Three-phase integrated insulation bushing and gas-insulated switchgear
By using a pre-embedded insert structure and sealing fit in the three-phase integrated insulating bushing, the problems of excessive insulating material and poor sealing effect are solved, achieving the effects of simplified installation and improved sealing performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XUCHANG XUJI DRIESCHER WEGBERG ELECTRIC
- Filing Date
- 2025-06-06
- Publication Date
- 2026-06-12
AI Technical Summary
Existing three-phase integrated insulating bushings use a lot of insulating materials, resulting in poor sealing performance and inconvenient installation, leading to deformation and leakage of the gas box, and the installation process is complicated.
The structure adopts a pre-embedded insert, with a central hole inside the insert that seals with the central conductor, reducing the use of insulation material, and improving connection stability and sealing effect through surface extension structure and sealing ring groove.
It reduces the use of insulation materials, improves sealing performance and ease of installation, avoids deformation of the gas box, and simplifies the installation process.
Smart Images
Figure CN224355051U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of power switchgear, and relates to a bushing, specifically a three-phase integrated insulating bushing and a gas-insulated switchgear. Background Technology
[0002] Double-box independent gas-insulated switchgear (C-GIS) is an important part of the medium-voltage switchgear field, widely used in power plant power consumption, power distribution in substations of transmission and transformation systems, and power distribution in industrial and mining enterprises. The wall bushing, as the core insulating component of the gas-insulated switchgear, serves to connect the two main busbars of the gas chambers while isolating the insulating gas between the two chambers. Therefore, insulation, sealing, and installation issues must be carefully considered when designing wall bushings. Currently, the widely used three-phase split-type wall bushing has a more complex installation process due to its split structure.
[0003] In the prior art, such as the utility model patent with authorization announcement number CN219393066U and authorization announcement date of 2023.07.21, a three-phase insulating bushing is disclosed. The three-phase insulating bushing includes a rectangular base and bushing components. The bushing components include a first bushing, a second bushing, and a third bushing arranged sequentially at intervals along the length of the base. The base and the bushing components are integrally cast. A conductive rod (i.e., a central conductor) is installed inside the three-phase bushing. The conductive rod is wrapped inside the bushing, and the diameters at both ends of the conductive rod are larger than the central diameter. The bushing components are integrally cast inside the bushing.
[0004] Although the use of a three-phase cast-in-one insulating bushing solves the problem of complex installation process of three-phase split through-wall bushings, the contact area between the conductive rod and the bushing needs to be increased to ensure the sealing effect between the conductive rod and the bushing. This will undoubtedly increase the amount of insulating material used in the bushing, thus increasing the cost. When the through-wall bushing is installed on the gas box, it will cause local weight increase, and the gas box will deform, reducing the sealing performance and making it easy to leak. Furthermore, the method of installing the conductive rod in the bushing by casting is inconvenient, as the conductive rod needs to be pre-embedded in the mold before the insulating material is cast. Utility Model Content
[0005] The purpose of this utility model is to provide a three-phase integrated insulating bushing to solve the problems of poor sealing effect and inconvenient installation caused by the use of excessive insulating materials in existing three-phase integrated insulating bushings. Another purpose of this utility model is to provide a gas-insulated switchgear to solve the problems of poor sealing effect and inconvenient installation caused by the use of excessive insulating materials in existing three-phase integrated insulating bushings.
[0006] To achieve the above objectives, the technical solution of the three-phase integrated insulating bushing provided by this utility model is as follows: it includes a casting base, in which a three-phase insert corresponding to the circuit is fixedly disposed, the insert being pre-embedded in the casting base during the casting of the base, a central hole being provided on the insert, a central conductor being fixedly inserted in the central hole, and the central conductor and the insert being sealed together by a sealing element.
[0007] Beneficial Effects: This utility model modifies the elements of the existing three-phase integrated insulating bushing by using an insert pre-embedded in the casting base during casting as the installation structure for the central conductor. This eliminates the need for a large amount of insulating material to ensure a seal within the bushing. Because a central hole is provided inside the insert, the central conductor can be fixedly inserted into it, and a sealing element between the two achieves a tight seal. This reduces the need for excessive insulating material, ensuring a proper seal between the central conductor and the insert. The reduced material usage also reduces the local weight of the gas box when the three-phase integrated insulating bushing is installed, preventing deformation. Furthermore, the installation process is simpler and more convenient compared to the existing integrated casting method.
