Flange design for high voltage gas insulated switchgear (GIS), busbars and pipelines (GIL)

Abstract

The invention relates to a housing (1) for a gas-insulated medium-voltage or high-voltage device. The connection (4) between a first end (20) of a first housing tube (2) and a matching machined second end (30) of a second housing tube (3) has a gas discharge path (L) extending from the interior (6) to the exterior (7) of the housing tubes (2, 3). According to the invention, the gas discharge path (L1) is formed to have a first section (L1) extending along at least part of the axial direction of the housing (1) and provided with at least one sealing ring (5; 5a, 5b). In addition, an elongated annular snap-on bracket (9) can also be used. Direct machining of the matching housing ends (20, 30) allows the conventional flange to be omitted. The partial axial orientation of the gas discharge path (L) allows a plurality of sealing rings (5; 5a, 5b) to be provided continuously in the gas discharge path (L).

Description

Technical Field

[0001] The present disclosure relates to the field of high and medium voltage gas insulated switchgear (GIS), gas insulated busbars and gas insulated pipelines (GIL). A compact flange design contained in a gastight housing tube is disclosed, which provides a rigid but removable mechanical connection and gas seal for containing pressurized insulating gas therein. Furthermore, the present disclosure relates to a gas-insulated medium or high voltage device comprising such a flange, and a method for producing and assembling a housing for a gas-insulated medium or high voltage device comprising such a compact flange. Background Art

[0002] Gas-insulated switchgear and gas-insulated pipelines are made up of a few to several hundred components, including several interconnected busbars. Each component has its own housing, which is connected to the adjacent housing by flanges. The connection made by flanges must ensure mechanical stability, gas tightness and housing current. Therefore, the flanges are usually pressed against each other by applying high forces using several screws or bolt connections distributed around the circumference of the flange. The screw connection can be a screw-nut connection, or the screw can cooperate with the thread in the mating flange, or it can be a bolt with two nuts. The screws and bolts are set in corresponding holes on the flange. Sufficient channels must be provided for the bolts or screws that tighten the two sides of the flange. Since the housing acts as a pressure vessel, strict pressure vessel standards and tests also apply here, which vary for different countries.

[0003] The second method used to connect casings specifically for high voltage gas insulated pipelines is to weld them together. The casing ends are machined to allow for welds and welded in the field to form long busbars or lines.

[0004] Field welding of thin aluminum tubes requires a specific arc welding process to achieve a gas-tight and mechanically rigid connection in a construction site environment. Welded tubes cannot be disassembled in the event of a failure or maintenance. However, welded connections require less radial space than flanges, provide a lifetime seal, and reduce the parts required for assembly by avoiding separate flanges, bolts, washers, and nuts. The insulating gasket that holds the center conductor concentrically within the housing tube must be specially designed to fit in the welded housing because the welded connection does not have the typical gap used to secure the gasket between bolted flanges.

[0005] EP1058363A1, first published on December 6, 2000, with the applicant being Siemens AG, discloses a welded and releasable flange connection for a metal housing of a gas-insulated system. Two connecting flanges are welded at the ends of two different housing parts. The vertical planes of the flanges are then fixed together by a plurality of axial bolts or screws distributed along the circumference of the housing to provide a gas-tight connection.

[0006] Therefore, for assembly or disassembly of the housing, all bolts, nuts and washers must be tightened or loosened. The arrangement of the bolts in the flange holes allows for radial tolerances, which may result in insufficient concentricity between the housing and the conductor. Radial tolerances may also result in edges inside the housing, which is detrimental to the dielectric design.

[0007] EP2315326A1, first published on April 27, 2011, the applicant is ABB Technology AG, discloses a third method for connecting the housing of a high-voltage gas-insulated switchgear and a line by connecting the housing flange using a clamp design. The pressure of the compressed gas seal is achieved by using an angled slope on at least one side of the clamp, which forces the housing to move axially toward each other when the clamp is tightened. This requires fewer bolts and less assembly work than standard flanges. However, the radial space requirement around the clamp flange connection is as large as a conventional screw or bolt flange. Therefore, the clamp flange is not suitable for space-saving arrangement of three phases in power transmission or distribution systems.

[0008] DE 3347006 A1, first published on July 4, 1985, applicant Brown Boveri & Cie. AG, likewise discloses a medium-voltage gas-insulated switchgear with housings having flanges connected by clamping rings. The clamping ring has a U-shaped cross section for sealingly pressing the flat counter flanges together axially. The clamping ring can also press the sealing element radially against the outside of the flange, thereby extending the sealing path outside the flange.

[0009] In known designs, the flanges have flat surfaces oriented perpendicular to the housing axis and a seal is provided which is compressed axially between the flanges. Summary of the invention

[0010] Therefore, the object of the present invention is to provide an improved housing for a gas-insulated medium or high voltage device, which is very compact and easy to assemble and disassemble. Other aspects of the invention relate to a gas-insulated medium or high voltage device comprising such a housing, and a method for manufacturing and assembling such a housing.

[0011] These objects are achieved by the subject-matter of the independent claims. Some embodiments presented in the dependent claims and claim combinations provide further developments.

[0012] According to the present invention, the housing is for a gas-insulated medium-voltage or high-voltage device and comprises a first housing tube and a second housing tube, both having a longitudinal axis and a radial thickness and having a connection portion therebetween for providing a gas-tight connection between a first end of the first housing tube and a second end of the second housing tube, the connection portion providing a sealing element between the first end and the second end so that a gas exhaust path is sealed in a gas-tight manner, wherein the gas exhaust path is formed between the first end and the second end and starts from the inside of the first and second housing tubes and ends at the outside of the first and second housing tubes, the gas exhaust path having a first section extending along a direction having a directional component parallel to the longitudinal axis, and the sealing element is arranged in the first section.

[0013] This connection between the housing tubes has various advantages compared to known flange systems. No separate flange is required to provide a gas-tight connection between the housing tubes and the number of parts is greatly reduced. The flange design is integrated into the end of the housing tube. This makes it more compact than known flanges, especially in radial dimensions, and easier to manufacture and assemble the housing of the gas-insulated device. The flange design is also easy to open or remove.

[0014] Both ends of the housing tube may have the same first shape or finish (eg, both sides are concave), or the ends of the housing tube may have opposite shapes or finishes (ie, one side is convex and the other side is concave).

