CN213394022U

CN213394022U - Flange assembly for gas insulation equipment and gas insulation equipment

Info

Publication number: CN213394022U
Application number: CN202021710182.9U
Authority: CN
Inventors: 陈天送; 刘清俊; 沈海鹭; 陈达进; 王军; 温华新
Original assignee: Sdee Hitachi High Voltage Switchgear Co ltd; ABB Grid Switzerland AG
Current assignee: Shandong Electric Hitachi High Voltage Switch Co Ltd; Hitachi Energy Ltd
Priority date: 2020-08-17
Filing date: 2020-08-17
Publication date: 2021-06-08
Anticipated expiration: 2030-08-17

Abstract

The utility model provides a flange subassembly and including the gas insulation equipment of this flange subassembly for gas insulation equipment. The flange subassembly includes: at least one of the first flange and the second flange is provided with a plurality of connecting through holes which are arranged at intervals along the circumferential direction, and the connecting end surface of the first flange and/or the second flange is provided with an annular groove which extends along the circumferential direction and is communicated with the connecting through holes so as to be filled with first sealing grease; and a plurality of coupling assemblies, each coupling assembly including a first coupling member and a sealing gasket and configured to couple the first and second flanges. The first coupling member is disposed through the sealing gasket and the corresponding coupling through-hole, the sealing gasket being disposed for sealing an annular gap between an inner surface of the coupling through-hole and an outer surface of the first coupling member. According to the utility model discloses a flange subassembly and gas insulated equipment have better sealed/waterproof nature and later maintenance convenience.

Description

Flange assembly for gas insulation equipment and gas insulation equipment

Technical Field

The present invention relates generally to the field of gas-insulated equipment technology, and more particularly to a flange assembly for gas-insulated equipment and gas-insulated equipment including the same.

Background

The gas-insulated equipment is equipment in which an insulating gas is filled in a housing to ensure electrical safety, such as gas-insulated switchgear (GIS), gas-insulated transmission line (GIL), and the like.

Taking a gas-insulated switchgear as an example, it usually comprises a grounded housing and components such as circuit breakers and disconnectors. The shell parts of the shell are hermetically connected through flanges to form a closed space which is filled with SF₆The insulating gas of (1). Components such as circuit breakers and disconnectors are installed in the enclosed space for safe operation.

The gas insulation apparatus is generally used in outdoor environments, and thus, a gap between flange coupling surfaces and a bolt coupling portion of a flange may be corroded by infiltration of liquid such as rainwater, so that sealability of the flange coupling is reduced, resulting in SF₆Gas leaks, and then leads to gas insulated equipment to have the potential safety hazard.

At present, the existing flange connection waterproof measure is to coat waterproof glass cement on the gap between the flange connection surfaces and the bolt connection position of the flange. On the one hand, however, the glass cement is not beneficial to the disassembly of the subsequent flange and the maintenance of equipment after being cured; on the other hand, the glass cement itself is not conductive, which reduces the conductivity at the flange joint.

Therefore, there is still a need to develop a waterproof structure of a flange for a gas insulated apparatus, which can ensure the conductivity and detachability of the flange while having a good waterproof property.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a solve the problem that exists among the above-mentioned prior art just, provide a novel gas insulation equipment that is used for the flange subassembly of gas insulation equipment and includes this flange subassembly.

According to a first aspect of the present invention, a flange assembly for a gas insulated apparatus is provided. The flange assembly comprises a first flange and a second flange, at least one of the first flange and the second flange is provided with a plurality of coupling through holes which extend in parallel to the axial direction and are arranged at intervals along the circumferential direction, and the coupling end surface of the first flange and/or the second flange is provided with an annular groove which extends along the circumferential direction and is communicated with the plurality of coupling through holes so as to be filled with first sealing grease; and a plurality of coupling assemblies, each coupling assembly comprising a first coupling member and a sealing gasket and configured to couple the first flange and the second flange; wherein the first coupling member is disposed through the sealing gasket and the respective coupling through-hole; the sealing gasket seals an annular gap between an inner surface of the coupling through-hole and an outer surface of the first coupling member.

