Device for preparing high-frequency harmonic tolerance experiment sample of epoxy resin impregnated paper material

Abstract

The utility model relates to a device for preparing an epoxy resin impregnated paper material high-frequency harmonic tolerance experiment sample, which comprises a plate-shaped electrode, a spherical electrode, and an upper cover, a mold cylinder and a bottom plate which are sequentially arranged from top to bottom, the plate-shaped electrode is arranged on the bottom plate, crepe paper is arranged on the upper side of the plate-shaped electrode, and the spherical electrode is arranged on the mold cylinder. A pressing and positioning part is arranged at the lower end of the mold cylinder, the edge of the crepe paper is pressed by the pressing and positioning part, a pouring hole, an exhaust hole and a threaded hole are formed in the upper cover, the upper end of a ball rod of the spherical electrode penetrates through the threaded hole and then is in threaded connection with a nut, and the edge of the upper cover is fixedly connected with the edge of the bottom plate through a connecting column. The device can control the distance between the spherical electrode and the plate-shaped electrode, can meet the requirements of subsequent experiments, solves the problem that the edge of the crepe paper is easy to curl, can ensure that the crepe paper is flat and is completely attached to the plate-shaped electrode, and can be dried and then subjected to vacuum pouring, so that the production efficiency is improved. Sample defects caused by bubbles generated during sample pouring can be avoided.

Description

Technical Field

[0001] This utility model relates to the field of epoxy resin impregnated paper material sample preparation technology, specifically a device for preparing epoxy resin impregnated paper material high-frequency harmonic tolerance test samples. Background Technology

[0002] Power system equipment has always been subject to power harmonics. High-voltage insulating bushings, operating in a harmonic environment for extended periods, generate significant harmonic losses. This can cause internal insulation heating, potentially leading to internal insulation damage and a severely reduced service life. It also impacts the safe and stable operation of power equipment. Therefore, during production, it is necessary to conduct high-frequency harmonic resistance tests on the epoxy resin impregnated paper samples used for high-voltage insulating bushings.

[0003] According to standard IEC 60455-2-2015, the electrodes used in the preparation of casting-type breakdown test samples are ball-plate combinations, where the high-voltage electrode is made of polished steel balls and the grounding electrode is a flat plate electrode, with electrode spacings of 0.5 mm, 1 mm, and 1.5 mm. However, the existing technology for preparing high-frequency harmonic withstand test samples of epoxy resin impregnated paper materials presents the following difficulties: 1. This sample needs to be molded in a mold, and the electrode spacing requirement is small, making it difficult to accurately control the plate gap and requiring high adjustability of the mold operation; 2. The copper plate electrode and the insulating paper must be completely bonded, because the flatness of the insulating paper cannot be changed after the epoxy resin liquid is poured; 3. Due to the special properties of epoxy resin impregnated paper materials, if there is moisture in the mold, air bubbles will be generated during the vacuum casting process, leading to sample defects. Utility Model Content

[0004] The purpose of this invention is to provide an apparatus for preparing high-frequency harmonic tolerance test samples of epoxy resin impregnated paper materials. It can control the spacing between the spherical electrode and the plate electrode to meet the requirements of subsequent experiments, and solves the problem of easy curling of the edges of crepe paper. It can ensure that the crepe paper is flat and completely adheres to the plate electrode. In addition, it can be dried first and then vacuum cast, which can avoid the generation of air bubbles during sample casting and thus avoid sample defects.

[0005] The objective of this utility model is achieved through the following technical solution:

[0006] An apparatus for preparing high-frequency harmonic tolerance test samples of epoxy resin impregnated paper material includes a plate electrode, a spherical electrode, and a top cover, a mold cylinder, and a bottom plate arranged sequentially from top to bottom. The plate electrode is disposed on the bottom plate, and wrinkled paper is provided on the upper side of the plate electrode. The lower end of the mold cylinder is provided with a clamping and positioning part, and the edge of the wrinkled paper is pressed by the clamping and positioning part. The top cover is provided with a pouring hole, a vent hole, and a threaded hole. The upper end of the ball rod of the spherical electrode passes through the threaded hole and is threadedly connected to a nut. The edge of the top cover and the edge of the bottom plate are connected and fixed by a connecting post.

