Graphite-based flexible grounding device

Abstract

The invention relates to the technical field of grounding protection devices, and discloses a graphite-based flexible grounding device, which comprises a graphite-based flexible connecting wire and a graphite-based flexible grounding wire, and the graphite-based flexible connecting wire and the graphite-based flexible grounding wire are connected together through a connecting clamp. The graphite-based flexible connecting wire and the graphite-based flexible grounding wire are both made of a graphite-based flexible material, and the graphite-based flexible material is prepared from the following raw materials in parts by weight: 90-95 parts of expanded graphite, 10-20 parts of glass fiber, 5-10 parts of a water-based pressure-sensitive adhesive, 5-8 parts of sorbitol monooleate, 6-10 parts of monopotassium phosphate, 0.5-2 parts of an antioxidant, 0.3-1.5 parts of an ultraviolet light absorber and 1-5 parts of an auxiliary substance; the auxiliary substance is used for improving the soil adaptability and comprises 2-5 parts of calcium carbonate, 1-3 parts of boric acid or 1-2 parts of monopotassium phosphate; the coating has the advantages of good corrosion resistance and weather resistance, long service life and stable and reliable performance.

Description

TECHNICAL FIELD

[0001] The present application relates to a graphite-based flexible grounding device, belonging to the technical field of grounding protection devices. BACKGROUND

[0002] The graphite-based flexible grounding device is mainly composed of graphite material, which is made by special process to have good electrical conductivity and flexibility. It is used to safely introduce the current generated by electrical equipment, buildings, etc. (such as lightning current, fault current, etc.) into the ground to protect the equipment and personnel safety.

[0003] At present, the common graphite-based flexible grounding device is mainly composed of the following structures: Graphite-based material: It is the main component of the grounding device, which is made of high-purity flake graphite and other materials through high-temperature puffing, pressing and other processes, and can provide a low-resistance conduction path for the current.

[0004] Reinforcing material: It is used to improve the mechanical strength and flexibility of the grounding device. Common reinforcing materials are glass fiber, polyester fiber, etc. It can be compounded with graphite-based material to form a whole structure, so that the grounding device can maintain stable performance in different environmental conditions.

[0005] Metal connecting piece: It is used to connect the grounding device with the electrical equipment that needs grounding. Common metal connecting pieces are copper bars, steel bolts, etc. Such connecting pieces have good electrical conductivity and corrosion resistance to ensure that the current can be smoothly conducted from the equipment to the grounding device.

[0006] Among them, the stability, electrical conductivity and corrosion resistance of graphite-based material are the key factors affecting whether the grounding device can operate stably for a long time. However, the corrosion resistance of common graphite-based materials is generally poor. Therefore, in the prior art, Chinese patent application No. CN202011623068.7 discloses a lightning protection grounding graphite-based flexible composite material for power transmission and transformation system, which uses expanded graphite as the main material, adds appropriate amount of glass fiber to enhance the mechanical properties and corrosion resistance, and adds appropriate amount of sorbitol monooleate and potassium dihydrogen phosphate to improve the corrosion resistance of the graphite composite material. The two work together as a corrosion inhibitor to delay the corrosion of the material, solving the problem of surface graphite falling off of the flexible graphite composite grounding material in long-term rain, sun exposure and other environments. However, there are still some problems in actual use: 1. Although it can solve the problem of surface graphite falling off, its corrosion resistance may still be insufficient in long-term complex natural and soil environments, such as long-term sun exposure.

[0007] 2. It does not provide specific adaptation improvement plans for different types of soil (such as acidic soil, alkaline soil, saline-alkali soil, etc.), which leads to significant differences in its service life and performance when applied to different soil environments. Summary of the Invention

[0008] To address the aforementioned problems in the existing technology, the present invention provides a graphite-based flexible grounding device.

[0009] The technical solution of the present invention is as follows: A graphite-based flexible grounding device includes a graphite-based flexible connecting wire for connecting electrical equipment requiring grounding and a graphite-based flexible grounding wire installed on the ground for grounding. The graphite-based flexible connecting wire and the graphite-based flexible grounding wire are connected together by a connecting clamp. Both the graphite-based flexible connecting wire and the graphite-based flexible grounding wire are made of graphite-based flexible material, which is composed of the following raw materials in parts by weight: 90-95 parts expanded graphite, 10-20 parts glass fiber, 5-10 parts water-based pressure-sensitive adhesive, 5-8 parts sorbitol monooleate, 6-10 parts potassium dihydrogen phosphate, 0.5-2 parts antioxidant, 0.3-1.5 parts ultraviolet absorber, and 1-5 parts auxiliary substances. The auxiliary substances are used to improve soil adaptability and are 2-5 parts calcium carbonate, 1-3 parts boric acid, or 1-2 parts potassium dihydrogen phosphate.