[0015] Very good results can be achieved by providing a gas exhaust path between the ends of the housing tube with a non-radial first path section or with an at least partially axial path section when viewed in a central length section including the central longitudinal axis z of the housing.

[0016] Very good results can be achieved by providing a shortest gas exhaust path, i.e. a gas exhaust path lacking any tangential component when having a non-radial first path section or having an at least partially axial path section from the inside to the outside of the housing tube between the ends of the housing tube.

[0017] Thus, such a design allows to extend the gas exhaust path between the ends of the housing tube, or to minimize the gas exhaust path in the radial direction (when viewed in a cross section of the central length of the housing), thereby improving the sealing without increasing the radial extent of the integrated flange design. In addition, the partial axial orientation of the gas exhaust path allows to arrange a plurality of sealing elements or sealing rings in succession along the gas exhaust path.

[0018] The following embodiments include modifications, improvements and / or variations of the protection member according to the present invention.

[0019] In an embodiment, a plurality of sealing elements or sealing rings may be arranged in series along the gas exhaust path. In an embodiment thereof, the inner sealing ring may be selected from materials and / or shapes suitable for the characteristics of the insulating gas compartment, such as the type of insulating gas, the gas pressure, the gas temperature, and the outer sealing ring may be selected from different materials suitable for the characteristics of the external environment, such as environmental conditions, including humidity, temperature, corrosive substances, etc. Additionally or alternatively, at least one of the sealing elements or sealing rings, such as the inner or middle sealing element or sealing ring, may be selected from materials and / or shapes to extend the diffusion time of small gas molecules, such as CO2, N2 or O2 gas molecules. Examples of materials may be EPDM (ethylene propylene diene monomer rubber), NBR (nitril butyl rubber), FEP (perfluorethylene propylene copolymer), PFA (polyfluoroalkoxy coploymer), PTFE (polytetrafluoroethylene) or others.

[0020] In an embodiment, the outer and / or middle sealing elements can be selected from EPDM or PTFE, which in particular offer a wide temperature range; and / or the middle and / or inner sealing elements can be selected from NBR, which in particular offer chemical resistance, for example for resistance to alternative synthetic insulating gases, such as fluorine- or chlorine-containing insulating gases, for example fluoroketones or fluoronitrile.

[0021] In an embodiment, one or more radial sealing rings may be provided. The radial sealing rings enhance the coaxial alignment of the first and second housing tubes and may compensate for final machining tolerances.

[0022] In an embodiment, the gas exhaust path has a second section whose extension direction has a directional component along the radius of the shell, and in particular the second section includes an inner second section starting from the inside of the shell and an outer second section ending outside the shell.

[0023] In an embodiment, the gas exhaust path may have a tortuous shape comprising at least two opposite bends, in particular an S-shape or a U-shape or a C-shape, when viewed in a cross section of the housing comprising the longitudinal axis.

[0024] In an embodiment, the gas exhaust path consists of a radially extending inner second section, a first section extending parallel to the longitudinal axis, and a radially extending outer second section.

[0025] In an embodiment, the connection portion provides a radial compression force on the sealing element for sealing the gas exhaust path.

[0026] In an embodiment, the connection portion provides an axial securing force for securing the first end and the second end together.

[0027] In an embodiment, the connection portion comprises a first embedded portion and a second embedded portion, the first embedded portion being joined to the first end, in particular by a welded connection, and the second embedded portion being joined to the second end, in particular by a welded connection. This allows the selection of a first and / or second housing tube having a reduced thickness d', for example 5 mm to 10 mm, more preferably 6 mm to 8 mm.

[0028] In an embodiment, the first end comprises a first connection surface, the second end comprises a matching second connection surface, and a gas exhaust path is formed between the first connection surface and the second connection surface, in particular the gas exhaust path is formed by the shortest path extending from the interior to the exterior of the housing tube.

[0029] In an embodiment, the first connecting surface and the second connecting surface have matching curved shapes with complementary bends, in particular the shape is selected from: a meandering shape with at least two opposite bends, such as an S-shape; a U-shape; a C-shape; and combinations thereof.

[0030] In another aspect of the housing, it comprises a first housing tube and a second housing tube, both having a longitudinal axis and a radial thickness, and a connection therebetween for providing a gas-tight connection between a first end of the first housing tube and a second end of the second housing tube, wherein a first connection surface, in particular a first protrusion and / or a first recess, is manufactured or machined into the first end, and a second connection surface, in particular a second protrusion and / or a second recess, is manufactured or machined into the second end.

[0031] The first and second ends may be machined on the inner diameter of the housing tubes so that the first housing tube may slide within the second housing tube, which forces them to be axially aligned.

[0032] In an embodiment, before manufacturing or processing the first and second connecting surfaces, the first end has the same inner diameter and outer diameter as the first housing tube; and / or the second end has the same inner diameter and outer diameter as the second housing tube; and / or the first end and the second end have the same inner diameter and outer diameter, respectively.

[0033] In an embodiment, the first and second housing tubes and the connection part, in particular the first and second connection surface, are made of metal, preferably aluminum, for example EN-AW 6082 or EN AW 6060 aluminum.

[0034] In an embodiment, an annular fixing bracket having a U-shaped cross section may be provided around the connection portion. The fixing bracket or simply the bracket may have an axial cutout to allow widening of the bracket for assembly. The bracket is widened to slide on one housing tube. After mating with the second housing tube to the final mating position, the bracket snaps or snaps into the rectangular slot or groove to fix them in place in this defined mating position.

[0035] In an embodiment, a securing rod may be secured across the axial cutout of the stent after the stent is snapped into the slot or groove. This improves proper assembly of the stent and keeps the stent in place. The securing rod may be secured by bolting, stamping, pins in holes, or any other locking mechanism. The securing rod is also useful as an assembly check because if the stent is not fully locked into the tube slot, it cannot be secured.

[0036] Other embodiments involve sealing the connection or flange after the bracket is installed. This can be achieved by sliding a heat shrink tubing over the assembled flange. This is possible because the outer diameter of the bracket is only slightly larger than the outer diameter of the tube. After shrinking, the heat shrink tubing can provide a seal against the external environment, and in particular can prevent water and dust from entering the flange. The heat shrink tubing also helps to secure the flange and the fixing rod in place.

