Method, kit and gas insulated electrical device for sealing a gas insulated electrical device

Abstract

The present invention relates to a method for sealing a section (110) of a gas-insulated electrical device (100) (e.g., a device (100) configured as a gas-insulated switch or a gas-insulated line), particularly for improving the lifespan of the device (100). The method comprises the steps of: surface treating (30) at least the outer surface (122) of the section (110); applying (40) an adhesive (2) to the outer surface (122); arranging (50) a flexible, flat material (4) on the outer surface (122); and curing (60) the adhesive (2). The invention also relates to a kit (1) and a gas-insulated electrical device (100).

Description

Technical Field

[0001] This disclosure relates to a method for sealing gas-insulated electrical equipment. This disclosure also relates to a kit configured to perform the method and the gas-insulated electrical equipment. Background Technology

[0002] Gas-insulated electrical equipment typically contains an insulating gas near the electrically conductive components. This gas is typically contained within a closed volume or circuit inside the equipment. Over time, leaks can occur, such as due to material aging and / or corrosion, causing the insulating gas to escape from the equipment. Therefore, maintaining the seal of gas-insulated electrical equipment and repairing leaks are concerns. Providing more leak-proof equipment is also a concern.

[0003] JP 5 075785 B2 describes the repair of gas leaks caused by deterioration of the flange joint surface of a vessel without interrupting electrification.

[0004] JP 5 764389 B2 describes a repair method for repairing gas leaks from containers containing insulating gases. Summary of the Invention

[0005] Therefore, the aim is to provide solutions for gas-insulated electrical equipment to improve lifespan, operating costs, and maintenance costs. In particular, the aim is to avoid or reduce the drawbacks of known solutions.

[0006] These objectives are achieved through the features of the independent claims. Preferred embodiments are described in detail in the dependent claims, the specification, and the drawings.

[0007] This objective is achieved in particular by a method for sealing sections of gas-insulated electrical equipment, the method comprising the following steps: At least the outer surface of the segment is surface-treated, wherein the surface treatment includes cleaning the outer surface and / or roughening the outer surface, and in particular, the outer surface may be a radial outer surface and / or an axial outer surface. Apply the adhesive to the outside. A flexible flat material is disposed on the outside, wherein the flexible flat material is configured for being bonded, impregnated, and / or penetrated by an adhesive to form a composite material with the adhesive and / or thereby form a composite material with the adhesive. For example, the flexible flat material may be disposed on the outside together with the adhesive, and / or the flexible flat material may be configured for being bonded to the outside by means of an adhesive, and Allow the adhesive to cure.

[0008] In particular, flexible flat materials include molded prepregs or are molded prepregs.

[0009] In other words, specifically, a repair method is proposed in which a leaking area of ​​a gas-insulated electrical device is sealed essentially based on the following steps. First, the surface of the leaking area is treated to remove debris, dirt, corrosion, etc., particularly coatings and / or paints. Treatment of the leaking area can alternatively or additionally be used to increase surface roughness, for example, to increase the adhesion of the adhesive to the leaking area. Subsequently, an adhesive is applied to the cleaned / roughened leaking area. The adhesive can be liquid and / or viscous. The adhesive can be applied alone or in combination with a flexible material (such as a strip material that has been or is being impregnated with the adhesive and / or molding prepreg and / or coated with the adhesive and / or molding prepreg). The flexible material can also be placed on top of the adhesive. The flexible material can be bonded to and / or impregnated with the adhesive to subsequently form a composite material, or the flexible material can have already been impregnated with or attached to the adhesive to form a composite material, particularly wherein the adhesive can be cured after being placed on the leaking area and / or after the flexible material is placed on the adhesive. The adhesive can be cured, for example, by means of time, chemical reaction, and / or temperature. Therefore, leakage in the leaking area can be prevented.

[0010] For example, the prior art of JP 5 075785 B2 does not explicitly foreshadow surface treatment including cleaning or roughening the exterior, wherein the flexible flat material includes or is a molded prepreg. In the absence of corresponding implications in the prior art, the various features involve inventive steps.

[0011] This invention advantageously provides gas-insulated electrical equipment that can be handled in the event of a leak, to reduce, prevent, or remove the leak. The invention can also be considered a preventative measure for sections to avoid or reduce the risk of leakage. A sealing composite housing is provided on this section.

[0012] This invention provides a method that can be widely and flexibly applied to gas-insulated electrical equipment, wherever a section of the equipment leaks or is likely to leak. This invention avoids cost-intensive replacement of components, gaskets, etc. This invention can be applied outdoors worldwide and / or in various climate regions. Furthermore, this invention can be easily applied to outdoor environments.

[0013] It may be possible to remove the seal provided by the present invention without damaging the section. This even provides the option to repeat the method.

[0014] This invention avoids the need to disassemble or shut down gas-insulated electrical equipment because it allows operation to be performed solely or primarily from the outside of the equipment. Therefore, power outages are not required when using the method of this invention. No handling of the insulating gas is necessary.

[0015] This invention identifies that many gas-insulated electrical equipment or installations may face gas leakage problems at certain sections, particularly at flanges, such as those included in gas-insulated switchgear (GIS) or gas-insulated line (GUL) mounting bases. This invention provides a flexible and easy method for sealing these sections or flanges, where existing third-party solutions are expensive and inflexible when dealing with sealing flanges of different sizes. This invention provides a cost-effective, outdoor-use flange sealing solution applicable to GIS / GIL flanges of varying diameters, while preventing gas leakage and achieving the same airtightness as new GIS during operation (without venting or opening the flange).

