Moisture-proof impregnated paper composite insulating sleeve as well as preparation method and application thereof

Abstract

The invention relates to the technical field of electrical equipment, in particular to a moisture-proof impregnated paper composite insulating sleeve and a preparation method and application thereof. The moisture-proof impregnated paper composite insulating sleeve provided by the invention comprises an impregnated paper capacitor core body and a moisture-proof enhancement layer on the outer surface, the moisture-proof reinforcing material comprises at least one of glass fiber, polyester and polyolefin, and the polyester comprises polyethylene glycol terephthalate; the impregnated paper capacitor core body comprises a central conductive tube, impregnated paper and a capacitor plate; the impregnated paper and the capacitor plates are alternately coated on the outer surface of the central conductive tube from inside to outside, and the impregnated paper or the capacitor plates are arranged on the outermost layer of the impregnated paper capacitor core body. According to the invention, the moisture-proof reinforcing layer is arranged on the outer surface of the impregnated paper capacitor core body, so that moisture in air during storage and trace moisture in transformer oil during operation can be effectively prevented from invading the impregnated paper capacitor core body, the capacitor core body is prevented from being affected with damp, the electrical property is reduced, the mechanical bending strength is enhanced, and the service life of the capacitor sleeve is prolonged.

Description

Technical Field

[0001] This invention relates to the field of electrical equipment technology, specifically to a moisture-proof adhesive-impregnated paper composite insulating sleeve, its preparation method, and its application. Background Technology

[0002] Impregnated paper sleeves are capacitor cores made by using a metal tube as the central conduit, winding corrugated insulating paper and setting an aluminum foil shielding layer, and vacuum impregnating with epoxy resin and curing process. The outermost layer is impregnated cellulose paper. Impregnated paper sleeves are mainly used in power equipment and electrical installations to isolate live parts from grounding parts, fix leads and ensure safe operation of circuits. However, existing impregnated paper sleeves have the following problems: (1) Cellulose materials are highly hygroscopic, and the dielectric loss tangent increases by 30-50% when the humidity is >60%; (2) The typical value of axial bending strength is <200MPa, which is insufficient, making the impregnated paper sleeves more sensitive to mechanical impact and vibration, especially near the flange where stress is relatively concentrated and micro-cracks are easily generated during transportation and installation; (3) The existing moisture-proof paint layer thickness is <0.5mm, which has limited mechanical reinforcement effect and is prone to cracking. The existence of the above problems means that the existing impregnated paper sleeves will suffer from deterioration of insulation performance and shortened lifespan due to moisture absorption during long-term use. It may also cause a chain of problems such as partial discharge and decline in mechanical performance, which may lead to equipment failure in severe cases. Therefore, improving the moisture-proof performance and mechanical strength of impregnated paper sleeves is of great significance. Summary of the Invention

[0003] Therefore, the purpose of this invention is to provide a moisture-proof adhesive-impregnated paper composite insulating sleeve, its preparation method, and its application. The moisture-proof adhesive-impregnated paper composite insulating sleeve provided by this invention has excellent moisture-proof performance and mechanical strength.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a moisture-proof adhesive-impregnated paper composite insulating sleeve, comprising an adhesive-impregnated paper capacitor core and a moisture-proof reinforcing layer covering the outer surface of the adhesive-impregnated paper capacitor core; The moisture-proof reinforcing material in the moisture-proof reinforcing layer includes at least one of glass fiber, polyester and polyolefin, wherein the polyester includes polyethylene terephthalate. The impregnated paper capacitor core includes a central conductive tube, impregnated paper, and capacitor plates; the impregnated paper and capacitor plates alternately cover the outer surface of the central conductive tube from the inside out, and the outermost layer of the impregnated paper capacitor core is either impregnated paper or capacitor plates.

[0005] Preferably, the polyolefin includes at least one of polypropylene and polyethylene.

[0006] Preferably, the winding angle of the moisture-proof reinforcing material in the moisture-proof reinforcing layer is 40~90°.

[0007] Preferably, the thickness of the moisture-proof reinforcement layer is ≥5mm.

[0008] Preferably, when the outermost layer of the impregnated paper capacitor core is impregnated paper, a coupling agent coating is further provided between the impregnated paper capacitor core and the moisture-proof reinforcement layer.

[0009] Preferably, the coupling agent in the coupling agent coating includes at least one of silane coupling agents, titanate coupling agents, aluminate coupling agents, phosphate coupling agents, borate coupling agents, and organochromium complexes.

[0010] This invention also provides a method for preparing the moisture-proof adhesive-impregnated paper composite insulating sleeve described in the above technical solution. When the outermost layer of the impregnated paper capacitor core is impregnated paper, the preparation method includes method 1, method 2 or method 3; Method 1 includes the following steps: S11. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube, impregnate with adhesive and then cure to obtain the adhesive-impregnated paper capacitor core. S12. The moisture-proof reinforcing material is wet-coated onto the outer surface of the impregnated paper capacitor core and cured to obtain the moisture-proof impregnated paper composite insulating sleeve. Method 2 includes the following steps: S21. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube, impregnate with adhesive and then cure to obtain the adhesive-impregnated paper capacitor core. The moisture-proof reinforcing material is processed into moisture-proof reinforcing material pipes; S22. Apply adhesive to the outer surface of the paper-impregnated capacitor core and / or the inner surface of the moisture-proof reinforcing material tube, then assemble the paper-impregnated capacitor core and the moisture-proof reinforcing material tube, and cure to obtain the moisture-proof paper-impregnated composite insulating sleeve. Method 3 includes the following steps: S31. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube to obtain an uncured, resin-impregnated capacitor core. The moisture-proof reinforcing material is processed into a moisture-proof reinforcing material tube with one end closed; S32. Assemble the uncured glue-impregnated capacitor core with the moisture-proof reinforcing material tube, and cure it after glue impregnation to obtain the moisture-proof glue-impregnated paper composite insulating sleeve. When the outermost layer of the impregnated paper capacitor core is a capacitor plate, the preparation method includes method 4, which includes the following steps: All the insulating paper and capacitor plates are alternately wound around the outer surface of the central conductive tube. Moisture-proof reinforcing material is coated on the outer surface of the outermost capacitor plate. After impregnation with resin, the material is cured to obtain the moisture-proof resin-impregnated paper composite insulating sleeve.