[0008] Furthermore, a surface extension structure is provided on the outer surface of the insert.
[0009] Beneficial effects: The surface extension structure increases the surface area of the outer surface of the insert, which increases the contact area between the insert and the casting base during casting, thus ensuring a stable connection between the insert and the casting base.
[0010] Furthermore, the surface extension structure is a protrusion provided on the outer surface of the insert.
[0011] Beneficial effect: The raised structure facilitates actual processing.
[0012] Furthermore, the protrusions are arranged around the corresponding central conductor, and annular grooves are formed between adjacent protrusions.
[0013] Beneficial effects: This structure of protrusions and grooves maximizes the contact area between the insert and the casting base, further improving the stability of the connection between the two.
[0014] Furthermore, adjacent protrusions and annular grooves are smoothly connected.
[0015] Beneficial effect: The smooth transition between adjacent protrusions and annular grooves prevents stress concentration at the contact points between the insert and the casting base.
[0016] Furthermore, a sealing ring groove is provided on the wall of the central hole of the insert, and the insert and the corresponding central conductor are sealed together by the sealing ring in the sealing ring groove.
[0017] Beneficial effects: The sealing ring groove ensures that the sealing ring will not come out of the center hole due to friction when the center conductor is inserted into the center hole, thus ensuring the sealing effect and preventing the leakage of insulating gas.
[0018] Furthermore, both ends of the insert protrude from the corresponding side of the casting base.
[0019] Beneficial effects: The protruding ends of the insert increase the contact area between the insert and the center conductor, enabling the center conductor to be stably inserted into the insert.
[0020] Furthermore, a rounded corner structure is provided on the outer side of the end of the insert.
[0021] Beneficial effect: The rounded corner structure can prevent tip discharge from occurring at the ends of the insert.
[0022] Furthermore, the casting base is provided with a skirt on the outer periphery of each of the inserts to increase the creepage distance.
[0023] Beneficial effects: The umbrella skirt can increase the creepage distance, which helps prevent insulation breakdown caused by electric field concentration, improves the electrical strength of insulation, and increases the contact area with air, thus enhancing the heat dissipation effect.
[0024] To achieve the above objectives, the technical solution of the gas-insulated switchgear provided by this utility model is as follows: it includes a gas box and a three-phase integrated insulating bushing installed on the gas box. The three-phase integrated insulating bushing includes a casting base. An insert corresponding to the three phases of the circuit is fixedly installed in the casting base. The insert is pre-embedded in the casting base during the casting process. A central hole is provided on the insert. A central conductor is fixedly installed in the central hole. The central conductor and the insert are sealed together by a sealing element.
[0025] Beneficial Effects: This utility model modifies the elements of existing gas-insulated switchgear by using an insert pre-embedded in the casting base of the three-phase integrated insulating bushing as the mounting structure for the center conductor. This eliminates the need for a large amount of insulating material to ensure a seal within the bushing. Because a central hole is provided inside the insert, the center conductor can be fixedly inserted into it, and a sealing element between the two achieves a tight seal. This reduces the need for excessive insulating material, ensuring a proper seal between the center conductor and the insert. The reduced material usage also reduces the local weight of the gas box when installing the three-phase integrated insulating bushing, preventing deformation. Furthermore, the installation process is simpler and more convenient than the existing integrated casting method.
[0026] Furthermore, a surface extension structure is provided on the outer surface of the insert.
[0027] Beneficial effects: The surface extension structure increases the surface area of the outer surface of the insert, which increases the contact area between the insert and the casting base during casting, thus ensuring a stable connection between the insert and the casting base.
[0028] Furthermore, the surface extension structure is a protrusion provided on the outer surface of the insert.
[0029] Beneficial effect: The raised structure facilitates actual processing.
[0030] Furthermore, the protrusions are arranged around the corresponding central conductor, and annular grooves are formed between adjacent protrusions.
