Lightweight insulating composite cross arm and preparation method thereof

Abstract

The invention provides a lightweight insulation composite cross arm. The lightweight insulation composite cross arm comprises an insulation core rod, a filler filled in the insulation core rod and an insulation umbrella skirt located outside the insulation core rod, the structure of the insulating core rod is a pipe body formed by modified continuous basalt fibers which are spirally arranged in multiple layers, and resin is adhered to the surfaces of the modified continuous basalt fibers; the structure of the modified continuous basalt fiber is as follows: basalt fiber chips are connected to the surface of the continuous basalt fiber through silica sol; the resin comprises the following raw materials: 100 parts of epoxy resin, 1-5 parts of a silane coupling agent, 5-8 parts of an auxiliary agent, 8-10 parts of basalt fiber chippings, 20-30 parts of a curing agent and 30-50 parts of a solvent. According to the invention, the continuous basalt fibers are modified by the basalt chips, and the basalt chips are used as a bridge, so that the interaction between the continuous basalt fibers and a resin matrix is increased, and the bending modulus and bending strength of the insulating core rod are improved.

Description

Technical Field

[0001] The present application relates to the technical field of power transmission supporting structures, and in particular to a lightweight insulating composite crossarm and a preparation method thereof. Background Art

[0002] The insulating composite crossarm is a new type of crossarm product with high mechanical bearing capacity and insulation properties, which is made by mixing fibers, polymer resins and additives in a certain proportion.

[0003] Insulated composite cross arms are widely used in power systems, communication systems and other fields, especially in high-voltage transmission lines, substations and other occasions.

[0004] Patent application publication CN115109386A discloses a basalt fiber reinforced epoxy resin core rod for composite insulating crossarms and a preparation method thereof. This method only uses basalt fiber impregnated with resin to wind a pipe body without any modification of the basalt fiber. The obtained basalt fiber reinforced epoxy resin core rod has poor strength.

[0005] Therefore, the requirements of mechanical properties and light weight of the insulating composite cross-arm cannot be met at the same time. Summary of the invention

[0006] The technical problem to be solved by the present invention is that the requirements of mechanical properties and light weight of the insulating composite cross arm cannot be met at the same time.

[0007] In order to solve the above problems, the present invention provides a lightweight insulating composite cross arm, comprising: an insulating core rod and a filler filled inside the insulating core rod;

[0008] The structure of the insulating core rod is: a tube body formed by multi-layer spirally arranged modified continuous basalt fibers with resin adhered to the surface;

[0009] The structure of the modified continuous basalt fiber is as follows: basalt fiber fragments are connected on the surface of the continuous basalt fiber through silica sol;

[0010] The raw materials of the resin include: 100 parts of epoxy resin, 1 to 5 parts of silane coupling agent, 5 to 8 parts of auxiliary agent, 8 to 10 parts of basalt fiber scraps, 20 to 30 parts of curing agent and 30 to 50 parts of solvent.

[0011] The present invention utilizes basalt debris to modify the continuous basalt fiber. The basalt debris serves as a bridge to increase the interaction between the continuous basalt fiber and the resin matrix, thereby improving the bending modulus and bending strength of the insulating core rod.

[0012] The present invention discloses an insulating core rod obtained by naturally dipping modified continuous basalt fibers, wherein the volume ratio of the modified continuous basalt fibers to the resin is 7-8:2-3.

[0013] Preferably, in the modified continuous basalt fiber, the mass ratio of the continuous basalt fiber to the basalt fiber scraps is 1:0.06-0.08.

[0014] Preferably, the fineness of the continuous basalt fiber is not less than 4800 tex, and the single fiber diameter of the continuous basalt fiber is not less than 16 μm.

[0015] Preferably, the thickness of the tube body of the insulating core rod is not less than 20 mm.

[0016] In order to increase the service life of the insulating core rod, preferably, the additive includes at least one of an antioxidant, a flame retardant, and an ultraviolet absorber.

[0017] Preferably, the filler is polyurethane foam material.

