Method for preparing wind turbine blade repair resin and method for repairing wind turbine blade

Abstract

The application discloses a preparation method of wind power blade repair resin and a wind power blade repair method. The wind power blade repair resin comprises bisphenol A type epoxy resin, a diluent and an initiator. The diluent is an alicyclic epoxy type diluent. The initiator is one or a combination of cationic initiator and free radical initiator. After mixing and proportioning, the mixed monomers are impregnated with a fabric and coated on a damaged part of the wind power blade. The polymerization reaction of the local coating area is started by using a heat source, a light source or a laser beam. After the polymerization reaction is started, the monomers continuously release heat to maintain the reaction until the mixed monomers in all coating areas are converted into polymers, and the system is completely cured. Compared with the traditional epoxy thermal curing resin, the polymerization process of the resin completely relies on the heat release of the monomers, and the energy consumption is extremely low without external heating. The curing reaction speed is fast, the performance of the cured plate is good, and the efficiency of the wind power blade repair work can be improved.

Description

Technical Field

[0001] This invention relates to the field of wind turbine blade resin material manufacturing, and in particular to a method for preparing a wind turbine blade repair resin and a method for repairing wind turbine blades. Background Technology

[0002] Among the existing components of wind turbines, wind turbine blades are greatly affected by the environment because they are in a state of continuous motion for a long time. At the same time, the manufacturing trend of wind turbine blades towards larger and lighter sizes has also led to their safety factor constantly approaching the lower limit. The combination of these two factors has resulted in frequent occurrences of wind turbine blade damage and other problems.

[0003] In existing technologies, wind turbine blades are mostly repaired using epoxy thermosetting resins, with hand lay-up molding and vacuum injection molding being the most common repair processes. Generally, using these molding methods requires at least 12 hours from preparation to completion of the repair, and the repaired area can achieve 50-70% of the structural strength of the original material. This type of repair method can effectively repair wind turbine blades, but it has the disadvantage of low efficiency. In special low-temperature scenarios, the poor processability of thermosetting resins can delay the repair progress. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings and disadvantages of the prior art and provide a method for preparing a wind turbine blade repair resin and a wind turbine blade repair method. The resin is initiated by a heat source or light source that meets preset conditions. Compared with the reaction of traditional epoxy thermosetting resin, the polymerization process of this resin relies entirely on the self-exothermic reaction of the monomer, requiring no external heating and having extremely low energy consumption. The curing reaction is fast, and the cured board has good performance. Using this resin can greatly improve the efficiency of blade repair work.

[0005] To achieve the above objectives, the technical solution provided by this invention is as follows: a method for preparing a wind turbine blade repair resin, wherein the wind turbine blade repair resin comprises the following components by mass percentage:

[0006] Bisphenol A type epoxy resin 10%-90%;

[0007] Diluent 10%-70%;

[0008] Initiator 1%-5%;

[0009] The diluent is an alicyclic epoxy diluent; the initiator is one or a combination of two of the following: a cationic initiator or a free radical initiator; after mixing, the mixed monomers are impregnated with the fabric and coated onto the damaged areas of the wind turbine blades. The polymerization reaction in the locally coated area is initiated using a heat source initiation, a light source initiation, or a laser beam initiation method, wherein the temperature for heat source initiation, light source initiation, or laser beam initiation is controlled within [T]. 引发剂, T 沸点Within the range of ), where T 引发剂 T is the decomposition temperature of the initiator. 沸点 The boiling point of the mixed monomers is the starting point of the polymerization reaction. After the polymerization reaction starts, the monomers themselves continue to release heat to maintain the reaction until the mixed monomers in all coated areas are converted into polymers. The overall cycle of the polymerization reaction is 15-60 minutes, and the system is completely cured.

[0010] Furthermore, the temperature range induced by the heat source is 30-80℃; the wavelength of the light source induced by the light source is 300-405nm, and the light source adopts ultraviolet light; the laser power range induced by the laser beam is 0.1mW-100W, and the laser spot diameter is 1μm-10mm.

[0011] Furthermore, the alicyclic epoxy diluent includes 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarbamate ECC, vinylcyclohexene diepoxide VCE, and bis(adipic) ester EHA.

