Cooperative pressurization structure, self-repairing hot pressing device and high-voltage insulator forming process

Abstract

The invention discloses a collaborative pressurizing structure, a self-repairing hot-pressing device and a high-voltage insulator forming process, the collaborative pressurizing structure comprises a frame and a control mechanism, and further comprises an equipment main body mounted in an inner cavity of the frame and a hot-pressing mold mounted in the inner cavity of the frame, and a side sliding block comprises a sliding block main body and an inner conical surface arranged at one end of the sliding block main body; the surface of the inner conical surface is provided with a self-repairing assembly, four sets of auxiliary linkage mechanisms installed on the periphery of the equipment body, a main linkage mechanism installed at the bottom of an inner cavity of the frame and a distance adjusting assembly installed at the top of the frame, and the self-repairing assembly, the four sets of auxiliary linkage mechanisms, the main linkage mechanism and the distance adjusting assembly are used for driving the upper sliding block to do linear reciprocating motion in the axial direction of the die sleeve. Through axial pressurization of the lower sliding block and the upper sliding block and radial pressurization of the side sliding block, the problems of forming and demolding of the V-shaped umbrella edge and the deep-edge umbrella skirt in integrated forming are solved, the overall uniformity and durability of the high-voltage insulator are improved, and the problem that the binding force of the umbrella skirt and the columnar binding surface is weak in step-by-step forming is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of insulator manufacturing equipment, and specifically, to a cooperative pressurization structure, a self-repairing hot pressing device, and a high-voltage insulator forming process. Background Art

[0002] A hot press promotes physical and chemical changes in insulating materials under high temperature and high pressure conditions, significantly improving the density, mechanical strength, and electrical performance of products. However, the complex geometric structure of high-voltage insulators (such as the combination of multiple groups of functionalized umbrella skirts and cylinders) leads to two core problems: uneven material distribution: at the edges of the umbrella skirts (such as special-shaped structures like deep-ribbed umbrellas and aerodynamic umbrellas), due to poor material fluidity, the density is significantly lower than that in the cylinder area; demolding stress cracking: cracks are likely to occur between the formed part and the mold due to the difference in shrinkage stress, especially in the high aspect ratio umbrella skirt parts (such as anti-icing umbrellas with sharp corners or grooves).

[0003] Patent CN202311393253.5 discloses an insulator production technology. By setting a rotatable movable part on the mold assembly and controlling the rotation of the mold body along the horizontal and vertical planes during the forming process, the uniformity of raw material distribution is improved, thereby optimizing the production quality.

[0004] The prior art improves the raw material distribution by the rotating mold method, but there are still problems: high equipment requirements, a precise control system is needed to maintain multi-directional rotation under high temperature and high pressure, resulting in a sharp increase in cost; insufficient stability, air bubbles or density gradients are easily introduced during the dynamic forming process, affecting product consistency; the cracking problem is not solved, and rotation cannot eliminate the stress concentration during demolding. In view of this, the present invention provides a multi-slider integral forming mold, which improves the density of the insulator through multi-directional pressurization in the axial and radial directions, reduces cracking through distributed demolding of the side sliders, and delays the wear of the conical surface and extends the effective service life of the side sliders by using a conical side slider with self-repairing function. Summary of the Invention

[0005] To solve the above technical problems, on the one hand, the present invention provides a cooperative pressurization structure and a self-repairing hot pressing device. In the technical solution of the present invention, it includes a frame and a control mechanism, and further includes:

[0006] The equipment main body installed in the inner cavity of the frame, the equipment main body includes a rear box body fixedly connected to the top of the inner cavity of the frame, a front box body hinged to the side of the rear box body, and a heating, heat preservation, and heat dissipation mechanism;

[0007] The hot pressing mold installed in the inner cavity of the frame, the hot pressing mold includes a mold sleeve, an upper slider and a lower slider axially slidably connected to both ends of the mold sleeve respectively, and four groups of side sliders circumferentially distributed on the side wall of the mold sleeve and radially slidably connected to the mold sleeve;

