane for 90 min, followed by drying at 100 ℃, and finally high-temperature curing at 130 ℃ for 180 min to form a hexadecyltrimethoxysilane hydrophobic layer on the fiber surface, thus obtaining hydrophobic fiber raw material. Phenolic resin powder, benzoxazine monomer and ammonium molybdate powder are premixed in a mixer, and then melt-blended at 100 ℃ using a heated internal mixer to obtain modified phenolic resin. S1. Preparation of friction body pre-powder: The hydrophobic fiber raw material obtained in step S0, modified phenolic resin, nitrile rubber powder, expanded vermiculite powder, diatomaceous earth, calcium carbonate powder, talc powder, and potassium hexatitanate whiskers are added to a mixing device and premixed for 5 min to form a uniform pre-powder; then flake graphite, molybdenum disulfide, mica powder, bauxite, boron nitride, and silicon carbide are added, and the mixture is first mixed at a high speed of 500 r / min for 15 min, and then mixed at a speed of 600 r / min for 10 min to ensure that each component is uniformly dispersed to obtain the friction body pre-powder; S2. Preparation of adhesive layer pre-powder: Phenolic resin, epoxy resin and chopped glass fiber are added to alcohol and mixed evenly. Then, the mixture is dried at 80°C to remove the alcohol and obtain adhesive layer pre-powder. S3. Preparation of backplate preform powder: Short carbon fiber, glass fiber, and sepiolite fiber (for backplate) are added to a mixing device for premixing, and then 200 mesh pitch coke, corundum powder, 60 mesh pitch coke and phenolic resin are added. First, the mixture is mixed at a high speed of 600 r / min for 15 min, and then mixed at a speed of 800 r / min for 15 min to obtain uniform backplate preform powder. S4. Integrated hot pressing molding: The friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder are sequentially added to the mold of the hot pressing molding machine. The mass ratio of the friction body pre-powder, adhesive layer pre-powder, and back plate pre-powder is controlled to be 60:1:50. Integrated hot pressing molding is carried out at 190℃ and 450 KGF pressure. After molding, it is cured at 190℃ to obtain the yaw brake pad.

[0049] Comparative Example 1 This comparative example provides a yaw brake pad, which is a commercially available wind power yaw brake pad with model number GWAB 3-120.

[0050] The performance of the yaw brake pads in Examples 1-5 and Comparative Example 1 was tested, and the specific performance data is shown in Table 1: Table 1 Performance test data of yaw brake pads in Examples 1-5 and Comparative Example 1 As shown in Table 1, in the yaw brake pads prepared in Examples 1-5, the flexural strength of the resin fiber reinforced backing plate is greater than 40 MPa, and the compressive strength is greater than 150 MPa. The flexural strength and compressive strength of the friction body reach a maximum of 37.56 MPa and 113.69 MPa, respectively. The weight of the wind power yaw brake pads prepared in Examples 1-5 is between 1.85-1.86 kg, the dynamic friction coefficient μ is between 0.4-0.5, the static friction coefficient μ is between 0.35-0.45, and the wear amount under 35 bar pressure is between 1.1-1.9 × 10⁻⁶. -7 Nm / cm 3 Between the two, the moisture content of the brake pad in the environment is 0.5%, and the water absorption in one month is between 0.18-0.41g. By comparing the performance of the yaw brake pad in Comparative Example 1, it can be seen that the performance of the offshore wind power yaw brake pad provided by the present invention is significantly better than that of commercially available wind power yaw brake pads.

[0051] Figure 1 The graph shows the friction coefficient curve of the offshore wind turbine yaw brake pad prepared in Example 1 during the 99th dynamic friction test. The braking pressure during the dynamic friction test was 34.9 bar and the push-pull speed was 10 mm / s. As can be seen from the graph, the maximum friction coefficient was 0.500, the minimum friction coefficient was 0.404, and the average friction coefficient was 0.455 during the 99th dynamic friction test.

