Basin-type insulator and manufacturing method of basin-type insulator

Abstract

The invention relates to the field of insulators, in particular to a basin-type insulator and a manufacturing method of the basin-type insulator. The basin-type insulator and the manufacturing method of the basin-type insulator are used for solving the problems that the viscosity of a rubber coating between an existing center conductor and an existing insulator is low, it is difficult to guarantee the connection strength between the insulator and the center conductor, and the service life of the basin-type insulator is affected. The basin-type insulator comprises an insulator and a central conductor poured in the insulator, an elastic interlayer is arranged between the insulator and the central conductor, and an inner bonding layer is arranged between the elastic interlayer and the central conductor. Therefore, the bonding performance between the elastic interlayer and the central conductor is improved, the possibility that the insulator is stripped at the junction of the elastic interlayer and the central conductor is reduced, and the service life of the basin-type insulator is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of insulators, and particularly to a pot-shaped insulator and a manufacturing method thereof. Background Art

[0002] Gas-insulated combined electrical equipment (GIS) and gas-insulated transmission lines (GIL) have been widely applied to the power grid system in China. The pot-shaped insulator is a relatively key component, mainly playing the roles of insulation, support, and isolation of gas chambers. The pot-shaped insulator usually consists of a central conductor, an outer flange, and an insulator. During specific production, the central conductor and the flange are placed in a mold, and an epoxy resin material is used for casting. After the epoxy resin material is cured, an insulator in a pot shape as a whole is formed. However, the cured insulator is prone to stress concentration, resulting in problems such as the peeling of the central conductor from the insulating material.

[0003] The Chinese invention patent with the publication number of CN105448439A discloses a method for interfacial treatment of extra-high voltage pot-shaped insulators. The method includes the following steps: applying an interfacial coating on the side surface of the central conductor, and after preliminary curing, placing it in a mold and using an epoxy resin material for casting. Among them, the interfacial agent of the interfacial coating consists of room-temperature vulcanized rubber, conductive particles, and a solvent. The interfacial coating can play a role in buffering stress and reducing stress concentration at the insulator. However, the rubber-based coating has a low viscosity, and it is difficult to ensure the interfacial bonding strength with the central conductor when brush-coated on the central conductor, which is prone to cause the peeling of the insulator from the central conductor and affect the service life of the pot-shaped insulator. Summary of the Invention

[0004] The purpose of the present invention is to provide a pot-shaped insulator to solve the problem that the rubber coating between the existing central conductor and the insulator has a low viscosity, it is difficult to ensure the connection strength between the insulator and the central conductor, and it affects the service life of the pot-shaped insulator. The purpose of the present invention is also to provide a manufacturing method of a pot-shaped insulator to solve the problem that the rubber coating between the existing central conductor and the insulator has a low viscosity, it is difficult to ensure the connection strength between the insulator and the central conductor, and it affects the service life of the pot-shaped insulator.

[0005] A pot-shaped insulator of the present invention includes an insulator and a central conductor cast in the insulator. There is an elastic interlayer between the insulator and the central conductor, and an inner bonding layer is provided between the elastic interlayer and the central conductor.

[0006] Further, the surface of the central conductor is a rough surface treated by sandblasting.

[0007] Further, an outer bonding layer is provided between the elastic interlayer and the insulator.

[0008] Further, both the inner bonding layer and the outer bonding layer are epoxy primer layers treated with a coupling agent.

[0009] Further, the thickness of the middle part of the insulator near the center conductor is thicker than that of its edge part.

[0010] Further, an annular stress relief groove is provided at the edge of the center conductor near the insulator.

[0011] Further, an outer flange is provided on the outside of the insulator, and the insulator and the outer flange are in concave-convex fit. A release agent layer is provided on the inner side surface of the outer flange to ensure that there is no adhesive force between the insulator and the outer flange.

[0012] The present invention proposes an improved technical solution, in which an inner bonding layer is provided between the elastic interlayer and the center conductor. In this way, the bonding performance between the elastic interlayer and the center conductor is improved, the possibility of the insulator peeling at the junction of the elastic interlayer and the center conductor is reduced, and the service life of the pot-type insulator is extended.

[0013] Another aspect of the present invention also provides a manufacturing method of a pot-type insulator, including the following steps: brushing an elastic coating on the surface of the center conductor to form an elastic interlayer, placing the center conductor in a mold, and pouring with an epoxy resin material to obtain an insulator. Before brushing the elastic coating, a bonding coating is first brushed on the surface of the center conductor to form an inner bonding layer so as to ensure the interfacial bonding force between the elastic interlayer and the center conductor.

[0014] Further, before brushing the bonding coating on the center conductor, the surface of the center conductor is sandblasted.

[0015] Further, before pouring with the epoxy resin material, a bonding coating is brushed on the elastic interlayer to form an outer bonding layer.