For the flange assembly for gas insulation equipment according to the present invention, the first sealing grease can fill the annular groove of the first flange and/or the first flange and the plurality of coupling through holes communicated with the annular groove, so that it can prevent external rainwater and the like from entering the gap of the first coupling member coupling (such as bolt coupling, stud coupling) and the gap between the flange coupling end faces to cause corrosion and destroy the sealing property of the flange coupling; the sealing gasket can further prevent the first sealing grease in the annular groove from overflowing through the connecting through hole; furthermore, the use of the first sealing grease allows the flange assembly to be easily disassembled, facilitating subsequent maintenance of the gas-insulated apparatus.

In accordance with the above technical idea, the first aspect of the present invention may further include any one or more of the following alternatives.

In some alternatives, the sealing gasket comprises: the gasket comprises a gasket body with a through hole and a first sealing ring; the gasket body is provided with an annular concave part surrounding the through hole and used for accommodating the first sealing ring; the first seal ring is disposed to abut toward the coupling through-hole.

In some alternatives, the annular recess and the first seal ring are sized such that the first seal ring has a predetermined compressibility and packing rate.

Wherein, first sealing washer holding makes in the annular recess of gasket body and have suitable compression ratio and packing rate: the first sealing ring can be ensured to be capable of sealing the annular gap between the inner surface of the corresponding connecting through hole and the outer surface of the corresponding first connecting piece well, and the first sealing ring can be prevented from being excessively compressed and damaged prematurely.

In some alternatives, a second seal ring for sealing a gap between coupling end faces thereof is provided between the first and second flanges, the second seal ring being located radially inward of the first and/or second flanges with respect to the annular groove. The second seal ring can seal a gap located on the radial inner side between the connecting end face of the first flange and the connecting end face of the second flange, and prevent the leakage of insulating gas in the gas insulating equipment.

In some alternatives, a second sealing grease is provided on the coupling end face of the first flange and/or the second flange, the second sealing grease being applied to a region located radially outward of the first flange and/or the second flange relative to the second sealing ring, the second sealing grease being an electrically conductive sealing grease. The sealing grease is coated in the area, so that external rainwater and the like can be prevented from entering a gap between the flange joint end faces and positioned on the radial outer side to cause corrosion to damage the sealing performance of the flange joint, the first sealing grease in the annular groove can be prevented from overflowing from the gap between the flange joint end faces, and meanwhile, the conductive sealing grease has the advantage of keeping the conductivity between the first flange and the second flange.

In some alternatives, the second sealing grease is a conductive silicone grease.

In some alternatives, the first sealing grease is the same as the second sealing grease.

In some alternatives, the first flange is provided with a plurality of coupling through holes, the second flange is correspondingly provided with a plurality of coupling blind holes extending from a coupling end face of the second flange in parallel to the axial direction; or the first flange and the second flange are both provided with a plurality of connecting through holes.

In some alternatives, the first coupling is a bolt or a stud.

In some alternatives, the coupling assembly further includes a second coupling in the form of a nut.

In some alternatives, the first flange and the second flange are each connected to a different housing portion of the gas insulation apparatus.

According to a second aspect of the present invention, a gas-insulated apparatus is provided, comprising a flange assembly according to the first aspect of the present invention.

According to the utility model discloses a gas insulation equipment that is used for flange subassembly of gas insulation equipment and contains this flange subassembly has following advantage: the flange component has multiple sealing/waterproof designs, so that external rainwater and the like are effectively prevented from entering gaps of the flange component to cause corrosion, further, the leakage of insulating gas in the shell of the gas insulating equipment can be avoided, and the electrical safety of the gas insulating equipment is ensured; the sealing/waterproof effect is achieved through the sealing grease, so that the flange assembly can be easily disassembled, and the later maintenance of the gas insulation equipment is facilitated; the sealing grease which has the sealing/waterproof function at each position of the flange assembly can be effectively prevented from leaking/overflowing, and the subsequent maintenance time and cost are saved.