[0016] Flanges in gas-insulated electrical equipment are typically sealed with gaskets or annular gaskets (especially O-rings), which may be additionally protected by grooves filled with grease. The grooves may be at least partially formed on the flange, for example, at the front end of the flange. The grooves may have an annular shape corresponding to the gasket. The flange may include holes, such as threaded holes, to fill the grooves with grease. This grease isolates the O-ring from environmental influences and thus protects the O-ring from environmental impacts. During prolonged operation, heat, rain, and other influences cause the grease to be washed away. If the grooves are not refilled, corrosion may occur on the surface of the O-ring grooves and / or the O-ring itself may become embrittled. This ultimately leads to leaks that the present invention can effectively prevent.

[0017] The aforementioned details, advantages, and effects can be further improved by means of one or more of the other preferred features described herein.

[0018] Sealing involves closing a path or gap for insulating gases. Sealing is typically performed using materials configured for sealing and / or blocking. Sealing involves gaseous or fluid sealing of components or sections. Leakage paths can be sealed by blocking them, for example, when two rigid bodies (such as pipes) are connected using the gasket, the leakage path may eventually appear in the area of ​​the gasket. Blocking can be performed using an adhesive placed on and / or in the leakage path and allowed to cure. The problem with sealing leakage paths using this simple method is that the pressure of the insulating gas can eventually cause leakage again. Therefore, more sophisticated methods should be used to seal sections, such as the methods presented herein.

[0019] Sections of gas-insulated electrical equipment typically involve areas or regions of that section, particularly including flanges and / or flange connection structures. The section typically includes rigid components or assemblies, particularly gaskets configured to seal the section. The section has outer surfaces or external surfaces, particularly multiple outer surfaces or external surfaces. Outer surfaces may include radial outer surfaces, and alternatively or additionally include axial outer surfaces. Outer surfaces are typically outward-facing and / or arranged to contact the environment and / or positioned on the exterior of the gas-insulated electrical equipment. Outer surfaces may be at least partially annular, cylindrical, flat, and / or convex. The section is designed to retain or guide the insulating gas on one side and retain or guide the outer surface on the other side, making it possible for the section to leak or seep, in order to employ the method of the invention. Typically, the section includes at least one gap, path, orifice, and / or contact surface, particularly providing a possible path for leakage of the insulating gas. At least one gap, path, orifice, and / or contact surface may be arranged between two or more outer surfaces.

[0020] Surface treatment preferably includes mechanical and / or chemical processes to be applied to a surface (particularly the exterior). Surface treatment can essentially include subtractive manufacturing processes. Surface treatment can include heating, machining, grinding, brushing, dry ice blasting, laser cleaning, wiping, etc. For example, due to regulations near gas-insulated electrical equipment, sandblasting and / or abrasive and / or etching chemicals may be specifically avoided. In a simple manner, surface treatment can include, for example, cleaning the exterior with water, acetone, alcohol, or other chemicals and / or cleaning agents, and / or polishing the exterior, for example, using sandpaper or abrasive paper. Surface treatment can provide at least one or both of the following: increasing the surface roughness of the exterior (e.g., roughness values ​​Ra and / or Rz), and removing material from the exterior. Surface treatment can be configured to avoid cutting and / or sandblasting.

[0021] The adhesive preferably relates to at least a partially fluid, liquid, and / or viscous material. The adhesive preferably relates to a material with at least temporary tackiness, such as a resin or epoxy resin. The adhesive can be configured for molding and / or producing composite materials. The adhesive is generally configured as a non-reactive or reactive adhesive. The adhesive may include or consist of a polymer compound specifically configured to provide adhesion. The adhesive particularly includes at least one organic compound. The adhesive may include or consist of an elastomer, thermoplastic, emulsion, and / or thermosetting plastic. Examples of adhesives are: epoxy resins, polyurethanes, PMMA, cyanoacrylates, and acrylic polymers. In particular, the adhesive can be a two-component (2K) adhesive or a multi-component adhesive, such as comprising one or more polymer compounds and / or having an epoxy resin matrix. In particular, the adhesive can be a hardener mixed with one or more polymer compounds or a hardener configured to be mixed with one or more polymer compounds. Mixing can be performed during the treatment (e.g., application and / or injection) of the adhesive. The adhesive can be considered a molding material. The adhesive can be configured to be non-toxic with health, safety, and environmental (HSE) considerations.

[0022] Applying adhesive to the exterior can include applying the adhesive substantially to the entire exterior. The adhesive may be in direct contact with and / or directly attached to the exterior. The adhesive may be applied using an application tool, such as a roller, brush, applicator, sprayer, etc. The adhesive may be spread or distributed after application to achieve a substantially uniform thickness across the entire exterior. Application may include applying the adhesive substantially only to the exterior, or it may include applying the adhesive together with a flexible, flat material disposed on the exterior. Application is typically performed after surface preparation.

[0023] Arrangement may involve placing, rolling, and / or wrapping a flexible flat material on and / or around the outside, particularly on top of the adhesive. The flexible flat material may be arranged to contact and / or connect to the outside, particularly at least indirectly. The flexible flat material may be arranged to contact and / or connect to the adhesive, particularly directly. Arranging the flexible flat material may overlap with application in time, or may be performed after application is complete.

[0024] Flexible planar materials typically involve sheet materials, strip materials, tape materials, and / or pad materials. Flexible planar materials are typically, or can be, impregnated, covered, permeated, bonded, and / or coated with adhesives. In one embodiment, the flexible planar material is covered and / or permeated with an adhesive, especially prior to the placement step. The flexible planar material may include or consist of pre-impregnated fibers (i.e., prepreg) to be bonded and / or permeated with an adhesive. The prepreg may include fibers in a polymer matrix. The prepreg may be a polyester epoxy prepreg. Flexible planar materials, or any other materials listed herein, may include or consist of fibrous and / or woven materials, such as glass, carbon, aromatic polyurethanes, silicone resins, polymers (e.g., polyester), or basalt fibers, which are particularly to be bonded and / or permeated with an adhesive.