[0011] Preferably, in both method 1 and method 2, after alternating winding, the process further includes drying the core obtained by alternating winding; In step S12, before the wet coating, the process further includes: preheating the glue-impregnated paper capacitor core, coating the outer surface with a coupling agent, and then drying it; the wet coating includes wet winding, glue bonding, or vacuum impregnation. In step S22, before coating the outer surface of the paper-impregnated capacitor core with adhesive, the process further includes: preheating the paper-impregnated capacitor core, coating the outer surface with coupling agent and then drying it, and / or preheating the moisture-proof reinforcing material tube before coating the inner surface of the moisture-proof reinforcing material tube with adhesive, coating the inner wall with coupling agent and then drying it. In step S32, the process before assembly further includes: preheating the moisture-proof reinforcing material tube, coating the inner wall with a coupling agent, and then drying it; the process after assembly further includes: drying the assembled material. Method 4 further includes drying the core after it has been coated with moisture-proof reinforcing material before impregnation.

[0012] Preferably, step S22 is replaced by: S22' Assemble the impregnated paper capacitor core with the moisture-proof reinforcing material tube, fill the assembly gap with adhesive, then assemble the impregnated paper capacitor core with the moisture-proof reinforcing material tube, and cure to obtain the moisture-proof impregnated paper composite insulating sleeve. The assembly process described in step S22' further includes: preheating the moisture-proof reinforcing material tube, coating the inner wall with a coupling agent and then drying it, and / or preheating the impregnated paper capacitor core, coating the outer surface with a coupling agent and then drying it.

[0013] This invention also provides the application of the moisture-proof impregnated paper composite insulating sleeve described in the above-described technical solution or the moisture-proof impregnated paper composite insulating sleeve prepared by the above-described technical solution in electrical equipment. This invention incorporates a moisture-proof reinforcing layer on the outer surface of the impregnated paper capacitor core. This significantly reduces the moisture absorption capacity of the cellulose paper material, effectively preventing the impregnated paper capacitor core from becoming damp. During long-term use, it prevents insulation performance degradation due to moisture absorption, resulting in a long service life, undiminished mechanical properties, and reduced equipment failure. By controlling the type of moisture-proof reinforcing material, this invention significantly enhances the bending strength of the impregnated paper capacitor core, giving the moisture-proof impregnated paper composite insulating bushing excellent moisture-proof, shock-resistant insulation performance, and mechanical strength. It is insensitive to mechanical impact and vibration, and even during transportation and installation where stress is relatively concentrated near the flange, it is less prone to micro-cracks. This significantly extends the service life of the impregnated paper capacitor core and also reduces the storage and packaging requirements for this type of transformer bushing. The paper-impregnated capacitor core provided by this invention has excellent moisture-proof performance and mechanical strength. It forms a triple protection structure on the surface of the paper-impregnated capacitor core, which provides moisture protection, increased bending strength and impact resistance. It has good application prospects in electrical equipment, and is especially suitable for 0~1100kV AC paper-impregnated dry-type transformer bushings, paper-impregnated dry-type AC through-wall bushings, paper-impregnated AC GIS bushings, ±10~±1100kV paper-impregnated DC through-wall bushings and paper-impregnated DC valve-side transformer bushings.

[0014] The method for preparing the moisture-proof impregnated paper composite insulating sleeve provided by this invention is simple in process, easy to operate, and has low production cost, making it suitable for industrial production. Among them, the preparation process of method 4 is even simpler and more operable; method 3 is highly operable and can also save on casting molds in the production process, saving mold costs and providing good control over material costs. Attached Figure Description

[0015] Figure 1 A schematic diagram of the cross-sectional structure of a moisture-proof adhesive-impregnated paper composite insulating sleeve; Figure 2 A schematic diagram of the longitudinal section structure of a moisture-proof adhesive-impregnated paper composite insulating sleeve; Figure 3 This is a schematic diagram of the longitudinal section structure of the resin-impregnated paper capacitor core prepared in Example 1; Figure 4 Deformation cloud diagrams comparing the differences in maximum horizontal displacement when a horizontal force of 2000N is applied to the upper part of the resin-impregnated paper capacitor core prepared in Example 1; Figure 5 Deformation cloud diagrams comparing the differences in maximum horizontal displacement when a horizontal force of 2000N is applied to the upper part of the moisture-proof adhesive-impregnated paper composite insulating sleeve prepared in Example 4; Figure 6 The image shows the deformation contours of the impregnated paper capacitor core prepared in Example 1 under different radial forces when the maximum displacement is 10 mm. Figure 7The image shows the deformation contours of the moisture-proof adhesive-impregnated paper composite insulating sleeve prepared in Example 4 under different radial forces when the maximum displacement is 10 mm. Detailed Implementation

[0016] This invention provides a moisture-proof adhesive-impregnated paper composite insulating sleeve (see structural schematic diagram). Figures 1-2 It includes a paper-impregnated capacitor core and a moisture-proof reinforcing layer covering the outer surface of the paper-impregnated capacitor core; The moisture-proof reinforcing material in the moisture-proof reinforcing layer includes at least one of glass fiber, polyester and polyolefin, wherein the polyester includes polyethylene terephthalate. The impregnated paper capacitor core includes a central conductive tube, impregnated paper, and capacitor plates; the impregnated paper and capacitor plates alternately cover the outer surface of the central conductive tube from the inside out, and the outermost layer of the impregnated paper capacitor core is either impregnated paper or capacitor plates.

[0017] The moisture-proof adhesive-impregnated paper composite insulating sleeve provided by this invention includes an adhesive-impregnated paper capacitor core, which comprises a central conductive tube, adhesive-impregnated paper, and capacitor plates. The adhesive-impregnated paper and capacitor plates alternately cover the outer surface of the central conductive tube from the inside out, and the outermost layer of the adhesive-impregnated paper capacitor core is either adhesive-impregnated paper or capacitor plates. The adhesive-impregnated paper is in contact with the central conductive tube. In this invention, the material of the central conductive tube includes aluminum and / or copper; the central conductive tube is a solid central conductive tube or a solid central conductive tube; the inner diameter of the central conductive tube can be 35~70mm, or 40~60mm, or further 45~50mm; the outer diameter of the central conductive tube can be 45~90mm, or 50~80mm, or further 60~70mm. In this invention, the capacitor plates can be aluminum foil; the thickness of the adhesive-impregnated paper in adjacent capacitor plates can be 1.5~4mm or 2~3mm. In this invention, the impregnated paper is an insulating paper that has been impregnated and cured, and the insulating paper may include cellulose paper; the insulating paper may include crepe paper.