Drawings

Other features and advantages of the present invention will be better understood from the following detailed description of alternative embodiments, taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts, and in which:

fig. 1 shows a partial perspective view of a gas-insulated switchgear device according to an embodiment of the invention;

fig. 2 shows a partial cross-sectional view at a flange assembly of the gas-insulated switchgear device of fig. 1;

FIGS. 3a and 3b show perspective views of the gasket seal of the flange assembly of FIG. 2 from different perspectives;

FIGS. 4a and 4b show perspective views of the gasket body of the sealing gasket of FIGS. 3a and 3b from different perspectives;

FIG. 5 shows a perspective view of a first seal ring of the sealing gasket of FIGS. 3a and 3 b; and

fig. 6 shows a partial cross-sectional view at a flange assembly of a gas insulated switchgear according to another embodiment of the present invention.

Detailed Description

The practice and use of the embodiments are discussed in detail below. It should be understood, however, that the specific embodiments discussed are merely illustrative of specific ways to make and use the invention, and do not limit the scope of the invention. The description herein of the structural positions of the respective components, such as the directions of upper, lower, top, bottom, etc., is not absolute, but relative. When the respective components are arranged as shown in the drawings, these direction expressions are appropriate, but when the positions of the respective components in the drawings are changed, these direction expressions are changed accordingly.

In this context, the circumferential direction of the flange refers to a direction along the circumference of the flange, and the axial direction of the flange refers to a direction perpendicular to the circumferential direction of the flange. The coupling end face of a flange refers to the end face of the flange for abutment with another flange. "radially outer" and "radially inner" are relative concepts with respect to the annular member, with regions closer to the center of the ring of the annular member referred to as radially inner and regions further from the center of the ring referred to as radially outer, in contrast.

In this context, sealing grease refers to a non-setting type of sealant, which is usually a paste prepared by thickening a synthetic oil with an inorganic thickener and adding a solid filler, a functional additive, and/or a structure improver. The sealing grease can also have the characteristics of better electrical conductivity, thermal conductivity and the like through component adjustment. Sealing greases include, but are not limited to, fluorosilicones and silicone greases.

The concept of the present invention will be described below by taking a gas insulated switchgear and a flange assembly therein as an example. However, it will be appreciated that the flange assembly according to the present invention may be used in a wide variety of gas insulated apparatus including, but not limited to, gas insulated switchgear and gas insulated transmission lines.

Fig. 1 shows a receiving chamber 100 of a gas-insulated switchgear according to an embodiment of the present invention. Fig. 2 shows a partial cross-section of the receiving chamber 100 of fig. 1 at a flange assembly 102.

Referring to fig. 1 and 2, the housing that houses the chamber 100 includes several housing portions, such as a first housing portion 104 and a second housing portion 106. Wherein the first housing portion 104 and the second housing portion 106 of the receiving chamber 100 are sealingly coupled to each other by the flange assembly 102. The receiving chamber 100 may receive therein electrical components such as circuit breakers, disconnectors, and the like. The gas-insulated switchgear may comprise several housing chambers. The receiving cavities may have the same or different configurations. The receiving chambers and the housing portions thereof may be sealingly coupled together by a flange assembly having the same or similar structure as the flange assembly 102 to form a sealed space, which may be filled with, for example, SF₆To ensure safe operation of the electrical components therein.

The flange assembly 102 may include a first flange 108 and a second flange 110 and a plurality of coupling assemblies 112. First flange 108 and second flange 110 may be connected to first housing portion 104 and second housing portion 106, respectively, of receiving chamber 100. Each coupling assembly 112 is configured for coupling the first flange 108 and the second flange 110 to couple the first housing portion 104 and the second housing portion 106 of the receiving cavity 100 to each other.