[0025] In particular, the flexible, flat material can be provided as a (raw material) that has been covered, coated, penetrated, and / or impregnated by an adhesive or another adhesive, especially making application and attachment essentially a single step. The other adhesive can be a corresponding adhesive or can be a different adhesive.

[0026] Composite materials (also known as composite materials or complexes) are generally understood to be materials comprising two or more constituent materials. These constituent materials have significantly different chemical and / or physical properties, wherein the constituent materials together can produce a material with properties different from those of the basic constituent materials. In composite materials, the individual constituent materials can remain substantially independent and distinct, thus distinguishing composite materials from mixtures and solid solutions.

[0027] Curing an adhesive can involve initiating a chemical reaction and / or waiting for the adhesive to harden and / or solidify. Curing can be performed by actively handling the adhesive and / or by allowing time to pass.

[0028] Gas-insulated electrical equipment may include at least one bolted connection structure, and particularly multiple bolted connection structures. One or more bolted connection structures may connect two parts of the gas-insulated electrical equipment, each of which forms part of a segment. Before or after application and / or arrangement, particularly before or after surface treatment, the method may include the steps of: at least partially removing one or more bolted connection structures, and installing replacement nuts to one or more bolted connection structures. Removing a portion of a bolted connection structure may involve removing and / or unscrewing the nuts of the bolted connection structure. The bolts of the bolted connection structure may be removed alternatively or additionally to remove the bolted connection structure. The bolts may be pushed out from one or more segments. When the bolted connection structure is at least partially removed, the accessibility of the segments' faces may be improved; for example, the axial faces and / or outer surfaces of the segments may be better accessible.

[0029] Removal may include unscrewing one or more nuts from one or more bolted connections. Installation may include screwing on one or more replacement nuts. The one or more replacement nuts may include a sealing ring, particularly each replacement nut including a sealing ring located specifically in a groove within the replacement nut. The replacement nut may be in the form of a cap nut, particularly including a sealing ring opposite, for example, a cap. The sealing ring may be configured to seal the section, particularly the bolted connection. Installation may include applying a torque of at least 50 Nm to one or more bolted connections, particularly 100 Nm ± 40 Nm. Prior to the installation step, grease, adhesive, etc., may be applied to one of the sealing rings of the replacement nut, for example, to increase surface contact and thereby enhance sealing performance. This solution provides improved sealing due to additional potential leakage in the section.

[0030] The segment may be a flange connection structure for gas-insulated electrical equipment. A flange connection structure may include at least one flange, particularly two mating flanges. A flange connection structure (particularly at least one flange or its mating flange and / or its other components (such as covers)) typically comprises or is composed of an aluminum alloy, which may be coated and / or sprayed, for example. A flange connection structure may include flanges enclosed by covers, plates, adapters, etc., and / or flanges connected to covers, plates, adapters, etc. A flange connection structure may include two, three, or more outer surfaces. A flange connection structure may include at least one axial face, for example, arranged substantially inclined or perpendicular to the outer surface and / or facing the axial direction. A flange connection structure may include two axial outer surfaces facing away from each other. A bolted connection structure may extend through at least one flange, particularly through a mating flange and / or through the flange and the cover / cover / etc. In particular, gaskets, annular gaskets, and / or O-rings may be arranged between mating flanges or between a flange and a cover / cover / etc. Specifically, spacers, for example in the form of annular spacers and / or spacers made of metal, may be arranged between mating flanges or between a flange and a cover / cover, etc. The spacers may have one or more outer surfaces. Specifically, the outer surfaces are arranged axially adjacent and / or substantially parallel to each other. The flange connection structure may have one or more contact surfaces, for example, where mating flanges and / or spacers and / or covers / covers, etc., contact each other. One or more contact surfaces may extend outwards toward the flange connection structure to be sealed, particularly by means of this method. One or more outer surfaces and / or one or more axial surfaces may substantially comprise annular shapes.

[0031] Application can be performed using a tool configured to distribute the adhesive substantially uniformly across the entire surface, particularly on the segment and / or across one or more outer surfaces. This tool can be a scraper, particularly a grooved scraper. Application can be performed using a grooved scraper to ensure uniform distribution of the adhesive across one or more outer surfaces. For example, in a first step, the adhesive can be applied to the segment, and in a subsequent step or another step performed concurrently with the first step, the adhesive can be distributed using a tool or scraper. Uniform distribution of the adhesive improves the seal by allowing the flexible, flat material to adhere better to the segment.

[0032] The tool or scraper may have a planar section, for example, made of a sheet material, and may include grooves, such as five or more grooves, on at least one lateral side. Between the grooves, the planar section may have substantially straight edges extending from the grooves, for example, where all the straight edges follow a substantially straight line. When distributing adhesive, the substantially straight edges may contact one or more outer portions while the grooved scraper moves obliquely relative to said edges. Thus, the grooves provide a cross-section through which the adhesive is pushed, allowing the adhesive to be evenly distributed.

[0033] Surface treatment may include removing an outer surface layer, which includes at least one of coatings, dirt, paint, and corrosive materials, particularly to expose the substrate of the segment, which may be metallic, particularly an aluminum alloy. The surface layer can be understood as the outermost material layer of the segment, particularly the outermost layer. The surface layer may include a thickness of at least 0.01 mm and / or at most 2 mm, particularly at most 1 mm or at most 0.5 mm, particularly an average thickness. Removal may be carried out by means of mechanical and / or chemical processes. Depending on the process performed, removal may inherently result in surface roughening. Removal improves the effectiveness of the seal.

[0034] Surface treatment can include machining the exterior using a rotating wire brush. A rotating wire brush can include radially outwardly extending steel wires configured as a tool to be rotated. The wires can be curved or straight. The rotating wire brush can be used with a drill, angle grinder, or other rotating tool. The rotating wire brush can produce cleaning and / or removal processes on the surface. Due to the high abrasion effect, the rotating wire brush can cause surface roughening, thereby improving the adhesion of adhesives.