[0018] The moisture-proof paper-impregnated composite insulating bushing provided by this invention includes a moisture-proof reinforcing layer covering the outer surface of the paper-impregnated capacitor core. In this invention, the moisture-proof reinforcing material in the moisture-proof reinforcing layer includes at least one of glass fiber, polyester, and polyolefin. The polyester includes polyethylene terephthalate (PET); the polyolefin may include at least one of polypropylene (PP) and polyethylene (PE). This invention provides a moisture-proof reinforcing layer on the outer surface of the paper-impregnated capacitor core, effectively preventing moisture in the air during storage and trace amounts of moisture in the transformer oil during operation from penetrating the capacitor core and causing it to become damp, thus reducing its electrical performance. Simultaneously, it enhances its mechanical bending strength. The moisture-proof layer effectively solves the defects of paper-impregnated bushings, such as easy moisture absorption and weak bending resistance, extending the service life of the capacitor bushing and reducing the likelihood of equipment failure. It has excellent application prospects in electrical equipment.

[0019] In this invention, the linear density of the glass fiber can be 1100~2400 tax, or 1500~2000 tax, specifically 1100 tax, 1200 tax, 1300 tax, 1400 tax, 1500 tax, 1600 tax, 1700 tax, 1800 tax, 1900 tax, 2000 tax, 2100 tax, 2200 tax, 2300 tax, or 2400 tax. In this invention, the glass fiber can be used in the form of fibers or fiber cloth.

[0020] In this invention, the winding angle of the moisture-proof reinforcing material in the moisture-proof reinforcing layer (the angle between the moisture-proof reinforcing material and the axial direction) can be 40~90°, or 50~85°, or even 65~85°, specifically 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85° or 90°.

[0021] In this invention, when the moisture-proof reinforcing material is a mixture of at least one of polyester and polyolefin with glass fiber, the moisture-proof reinforcing material is a glass fiber reinforced polymer, and the glass fiber in the glass fiber reinforced polymer can be chopped glass fiber or glass fiber sand; the mass percentage of glass fiber in the glass fiber reinforced polymer can be 10-80%, or even 70-80%, specifically 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or 80%; the glass fiber reinforced polymer can include glass fiber sand reinforced polyester. In this invention, the moisture-proof reinforcing layer can include glass fiber cloth, glass fiber reinforced polymer nonwoven fabric, polymer nonwoven fabric, or polymer film. In this invention, the thickness of the moisture-proof reinforcing layer can be ≥5mm, and can further be 5-10mm, specifically 5mm, 8mm, 10mm, 12mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, or 30mm. This invention introduces a moisture-proof reinforcement layer on the outer surface of the impregnated paper capacitor core, which can effectively form a triple protective structure for the impregnated paper capacitor core, including moisture protection, increased bending strength, and impact resistance.

[0022] In this invention, when the outermost layer of the impregnated paper capacitor core is impregnated paper, a coupling agent coating may be further provided between the impregnated paper capacitor core and the moisture-proof reinforcing layer. In this invention, the coupling agent in the coupling agent coating may include at least one of silane coupling agents, titanate coupling agents, aluminate coupling agents, phosphate coupling agents, borate coupling agents, and organochromium complexes. In this invention, the silane coupling agent may include at least one of aminopropyltriethoxysilane (KH-550), γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH-560), vinyltriethoxysilane (A-151), γ-methacryloyloxypropyltrimethoxysilane (KH-570), γ-thiopropyltrimethoxysilane (KH-590), and dodecyltriethoxysilane (WD-20). In this invention, the titanate coupling agent may include monoalkoxy type titanate coupling agents, monoalkoxy pyrophosphate type, chelate type titanate coupling agents, and ligand type titanate coupling agents, specifically including at least one of isopropyltris(isostearoyl)titanate (TMC-101), isopropyltris(dioctylpyrophosphateoxy)titanate (TMC-201), di(pyrophosphatedioxy)oxyacetic acid ester titanium (TMC-311), and di(phosphatedioxy)ethylenediamine titanium (TMC-311). In this invention, the aluminate coupling agent may include at least one of aluminate, chelate aluminate, and polyaluminate, specifically including at least one of distearyloxyisopropyl aluminate (DL-411), chelate aluminate (ACA-M), and polyaluminate. In this invention, the phosphate coupling agent may include monophosphate and / or diphosphate, specifically including monophosphate (GQ-1) and / or diester (GQ-2). In this invention, the borate coupling agent may include triethanolamine borate and / or lauryl borate. In this invention, the organochromium complex may include an organochromium complex formed from an unsaturated organic acid and trivalent chromium ions, wherein the unsaturated organic acid may include methacrylic acid; the organochromium complex may specifically include a chromium chloride methacrylic acid complex.

[0023] The present invention also provides a method for preparing the moisture-proof adhesive-impregnated paper composite insulating sleeve described in the above technical solution.

[0024] In this invention, when the outermost layer of the impregnated paper capacitor core is impregnated paper, the preparation method includes method 1, method 2 or method 3.

[0025] In this invention, method 1 includes the following steps: S11. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube, impregnate with adhesive (referred to as the first impregnation) and then cure (referred to as the first curing) to obtain the adhesive-impregnated paper capacitor core. S12. The moisture-proof reinforcing material is wet-coated onto the outer surface of the impregnated paper capacitor core and cured (referred to as the second curing) to obtain the moisture-proof impregnated paper composite insulating sleeve.

[0026] Unless otherwise specified, the materials and equipment used in this invention are all commercially available products in the field.

[0027] In this invention, all the insulating paper and capacitor plates are alternately wound around the outer surface of the central conductive tube, followed by a first impregnation with resin and a first curing process, to obtain a resin-impregnated paper capacitor core.