[0018] Preferably, the filling density of the polyurethane foam material is 0.03-0.07 g / cm 3 .

[0019] The present invention also provides a method for preparing the above-mentioned lightweight insulating composite crossarm, comprising:

[0020] Preparation of the insulating core rod: The modified continuous basalt fiber impregnated with liquid resin is wound onto a tubular mold, and heated and cured in a curing furnace. After the curing is completed, the insulating core rod is prepared;

[0021] Insulation shed molding: Place the insulating core rod inside the cavity of the shed mold, inject the silicone rubber material into the cavity of the insulator shed mold, set the hot pressing molding conditions to melt the high-temperature vulcanized silicone rubber and form it. The shed is directly wrapped on the surface of the basalt fiber winding tube during the molding process, and the insulating shed is naturally cooled after demoulding to obtain the insulation shed;

[0022] Insulating expansion material filling: filling the cavity of the insulating core rod with fillers to finally obtain a lightweight insulating composite cross arm.

[0023] Preferably, the preparation method of the modified continuous basalt fiber is: after the basalt fiber is immersed in a basalt fiber fragment-silica sol solution, heating and curing to form the modified continuous basalt fiber; preferably, the mass ratio of the basalt fiber fragment to the silica sol is 1:0.4-0.5; preferably, the silica sol is M3010 silica sol.

[0024] The beneficial effects of the present invention are:

[0025] 1. The present invention utilizes basalt debris to modify the continuous basalt fiber. The basalt debris acts as a bridge to increase the interaction between the continuous basalt fiber and the resin matrix, which helps to improve the bending modulus and bending strength of the insulating core rod.

[0026] 2. The present invention uses basalt debris to modify the continuous basalt fiber by adding silica sol, which can form a chemical bond between the surface of the continuous basalt fiber and the basalt debris, thereby significantly improving the interfacial bonding strength between the two. Silica sol can also reduce the agglomeration phenomenon on the surface of the basalt fiber debris, making the basalt fiber debris more evenly dispersed during dissolution.

[0027] 3. The present invention adds basalt fiber scraps to the resin impregnation solution. The basalt fiber scraps are used as fillers to increase the contact area between the resin and the continuous basalt fiber, thereby enhancing the interface bonding force and improving the overall performance of the insulating core rod. The addition of fiber scraps can play a role in toughening and strengthening, and improve the bending modulus and bending strength of the insulating core rod.

[0028] 4. The present invention also adds a silane coupling agent to the resin impregnation solution. The silane coupling agent molecule has an amphoteric structure. One end can react with the hydroxyl group or other active groups on the surface of the basalt fiber, and the other end can be compatible with the resin molecular chain. It can form a chemical bond between the fiber and the resin, and significantly improve the interfacial bonding strength between the two. Due to the enhanced interfacial bonding, the mechanical properties of the insulating core rod will be improved. The silane coupling agent can reduce the agglomeration of basalt fiber debris and functional additives in the resin impregnation solution, so that the basalt fiber debris and functional additives are more evenly dispersed in the resin, which helps to improve the performance of the insulating core rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the lightweight insulating composite crossarm of the present application.

[0030] Description of reference numerals:

[0031] 1. Insulating core rod; 2. Filling material; 3. Insulating shed skirt. DETAILED DESCRIPTION

[0032] The following embodiments of the technical solution of the present application will be described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0033] The present invention provides a lightweight insulating composite cross-arm and a preparation method thereof. In the present invention, the preparation method of the lightweight insulating composite cross-arm comprises:

[0034] Preparation of insulating core rod: winding the modified continuous basalt fiber soaked in liquid resin onto a tubular mold, heating and curing in a curing furnace, and preparing the insulating core rod after curing; obtaining a tube body formed by multi-layer continuous spirally arranged modified continuous basalt fibers with resin adhered to the surface.