[0016] Further, both the inner bonding layer and the outer bonding layer are epoxy primer layers treated with a coupling agent.

[0017] Further, the thickness of the middle part of the insulator near the center conductor is thicker than that of its edge part.

[0018] Further, an annular stress relief groove is provided at the edge of the center conductor near the insulator.

[0019] Further, an outer flange that is in concave-convex fit with the insulator is provided on the outside of the insulator. Before pouring, a release agent is brushed on the inner side surface of the outer flange to ensure that there is no adhesive force between the insulator and the outer flange.

[0020] The present invention proposes an improved technical solution. Before brushing the elastic coating, a bonding coating is first brushed on the surface of the central conductor to form an inner bonding layer. In this way, the bonding performance between the elastic interlayer and the central conductor is improved, the possibility of the insulator peeling at the junction of the elastic interlayer and the central conductor is reduced, and the service life of the pot-type insulator is extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a half-sectional view of a pot-type insulator according to the present invention; Figure 2 is a schematic structural view of an inner bonding layer, an elastic interlayer, and an outer bonding layer provided between the central conductor and the insulator; Figure 3 is a schematic structural view of a release agent layer provided between the insulator and the outer flange.

[0022] In the figure: 1, central conductor; 11, stress relief groove; 2, insulator; 21, circular boss; 3, outer flange; 31, circular groove; 4, inner bonding layer; 5, elastic interlayer; 6, release agent layer; 7, outer bonding layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The present invention proposes an improved technical solution for the problems existing in the above technical solution: an inner bonding layer is provided between the elastic interlayer and the central conductor. In this way, the bonding performance between the elastic interlayer and the central conductor is improved, the possibility of the insulator peeling at the junction of the elastic interlayer and the central conductor is reduced, and the service life of the pot-type insulator is extended.

[0024] A pot-type insulator of the present invention includes an insulator 2 as shown in Figure 1 and a central conductor 1 cast in the insulator 2. An elastic interlayer 5 as shown in Figure 2 is provided between the insulator 2 and the central conductor 1. The elastic interlayer 5 in this embodiment is a high-elastic rubber interlayer. As an intermediate layer, the elastic interlayer 5 can absorb and disperse the stress generated due to temperature changes, mechanical vibrations, etc., and reduce the stress concentration at the interface or on the insulator 2. An inner bonding layer 4 is provided between the elastic interlayer 5 and the central conductor 1. In this way, the bonding performance between the elastic interlayer 5 and the central conductor 1 is improved, the possibility of the insulator 2 peeling at the junction of the elastic interlayer 5 and the central conductor 1 is reduced, and the service life of the pot-type insulator is extended.

[0025] In this embodiment, the surface of the central conductor 1 is a rough surface treated by sandblasting. In this way, the adhesion strength of the inner bonding layer 4 can be improved, and the bonding reliability between the central conductor 1 and the insulator 2 is further ensured. In addition, in other embodiments, sandblasting treatment may not be performed, and the bonding coating may be directly brushed on the surface of the central conductor to form the inner bonding layer.

[0026] In this embodiment, an outer bonding layer 7 is provided between the elastic interlayer 5 and the insulator 2. In this way, the interfacial bonding force between the elastic interlayer 5 and the insulator 2 is improved, and the peeling of the insulator 2 here is avoided.

[0027] In this embodiment, both the inner bonding layer 4 and the outer bonding layer 7 are epoxy primer layers treated with a coupling agent. The coupling agent can improve the interfacial compatibility between the epoxy primer and the inorganic material, ensuring the bonding reliability of the bonding layer. The coupling agent can also increase the hardness, wear resistance and impact resistance of the epoxy primer, and can also ensure the resistance of the epoxy primer to chemical substances, further improving the physical and chemical properties of the bonding layer. In addition, in other embodiments, the inner bonding layer and the outer bonding layer can also be ordinary epoxy primer layers, as long as the bonding is reliable. Of course, in another embodiment, the inner bonding layer can be an epoxy primer layer treated with a coupling agent, and the outer bonding layer can be an ordinary epoxy primer layer.

[0028] In this embodiment, the thickness of the middle part of the insulator 2 close to the center conductor 1 is thicker than the thickness of its edge part. In this way, during the curing process of the epoxy resin material, it will shrink towards the center conductor 1, thereby improving the interfacial bonding force between the epoxy resin and the center conductor 1, avoiding the peeling of the center conductor 1 from the insulating material, and further improving the service life of the pot-type insulator. In addition, in other embodiments, the thickness of the middle part of the insulator close to the center conductor can also be the same as the thickness of its edge part; of course, in another embodiment, the thickness of the middle part of the insulator close to the center conductor can also be smaller than the thickness of its edge part.