[0010] Furthermore, the graphite-based flexible connecting wire and the graphite-based flexible grounding wire form an L-shaped structure under the connection action of the connecting clamp. The end of the graphite-based flexible connecting wire away from the connecting clamp is provided with connecting hardware for connecting to electrical equipment that needs to be grounded. The segments of the graphite-based flexible connecting wire and the graphite-based flexible grounding wire close to the connecting clamp are both arc-shaped.

[0011] Furthermore, copper wires are provided inside both the graphite-based flexible connecting wire and the graphite-based flexible grounding wire. The copper wires are distributed in a ring array inside both the graphite-based flexible connecting wire and the graphite-based flexible grounding wire, and the center of the ring array is the center of both the graphite-based flexible connecting wire and the graphite-based flexible grounding wire.

[0012] Furthermore, the ratio of the diameter of the copper wire in the graphite-based flexible connecting wire to the diameter of the graphite-based flexible connecting wire is 1:5 to 10, and the ratio of the diameter of the copper wire in the graphite-based flexible grounding wire to the diameter of the graphite-based flexible connecting wire is also 1:5 to 10.

[0013] Furthermore, the ratio of the circular structure formed by the copper wire within the graphite-based flexible connecting wire to the diameter of the graphite-based flexible connecting wire is 0.4 to 0.65, and the ratio of the circular structure formed by the copper wire within the graphite-based flexible grounding wire to the diameter of the graphite-based flexible grounding wire is 0.4 to 0.65.

[0014] Further, the graphite-based flexible material is further composed of 0.1-0.5 parts of conductive fillers by weight.

[0015] Further, the expanded graphite has a particle size of 7-20 mu m, which is prepared from high-purity flake graphite by oxidation and high-temperature expansion in sequence, the oxidation is treated by high-chloric acid and potassium permanganate, the high-temperature expansion is to treat the oxidized high-purity flake graphite at 1000-1200 DEG C, and the density of the expanded graphite is 0.002-0.003 g / cm3.

[0016] Further, the glass fiber has a diameter of 9-15 mu m and a density of 2.5-3.0 g / cm3, the sorbitan monooleate has an acid value of 6-8 mgKOH / g, a hydroxyl value of 190-250 mgKOH / g, and a saponification value of 135-160 mgKOH / g.

[0017] Further, the preparation method of the graphite-based flexible material is to mix the expanded graphite, the glass fiber, the water-based pressure-sensitive adhesive, the sorbitan monooleate, the potassium dihydrogen phosphate, the antioxidant, the ultraviolet absorber and the auxiliary material, and to prepare the graphite-based flexible composite material through rolling, thermoplastic and stranding forming processes.

[0018] Further, the rolling temperature is 220-240 DEG C, the rolling pressure is 130-140 MPa, the rolling speed is 0.2-0.3 m / s, and the thermoplastic temperature is 260-280 DEG C.

[0019] The present application has the following advantages: The present application can further improve the corrosion resistance and weather resistance of the material by adopting the specific graphite-based flexible material to manufacture the graphite-based flexible connecting line and the graphite-based flexible grounding line, adding the antioxidant and the ultraviolet absorber into the graphite-based flexible material, preventing the material from oxidizing when exposed to air for a long time, delaying the performance degradation of the material, absorbing the ultraviolet rays to reduce the damage of the ultraviolet rays to the material and improve the stability of the material in the long-term exposure environment, adding the auxiliary material into the graphite-based flexible material, adding the calcium carbonate to neutralize the acidic components in the soil and reduce the corrosion rate of the material in the acidic soil, adding the boric acid to prevent the material from being alkali corroded in the alkaline soil, and increasing the amount of the potassium dihydrogen phosphate to increase the content of the salt corrosion resistant components in the material, so that the material has better salt corrosion resistance, and the service life and the performance stability and reliability of the grounding device can be ensured by selecting the corresponding material when used in different soil environments, and the present application has the advantages of good corrosion resistance and weather resistance, long service life and stable and reliable performance compared with the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1This is a schematic diagram of the structure of the present invention; Fig. 2 This is a cross-sectional view of the graphite-based flexible connecting wire in this invention; Fig. 3 This is a cross-sectional view of the graphite-based flexible grounding wire in this invention.