[0031] Beneficial effects: This structure of protrusions and grooves maximizes the contact area between the insert and the casting base, further improving the stability of the connection between the two.
[0032] Furthermore, adjacent protrusions and annular grooves are smoothly connected.
[0033] Beneficial effect: The smooth transition between adjacent protrusions and annular grooves prevents stress concentration at the contact points between the insert and the casting base.
[0034] Furthermore, a sealing ring groove is provided on the wall of the central hole of the insert, and the insert and the corresponding central conductor are sealed together by the sealing ring in the sealing ring groove.
[0035] Beneficial effects: The sealing ring groove ensures that the sealing ring will not come out of the center hole due to friction when the center conductor is inserted into the center hole, thus ensuring the sealing effect and preventing the leakage of insulating gas.
[0036] Furthermore, both ends of the insert protrude from the corresponding side of the casting base.
[0037] Beneficial effects: The protruding ends of the insert increase the contact area between the insert and the center conductor, enabling the center conductor to be stably inserted into the insert.
[0038] Furthermore, a rounded corner structure is provided on the outer side of the end of the insert.
[0039] Beneficial effect: The rounded corner structure can prevent tip discharge from occurring at the ends of the insert.
[0040] Furthermore, the casting base is provided with a skirt on the outer periphery of each of the inserts to increase the creepage distance.
[0041] Beneficial effects: The umbrella skirt can increase the creepage distance, which helps prevent insulation breakdown caused by electric field concentration, improves the electrical strength of insulation, and increases the contact area with air, thus enhancing the heat dissipation effect. Attached Figure Description
[0042] Figure 1 This is a cross-sectional view of the three-phase integrated insulating bushing provided by this utility model;
[0043] Figure 2 This is a top view of the three-phase integrated insulating bushing provided by this utility model;
[0044] Figure 3 This is a sectional view of the insert;
[0045] Figure 4 A top view of another embodiment of the three-phase integrated insulating bushing provided by this utility model;
[0046] In the diagram: 1. Casting base; 2. Center conductor; 3. Metal mounting base; 4. Shielding structure; 5. Insert; 6. Umbrella skirt; 7. Sealing ring groove; 8. Sealing groove; 9. Protrusion; 10. Center hole. Detailed Implementation
[0047] The features and performance of this utility model will be further described in detail below with reference to the embodiments.
[0048] In existing three-phase insulating bushings, the conductive rod is integrally cast inside the bushing. To ensure a good seal, the bushing encloses the conductive rod. While this provides a good seal, it increases the contact area between the bushing and the conductive rod, requiring a large amount of insulating material. When installed on a gas box, the weight of the bushing can cause localized deformation of the gas box, leading to a loose connection between the gas box and the insulating bushing, making it prone to leakage and ultimately reducing the sealing performance. Furthermore, because the conductive rod is cast inside the bushing, the manufacturing process is relatively complex.
[0049] To address this issue, this utility model provides a three-phase integrated insulating bushing and gas-insulated switchgear. It utilizes an insert to connect the casting base and the central conductor. The sealing element inside the insert is in a sealing fit with the central conductor, eliminating the need for a large amount of insulating material and ensuring the sealing performance between the two. Furthermore, the insert allows the central conductor to be fixedly installed inside, making installation more convenient. This solves the problems of poor sealing effect and inconvenient installation in the prior art due to the use of a lot of insulating material.
[0050] The overall design concept of the three-phase integrated insulating bushing provided by this utility model is as follows:
[0051] like Figure 1-3 As shown, the three-phase integrated insulating bushing of this utility model includes a casting base 1, which is used to connect with the gas box of the gas-insulated switchgear. Inserts 5 corresponding to the three phases of the circuit are fixedly installed in the casting base 1. The inserts 5 are evenly spaced on the casting base 1 and are pre-embedded in the casting base 1 during its molding process, thus connecting the inserts 5 to the casting base 1. A central hole 10 is provided on the insert 5, and a central conductor 2 is fixedly inserted into the central hole 10, thus connecting the central conductor 2 to the insert 5. This insertion method makes installation easier for workers. The central conductor 2 and the insert 5 are sealed together by a sealing element. The sealing element ensures the sealing performance between the insert 5 and the central conductor 2, preventing leakage of insulating gas. This solves the problems of poor sealing effect and inconvenient installation in the prior art due to the use of excessive insulating materials.