[0008] The side slider includes a slider body and an inner conical surface provided at one end of the slider body. A self-repairing component is provided on the surface of the inner conical surface. The self-repairing component includes a porous structure, a wear-resistant layer, and self-repairing capsules loaded in the porous structure;

[0009] Among them, the conical angle of the inner conical surface is 5°-10°;

[0010] Four sets of secondary linkage mechanisms are installed around the equipment body. The secondary linkage mechanisms are electrically connected to the control mechanism to drive the side slider to reciprocate linearly along the radial direction of the die sleeve;

[0011] The main linkage mechanism is installed at the bottom of the inner cavity of the frame. The main linkage mechanism is electrically connected to the control mechanism to drive the lower slider to reciprocate linearly along the axial direction of the die sleeve;

[0012] The distance adjustment component is installed at the top of the frame and is used to drive the upper slider to reciprocate linearly along the axial direction of the die sleeve.

[0013] Furthermore, in the technical solution of the present invention, a hot pressing cavity is provided in the middle of the front box body and the rear box body. When the front box body and the rear box body are closed, installation grooves are provided at the same horizontal height in the middle of the four sides of the equipment body. An installation hole is provided at the bottom of the installation groove along the radial direction, and an adjustment channel communicating with the hot pressing cavity is provided at the bottom of the installation hole.

[0014] Furthermore, in the technical solution of the present invention, the die sleeve includes a die sleeve body. A die cavity is provided inside the die sleeve body. Upper sliding holes and lower sliding holes communicating with the outside are respectively provided at the top and the bottom of the die cavity. Four sets of side sliding holes are provided circumferentially in the umbrella skirt distribution area of the die cavity. An outer conical surface adapted to the inner conical surface is provided at one end of the side sliding hole communicating with the die cavity.

[0015] Furthermore, in the technical solution of the present invention, the upper slider has the same diameter as the upper sliding hole and is slidably connected in the upper sliding hole. The lower slider has the same diameter as the lower sliding hole and is slidably connected in the lower sliding hole. The four sets of side sliders have the same diameter as the side sliding holes and are respectively slidably connected in the side sliding holes.

[0016] Furthermore, in the technical solution of the present invention, the self-repairing component is prepared by the following steps:

[0017] Laser processing of micropores: The surface of the inner conical surface is processed by a femtosecond laser with a wavelength of 1030 nm and a pulse energy of 50 μJ to form a honeycomb-like microporous porous structure;

[0018] Vacuum impregnation: Under a vacuum of 10 -3 Pa, the inner conical surface is immersed in the ethanol solvent of the self-repairing capsule suspension liquid. The self-repairing capsules are pressed into the porous structure by capillary action, taken out, and dried to obtain an intermediate;

[0019] Surface sealing: Deposit a wear-resistant layer on the surface of the intermediate through atomic layer deposition (ALD).

[0020] Among them, the wear-resistant layer is more preferably an aluminum oxide film with a thickness of 5 - 10 nm.

[0021] Furthermore, in the technical solution of the present invention, the self-healing capsules are prepared through the following steps:

[0022] Core material dispersion: Disperse the core material in the PI precursor solution with a solid content of 15%.

[0023] Atomization granulation: The inlet temperature is 180 °C, and the outlet temperature is 80 °C to form capsules with a particle size distribution of 1 - 3 μm.

[0024] High-temperature curing: Heat-treat at 300 °C for 2 hours to crosslink and cure the capsule wall to obtain self-healing capsules.

[0025] Among them, the number-average molecular weight of the PI precursor is 5000 - 15000 g / mol, the dispersity is 1.1 - 1.6, the wall thickness of the self-healing capsule 2PI is 0.2 μm, and the response mechanical stress strength is 15 MPa ± 0.1 MPa.

[0026] Furthermore, in the technical solution of the present invention, the self-healing capsules include a capsule wall and a core encapsulated within the capsule wall.

[0027] Furthermore, in the technical solution of the present invention, the core is more preferably MoS2 nanosheets, and the layer thickness of the MoS2 nanosheets < 10 nm.