[0007] The base plate is provided with a plate-shaped electrode positioning groove, and the plate-shaped electrode is located in the plate-shaped electrode positioning groove with its upper surface higher than the upper surface of the base plate.

[0008] The pressing and positioning part at the lower end of the mold cylinder includes a horizontal part and a vertical part, wherein the diameter of the vertical part is larger than the diameter of the mold cylinder and is connected to the lower end of the mold cylinder through the horizontal part, and the crepe paper is pressed down by the horizontal part.

[0009] The base plate is provided with a clamping and positioning groove, and the vertical cylindrical part is inserted into the clamping and positioning groove.

[0010] The connecting column is equipped with fixing nuts at both the upper and lower ends.

[0011] The advantages and positive effects of this utility model are as follows:

[0012] 1. The height of the spherical electrode of this invention can be adjusted, thereby controlling the distance between the spherical electrode and the plate electrode to meet the needs of subsequent sample experiments.

[0013] 2. The lower end of the mold cylinder of this utility model is provided with a pressing and positioning part to press the edge of the crepe paper on the upper side of the plate electrode, thereby solving the problem that the edge of the crepe paper is easy to curl, and ensuring that the crepe paper is flat and completely attached to the plate electrode.

[0014] 3. The base plate of this utility model is provided with a plate electrode positioning groove and a clamping positioning groove, which can ensure that the plate electrode and the mold cylinder will not move during the casting process, and at the same time, it can also ensure that the upper surface of the plate electrode and the clamping positioning part at the lower end of the mold cylinder clamp and fix the edge of the crepe paper.

[0015] 4. This utility model has an exhaust hole on the top cover for connecting to a vacuum pump and a pouring hole for connecting to a pouring system. In addition, during the preparation of this utility model, the moisture in the mold cylinder can be completely discharged through pressure swing drying, thereby ensuring that no air bubbles are generated during the vacuum pouring of the epoxy resin sample, which greatly reduces the defects in the sample preparation. Attached Figure Description

[0016] Figure 1 This is a schematic diagram illustrating the usage state of this utility model.

[0017] Figure 2 This is a cross-sectional view of the present invention.

[0018] Among them, 1 is the top cover, 2 is the bottom plate, 201 is the plate electrode positioning groove, 202 is the clamping positioning groove, 3 is the mold cylinder, 301 is the clamping positioning part, 3011 is the horizontal part, 3012 is the vertical cylinder part, 4 is the spherical electrode, 5 is the plate electrode, 6 is the nut, 7 is the vent hole, 8 is the pouring hole, 9 is the threaded hole, 10 is the pouring pipe, 11 is the pouring system, 12 is the drying system, 13 is the connecting column, and 14 is the crepe paper. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings.

[0020] like Figures 1-2 As shown, this utility model includes a plate-shaped electrode, a spherical electrode 4, and an upper cover 1, a mold cylinder 3, and a bottom plate 2 arranged sequentially from top to bottom, wherein... Figure 2 As shown, a plate-shaped electrode 5 (a copper plate electrode in this embodiment) is disposed on the base plate 2, and a crepe paper 14 is provided on the upper side of the plate-shaped electrode 5. The lower end of the mold cylinder 3 is provided with a clamping and positioning part 301 with an enlarged diameter, and the edge of the crepe paper 14 is pressed by the clamping and positioning part 301. This ensures that the crepe paper 14 is flat and fits the surface of the plate-shaped electrode 5. Figure 1 As shown, the upper cover 1 is provided with a pouring hole 8, a venting hole 7, and a threaded hole 9. The upper end of the ball rod of the spherical electrode 4 passes through the threaded hole 9 and is threadedly connected to a nut 6 to limit its height. Because the distance between the spherical electrode 4 and the plate electrode 5 is very important for subsequent experiments, this utility model can adjust the height of the spherical electrode 4 according to the actual situation through the above structure, thereby adjusting the distance between the spherical electrode 4 and the plate electrode 5. At the same time, the threaded connection can ensure the sealing requirements of subsequent vacuum pouring. The upper end of the spherical electrode 4 is connected to the power line to enable power supply. The pouring hole 8 is connected to the pouring pipe 10, and the pouring pipe 10 is connected to the pouring system 11. The pouring system 11 is a technology known in the art and is a commercially available product. The venting hole 7 is used to discharge gas during the pouring process. The edge of the upper cover 1 and the edge of the bottom plate 2 are connected and fixed by the connecting post 13 to achieve the clamping and fixing of the mold cylinder 3, the crepe paper 14, and the plate electrode 5.

