Aramid fiber prepreg material insulating rod for high-voltage drawout rod and preparation method thereof

Abstract

The application relates to the technical field of power equipment, in particular to an aramid prepreg material quality insulating rod for a high-voltage pull-out lever and a preparation method, the preparation method is as follows: S1, aramid prepreg preparation: selecting continuous aramid fiber cloth as a reinforcing body, impregnating the reinforcing body in a resin matrix system containing epoxy resin, nano silicon dioxide, an anti-aging agent and a silane coupling agent to obtain aramid prepreg; S2, mold layering: laying the aramid prepreg on a conical core mold; S3, curing and demolding: curing the core mold with the layered aramid prepreg, and demolding to obtain a hollow circular truncated cone pipe material after curing; performing surface treatment on the pipe material, and assembling multiple pipe materials according to length requirements to obtain the aramid prepreg material quality insulating rod for the high-voltage pull-out lever. The insulating rod is more lightweight, has better dynamic stiffness, can inhibit operation flutter, has better weather resistance and durability, and thus the operation safety and precision are improved.

Description

Technical Field

[0001] This invention relates to an insulating rod made of aramid prepreg material for high-voltage switching rods and its preparation method, belonging to the field of power equipment technology. Background Technology

[0002] In the operation and maintenance of power systems, high-voltage switch rods are key insulating tools used to operate high-voltage disconnect switches, drop-out fuses, and other equipment. Currently, most high-voltage switch rods on the market are made of fiberglass (a composite of epoxy resin and glass fiber). For example, patent application CN104953510A discloses an insulating operating rod capable of measuring distance and height, with the rod body made of epoxy resin composite material wrapped with alkali-free glass fiber material under pressure; patent application CN107838882A discloses a multi-section insulating rod, where the insulating rod is a glass fiber tube. These traditional switch rods have many obvious defects and urgently need improvement.

[0003] From a mechanical properties perspective, glass fiber has a high density, reaching 2.4-2.7 g / cm³. 3 This results in an excessively heavy overall weight for the switch arm. Taking a standard 5-meter-long fiberglass switch arm for 10kV as an example, its weight can reach 4-7 kg. In actual power operations, operators are prone to fatigue from prolonged hand-held operation, which not only reduces work efficiency but also poses a threat to operational safety, with a risk of operational errors due to physical exhaustion. Furthermore, the fiberglass material itself lacks sufficient dynamic stiffness, making the switch arm highly susceptible to chattering under stress. This chattering is particularly problematic during delicate operations such as aligning high-voltage contacts, severely impacting operational accuracy and significantly increasing the likelihood of misoperation, potentially leading to power safety accidents.

[0004] In terms of electrical performance and durability, fiberglass has poor weather resistance. When exposed to complex outdoor environments for extended periods, its insulation properties and mechanical strength gradually deteriorate, failing to consistently meet the safety requirements of electrical operations. For example, under harsh conditions such as high humidity and high salt spray, the insulation resistance of fiberglass switch rods decreases significantly, and the mechanical structure may also experience a reduction in strength due to corrosion and other reasons.

[0005] From a manufacturing process perspective, the production process of traditional fiberglass pull rods is complex, involving multiple steps such as fiberglass pretreatment, resin impregnation, and curing. This not only results in a long processing cycle but also high production costs, which is not conducive to large-scale promotion and application.

[0006] In summary, existing fiberglass high-voltage switching arms suffer from problems such as excessive weight, susceptibility to operational flutter, poor weather resistance, and high production costs, making it difficult to meet the higher requirements for lightweight, stable, durable, and economical high-voltage switching arms as the power system evolves towards intelligence and efficiency. Therefore, there is an urgent need to develop switching arms with new structures and materials to solve the aforementioned technical problems. Summary of the Invention

[0007] This invention addresses the shortcomings of existing fiberglass switch rods, such as excessive weight and easy vibration during operation, by providing an aramid prepreg insulating rod for high-voltage switch rods and its preparation method. The high-voltage switch rod has low weight, high dynamic stiffness, improves operational safety and accuracy, and extends the service life of the switch rod.