[0028] Furthermore, in the technical solution of the present invention, the secondary linkage mechanism includes a hydraulic press detachably connected in the installation groove, a linear bearing installed in the placement hole, and a driving rod partially extending into the adjustment channel. The hydraulic press drives the driving rod to perform reciprocating linear motion.

[0029] A high-voltage insulator forming process using the above hot pressing forming device includes the following steps:

[0030] Loading: Place the lower slider in the lower slide hole and leave some margin. Add insulator raw materials into the mold cavity from the upper slide hole, level it until the filling height is within the upper slide hole, place several groups of side sliders in the corresponding side slide holes respectively, and then push the upper slider along the upper slide hole to compact.

[0031] Mold installation: Place the loaded hot pressing mold in the hot pressing cavity, control the distance adjustment component and the main linkage mechanism to abut against the upper and lower ends of the hot pressing mold respectively, close the front box body, and install the secondary linkage mechanism in the installation groove and make the driving rod abut against the outer end of the side slider.

[0032] Program control: The secondary linkage mechanism synchronously drives several groups of side sliders to be radially pressed into the light contact position, compacts the powder body and seals the mold cavity, and the pressure application range is 5 - 10 MPa; heat to the target temperature, and at the same time, the main linkage mechanism drives the downward hole to move upward to apply pressure to the raw materials in the inner cavity of the mold cavity, and the pressure application range is 100 - 300 MPa; the secondary linkage mechanism synchronously applies pressure to the side sliders to maintain the radial pressure, and the pressure application range is 20 - 90 MPa; during the heat preservation and pressure holding stage, the dynamic adjustment range of the side slider pressure is ±5 MPa;

[0033] Demolding: After the temperature drops to room temperature, the secondary linkage mechanism controls four groups of side sliders at the same horizontal height to synchronously retract 0.3 - 0.5 mm, and the two groups of diagonal side sliders alternately retract 2 mm each. All side sliders synchronously retract until they are completely separated. The main linkage mechanism controls the removal of the pressure on the downward slider, opens the front box body, takes out the hot pressing mold, removes each group of mold cores, opens the mold sleeve, and takes out the hot pressed parts to complete the hot pressing of the high-voltage insulator.

[0034] Effective gain: In the technical solution of the present invention, by setting a multi-slider mold, axial pressure is applied through the downward slider and the upward slider, and radial pressure is applied in cooperation with the side sliders, so as to solve the problems of forming and demolding of the V-shaped umbrella edge and the deep rib umbrella skirt in one-piece molding, improve the overall uniformity and durability of the high-voltage insulator, and avoid the problem of weak bonding force at the bonding surface between the umbrella skirt and the column in step-by-step molding;

[0035] By setting the cooperation of the inner conical surface and the outer conical surface on the inner side of the side sliding hole, a conical surface interlocking structure is formed to improve the sealing performance of the mold cavity and prevent powder leakage under high pressure;

[0036] The inner conical surface is treated by laser to form a porous structure, and self-healing capsules internally wrapped with MoS2 nanosheets are loaded in the porous structure, and a wear-resistant layer is deposited outside the porous structure. As the wear-resistant layer wears, when the shear force received by the self-healing capsule ≥ 15 MPa, the capsule wall ruptures, and the capsule core is released to repair the inner conical surface, improving the effective service life of the inner conical surface.

[0037] Other features and advantages of the present invention will be described in the subsequent description. Brief Description of the Drawings

[0038] In order to more clearly illustrate the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0039] Figure 1 It is a schematic structural diagram of the cooperative pressure application structure and the self-healing hot pressing device of the present invention;

[0040] Figure 2Schematic diagram of the main structure of the device of the present invention;

[0041] Figure 3 Schematic diagram of the hot pressing die structure of the present invention;

[0042] Figure 4 Schematic diagram of the half-sectional structure of the hot pressing die sleeve of the present invention;

[0043] Figure 5 Schematic diagram of the partially sectional structure of the side slider of the present invention;

[0044] Figure 6 For the present invention Figure 5 Enlarged schematic diagram of part A;

[0045] Figure 7 For the present invention Figure 6 Enlarged schematic diagram of part B;

[0046] Figure 8 Schematic diagram of the structure of the secondary linkage mechanism of the present invention.