[0035] The application and placement steps can be performed such that alternating and / or overlapping layers of adhesive and flexible planar material are provided, at least in the outer portion. For example, the flexible planar material can be stacked in some areas of the outer surface, or it can be stacked substantially along or around the entire outer surface. The application and placement can be repeated at least twice, preferably at least four times, and particularly at least five times. Alternating and / or overlapping layers improve mechanical stability and lifespan. The placement step may include pressing the flexible planar material against the adhesive and / or the outer surface to improve the bond between the adhesive and the flexible planar material and / or the outer surface. For pressing, a rotary tool or roller can be used.

[0036] It can be specified that the curing step be performed for at least a certain amount of time, such as 1 hour. Curing is performed particularly after the application and / or placement steps. Curing is performed primarily at room temperature, such as at 25°C ± 5°C and / or between 50°C and 0°C. Specifically, curing is performed for at least two hours or at least three hours. This curing time and temperature, especially in combination with two-component adhesives and / or reactive adhesives, has proven to produce good sealing results.

[0037] In a preferred embodiment, the flexible planar material comprises or is a molded prepreg, such as a pre-cured polyester epoxy prepreg. The flexible planar material can be provided as a strip having a length of at least 1 m or at least 2 m and / or long enough to wrap around the segment at least once or twice. Here, particularly throughout the application and arrangement process, the flexible planar material can be stacked in multiple layers, e.g., at least two, three, four, five, six, seven, or more layers. An arrangement can be performed to provide a first layer of flexible planar material, wherein a second layer of flexible planar material can be applied repeatedly before continuing the arrangement; this can be repeated further. This improves adhesion and sealing. Optionally, particularly throughout the application and arrangement process, the flexible planar material can be wound / rolled under tension for a tight fit.

[0038] Especially after application and / or placement, and particularly before curing, the following steps may be provided: wrapping a foil, which is a shrink foil, around the outside; and heating the foil, particularly with an external heater. The shrink foil may be configured to shrink upon heating. The shrinkage supports the bonding of the adhesive and the flexible flat material. The shrinkage may be permanent, especially after cooling. The foil may also be understood as a roll, film, or sheet, for example comprising or composed of a polymer compound. The external heater may be an electric heater, heating pad, blower heater, blower dryer, etc. In particular, when the flexible flat material is a molded prepreg and combined with the shrink foil, an excellent seal with a long service life can be provided. Here, the curing step may be performed for at least ten or twenty hours, particularly at room temperature. The shrink foil may be removed after curing.

[0039] In a preferred embodiment, the flexible planarizing material comprises or is a fibrous material, such as dry glass fiber, particularly in the form of a strip. The dry glass fiber can be provided without a matrix and / or without matrix impregnation. Here, particularly throughout the application and arrangement steps, the flexible planarizing material can be stacked in multiple layers, such as two, three, four, five, six, seven, or more layers. An arrangement can be performed to provide a first layer of flexible planarizing material, wherein a second layer of flexible planarizing material can be applied repeatedly before continuing the arrangement; this can be repeated further. Here, particularly throughout the application and arrangement, the flexible planarizing material can be wound / rolled under tension for a tight fit. Optionally, the stack of adhesive and flexible planarizing material can be wound with shrink foil, especially for a portion of the curing step.

[0040] Specifically, after curing (e.g., such that the adhesive and the flexible flat material (e.g., dry glass fiber tape) are at least partially bonded and / or form a composite material; preferably, the adhesive is at least substantially hardened and / or cured; in this case, curing may require one, two, three, or more hours; advantageously, the adhesive is not fully cured), the following steps can be provided: wrapping an impregnated mesh, particularly a net-bleeder, around the outside, specifically wherein the wrapping is performed at least twice to provide a stacked impregnated mesh layer; attaching a vacuum foil having at least one port to the outside; creating a vacuum inside the vacuum foil by applying suction to at least one port in a manner acting on the outside; injecting molding material and / or additional adhesive into at least one port for forming an additional composite material with the impregnated mesh. It should be noted that curing can be performed prior to the above steps, such that the adhesive is not fully hardened / cured; this results in the injected molding material being able to connect to the partially uncured adhesive, particularly its reactive molecules, and form a stronger bond. Flexible, flat materials, especially when used as dry glass fiber tapes, can be at least partially impregnated and / or soaked in molding materials, thereby improving mechanical stability and sealing effectiveness. For example, a curing time between two and four hours can be considered.

[0041] In particular, in conjunction with the above steps, the molding material may include a polymer compound, such as an epoxy resin, and optionally a hardener mixed with the polymer compound. Alternatively or additionally, the molding material may correspond to an adhesive, i.e., include at least one similar or equivalent component or may be the same. The molding material and / or adhesive may include or may be vulcanized rubber. The vacuum foil may have a vacuum port and a molding material inlet port as at least one port, preferably offset around the segment by 180° ± 90°. The vacuum foil may be sealed by means of a tape (e.g., adhesive tape). The molding material may cure for at least ten or twenty hours after injection, particularly at room temperature. The vacuum foil may be removed after curing. A vacuum may be generated using a vacuum pump or suction pump attached to at least one port. The molding material may be injected by attaching a container containing the molding material to at least one port and opening at least one port, particularly after a vacuum has been generated; thereby, the molding material is drawn into at least one port for distribution over the entire outer surface. An immersion net improves the flow of the molding material under vacuum to distribute substantially uniformly over the entire outer surface.

[0042] Particularly after the surface treatment step and especially before the application step, the method may include covering adjacent outer areas with a covering device (e.g., a tape) to prevent contamination of these areas, and in particular to prevent the application of adhesive to these areas. The covering device may be removed later, for example, after the application, placement, and / or curing steps.