[0052] Based on the above overall description of the three-phase integrated insulating bushing of this utility model, a more specific embodiment is provided below:
[0053] like Figure 1-3As shown, a surface extension structure is provided on the outer surface of the insert 5. This surface extension structure increases the contact area between the insert 5 and the casting base 1. Since the insert 5 is pre-embedded in the casting base 1 during molding, a larger contact area makes the connection between the two more stable. Specifically, the surface extension structure consists of protrusions 9 on the outer surface of the insert 5. These protrusions 9 surround the corresponding central conductor 2, and adjacent protrusions 9 form annular grooves. The structure of the annular grooves and protrusions 9 constitutes a wave-shaped structure on the outer surface of the insert 5. The cooperation between the protrusions 9 and the annular grooves maximizes the contact area between the insert 5 and the casting base 1, further improving the stability of the connection between them. Adjacent protrusions 9 and annular grooves are smoothly connected to avoid stress concentration at the contact points between the insert 5 and the casting base 1. It should be noted that although... Figure 1 In the embodiment shown, the insert 5 has a surface extension structure that combines a protrusion 9 with an annular groove. However, in some embodiments, it can also be regarded as any structure that can increase the surface area of the insert 5, such as irregular protrusions, grooves, etc., which will not be listed here.
[0054] like Figure 3 As shown, a sealing ring groove 7 is provided on the wall of the central hole 10 of the insert 5. A sealing ring is installed in the sealing ring groove 7 so that the insert 5 and the corresponding central conductor 2 are sealed together by the sealing ring. The sealing ring groove 7 ensures that the sealing ring will not come out of the central hole 10 due to friction when the central conductor 2 is inserted into the central hole 10, thus determining the installation position of the sealing ring and ensuring the sealing effect, preventing the leakage of insulating gas. Of course, in other embodiments, the sealing ring groove 7 may not be provided on the insert 5, but may be provided on the central conductor 2. When the sealing structure uses filler, a filler cavity may also be provided in the inner hole of the insert.
[0055] Two sealing ring grooves 7 are provided, spaced apart along the extension direction of the central conductor 2, and two corresponding sealing rings are provided, which can improve the sealing performance between the insert 5 and the central conductor 2. In other embodiments, multiple sealing ring grooves 7 may be provided, with the number of sealing rings corresponding to the number of sealing ring grooves 7.
[0056] like Figure 1 As shown, both ends of the insert 5 protrude from the corresponding sides of the casting base 1, increasing the contact area between the insert 5 and the center conductor 2, allowing the center conductor 2 to be stably inserted into the insert 5. The protruding height of both ends of the insert 5 exceeds the casting base by at least 3mm. The outer edges of the protruding ends of the insert 5 are provided with rounded corner structures to prevent tip discharge and safety accidents. The radius of the rounded corners is not less than 5mm. In other embodiments, a wavy structure can also be provided at the ends of the insert 5 to prevent sharp corners.
[0057] like Figure 1-2 As shown, each insert 5 on the casting base 1 is provided with a skirt 6 to increase the creepage distance. The skirt 6 increases the creepage distance, helps prevent insulation breakdown caused by electric field concentration, improves the electrical strength of the insulation, and increases the contact area with air, enhancing heat dissipation. The skirt 6 is integrally cast. The skirt 6 consists of two umbrella-shaped structures, with a spacing of 10-30mm between adjacent umbrella-shaped structures, a height of 20-50mm, and a slope of 45°-80°. In other embodiments, the skirt 6 may consist of one umbrella-shaped structure or multiple umbrella-shaped structures. Figure 4 As shown, the structure of the umbrella skirt 6 can also be linear (circular).
[0058] A shielding structure 4 is integrally cast inside the umbrella skirt 6 on the outer side of the central conductor 2, and is arranged along the axial direction of the central conductor 2. The shielding structure 4 can improve the insulation performance of the insulating sleeve and prevent safety accidents. The shielding structure 4 is a cylindrical metal structure with rounded corners at the ends having a radius of not less than 5 mm, and is symmetrically arranged in the umbrella skirt 6, communicating with the ground electrode. In other embodiments, a shielding structure 4 can be provided in each umbrella skirt 6.