[0008] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A method for preparing an aramid prepreg insulating rod for a high-voltage switch rod, wherein the preparation method is as follows:

[0009] S1. Preparation of aramid prepreg:

[0010] Continuous aramid fiber cloth was selected as the reinforcement, and the reinforcement was impregnated in a resin matrix system containing epoxy resin, nano silica, anti-aging agent and silane coupling agent to obtain aramid prepreg.

[0011] S2, Mold Layering:

[0012] The aramid prepreg is laid on the conical mandrel;

[0013] S3, Curing and Demolding:

[0014] The core mold of the layered aramid prepreg is cured. After curing, the core mold is demolded to obtain a hollow frustum tube. The tube is then surface-treated, and multiple sections of the tube are assembled according to the required length to obtain an aramid prepreg insulating rod for high-voltage switch rods.

[0015] Furthermore, based on weight percentage, the mass percentages of each material in the prepreg are as follows: aramid fiber cloth 65%-75%, resin matrix 25%-35%;

[0016] By weight, the resin matrix contains 85-90 parts epoxy resin, 5-8 parts nano silica, 1-3 parts anti-aging agent, and 2-4 parts silane coupling agent.

[0017] Furthermore, the outer surface of the core mold is chrome-plated, with a surface roughness Ra≤0.4μm.

[0018] Furthermore, in step S2, the total thickness of the layup is 1-2 mm.

[0019] Furthermore, in step S2, after the aramid prepreg is laid up, a release film is wrapped around the outermost layer of the layup, wherein the wrapping tension is 15-25N.

[0020] Furthermore, in step S3, the mandrel of the plywood aramid prepreg is cured and molded in a vertical position.

[0021] Furthermore, in step S3, during the curing process, the temperature is increased to 130-150℃ at a rate of 1-2℃ / min, held for 13-15min, and simultaneously a pressure of 0.5-1MPa is applied. The air is vented 3-5 times, then the pressure is increased to 5-7MPa, and the temperature and pressure are maintained for 2-4h. The temperature is then cooled to 35-40℃ at a rate of 1-2℃ / min to complete the curing process. Finally, the mold is demolded after cooling to room temperature in the furnace.

[0022] Furthermore, the upper end diameter of the hollow frustum tube is 25-30mm, the lower end diameter is 35-40mm, the height is 1.2-1.4m, and the inclination angle of the hollow frustum tube is 87°-89°.

[0023] Furthermore, the aramid fabric is aramid 1414 fabric with an areal density of 185-195 g / m2; the anti-aging agent is a hindered amine anti-aging agent.

[0024] The present invention also discloses an insulating rod made of aramid prepreg material for high-voltage switch rods, wherein the insulating rod is prepared according to the preparation method described in the present invention.

[0025] The beneficial effects of this invention are:

[0026] The insulating rod of the switch rod described in this invention uses lightweight and high-strength aramid prepreg, effectively reducing the weight of the switch rod; combined with the conical truncated tube structure design, it improves the dynamic stiffness of the insulating rod and suppresses operational chatter; moreover, the insulating rod has excellent weather resistance and durability, thereby improving operational safety and accuracy, reducing production costs, extending the service life of the switch rod, and adapting to the ever-evolving needs of the power industry.

[0027] Specifically, the insulating rod of this invention uses low-density aramid fabric and a hollow truncated cone structure design. High-voltage switching rods made using this insulating rod are 50%-60% lighter than fiberglass switching rods of the same specifications. For example, a 5-meter-long 10kV switching rod can weigh only 2-3 kg, significantly reducing the labor intensity of operators and improving work efficiency. Furthermore, the hollow truncated cone tube structure effectively improves the dynamic stiffness of the insulating rod. Actual testing has verified that its anti-flutter capability is improved compared to traditional cylindrical rods. During operation, the vibration amplitude of the insulating rod is reduced, enabling more precise operation, reducing the risk of misoperation, and providing superior operational stability, thus ensuring the safety of power operations. The aramid fiber reinforced composite material gives the switching rod extremely high mechanical strength and good weather resistance. Both tensile and flexural strength are improved compared to fiberglass. Simultaneously, the addition of nanoparticles and anti-aging agents extends its service life under harsh environments such as ultraviolet radiation and acid rain, reducing equipment replacement frequency and maintenance costs.