[0021] The reference numerals in the figure are as follows: 1. Graphite-based flexible connecting wire; 2. Graphite-based flexible grounding wire; 3. Connecting clamp; 4. Connecting hardware; 5. Copper wire. Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0023] Please refer to Figs. 1-3 This invention provides a graphite-based flexible grounding device, comprising a graphite-based flexible connecting wire 1 for connecting electrical equipment requiring grounding and a graphite-based flexible grounding wire 2 disposed on the ground for grounding. The graphite-based flexible connecting wire 1 and the graphite-based flexible grounding wire 2 are connected together by a connecting clamp 3, and the graphite-based flexible connecting wire 1 and the graphite-based flexible grounding wire 2 form an L-shaped structure under the connection action of the connecting clamp 3 so that they can adapt to the angle formed between the electrical equipment and the ground, thereby ensuring the grounding effect. A connecting hardware 4 for connecting to the electrical equipment requiring grounding is provided on the end of the graphite-based flexible connecting wire 1 away from the connecting clamp 3. The segments of the graphite-based flexible connecting wire 1 and the graphite-based flexible grounding wire 2 close to the connecting clamp 3 are both arc-shaped. The specific diameter of the arc structure can be selected and set according to the actual situation. The arc structure is set to leave a slack for expansion and contraction to facilitate subsequent adjustment work.

[0024] In use, the graphite-based flexible connecting wire 1 is connected to the electrical equipment to be grounded by means of connecting hardware 4. Then, the graphite-based flexible connecting wire 1 is connected to the graphite-based flexible grounding wire 2 by means of connecting clamp 3. Finally, the graphite-based flexible grounding wire 2 is placed on the ground for grounding to complete the installation and use.

[0025] Both the graphite-based flexible connecting wire 1 and the graphite-based flexible grounding wire 2 are made of graphite-based flexible material, which is composed of the following raw materials in parts by weight: 90-95 parts expanded graphite, 10-20 parts glass fiber, 5-10 parts water-based pressure-sensitive adhesive, 5-8 parts sorbitol monooleate, 6-10 parts potassium dihydrogen phosphate, 0.5-2 parts antioxidant, 0.3-1.5 parts ultraviolet absorber, and 1-5 parts auxiliary material. The auxiliary material is used to improve soil adaptability and consists of 2-5 parts calcium carbonate, 1-3 parts boric acid, or 1-2 parts potassium dihydrogen phosphate. When this grounding device is used on acidic soil, the auxiliary material is 2-5 parts calcium carbonate; when used on alkaline soil, the auxiliary material is 1-3 parts boric acid; and when used on saline-alkali soil, the auxiliary material is 1-2 parts potassium dihydrogen phosphate.

[0026] Compared with the invention patent with application number CN202011623068.7, this invention increases the number of expanded graphite components to form a denser and more continuous conductive network, so that lightning current and other currents can be conducted more smoothly in the material, and the grounding resistance of this graphite-based flexible material can be further reduced. By increasing the number of glass fibers, the tensile strength, flexural strength and impact resistance of this graphite-based flexible material can be significantly improved, making the grounding device less prone to breakage or deformation in complex installation and use environments, thereby ensuring the long-term stable operation of the grounding device. By reducing the amount of water-based pressure-sensitive adhesive, the internal pore structure of this graphite-based flexible material can be made more reasonable, and its flexibility can be enhanced, making it easier to install and lay in different terrains and environments. By increasing the amount of sorbitol monooleate, the expanded graphite and glass fiber components can be better dispersed, making them more evenly distributed in this graphite-based flexible material. This improves the overall consistency and stability of the performance of the graphite-based flexible material and avoids performance differences caused by uneven local composition. By increasing the amount of potassium dihydrogen phosphate, the graphite-based flexible material can be better protected from erosion by chemicals in the soil, thereby extending the service life of the grounding device. By adding antioxidants, the oxidation reaction of this graphite-based flexible material can be prevented when it is exposed to air for a long time, thereby delaying the degradation of the performance of this graphite-based flexible material. By adding a UV absorber, the UV absorber can absorb ultraviolet rays, reduce the damage of ultraviolet rays to the graphite-based flexible material, and improve the stability of the graphite-based flexible material under long-term exposure, thereby further improving the corrosion resistance and weather resistance of the graphite-based flexible material. By adding auxiliary substances, calcium carbonate can neutralize acidic components in the soil, reducing the corrosion rate of this graphite-based flexible material in acidic soils. The addition of boric acid can prevent alkaline corrosion in alkaline soils. Increasing the amount of potassium dihydrogen phosphate can increase the content of salt-resistant components in the graphite-based flexible material, thereby improving its salt-corrosion resistance. When applied to different soil environments, selecting appropriate auxiliary substances in the fabrication of this graphite-based flexible material can ensure the service life and performance stability and reliability of this grounding device.