[0029] In this embodiment, a circular stress relief groove 11 is provided at the edge of the center conductor 1 close to the insulator 2. The epoxy resin material will shrink during the curing process. If the relief groove is not provided, the compressive stress generated by the shrinkage acts on the center conductor 1, and a corresponding reaction force will also be generated on the insulator 2. After the relief groove is provided, the groove wall on the side of the relief groove close to the center conductor 1 can undergo a certain deformation under the action of the compressive stress. In this way, the compressive stress only acts on this side of the groove wall, relieving the curing stress of the insulating material and further avoiding the generation of cracks on the insulator 2.

[0030] In this embodiment, as Figure 3As shown in the figure, an outer flange 3 is provided on the outer side of the insulator 2, and the insulator 2 and the outer flange 3 are in concave-convex fit. A release agent layer 6 is provided on the inner side surface of the outer flange 3 to ensure that there is no adhesive force between the insulator 2 and the outer flange 3. If the release agent layer 6 is not brushed, during pouring, due to the shrinkage of the epoxy resin, the central conductor 1 and the outer flange 3 will pull on the insulator 2 placed in the middle, and then tensile stress will be formed in the insulator 2. In severe cases, it will cause cracking of the epoxy resin insulator 2. In this embodiment, brushing the release agent on the inner side surface of the outer flange 3 ensures that there is no bonding relationship between the outer flange 3 and the insulator 2. In this way, the formation of tensile stress on the insulator 2 can be avoided, the cracking of the insulator 2 can be avoided, and the service life of the pot-type insulator is improved. At both ends of the inner side surface of the outer flange 3 in this embodiment, annular bosses are provided to form a circular groove 31 in the middle. After the epoxy resin pouring is completed, a circular boss 21 matching the circular groove 31 will be formed on the insulator 2 to achieve the assembly of the two.

[0031] On the other hand, the present invention also provides a manufacturing method of a pot-type insulator. The manufacturing method of the pot-type insulator includes the following steps: brushing an elastic coating on the surface of the central conductor 1 to form an elastic interlayer 5, placing the central conductor 1 in a mold, and using an epoxy resin material for pouring to obtain the insulator 2. Before brushing the elastic coating, a bonding coating is first brushed on the surface of the central conductor 1 to form an inner bonding layer 4 to ensure the interfacial bonding force between the elastic interlayer 5 and the central conductor 1. In this way, the bonding performance between the elastic interlayer 5 and the central conductor 1 is improved, the possibility of the insulator 2 peeling off at the junction of the elastic interlayer 5 and the central conductor 1 is reduced, and the service life of the pot-type insulator is extended.

[0032] In this embodiment, before brushing the inner bonding layer 4 on the central conductor 1, the outer side surface of the central conductor 1 is sandblasted. In this way, the roughness of the surface of the central conductor 1 is increased, the adhesion strength of the inner bonding layer 4 can be improved, and the bonding reliability between the central conductor 1 and the insulator 2 is further ensured. In addition, in other embodiments, sandblasting treatment may not be performed, and the inner bonding layer 4 may be directly brushed on the surface of the central conductor 1.

[0033] Before pouring the epoxy resin material, a bonding coating is brushed on the elastic interlayer 5 to form an outer bonding layer 7. In this way, the interfacial bonding force between the elastic interlayer 5 and the insulator 2 is improved, and the peeling of the insulator 2 at this place is avoided.

[0034] In this embodiment, both the inner bonding layer 4 and the outer bonding layer 7 are epoxy primer layers treated with a coupling agent. The coupling agent can improve the interfacial compatibility between the epoxy primer and the inorganic material, ensuring the bonding reliability of the bonding layer. The coupling agent can also increase the hardness, wear resistance, and impact resistance of the epoxy primer, and can also ensure the resistance of the epoxy primer to chemical substances, further improving the physical and chemical properties of the bonding layer. In addition, in other embodiments, the inner bonding layer and the outer bonding layer can also be ordinary epoxy primer layers, as long as the bonding is reliable. Of course, in another embodiment, the inner bonding layer can be an epoxy primer layer treated with a coupling agent, and the outer bonding layer can be an ordinary epoxy primer layer.

[0035] In this embodiment, the thickness of the middle part of the insulator 2 near the center conductor 1 is thicker than the thickness of its edge part. In this way, during the curing process of the epoxy resin material, it will shrink towards the center conductor 1, thereby improving the interfacial bonding force between the epoxy resin and the center conductor 1, avoiding the peeling of the center conductor 1 from the insulating material, and further increasing the service life of the pot-type insulator. In addition, in other embodiments, the thickness of the middle part of the insulator near the center conductor can also be the same as the thickness of its edge part; of course, in another embodiment, the thickness of the middle part of the insulator near the center conductor can also be smaller than the thickness of its edge part.