[0037] In an embodiment, the spacer may be fixed in place inside the connection or flange. This may be achieved by a groove on the inner diameter of the interior of the housing, in particular the first housing tube. The spacer may be placed in the groove before the first housing tube is mated with the second housing tube. After mating the housing tubes, the spacer sinks into the groove and is fixed in place. Both faces of the groove may have radial edge fusion to smooth the electric field inside the housing.

[0038] In an embodiment, the housing may further comprise a length compensation element and / or a flexible angle unit, which may be arranged between the two housing tubes, in particular at one of the connections of the first housing tube and the second housing tube.

[0039] In an embodiment, a length compensation element may be arranged at one of the connecting parts of the first and second housing tubes, wherein a first section of the gas discharge path extends parallel to the longitudinal axis of the first and second housing tubes, and an axial expansion gap is provided at both ends of the first section to allow relative movement of a first end of the first housing tube and a second end of the second housing tube, in particular for compensating for thermal expansion or contraction or axial length tolerance of the first and / or second housing tube without affecting the gas-tight seal between the first end and the second end.

[0040] In an embodiment, the first and second housing tubes and / or the connection are made of a uniform material and / or are made without steel and / or without castings and / or without welds. This simplifies manufacturing. By using a uniform material, the surface roughness can also be more easily controlled or made uniform. This improves the dielectric properties inside the housing, in particular in the connection or in the region of insulating spacers or length compensation elements.

[0041] In an embodiment, the housing is designed to be pressurized with insulating gas at 3 to 12 bar, more preferably 6 to 10 bar.

[0042] In an embodiment, the housing is designed or used as a replacement or alternative for a medium voltage or high voltage cable.

[0043] In another aspect, a gas-insulated medium-voltage or high-voltage device is claimed, comprising a housing disclosed herein. For example, the gas-insulated device may be selected from: gas-insulated switchgear (GIS), such as disconnectors, circuit breakers, covers, bushings, cable terminals, connecting elements, busbars or others, and gas-insulated pipelines (GIL). In an embodiment, the gas-insulated medium-voltage or high-voltage device comprises or consists of a gas-insulated component, which uses a pressurized insulating gas selected from the group consisting of: air, N2, CO2, SF6, alternative synthetic insulating gases, and mixtures thereof.

[0044] In yet another aspect, a method for producing and assembling a housing of a gas-insulated medium-voltage or high-voltage device, in particular a housing as disclosed herein, comprises the following method elements:

[0045] a. in the first end (20) of the first housing tube, manufacturing, in particular processing, a first connecting surface,

[0046] b. In the second end of the second housing tube, manufacturing, in particular processing, a matching second connecting surface,

[0047] c. providing the first end with one or more sealing rings arranged at the first connection surface, and

[0048] d. Pushing the first and matching second connection surfaces into each other, thereby providing a gas-tight connection between the first and second housing tubes.

[0049] In an embodiment, the method comprises the following method elements:

[0050] e. providing an annular stent having a diameter and an axial width adapted to the first and second housing tubes, and having an axial slit,

[0051] f. elastically opening the stent radially at the axial slit, placing the stent on the connection portion, and elastically closing it radially again to provide an axial fixing force to fix the first and second housing tubes together, and / or provide sliding tolerance of the first end relative to the second end.

[0052] In an embodiment, the method comprises the following method elements:

[0053] g. making, in particular machining, grooves in the first and second housing tubes,

[0054] h. making, in particular machining, a bracket with an inward edge that matches the grooves in the first and second housing tubes, and

[0055] i. snapping the bracket into the grooves in the first and second housing tubes to provide an axial fixing force to fix the first and second housing tubes together and / or provide a sliding tolerance of the first end relative to the second end.

[0056] In an embodiment of the method, the first end, except for the first connection surface, has the same inner and outer diameters as the first housing tube, and the first connection surface is manufactured, in particular machined, to be thinner in diameter than the first housing tube.

[0057] In an embodiment of the method, the second end, except for the second connection surface, has the same inner diameter and outer diameter as the second housing tube, and the second connection surface is made, in particular machined, to be thinner in diameter than the second housing tube. In an embodiment, the first end and the second end may have the same inner diameter and outer diameter, respectively.

[0058] In the present application, the terms "radial", "axial", "center length section", "circumference" refer to the longitudinal axis z of the housing, or to the substantially cylindrical shape or symmetry of the housing.

[0059] It should be understood that both the foregoing general description and the following detailed description present embodiments with optional features and are intended to provide an overview or framework for understanding the nature and characteristics of the present disclosure. The accompanying drawings are intended to provide a further understanding and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate various embodiments and, together with the description, are used to explain, by example, the principles and operations of the disclosed concepts. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The invention described herein will be more fully understood from the detailed description given below and the accompanying drawings, which should not be considered as limiting the invention described in the appended claims. The drawings are as follows:

[0061] Figure 1 is a cross-sectional side view of a single-phase gas insulated line (GIL) according to the present invention;

[0062] Figure 2 yes Figure 1 Detailed illustration of a partial cross-sectional side view showing an embodiment of an integrated flange design;

[0063] Figure 3 is a perspective view of an embodiment of a bracket for enclosing and fixing a connecting portion;

[0064] Figure 4 is a perspective exterior view of a bus duct housing showing an embodiment of an integrated flange design in an assembled state;

[0065] Figure 5 is an embodiment of an integrated flange connection designed as an insert welded to the end of the housing tube; and

[0066] Figure 6 is an embodiment of an integrated flange connection designed as a length compensation element. DETAILED DESCRIPTION

[0067] Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying drawings, in which some, but not all, features are shown. The embodiments disclosed herein may be embodied in many different forms and should not be construed as limiting; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Wherever possible, like reference numerals will be used to refer to like components or parts.

[0068] Figure 1 A longitudinal section of a gas insulated line (GIL) is shown. The gastight housing, preferably made of metal, has a bus duct 1A or bus duct section 1A comprising a first housing tube 2 and a second housing tube 3 connected together at two connections 4 or flanges 4. The housing 1 houses a central conductor 12 suspended in an insulating gas compartment 13, thereby forming a single-phase encapsulated gas insulated line 1 or generally a gas-insulated device 1.