[0012] Furthermore, the cationic initiator includes onium salt compounds and organometallic compounds; the onium salt compounds include diaryliodoonium salt compounds; and the organometallic compounds include ferrocene salt compounds.

[0013] Furthermore, the free radical initiator includes organic peroxides and azo compounds.

[0014] A method for repairing wind turbine blades, using a wind turbine blade repair resin prepared according to the above-described preparation method, includes the following steps:

[0015] S1. Pre-treatment of damaged areas of wind turbine blades, including cleaning, grinding, and washing;

[0016] S2. Lay a fabric pre-impregnated with wind turbine blade repair resin flat on the damaged area of ​​the wind turbine blade;

[0017] S3. Short-term localized power supply triggers a polymerization reaction in the resin used for wind turbine blade maintenance, including:

[0018] A localized area of ​​the wind turbine blade repair resin coated or filled on the damaged part of the wind turbine blade is selected as the initial reaction area. An energy supply device is used to provide short-term energy to this initial reaction area; the energy supply method includes light source power, laser beam power, or heat source power, and the power supply temperature is controlled within [T]. 引发剂, T 沸点 Within the range of ), where T 引发剂 T is the decomposition temperature of the initiator. 沸点 The boiling point of the resin used for wind turbine blade maintenance is determined by the decomposition of the initiator to generate free radicals, which initiate the polymerization reaction of the resin monomers in the initial reaction region and release the heat of polymerization.

[0019] S4. The self-propagating polymerization reaction completes the overall curing, including:

[0020] The heat of polymerization released in the initial reaction region diffuses to the surrounding unreacted regions through heat conduction. When the temperature of the unreacted regions reaches T... 引发剂 At that time, the resin in the area is initiated to polymerize and release heat. The heat continues to spread until all the coated or filled wind turbine blade repair resin has completed the polymerization reaction, converting all the monomers into polymers, and realizing the overall curing of the wind turbine blade repair resin and the damaged parts of the wind turbine blade.

[0021] S5. Use sandpaper to polish the resin-cured area of ​​the wind turbine blade to make the surface of the resin-cured area consistent with the original surface of the wind turbine blade, thus completing the wind turbine blade repair.

[0022] Furthermore, step S1 includes:

[0023] First, clean the damaged areas of the wind turbine blades. Depending on the type of damage, use sandpaper, angle cutter, or grinding wheel to process the damaged areas into regular repair bevels. Finally, wipe away any debris from the repair bevels with a dry or damp cloth. If there are deep cracks in the damaged areas of the wind turbine blades, the damaged areas need to be ground down to the depth where the deep cracks appear before further treatment.

[0024] Furthermore, step S3 includes:

[0025] The power supply device includes a laser source, an ultraviolet light source, a hot air gun, and an infrared heating lamp.

[0026] A wind turbine blade repair resin is prepared based on the above preparation method.

[0027] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0028] 1. Significantly reduced energy consumption: The polymerization reaction only requires an initial heat source or light source to start, and no external heating is required afterwards. Compared with traditional epoxy thermosetting resins, energy consumption is reduced by more than 80%, making it energy-saving and environmentally friendly.

[0029] 2. Fast curing speed: The cycle from the start of the polymerization reaction to the complete curing of the system is 15-60 minutes, which is only 1 / 10-1 / 5 of the curing cycle of traditional epoxy thermosetting resin, greatly shortening the construction cycle of blade maintenance;

[0030] 3. Excellent performance after curing: The cured resin board for wind turbine blade repair has stable mechanical properties, with tensile strength ≥55MPa, flexural strength ≥90MPa, and D-type Shore hardness ≥85, meeting the requirements of blade repair for material strength, wear resistance and environmental aging resistance.

[0031] 4. Improved ease of construction: The wind turbine blade resin described in this invention does not crystallize or become unmixable at low temperatures, and its wettability with fabrics is significantly better than that of traditional repair resins, reducing the difficulty of construction.

[0032] 5. Wide adaptability: The viscosity of the resin system can be flexibly adjusted by adjusting the diluent ratio, making it suitable for various blade repair and construction processes such as coating, potting, and bonding, and applicable to the repair of blades of different types and degrees of damage. Attached Figure Description

[0033] Figure 1 This is a flowchart of wind turbine blade maintenance methods. Detailed Implementation

[0034] The present invention will be further described below with reference to several specific embodiments.