[0028] The preparation method described in this invention, through precise layup design, enables directional optimization of the composite material's properties, further enhancing the rod's fatigue resistance and environmental resistance. Simultaneously, the prepreg molding process effectively controls resin content, reduces internal defects, and improves product consistency. Attached Figure Description

[0029] Figure 1 This is a cross-sectional view of the hollow frustum tube described in this invention;

[0030] Figure 2 This is a schematic diagram of the structure of the insulating rod described in this invention. Detailed Implementation

[0031] The specific embodiments of the present invention will be described in detail below. The present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used is for describing particular embodiments only and is not intended to limit the invention.

[0033] A method for preparing an aramid prepreg insulating rod for high-voltage switch rods, wherein the preparation method comprises:

[0034] S1. Preparation of aramid prepreg:

[0035] Continuous aramid fiber cloth was selected as the reinforcement, and the reinforcement was impregnated in a resin matrix system containing epoxy resin, nano silica, anti-aging agent and silane coupling agent to obtain aramid prepreg.

[0036] S2, Mold Layering:

[0037] The aramid prepreg is laid on the conical mandrel;

[0038] S3, Curing and Demolding:

[0039] The core mold of the layered aramid prepreg is cured. After curing, the core mold is demolded to obtain a hollow frustum tube. The tube is then surface-treated, and multiple sections of the tube are assembled according to the required length to obtain an aramid prepreg insulating rod for high-voltage switch rods.

[0040] The structure of the hollow frustum tube is as follows: Figure 1 As shown, the insulating rod structure for high-voltage switch rods is obtained by assembling multiple sections of tubing according to the required length. Figure 2 As shown, the insulating rod adopts a segmented design, with each segment connected by connectors (for example, carbon fiber connectors are used in this embodiment). The form of the connectors is not strictly limited, as long as a firm connection between the segments can be achieved (connectors commonly used in high-voltage switch rods can be used directly). Sealing rubber rings can be installed between each segment of the tube and the connectors to ensure a tight connection and waterproof and dustproof performance. The operating end of the insulating rod is equipped with a non-slip grip with a non-slip textured surface and an embedded shock-absorbing rubber layer; the working end can be detachably installed with different types of operating heads (such as hook-shaped or fork-shaped) according to usage requirements.

[0041] Specifically, by weight percentage, the mass percentages of each material in the prepreg are as follows: aramid fiber cloth 65%-75%, resin matrix 25%-35%; the resin matrix content in the prepreg is adjusted by controlling the impregnation time, and the impregnation time of the fiber in the impregnation tank is controlled by adjusting the roller speed of the impregnation roller, thereby controlling the resin matrix content in the prepreg.

[0042] By weight, the resin matrix contains 85-90 parts epoxy resin, 5-8 parts nano silica, 1-3 parts anti-aging agent, and 2-4 parts silane coupling agent.

[0043] More specifically, the specific process for preparing the resin matrix is ​​as follows: epoxy resin, nano silica particles, anti-aging agent, and silane coupling agent are added to the reactor in proportion, and stirred at 150-250 r / min for 1-2 hours at 60-80℃ until uniformly mixed to obtain the resin matrix.

[0044] Specifically, the outer surface of the core mold is chrome-plated with a surface roughness Ra≤0.4μm to ensure smooth demolding.

[0045] Specifically, in step S2, the total thickness of the layup is 1-2 mm.

[0046] Specifically, in step S2, after the aramid prepreg is laid up, a release film is wrapped around the outermost layer of the layup, wherein the wrapping tension is 15-25N.

[0047] Specifically, in step S3, the mandrel of the plywood aramid prepreg is placed vertically into the curing oven for curing and molding.