[0021] like Figure 2As shown, in this embodiment, the base plate 2 is provided with a plate-shaped electrode positioning groove 201. The plate-shaped electrode 5 is disposed in the plate-shaped electrode positioning groove 201, and its upper surface is higher than the upper surface of the base plate 2. This ensures that the upper surface of the plate-shaped electrode 5 can cooperate with the clamping and positioning part 301 at the lower end of the mold cylinder 3 to clamp and press the wrinkled paper, while also ensuring that the plate-shaped electrode 5 is accurately positioned and will not move during the casting process. In addition, in this embodiment, the lower side of the base plate 2 is provided with a through hole for a power line to pass through, and the power line is connected to the plate-shaped electrode 5 to enable power supply.

[0022] like Figure 2 As shown, in this embodiment, the pressing and positioning part 301 at the lower end of the mold cylinder 3 includes a horizontal part 3011 and a vertical part 3012. The vertical part 3012 has a diameter larger than the diameter of the mold cylinder 3 and is connected to the lower end of the mold cylinder 3 through the horizontal part 3011. The crepe paper 14 is pressed by the horizontal part 3011, and the horizontal part 3011 needs to have sufficient distance to meet the pressing needs of plate electrodes 5 and crepe paper 14 with different diameter specifications.

[0023] like Figure 2 As shown, in this embodiment, the base plate 2 is provided with an annular pressing and positioning groove 202, and the pressing and positioning groove 202 is coaxially arranged on the outside of the plate electrode positioning groove 201. The vertical cylindrical part 3012 of the pressing and positioning part 301 is inserted into the pressing and positioning groove 202 to achieve positioning, thereby avoiding movement during the casting process. The depth design of the pressing and positioning groove 202 needs to ensure that the upper surface of the plate electrode 5 can cooperate with the pressing and positioning part 301 at the lower end of the mold cylinder 3 to clamp and press the wrinkled paper.

[0024] In this embodiment, the upper and lower ends of the connecting column 13 are provided with fixing nuts. Tightening the fixing nuts can clamp or loosen the upper cover 1 and the bottom plate 2, and the fixing clamping force can be adjusted according to actual needs.

[0025] The working principle of this utility model is as follows:

[0026] The following steps are included when using this utility model:

[0027] Step 1: Place the plate electrode 5 in the plate electrode positioning groove 201 of the base plate 2, and then lay crepe paper 14 of the same diameter on the upper surface of the plate electrode 5. The specific number of crepe paper 14 layers is set according to actual needs.

[0028] Step 2: Place the mold cylinder 3 on the base plate 2, wherein the vertical cylinder part 3011 of the lower end of the mold cylinder 3 pressing and positioning part 301 is inserted into the pressing and positioning groove 202 on the base plate 2 to achieve accurate positioning, and at the same time, the horizontal part 3011 of the pressing and positioning part 301 presses the edge of the crepe paper 14 so that it is flat and adheres to the surface of the plate electrode 5.

[0029] Step 3: Insert the upper end of the ball rod of the spherical electrode 4 into the threaded hole 9 on the upper cover 1. At this time, it is necessary to ensure that when the upper cover 1 is fastened on the mold cylinder 3, the spherical electrode 4 will not abut against the crepe paper 14, which would prevent the upper cover 1 from being installed.

[0030] Step 4: Place the upper cover 1 onto the mold cylinder 3, and use the connecting post 13 to connect the upper cover 1 and the base plate 2 to ensure the clamping and fixing of the mold cylinder 3, the crepe paper 14 and the plate electrode 5. Sealing elements such as sealing rings can be set between the upper cover 1 and the mold cylinder 3 and between the mold cylinder 3 and the base plate 2 to ensure the internal sealing of the mold cylinder 3. In addition, during this process, the clamping and fixing force can be adjusted by turning the fixing nuts at the upper and lower ends of the connecting post to avoid the clamping force being too small, while meeting the subsequent vacuum casting sealing requirements.