[0035] Example 1

[0036] The wind turbine blade repair resin provided in this embodiment is prepared from the following components by weight percentage:

[0037] Bisphenol A type epoxy resin – 50%;

[0038] Diluent: 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate (ECC) – 48%;

[0039] Initiator: Hexafluoroantimonate – 2%.

[0040] Initiation method: Light source initiation, using ultraviolet light with a wavelength of 405nm to irradiate the initial reaction region for 8 minutes to start the polymerization reaction; the system itself exothermics the temperature to rise to 70℃, and completes curing in 20 minutes.

[0041] The properties of fiberglass reinforced plastic (FRP) after curing when combined with biaxially oriented warp-knitted fabric are: tensile strength 158 MPa, compressive strength 137 MPa, interlaminar shear strength 34 MPa, and V-shear strength 205 MPa.

[0042] The process of wind turbine blade repair based on wind turbine blade repair resin is as follows: Figure 1 As shown, it includes the following steps:

[0043] S1. Pre-treatment of damaged areas on wind turbine blades: First, the damaged areas are cleaned. Depending on the type of damage, sandpaper, angle cutter, or grinding wheel dressing are used to create a regular repair bevel. Finally, a dry or damp cloth is used to wipe away debris from the repair bevel, ensuring a clean and smooth surface. If deep cracks exist in the damaged areas, the damaged areas must be ground down to the depth of the cracks before further treatment.

[0044] S2. Lay a fabric pre-impregnated with wind turbine blade repair resin on the damaged area of ​​the wind turbine blade.

[0045] S3. Short-term localized power supply triggers a polymerization reaction in the resin used for wind turbine blade maintenance, including:

[0046] A localized area of ​​the repair resin coated or filled onto the damaged part of the wind turbine blade is selected as the initial reaction zone. A power supply device is used to provide short-term energy to this initial reaction zone. This device includes a laser source, an ultraviolet light source, a hot air gun, and an infrared heating lamp. The power supply device is a small-scale device, suitable for complex working environments such as high altitudes and outdoor locations, reducing construction complexity and labor intensity. The energy supply time is determined based on the characteristics of the resin system and the size of the damaged part of the wind turbine blade. Energy is supplied via a light source, and the energy supply temperature is controlled within [T]. 引发剂, T 沸点 Within the range of ), where T 引发剂 T is the decomposition temperature of the initiator. 沸点 The boiling point of the mixed monomers is determined by the decomposition of the initiator to generate free radicals, which initiate the polymerization reaction of the monomers in the initial region of the reaction and release the heat of polymerization.

[0047] S4. The self-propagating polymerization reaction completes the overall curing, including:

[0048] The heat of polymerization released in the initial reaction region diffuses to the surrounding unreacted regions through heat conduction. When the temperature of the unreacted regions reaches T... 引发剂 At this time, the resin in the area is initiated to polymerize and release heat. The heat continues to spread, and the resin in the unreacted area is continuously initiated to polymerize, forming a self-propagating reaction. The entire self-propagating reaction process does not require continuous external energy supply and is maintained entirely by the heat released from the reaction of the resin system itself until all the coated or filled wind turbine blade repair resin has completed the polymerization reaction, converting all the monomers into polymers, and realizing the overall curing of the wind turbine blade repair resin and the damaged parts of the wind turbine blade.

[0049] S5. Use sandpaper to rough and then finely grind the resin-cured area of ​​the wind turbine blade to make the surface smoothness of the resin-cured area consistent with the original surface of the wind turbine blade. If appearance requirements need to be met, use paint that matches the color of the original coating of the wind turbine blade for coating. After coating, dry the coating according to its characteristics to finally complete the wind turbine blade repair.

[0050] Example 2

[0051] Unlike Example 1, the wind turbine blade repair resin provided in this example is prepared from the following components by weight percentage:

[0052] Bisphenol A type epoxy resin – 20%;

[0053] Diluent: Vinylcyclohexene diester (VCE) – 78%;

[0054] Initiator: Hexafluorophosphate – 2%.