[0048] Specifically, in step S3, during the curing process, the temperature is increased to 130-150℃ at a rate of 1-2℃ / min, held for 13-15min, and simultaneously a pressure of 0.5-1MPa is applied. The air is vented 3-5 times, then the pressure is increased to 5-7MPa, and the temperature and pressure are maintained for 2-4h. The temperature is then cooled to 35-40℃ at a rate of 1-2℃ / min to complete the curing process. Finally, the material is demolded after cooling to room temperature in the furnace.

[0049] More specifically, in step S3, the hollow frustum tube obtained by demolding is subjected to surface grinding and polishing to remove burrs; the various sections of the tube are assembled into a complete insulating rod through high-strength connectors, and the operating end handle and working end operating head are installed to obtain the high-voltage switch rod.

[0050] Specifically, the hollow frustum tube has an upper diameter of 25-30mm, a lower diameter of 35-40mm, and a height of 1.2-1.4m. The inclination angle (the angle between the side generatrix and the bottom surface) of the hollow frustum tube is 87°-89°. This hollow frustum tube structure optimizes the stress distribution under load, increasing the moment of inertia of the cross-section by 20%-30% compared to traditional cylindrical rods, significantly improving bending and flutter resistance. Simultaneously, the hollow design further reduces weight, resulting in even greater weight reduction compared to solid structures.

[0051] Specifically, the aramid fabric is aramid 1414 fabric with an areal density of 185-195 g / m³. 2 The anti-aging agent is a hindered amine anti-aging agent.

[0052] More specifically, in this embodiment of the invention, the aramid fabric is aramid 1414 fabric, specifically model TH6108; its areal density is 205 g / m². 2 .

[0053] More specifically, the epoxy resin used in the embodiments of the present invention is model 315K, purchased from Weihai Guangxuan New Materials Co., Ltd.; the silane coupling agent used in the embodiments of the present invention is KH-602, purchased from Anhui Sibao; and the hindered amine anti-aging agent used in the embodiments of the present invention is N-ethylethylenediamine, purchased from Maclean.

[0054] The present invention also discloses an insulating rod made of aramid prepreg material for high-voltage switch rods, wherein the insulating rod is prepared according to the preparation method described in the present invention.

[0055] Example 1

[0056] Preparation of an aramid prepreg insulating rod for high-voltage switch rods:

[0057] S1. Prepreg preparation:

[0058] With a surface density of 205 g / m 2 Aramid 1414 fiber cloth is impregnated in a resin matrix system to produce a prepreg with a resin matrix content of 30%.

[0059] The resin matrix contains, by weight, 88 parts epoxy resin, 6 parts nano silica, 2 parts hindered amine anti-aging agent and 4 parts silane coupling agent.

[0060] S2, Mold Layering:

[0061] The aramid prepreg is laid on a conical mandrel, with a total layup thickness of 1-2 mm. After the aramid prepreg is laid up, a release film is wrapped around the outermost layer of the layup, with a wrapping tension of 20 N.

[0062] S3, Curing and Demolding:

[0063] The mandrel of the layered aramid prepreg was cured and molded in a vertical position. The specific conditions for the curing process were as follows: the temperature was increased to 150°C at a rate of 2°C / min, held for 13 min, and a pressure of 0.5 MPa was applied simultaneously. The pressure was vented 4 times, then the pressure was increased to 6 MPa, and the temperature and pressure were held for 2 h. The temperature was then cooled to 40°C at a rate of 2°C / min to complete the curing process. Finally, the material was cooled to room temperature in the furnace and demolded to obtain a hollow frustum tube with a lower outer diameter of 38 mm, an upper outer diameter of 28 mm, and a height of 1.3 m.

[0064] The hollow frustum tubes obtained after demolding are ground and polished to remove burrs; the four sections of hollow frustum tubes are assembled into a complete insulating rod (the thicker end is the operating end and the thinner end is the working end) using high-strength connectors; the operating end handle and the working end operating head are installed to obtain the high-voltage switch rod.