[0028] In this invention, the alternating winding process may further include drying the core obtained from the alternating winding (referred to as the first drying). In this invention, the first drying may include vacuum drying. The temperature of the vacuum drying may be 90-110°C, or 95-106°C, or even 98-103°C. This invention does not have a specific limitation on the drying time; drying to a constant weight is sufficient. The vacuum degree of the vacuum drying may be 20-40 Pa, or 25-35 Pa, or even 30 Pa. The vacuum drying may be carried out in a vacuum oven. In this invention, the purpose of the first drying is to completely remove moisture and volatiles from the insulating paper.

[0029] In this invention, the adhesive used for the first impregnation may include an epoxy resin and a curing agent; the epoxy resin has a temperature resistance >120℃; the curing agent may include methyltetrahydrophthalic anhydride and / or methylhexahydrophthalic anhydride, and the mass ratio of the epoxy resin to the curing agent may be 1:0.85~1, specifically 1:0.85, 1:0.9, 1:0.95, or 1:1. In this invention, the impregnation speed may be 2~3L / min, or even 2.5L / min; the impregnation temperature may be 60±3℃; the first impregnation is vacuum impregnation, and the vacuum degree of the vacuum impregnation may be 100±3Pa.

[0030] In this invention, the first curing process can be programmed curing, which may include sequentially performing the following: curing at 55-65°C for 12-48 hours, curing at 65-75°C for 10-15 hours, curing at 75-85°C for 2-4 hours, curing at 85-95°C for 2-4 hours, curing at 95-105°C for 25-35 hours, and curing at 115-125°C for 15-25 hours; specifically, curing at 60°C for 12 hours, curing at 70°C for 12 hours, curing at 80°C for 3 hours, curing at 90°C for 3 hours, curing at 100°C for 3 hours, and curing at 110°C for 30 hours. In this invention, during the first curing process, the central conductive tube, insulating paper, capacitor plates, and adhesive are firmly bonded together as a whole.

[0031] After obtaining the impregnated paper capacitor core, the present invention wet-coates the outer surface of the impregnated paper capacitor core with a moisture-proof reinforcing material and cures it (referred to as the second curing) to obtain the moisture-proof impregnated paper composite insulating sleeve.

[0032] In this invention, the process before wet coating further includes: preheating the resin-impregnated paper capacitor core, coating its outer surface with a coupling agent, and then drying it (referred to as the second drying). In this invention, the preheating temperature can be 60-80°C, or 65-70°C, or even 70°C. In this invention, the second drying may include air drying. In this invention, when the moisture-proof reinforcing material is glass fiber, the winding angles of the hot-wet spiral winding and circumferential winding can be 40-90°, or 50-85°, specifically 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, or 90°. In this invention, the single-layer thickness of the resin-impregnated moisture-proof reinforcing material can be 0.1-0.3 mm, specifically 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, or 0.3 mm.

[0033] In this invention, the wet coating process can include wet winding, adhesive bonding, or vacuum impregnation. Specifically, when wet winding is used, it includes: impregnating the moisture-proof reinforcing material with adhesive and then wrapping it around the outer surface of the adhesive-impregnated paper capacitor core. When adhesive bonding is used, it includes: applying adhesive to the inner surface of the moisture-proof reinforcing material and / or applying adhesive to the outer surface of the adhesive-impregnated paper capacitor core, and then bonding the two together; the bonding temperature can be room temperature. When vacuum impregnation is used, it includes: dry winding the moisture-proof reinforcing material around the outer surface of the adhesive-impregnated paper capacitor core and then vacuum impregnating it in the adhesive. In this invention, the types of adhesives used in the wet winding, adhesive bonding, or vacuum impregnation are the same as those used in the preparation of the adhesive-impregnated paper capacitor core in Method 1, and will not be repeated here. This invention does not specifically limit the wet coating process; it only requires that the moisture-proof reinforcing material be firmly bonded to the outer surface of the adhesive-impregnated paper capacitor core. In this invention, the wet winding may include wet spiral winding or wet circumferential winding; the wet coating may be performed on a CNC winding machine.

[0034] In this invention, the second curing can be a programmed curing process, which may include: curing at 70~90℃ for 1~3 hours, curing at 110~130℃ for 15~25 hours, specifically curing at 70~90℃ for 1~3 hours and curing at 110~130℃ for 15~25 hours; or specifically curing at 80℃ for 2 hours and curing at 120℃ for 20 hours, specifically curing at 80℃ for 2 hours and curing at 120℃ for 20 hours; the second curing can be carried out in an oven.

[0035] In this invention, method 2 includes the following steps: S21. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube, impregnate with adhesive and then cure to obtain the adhesive-impregnated paper capacitor core. The moisture-proof reinforcing material is processed into moisture-proof reinforcing material pipes; S22. Apply adhesive to the outer surface of the impregnated paper capacitor core and / or the inner surface of the moisture-proof reinforcing material tube, then assemble the impregnated paper capacitor core and the moisture-proof reinforcing material tube, and cure (referred to as the third curing) to obtain the moisture-proof impregnated paper composite insulating sleeve.

[0036] In this invention, all insulating paper and capacitor plates are alternately wound around the outer surface of the central conductive tube, impregnated with resin, and then cured to obtain a resin-impregnated paper capacitor core. In this invention, the preparation method of the resin-impregnated paper capacitor core can be the same as that in Method 1, and will not be repeated here.

[0037] This invention processes moisture-proof reinforcing materials into moisture-proof reinforcing material tubes. In this invention, the moisture-proof reinforcing material tube includes a wound moisture-proof reinforcing material tube or a pultruded moisture-proof reinforcing material tube. This invention does not specifically limit the preparation method of the wound moisture-proof reinforcing material tube or the pultruded moisture-proof reinforcing material tube; any preparation method of wound tubes or pultruded tubes well known to those skilled in the art can be used.

[0038] After obtaining the impregnated paper capacitor core and the moisture-proof reinforcing material tube, the present invention coats the outer surface of the impregnated paper capacitor core and / or the inner surface of the moisture-proof reinforcing material tube with adhesive, then assembles the impregnated paper capacitor core and the moisture-proof reinforcing material tube, and then cures it to obtain the moisture-proof impregnated paper composite insulating sleeve.

[0039] In this invention, the moisture-proof reinforced material pipe undergoes a roughening and cleaning process on its inner wall before use. The cleaning process includes cleaning with lint-free paper and / or cleaning with an ethanol-water solution. The volume fraction of the ethanol-water solution can be 50-95%, 60-95%, or even 80-90%.