[0043] Furthermore, this objective is specifically achieved by a kit specifically configured to perform a method / method, the kit comprising an adhesive, a flexible flat material, and a plurality of replacement nuts. The kit may also include a foil as a shrink foil. Alternatively or additionally, the kit may also include an impregnation mesh, a molding material, and a vacuum foil having at least one port. The features of the kit may be further defined by the features mentioned throughout this disclosure. The invention may also relate to the use of a kit, for example, for sealing sections of gas-insulated electrical equipment.

[0044] Furthermore, this objective is specifically achieved by a gas-insulated electrical device having sections, the gas-insulated electrical device comprising: Adhesive, which is applied to the outside of the segment, and A flexible planar material is disposed on the outside, and the flexible planar material forms a composite material with an adhesive. Optionally, the segment has a flange connection structure or a flange connection structure, which specifically includes two mating flanges or a flange closed by a cover. Specifically, the flange connection structure includes: two outer flanges and two axially opposite flanges, a bolted connection structure extending through the mating flanges or the flange and cover, and / or an annular gasket between the mating flanges or between the flange and the cover. Specifically, the outer flanges are arranged axially adjacent to each other. Optionally, the bolted connection structure includes a replacement nut with a sealing ring.

[0045] Gas-insulated electrical equipment is improved because leakage of the insulating gas is less likely to occur compared to known solutions.

[0046] Gas-insulated electrical equipment can be a result of the methods described herein and their preferred embodiments, and / or can correspond to the methods described herein and their preferred embodiments; therefore, for gas-insulated electrical equipment, corresponding features and / or descriptions can be adopted. Preferred embodiments of gas-insulated electrical equipment may be as follows.

[0047] Gas-insulated electrical equipment may include alternating layers and / or stacked layers of adhesive and flexible flat material disposed on the outside, as well as foil. The flexible flat material may include or may be a molded prepreg. The foil may be disposed on top of the flexible flat material.

[0048] Gas-insulated electrical equipment may include an impregnation mesh, and particularly a molding material forming an additional composite material with the impregnation mesh. Gas-insulated electrical equipment may include a vacuum foil disposed on the outside. The flexible flat material may include or be a fibrous material, such as dry glass fiber tape. The vacuum foil may be disposed on top of the impregnation mesh. The impregnation mesh may be disposed on top of the flexible flat material and / or the molding material.

[0049] Gas-insulated electrical equipment can be configured as gas-insulated switchgear or gas-insulated wiring with sections. Gas-insulated electrical equipment can be configured as medium-voltage or high-voltage equipment. Gas-insulated electrical equipment may include and / or be filled with an insulating gas, particularly under pressure. Sections may, for example, be in contact with the insulating gas on the side opposite to the outside and / or on the inner surface.

[0050] The term "high voltage" preferably refers to a voltage higher than 12kV, 36kV, 72kV, or 1100kV. High voltage preferably refers to a nominal voltage in the range of 12kV, 36kV, or 72kV up to 550kV or 1100kV, such as 145kV, 245kV, or 420kV, or even higher. The term "medium voltage" preferably refers to a voltage higher than 1kV, 12kV, or 36kV. Medium voltage preferably refers to a nominal voltage in the range of 1kV, 12kV, or 36kV up to 72kV, such as 5kV, 10kV, 25kV, or 70kV.

[0051] Gas-insulated switchgear may include grounding switches, circuit breakers, voltage converters and / or fast-acting grounding devices, for example including sections and / or mounted by means of sections, particularly including flange connection structures and / or mounted by means of flange connection structures.

[0052] Gas-insulated circuits may include nominal conductors supported within a housing of the gas-insulated circuit. The housing may extend substantially, for example, along an axial direction (particularly in the form of a tubular cross-section). The housing may include sections, particularly sections in the form of flanged connections. The housing is pressurized and filled with an insulating gas, or at least configured to be pressurized and filled with an insulating gas. The pressurized insulating gas generates forces that can act on the housing and thus on the sections (particularly the flanged connections).

[0053] The insulating gas and / or dielectric insulating medium can be any suitable gas capable of sufficiently extinguishing the arc formed between the contact elements during current-disconnecting operation, such as, but not limited to, inert gases, such as sulfur hexafluoride (SF6). Specifically, the insulating gas used can be SF6 gas or any other dielectric insulating medium and / or insulating gas, which can be gaseous and / or liquid, and particularly can be a dielectric insulating gas or an arc-extinguishing gas. Such dielectric insulating medium and / or insulating gas can, for example, encompass media including organofluorine compounds selected from the group consisting of fluoroethers, ethylene oxide, fluoroamines, fluoroketones, fluoroolefins, fluoronitriles, and mixtures thereof and / or their decomposition products. The insulating gas and / or dielectric insulating medium can be selected from the group consisting of hydrofluoroethers, perfluoroketones, hydrofluoroolefins, perfluoronitriles, and mixtures thereof.

[0054] Throughout this disclosure, the term "or" may be replaced by "and / or". Thus, the use of "or" does not necessarily mean that only (named) alternatives are listed. Attached Figure Description

[0055] These and other aspects of the invention will become apparent from the embodiments described below and will be elucidated with reference to the embodiments described below.