According to the present invention, each coupling assembly includes a first coupling member (e.g., a bolt or a stud) and a sealing gasket, and the first coupling member is disposed to pass through the sealing gasket and coupling holes (e.g., including a coupling through-hole or a coupling blind-hole) on the first flange and the second flange. In some embodiments, the first and second flanges may each be provided with coupling through-holes, and accordingly, each coupling assembly comprises one first and one second coupling member and two respective sealing gaskets. In some embodiments, one of the first and second flanges may be provided with coupling through-holes and the other with blind coupling holes, respectively, each coupling assembly comprising a first coupling member and a sealing gasket. In some embodiments, a through coupling hole and a blind coupling hole can be formed on one flange at the same time to meet different practical requirements.

Specifically, in the embodiment shown in fig. 1 and 2, the first flange 108 and the second flange 110 are each annular and have substantially the same dimensions. The first flange 108 has a coupling end face 114 abutting the second flange 110 and a free end face 116 opposite to its coupling end face 114 in the axial direction of the first flange 108. Likewise, the second flange 110 has a coupling end face 118 abutting the first flange 108 and a free end face 120 opposite its coupling end face 118 in the axial direction of the second flange 110. The first flange 108 and the second flange 110 are respectively provided with a plurality of coupling through-

holes

122, 124 extending parallel to the axial direction and arranged at intervals in the circumferential direction. Also, the plurality of coupling through-holes 122 of the first flange 108 are aligned with the plurality of coupling through-holes 124 of the second flange 110, respectively, upon flange-mounting coupling.

In the embodiment shown in FIG. 2, each coupling assembly 112 includes a first coupling member 126, a second coupling member 128, and two sealing

gaskets

130a, 130 b. The first coupling member 126 is in the form of a bolt and the second coupling member 128 is in the form of a nut. Alternatively, the first coupling member may also be in the form of a stud.

Referring to fig. 2 to 5, the two sealing

gaskets

130a, 130b have the same structure. In some embodiments, sealing gasket 130a may include a gasket body 132a made of metal and a first seal 134a made of rubber. The gasket body 132a has a through hole 136a, and the gasket body 132a is provided with an annular recess 138a surrounding the through hole 136a for accommodating the first seal ring 134 a. Likewise, the sealing gasket 130b includes a gasket body 132b made of metal having a through hole and a first seal ring 134b made of rubber.

Each bolt 126 is disposed to sequentially pass through the sealing gasket 130a (specifically, the through hole 136a of the gasket body 132 a), the coupling through hole 122 of the first flange 108, the coupling through hole 124 of the second flange 110, and the sealing gasket 130b (specifically, the through hole of the gasket body 132 b) to be screw-coupled with the nut 128, thereby coupling the first and

second flanges

108 and 110 to each other.

In the embodiment shown in fig. 6, the flange assembly 202 may include a first flange 208 and a second flange 210, and a plurality of coupling assemblies 212. The first flange 208 is provided with a plurality of coupling through-holes 222 extending parallel to the axial direction and arranged at intervals in the circumferential direction. The second flange 210 is correspondingly provided with a plurality of coupling blind holes 223 extending from its coupling end face 218 in a direction parallel to the axial direction, which coupling blind holes 223 are internally threaded. Each coupling assembly 212 includes a first coupling member 226 in the form of a bolt and a sealing gasket 230. Each bolt 226 is disposed to be sequentially screw-coupled through the sealing gasket 230, the coupling through-hole 222 of the first flange 208, and the coupling blind-hole 223 of the second flange 210, thereby coupling the first and

second flanges

208 and 210 to each other.

According to the utility model discloses, in order to satisfy requirements such as gas insulated switchgear's waterproof, sealed and security, the flange subassembly has multiple sealed/waterproof design.

