Chopped fiber reinforced resin-based composite electric power fitting and preparation method thereof

Abstract

The invention provides a chopped fiber reinforced resin-based composite electric power fitting and a preparation method thereof, and relates to the technical field of electric power system composite electric power fitting processing.The preparation method comprises the steps that firstly, resin, a curing agent, an accelerant and chopped fibers are weighed according to the proportion and mixed to be uniform, and then a resin mixture is prepared; carrying out pre-curing treatment on the resin mixture in a vacuum drying oven; stirring the resin mixture by using a planetary stirrer and vacuumizing; pouring the pre-cured resin mixture into a pre-designed casting mold through a vacuum pipeline; and finally, putting the casting mold into a vacuum drying oven, and curing at a preset temperature to obtain the composite electric power fitting. The composite electric power fitting is prepared by combining the chopped fibers with the resin mixture, and the production process is low in energy consumption and free of environmental pollution; the composite electric power fitting has excellent insulation performance, and the insulation level of the whole system is improved; on the premise of meeting the mechanical design requirement, the weight of the composite electric power fitting is greatly reduced, and the characteristics and advantages of light weight and high strength of the composite material are embodied.

Description

Technical Field

[0001] The invention relates to the technical field of composite electric hardware processing of electric power systems, and in particular to a chopped fiber reinforced resin-based composite electric hardware and a preparation method thereof. Background Art

[0002] Power fittings refer to various metal accessories used in power systems, including conductors, insulators, grounding devices, support frames, etc. In power systems, power fittings play a very important role. They are used to connect, fix and support power equipment and power cables to ensure the normal operation, safety and stability of the power system. Among them, conductor fittings are mainly used to connect and fix the conductors of transmission lines; insulator fittings are used to connect and fix insulators to play a supporting and isolating role; grounding devices are used to protect power equipment and personnel from the harm of leakage; support frames are used to support power equipment and cables to ensure their stable and reliable operation.

[0003] Since power fittings bear great pressure and load, improving them is of great significance to the safe and stable operation of the power system. At present, the fittings used in the industry are usually metal accessories made of iron, aluminum or aluminum alloy. Such fittings have the disadvantages of high cost, high energy consumption in the production process, high weight, reliance on galvanized layer for corrosion protection, poor insulation performance, and unsuitability for special environments. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a chopped fiber reinforced resin-based composite power hardware and a preparation method thereof. The composite power hardware is light in weight, does not require additional plating, has low energy consumption in the production process, has no environmental pollution, has good insulation effect, can improve the overall insulation level of the power system, and is conducive to the safe and stable operation of the power system.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A chopped fiber reinforced resin-based composite electric hardware, which uses chopped fibers and a resin mixture as basic materials and is prepared through a vacuum casting process.

[0007] Preferably, the composite power fittings include composite cross-arm end fittings, wire hanging fittings and insulator end fittings.

[0008] Preferably, the chopped fibers are inorganic fibers.

[0009] Preferably, the chopped fibers include glass fibers and basalt fibers.

[0010] Preferably, the mass fraction of the chopped fibers accounts for 1%-30% of the composite electrical hardware.

[0011] Preferably, the resin mixture is composed of 100 parts of resin, 75-85 parts of curing agent, and 0.5-1.5 parts of accelerator. The resin is a high-performance wear-resistant resin such as polysulfone, polyphenylene sulfide, bisphenol A resin, polyimide, polytetrafluoroethylene, etc., the curing agent is methyl hexahydrophthalic anhydride, and the accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

[0012] Preferably, the interface of the composite electrical fitting is any one of a circle, an ellipse, a regular polygon or an irregular polygon.

[0013] Preferably, when the interface is circular or elliptical, the diameter range of the interface is

[0014] Preferably, the composite electrical fitting is installed on the mandrel by a crimping connection process.