[0040] In this invention, before coating the outer surface of the impregnated paper capacitor core with the adhesive, the process may further include: preheating the impregnated paper capacitor core, coating the outer surface with a coupling agent, and then drying (referred to as the third drying); and / or preheating the moisture-proof reinforcing material tube before coating the inner surface with the adhesive, coating the inner wall with a coupling agent, and then drying (referred to as the fourth drying). In this invention, the preheating temperature of the impregnated paper capacitor core and the moisture-proof reinforcing material tube can be independently 60~80℃, or 65~75℃, or further 70℃. In this invention, the third drying may include air drying. In this invention, the fourth drying may include air drying. In this invention, the optional type of adhesive is the same as the optional type of adhesive used in the preparation of the impregnated paper capacitor core in method 1, and will not be repeated here.

[0041] In this invention, the difference between the outer diameter of the impregnated paper capacitor core and the inner diameter of the moisture-proof reinforcing material tube (i.e., the assembly gap width) can be 0.1~1mm, specifically 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm.

[0042] This invention allows for the inspection of the dimensions of the impregnated paper capacitor core and the moisture-proof reinforcing material tube before assembly, which can improve the product qualification rate and reduce material costs.

[0043] In this invention, the assembly may include: placing the moisture-proof reinforcing material tube vertically, vertically inserting the paper-impregnated capacitor core into the moisture-proof reinforcing material tube, and sealing one end of the paper-impregnated capacitor core and the moisture-proof reinforcing material tube. In this invention, the sealing process may be a radial seal using a sealing element between one end of the core and the moisture-proof reinforcing material tube, or a threaded seal.

[0044] In this invention, the third curing process includes thermal curing or room temperature curing. The conditions for thermal curing can be the same as those for the first curing process, and will not be repeated here. The room temperature curing time can be 20-40 hours, or 22-30 hours, specifically 24 hours. After the third curing, the impregnated paper capacitor core and the moisture-proof reinforcing material tube form a single unit.

[0045] In this invention, step S22 in method 2 is replaced by: S22', assembling the impregnated paper capacitor core with the moisture-proof reinforcing material tube, filling the assembly gaps with adhesive, then assembling the impregnated paper capacitor core with the moisture-proof reinforcing material tube, and curing to obtain the moisture-proof impregnated paper composite insulating sleeve. In this invention, the moisture-proof reinforcing material tube undergoes roughening and cleaning of its inner wall before use. In this invention, the cleaning includes cleaning with lint-free paper and / or cleaning with an ethanol aqueous solution; the volume fraction of the ethanol aqueous solution can be 50-95%, or 60-95%, or further 80-90%. In this invention, the assembly process further includes: preheating the impregnated paper capacitor core, coating the outer surface with a coupling agent, and then drying (referred to as the fifth drying), and / or preheating the moisture-proof reinforcing material tube, coating the inner wall with a coupling agent, and then drying (referred to as the sixth drying). In this invention, the preheating temperature of the impregnated paper capacitor core and the moisture-proof reinforcing material tube can be independently 60~80℃, or 65~75℃, or even 70℃. In this invention, the fifth drying step can include air drying. In this invention, the sixth drying step can include air drying. In this invention, the optional type of adhesive is the same as that used in the preparation of the impregnated paper capacitor core in method 1, and will not be repeated here. In this invention, the assembly can be the same as the assembly in step S22, and will not be repeated here.

[0046] In this invention, method 3 includes the following steps: S31. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube to obtain an uncured, resin-impregnated capacitor core. The moisture-proof reinforcing material is processed into a moisture-proof reinforcing material tube with one end closed (for use as a casting mold); S32. Assemble the uncured glue-impregnated capacitor core with the moisture-proof reinforcing material tube, and cure it after impregnation (referred to as the fourth curing) to obtain the moisture-proof glue-impregnated paper composite insulating sleeve.

[0047] This invention involves alternately winding all the insulating paper and capacitor plates around the outer surface of a central conductive tube to obtain an uncured, resin-impregnated capacitor core. In this invention, the difference between the preparation method of the uncured, resin-impregnated capacitor core and the preparation method of the resin-impregnated paper capacitor core in Method 1 lies only in omitting the first resin impregnation and the first curing.

[0048] This invention processes a moisture-proof reinforcing material into a moisture-proof reinforcing material tube with one end closed. In this invention, the moisture-proof reinforcing material tube includes a wound moisture-proof reinforcing material tube or a pultruded moisture-proof reinforcing material tube. This invention does not impose any particular limitation on the preparation method of the wound moisture-proof reinforcing material tube or the pultruded moisture-proof reinforcing material tube; any preparation method well-known to those skilled in the art for wound tube or pultruded tube preparation can be used. The moisture-proof reinforcing material tube with one end closed prepared by this invention can be used as a casting mold for preparing impregnated paper capacitor cores.

[0049] After obtaining the uncured resin-impregnated capacitor core and the moisture-proof reinforcing material tube, the present invention assembles the uncured resin-impregnated capacitor core and the moisture-proof reinforcing material tube, and then cures it after resin impregnation to obtain the moisture-proof resin-impregnated paper composite insulating sleeve.

[0050] In this invention, the pre-assembly process may further include: preheating the moisture-proof reinforcing material tube, coating the inner wall with a coupling agent, and then drying (referred to as the seventh drying). In this invention, the preheating temperature may be independently 60-80°C, or 65-75°C, or even 70°C. In this invention, the seventh drying may include air drying.

[0051] This invention allows for the inspection of the dimensions of the uncured, impregnated capacitor core and the moisture-proof reinforcing material tube before assembly, which can improve the product qualification rate and reduce material costs.

[0052] In this invention, the assembly process further includes drying the assembled material (referred to as the eighth drying). The conditions for the eighth drying can be the same as those for the first drying, and will not be described again here.

[0053] In this invention, the type of adhesive and the conditions for the fourth curing can be the same as those for the type of adhesive and the conditions for the first curing in the preparation method of the impregnated paper capacitor core in Method 1, and will not be repeated here. After the fourth curing, the uncured impregnated capacitor core forms an integral unit with the moisture-proof reinforcing material tube.