[0069] The bus duct housing tubes 2, 3 are firmly grounded and electrically connected to each other. The conductor 12 is connected to a high voltage source. The inner volume 13 of the bus duct 1A is filled with a high-pressure insulating gas, such as air, CO2, N2, SF6 or an insulating gas mixture. Typical insulating gas pressures are in the range of 3 bar to 10 bar.

[0070] In an embodiment, the disclosed integrated flange design can also be used to connect gas-insulated switchgear components other than gas-insulated pipelines, such as circuit breakers, disconnectors, busbars, earthing switches, compensator elements, angle connections, end caps, etc.

[0071] Combination Figure 2, the housing tubes 2, 3 have a connection portion 4 or an integrated flange 4 arranged therebetween. In the illustrated embodiment, the first connection surface 21 may include a first protrusion 22 located at the interior 6 of the housing 1 and a first recess 23 located at the exterior 7 of the housing 1, and the second connection surface 31 may include a second protrusion 32 located at the exterior 7 of the housing 1 matching the first recess 23 and a second recess 33 located at the interior 6 of the housing matching the first protrusion 22 to form a gas discharge path L. The first protrusion 22 may have at least one circumferentially extending sealing groove 50 on its outer surface 22o facing the second protrusion 32, for arranging at least one sealing ring 5a; 5b of the sealing element 5 therein. The first protrusion 22 may include two or more sealing grooves 50 arranged continuously along the gas discharge path L, for arranging two or more sealing rings 5a, 5b of the sealing element 5 therein.

[0072] like Figure 2 As shown, the gas discharge path L can be composed of a radially extending inner second segment L2i, a first segment L1 extending parallel to the longitudinal axis z, and a radially extending outer second segment L2o. More generally, when viewed in a cross-sectional area of ​​the housing including the longitudinal axis z, the first segment L1 should have at least a partial axial direction of the housing or a non-radial direction thereof.

[0073] The sealing element 5; 5a, 5b may include two or more sealing rings 5a, 5b, which are made of the same or different materials, such as EPDM, NBR, FEP, PFA, PTFE or other materials, and / or made of the same or different shapes, such as O-shape or X-shape.

[0074] In an embodiment, a sealing ring or O-ring 5b made of a material most suitable for the internal gas or its gaseous decomposition products may be used in the internal sealing groove 50. Another sealing ring or O-ring 5a of a different material may be used in the external sealing groove 50, which is most suitable for sealing the external gas (mainly air) and / or achieving the required temperature range.

[0075] In an embodiment, grease may be applied to the sealing element or O-ring to facilitate easier sliding during assembly and disassembly and to maintain its flexibility during a possible service life of several decades. Similarly, during assembly, contact grease may be used on the bracket grooves 2b; 3b, 3b' to maintain good electrical contact and low electrical contact resistance between the brackets 9, 9' and the first and second housing tubes 2, 3.

[0076] The first connection face 21, in particular the first protrusion 22 thereof, may have a spacing groove 80 on its inner surface 22i oriented toward the interior 6 of the housing 1, for receiving and fixing the outer part of the insulating spacer 8, in particular a disc-shaped supporting insulator 8 or a disc-shaped separating insulator 8 or two or three post-type insulators, for fixing the conductor 12 at the center inside the housing 1. The spacing groove 80 may be provided with a circular edge 20a, 30a, which is manufactured or machined into the first housing tube 2 and the second housing tube 3 with a specific radius, for relieving dielectric stress at three points between the housing 1, the insulating gas compartment 13 and the insulating spacer 8 and in the insulating spacer 8 of the gas-insulated medium-voltage or high-voltage device.

[0077] In an embodiment, the first connection surface 21, in particular the first protrusion 22 and / or the first recess 23, can be made or processed into the first end 20 of the first housing tube 2. The second connection surface 31, in particular the second protrusion 32 and / or the second recess 33, can be made or processed into the second end 30 of the second housing tube 3.

[0078] In an embodiment, the first end 20 and the second end 30, in particular the first connection surface 21 and the second connection surface 31, can slide into each other to join the first housing tube 2 with the second housing tube 3, in particular axially overlapped and gas-tightly joined. The slidability for joining also allows the integrated flange connection disclosed herein to be slidably removed. For example, the first connection surface 21 and the second connection surface 31 can have matching cylindrical or conical shapes to ensure that they can slide into or onto each other and provide axial overlap and gas-tight sealing.

[0079] therefore, Figure 2 It is shown that the first housing tube 2 is machined at the right end 20 to have a bracket groove 2b, O-ring grooves 5a, 5b and a spacing groove 80 on the interior 6. The mating surface or first connection surface 21 on the outer diameter provides a defined contact point for mating with the second end 3 or second connection surface 31 of the second housing tube 3. The other end of the first housing tube 2 (not shown) can have the same machining or machining of the second housing tube 3. In addition, a spacer 8 can be placed in the spacing groove 80 of the first housing tube 2. One or more O-rings 5a, 5b can be placed in the O-ring groove 50 for sealing the gas compartment 13.

[0080] The second housing tube 3 is machined with similar bracket grooves 3b; 3b', and additionally at the left end 30 or second connection surface 31 on the inner diameter, matches and slides on the O-ring surfaces 5a, 5b of the first housing tube 2. When engaged with the first housing tube 2, the second housing tube 3 is forced to axially align, and it radially presses the O-rings 5a, 5b into the O-ring grooves 50. The other end (not shown) of the second housing tube 3 can have the same machining or the machining of the first housing tube 2. The spacer 8 placed in the spacing groove 80 will be locked in place by the second housing tube 3.

[0081] Before processing, the two housing tubes 2, 3 can have the same outer diameter and inner diameter. Typical housing diameters of high-voltage switchgear are 150 mm to 600 mm. Advantageously, the housing tube thickness is selected in the range of 6 mm to 15 mm.

[0082] The bracket slot or groove 2b; 3b, 3b' can be a rectangular cross section (as shown) or a cross section of a different shape, which has at least a flat side portion facing the matching surface of the second connecting surface 31.