[0027] The graphite-based flexible material also comprises the following raw materials in parts by weight: 0.1 to 0.5 parts conductive filler. By adding conductive filler, the conductivity and electromagnetic shielding performance of this graphite-based flexible material can be improved, thereby reducing the impact of electromagnetic interference on grounded electrical equipment.

[0028] The expanded graphite used in this invention has a particle size of 7-20 μm and is prepared by sequentially oxidizing and high-temperature expanding high-purity flake graphite. The oxidation is carried out by treating with perchloric acid and potassium permanganate, and the high-temperature expansion is carried out by treating the oxidized high-purity flake graphite at an environment of 1000-1200℃. The density of the expanded graphite is 0.002-0.003 g / cm³.

[0029] The glass fiber used in this invention has a diameter of 9–15 μm and a density of 2.5–3.0 g / cm³; the sorbitol monooleate used in this invention has an acid value of 6–8 mg KOH / g, a hydroxyl value of 190–250 mg KOH / g, and a saponification value of 135–160 mg KOH / g.

[0030] The antioxidants selected in this invention are hindered phenolic antioxidants, such as BHT and antioxidant 1010; the ultraviolet absorbers selected in this invention are benzotriazole ultraviolet absorbers, such as UV-P and UV-320.

[0031] The preparation method of this graphite-based flexible material is as follows: expanded graphite, glass fiber, water-based pressure-sensitive adhesive, sorbitan monooleate, potassium dihydrogen phosphate, antioxidant, ultraviolet absorber, and auxiliary substances are mixed, and the mixture is then processed through rolling, thermoplasticizing, and stranding to obtain the graphite-based flexible composite material. Specifically, the rolling temperature is 220–240℃, the rolling pressure is 130–140 MPa, the rolling speed is 0.2–0.3 m / s, and the thermoplasticizing temperature is 260–280℃.

[0032] Compared to the invention patent with application number CN202011623068.7, this invention, by increasing the rolling temperature, can adjust the crystallinity of the components in the graphite-based flexible material, making the crystallization more complete. This improves the hardness, strength, and wear resistance of the graphite-based flexible material, enabling it to better resist erosion and damage from the external environment during long-term use. By increasing the rolling pressure, the internal structure of this graphite-based flexible material can be made more compact. The higher density can reduce the scattering of electrons during conduction in this graphite-based flexible material, thereby reducing the resistance of this graphite-based flexible material. By reducing the roller speed, the raw materials have more time to mix and interact fully during the rolling process, allowing the components to be more evenly distributed in the graphite-based flexible material and avoiding localized unevenness.

[0033] By increasing the thermoplastic temperature, the molecular chains in this graphite-based flexible material can possess higher energy and more active movement. This allows for more stable entanglement and cross-linking reactions between molecular chains, thereby enhancing the strength and toughness of this graphite-based flexible material.

[0034] Both the graphite-based flexible connecting wire 1 and the graphite-based flexible grounding wire 2 contain copper wires 5. These copper wires 5 are arranged in a ring array within both wires, with the center of the ring array being the center of both wires. The number of copper wires 5 in each wire can range from 8 to 24, depending on the diameter of the graphite-based flexible connecting wire 1 and the graphite-based flexible grounding wire 2. The presence of copper wires 5 enhances the conductivity and overall mechanical strength of the graphite-based flexible connecting wire 1 and the graphite-based flexible grounding wire 2.

[0035] The diameter ratio of the copper wire 5 in the graphite-based flexible connecting wire 1 to the diameter of the graphite-based flexible connecting wire 1 is 1:5 to 10. The diameter ratio of the copper wire 5 in the graphite-based flexible grounding wire 2 to the diameter of the graphite-based flexible connecting wire 1 is also 1:5 to 10. Through the aforementioned arrangement, sufficient copper conductor area can be ensured to improve the conductivity of the circuit.