[0065] Example 2

[0066] Preparation of an aramid prepreg insulating rod for high-voltage switch rods:

[0067] S1. Prepreg preparation:

[0068] With a surface density of 205 g / m 2 Aramid 1414 fiber cloth is impregnated in a resin matrix system to produce a prepreg with a resin matrix content of 25%.

[0069] The resin matrix contains, by weight, 85 parts epoxy resin, 8 parts nano silica, 3 parts hindered amine anti-aging agent and 4 parts silane coupling agent.

[0070] S2, Mold Layering:

[0071] The aramid prepreg is laid on a conical mandrel, with a total layup thickness of 1-2 mm. After the aramid prepreg is laid up, a release film is wrapped around the outermost layer of the layup, with a wrapping tension of 15 N.

[0072] S3, Curing and Demolding:

[0073] The mandrel of the layered aramid prepreg was cured and molded in a vertical position. The specific conditions for the curing process were as follows: the temperature was increased to 130°C at a rate of 1°C / min, held for 15 min, and a pressure of 1 MPa was applied simultaneously. The pressure was vented 5 times, then the pressure was increased to 5 MPa, and the temperature and pressure were maintained for 4 h. The temperature was then cooled to 35°C at a rate of 1°C / min to complete the curing process. Finally, the material was cooled to room temperature in the furnace and demolded to obtain a hollow frustum tube with a lower outer diameter of 35 mm, an upper outer diameter of 25 mm, and a height of 1.2 m.

[0074] The hollow frustum tubes obtained after demolding are ground and polished to remove burrs; the four sections of hollow frustum tubes are assembled into a complete insulating rod (the thicker end is the operating end and the thinner end is the working end) using high-strength connectors; the operating end handle and the working end operating head are installed to obtain the high-voltage switch rod.

[0075] Example 3

[0076] Preparation of an aramid prepreg insulating rod for high-voltage switch rods:

[0077] S1. Prepreg preparation:

[0078] With a surface density of 205 g / m 2 Aramid 1414 fiber cloth is impregnated in a resin matrix system to produce a prepreg with a resin matrix content of 35%.

[0079] The resin matrix contains, by weight, 90 parts epoxy resin, 5 parts nano silica, 1 part hindered amine anti-aging agent and 4 parts silane coupling agent.

[0080] S2, Mold Layering:

[0081] The aramid prepreg is laid on a conical mandrel, with a total layup thickness of 1-2 mm. After the aramid prepreg is laid up, a release film is wrapped around the outermost layer of the layup, with a wrapping tension of 25 N.

[0082] S3, Curing and Demolding:

[0083] The mandrel of the layered aramid prepreg was cured and molded in a vertical position. The specific conditions for the curing process were as follows: the temperature was increased to 140℃ at a rate of 2℃ / min, held for 15min, and a pressure of 1MPa was applied simultaneously. The pressure was vented 4 times, then the pressure was increased to 7MPa, and the temperature and pressure were held for 3h. The temperature was then cooled to 40℃ at a rate of 2℃ / min to complete the curing process. Finally, the material was cooled to room temperature in the furnace and demolded to obtain a hollow frustum tube with a lower outer diameter of 40mm, an upper outer diameter of 35mm, and a height of 1.4m.

[0084] The hollow frustum tubes obtained after demolding are ground and polished to remove burrs; the four sections of hollow frustum tubes are assembled into a complete insulating rod (the thicker end is the operating end and the thinner end is the working end) using high-strength connectors; the operating end handle and the working end operating head are installed to obtain the high-voltage switch rod.

[0085] Comparative Example 1

[0086] Hollow frustum tubes and insulating rods were prepared using the same method as in Example 1, except that the resin matrix content in the prepreg of Comparative Example 1 was 40% (higher than the resin matrix content specified in this invention).

[0087] The other preparation process is exactly the same as in Example 1.