[0055] Initiation method: Laser initiation. The initial reaction area is irradiated with a laser beam for 10 seconds to activate the reaction. The laser power is set to 50W and the spot diameter is 3mm. After the polymerization reaction starts, the system itself releases heat, raising the temperature to 150℃. After maintaining this temperature for 10 minutes, the system is completely cured.

[0056] The properties of fiberglass reinforced plastic (FRP) after curing when combined with biaxially oriented warp-knitted fabric are: tensile strength 155 MPa, compressive strength 145 MPa, interlaminar shear strength 32 MPa, and V-shear strength 200 MPa.

[0057] Example 3

[0058] Unlike Example 1, the wind turbine blade repair resin provided in this example is prepared from the following components by weight percentage:

[0059] Bisphenol A type epoxy resin – 80%;

[0060] Diluent: Bis(3,4-epoxycyclohexyl) adipate EHA – 15%;

[0061] Initiator: Benzoyl peroxide – 5%.

[0062] Initiation method: Heat source initiation, with an initial heat source temperature of 60℃. The polymerization reaction is initiated by heating the initial reaction area for 15 minutes; the system itself releases heat to raise the temperature to 80℃ and maintains it for 30 minutes to complete the curing.

[0063] The properties of fiberglass reinforced plastic (FRP) after curing when combined with biaxially oriented warp-knitted fabric are: tensile strength 162 MPa, compressive strength 140 MPa, interlaminar shear strength 35 MPa, and V-notch shear strength 208 MPa.

[0064] Examples 1 to 3 above all demonstrate the technical effects of the resin system of the present invention, which does not require continuous external heating, has a fast curing speed, and achieves the required performance after curing. Moreover, the construction process is simple and can effectively improve the maintenance efficiency of wind turbine blades.

[0065] Example 4

[0066] Unlike Examples 1-3, this example uses existing technology to prepare resin materials for repairing wind turbine blades, serving as a control.

[0067] Component A: 80-95% bisphenol A type epoxy resin, 5-20% elastomer-terminated epoxy polyether.

[0068] Component B: Alicyclic amines 10-24%, aromatic amines 30-47%, phenolic resin 11-30%, benzyl alcohol 8-20%, aminosilane coupling agent 0.1-1%.

[0069] The ratio of components A and B is 100:20 to 100:40 by weight.

[0070] Initiation method: Initiated by a heat source at a temperature of 70°C, curing is completed after heating for 7 hours.

[0071] The properties of fiberglass reinforced plastic (FRP) after curing when combined with biaxial warp-knitted fabric are: tensile strength 135 MPa, compressive strength 130 MPa, interlaminar shear strength 34 MPa, and V-shear strength 210 MPa.

[0072] Implementation Results

[0073] The wind turbine blade resin materials obtained in Examples 1-4 were combined with biaxial warp-knitted fabric to form fiberglass and cured. The fiberglass was then cut into standard test strips by a data machine tool and subjected to tensile, compressive and shear strength tests.

[0074] The test results are compared and analyzed in Table 1 below.

[0075] Table 1 Comparison of the properties of fiberglass formed by different curing methods in the comparative examples and embodiments.

[0076]

[0077] Examples 1, 2, and 3 respectively demonstrate the properties of fiberglass reinforced plastics (FRPs) prepared by ultraviolet light initiation, laser beam initiation, and heat source initiation. Compared with Example 4, Examples 1, 2, and 3 show that while significantly reducing the curing time, their mechanical properties did not decrease significantly. On the contrary, properties such as tensile strength and compressive strength were improved. Therefore, the resin system proposed in this invention can significantly reduce curing time without compromising mechanical properties, and has promising applications in the field of wind turbine blade maintenance.