[0047] In the figure: 1 main body of the device, 11 front box body, 12 heating cavity, 13 hot pressing cavity, 14 heat insulation layer, 15 rear box body, 16 placement hole, 17 adjustment channel, 18 installation groove, 2 hot pressing die, 21 lower slider, 22 die sleeve, 221 die sleeve main body, 222 upper sliding hole, 223 die cavity, 224 side sliding hole, 225 lower sliding hole, 23 side slider, 231 slider main body, 232 inner conical surface, 233 porous structure, 234 wear-resistant layer, 235 self-healing capsule, 2351 capsule wall, 2352 capsule core, 24 upper slider, 3 main linkage mechanism, 4 secondary linkage mechanism, 41 hydraulic press, 42 linear bearing, 43 driving rod, 5 frame, 6 distance adjustment component. Specific embodiments

[0048] To make the objectives, features, and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described below are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0049] One aspect of the embodiments of the present invention provides a cooperative pressing structure and a self-healing hot pressing device, including a device main body 1, a hot pressing die 2, a main linkage mechanism 3, four groups of secondary linkage mechanisms 4, a frame 5, a distance adjustment component 6, and a control component.

[0050] Please refer to FIG. 1. The distance adjustment component 6 is installed on the top of the frame 5 and abuts against the upper end of the hot pressing die 2 after adjustment. The main linkage mechanism 3 is installed at the bottom of the inner cavity of the frame 5 to provide an axial driving force for the hot pressing die 2. The equipment main body 1 is installed at the top of the inner cavity of the frame 5 for heating, heat preservation and constant temperature of the hot pressing die 2. The hot pressing die 2 is installed in the inner cavity of the equipment main body 1. Four sets of secondary linkage mechanisms 4 are respectively installed in the middle positions of the side walls of the equipment main body 1 to provide a radial driving force for the hot pressing die 2.

[0051] Please refer to Figure 2 , the equipment main body 1 includes a rear box body 15 fixedly connected to the top of the inner cavity of the frame 5 and a front box body 11 hinged to one side of the rear box body 15. The front box body 11 and the rear box body 15 in the closed state together form a cuboid A. A hot pressing cavity 13 is opened in the middle of the cuboid A. An heating cavity 12, a heat preservation layer 14 and a heat dissipation component are coaxially arranged in sequence outside the hot pressing cavity 13. The heating cavity 12 and the heat dissipation component are both electrically connected to the control component for controlling the temperature inside the hot pressing cavity 13.

[0052] Specifically, mounting grooves 18 are opened on four side surfaces of the cuboid A. An installation hole 16 is opened at the bottom of the mounting groove 18 close to one side of the hot pressing cavity 13. An adjustment channel 17 communicating with the hot pressing cavity 13 is opened at the bottom of the installation hole 16.

[0053] It should be noted that since the cuboid A includes two parts, the front box body 11 and the rear box body 15, two sets of mounting grooves 18 are respectively opened on the opposite sides of the front box body 11 and the rear box body 15, that is, the front and rear end faces of the cuboid A. The other two sets of mounting grooves 18 are opened on the two sides jointly formed by the front box body 11 and the rear box body 15, that is, the left and right side faces of the cuboid A. That is to say, the mounting grooves 18, the installation holes 16 and the adjustment channels 17 located on the left and right side faces of the cuboid A are consistent in shape with those on the front and rear end faces when the front box body 11 and the rear box body 15 are closed. When the front box body 11 is opened, the mounting grooves 18, the installation holes 16 and the adjustment channels 17 are separated by the connection surface of the front box body 11 and the rear box body 15 as the axis of symmetry, with half opened on the side wall of the front box body 11 and half opened on the side wall of the rear box body 15. The heights of the four sets of mounting grooves 18 are kept consistent.

[0054] Please refer to Figure 3 to FIG. 4. The hot pressing die 2 includes a die sleeve 22. An upper slider 24 and a lower slider 21 are respectively axially slidably connected to the upper and lower ends of the die sleeve 22. Four sets of side sliders 23 are radially slidably connected to the side wall of the die sleeve 22.