[0088] Comparative Example 2

[0089] The insulating rod was prepared using the same method as in Example 1, except that the insulating rod prepared in Comparative Example 2 was cylindrical. The specific preparation process is as follows:

[0090] S1. Prepreg preparation:

[0091] With a surface density of 205 g / m 2 Aramid 1414 fiber cloth is impregnated in a resin matrix system to produce a prepreg with a resin matrix content of 30%.

[0092] The resin matrix contains, by weight, 88 parts epoxy resin, 6 parts nano silica, 2 parts hindered amine anti-aging agent and 4 parts silane coupling agent.

[0093] S2, Mold Layering:

[0094] The aramid prepreg is laid on a cylindrical mandrel, with a total layup thickness of 1-2 mm. After the aramid prepreg is laid up, a release film is wrapped around the outermost layer of the layup, with a wrapping tension of 20 N.

[0095] S3, Curing and Demolding:

[0096] The mandrel of the layered aramid prepreg was cured and molded in a vertical position. The specific conditions for the curing process were as follows: the temperature was increased to 150°C at a rate of 2°C / min, held for 13 min, and a pressure of 0.5 MPa was applied simultaneously. The pressure was vented 4 times, then the pressure was increased to 6 MPa, and the temperature and pressure were held for 2 h. The temperature was then cooled to 40°C at a rate of 2°C / min to complete the curing process. Finally, the material was cooled to room temperature in the furnace and demolded to obtain a hollow cylindrical tube with an outer diameter of 33 mm and a height of 1.3 m.

[0097] The hollow cylindrical tubes obtained after demolding are ground and polished to remove burrs; the four hollow cylindrical tubes are assembled into a complete insulating rod (the thicker end is the operating end and the thinner end is the working end) using high-strength connectors; the operating end handle and the working end operating head are installed to obtain the high-voltage switch rod.

[0098] Comparative Example 3

[0099] The hollow frustum tube and insulating rod were prepared using the same method as in Example 1, except that the outer diameter of the working end was reduced in Comparative Example 3, resulting in an inclination angle (the angle between the side generatrix and the bottom surface) of 85° for the hollow frustum tube. The specific preparation process is as follows:

[0100] S1. Prepreg preparation:

[0101] With a surface density of 205 g / m 2 Aramid 1414 fiber cloth is impregnated in a resin matrix system to produce a prepreg with a resin matrix content of 30%.

[0102] The resin matrix contains, by weight, 88 parts epoxy resin, 6 parts nano silica, 2 parts hindered amine anti-aging agent and 4 parts silane coupling agent.

[0103] S2, Mold Layering:

[0104] The aramid prepreg is laid on a conical mandrel, with a total layup thickness of 1-2 mm. After the aramid prepreg is laid up, a release film is wrapped around the outermost layer of the layup, with a wrapping tension of 20 N.

[0105] S3, Curing and Demolding:

[0106] The mandrel of the layered aramid prepreg was cured and molded in a vertical position. The specific conditions for the curing process were as follows: the temperature was increased to 150°C at a rate of 2°C / min, held for 13 min, and a pressure of 0.5 MPa was applied simultaneously. The pressure was vented 4 times, then the pressure was increased to 6 MPa, and the temperature and pressure were maintained for 2 h. The temperature was then cooled to 40°C at a rate of 2°C / min to complete the curing process. Finally, the material was cooled to room temperature in the furnace and demolded to obtain a hollow frustum tube with a lower outer diameter of 38 mm, an upper outer diameter of 16 mm, and a height of 1.3 m.

[0107] The hollow frustum tubes obtained after demolding are ground and polished to remove burrs; the four sections of hollow frustum tubes are assembled into a complete insulating rod (the thicker end is the operating end and the thinner end is the working end) using high-strength connectors; the operating end handle and the working end operating head are installed to obtain the high-voltage switch rod.

[0108] Comparative Example 4

[0109] Hollow frustum tubes and insulating rods were prepared using the same method as in Example 1, except that: after the aramid prepreg in Comparative Example 4 was laid up, no release film was applied to the outermost layer of the layup; the other preparation methods were the same as in Example 1.