First, referring to fig. 2, a sealing/waterproofing design between the coupling end face 114 of the first flange 108 and the coupling end face 118 of the second flange 110 will be described.

The first flange 108 is provided with an annular opening 140 and an annular groove 142 extending in the circumferential direction on the coupling end face 114. Wherein the annular opening 140 is located radially inward of the first flange 108 relative to the annular groove 142. In other words, in the radial direction, the annular opening 140 is closer to the center of the first flange 108 than the annular groove 142.

A second sealing ring 141 made of rubber may be provided in the annular opening 140 of the first flange 108 for sealing a gap located radially inside between the coupling end face 114 of the first flange 108 and the coupling end face 118 of the second flange 110, preventing leakage of the insulating gas inside the accommodation chamber 100.

The annular groove 142 of the first flange 108 communicates with the plurality of coupling through-

holes

122, 124 on the first and

second flanges

108, 110 for filling with the first sealing grease.

Specifically, after the first flange 108 and the second flange 110 are coupled to each other by the plurality of coupling assemblies 112, a first sealing grease may be injected under pressure into the annular groove 142 through a glue injection nozzle on the first flange 108 in communication with the annular groove 142, and the first sealing grease may fill the annular groove 142 of the first flange 108 and the plurality of coupling through

holes

122 and 124 of the first flange 108 and the second flange 110 in communication with the annular groove 142 under pressure, so as to prevent external rain water and the like from entering a gap at a bolt coupling and a gap between flange coupling end faces to cause corrosion and destroy the sealing property of the flange coupling. Alternatively, the first sealing grease may be silicone grease. It is understood that an annular groove may also be provided on the coupling end face 118 of the second flange 110, or on both the coupling end face 114 of the first flange 108 and the coupling end face 118 of the second flange 110, in alignment with each other, as long as the annular groove is capable of communicating with the plurality of coupling through-

holes

122, 124 of the first and

second flanges

108, 110 for facilitating injection of the first sealing grease through the annular groove 142 to the plurality of coupling through-

holes

122, 124 of the first and

second flanges

108, 110.

In some embodiments, the coupling end faces 114, 118 of the first flange 108 and/or the second flange 110 are provided with a second sealing grease applied to a region radially outward of the first flange 108 and/or the second flange 110 relative to the second sealing ring 141. In other words, in the radial direction, the region of the coupling end faces 114, 118 of the first and/or

second flange

108, 110 that is further away from the center of the first and/or

second flange

108, 110 than the second sealing ring 141 is coated with a second sealing grease to further seal the radially outer gap between the coupling end faces 114, 118 of the first and

second flange

108, 110, such that: on one hand, external rainwater and the like are prevented from entering a gap between the flange connection end faces to cause corrosion and damage to the sealing property of the flange connection; on the other hand, the first sealing grease in the annular groove 142 of the first flange 108 is prevented from overflowing from the gap between the flange coupling end faces.

Further, since the second sealing ring 141 is relatively close to the inside of the receiving chamber 100, it may be affected by high temperature generated during operation of the gas insulated switchgear, and thus, it is possible to prevent the second sealing grease from adversely affecting the sealability of the second sealing ring 141 at high temperature by avoiding the application of the second sealing grease at the annular opening 140 of the first flange 108 receiving the second sealing ring 141 and at the region of the second flange 110 corresponding to the annular opening 140.

In a preferred embodiment, the second grease is a conductive grease to maintain electrical conductivity between the first flange 108 and the second flange 110. Alternatively, the second sealing grease may be a conductive silicone grease.

In some embodiments, the first sealing compound may be the same as the second sealing compound, which is also a conductive sealing compound. Alternatively, the first sealing grease may also be different from the second sealing grease.

In addition to the sealing/waterproofing design described above, the flange assembly 102 of the present invention also has additional sealing/waterproofing designs. Next, with reference to fig. 2 to 5, a sealing/waterproofing design of the bolt joint will be described.