[0078] The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Therefore, any changes made in accordance with the shape and principle of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for preparing a resin for wind turbine blade maintenance, characterized in that, The wind turbine blade repair resin comprises the following components by weight percentage: Bisphenol A type epoxy resin 10%-90%; Diluent 10%-70%; Initiator 1%-5%; The diluent is an alicyclic epoxy diluent; the initiator is one or a combination of two of the following: a cationic initiator or a free radical initiator; after mixing, the mixed monomers are impregnated with the fabric and coated onto the damaged areas of the wind turbine blades. The polymerization reaction in the locally coated area is initiated using a heat source initiation, a light source initiation, or a laser beam initiation method, wherein the temperature for heat source initiation, light source initiation, or laser beam initiation is controlled within [T]. 引发剂, T 沸点 Within the range of ), where T 引发剂 T is the decomposition temperature of the initiator. 沸点 The boiling point of the mixed monomers is the starting point of the polymerization reaction. After the polymerization reaction starts, the monomers themselves continue to release heat to maintain the reaction until the mixed monomers in all coated areas are converted into polymers. The overall cycle of the polymerization reaction is 15-60 minutes, and the system is completely cured.

2. The method for preparing a wind turbine blade maintenance resin according to claim 1, characterized in that, The temperature range induced by the heat source is 30-80℃; the wavelength of the light source induced by the light source is 300-405nm, and the light source is ultraviolet light; the laser power range induced by the laser beam is 0.1mW-100W, and the laser spot diameter is 1μm-10mm.

3. The method for preparing a wind turbine blade maintenance resin according to claim 1, characterized in that, The alicyclic epoxy diluents include 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarbamate (ECC), vinylcyclohexene diester (VCE), and bis(adipic) ester (EHA).

4. The method for preparing a wind turbine blade maintenance resin according to claim 1, characterized in that, The cationic initiator includes onium salts and organometallic compounds; the onium salts include diaryliodoonium salts; and the organometallic compounds include ferrocene salts.

5. The method for preparing a wind turbine blade maintenance resin according to claim 1, characterized in that, The free radical initiators include organic peroxides and azo compounds.

6. A method for maintaining wind turbine blades, characterized in that, The wind turbine blade repair resin prepared by the preparation method according to claim 1 is used to repair wind turbine blades, including the following steps: S1. Pre-treatment of damaged areas of wind turbine blades, including cleaning, grinding and washing; S2. Lay a fabric pre-impregnated with wind turbine blade repair resin flat on the damaged area of ​​the wind turbine blade; S3. Short-term localized power supply triggers a polymerization reaction in the resin used for wind turbine blade maintenance, including: A localized area of ​​the wind turbine blade repair resin coated or filled on the damaged part of the wind turbine blade is selected as the initial reaction area. An energy supply device is used to provide short-term energy to this initial reaction area; the energy supply method includes light source power, laser beam power, or heat source power, and the power supply temperature is controlled within [T]. 引发剂, T 沸点 Within the range of ), where T 引发剂 T is the decomposition temperature of the initiator. 沸点 The boiling point of the resin used for wind turbine blade maintenance is determined by the decomposition of the initiator to generate free radicals, which initiate the polymerization reaction of the resin monomers in the initial reaction region and release the heat of polymerization. S4. The self-propagating polymerization reaction completes the overall curing, including: The heat of polymerization released in the initial reaction region diffuses to the surrounding unreacted regions through heat conduction. When the temperature of the unreacted regions reaches T... 引发剂 At that time, the resin in the area is initiated to polymerize and release heat. The heat continues to spread until all the coated or filled wind turbine blade repair resin has completed the polymerization reaction, converting all the monomers into polymers, and realizing the overall curing of the wind turbine blade repair resin and the damaged parts of the wind turbine blade. S5. Use sandpaper to polish the resin-cured area of ​​the wind turbine blade to make the surface of the resin-cured area consistent with the original surface of the wind turbine blade, thus completing the wind turbine blade repair.

7. A method for maintaining wind turbine blades according to claim 6, characterized in that, Step S1 includes: First, clean the damaged areas of the wind turbine blades. Depending on the type of damage, use sandpaper, angle cutter, or grinding wheel to process the damaged areas into regular repair bevels. Finally, wipe away any debris from the repair bevels with a dry or damp cloth. If there are deep cracks in the damaged areas of the wind turbine blades, the damaged areas need to be ground down to the depth where the deep cracks appear before further treatment.

8. A method for maintaining wind turbine blades according to claim 6, characterized in that, Step S3 includes: the power supply device includes a laser source, an ultraviolet light source, a hot air gun, and an infrared heating lamp.

9. A resin for wind turbine blade maintenance, characterized in that, Prepared according to the preparation method described in any one of claims 1-5.

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