[0031] Step 5: Fine-tune the height of the spherical electrode 4 by screwing the upper end of the ball rod of the spherical electrode 4, that is, fine-tune the distance between the spherical electrode 4 and the plate electrode 5. In this embodiment, the fine thread pitch of the ball rod and the threaded hole 9 is designed to be 0.5mm to assist in controlling and adjusting the height. Alternatively, this invention can also assist in adjusting the height by setting scale lines on the upper end of the ball rod, so as to ensure that the distance between the spherical electrode 4 and the plate electrode 5 meets the design requirements.

[0032] Step 6: After the height of the spherical electrode 4 is determined, the nut 6 is threaded onto the upper end of the ball rod of the spherical electrode 4 to lock the height of the spherical electrode 4.

[0033] like Figure 1 As shown, the sample preparation process of this utility model can adopt pressure swing drying, vacuum casting and curing. First, the assembled structure is placed in the drying system 12. Then, by adjusting the temperature, vacuum degree and holding time of the drying system 12, the moisture of each component is quickly discharged through the exhaust port 7. In this embodiment, the time is expected to be 1 hour. After the drying process is completed and the temperature is lowered, vacuum casting is started. The exhaust port 7 is connected to the vacuum pipeline on the vacuum equipment. The vacuum pipeline is equipped with a vacuum control valve to control the on and off. This is a well-known technology in the field. The casting hole 8 is connected to the casting pipeline 10 and the casting is carried out into the mold cylinder 3 under vacuum. At this time, no bubbles are generated during the epoxy resin impregnation process, thereby ensuring that no defects are generated in the preparation process. Then the curing process is carried out.

Claims

1. An apparatus for preparing high-frequency harmonic withstand test samples of epoxy resin impregnated paper material, characterized in that: The device includes a plate electrode (5), a spherical electrode (4), and a top cover (1), a mold cylinder (3), and a bottom plate (2) arranged sequentially from top to bottom. The plate electrode (5) is located on the bottom plate (2), and a crepe paper (14) is provided on the upper side of the plate electrode (5). The mold cylinder (3) has a pressing and positioning part (301) at its lower end, and the edge of the crepe paper (14) is pressed by the pressing and positioning part (301). The top cover (1) has a pouring hole (8), a vent hole (7), and a threaded hole (9). The upper end of the ball rod of the spherical electrode (4) passes through the threaded hole (9) and is threadedly connected to a nut (6). The edge of the top cover (1) and the edge of the bottom plate (2) are connected and fixed by a connecting post (13).

2. The apparatus for preparing high-frequency harmonic tolerance test samples of epoxy resin impregnated paper material according to claim 1, characterized in that: The base plate (2) is provided with a plate-shaped electrode positioning groove (201), and the plate-shaped electrode (5) is located in the plate-shaped electrode positioning groove (201) with its upper surface higher than the upper surface of the base plate (2).

3. The apparatus for preparing high-frequency harmonic tolerance test samples of epoxy resin impregnated paper material according to claim 1, characterized in that: The pressing and positioning part (301) at the lower end of the mold cylinder (3) includes a horizontal part (3011) and a vertical part (3012), wherein the diameter of the vertical part (3012) is larger than the diameter of the mold cylinder (3) and is connected to the lower end of the mold cylinder (3) through the horizontal part (3011), and the crepe paper (14) is pressed by the horizontal part (3011).

4. The apparatus for preparing high-frequency harmonic tolerance test samples of epoxy resin impregnated paper material according to claim 3, characterized in that: The base plate (2) is provided with a pressing and positioning groove (202), and the vertical cylindrical part (3012) is inserted into the pressing and positioning groove (202).

5. The apparatus for preparing high-frequency harmonic tolerance test samples of epoxy resin impregnated paper material according to claim 1, characterized in that: The connecting column (13) is provided with fixing nuts at both the upper and lower ends.

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