[0035] Insulation shed molding: Place the insulating core rod inside the cavity of the shed mold, inject the silicone rubber material into the cavity of the insulator shed mold, set the hot pressing molding conditions to melt the high-temperature vulcanized silicone rubber and form it. The shed is directly wrapped on the surface of the basalt fiber winding tube during the molding process, and the insulating shed is naturally cooled after demoulding to obtain the insulation shed;

[0036] Insulation expansion material filling: Filling the cavity of the insulating core rod with filler to obtain a lightweight insulating composite cross arm.

[0037] In the preparation of the insulating core rod, the winding position of the basalt fiber is spirally wound from one end of the tube body to the other end, the winding angle is 35 to 65 degrees, and the winding angle between adjacent fiber winding layers differs by 35 to 50 degrees; the winding speed is 80 cm / s, and the winding tension is 5% of the fiber strength.

[0038] The fineness of the continuous basalt fiber is not less than 4800tex, and the single fiber diameter of the continuous basalt fiber is not less than 16μm, for example, it can be 16μm, 17μm, 18μm, 19μm, 20μm, 21μm, etc. The thickness of the liquid resin on the basalt fiber is the natural impregnation thickness, so that the volume ratio of the modified continuous basalt fiber to the resin in the insulating core rod is 7-8:2-3.

[0039] In one embodiment, the preparation method of the modified continuous basalt fiber is: after immersing the basalt fiber in a basalt fiber scrap-silica sol solution, heating and curing to form the modified continuous basalt fiber, a modified continuous basalt fiber is obtained in which the basalt fiber scraps are connected to the basalt fiber surface through the silica sol; preferably, the mass ratio of the basalt fiber scraps to the silica sol is 1:0.4-0.5; preferably, the silica sol is M3010 silica sol. In the modified continuous basalt fiber, the mass ratio of the continuous basalt fiber to the basalt fiber scraps is 1:0.06-0.08.

[0040] The raw materials of the resin include: 100 parts of epoxy resin, 1 to 5 parts of silane coupling agent, 5 to 8 parts of auxiliary agent, 8 to 10 parts of basalt fiber scraps, 20 to 30 parts of curing agent and 30 to 60 parts of solvent. The auxiliary agent includes: at least one of an antioxidant, a flame retardant and an ultraviolet absorber.

[0041] By the above method, a lightweight insulating composite cross arm can be obtained, which includes an insulating core rod and a filler filled inside the insulating core rod, wherein the filler is a polyurethane foam material. The filling density of the polyurethane foam material is 0.03-0.07 g / cm 3 .

[0042] The technical scheme and effect of the present invention are described below by specific examples. In the following examples, the length of the basalt fiber scraps used is basalt short fibers not exceeding 1 mm, the silane coupling agent used is vinyl triethoxysilane, and the solvent used is DMAC.

[0043] Embodiment 1:

[0044] Preparation of modified continuous basalt fiber: BMⅡ type continuous basalt fiber with a fineness of 9600tex and a single diameter of 19μm was naturally impregnated with basalt fiber debris-M3010 silica sol, and then heated and cured to form modified continuous basalt fiber; the mass ratio of basalt fiber debris to silica sol was 1:0.4, and the mass ratio of continuous basalt fiber to basalt fiber debris in the obtained modified continuous basalt fiber (m 连续纤维 :m 纤维碎屑 ) is approximately 1:0.08.

[0045] Liquid resin preparation: 100 parts of bisphenol A epoxy resin, 1 part of silane coupling agent, 1 part of antioxidant, 2 parts of flame retardant, 2 parts of ultraviolet absorber auxiliary, 8 parts of basalt fiber scraps, 20 parts of curing agent and 30 parts of solvent are fully mixed to obtain liquid resin.