[0110] Comparative Example 5

[0111] Hollow frustum tubes and insulating rods were prepared using the same method as in Example 1, except that after the aramid prepreg in Comparative Example 5 was laid up, a release film was wrapped around the outermost layer of the layup with a wrapping tension of 35 N (higher than the wrapping tension specified in this invention). Other preparation methods were the same as in Example 1.

[0112] Comparative Example 6

[0113] Hollow frustum tubes and insulating rods were prepared using the same method as in Example 1, except that after the aramid prepreg in Comparative Example 6 was laid up, a release film was wrapped around the outermost layer of the layup with a wrapping tension of 10N (lower than the wrapping tension specified in this invention). Other preparation methods were the same as in Example 1.

[0114] Comparative Example 7

[0115] Hollow frustum tubes and insulating rods were prepared using the same method as in Example 1, except that in step S3 of Comparative Example 7, the mandrel of the layered aramid prepreg was cured and formed in a horizontal position. Other preparation methods were the same as in Example 1.

[0116] Comparative Example 8

[0117] Hollow frustum tubes and insulating rods were prepared using the same method as in Example 1, with the difference that in Comparative Example 5, aramid 1414 fiber woven fabric was replaced with glass fiber woven fabric, as detailed below:

[0118] Materials required: 7.0 kg of fiberglass woven fabric (brand name 5430), 2.5 kg of epoxy resin, 0.35 kg of silane coupling agent, 0.25 kg of nano silica particles, and 0.15 kg of hindered amine anti-aging agent.

[0119] The other preparation process is exactly the same as in Example 1.

[0120] The hollow frustum tubes and insulating rods prepared in the above embodiments and comparative examples were subjected to performance tests. The specific test results are shown in Table 1 below. The testing methods involved are as follows:

[0121] Mechanical performance testing methods: Bending tests are conducted using a universal testing machine; the operating conditions are simulated using a vibration testing bench to test the natural frequency of the hollow frustum tube, ensuring that it avoids the excitation frequency during operation and reducing flutter.

[0122] Electrical performance test: The hollow frustum tube was subjected to a power frequency withstand voltage test, and the leakage current was recorded at 100kV for 1 minute.

[0123] Flutter performance test: One end of the high-voltage switch rod was fixed using a vibration test bench, and the vibration was tested at 10 times / second with an acceleration of 10 m / s². 2 Test the conditions and record the swing amplitude of the other end of the lever.

[0124] Appearance quality inspection: Visually inspect the surface of the insulating rod; it should be smooth, flat, free of bubbles and cracks; measure the dimensions of each part to ensure they meet the design requirements.

[0125] Table 1 Performance Test Data

[0126]

[0127] As can be seen from the data in the table above, the insulating rods prepared by the method described in this invention in Examples 1-4 are lighter, effectively reducing the weight of the switch rod. At the same time, the insulating rods have better dynamic stiffness, suppressing operational chatter. Moreover, the insulating rods have better weather resistance and durability, thereby improving operational safety and accuracy, reducing production costs, extending the service life of the switch rods, and better adapting to the ever-evolving needs of the power industry.

[0128] A comparison of the experimental results of Comparative Example 1 and Example 1 shows that if the mass ratio of epoxy resin in the raw materials is increased during the preparation process, the weight of the pipe itself will increase, and the interlayer bonding performance will decrease due to the increase in resin content, resulting in a reduction in bending load.

[0129] A comparison of the experimental results of Comparative Example 2 and Example 1 shows that if the insulating rod is cylindrical, the pipe will be more prone to flutter, affecting daily use.

[0130] A comparison of the experimental results of Comparative Example 3 and Example 1 shows that if the tilt angle of the hollow frustum tube is reduced (i.e., the taper is increased), the bending load of the tube is reduced, and the working pressure resistance of the tube is reduced.

[0131] A comparison of the experimental results of Comparative Example 4 and Example 1 shows that if the release film is not applied, the appearance of the pipe will be rough and have burrs.