[0083] Figure 2 Combination Figure 3 as well as Figure 6 The connection 4 is shown to include a fixing bracket 9, 9' around the first end 20 and the second end 30. One purpose of the bracket 9, 9' is to provide an axial fixing force to better fix the first end 20 and the second end 30 together. The bracket 9, 9' may have a partial annular shape with an axial slit 9a, which allows the bracket 9, 9' to be resiliently snap-fit ​​onto the connection 4. The bracket 9, 9' may have an axial bracket width 9c (e.g., which may be defined between the first edge 90 and the second edge 91, 91'), which covers the connection 4 and matches the connection longitudinally, or alternatively, is longer than the connection 4 to improve the mutual axial alignment of the first and second housing tubes 2, 3, or to compensate for the thermal length extension of the housing 1. In an embodiment, the sliding width of the axial slit may be in the range of 0.2mm to 25mm, preferably in the range of 5mm to 15mm. This allows the insertion of a suitable tool for mounting and / or removing the bracket 9, 9' onto the connection 4.

[0084] like Figure 3 or Figure 6As shown, the bracket 9, 9' can have an inward, at least partially circumferential first edge 90 at one axial edge position, and an inward, at least partially circumferential second edge 91, 91' at another axial edge position, and the first housing tube 2 can have a first groove 2b for accommodating the first edge 90 at its outer surface 2a, and the second housing tube 3 can have a second groove 3b, 3b' for accommodating the second edge 91, 91' at its outer surface 3a, so that the bracket 9, 9' provides an axial fixing force for fixing the first end 20 and the second end 30 together. Exemplary choices of the material of the bracket 9, 9' can be: metal, such as aluminum, preferably aluminum type EN-AW 6082 or EN AW 6060, or copper, or other conductive materials. This allows the housing current to be effectively conducted from the first housing tube 2 to the second housing tube 3 through the bracket 9, 9'. In the embodiment, the first groove 2b and the second groove 3b, 3b' are rectangular typical circumferential grooves, and the first edge 90 and the second edge 91, 91' have matching rectangular cross-sections to fit into the first groove 2b and the second groove 3b, 3b' respectively.

[0085] The widening of the bracket 9, 9' should be limited to the elastic stage of the bracket 9, 9' so that it can maintain close contact with the first housing tube 2 and the second housing tube 3 when it is snapped into the groove 2b; 3b, 3b', thereby restoring its original shape. The bracket 9, 9' can have a flat surface on its edge 90; 91, 91' because it only keeps the first housing tube 2 and the second housing tube 3 matched. The radial seal (O-ring) 5; 5a, 5b is squeezed by matching the two housing tubes 2, 3. No axial seal is required, so no axial pressing force is required, which is different from using a conventional clamp flange.

[0086] The cross section of the U-shaped bracket 9, 9' provides the required strength to hold the two tubes 2, 3 together against the thrust from the internal pressure. Since the typical diameter of the high-voltage equipment housing is several hundred millimeters, even if a smaller thickness is selected, the cross section of the bracket 9, 9' becomes very large. Therefore, the tensile strength requirements for the bracket 9, 9' are quite low, and aluminum can be selected as the bracket material.

[0087] Aluminium is advantageous as a bracket material because it creates a low resistance and high current connection between the two housing tubes 2, 3. When the flanges according to the above aspects are assembled and the interior 6 of the housing 1 (i.e. within the insulating gas compartment 13) is pressurized, both tubes 2, 3 will exert opposing axial forces on the brackets 9, 9'. This creates a high contact force between the tube slot walls 2b; 3b, 3b' and the bracket edges 90; 91, 91'. This enables high housing currents to be carried by the brackets 9, 9'. The contact force is provided by the internal pressure in the insulating gas compartment 13.

[0088] therefore, Figure 3 or Figure 5 or Figure 6 The following is shown in exemplary manner with respect to the bracket 9, 9': the annular bracket 9, 9' has an (inverted) U-shaped cross section with bracket teeth or edges 90; 91, 91' on each side. In the meshed position, the bracket teeth or edges 90; 91, 91' match in size and distance with the bracket slots or grooves 2b; 3b, 3b' machined on the first and second housing tubes 2, 3, respectively. The bracket 9, 9' has an axial cutout or slit 9a, which allows it to be widened to a diameter greater than the outer diameter of the housing tubes 2, 3. The bracket 9, 9' is widened for assembly and slides on one of the housing tubes 2, 3. After matching the housing tubes 2, 3, the bracket 9, 9' can match the bracket slots or grooves 2b; 3b, 3b' and can be snapped into these bracket slots or grooves. Since the bracket 9, 9' has been elastically deformed to widen, it will restore its original diameter and shape when it abuts against the slots or grooves 2b; 3b, 3b'.

[0089] The brackets 9, 9' provide mechanical fixation of the housing tubes 2, 3, and electrical connection of the housing current between the housing tubes 2, 3. The walls 2b; 3b, 3b' of the bracket slots or grooves will be pressed against the bracket teeth or edges 90; 91, 91' by the increased internal gas pressure. The bracket cross section, in particular the axial width 9b and the radial thickness 9c, should be selected to provide sufficient tensile strength to resist the thrust from the internal pressure during the burst pressure test. The bracket cross section must also be sufficient to carry the maximum housing current. Both can be achieved with a radial thickness 9c in the range of 2mm to 7mm.

[0090] like Figure 3 As shown, a fixing rod 10 can be provided for bridging the axial slit 9a in the bracket 9, 9', thereby fixing the bracket 9, 9' on the connection part 4. In the embodiment or in the entire application, when the bracket 9, 9' is installed on the connection part 4, no sealing function is provided for the housing 1 or at the connection part 4 or between the ends 20, 30 of the first housing tube 2 and the second housing tube 3. In particular, the bracket 9, 9' does not constitute part of the gas exhaust path L or extend the gas exhaust path. The fixing rod 10 can realize an assembly check of the correct position of the bracket 9, 9' in the groove 2b, 3b.

[0091] The fixing rod 10 is an optional safety measure. It can be fixed to the outside of the bracket 9, 9' so as to pass through its axial cutout or slit 9a. The fixing rod 10 can be fixed to the bracket 9, 9' by bolts or pins or screws on either side of the axial cutout 9a. Preferably, the hole of the fixing rod 10 can only match the hole or thread of the bracket 9, 9' when the bracket 9, 9' is fully engaged in the bracket slot or groove 2b; 3b, 3b'. This provides a check for the correct assembly of the bracket. The fixing rod 10 can be labeled to indicate that it is dangerous to loosen it while the interior is still pressurized.