[0055] It should be noted that the four sets of side sliders 23 are located at the same horizontal height, and the adjacent two sets are arranged at an interval of 90°. They jointly form a side slider series to perform radial pressing on a certain height area. In other embodiments, multiple sets of side slider series with different horizontal heights can be respectively set in areas such as V-shaped umbrella edges, deep rib umbrella skirts or other areas where it is difficult to form or demold according to requirements.

[0056] Specifically, the mold sleeve 22 includes a mold sleeve body 221. A mold cavity 223 is provided inside the mold sleeve body 221. An upper sliding hole 222 and a lower sliding hole 225 communicating with the outside are respectively provided at the top and bottom of the mold cavity 223. Four groups of side sliding holes 224 are circumferentially and spaced apart on the side wall of the umbrella skirt part of the mold cavity 223. An outer conical surface is provided on the side of the side sliding hole 224 close to the mold cavity 223.

[0057] It should be noted that the mold sleeve 22 is provided with a parting line, which longitudinally divides the mold sleeve 22 into two groups along the axis, and the parting line is provided in the middle of two adjacent groups of side sliding holes 224.

[0058] Please refer to Figures 5 to 7 , the side slider 23 includes a slider body 231. An inner conical surface 232 is provided at one end of the slider body 231. A self-healing component is provided on the outer wall of the inner conical surface 232. The self-healing component includes a porous structure 233, self-healing capsules 235 loaded inside the porous structure 233, and a wear-resistant layer 234 deposited on the outer wall of the porous structure 233.

[0059] Furthermore, the conical angle of the inner conical surface 232 is 5° - 10°, and it is adapted to the outer conical surface provided in the side sliding hole 224.

[0060] Specifically, the self-healing capsule 235 includes a core 2352 and a capsule wall 2351 wrapped outside the core 2352.

[0061] Furthermore, the preparation steps of the self-healing capsule 235 are as follows:

[0062] Core material dispersion: Disperse MoS2 nanosheets with a layer thickness < 10 nm in a PI precursor solution with a solid content of 15%;

[0063] Specifically, the number-average molecular weight of the PI precursor is 5000 - 15000 g / mol, and the dispersity is 1.1 - 1.6. If the molecular weight is too low, the mechanical strength of the capsule wall is insufficient, and the rupture stress < 0.5 MPa. If the molecular weight is too high, the viscosity > 500 cP, and emulsification is difficult; too large a dispersity results in uneven capsule wall thickness, and too small a dispersity may cause crystallization and embrittlement.

[0064] Atomization granulation: The inlet temperature is 180 °C, the outlet temperature is 80 °C, and capsules with a particle size distribution of 1 - 3 μm are formed;

[0065] Specifically, the PI wall thickness of the self-healing capsule 235 is 0.2 μm ± 0.01 μm, and the rupture stress strength is 15 MPa ± 0.1 MPa.

[0066] High-temperature curing: Heat-treat at 300 °C for 2 hours to crosslink and cure the capsule wall to obtain the self-healing capsule 235.

[0067] Further, the self-healing component is prepared through the following steps:

[0068] Laser processing of micropores: Using femtosecond laser with a wavelength of 1030 nm and a pulse energy of 50 μJ, the inner conical surface 232 is laser-treated for 30 - 50 femtoseconds to form a honeycomb microporous structure 233;

[0069] Vacuum impregnation: Under a vacuum of 10 -3 Pa, the inner conical surface 232 is immersed in the ethanol solvent of the self-healing capsule 235 suspension. Through capillary action, the self-healing capsule 235 is pressed into the porous structure 233, taken out, and dried to obtain an intermediate;

[0070] Specifically, the self-healing capsule 235 flows into the porous structure 233 through electrostatic adsorption and capillary action and is confined by the complex pores in the porous structure 233. After drying, the self-healing capsule 235 adheres to the inside of the porous structure 233.

[0071] Surface sealing: A wear-resistant layer 234 with a thickness of 5 - 10 nm and a composition of aluminum oxide is deposited on the surface of the intermediate through atomic layer deposition (ALD).