[0036] The ratio of the circular structure formed by the copper wire within the graphite-based flexible connecting wire 1 to the diameter of the graphite-based flexible connecting wire 1 is 0.4 to 0.65. Similarly, the ratio of the circular structure formed by the copper wire within the graphite-based flexible grounding wire 2 to the diameter of the graphite-based flexible grounding wire 2 is also 0.4 to 0.65. This configuration allows for a more uniform distribution of current across the cross-section of the grounding electrode, preventing excessive current concentration at the center or edges of the line and avoiding localized overheating and increased resistance caused by uneven current distribution.

[0037] Example 1: This example provides a graphite-based flexible material composed of the following parts by weight: 90 parts expanded graphite, 10 parts glass fiber, 5 parts water-based pressure-sensitive adhesive, 5 parts sorbitol monooleate, 6 parts potassium dihydrogen phosphate, 0.5 parts antioxidant, 0.3 parts ultraviolet absorber, 2 parts calcium carbonate, and 0.1 parts conductive filler.

[0038] The expanded graphite used in this embodiment has a particle size of 7μm. It is prepared by sequentially oxidizing and high-temperature expanding high-purity flake graphite. The oxidation is carried out by treating with perchloric acid and potassium permanganate. The high-temperature expansion is carried out by treating the oxidized high-purity flake graphite at 1000℃. The density of the expanded graphite is 0.002g / cm³.

[0039] The glass fiber used in this embodiment has a diameter of 9 μm and a density of 2.5 g / cm³; the sorbitol monooleate used in this embodiment has an acid value of 6 mg KOH / g, a hydroxyl value of 190 mg KOH / g, and a saponification value of 135 mg KOH / g.

[0040] The antioxidant used in this embodiment is antioxidant 1010, and the ultraviolet absorbers used in this embodiment are UV-P and UV-320.

[0041] The preparation method of this graphite-based flexible material is as follows: expanded graphite, glass fiber, water-based pressure-sensitive adhesive, sorbitol monooleate, potassium dihydrogen phosphate, antioxidant, ultraviolet absorber, and auxiliary substances are mixed, and the mixture is then processed through rolling, thermoplasticizing, and stranding to obtain the graphite-based flexible composite material. Specifically, the rolling temperature is 220℃, the rolling pressure is 130MPa, the rolling speed is 0.2m / s, and the thermoplasticizing temperature is 260℃.

[0042] Example 2: This example provides a graphite-based flexible material composed of the following parts by weight of raw materials: 95 parts expanded graphite, 20 parts glass fiber, 10 parts water-based pressure-sensitive adhesive, 8 parts sorbitol monooleate, 10 parts potassium dihydrogen phosphate, 2 parts antioxidant, 1.5 parts ultraviolet absorber, 5 parts calcium carbonate and 0.5 parts conductive filler.

[0043] The expanded graphite used in this embodiment has a particle size of 20 μm. It is prepared by sequentially oxidizing and high-temperature expanding high-purity flake graphite. The oxidation is carried out by treating with perchloric acid and potassium permanganate. The high-temperature expansion is carried out by treating the oxidized high-purity flake graphite at 1200℃. The density of the expanded graphite is 0.003 g / cm³.

[0044] The glass fiber used in this embodiment has a diameter of 15μm and a density of 3.0g / cm³; the sorbitol monooleate used in this embodiment has an acid value of 8mgKOH / g, a hydroxyl value of 250mgKOH / g, and a saponification value of 160mgKOH / g.

[0045] The antioxidant used in this embodiment is antioxidant 1010, and the ultraviolet absorbers used in this embodiment are UV-P and UV-320.

[0046] The preparation method of this graphite-based flexible material is as follows: expanded graphite, glass fiber, water-based pressure-sensitive adhesive, sorbitol monooleate, potassium dihydrogen phosphate, antioxidant, ultraviolet absorber, and auxiliary substances are mixed, and the mixture is then processed through rolling, thermoplasticizing, and stranding to obtain the graphite-based flexible composite material. Specifically, the rolling temperature is 240℃, the rolling pressure is 140MPa, the rolling speed is 0.3m / s, and the thermoplasticizing temperature is 280℃.

[0047] Example 3: This example provides a graphite-based flexible material, which differs from Example 1 in that 2 parts of calcium carbonate are replaced with 1 part of boric acid.