[0056] In the attached diagram: Figures 1A to 1BA flange connection structure as a prior art is shown in schematic diagram (A) and cross-section (B); Figure 2 One method is illustrated in the diagram; Figure 3 Another method is illustrated in the diagram; Figure 4 The diagram illustrates, for example, the method used for execution. Figure 2 A suite of methods; Figure 5 The diagram illustrates, for example, the method used for execution. Figure 3 Another suite of methods; Figure 6 A gas-insulating device is shown in cross-sectional view. This gas-insulating device can be used... Figure 4 kit Figure 2 The results of the method; and Figure 7 Another gas-insulating device is shown in cross-sectional view, which can be used with Figure 5 kit Figure 3 The result of the method. Detailed Implementation

[0057] Figure 1A and Figure 1B A section 110 of a gas-insulated electrical appliance 100 is shown. The gas-insulated electrical appliance 100 is a gas-insulated line (GIL) having a housing, conductors supported within the housing, and an insulating gas within the housing. Section 110 is a flange connection structure including two mating flanges 120. Furthermore, the appliance 100 has, as... Figure 1A The flange 120 shown on the right is closed by a cover or cap 121. Figure 1B It shows Figure 1A The cross-section of section 110.

[0058] The flange connection structure includes four outer surfaces 122 and axially opposite outer surfaces 124, a bolted connection structure 112 extending through the mating flange 120, and an annular gasket 114 in a groove 115 between the mating flanges 120. Two annular spacers 126 are arranged radially outward between the mating flanges 120 and the annular gasket 114. Each spacer 126 has one of the outer surfaces 122. The bolted connection structure 112 extends through the spacers 126. The four outer surfaces 122 are arranged axially adjacent. The four outer surfaces 122 are annular and / or cylindrical. It should be understood that the two outer surfaces 122 of the mating flange 120 are arranged to be at least indirectly axially adjacent. Contact surfaces 128 are positioned between each flange 120 and the axially directly adjacent spacer 126, and between two spacers 126, wherein corresponding components contact each other in terms of area. The contact surfaces 128 generally extend from the outer surfaces 122, particularly perpendicularly from the outer surfaces 122.

[0059] Typically, flange 120 and spacer 126 are made of metal, particularly aluminum alloy. The flange connection structure is typically coated or sprayed externally. Although the annular gasket 114 seals the flange connection structure to prevent outward leakage, especially when surrounded by grease, the present invention has found that over time, the annular gasket 114 may become leaky, allowing insulating gas to pass through the gap outwards. This may be due to the grease being washed away. The gap exists at the bolted connection structure 112 and / or at the contact surface 128 between one or more mating flanges 120 and / or one or more spacers 126. Essentially, a creep path 130 can be formed to allow insulating gas to exit the gas-insulated electrical equipment 100. Additionally, gas can leak through threaded hole 116, which is used to fill grooves with grease. As described herein, and particularly as described in the following paragraphs, the creep path 130 and / or threaded hole 116 can be sealed based on the present invention.

[0060] For example, a method has been proposed for sealing a segment 110 of a gas-insulated electrical device 100, such as a gas-insulated switchgear or a gas-insulated line. The method may include: surface-treating at least the outer surfaces of the segment 110 (e.g., one or more outer surfaces 122 and / or one or more axial outer surfaces 124); applying an adhesive 2 to the outer surfaces 122; distributing a flexible, planar material 4 on the outer surfaces 122; and curing the adhesive 2. This method can be advantageously applied to sealing components such as… Figures 1A to 1B The section 110 shown is sealed.

[0061] Figure 2A method for sealing a section 110 of a gas-insulated electrical device 100 is schematically illustrated. Section 110 is part of a flange connection structure similar to the flange connection structure of FIG1, which includes a bolted connection structure 112. This method may be referred to as a prepreg solution involving polyester epoxy prepreg.

[0062] Figure 2 The method includes the following steps, particularly in a given order or optionally in a different order, wherein steps may be optionally added, rearranged, changed, and / or omitted: Partially remove 20 of the bolted connection structure 112, including unscrewing the nut; Install the replacement nut 16 with a grease-lubricated sealing ring 18 onto the bolted connection structure 112 by applying a torque of 100 Nm ± 10 Nm; Surface treatment 30 is performed on at least the outer surface 122 of section 110 and / or surface treatment is performed on the outer surface 122, including cleaning the outer surface 122 and roughening the outer surface 122, including removing the surface layer of the outer surface 122 and processing the outer surface 122 by means of a rotating wire brush, wherein removal and / or installation 22 may also be performed after surface treatment 30. Use a grooved scraper to apply adhesive 2 40 to the outside 122; A flexible flat material 4 in the form of a molded prepreg is arranged on the outer surface 122. The molded prepreg is configured to be bonded and / or permeated by an adhesive 2 to form a composite material with the adhesive 2. The application 40 and arrangement 50 are repeated as shown by the dashed arrow, such that alternating layers and / or stacked layers of adhesive 2 and flexible flat material 4 are provided in at least a portion of the outer surface 122. Wrap 52 as a shrink foil 6 around the outside 122; The foil 6 is heated 54 using an external heater; and Allow adhesive 2 to cure at room temperature for at least 24 hours.

[0063] Figure 3 A method for sealing a section 110 of a gas-insulated electrical device 100 is schematically illustrated. Section 110 is part of a flange connection structure similar to the flange connection structure of FIG1, which includes a bolted connection structure 112. This method may be referred to as involving a vacuum immersion process.