[0072] Specifically, by depositing an aluminum oxide film, the outside of the porous structure 233 with the self-healing capsule 235 attached is sealed. As the wear-resistant layer 234 wears, when some of the self-healing capsules 235 are ruptured by mechanical action, the released MoS2 nanosheets repair the inner conical surface 232, improving the accuracy of the inner conical surface 232 and extending the effective service life of the inner conical surface 232.

[0073] Please refer to Figure 8 , the secondary linkage mechanism 4 includes a hydraulic press 41 detachably installed in the installation groove 18, a linear bearing 42 installed in the placement hole 16, and a driving rod 43 partially extending into the adjustment channel 17. The hydraulic press 41 drives the driving rod 43 to expand and contract, pushing the side slider 23 to slide radially and applying radial pressure to the material.

[0074] It should be noted that the hydraulic press 41 can be disassembled and installed in the installation groove 18 through existing technologies such as riveting and fixing blocks, and the stability of the hydraulic press 41 after installation is ensured.

[0075] A forming process for high-voltage insulators using the above hot pressing device includes the following steps:

[0076] Loading: Place the lower slider 21 in the lower slide hole 225 and leave some margin. Add the insulator raw material into the mold cavity 223 from the upper slide hole 222, level it until the filling height is within the upper slide hole 222. Place several groups of side sliders 23 in the corresponding side slide holes 224 respectively, and then push the upper slider 24 along the upper slide hole 222 to compact it;

[0077] Mold installation: Place the loaded hot pressing mold 2 into the hot pressing cavity 13, and control the distance adjustment component 6 and the main linkage mechanism 3 to abut against the upper and lower ends of the hot pressing mold 2 respectively. Close the front box 11, and install the secondary linkage mechanism 4 into the installation groove 18, and make the driving rod 43 abut against the outer end of the side slider 23;

[0078] Program control: The secondary linkage mechanism 4 synchronously drives several groups of side sliders 23 to radially press into the light contact position, compacts the powder body and seals the mold cavity 223, and the pressure application range is 5 - 10 MPa; Heat to the target temperature, and at the same time, the main linkage mechanism 3 drives the downward sliding hole 225 to move upward to apply pressure to the raw material in the inner cavity of the mold cavity 223, and the pressure application range is 100 - 300 MPa; The secondary linkage mechanism 4 synchronously pressurizes the side sliders 23 to maintain the radial pressure, and the pressure application range is 20 - 90 MPa; During the heat preservation and pressure holding stage, the dynamic adjustment range of the pressure of the side sliders 23 is ±5 MPa;

[0079] Demolding: After the temperature drops to room temperature, control the four groups of side sliders 23 at the same horizontal height to synchronously retract by 0.3 - 0.5 mm through the secondary linkage mechanism 4, the two groups of diagonal side sliders 23 alternately retract by 2 mm each, and all the side sliders 23 synchronously retract until they are completely separated. The main linkage mechanism 3 controls to remove the pressure on the lower slider 21, open the front box 11, take out the hot pressing mold 2, remove each group of mold cores, open the mold sleeve, take out the hot pressed parts, and complete the hot pressing of the high - voltage insulator.

[0080] Principle: Place the lower slider 21 in the lower sliding hole 225 and leave some margin. Keep the side sliding hole 224 open. Add the insulator raw material into the mold cavity 223 from the upper sliding hole 222, and level it until the filling height is within the upper sliding hole 222. Place several groups of side sliders 23 into the corresponding side sliding holes 224 respectively. Then push the upper slider 24 along the upper sliding hole 222 to compact it, increasing the filling amount at the umbrella skirt position, thereby increasing the density of the complex structure part; Place the loaded hot pressing mold 2 into the hot pressing cavity 13, and control the distance adjusting component 6 and the main linkage mechanism 3 to abut against the upper and lower ends of the hot pressing mold 2 respectively. Close the front box body 11, and install the auxiliary linkage mechanism 4 into the installation groove 18, and make the driving rod 43 abut against the outer end of the side slider 23; The auxiliary linkage mechanism 4 synchronously drives several groups of side sliders 23 to radially press into the light contact position, compact the powder body and seal the mold cavity 223, heat it to the target temperature. At the same time, the main linkage mechanism 3 drives the lower sliding hole 225 to move upward to press the raw material inside the mold cavity 223, and the auxiliary linkage mechanism 4 synchronously pressurizes the side sliders 23 to maintain the radial pressure, and enters the heat preservation and pressure holding stage; After the temperature drops to room temperature, control the four groups of side sliders 23 at the same horizontal height to synchronously retreat 0.3 - 0.5 mm through the auxiliary linkage mechanism 4 to release the stress at the root of the umbrella skirt. The two diagonal side sliders 23 alternately retreat 2 mm each to prevent the umbrella skirt from deforming and interfering. All the side sliders 23 synchronously retreat until they are completely separated. The main linkage mechanism 3 controls to remove the pressure on the lower slider 21, open the front box body 11, take out the hot pressing mold 2, remove each group of mold cores, open the mold sleeve, and take out the hot pressing part to complete the hot pressing of the high-voltage insulator;