[0048] Example 4: This example provides a graphite-based flexible material, which differs from Example 2 in that: 3 parts of calcium carbonate are replaced with 3 parts of boric acid.

[0049] Example 5: This example provides a graphite-based flexible material, which differs from Example 1 in that 2 parts of calcium carbonate are replaced with 1 part of potassium dihydrogen phosphate.

[0050] Example 6: This example provides a graphite-based flexible material, which differs from Example 2 in that 2 parts of calcium carbonate are replaced with 2 parts of potassium dihydrogen phosphate.

[0051] Quality tests were conducted on the products from Examples 1 to 6.

[0052] 1. DC resistance test The DC resistance was measured using the double-arm bridge method, and the results are shown in the table below:

[0053] 2. Power frequency current withstand performance After conducting the power frequency current test, observe the product's appearance for defects such as broken strands, ablation, and bulging. The results are shown in the table below:

[0054] 3. Lightning current impulse withstand performance After conducting the 8 / 20μs, 50kA standard lightning current impulse withstand test, the product's appearance was observed for defects such as broken strands, ablation, and bulging, and whether the increase in DC resistance per unit length exceeded 10%. The results are shown in the table below:

[0055] 4. Bending, torsional and tensile strength properties The bending performance test was carried out with a bending radius not exceeding 30cm. After bending 90 degrees 10 times in each of the forward and reverse directions, the increase in DC resistance per unit length was measured to see if it exceeded 10%. Torsional resistance tests were conducted, and after torsion of 180 degrees / m, the increase in DC resistance per unit length was measured to see if it exceeded 10%. Tensile performance test: After applying a tensile force of 5000N and holding it for 10s, check whether the increase in DC resistance per unit length exceeds 10%; The specific results are shown in the table below:

[0056] 5. Corrosion resistance An alkaline corrosion test was conducted, in which the sample was immersed in a 5% NaOH solution at room temperature for 480 hours, and the increase in DC resistance per unit length was measured to see if it exceeded 10%. An acid corrosion test was conducted, in which the sample was immersed in a 5% H2SO4 solution at room temperature for 480 hours, and the increase in DC resistance per unit length was measured to see if it exceeded 10%. A salt water corrosion test was conducted. After immersing the sample in a 3.5% NaCl solution at room temperature for 720 hours, the increase in DC resistance per unit length was measured to see if it exceeded 10%. The specific results are shown in the table below:

[0057] Comparative Example 1: A graphite-based flexible composite material for lightning protection grounding in power transmission and transformation systems, made from the following raw materials in parts by weight: 80 parts expanded graphite, 12 parts glass fiber, 15 parts water-based pressure-sensitive adhesive, 5 parts sorbitol monooleate, and 3 parts potassium dihydrogen phosphate. The expanded graphite is prepared by sequentially oxidizing and high-temperature expanding high-purity flake graphite. Oxidation is performed using perchloric acid and potassium permanganate, while high-temperature expansion involves treating the oxidized high-purity flake graphite at 1000℃. The mass ratio of perchloric acid to potassium permanganate is 3.2:1. The graphite-based flexible composite material for lightning protection and grounding of power transmission and transformation systems is obtained by the following preparation method: expanded graphite, glass fiber, water-based pressure-sensitive adhesive, sorbitol monooleate and potassium dihydrogen phosphate are mixed and then processed by rolling, thermoplasticizing and stranding to obtain the graphite-based flexible composite material. The rolling temperature is 180℃, the pressure is 115MPa and the rolling speed is 0.4m / s; the thermoplasticizing temperature is 230℃.

[0058] Comparative Example 2: A graphite-based flexible composite material for lightning protection grounding in power transmission and transformation systems, made from the following raw materials in parts by weight: 75 parts expanded graphite, 10 parts glass fiber, 10 parts water-based pressure-sensitive adhesive, 3 parts sorbitol monooleate, and 1 part potassium dihydrogen phosphate. The expanded graphite is prepared by sequentially oxidizing and high-temperature expanding high-purity flake graphite. Oxidation is performed using perchloric acid and potassium permanganate, while high-temperature expansion involves treating the oxidized high-purity flake graphite at 1100℃. The mass ratio of perchloric acid to potassium permanganate is 2.5:1. The graphite-based flexible composite material for lightning protection and grounding of power transmission and transformation systems is obtained by the following preparation method: expanded graphite, glass fiber, water-based pressure-sensitive adhesive, sorbitol monooleate and potassium dihydrogen phosphate are mixed and then processed by rolling, thermoplasticizing and stranding to obtain the graphite-based flexible composite material. The rolling temperature is 150℃, the pressure is 110MPa and the rolling speed is 0.3m / s; the thermoplasticizing temperature is 210℃.