[0052] Figure 2 The graph shows the coefficient of dynamic friction of the offshore wind turbine yaw brake pads prepared in Example 1 during the 199th dynamic friction test. The braking pressure during the dynamic friction test was 35 bar, and the push-pull speed was 10.1 mm / s. As shown in the graph, the maximum coefficient of friction was 0.521, the minimum coefficient of friction was 0.407, and the average coefficient of friction was 0.465 during the 199th dynamic friction test.

[0053] Figure 3 The graph shows the coefficient of dynamic friction of the offshore wind turbine yaw brake pads prepared in Example 1 during the 299th dynamic friction test. The braking pressure during the dynamic friction test was 34.4 bar and the push-pull speed was 10.1 mm / s. As shown in the graph, the maximum coefficient of friction in the 299th dynamic friction test was 0.535, the minimum coefficient of friction was 0.413, and the average coefficient of friction was 0.476.

[0054] Combination Figure 1-3 The data shows that the offshore wind power yaw brake pad provided by the present invention not only has a high coefficient of friction, with an average coefficient of friction greater than 0.45, but also maintains a relatively stable coefficient of friction during 299 consecutive friction tests, indicating that the offshore wind power yaw brake pad provided by the present invention has stable friction performance.

[0055] Figure 4 The graph shows the friction coefficient curve of the offshore wind turbine yaw brake pads prepared in Example 1 during static friction testing. Figure 4 The blue curve represents the push-pull force curve during the static friction test, and the red curve represents the static friction coefficient curve. As shown in the figure, the static friction coefficient of the offshore wind power yaw brake pads prepared in Example 1 is 0.409.

[0056] Figure 5 This is a comparison diagram of the corrosion of the yaw brake pads in Example 1 and Comparative Example 1 after six months of use. Figure 5 Figure (a) is a picture of the yaw brake pads in Comparative Example 1. Figure 5 Figure (b) shows a picture of the yaw brake pad in Example 1. Comparative analysis shows that after six months of use, the yaw brake pad in Comparative Example 1 has a large area of ​​corrosion, while the yaw brake pad in Example 1 has no moisture absorption or corrosion. This indicates that the wind power yaw brake pad provided by the present invention has good corrosion resistance.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions 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 yaw brake pad for offshore wind power, characterized in that, The system comprises a friction element, a resin fiber reinforced backing plate, and an adhesive layer located between the friction element and the resin fiber reinforced backing plate. The friction element consists of a hydrophobic fiber reinforcing component, a modified adhesive component, a friction coefficient adjusting component, and a filler component. The raw materials of the hydrophobic fiber reinforcing component include aramid fiber, basalt fiber, sepiolite fiber, and copper fiber, and the surface of each fiber in the hydrophobic fiber reinforcing component has a hydrophobic layer. The raw materials of the modified adhesive component include modified phenolic resin and nitrile rubber powder. The modified phenolic resin contains a molybdenum compound. The raw materials of the friction coefficient adjusting component include flake graphite, molybdenum disulfide, mica powder, bauxite, boron nitride, and silicon carbide.

2. The yaw brake pad for offshore wind power according to claim 1, characterized in that, The raw material composition of the friction body contains the following components in weight percentage: aramid fiber 3wt.%-8wt.%, basalt fiber 3wt.%-7wt.%, sepiolite fiber 2wt.%-5wt.%, copper fiber 1wt.%-3wt.%, modified phenolic resin 8wt.%-12wt.%, nitrile rubber powder 2wt.%-5wt.%, flake graphite 1wt.%-3wt.%, molybdenum disulfide 2wt.%-6wt.%, mica powder 3wt.%-10wt.%, bauxite 1wt.%-5wt.%, boron nitride 1wt.%-5wt.%, and silicon carbide 1wt.%-5wt.%.