[0059] Metal mounting seats 3 are provided at both ends of the casting base 1. The metal mounting seats 3 are pre-embedded within the casting base 1 during its molding process and are used to connect to the gas box of the gas-insulated switchgear. A sealing structure and a fixing structure are provided on the metal mounting seats 3. The sealing structure is specifically a square sealing groove 8, with a sealing ring installed inside to achieve a seal with the gas box. The fixing structure consists of fixing holes evenly distributed on the metal mounting seats 3, through which bolts are inserted to achieve a fixed connection with the gas box.
[0060] When manufacturing the three-phase integrated insulating bushing, the metal mounting base 3, insert 5, and shielding structure 4 are first placed into the corresponding positions of the mold, and then the insulating material is poured into the mold. In this embodiment, the insulating material is epoxy resin. After the insulating material is formed, the mold is removed, and the three-phase integrated insulating bushing is completed. Then, the subsequent installation work is carried out.
[0061] During the installation of the three-phase integrated insulating bushing, first insert the sealing ring into the sealing ring groove 7 on the wall of the center hole 10, then insert the center conductor 2 into the center hole 10 inside the insert 5, and seal it with the sealing ring. At this point, the three-phase integrated insulating bushing is assembled. Then, the assembled three-phase integrated insulating bushing is fixed to the gas box wall of the gas-insulated switchgear using the fixing holes on the metal mounting base 3.
[0062] The embodiment of the gas-insulated switchgear provided by this utility model is as follows:
[0063] The gas-insulated switchgear of this utility model includes a gas box and a three-phase integrated insulating bushing mounted on the gas box. In this embodiment, the specific structure of the three-phase integrated insulating bushing is the same as that of the three-phase integrated insulating bushing in the embodiment described above, and will not be repeated here.
[0064] It should be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this utility model will not describe the various possible combinations separately.
[0065] Furthermore, various embodiments of this utility model can be combined in any way, as long as they do not violate the spirit of this utility model, they should also be regarded as the content disclosed by this utility model.
[0066] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. The patent protection scope of the present utility model shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present utility model shall also be included within the protection scope of the present utility model.
Claims
1. A three-phase integrated insulating bushing, characterized in that, The device includes a casting base in which a three-phase insert corresponding to the circuit is fixedly installed. The insert is pre-embedded in the casting base during the molding process. A central hole is provided on the insert, and a central conductor is fixedly inserted in the central hole. The central conductor and the insert are sealed together by a sealing element.
2. The three-phase integrated insulating bushing according to claim 1, characterized in that, The outer surface of the insert is provided with a surface extension structure.
3. The three-phase integrated insulating bushing according to claim 2, characterized in that, The surface extension structure is a protrusion provided on the outer surface of the insert.
4. The three-phase integrated insulating bushing according to claim 3, characterized in that, The protrusions are arranged around the corresponding central conductor, and annular grooves are formed between adjacent protrusions.
5. The three-phase integrated insulating bushing according to claim 4, characterized in that, The adjacent protrusions and annular grooves are smoothly connected.
6. The three-phase integrated insulating bushing according to any one of claims 1-5, characterized in that, A sealing ring groove is provided on the wall of the central hole of the insert, and the insert and the corresponding central conductor are sealed together by the sealing ring in the sealing ring groove.
7. The three-phase integrated insulating bushing according to any one of claims 1-5, characterized in that, Both ends of the insert protrude from the corresponding side of the casting base.
8. The three-phase integrated insulating bushing according to claim 7, characterized in that, A rounded corner structure is provided on the outer side of the end of the insert.
9. The three-phase integrated insulating bushing according to any one of claims 1-5, characterized in that, Each of the inserts is provided with a skirt on the outer periphery of the casting base to increase the creepage distance.
10. A gas-insulated switchgear, characterized in that, It includes a gas box and a three-phase integrated insulating bushing installed on the gas box, wherein the three-phase integrated insulating bushing is the three-phase integrated insulating bushing as described in any one of claims 1-9.