[0054] In this invention, when the outermost layer of the impregnated paper capacitor core is a capacitor plate, the preparation method includes method 4, which includes the following steps: alternately winding all the insulating paper and capacitor plates around the outer surface of the central conductive tube, covering the outer surface of the outermost capacitor plate (i.e., the end screen electrode) with a moisture-proof reinforcing material, impregnating with resin and then curing to obtain the moisture-proof impregnated paper composite insulating sleeve.

[0055] In this invention, the coating includes dry circumferential winding or spiral winding; the coating includes a roll or a strip, the angle of which can be 40~90°, 50~85°, or even 65~85°, specifically 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, or 90°; the first coating can be performed on a CNC winding machine.

[0056] In this invention, before the impregnation, the process further includes drying the core after it is coated with moisture-proof reinforcing material (referred to as the ninth drying). The drying conditions can be the same as those of the first drying, and will not be described again here.

[0057] In this invention, the other preparation conditions of the moisture-proof impregnated paper composite insulating sleeve can be the same as those of the impregnated paper capacitor core in method 1, and will not be described in detail here.

[0058] This invention also provides the application of the moisture-proof adhesive-impregnated paper composite insulating bushing described in the above-described technical solutions, or the moisture-proof adhesive-impregnated paper composite insulating bushing prepared by the above-described technical solutions, in electrical equipment. In this invention, the electrical equipment may include 10kV~1100kV AC adhesive-impregnated paper dry-type transformer bushings, adhesive-impregnated paper dry-type AC through-wall bushings, adhesive-impregnated paper AC GIS bushings, ±10~±1100kV adhesive-impregnated paper DC through-wall bushings, or adhesive-impregnated paper DC valve-side transformer bushings. The moisture-proof paper-impregnated composite insulating bushing provided by this invention has excellent moisture-proof performance and mechanical strength. It forms a triple protective structure on the surface of the paper-impregnated capacitor core, which provides moisture protection, increased bending strength, and impact resistance. It has great application prospects in electrical equipment, especially 10kV~1100kV AC paper-impregnated dry-type transformer bushings, paper-impregnated dry-type AC through-wall bushings, paper-impregnated AC GIS bushings, ±10~±1100kV paper-impregnated DC through-wall bushings, or paper-impregnated DC valve-side transformer bushings.

[0059] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, of the moisture-proof impregnated paper composite insulating sleeve provided by the present invention, its preparation method, and its application, should not be construed as limiting the scope of protection of the present invention.

[0060] In the following examples, the adhesive used for impregnation consisted of: 100g of epoxy resin (Aradur series resin CY5868) and 85g of curing agent (ARADUR® HY 5868). The epoxy resin adhesive had a temperature resistance >120°C. The moisture-proof reinforcing material was one or more of fiberglass cloth, polyethylene terephthalate, polyethylene, and polypropylene.

[0061] Example 1 Method 1 Taking the production of 126kV transformer bushings as an example All the insulating paper (cellulose crepe paper) and capacitor plates (aluminum foil) are precisely and alternately wound around the outer surface of the central aluminum tube (inner diameter 35mm, outer diameter 45mm); the resulting core is placed in a vacuum oven and vacuum dried to constant weight at 100±10℃ and 30±10Pa, then placed in a vacuum drying jar for vacuum impregnation and programmed curing to obtain the paper-impregnated capacitor core (see...). Figure 3 The process involves wrapping a layer of aluminum foil around a 2mm thick cellulose crepe paper. Vacuum impregnation conditions are as follows: adhesive temperature 60±3℃, impregnation rate 2.5±0.5L / min, vacuum degree 100±2Pa, and epoxy resin amount sufficient to completely fill all gaps between the insulating paper layers. The curing procedure is as follows: 12h at 60℃, 12h at 70℃, 3h at 80℃, 3h at 90℃, 3h at 100℃, and 30h at 110℃. The outermost layer of the impregnated paper capacitor core is insulating paper.

[0062] Moisture-proof reinforcing material is impregnated in epoxy resin at room temperature to obtain impregnated moisture-proof reinforcing material. The impregnated paper capacitor core is mounted on a CNC winding machine. The surface of the impregnated paper capacitor core is preheated to 70±10℃. A silane coupling agent KH-550 is evenly brushed onto the outer surface and then dried. The impregnated moisture-proof reinforcing material is then wet-wound circumferentially or spirally onto the outer surface until the surface winding diameter increases by 15mm. Curing is then performed to obtain a moisture-proof impregnated paper composite insulating sleeve. The curing procedure is 2 hours at 80℃ and 20 hours at 120℃, specifically 2 hours at 80℃ and 20 hours at 120℃.

[0063] Example 2 Method 2 Taking the production of 126kV transformer bushings as an example The impregnated paper capacitor core was prepared according to the method in Example 1.

[0064] Based on the dimensions of the impregnated paper capacitor core, produce moisture-proof reinforced spiral tubes or moisture-proof reinforced pultruded tubes. The tube wall thickness is 12mm, and the inner wall of the tube is roughened. Clean the inner surface of the composite material tube with lint-free paper and 95% ethanol aqueous solution, preheat to 70±10℃, and evenly brush the outer surface with silane coupling agent KH-550 before drying. After machining the impregnated paper capacitor core and the moisture-proof reinforced tube, check the dimensions. The difference between the outer diameter of the impregnated paper capacitor core and the inner diameter of the moisture-proof reinforced tube should be 0.1~1mm.

[0065] Epoxy resin is applied to the outer surface of the paper-impregnated capacitor core and the inner wall of the moisture-proof reinforcing material tube. The moisture-proof reinforcing material tube is placed vertically, and the paper-impregnated capacitor core is placed vertically into the moisture-proof reinforcing material tube. The bottom part of the paper-impregnated capacitor core and the moisture-proof reinforcing material tube are sealed. The tube is then cured at 60℃ for 12 hours, at 70℃ for 12 hours, at 80℃ for 3 hours, at 90℃ for 3 hours, at 100℃ for 3 hours, and at 110℃ for 30 hours, or left to stand at room temperature for 12 hours to obtain a moisture-proof paper-impregnated composite insulating sleeve.