At the bolt coupling, a sealing gasket 130a is interposed between the head 144 of the bolt 126 and the free end face 116 of the first flange 108 for sealing an annular gap between the inner surface of the coupling through hole 122 of the first flange 108 and the outer surface of the bolt 126. Similarly, a sealing gasket 130b is interposed between the free end surface 120 of the second flange 110 and the nut 128 for sealing an annular gap between the inner surface of the coupling through hole 124 of the second flange 110 and the outer surface of the bolt 126.

The sealing/waterproofing design of the bolted joint is described below using a sealing gasket 130a as an example. The first sealing ring 134a of the sealing gasket 130a is disposed to abut toward the coupling through hole 122 of the first flange 108. In certain embodiments, the annular recess 138a of the gasket body 132a and the first seal ring 134a are sized such that the first seal ring 134a has a predetermined compression rate and packing fraction. The compression rate of the first sealing ring 134a may be 15% to 30%. The filling rate of the first packing 134a refers to a filling ratio of the first packing 134a to the annular recess 138a of the gasket body 132a, and is less than 100%. As such, when the first and

second flanges

108 and 110 have been coupled to each other by the coupling assembly 112 and reach the predetermined preload, on the one hand, the first sealing ring 134a may be partially pressed into the annular gap between the outer surface of the bolt 126 and the inner surface of the coupling through-hole 122 of the first flange 108, and the inner side of the first sealing ring 134a may abut against the outer surface of the bolt 126, so that the first sealing ring 134a can better seal the annular gap between the outer surface of the bolt 126 and the inner surface of the coupling through-hole 122 of the first flange 108; on the other hand, the proper compression and packing rate of the first seal ring 134a may prevent premature failure of the first seal ring 134a by over-compression.

The sealing/waterproof design of the bolt joint can prevent external rainwater and the like from infiltrating into the bolt joint to cause corrosion to damage the sealing performance of the flange joint, and can also prevent the first sealing grease in the annular groove 142 of the first flange 108 from overflowing through the plurality of connecting through

holes

122 and 124 of the first flange 108 and the second flange 110.

The sealing/waterproofing design of the flange assembly 202 shown in fig. 6 is the same as the flange assembly 102 shown in fig. 2 and will only be briefly described herein. The second flange 210 is provided with an annular opening 240 extending in the circumferential direction on its coupling end face 218, the annular opening 240 being provided with a second sealing ring 241 therein. The first flange 208 is provided with an annular groove 242 extending in the circumferential direction on the coupling end face 214 for filling with a first sealing grease. The coupling end faces 214, 218 of the first flange 208 and/or the second flange 210 are provided with a second sealing grease which is applied to the region which is located radially outside the first flange 208 and/or the second flange 210 with respect to the second sealing ring 241. The sealing gasket 230 includes a gasket body 232 and a first sealing ring 234, and is sandwiched between the head 244 of the bolt 226 and the free end face 216 of the first flange 208. The first sealing ring 234 of the sealing gasket 230 abuts against the coupling through hole 222 of the first flange 208 for sealing an annular gap between the inner surface of the coupling through hole 222 of the first flange 208 and the outer surface of the bolt 226.

It should be understood that the embodiments shown in fig. 1-6 merely show the shape, size and arrangement of the various optional components of the gas insulation apparatus and flange assembly according to the present invention, however, they are merely illustrative and not limiting, and that other shapes, sizes and arrangements may be adopted without departing from the spirit and scope of the present invention.

The technical content and technical features of the present invention have been disclosed above, but it should be understood that various changes and modifications of the concept disclosed above can be made by those skilled in the art under the inventive concept of the present invention, and all fall within the scope of the present invention. The above description of embodiments is intended to be illustrative, and not restrictive, and the scope of the invention is defined by the appended claims.