[0046] Preparation of insulating core rod: The modified continuous basalt fiber soaked in liquid resin is wound onto a tubular mold and heated and cured in a curing furnace. After the curing is completed, an insulating core rod is prepared. In the obtained insulating core rod, the volume ratio of the modified continuous basalt fiber to the resin (V 连续玄武岩纤维 :V 树脂 ) is about 7:3, and is wound to form a tube body with a thickness of 20 mm and an outer diameter of 76 mm;

[0047] Insulation shed molding: Inject silicone rubber into the cavity of the insulator shed mold, set the molding pressure to 6MPa, the molding temperature to 200℃, and the holding time to 30min, so that the high-temperature vulcanized silicone rubber is melted and molded. The shed is directly wrapped on the surface of the insulating core rod during the molding process, and the insulating shed is naturally cooled after demoulding to obtain the insulating shed;

[0048] Insulation expansion material filling: The cavity of the insulating core rod is filled with polyurethane foam material with a filling density of 0.05g / cm 3 , and obtain a lightweight insulating composite crossarm.

[0049] Embodiment 2 to Embodiment 5

[0050] The difference between Example 2 to Example 5 and Example 1 is that the control parameters of each step are different, see Table 1 for details.

[0051] Comparative Example 1

[0052] The difference between Comparative Example 1 and Example 3 is that the continuous basalt fiber used in Comparative Example 1 is not modified in any way. The control parameters of each step of Comparative Example 1 are shown in Table 1.

[0053] Comparative Example 2

[0054] The difference between Comparative Example 2 and Example 3 is that in Comparative Example 2, ethanol is used instead of silica sol when modifying the continuous basalt fiber. The control parameters of each step of Comparative Example 2 are shown in Table 1.

[0055] The difference between Comparative Example 3 and Example 3 is that no basalt fiber crumbs are added to the liquid resin used in Comparative Example 3. The control parameters of each step of Comparative Example 3 are shown in Table 1.

[0056] The difference between Comparative Example 4 and Example 3 is that no silane coupling agent is added to the liquid resin used in Comparative Example 4. The control parameters of each step of Comparative Example 4 are shown in Table 1.

[0057] Table 1 Control conditions of each step in each embodiment and comparative example

[0058]

[0059]

[0060] The lightweight insulating composite cross-arms prepared in the above-mentioned embodiments and comparative examples were tested for bending modulus, bending strength and electrical breakdown strength. The test results are shown in Table 2.

[0061] Table 2 Performance test results of lightweight insulating composite crossarms obtained in various embodiments and comparative examples

[0062]

[0063]

[0064] It can be seen from Table 2 that the lightweight insulating composite cross-arms obtained in Examples 1 to 5 have good bending modulus and bending strength, and have better electrical breakdown strength.

[0065] According to the method for preparing the composite cross-arm of the present invention and Examples 1 to 5, the following voltage level and tower type requirements can be met by adjusting the cross-arm size according to relevant standard regulations:

[0066] 35kV: gate tower, upper letter type;

[0067] 110kV: gate tower, upper letter type;

[0068] 220kV: gate-type tower, up-shaped tower, V-shaped tower;

[0069] 330kV: portal tower, V-type tower;

[0070] 500kV: portal tower.

[0071] It can be seen from Table 2 that compared with Example 3, the bending modulus and bending strength of the lightweight insulating composite crossarm obtained in Comparative Example 1 are weaker. This is because the continuous basalt fiber is not modified in Comparative Example 1, resulting in a decrease in product performance compared with Examples 1 to 5. This shows that in Examples 1 to 5, the basalt debris acts as a bridge to increase the interaction between the continuous basalt fiber and the resin matrix, which helps to improve the bending modulus and bending strength of the insulating core rod.

[0072] Compared with Example 3, the bending modulus and bending strength of the lightweight insulating composite crossarm obtained in Comparative Example 2 are better than those in Comparative Example 1, but relatively poor. This is because when the continuous basalt fiber is modified by basalt debris in Comparative Example 2, silica sol is not added, resulting in less adhesion of basalt debris on the basalt fiber and weak adhesion. Silica sol is added in Examples 1 to 5, and silica sol can form a chemical bond between the surface of the continuous basalt fiber and the basalt debris, thereby significantly improving the interface bonding strength between the two.