[0081] During the hot pressing process, the inner conical surface 232 frictions with the material and is subjected to the thermal expansion force of the material, and the wear-resistant layer 234 is worn. When the wear of the wear-resistant layer 234 reaches a certain degree, the porous structure 233 and the self-healing capsule 235 inside it are partially exposed. When the shear force on the self-healing capsule 235 is ≥ 15 MPa, the capsule wall 2351 ruptures, and the capsule core 2352 is released to repair the inner conical surface 232, improving the effective service life of the inner conical surface 232.

[0082] The above shows and describes the basic principle, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only the preferred examples of the present invention, and are not used to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A collaborative pressing structure, comprising a hot pressing die (2), characterized in that The hot pressing die (2) includes a die sleeve (22), an upper slider (24) and a lower slider (21) which are axially slidably connected to both ends of the die sleeve (22) respectively, and four groups of side sliders (23) which are circumferentially distributed on the side wall of the die sleeve (22) and are radially slidably connected to the die sleeve (22); The side slider (23) includes a slider body (231) and an inner conical surface (232) arranged at one end of the slider body (231). A self-healing component is arranged on the surface of the inner conical surface (232). The self-healing component includes a porous structure (233), a wear-resistant layer (234) and self-healing capsules (235) loaded in the porous structure (233). The conical angle of the inner conical surface (232) is 5°-10°.

2. The co-pressurizing structure according to claim 1, characterized in that The die sleeve (22) includes a die sleeve body (221). A die cavity (223) is formed inside the die sleeve body (221). Upper sliding holes (222) and lower sliding holes (225) communicating with the outside are respectively formed at the top and bottom of the die cavity (223). Four groups of side sliding holes (224) are circumferentially formed in the umbrella skirt distribution section of the die cavity (223). An outer conical surface adapted to the inner conical surface (232) is formed at one end of the side sliding hole (224) communicating with the die cavity (223).

3. A self-healing hot pressing device, characterized in that, It includes the cooperative pressing structure according to any one of claims 1-2, and further includes: A frame (5) and a control mechanism; A device main body (1) installed in the inner cavity of the frame (5). The device main body (1) includes a rear box body (15) arranged at the top of the inner cavity of the frame (5), a front box body (11) hinged to the side surface of the rear box body (15), and a heating, heat preservation and heat dissipation mechanism; Four groups of auxiliary linkage mechanisms (4) installed around the device main body (1). The auxiliary linkage mechanisms (4) are electrically connected to the control mechanism and are used to drive the side sliders (23) to perform linear reciprocating motion along the radial direction of the die sleeve (22); A main linkage mechanism (3) installed at the bottom of the inner cavity of the frame (5). The main linkage mechanism (3) is electrically connected to the control mechanism and is used to drive the lower slider (21) to perform linear reciprocating motion along the axial direction of the die sleeve (22); An adjustable distance component (6) installed at the top of the frame (5), which is used to drive the upper slider (24) to perform linear reciprocating motion along the axial direction of the die sleeve (22).