[0066] Example 3 Method 3 Taking the production of 126kV transformer bushings as an example All the insulating paper (cellulose crepe paper) and capacitor plates (aluminum foil) are precisely and alternately wound around the outer surface of a central aluminum tube (inner diameter 35mm, outer diameter 45mm); this results in an uncured, resin-impregnated capacitor core. A layer of aluminum foil is wound around the cellulose crepe paper when the paper is 2mm thick.

[0067] Based on the dimensions of the impregnated paper capacitor core, produce a closed-end moisture-proof reinforcing material spiral tube or a moisture-proof reinforcing material pultruded tube as a mold. The tube wall thickness is 5mm, and the inner wall of the tube is processed into a rough surface. Clean the inner surface of the composite material tube with dust-free paper and 95% ethanol aqueous solution, heat it to 70±10℃, and brush the outer surface evenly with silane coupling agent KH-550 and then let it dry.

[0068] After the uncured resin-impregnated capacitor core and the moisture-proof reinforcing material tube are machined, check their dimensions. The difference between the outer diameter of the uncured resin-impregnated capacitor core and the inner diameter of the moisture-proof reinforcing material tube is 0.01~0.1mm.

[0069] The moisture-proof reinforcing material tube was placed vertically, and the uncured, resin-impregnated capacitor core was vertically placed inside the tube. The tube was then placed in a vacuum drying chamber and vacuum-dried to constant weight at 100±10℃ and 30±10Pa. Vacuum impregnation with epoxy resin followed by curing yielded a moisture-proof resin-impregnated paper composite insulating sleeve. The vacuum impregnation conditions were: epoxy resin temperature 60±3℃, impregnation rate 2.5±0.5L / min, and vacuum degree 100±2Pa. The curing procedure was as follows: curing at 60℃ for 12 hours, at 70℃ for 12 hours, at 80℃ for 3 hours, at 90℃ for 3 hours, at 100℃ for 3 hours, and at 110℃ for 30 hours.

[0070] Example 4 Method 4 Taking the production of 126kV transformer bushings as an example All insulating paper (cellulose crepe paper) and capacitor plates (aluminum foil) are precisely and alternately wound around the outer surface of the central aluminum tube (inner diameter 35mm, outer diameter 45mm). After the outermost layer of the final plate is wound, a moisture-proof reinforcing material (thickness ≥5.0mm) is dry-wound circumferentially or spirally wound onto the outer layer of the plate. The winding method is strip winding or whole roll. After winding, the wound core is placed in a vacuum drying chamber and vacuum-dried to constant weight at 100±10℃ and 30±10Pa. It is then vacuum impregnated and cured according to a program to obtain a moisture-proof resin-impregnated paper composite insulating sleeve. A layer of aluminum foil is wound around the cellulose crepe paper when the thickness is 1.5~2mm. The vacuum impregnation conditions are: epoxy resin temperature 60±3℃, impregnation speed 2.5±0.5L / min, vacuum degree 100±2Pa, and the amount of epoxy resin used is sufficient to completely fill all gaps between the insulating paper layers. The curing process is as follows: cure at 60℃ for 12 hours, cure at 70℃ for 12 hours, cure at 80℃ for 3 hours, cure at 90℃ for 3 hours, cure at 100℃ for 3 hours, and cure at 110℃ for 30 hours.

[0071] Test Example 1 1. Mechanical strength The mechanical strength of the impregnated paper capacitor core prepared in Example 1 and the moisture-proof impregnated paper composite insulating bushing (126kV transformer bushing, the moisture-proof reinforcing material is glass fiber cloth) prepared in Examples 1 to 4 were tested according to GB / T4109.

[0072] Figure 4 This is a deformation contour map comparing the differences in the maximum horizontal displacement when a horizontal force of 2000N is applied to the upper part of the resin-impregnated paper capacitor core prepared in Example 1. Figure 5 Deformation cloud diagrams comparing the differences in maximum horizontal displacement when a horizontal force of 2000N is applied to the upper part of the moisture-proof adhesive-impregnated paper composite insulating sleeve prepared in Example 4. Figures 4-5 It can be seen that when a horizontal thrust of 2000N is applied to the upper part, the displacement of the impregnated paper capacitor core is 11.06mm, while the displacement of the moisture-proof impregnated paper composite insulating sleeve is only 3.4mm. This indicates that the bending strength of the moisture-proof impregnated paper composite insulating sleeve after adding a moisture-proof reinforcing layer to the outer surface is significantly improved compared to the existing impregnated paper capacitor core. This demonstrates that the moisture-proof impregnated paper composite insulating sleeve prepared by this invention has excellent bending performance.

[0073] Figure 6 These are the deformation contour maps of the paper-impregnated capacitor core prepared in Example 1 under different radial forces when the maximum displacement is 10 mm. Figure 7 The images show the deformation contours of the moisture-proof adhesive-impregnated paper composite insulating sleeve prepared in Example 4 under different radial forces when the maximum displacement is 10 mm. Figures 6-7It is known that when a horizontal force is applied to the top of the impregnated paper capacitor core, the force required to achieve a maximum displacement of 10 mm is 1900 N, while the force required for the moisture-proof impregnated paper composite insulating sleeve to achieve a maximum displacement of 10 mm is as high as 5500 N. This indicates that the bending strength of the moisture-proof impregnated paper composite insulating sleeve, after adding a moisture-proof reinforcing layer to the outer surface, is significantly improved compared to the existing impregnated paper capacitor core.

[0074] Mechanical strength: The axial bending strength of the moisture-proof impregnated paper composite insulating sleeves prepared in Examples 1-4 is 5000-5500N, which is significantly improved compared with the axial bending strength (2000N) of the impregnated paper capacitor core prepared in Example 1.

[0075] 2. Power frequency withstand voltage test The moisture-proof adhesive-impregnated paper composite insulating sleeves prepared in Examples 1-4 were tested according to GB / T4109-2022.

[0076] With a power frequency withstand voltage of 255kV / 60min, the moisture-proof impregnated paper composite insulating bushings prepared by various moisture-proof reinforcing materials in Examples 1-4 all showed no field strike or flashover phenomenon.

[0077] 3. Moisture-proof performance test The impregnated paper capacitor core prepared in Example 1 and the moisture-proof impregnated paper composite insulating sleeves prepared in Examples 1-4 (the moisture-proof reinforcing material is glass fiber cloth) were stored in an environment of 25°C, 101.3 kPa and 75% relative humidity for 3 days. The test results are shown in Table 1.