3. The yaw brake pad for offshore wind power according to claim 1, characterized in that, The method for forming the hydrophobic layer is as follows: first, the fiber is immersed in a hydrolysis solution of a silane coupling agent, then dried at 60-100 °C, and then cured at 100-130 °C to form a hydrophobic layer on the surface of the fiber. The silane coupling agent is selected from at least one of hexadecyltrimethoxysilane, epoxysilane, and methacryloxysilane.

4. The yaw brake pad for offshore wind power according to claim 1, characterized in that, In the modified phenolic resin, the mass percentage of the molybdenum compound is 3wt.%-8wt.%, and the molybdenum compound is ammonium molybdate.

5. The yaw brake pad for offshore wind power according to claim 1, characterized in that, The modified phenolic resin also contains additives, which are selected from at least one of benzoxazine, melamine and aromatic hydrocarbons, and the mass percentage of the additives in the modified phenolic resin is 3wt.%-8wt.%.

6. The yaw brake pad for offshore wind power according to claim 1, characterized in that, The raw materials for the filler components include lightweight fillers, dispersion reinforcing fillers, functional fillers, and modified phenolic resin. The lightweight filler is expanded vermiculite powder, the dispersion reinforcing filler is potassium hexatitanate whiskers, and the functional filler is wear-resistant talc powder, expanded vermiculite powder, and diatomaceous earth.

7. The yaw brake pad for offshore wind power according to claim 1, characterized in that, The raw material composition of the filler component contains the following components in mass percentage: 5wt.%-15wt.% expanded vermiculite powder, 5wt.%-10wt.% diatomaceous earth, 10wt.%-30wt.% calcium carbonate powder, 2wt.%-5wt.% talc powder and 1wt.%-3wt.% potassium hexatite whiskers.

8. The yaw brake pad for offshore wind power according to claim 1, characterized in that, The adhesive layer contains the following components by mass percentage: 40wt.%-60wt.% phenolic resin, 45wt.%-55wt.% epoxy resin, and 1wt.%-5wt.% hydrophilic fiber, wherein the hydrophilic fiber is chopped glass fiber and / or carbon fiber, and the length of the hydrophilic fiber is 1-3 mm.

9. The yaw brake pad for offshore wind power according to claim 1, characterized in that, The resin fiber reinforced backing plate contains the following components in weight percentage: 10wt.%-15wt.% chopped carbon fiber, 15wt.%-30wt.% glass fiber, 5wt.%-15wt.% sepiolite fiber, 20wt.%-40wt.% 200-mesh pitch coke, 3wt.%-10wt.% corundum powder, 5wt.%-15wt.% 40-60-mesh pitch coke, and 10wt.%-20wt.% phenolic resin.

10. The yaw brake pad for offshore wind power according to claim 1, characterized in that, The thickness ratio of the friction body, the adhesive layer, and the resin fiber reinforced backing plate is (6-8):(0.1-0.2):(8-10).

11. A method for preparing a yaw brake pad for offshore wind power as described in any one of claims 1-10, characterized in that, Includes the following steps: S1. Preparation of friction body pre-powder: After the hydrophobic fiber reinforcing component, modified binder component and filler component are premixed evenly, the friction coefficient adjusting component is added and mixed evenly to obtain friction body pre-powder. S2. Preparation of adhesive layer pre-powder: Add the adhesive layer raw material to an organic solvent and mix evenly, then dry to remove the organic solvent to obtain the adhesive layer material; S3. Preparation of backplate pre-formed powder: After the raw materials of the backplate are mixed evenly, the backplate pre-formed powder is obtained. S4. Integrated hot pressing molding: The friction body pre-powder, the adhesive layer pre-powder, and the back plate pre-powder are sequentially added to the mold of the hot pressing molding machine. The mass ratio of the friction body pre-powder, the adhesive layer pre-powder, and the back plate pre-powder is controlled to be (80-120):(0.5-2):(80-100). Integrated hot pressing molding is performed at 170-190℃ and 200-500 KGF pressure. After molding, it is cured at 170-190℃ to obtain the yaw brake pad.

Images