[0073] Compared with Example 3, the bending modulus and bending strength of the lightweight insulating composite crossarm obtained in Comparative Example 3 are weaker. This is because the liquid resin of Comparative Example 3 does not contain basalt fiber crumbs, while in Examples 1 to 5, basalt fiber crumbs are used as fillers to increase the contact area between the resin and the continuous basalt fibers, thereby enhancing the interfacial bonding force and improving the overall performance of the insulating core rod.

[0074] Compared with Example 3, the bending modulus and bending strength of the lightweight insulating composite crossarm obtained in Comparative Example 4 are weaker. This is because no silane coupling agent is added to the liquid resin of Comparative Example 4, while in Examples 1 to 5, a silane coupling agent is also added to the resin impregnation solution. The silane coupling agent molecule has an amphoteric structure, one end of which can be connected to the active group on the surface of the basalt fiber, and the other end is compatible with the resin molecular chain, which can form a chemical bond between the fiber and the resin, significantly improving the interfacial bonding strength between the two.

[0075] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A lightweight insulating composite cross arm, characterized in that: include: An insulating core rod (1), a filler (2) filled inside the insulating core rod, and an insulating shed (3) located outside the insulating core rod; The structure of the insulating core rod (1) is: a tube body formed by multiple layers of spirally arranged modified continuous basalt fibers with resin adhered to the surface; The structure of the modified continuous basalt fiber is as follows: basalt fiber fragments are connected to the surface of the continuous basalt fiber through silica sol; The raw materials of the resin include: 100 parts of epoxy resin, 1 to 5 parts of silane coupling agent, 5 to 8 parts of auxiliary agent, 8 to 10 parts of basalt fiber scraps, 20 to 30 parts of curing agent and 30 to 60 parts of solvent.

2. The lightweight insulating composite crossarm according to claim 1, characterized in that: In the insulating core rod, the volume ratio of the modified continuous basalt fiber to the resin is 7-8:2-3.

3. The lightweight insulating composite crossarm according to claim 1 is characterized in that: In the modified continuous basalt fiber, the mass ratio of the continuous basalt fiber to the basalt fiber fragments is 1:0.06-0.

08.

4. The lightweight insulating composite crossarm according to claim 1, characterized in that: The fineness of the continuous basalt fiber is not less than 4800tex, and the single fiber diameter of the continuous basalt fiber is not less than 16μm.

5. The lightweight insulating composite crossarm according to claim 1, characterized in that: The thickness of the tube body of the insulating core rod is not less than 20 mm.

6. The lightweight insulating composite crossarm according to claim 1, characterized in that: The auxiliary agent includes at least one of an antioxidant, a flame retardant, and an ultraviolet absorber.

7. The lightweight insulating composite crossarm according to claim 1, characterized in that: The filler is a polyurethane foam material.

8. The lightweight insulating composite crossarm according to claim 7, characterized in that: The filling density of the polyurethane foam material is 0.03-0.07 g / cm 3 .

9. A method for preparing the lightweight insulating composite cross-arm according to any one of claims 1 to 8, characterized in that: include: Preparation of the insulating core rod: The modified continuous basalt fiber impregnated with liquid resin is wound onto a tubular mold, and heated and cured in a curing furnace. After the curing is completed, the insulating core rod is prepared; Insulation shed molding: Place the insulating core rod inside the cavity of the shed mold, inject the silicone rubber material into the cavity of the insulator shed mold, set the hot pressing molding conditions to melt the high-temperature vulcanized silicone rubber and form it. The shed is directly wrapped on the surface of the basalt fiber winding tube during the molding process, and the insulating shed is naturally cooled after demoulding to obtain the insulating shed. Insulating expansion material filling: filling the cavity of the insulating core rod with fillers to finally obtain a lightweight insulating composite cross arm.

10. The method according to claim 9, characterized in that The preparation method of the modified continuous basalt fiber is: immersing the basalt fiber in a basalt fiber scrap-silica sol solution, and then heating and curing the solution to form the modified continuous basalt fiber; preferably, the mass ratio of the basalt fiber scrap:silica sol is 1:0.4-0.5; preferably, the silica sol is M3010 silica sol.

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