[0078] Table 1. Moisture-proof test results of impregnated paper capacitor cores and moisture-proof impregnated paper composite insulating sleeves.

[0079] As shown in Table 1, the dielectric loss of the moisture-proof paper-impregnated composite insulating sleeve prepared by this invention remained essentially unchanged before and after the moisture-proof performance test, while the dielectric loss of the paper-impregnated capacitor core decreased significantly after the moisture-proof performance test. The moisture permeability decreased to 1 / 5 of the original product.

[0080] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A moisture-proof adhesive-impregnated paper composite insulating sleeve, comprising an adhesive-impregnated paper capacitor core and a moisture-proof reinforcing layer covering the outer surface of the adhesive-impregnated paper capacitor core; The moisture-proof reinforcing material in the moisture-proof reinforcing layer includes at least one of glass fiber, polyester and polyolefin, wherein the polyester includes polyethylene terephthalate. The impregnated paper capacitor core includes a central conductive tube, impregnated paper, and capacitor plates; the impregnated paper and capacitor plates alternately cover the outer surface of the central conductive tube from the inside out, and the outermost layer of the impregnated paper capacitor core is either impregnated paper or capacitor plates.

2. The moisture-proof adhesive-impregnated paper composite insulating sleeve according to claim 1, characterized in that, The polyolefin includes at least one of polypropylene and polyethylene.

3. The moisture-proof adhesive-impregnated paper composite insulating sleeve according to claim 1, characterized in that, The winding angle of the moisture-proof reinforcing material in the moisture-proof reinforcing layer is 40~90°.

4. The moisture-proof adhesive-impregnated paper composite insulating sleeve according to any one of claims 1 to 3, characterized in that, The thickness of the moisture-proof reinforcement layer is ≥5mm.

5. The moisture-proof adhesive-impregnated paper composite insulating sleeve according to any one of claims 1 to 3, characterized in that, When the outermost layer of the impregnated paper capacitor core is impregnated paper, a coupling agent coating is also provided between the impregnated paper capacitor core and the moisture-proof reinforcement layer.

6. The moisture-proof adhesive-impregnated paper composite insulating sleeve according to claim 5, characterized in that, The coupling agent in the coupling agent coating includes at least one of silane coupling agents, titanate coupling agents, aluminate coupling agents, phosphate coupling agents, borate coupling agents, and organochromium complexes.

7. The method for preparing the moisture-proof adhesive-impregnated paper composite insulating sleeve according to any one of claims 1 to 6, When the outermost layer of the impregnated paper capacitor core is impregnated paper, the preparation method includes method 1, method 2 or method 3; Method 1 includes the following steps: S11. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube, impregnate with adhesive and then cure to obtain the adhesive-impregnated paper capacitor core. S12. The moisture-proof reinforcing material is wet-coated onto the outer surface of the impregnated paper capacitor core and cured to obtain the moisture-proof impregnated paper composite insulating sleeve. Method 2 includes the following steps: S21. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube, impregnate with adhesive and then cure to obtain the adhesive-impregnated paper capacitor core. The moisture-proof reinforcing material is processed into moisture-proof reinforcing material pipes; S22. Apply adhesive to the outer surface of the paper-impregnated capacitor core and / or the inner surface of the moisture-proof reinforcing material tube, then assemble the paper-impregnated capacitor core and the moisture-proof reinforcing material tube, and cure to obtain the moisture-proof paper-impregnated composite insulating sleeve. Method 3 includes the following steps: S31. Alternately wind all the insulating paper and capacitor plates around the outer surface of the central conductive tube to obtain an uncured, resin-impregnated capacitor core. The moisture-proof reinforcing material is processed into a moisture-proof reinforcing material tube with one end closed; S32. Assemble the uncured glue-impregnated capacitor core with the moisture-proof reinforcing material tube, and cure it after glue impregnation to obtain the moisture-proof glue-impregnated paper composite insulating sleeve. When the outermost layer of the impregnated paper capacitor core is a capacitor plate, the preparation method includes method 4, which includes the following steps: All the insulating paper and capacitor plates are alternately wound around the outer surface of the central conductive tube. Moisture-proof reinforcing material is coated on the outer surface of the outermost capacitor plate. After impregnation with resin, the material is cured to obtain the moisture-proof resin-impregnated paper composite insulating sleeve.

8. The preparation method according to claim 7, characterized in that, In both methods 1 and 2, after alternating winding, the process further includes drying the core obtained by alternating winding. In step S12, before the wet coating, the process further includes: preheating the glue-impregnated paper capacitor core, coating the outer surface with a coupling agent, and then drying it; the wet coating includes wet winding, glue bonding, or vacuum impregnation. In step S22, before coating the outer surface of the paper-impregnated capacitor core with adhesive, the process further includes: preheating the paper-impregnated capacitor core, coating the outer surface with coupling agent and then drying it, and / or preheating the moisture-proof reinforcing material tube before coating the inner surface of the moisture-proof reinforcing material tube with adhesive, coating the inner wall with coupling agent and then drying it. In step S32, the process before assembly further includes: preheating the moisture-proof reinforcing material tube, coating the inner wall with a coupling agent, and then drying it; the process after assembly further includes: drying the assembled material. Method 4 further includes drying the core after it has been coated with moisture-proof reinforcing material before impregnation.

9. The preparation method according to claim 7 or 8, characterized in that, Step S22 is replaced by: S22' Assemble the impregnated paper capacitor core with the moisture-proof reinforcing material tube, fill the assembly gap with adhesive, then assemble the impregnated paper capacitor core with the moisture-proof reinforcing material tube, and cure to obtain the moisture-proof impregnated paper composite insulating sleeve. The assembly process described in step S22' further includes: preheating the moisture-proof reinforcing material tube, coating the inner wall with a coupling agent and then drying it, and / or preheating the impregnated paper capacitor core, coating the outer surface with a coupling agent and then drying it.

10. The application of the moisture-proof impregnated paper composite insulating sleeve according to any one of claims 1 to 6 or the moisture-proof impregnated paper composite insulating sleeve prepared by the preparation method according to any one of claims 7 to 9 in electrical equipment.

Images