[0092] like Figure 4 As shown, the heat shrink tube 11 can be slid and fixed on the connection 4, in particular for applying additional radial compression force to the sealing elements 5; 5a, 5b to improve the sealing of the gas exhaust path L and / or inform the integrity of the connection 4. In an embodiment, the heat shrink tube 11 can be labeled on its outside to inform the manufacturer, inform the future maintenance date and / or warn of dangers, such as increased gas pressure in the housing 1, or when the housing 1 is pressurized, there is a risk of explosion when the bracket 9, 9' is removed.

[0093] Heat shrink tubing 11 is slid over flange assembly 4. When heated, tubing 11 shrinks to make close contact with housing tubes 2, 3 and brackets 9, 9' and fixing rods 10 (if present). This seals the connection or integrated flange 4 to prevent the ingress of water or dust or other harmful materials. Tube 11 shrunk around flange 4 supports brackets 9, 9' and fixing rods 10 (if present) to be fixed in place during operation of the housing. Heat shrink tubing 11 can be marked with company logos and other text to indicate that it is dangerous to remove it when the interior 6 is under pressure.

[0094] Regarding the internal design of the connection part 4, Figure 5 and Figure 2 Basically similar. Figure 5 As further shown, the connection portion 4 may comprise a first embedded portion 4a, which is joined to the first end 20 of the first housing tube 2, in particular via a welded connection 14, and a second embedded portion 4b, which is joined to the second end 30 of the second housing tube 3, in particular via a welded connection 14. This allows the selection of a first and / or second housing tube 2, 3 having a reduced thickness d', for example 5 mm to 10 mm, more preferably 6 mm to 8 mm.

[0095] In an embodiment, the housing may include a length compensation element 111 and / or a flexible angle unit (not shown in detail herein), which is arranged between two of the housing tubes 2 and 3, particularly at one of the connection portions 4 of the first housing tube 2 and the second housing tube 3.

[0096] Figure 6An example of such a length compensation element 111 is shown in FIG. The length compensation element 111 can be arranged at one of the connecting portions 4 of the first housing tube 2 and the second housing tube 3, wherein a first section L1 of the gas discharge path L extends parallel to the longitudinal axis z of the first housing tube 2 and the second housing tube 3, and an axial expansion gap 112 is provided at both ends of the first section L1 to allow a relative movement of the first end 20 of the first housing tube 2 and the second end 30 of the second housing tube 3, in particular to compensate for thermal expansion or contraction or axial length tolerance of the first housing tube 2 and / or the second housing tube 3 without affecting the gas-tight seal between the first end 20 and the second end 30. It can be used with Figure 2 The bracket 9 ′ is similar or equivalent to the bracket disclosed in , which additionally provides sliding tolerance of the first end 20 relative to the second end 30 .

[0097] Therefore, the length compensation element can have the same Figure 2 and Figure 5 The same or similar design as the integrated flange disclosed in . The relative movement between the first end 20 and the second end 30 is limited by the maximum and minimum axial expansion gaps 112 and ultimately by the sliding width of the bracket 9'. The length compensation element 111 allows the first connection surface 21 and the second connection surface 31 to be slidable into each other to compensate for the temperature elongation or contraction of the housing 1 or the busbar 1A or the gas-insulated device or the gas-insulated pipeline (GIL), in particular between the first end 20 fixed in a longitudinal fixed position 100f or 100g and the movable end 30 or the generally movable housing part 100m.

[0098] like Figure 6 Combination Figure 3 As shown, the anti-sliding bracket 9' can have an inward, at least partially circumferential first edge 90 at one axial edge position, and an inward, at least partially circumferential second edge 91' at another axial edge position, and the first housing tube 2 can have a first groove 2b for accommodating the first edge 90 at its outer surface 2a, and the second housing tube 3 can have a second groove 3b' for accommodating the second edge 91' at its outer surface 3a, wherein the second groove 3b' for accommodating the second edge 91' is extended by at least the length of the axial expansion gap 14, for example, compared with the previous groove 3b, and the second edge 91' provides a sliding tolerance on the outer surface 3a of the second housing tube 3, which is in addition to the axial fixing force provided by the bracket 9' for fixing the first end 20 and the second end 30 together.

[0099] Housings, gas-insulated medium or high voltage devices and methods for manufacturing and assembling housings or devices can be used for installation in radially confined spaces, such as pipelines, water pipes, tunnels, etc., and / or as an alternative or for avoiding or replacing electrical medium or high voltage cables.

[0100] Reference numerals

[0101] 1. Airtight shell, metal shell

[0102] 1A bus duct, bus duct section, medium voltage device, high voltage device

[0103] 2 First shell tube

[0104] 2a Outer surface of the first housing tube

[0105] 2b The first groove, rectangular groove in 2a

[0106] 20 First end of the first housing tube

[0107] 20a Rounded edge

[0108] 21 first connection surface of the first end

[0109] 22 A first protrusion on the first connecting surface inside the housing

[0110] 22i Inner surface of the first protrusion

[0111] 22o Outer surface of the first protrusion

[0112] 23 A first depression on the first connection surface outside the housing

[0113] 3 Second shell tube

[0114] 3a The outer surface of the second housing tube

[0115] 3b, 3b', the second groove and rectangular groove in 3a

[0116] 30 Second end of the second housing tube

[0117] 30a Rounded edge

[0118] 31 Second connection surface of the second end

[0119] 32 A second protrusion on the second connecting surface outside the housing

[0120] 33 A second recess on the second connection surface inside the housing

[0121] 4 Connection

[0122] 4a First embedding portion of the connecting portion

[0123] 4b Second embedding portion of the connecting portion

[0124] 5 Sealing elements, sealing rings

[0125] 5a First sealing ring, outer sealing ring, O-ring

[0126] 5b Second sealing ring, inner sealing ring, O-ring

[0127] 50 Sealing groove

[0128] 6. Inside the shell tube

[0129] 7 Outside of the housing tube

[0130] 8 Spacers, post-type insulators, disc-shaped insulators, support insulators, compartment insulators

[0131] 80 Spacing slots

[0132] 9 Bracket

[0133] 9' extended bracket, anti-slip bracket

[0134] 9a Axial slit in the stent

[0135] 9b Axial extension of the stent, stent width

[0136] 9c Thickness of the bracket (in radial direction)