[0064] Figure 3 The method includes the following steps, particularly in a given order or optionally in a different order, wherein steps may be optionally added, rearranged, changed, and / or omitted: Partially remove 20 of the bolted connection structure 112, including unscrewing the nut; Install the replacement nut 16 with a grease-lubricated sealing ring 18 onto the bolted connection structure 112 by applying a torque of 100 Nm ± 10 Nm; Surface treatment 30 is performed on at least the outer surface 122 of section 110 and / or surface treatment is performed on the outer surface 122, including cleaning the outer surface 122 and roughening the outer surface 122, including removing the surface layer of the outer surface 122 and processing the outer surface 122 by means of a rotating wire brush, wherein removal and / or installation 22 may also be performed after surface treatment 30. Use a grooved scraper to apply adhesive 2 40 to the outside 122; A flexible flat material 4 in the form of a fibrous material is arranged on the outer surface 122. The fibrous material is configured to be bonded and / or permeated by an adhesive 2 to form a composite material with the adhesive 2. As shown by the dashed arrow, the application 40 and arrangement 50 are repeatedly performed such that alternating layers and / or stacked layers of adhesive 2 and flexible flat material 4 are provided in at least a portion of the outer surface 122. Allow adhesive 2 to cure at room temperature for at least 3 hours (60°C). Wrap 62 around the outer 122 to immerse the mesh 8, wherein the wrapping 62 may be performed two or more times to provide a stack of immersion mesh 8; A vacuum foil 10 with two ports 12 is attached 64 to the outside 122; A vacuum 66 is generated inside the vacuum foil 10 by applying suction or vacuum to at least one port 12 in a manner acting on the outside 122; and Molding material 14 is injected 68 into at least one port 12 to form an additional composite material with the dip-in net 8, wherein molding material 14 corresponds to an adhesive, such as a polymer compound (e.g., epoxy resin), and a hardener mixed with the polymer compound.

[0065] Figure 4 It shows the configuration for execution Figure 2 Kit 1 of the method includes an adhesive 2, a flexible flat material 4, and multiple replacement nuts 16 with sealing rings 18. The kit also includes foil 6 as a shrink foil. The kit can provide substantially all the products required to perform the method, wherein some additional tools may be required or can be added to the kit, such as wire brushes, scrapers, heaters, compaction rollers, machine tools (wrenches, etc.), chemicals, cleaning agents, acetone, etc.

[0066] Figure 5 It shows the configuration for execution Figure 3Kit 1 of the method comprises an adhesive 2, a flexible flat material 4, and a plurality of replacement nuts 16 with sealing rings 18. The kit also includes an impregnation net 8, a molding material 14, and a vacuum foil 10 with at least one port 12. The molding material 14 may be the same as the adhesive 2, and thus can be understood as an additional adhesive. The kit can provide substantially all the products required to perform the method, wherein additional tools may be required or may be added to the kit, such as wire brushes, grooved scrapers, vacuum pumps, compaction rollers, machine tools (wrenches, etc.), chemicals, cleaning agents, acetone, etc.

[0067] Figure 6 and Figure 7 Each is shown as a gas-insulated electrical device 100 having a section 110 sealed using the method according to the invention. Section 110 is a flange connection structure comprising two mating flanges 120, each having an outer surface 122 and an axial outer surface 124. The axial outer surfaces 124 are axially opposite to each other. A bolted connection structure 112 extends through the mating flanges 120, and an annular gasket 114 is arranged between the mating flanges 120. Furthermore, a spacer 126 is arranged between the mating flanges 120, providing an outer surface 122. A contact surface 128 is positioned between the flanges 120 and the spacer 126. The gas-insulated electrical device 100 can be configured as a gas-insulated switchgear or a gas-insulated circuit having section 110.

[0068] Figure 6 The gas-insulated electrical equipment 100 includes an adhesive 2 applied to the outer surface 122 of a section 110, and a flexible flat material 4 in the form of a molded prepreg disposed on the outer surface 122, the flexible flat material forming a composite material with the adhesive 2. Essentially, the molded prepreg is bonded to the outer surface 122 by means of the adhesive 2. Optionally, the molded prepreg is permeated and / or impregnated by the adhesive 2. A foil 6, particularly a shrink foil, is disposed on top of the adhesive 2 and the flexible flat material 4. The gas-insulated electrical equipment 100 can be... Figure 2 The method is applied to the flange connection structure as a result. The outer surfaces 122 are arranged axially adjacent to each other. The bolted connection structure 112 includes a nut or replacement nut 16 with a sealing ring 18, which seals against possible leakage. The gas-insulated electrical equipment 100 includes alternating and / or stacked layers of adhesive 2 and flexible flat material 4.

[0069] Figure 7The gas-insulated electrical device 100 includes an adhesive 2 applied to the outer surface 122 of a section 110, and a flexible flat material 4 in the form of a fibrous material disposed on the outer surface 122, the flexible flat material forming a composite material with the adhesive 2. Essentially, the fibrous material is bonded to the outer surface 122 by means of the adhesive 2. Typically, the fibrous material is permeated and / or impregnated by the adhesive 2. The gas-insulated electrical device 100 also includes an impregnation mesh 8, a molding material 14 forming another composite material with the impregnation mesh 8, and a foil 10 disposed on the outer surface 122. The foil 10 is specifically disposed on top of the adhesive 2 and the flexible flat material 4, and specifically on top of the impregnation mesh 8 and the molding material 14. The foil 10 has at least one port 12 for vacuuming and / or injecting the molding material 14. The gas-insulated electrical device 100 can be... Figure 3 The method was applied to the results of flange connection structures.

[0070] List of reference numerals 2 Adhesives 4. Flexible flat materials 6 foils 8 Immersion net 10 Vacuum foil 12 ports 14. Molding materials 16 Replace the nut 18 Sealing ring 20 Remove 22 Installation 30 Surface Treatment 40 Apply 50 Arrangements 52 Entanglement 54 Heating 60°C Curing 62 Entanglement 64 Attachment 66 generated 68 injections 100 Gas-insulated electrical equipment Section 110 112 Bolted connection structure 114 Circular Washer 115 Groove 120 flange 121 Cover 122 Outside 124 Outside 126 spacers 128 contact surfaces 130 Path

Claims

1. A method for sealing a section (110) of a gas-insulated electrical device (100), the method comprising the steps of: At least the outer surface (122) of the segment (110) is subjected to a surface treatment (30), wherein the surface treatment (30) includes cleaning the outer surface (122) and / or roughening the outer surface (122). Apply adhesive (2) (40) to the outside (122). A flexible flat material (4) is arranged (50) on the outer surface (122), the flexible flat material (4) being configured to be bonded and / or permeated by the adhesive (2) to form a composite material with the adhesive (2), and The adhesive (2) is cured (60); wherein, The flexible flat material (4) includes molded prepreg or is a molded prepreg.