Claims

1. A flange assembly for a gas insulation apparatus, characterized in that the flange assembly (102; 202) comprises:

a first flange (108; 208) and a second flange (110; 210), at least one of the first flange (108; 208) and the second flange (110; 210) being provided with a plurality of coupling through holes (122, 124; 222) extending parallel to the axial direction and arranged at intervals in the circumferential direction, an annular groove (142; 242) extending in the circumferential direction and communicating with the plurality of coupling through holes (122, 124; 222) being provided on a coupling end face (114, 118; 214, 218) of the first flange (108; 208) and/or the second flange (110; 210) for filling a first sealing grease; and

a plurality of coupling assemblies (112; 212), each coupling assembly (112; 212) including a first coupling member (126; 226) and a sealing gasket (130; 230) and being configured for coupling the first flange (108; 208) and the second flange (110; 210);

wherein the first coupling member (126; 226) is arranged through the sealing gasket (130a, 130 b; 230) and the respective coupling through hole (122, 124; 222); the sealing gasket (130a, 130 b; 230) seals an annular gap between an inner surface of the coupling through-hole (122, 124; 222) and an outer surface of the first coupling member (126; 226).

2. The flange assembly for a gas insulating device according to claim 1, characterized in that said sealing gasket (130a, 130 b; 230) comprises a gasket body (132a, 132 b; 232) having a through hole (136a) and a first sealing ring (134a, 134 b; 234); the gasket body (132a, 132 b; 232) is provided with an annular recess (138a) surrounding the through hole (136a) for accommodating the first sealing ring (134a, 134 b; 234); the first sealing ring (134a, 134 b; 234) is arranged to abut towards the coupling through hole (122, 124; 222).

3. The flange assembly for a gas insulating apparatus according to claim 2, characterized in that said annular recess (138a) and said first sealing ring (134a, 134 b; 234) are dimensioned such that said first sealing ring (134a, 134 b; 234) has a predetermined compression rate and filling rate.

4. A flange assembly for a gas insulation apparatus according to any one of claims 1 to 3, characterized in that a second sealing ring (141; 241) for sealing a gap between its coupling end faces (114, 118; 214, 218) is provided between the first flange (108; 208) and the second flange (110; 210), the second sealing ring (141; 241) being located radially inside the first flange (108; 208) and/or the second flange (110; 210) with respect to the annular groove (142; 242).

5. The flange assembly for a gas insulation apparatus according to claim 4, characterized in that the coupling end face (114, 118; 214, 218) of the first flange (108; 208) and/or the second flange (110; 210) is provided with a second sealing grease applied on a region located radially outside the first flange (108; 208) and/or the second flange (110; 210) with respect to the second sealing ring (141; 241), the second sealing grease being an electrically conductive sealing grease.

6. The flange assembly for a gas insulating apparatus according to claim 5, wherein said second sealing grease is a conductive silicone grease.

7. The flange assembly for a gas insulating apparatus according to claim 5, wherein said first sealing grease is the same as said second sealing grease.

8. The flange assembly for a gas insulation apparatus according to any one of claims 1 to 3, characterized in that the first flange (208) is provided with a plurality of coupling through-holes (222), the second flange (210) is correspondingly provided with a plurality of coupling blind holes (223) extending parallel to the axial direction from a coupling end face (218) of the second flange (210);

or the first flange (108) and the second flange (110) are each provided with a plurality of coupling through-holes (122, 124).

9. Flange assembly for a gas insulation apparatus according to claim 8, characterized in that the first coupling (126; 226) is a bolt or a stud.

10. The flange assembly for a gas insulation apparatus according to claim 9, characterized in that the coupling assembly (112) further comprises a second coupling member (128) in the form of a nut.

11. A flange assembly for a gas insulation apparatus according to any one of claims 1 to 3, characterized in that the first flange (108; 208) and the second flange (110; 210) are each connected to different housing parts (104, 106) of the gas insulation apparatus.

12. A gas insulation arrangement, characterized in that the gas insulation arrangement comprises a flange assembly (102; 202) for a gas insulation arrangement according to any one of claims 1-11.