[0059] 1. Conduct an exposure test; Choose an open, unobstructed outdoor site, set up a sun exposure test rack, and fix the products of Examples 1-6 and Comparative Examples 1 and 2 on the test rack to ensure that the products are fully exposed to sunlight. The exposure time is 1 month.

[0060] In the initial stage of the experiment, the tensile strength and elongation of the products from Examples 1-6 and Comparative Examples 1 and 2 were measured using a tensile testing machine. After the exposure was completed, the tensile strength and elongation of the products from Examples 1-6 and Comparative Examples 1 and 2 were measured using a tensile testing machine. The results are shown in the table below:

[0061] As can be seen from the data in the table above, under the same exposure time, the products of Examples 1 to 6 showed a significantly smaller decrease in tensile strength and elongation at break compared to the products of Comparative Example 1 and Comparative Example 2. This indicates that the products of Examples 1 to 6 have better corrosion resistance and weather resistance under exposure conditions.

[0062] II. Conduct alkaline soil tests; Alkaline soil (pH 9-10) was selected, and the products from Examples 3 and 4, as well as Comparative Examples 1 and 2, were buried in the soil at a depth of approximately 10 cm. The soil pH and moisture content were measured regularly to maintain a relatively stable soil environment. The burial period was 3 months.

[0063] In the initial stage of the experiment, the tensile strength and elongation of the products of Examples 3 and 4 and Comparative Examples 1 and 2 were measured using a tensile testing machine. After the burial was completed, the tensile strength and elongation of the products of Examples 3 and 4 and Comparative Examples 1 and 2 were measured using a tensile testing machine. The results are shown in the table below:

[0064] As can be seen from the data in the table above, under the same burial time in alkaline soil, the products of Examples 3 and 4 showed a significantly smaller decrease in tensile strength and elongation at break compared to the products of Comparative Examples 1 and 2. This indicates that the products of Examples 3 and 4 have better corrosion resistance and stability in alkaline soil.

[0065] 3. Conduct acidic soil tests; Acidic soil (pH 4-5) was selected, and Examples 1 and 2, along with Comparative Examples 1 and 2, were buried in the soil at a depth of approximately 10 cm. The soil pH and moisture content were measured regularly to maintain a relatively stable soil environment. The experimental period was 3 months.

[0066] In the initial stage of the experiment, the tensile strength and elongation of the products of Examples 1 and 2 and Comparative Examples 1 and 2 were measured using a tensile testing machine. After the burial was completed, the tensile strength and elongation of the products of Examples 1 and 2 and Comparative Examples 1 and 2 were measured using a tensile testing machine. The results are shown in the table below:

[0067] As can be seen from the data in the table above, under the same burial time in acidic soil, the products of Examples 1 and 2 showed a significantly smaller decrease in tensile strength and elongation at break compared to the products of Comparative Examples 1 and 2. This indicates that the products of Examples 1 and 2 have better corrosion resistance and stability in acidic soil.

[0068] IV. Conduct saline-alkali soil tests; Saline-alkali soil (salt content 1-2%) was selected, and the products of Examples 5 and 6, and Comparative Examples 1 and 2 were buried in the soil at a depth of approximately 10 cm. The soil salinity, pH value, and moisture content were measured regularly to maintain a relatively stable soil environment. The experimental period was 3 months.

[0069] In the initial stage of the experiment, the tensile strength and elongation of the products of Examples 5 and 6 and Comparative Examples 1 and 2 were measured using a tensile testing machine. After the burial was completed, the tensile strength and elongation of the products of Examples 5 and 6 and Comparative Examples 1 and 2 were measured using a tensile testing machine. The results are shown in the table below:

[0070] As can be seen from the data in the table above, under the same burial time in saline-alkali soil, the products of Examples 5 and 6 showed a significantly smaller decrease in tensile strength and elongation at break compared to the products of Comparative Examples 1 and 2. This indicates that the products of Examples 5 and 6 have better corrosion resistance and stability in acidic soil.