[0132] A comparison of the experimental results of Comparative Example 5 and Example 1 shows that if the covering tension is too high when covering the outermost layer of the prepreg with a release film, it will cause the prepreg to be squeezed and wrinkled, resulting in a poor surface morphology.

[0133] A comparison of the experimental results of Comparative Example 6 and Example 1 shows that if the release film is applied to the outermost layer of the prepreg, the covering tension will be too low, resulting in poor interfacial properties during prepreg curing and reduced mechanical properties and working pressure resistance of the pipe.

[0134] A comparison of the experimental results of Comparative Example 7 and Example 1 shows that if the mandrel of the plywood aramid prepreg is cured in a horizontal state, the prepreg will shift downward under the action of gravity, reducing the mechanical properties of the tube. However, curing it in a vertical state can produce an insulating rod with superior performance.

[0135] A comparison of the experimental results of Comparative Example 8 and Examples 1-4 shows that: compared with conventional glass fiber materials, the aramid prepreg used in this invention can significantly reduce the weight of the switch rod. Furthermore, due to the reduced weight of the aramid switch rod, its anti-flutter performance is superior to that of the glass fiber switch rod.

[0136] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0137] For those skilled in the art, various modifications and improvements can be made without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A method for preparing aramid prepreg material insulating pole for high voltage pole, characterized in that, The preparation method is: S1, aramid prepreg preparation: Select continuous aramid fiber cloth as a reinforcing body, and immerse the reinforcing body in a resin matrix system containing epoxy resin, nano silicon dioxide, anti-aging agent and silane coupling agent to obtain aramid prepreg; the model of the epoxy resin is 315K; S2, mold layering: Lay the aramid prepreg on the conical core mold; S3, curing and demolding: Cure the core mold of the layered aramid prepreg, and after curing, demold to obtain a hollow circular cone pipe; surface treatment is performed on the pipe, and according to the length requirement, multiple pipe sections are assembled to obtain an aramid prepreg material insulating rod for a high-voltage pullout lever; According to the weight percentage, the mass percentage of each material in the prepreg is: aramid fiber cloth 65%-75%, resin matrix 25%-35%; In step S2, after the aramid prepreg is layered, a release film is coated on the outermost layer of the layer, and the coating tension is 15-25N; The upper end face diameter of the hollow circular cone pipe is 25-30mm, the lower end face diameter is 35-40mm, the height is 1.2-1.4m, and the inclination angle of the hollow circular cone pipe is 87°-89°.

2. The method of claim 1, wherein the aramid prepreg material is a high pressure pole. According to the weight fraction, in the resin matrix, the epoxy resin is 85-90 parts, the nano silicon dioxide is 5-8 parts, the anti-aging agent is 1-3 parts, and the silane coupling agent is 2-4 parts.

3. The method of claim 1, wherein the aramid pre-preg material is a high pressure pole. The outer surface of the core mold is chrome plated, and the surface roughness Ra is ≤0.4μm.

4. The method of claim 1, wherein the aramid pre-preg material is a high pressure pole. The total thickness of the layer is 1-2mm.

5. The method of claim 1, wherein the aramid pre-preg material is a high pressure pole. In step S3, the core mold of the layered aramid prepreg is cured and formed in a vertical state.

6. The method of claim 1, wherein the aramid pre-preg material is a high pressure pole. In the curing and forming process in step S3, the temperature is raised at a rate of 1-2℃ / min to 130-150℃, and the pressure of 0.5-1MPa is applied for 13-15min, and the exhaust is 3-5 times, then the pressure is increased to 5-7MPa, and the temperature is kept for 2-4h, and the cooling rate is 1-2℃ / min to 35-40℃, and the curing and forming is completed; finally, the mold is demolded after cooling to room temperature.

7. The method of claim 1, wherein the aramid pre-preg material is a high pressure pole. The aramid fabric is aramid 1414 fabric having an areal density of 185-195 g / m 2 ; the anti-aging agent is a hindered amine-based anti-aging agent.

8. An aramid prepreg material pole for high voltage pole with drawout, characterized in that, The insulating rod is prepared by the preparation method according to any one of claims 1-7.

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