[0036] In this embodiment, an annular stress relief groove 11 is provided at the edge of the center conductor 1 near the insulator 2. The epoxy resin material will shrink during the curing process. If no relief groove is provided, the compressive stress generated by the shrinkage acts on the center conductor 1, and a corresponding reaction force will also be generated on the insulator 2. After the relief groove is provided, the groove wall on the side of the relief groove near the center conductor 1 can undergo a certain deformation under the action of the compressive stress. In this way, the compressive stress only acts on this side of the groove wall, relieving the curing stress of the insulating material and further avoiding the generation of cracks on the insulator 2.

[0037] In this embodiment, as Figure 3As shown, an outer flange 3 that mates with the insulator 2 in a concave-convex manner is provided on the outside of the insulator 2. Before pouring, a release agent is brushed on the inner side surface of the outer flange 3 to ensure that there is no adhesive force between the insulator 2 and the outer flange 3. If the release agent is not brushed, during pouring, due to the shrinkage of the epoxy resin, the central conductor 1 and the outer flange 3 will pull on the coiled insulator 2 placed in the middle, and then tensile stress will be formed in the insulator 2. In severe cases, it will cause cracking of the epoxy resin insulator 2. In this embodiment, brushing the release agent on the inner side surface of the outer flange 3 ensures that there is no bonding relationship between the outer flange 3 and the epoxy resin. Thus, the formation of tensile stress between the epoxy resin insulators 2 can be avoided, the cracking of the epoxy resin insulator 2 is avoided, and the service life of the pot insulator 2 is improved. At both ends of the inner side surface of the outer flange 3 in this embodiment, annular bosses are provided to form a circular groove 31 in the middle. After the epoxy resin is poured, a circular boss 21 that mates with the circular groove 31 will be formed on the insulator 2, thereby realizing the assembly of the two.

[0038] The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention is subject to the claims. All equivalent structural changes made by using the description and drawings of the present invention should, by the same token, be included in the protection scope of the present invention.

Claims

1. A pot-type insulator, comprising an insulator and a central conductor cast in the insulator, with an elastic interlayer between the insulator and the central conductor, characterized in that: An inner bonding layer is arranged between the elastic interlayer and the central conductor.

2. The pot-type insulator according to claim 1, characterized in that: The surface of the central conductor is a rough surface processed by sandblasting.

3. The pot-type insulator according to claim 1 or 2, characterized in that: An outer bonding layer is arranged between the elastic interlayer and the insulator.

4. The pot-type insulator according to claim 3, characterized in that: The inner adhesive layer and the outer adhesive layer are both epoxy primer layers treated with coupling agents.

5. The pot-type insulator according to claim 1 or 2, characterized in that: The thickness of the middle portion of the insulator close to the center conductor is thicker than that of the edge portion thereof.

6. The pot-type insulator according to claim 1 or 2, characterized in that: An annular stress relief groove is arranged at the edge of the central conductor close to the insulator.

7. The pot-type insulator according to claim 1 or 2, characterized in that: An outer flange is arranged on the outer side of the insulator, and the insulator and the outer flange are matched in a concave-convex manner. A release agent layer is arranged on the inner side surface of the outer flange to ensure that there is no adhesive force between the insulator and the outer flange.

8. A method for manufacturing a pot-type insulator, comprising the following steps: An elastic coating is applied on the surface of the center conductor to form an elastic interlayer, the center conductor is placed in a mold, and epoxy resin material is used for casting to obtain an insulator, which is characterized in that before applying the elastic coating, an adhesive coating is first applied on the surface of the center conductor to form an inner adhesive layer so as to ensure the interface bonding force between the elastic interlayer and the center conductor.

9. The method for manufacturing a pot-type insulator according to claim 8, characterized in that: Before applying the bonding coating to the center conductor, the surface of the center conductor is sandblasted.

10. The method for manufacturing a pot-type insulator according to claim 8 or 9, characterized in that: Before pouring the epoxy resin material, a bonding coating is applied on the elastic interlayer to form an outer bonding layer.

11. The method for manufacturing a pot-type insulator according to claim 10, characterized in that: The inner adhesive layer and the outer adhesive layer are both epoxy primer layers treated with coupling agents.

12. The method for manufacturing a pot-type insulator according to claim 8 or 9, characterized in that: The thickness of the middle portion of the insulator close to the center conductor is thicker than that of the edge portion thereof.

13. The method for manufacturing a pot-type insulator according to claim 8 or 9, characterized in that: An annular stress relief groove is arranged at the edge of the central conductor close to the insulator.

14. The method for manufacturing a pot-type insulator according to claim 8 or 9, characterized in that: An outer flange matching the insulator is arranged on the outer side of the insulator. Before pouring, a mold release agent is first applied on the inner side of the outer flange to ensure that there is no adhesion between the insulator and the outer flange.

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