2. The method according to the preceding claim, wherein, The segment (110) includes a bolted connection structure (112). Before or after the application (40) and / or arrangement (50), particularly before or after the surface treatment (30), the method includes the following steps: At least partially remove (20) the bolted connection structure (112), and Install the replacement nut (16) (22) onto the bolted connection structure (112).

3. The method according to the preceding claim, wherein, Removal (20) includes unscrewing the nut of the bolted connection structure (112), and installation (22) includes screwing on the replacement nut (16) including the sealing ring (18), and Specifically, installation (22) includes applying a torque of at least 50 Nm, particularly 100 Nm ± 40 Nm, to the bolted connection structure (112), and Specifically, grease is applied to the sealing ring (18) of the replacement nut (16) before installation (22).

4. The method according to any one of the preceding two claims, wherein, The section (110) is a flange connection structure, which includes two mating flanges (120) or a flange (120) closed by a cover. The flange connection structure includes: The two outer surfaces (122) and two axially opposite outer surfaces (124), the bolted connection structure (112) extending through the mating flange (120) or the flange (120) and the cover, and the annular gasket (114) between the mating flanges (120) or between the flange (120) and the cover, wherein the outer surfaces (122) are arranged axially adjacent to each other.

5. The method according to any one of the preceding claims, wherein, The application (40) is performed using a grooved scraper to distribute the adhesive (2) evenly over the entire or one or more of the outer surfaces (120).

6. The method according to any one of the preceding claims, wherein, The surface treatment (30) includes: Remove the outer (122) surface layer, which includes at least one of a coating, dirt, and corrosive material; and / or The outer surface (122) is processed by means of a rotating wire brush.

7. The method according to any one of the preceding claims, wherein, Apply (40) and arrange (50) such that alternating layers and / or stacked layers of adhesive (2) and flexible flat material (4) are provided at least in the outer (122) portion. Specifically, the application (40) and arrangement (50) are repeated at least twice, preferably at least four times, and particularly at least five times.

8. The method according to any one of the preceding claims, wherein, Following the placement (50) step, the curing (60) step is performed substantially at room temperature and / or between 50°C and 0°C for at least one hour. Specifically, the curing (60) process takes at least 3 hours.

9. The method according to any one of claims 1 to 8, wherein after applying (50), the method comprises the following steps: A foil (6) is wound (52) on the outer surface (122), the foil (6) being a shrink foil, and The foil (6) is heated (54), specifically, the foil (6) is heated (54) by an external heater.

10. The method according to any one of claims 1 to 8, wherein after curing (60), the method comprises the following steps: An immersion mesh (8) is wound (62) onto the outer surface (122), specifically, wherein the winding (62) is performed at least twice to provide a stacked layer of the immersion mesh (8). A vacuum foil (10) having at least one port (12) is attached (64) to the outside (122). A vacuum (66) is generated inside the vacuum foil (10) by applying suction to the at least one port (12) in a manner acting on the outside (122). Molding material (14) is injected (68) into at least one port (12) to form an additional composite material with the dip-in mesh (8), particularly wherein, The flexible flat material (4) includes fibrous materials; and / or The molding material (14) corresponds to the adhesive and / or includes a polymer compound, such as an epoxy resin, and optionally includes a hardener mixed with the polymer compound.

11. A kit (1) configured to perform the method according to any one of the preceding claims, the kit (1) comprising an adhesive (2), a flexible flat material (4), and a plurality of replacement nuts (16), the kit further comprising: The foil (6) serves as a shrink foil, and / or The immersion mesh (8), molding material (14), and vacuum foil (10) having at least one port (12) are used, particularly wherein the molding material (14) corresponds to the adhesive (2), and / or wherein the adhesive (2) is a two-component adhesive.

12. A gas-insulated electrical device (100) having a section (110), comprising: Adhesive (2), said adhesive (2) is applied to the outside (122) of said segment (110), and A flexible flat material (4) is disposed on the outer surface (122), and the flexible flat material (4) forms a composite material with the adhesive (2). Optionally, the segment (110) is a flange connection structure, which includes two mating flanges (120) or a flange (120) closed by a cover. The flange connection structure includes: two outer flanges (122) and two axially opposed outer flanges (124), a bolted connection structure (112) extending through the mating flanges (120) or the flanges (120) and the cover, and an annular gasket (114) between the mating flanges (120) or between the flanges (120) and the cover, wherein the outer flanges (122) are arranged axially adjacent to each other. Optionally, the bolted connection structure (112) includes a replacement nut (16) with a sealing ring (18).

13. The gas-insulated electrical device (100) according to claim 12, comprising: Alternating and / or stacked layers of adhesive (2) and flexible flat material (4) and foil (6) disposed on the outside (122), wherein the flexible flat material (4) comprises or is a molded prepreg, and wherein the foil (6) is disposed on top of the flexible flat material (4).

14. The gas-insulated electrical device (100) according to claim 12, comprising: The immersion mesh (8), the molding material (14) forming another composite material with the immersion mesh (8), and the vacuum foil (10) disposed on the outside (122), wherein the flexible flat material (4) comprises or is a fibrous material, wherein the vacuum foil (10) is disposed on top of the immersion mesh (8), and the immersion mesh (8) is disposed on top of the flexible flat material (4), and in particular, wherein the molding material (14) corresponds to the adhesive (2).

15. The gas-insulated electrical device (100) according to any one of claims 12 to 14, wherein the gas-insulated electrical device (100) is configured as a gas-insulated switchgear or a gas-insulated circuit having the section (110).

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