[0071] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A graphite-based flexible grounding device, characterized in that: It includes a graphite-based flexible connecting wire (1) for connecting grounded electrical equipment and a graphite-based flexible grounding wire (2) for grounding on the ground. The graphite-based flexible connecting wire (1) and the graphite-based flexible grounding wire (2) are connected together by a connecting clamp (3). Both the graphite-based flexible connecting wire (1) and the graphite-based flexible grounding wire (2) are made of graphite-based flexible material, which is composed of the following raw materials in parts by weight: 90-95 parts expanded graphite, 10-20 parts glass fiber, 5-10 parts water-based pressure-sensitive adhesive, 5-8 parts sorbitol monooleate, 6-10 parts potassium dihydrogen phosphate, 0.5-2 parts antioxidant, 0.3-1.5 parts ultraviolet absorber, and 1-5 parts auxiliary substances. The auxiliary substances are used to improve soil adaptability and are 2-5 parts calcium carbonate, 1-3 parts boric acid, or 1-2 parts potassium dihydrogen phosphate.

2. The graphite-based flexible grounding device according to claim 1, characterized in that: The graphite-based flexible connecting wire (1) and the graphite-based flexible grounding wire (2) are in an L-shaped structure under the connection action of the connecting clamp (3). The end of the graphite-based flexible connecting wire (1) away from the connecting clamp (3) is provided with a connecting hardware (4) for connecting with electrical equipment that needs to be grounded. The segments of the graphite-based flexible connecting wire (1) and the graphite-based flexible grounding wire (2) close to the connecting clamp (3) are all in an arc shape.

3. The graphite-based flexible grounding device according to claim 1, characterized in that: Both the graphite-based flexible connecting wire (1) and the graphite-based flexible grounding wire (2) are provided with copper wires (5). The copper wires (5) are arranged in a ring array in both the graphite-based flexible connecting wire (1) and the graphite-based flexible grounding wire (2), and the center of the ring array is the center of both the graphite-based flexible connecting wire (1) and the graphite-based flexible grounding wire (2).

4. The graphite-based flexible grounding device according to claim 3, characterized in that: The diameter ratio of the copper wire (5) in the graphite-based flexible connecting wire (1) to the diameter of the graphite-based flexible connecting wire (1) is 1:5 to 10. The diameter ratio of the copper wire (5) in the graphite-based flexible grounding wire (2) to the diameter of the graphite-based flexible connecting wire (1) is also 1:5 to 10.

5. A graphite-based flexible grounding device according to claim 4, characterized in that: The ratio of the diameter of the circular structure formed by the copper wire in the graphite-based flexible connecting wire (1) to the diameter of the graphite-based flexible connecting wire (1) is 0.4 to 0.65, and the ratio of the diameter of the circular structure formed by the copper wire in the graphite-based flexible grounding wire (2) to the diameter of the graphite-based flexible grounding wire (2) is 0.4 to 0.

65.

6. A graphite-based flexible grounding device according to claim 1, characterized in that: The graphite-based flexible material is also composed of the following raw materials in parts by weight: 0.1 to 0.5 parts of conductive filler.

7. A graphite-based flexible grounding device according to claim 1, characterized in that: The expanded graphite has a particle size of 7–20 μm and is prepared by sequentially oxidizing and high-temperature expanding high-purity flake graphite. The oxidation is carried out by treating with perchloric acid and potassium permanganate, and the high-temperature expansion is carried out by treating the oxidized high-purity flake graphite at an environment of 1000–1200℃. The density of the expanded graphite is 0.002–0.003 g / cm³.

8. A graphite-based flexible grounding device according to claim 7, characterized in that: The glass fiber has a diameter of 9–15 μm and a density of 2.5–3.0 g / cm³. Sorbitol monooleate has an acid value of 6–8 mg KOH / g, a hydroxyl value of 190–250 mg KOH / g, and a saponification value of 135–160 mg KOH / g.

9. A graphite-based flexible grounding device according to claim 8, characterized in that: The method for preparing the graphite-based flexible material is as follows: expanding graphite, glass fiber, water-based pressure-sensitive adhesive, sorbitol monooleate, potassium dihydrogen phosphate, antioxidant, ultraviolet absorber and auxiliary substances are mixed, and graphite-based flexible composite material is obtained by rolling, thermoplastic and stranding processes.

10. A graphite-based flexible grounding device according to claim 9, characterized in that: The rolling temperature is 220-240℃, the rolling pressure is 130-140MPa, the rolling speed is 0.2-0.3m / s, and the thermoplastic temperature is 260-280℃.

Images