[0015] A method for preparing the above-mentioned chopped fiber reinforced resin-based composite electric hardware comprises:

[0016] Weigh the resin, curing agent, accelerator and chopped fibers in proportion, mix them evenly to form a resin mixture;

[0017] Pre-curing the resin mixture in a vacuum drying oven; the pre-curing temperature is 50-80°C, and the pre-curing time is 30 minutes to 1 hour;

[0018] Use a planetary mixer to stir the resin mixture evenly while applying vacuum to avoid the generation of bubbles;

[0019] The pre-cured resin mixture is poured into a pre-designed mold through a vacuum pipe. The resin mixture will not come into contact with oxygen during flow, thus avoiding oxidation reaction and mixing of impurities, ensuring the purity and quality of the casting;

[0020] The mold is placed in a vacuum drying oven and cured at a preset temperature to obtain a composite electrical fitting. The preset curing temperature is 120-400°C and the curing time is 30 minutes to 24 hours.

[0021] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0022] (1) The chopped fibers combined with the resin mixture used in the present invention are used to prepare the composite electrical fittings. Compared with the traditional electrical fittings, the production process has low energy consumption and no environmental pollution.

[0023] (2) The composite electrical fittings prepared by the present invention have better insulation performance, which is beneficial to improving the overall insulation level of the system.

[0024] (3) The composite electrical hardware prepared by the present invention meets the requirements of mechanical design and has a greatly reduced weight, reflecting the characteristics and advantages of composite materials that are lightweight and high-strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0026] Figure 1 A schematic diagram of a preparation process provided by an embodiment of the present invention;

[0027] Figure 2 A schematic diagram of a composite fixing hardware provided by an embodiment of the present invention;

[0028] Figure 3 A schematic diagram of an insulator end fitting provided in an embodiment of the present invention;

[0029] Figure 4 A schematic diagram of a composite wire hanging fitting provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] like Figure 1 As shown, the present invention provides a method for preparing a chopped fiber reinforced resin-based composite electric hardware, comprising:

[0032] Step 100: Weigh the resin, curing agent, accelerator, and chopped fibers in proportion, and mix them evenly to form a resin mixture;

[0033] Step 200: pre-curing the resin mixture in a vacuum drying oven;

[0034] Step 300: Use a planetary stirrer to stir the resin mixture evenly, and simultaneously evacuate to avoid the generation of bubbles;

[0035] Step 400: pouring the pre-cured resin mixture into a pre-designed casting mold through a vacuum pipe;

[0036] Step 500: placing the mold into a vacuum drying oven and curing it at a preset temperature to obtain a composite electrical fitting.

[0037] like Figures 2 to 4 As shown, the composite power fittings prepared by the present invention include composite cross arm end fittings, wire hanging fittings and insulator end fittings.

[0038] The present invention is further described below through specific implementation methods. The fibers used in the embodiments of the present invention are all chopped basalt fibers, the resin is bisphenol A epoxy resin, and the hardware made is a wire hanging hardware.

[0039] Example 1

[0040] A chopped fiber reinforced resin-based composite power fitting is prepared by a vacuum casting process using a mixture of chopped fibers and resin as basic materials. The specific preparation steps are as follows:

[0041] (1) weighing 100 parts by weight of bisphenol A diglycidyl ether, 80 parts by weight of methyl hexahydrophthalic anhydride curing agent, and 0.8 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol in proportion, and then mixing them uniformly at room temperature to prepare a resin mixture;

[0042] (2) taking 5% by mass of chopped basalt fibers and adding them to the resin mixture;

[0043] (3) pre-curing the resin mixture in a vacuum drying oven at a pre-curing temperature of 80° C. for 40 minutes;

[0044] (4) using a planetary stirrer to stir the resin mixture evenly while evacuating the mixture to avoid the generation of bubbles;

[0045] (4) pouring the pre-cured resin mixture into a pre-designed casting mold through a vacuum pipe;

[0046] (5) The mold was placed in a vacuum drying oven and cured at 120°C for 12 hours.