[0137] 90 First edge of bracket

[0138] 91 Second edge of bracket

[0139] 91' Improved second edge, sliding edge of the bracket

[0140] 10 Fixing rod

[0141] 11 Heat shrink tubing

[0142] 12 Conductor

[0143] 13 Insulating gas compartment

[0144] 14Embedded connection, welding connection

[0145] 100f First vertical fixed position

[0146] 100g Second vertical fixed position

[0147] 100m Removable housing parts

[0148] 111 Length compensation element, length compensation unit

[0149] 112 axial expansion clearance

[0150] d Radial thickness of the shell tube or its end

[0151] d' radial thickness of the connecting part (insert) of the shell tube

[0152] d" Reduced radial thickness of the casing tube

[0153] L Gas exhaust path

[0154] L1 The first section of the gas discharge path with axial direction components

[0155] L2 The second section of the gas discharge path with radial components

[0156] L2i The second inner section of the gas discharge path from the inside of the shell tube 2, 3

[0157] L2o is the second section of the gas exhaust path that ends outside the shell tubes 2 and 3

[0158] x,y radial direction of the housing or medium or high pressure device

[0159] zThe longitudinal axis of the casing or the medium-pressure or high-pressure device.

Claims

1. A housing (1) for a gas-insulated medium or high voltage device, comprising a first housing tube (2) and a second housing tube (3), both having a longitudinal axis (z) and a radial thickness (d), and a connection (4) therebetween for providing a gas-tight connection between a first end (20) of the first housing tube (2) and a second end (30) of the second housing tube (3), The connection portion (4) provides a sealing element (5; 5a, 5b) between the first end (20) and the second end (30) so that the gas discharge path (L) is sealed in a gas-tight manner, wherein The gas exhaust path (L) is formed between the first end (20) and the second end (30), and starts from the inside (6) of the first and second housing tubes (2, 3) and ends at the outside (7) of the first and second housing tubes (2, 3), The gas exhaust path (L) has a first section (L1) extending along a direction having a directional component parallel to the longitudinal axis (z), and The sealing element (5; 5a, 5b) is arranged in the first section (L1); The connecting portion (4) comprises a bracket (9, 9') surrounding the first end (20) and the second end (30), and the bracket is configured to apply an axial fixing force to fix the first end (20) and the second end (30) together; The bracket (9, 9') has a partial annular shape with an axial slit (9a), which allows the bracket (9, 9') to be elastically snapped onto the connecting portion (4).

2. The housing (1) according to claim 1, wherein: The gas exhaust path (L) has a second section (L2) extending along the directional component of the radius (x, y) of the shell (1), the second section (L2) comprising an inner second section (L2i) starting from the interior (6) of the first and second shell tubes (2, 3) and an outer second section (L2o) terminating at the exterior (7) of the first and second shell tubes (2, 3); and wherein, when viewed in a cross section of the shell (1) including the longitudinal axis (z), the gas exhaust path (L) has a tortuous shape comprising at least two opposite bends, or the gas exhaust path (L) consists of the inner second section (L2i) extending radially, the first section (L1) extending parallel to the longitudinal axis (z), and the outer second section (L2o) extending radially.

3. The housing (1) according to claim 1, wherein: The connecting portion (4) provides a radial compression force on the sealing element (5; 5a, 5b) for sealing the gas exhaust path (L); and the connecting portion (4) provides an axial fixing force for fixing the first end (20) and the second end (30) together.

4. The housing (1) according to claim 1, wherein: The first end (20) includes a first connection surface (21), the second end (30) includes a matching second connection surface (31), and the gas exhaust path (L) is formed between the first connection surface (21) and the second connection surface (31).

5. The housing (1) according to claim 4, wherein: The first connecting surface (21) and the second connecting surface (31) have matching curved shapes with complementary bends, the shapes having a meandering shape with at least two opposing bends.

6. The housing (1) according to claim 4, wherein: The first connection surface (21) comprises a first protrusion (22) located at the inner part (6) of the housing (1) and a first recess (23) located at the outer part (7) of the housing, and the second connection surface (31) comprises a second protrusion (32) located at the outer part (7) and matching with the first recess (23) and a second recess (33) located at the inner part (6) of the housing (1) and matching with the first protrusion (22), so as to form the gas exhaust path (L); and The first protrusion (22) has at least one circumferentially extending sealing groove (50) on its outer surface (22o) oriented toward the second protrusion (32) for arranging at least one sealing ring (5a; 5b) of the sealing element (5) therein.

7. The housing (1) according to claim 6, wherein: The first protrusion (22) comprises two or more sealing grooves (50) arranged continuously along the gas discharge path (L) for arranging two or more sealing rings (5a, 5b) of the sealing element (5) therein.

8. The housing (1) according to claim 1, wherein: The sealing element (5; 5a, 5b) comprises two or more sealing rings (5a, 5b), which are made of the same or different materials and / or have the same or different shapes.

9. The housing (1) according to claim 8, wherein: The sealing ring is made of EPDM, NBR, FEP, PFA or PTFE.

10. The housing (1) according to claim 8, wherein: The sealing ring is formed in an O shape or an X shape.

11. The housing (1) according to claim 4, wherein: The first connection surface (21) has, on its inner surface (22i) oriented toward the interior (6) of the housing (1), an outer spacing groove (80) for accommodating and fixing an insulating spacer (8) for fixing a conductor (12) in the housing (1).

12. The housing (1) according to claim 11, wherein The insulating spacer (8) is a disc-shaped supporting insulating member or a disc-shaped separating insulating member or two or three column-type insulating members.

13. The housing (1) according to claim 6, wherein: The first protrusion (22) and the first recess (23) are manufactured or machined into the first end (20) of the first housing tube (2); the second protrusion (32) and the second recess (33) are manufactured or machined into the second end (30) of the second housing tube (3); and the first connecting surface (21) and the second connecting surface (31) are slidable into each other to join the first housing tube (2) with the second housing tube (3).

14. The housing (1) according to any one of claims 1 to 12, wherein: The bracket (9, 9') has an axial bracket width (9b) which covers the connection portion (4) and matches the connection portion longitudinally, or is longer than the connection portion (4) to improve the mutual axial alignment of the first and second housing tubes (2, 3) and compensate for the length thermal expansion of the housing (1).