[0047] Example 2

[0048] A chopped fiber reinforced resin-based composite power fitting is prepared by a vacuum casting process using a mixture of chopped fibers and resin as basic materials. The specific preparation steps are as follows:

[0049] (1) weighing 100 parts by weight of bisphenol A diglycidyl ether, 80 parts by weight of methyl hexahydrophthalic anhydride curing agent, and 0.8 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol in proportion, and then mixing them uniformly at room temperature to prepare a resin mixture;

[0050] (2) taking 10% by mass of chopped basalt fibers and adding them to the resin mixture;

[0051] (3) pre-curing the resin mixture in a vacuum drying oven at a pre-curing temperature of 80° C. for 40 minutes;

[0052] (4) using a planetary stirrer to stir the resin mixture evenly while evacuating the mixture to avoid the generation of bubbles;

[0053] (4) pouring the pre-cured resin mixture into a pre-designed casting mold through a vacuum pipe;

[0054] (5) The mold was placed in a vacuum drying oven and cured at 120°C for 12 hours.

[0055] Example 3

[0056] A chopped fiber reinforced resin-based composite power fitting is prepared by a vacuum casting process using a mixture of chopped fibers and resin as basic materials. The specific preparation steps are as follows:

[0057] (1) weighing 100 parts by weight of bisphenol A diglycidyl ether, 80 parts by weight of methyl hexahydrophthalic anhydride curing agent, and 0.8 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol in proportion, and then mixing them uniformly at room temperature to prepare a resin mixture;

[0058] (2) taking 20% ​​by mass of chopped basalt fibers and adding them to the resin mixture;

[0059] (3) pre-curing the resin mixture in a vacuum drying oven at a pre-curing temperature of 80° C. for 40 minutes;

[0060] (4) using a planetary stirrer to stir the resin mixture evenly while evacuating the mixture to avoid the generation of bubbles;

[0061] (4) pouring the pre-cured resin mixture into a pre-designed casting mold through a vacuum pipe;

[0062] (5) The mold was placed in a vacuum drying oven and cured at 120°C for 12 hours.

[0063] Comparative Example 1

[0064] A chopped fiber reinforced resin-based composite power fitting is prepared by a vacuum casting process using a mixture of chopped fibers and resin as basic materials. The specific preparation steps are as follows:

[0065] (1) weighing 100 parts by weight of bisphenol A diglycidyl ether, 80 parts by weight of methyl hexahydrophthalic anhydride curing agent, and 0.8 parts by weight of 2,4,6-tris(dimethylaminomethyl)phenol in proportion, and then mixing them uniformly at room temperature to prepare a resin mixture;

[0066] (2) taking 10% by mass of chopped glass fibers and adding them to the resin mixture;

[0067] (3) pre-curing the resin mixture in a vacuum drying oven at a pre-curing temperature of 80° C. for 40 minutes;

[0068] (4) using a planetary stirrer to stir the resin mixture evenly while evacuating the mixture to avoid the generation of bubbles;

[0069] (4) pouring the pre-cured resin mixture into a pre-designed casting mold through a vacuum pipe;

[0070] (5) The mold was placed in a vacuum drying oven and cured at 120°C for 12 hours.

[0071] Comparative Example 2

[0072] A chopped fiber reinforced resin-based composite power fitting is prepared by a vacuum casting process using chopped fibers and polyurethane as basic materials. The specific preparation steps are as follows:

[0073] (1) Take 10% by mass of chopped basalt fibers and add them into polyurethane resin;

[0074] (2) pre-curing the resin mixture in a vacuum drying oven at a pre-curing temperature of 40° C. for 40 minutes;

[0075] (3) using a planetary stirrer to stir the resin mixture evenly while evacuating the mixture to avoid the generation of bubbles;

[0076] (4) pouring the pre-cured resin mixture into a pre-designed casting mold through a vacuum pipe;

[0077] (5) The mold was placed in a vacuum drying oven and cured at 60°C for 12 hours.

[0078] According to the above steps, composite power fittings were prepared to obtain 1# composite power fittings (Comparative Example 1), 2# composite power fittings (Comparative Example 2), 3# composite power fittings (Example 1), 4# composite power fittings (Example 2), and 5# composite power fittings (Example 3), respectively. The performance of the composite power fittings was tested. The testing method is as follows. The specific test results are shown in Table 1:

[0079] 1) Power frequency breakdown test: Refer to GB / T16927.1-2011, use parallel plate electrodes to increase the voltage at a uniform rate of 2kV / s until the sample breaks down. Place a 1mm thick test piece in a transparent glass container filled with dimethyl silicone oil, ensuring that the silicone oil covers the sample by 5-7mm. Take at least 10 breakdown test points for statistics.