15. The housing (1) according to any one of the preceding claims 1 to 12, wherein The support (9, 9') has an inward first edge (90) at one axial edge position and at least a partial circumference, and an inward second edge (91, 91') at another axial edge position and at least a partial circumference, and The first housing tube (2) has a first groove (2b) on its outer surface (2a) for accommodating the first edge (90), and the second housing tube (3) has a second groove (3b, 3b') on its outer surface (3a) for accommodating the second edge (91, 91'), so that the bracket (9, 9') provides an axial fixing force for fixing the first end (20) and the second end (30) together.

16. The housing (1) according to claim 15, wherein The first groove (2b) is a rectangular groove (2b) and the second groove (3b, 3b') is a rectangular groove (3b, 3b').

17. The housing (1) according to any one of the preceding claims 1 to 12, wherein: The bracket (9, 9') is made of metal so as to conduct the housing current from the first housing tube (2) to the second housing tube (3) through the bracket (9, 9').

18. Housing (1) according to the preceding claim 17, wherein The metal is aluminum or copper.

19. The housing (1) according to claim 18, wherein The aluminium is EN-AW 6082 or EN AW 6060 type aluminium.

20. The housing (1) according to any one of the preceding claims 1 to 12, wherein A fixing rod (10) is provided for bridging the axial slit (9a) in the bracket (9, 9') so as to fix the bracket (9, 9') on the connecting portion (4).

21. The housing (1) according to any one of the preceding claims 1 to 12, wherein: When the bracket (9, 9') is mounted on the connecting portion (4), it does not provide a sealing function for the housing (1) or the connecting portion (4), and does not constitute a part of the gas exhaust path (L) or extend the gas exhaust path.

22. The housing (1) according to any one of the preceding claims 1 to 12, wherein: The heat shrink tube (11) is slid and fixed on the connecting portion (4) to apply radial compression force on the sealing element (5; 5a, 5b) to improve the sealing of the gas exhaust path (L) and / or confirm the integrity of the connecting portion (4).

23. The housing (1) according to any of the preceding claims 1 to 12, comprising a flexible angle unit which is arranged between two housing tubes (2, 3) at one of the connections (4) of the first and second housing tubes (2, 3).

24. The housing (1) according to claim 15, comprising a length compensation element (111) arranged at one of the connecting parts (4) of the first and second housing tubes (2, 3), wherein The first section (L1) of the gas exhaust path (L) extends parallel to the longitudinal axis (z) of the first and second housing tubes (2, 3), and, An axial expansion gap (112) is provided at both ends of the first section (L1) to allow relative movement of the first end (20) of the first shell tube (2) and the second end (30) of the second shell tube (3), to compensate for thermal expansion or contraction or axial length tolerance of the first shell tube (2) and / or the second shell tube (3) without affecting the airtight seal between the first end (20) and the second end (30), and the bracket (9') provides a sliding tolerance of the first end (20) relative to the second end (30).

25. The housing (1) according to claim 24, wherein The second groove (3b') for accommodating the second edge (91') is extended by at least the length of the axial expansion gap (112), and the second edge (91') provides a sliding tolerance on the outer surface (3a) of the second housing tube (3).

26. The housing (1) according to any one of the preceding claims 1 to 12, wherein: The first and second housing tubes (2, 3) and the connecting part (4) are made of a unified material or without steel or castings or welds.

27. The housing (1) according to any one of the preceding claims 1 to 12, wherein: The housing (1) is designed or used as a replacement or substitute for a medium voltage or high voltage cable.

28. Gas insulated medium or high voltage installation comprising a housing (1) according to any of the preceding claims 1-27.

29. The gas-insulated medium-voltage or high-voltage device according to claim 28, wherein the device is selected from: a gas-insulated switchgear (GIS) and a gas-insulated line (GIL), wherein the gas-insulated switchgear (GIS) is a disconnector, a circuit breaker, a cover, a bushing, a cable terminal, a connecting element or a busbar.

30. The gas-insulated medium or high voltage device according to claim 28, comprising or consisting of gas-insulated components using a pressurized insulating gas selected from the group consisting of: air, N2, CO2, SF6, alternative synthetic insulating gases and mixtures thereof.

31. A method for producing and assembling a housing (1) according to any one of the preceding claims 1 to 27 for a gas-insulated medium-voltage or high-voltage device, comprising the following method steps: a. In the first end (20) of the first housing tube (2), making a first connecting surface (21), b. In the second end (30) of the second housing tube (3), a second matching connection surface (31) is produced, c. providing the first end (20) with one or more sealing rings (5; 5a, 5b) arranged at the first connection surface (21), d. pushing the first and matching second connection surfaces (21, 31) into each other, thereby providing a gas-tight connection (4) between the first and second housing tubes (2, 3); e. providing an annular support (9, 9'), the diameter and axial width of the annular support being adapted to the first and second housing tubes (2, 3), and the annular support having an axial slit (9a), and f. elastically opening the bracket (9, 9') radially at the axial slit (9a), placing the bracket (9, 9') on the connecting portion (4), and elastically closing it radially again to provide an axial fixing force to fix the first and second housing tubes (2, 3) together.

32. The method according to claim 31, comprising the following method steps: g. Making grooves (2b, 3b, 3b ') in the first and second housing tubes (2, 3), h. making the bracket (9, 9') with inward edges (90, 91, 91') that match the grooves (2b, 3b, 3b') in the first and second housing tubes (2, 3), and i. snapping the bracket (9, 9') into the grooves (2b, 3b, 3b') in the first and second housing tubes (2, 3) to provide the axial fixing force to fix the first and second housing tubes (2, 3) together.

33. The method of claim 32, wherein: Step i comprises: snapping the bracket (9, 9') into the grooves (2b, 3b, 3b') in the first and second housing tubes (2, 3) to provide a sliding tolerance of the first end (20) relative to the second end (30).

34. The method according to claim 31, wherein: The first end (20) except the first connecting surface (21) has the same inner diameter and outer diameter as the first shell tube (2), and the first connecting surface (21) is made thinner in diameter than the first shell tube (2); and the second end (30) except the second connecting surface (31) has the same inner diameter and outer diameter as the second shell tube (3), and the second connecting surface (31) is made thinner in diameter than the second shell tube (3).

35. A method according to any one of the preceding claims 31 to 34, wherein: The first end (20) not including the first connection surface (21) and the second end (30) not including the second connection surface (31) respectively have the same inner diameter and outer diameter.

Images