[0080] 2) Dielectric loss test: Referring to GB / T1409-2006, an Agilent-4294A impedance analyzer was used to apply 9kV voltage to the sample. At least three samples were tested.

[0081] 3) Leakage current test: The composite material is sampled using a digital leakage current measuring device DM3068. The sampling frequency is 20 Hz, the test voltage is 12 kV, and the voltage rise rate is 1 kV / s. At least three samples are tested.

[0082] 4) Wear test: Wear test was conducted in accordance with GB / T3960-2016. The contact surface and load of the sample were kept constant during the test, and the friction time was 3 minutes. At least three samples were tested.

[0083] Table 1 Test results

[0084] Group Breakdown field strength / kV / mm Dielectric loss angle Leakage current / μA Friction loss / g 1# Composite power fittings 31.23 0.28％ 51.322 0.3628 2# Composite power fittings 18.26 0.36％ 65.811 0.5962 3# Composite power fittings 40.74 0.29％ 53.433 0.3265 4# Composite power fittings 32.06 0.32％ 43.457 0.2415 5# Composite power fittings 30.8 0.34％ 45.066 0.3297

[0085] It can be seen that the chopped fiber reinforced resin-based composite power fittings of the present invention have good electrical properties, especially when chopped basalt fibers with a mass fraction of 10% are used as the reinforcing material and epoxy resin is used as the matrix material. The leakage current is the lowest and the wear performance is the best. At the same time, the breakdown field strength and the dielectric loss angle are also maintained at a high level. Taking all factors into consideration, the best choice of the present invention is a chopped basalt fiber reinforced epoxy resin-based composite material with a mass fraction of 10%. The composite power fittings of the present invention can pass the power frequency breakdown test, dielectric loss test, leakage current test and wear test required by the standard, and meet the basic requirements for grid operation.

[0086] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0087] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A chopped fiber reinforced resin-based composite electrical hardware, characterized in that: The composite electric power fitting is prepared by using chopped fibers and a resin mixture as basic materials through a vacuum casting process.

2. The chopped fiber reinforced resin-based composite electrical hardware according to claim 1, characterized in that: The composite power fittings include composite cross arm end fittings, wire hanging fittings and insulator end fittings.

3. The chopped fiber reinforced resin-based composite electrical hardware according to claim 1, characterized in that: The chopped fibers include one or more mixed inorganic fibers selected from glass fibers and basalt fibers.

4. The chopped fiber reinforced resin-based composite electrical hardware according to claim 1, characterized in that: The mass fraction of the chopped fibers accounts for 1%-30% of the composite electrical hardware.

5. The chopped fiber reinforced resin-based composite electrical hardware according to claim 1, characterized in that: The resin mixture is prepared from 100 parts of resin, 75-85 parts of curing agent and 0.5-1.5 parts of accelerator.

6. The chopped fiber reinforced resin-based composite electrical hardware according to claim 1, characterized in that: The interface of the composite electric power fitting is any one of a circle, an ellipse, a regular polygon or an irregular polygon.

7. The chopped fiber reinforced resin-based composite electrical hardware according to claim 6, characterized in that: When the interface of the composite power fitting is circular or elliptical, the diameter range of the interface of the composite power fitting is 8. The chopped fiber reinforced resin-based composite electrical hardware according to claim 1, characterized in that: The composite electric power fitting is installed on the core rod through a crimping connection process.

9. A method for preparing the chopped fiber reinforced resin-based composite electrical hardware according to any one of claims 1 to 8, characterized in that: include: Weigh the resin, curing agent, accelerator and chopped fibers in proportion, mix them evenly to form a resin mixture; Pre-curing the resin mixture in a vacuum drying oven; Use a planetary mixer to stir the resin mixture evenly while applying vacuum to avoid the generation of bubbles; The pre-cured resin mixture is poured into a pre-designed casting mold through a vacuum pipe; The casting mold is placed in a vacuum drying oven and cured at a preset temperature to obtain a composite electrical fitting.

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