4. The self-healing hot pressing device according to claim 3, characterized in that, A hot pressing cavity (13) is formed in the middle of the front box body (11) and the rear box body (15). When the front box body (11) and the rear box body (15) are closed, installation grooves (18) are formed at the same horizontal height in the middle of the periphery of the device main body (1). An installation hole (16) is formed at the bottom of the installation groove (18) along the radial direction. An adjustment channel (17) communicating with the hot pressing cavity (13) is formed at the bottom of the installation hole (16).

5. The self-healing hot pressing device according to claim 3, wherein, The self-healing component is prepared by the following steps: Laser processing of micropores: The surface of the inner conical surface (232) is processed by femtosecond laser with a wavelength of 1030 nm and a pulse energy of 50 μJ to form a honeycomb-like microporous structure (233); Vacuum impregnation: Under a vacuum of 10 -3 Pa, immerse the inner conical surface (232) in a suspension (ethanol solvent) of self-healing capsules (235), and press the self-healing capsules (235) into the porous structure (233) through capillary action, take out and dry to obtain an intermediate product; Surface sealing: A wear-resistant layer (234) is deposited on the surface of the intermediate body by atomic layer deposition; Among them, the wear-resistant layer (234) is more preferably an aluminum oxide film with a thickness of 5-10 nm.

6. The collaborative pressure structure and self-healing hot pressing device according to claim 5, characterized in that, The self-healing capsule (235) is prepared by the following steps: Core material dispersion: The core material is dispersed in the PI precursor solution with a solid content of 15%. Atomization granulation: The inlet temperature is 180°C and the outlet temperature is 80°C to form capsules with a particle size distribution of 1 - 3 μm. High-temperature curing: Heat treatment is carried out at 300°C for 2 hours to crosslink and cure the capsule wall to obtain the self-healing capsule (235). Among them, the number-average molecular weight of the PI precursor is 5000 - 15000 g / mol, the dispersity is 1.1 - 1.6, the PI wall thickness of the self-healing capsule (235) is 0.2 μm ± 0.1 μm, and the mechanical stress response strength is 15 MPa ± 0.1 MPa.

7. The self-healing hot pressing device according to claim 6, wherein The self-healing capsule (235) includes a capsule wall (2351) and a core (2352) wrapped inside the capsule wall (2351).

8. The self-healing hot pressing device according to claim 7, wherein, The core (2352) is more preferably a MoS2 nanosheet with a layer thickness of < 10 nm.

9. The self-healing hot pressing device according to claim 3, characterized in that, The secondary linkage mechanism (4) includes a hydraulic press (41) detachably connected in the installation groove (18), a linear bearing (42) installed in the installation hole (16), and a driving rod (43) partially extending into the adjustment channel (17). The hydraulic press (41) drives the driving rod (43) to perform reciprocating linear motion.

10. A high-voltage insulator forming process, characterized in that, Using the hot pressing device according to any one of claims 3 - 9, it includes the following steps: Loading: Place the lower slider in the lower sliding hole and leave some margin. Keep the side sliding holes open. Add insulator raw materials into the mold cavity from the upper sliding hole, level it until the filling height is within the upper sliding hole. Place several groups of side sliders in the corresponding side sliding holes respectively, and then push the upper slider along the upper sliding hole to compact it. Mold installation: Place the loaded hot pressing mold in the hot pressing cavity, control the distance adjustment component and the main linkage mechanism to abut against the upper and lower ends of the hot pressing mold respectively, close the front box body, and install the secondary linkage mechanism in the installation groove, and make the driving rod abut against the outer end of the side slider. Program control: The secondary linkage mechanism synchronously drives several groups of side sliders to radially press into the light contact position, compact the powder body and seal the mold cavity, with a pressure application range of 5 - 10 MPa; heat to the target temperature, and at the same time, the main linkage mechanism drives the lower sliding hole to move upward to apply pressure to the raw materials inside the mold cavity, with a pressure application range of 100 - 300 MPa; the secondary linkage mechanism synchronously pressurizes the side sliders to maintain the radial pressure, with a pressure application range of 20 - 90 MPa; during the heat preservation and pressure holding stage, the dynamic adjustment range of the side slider pressure is ±5 MPa. Demolding: After the temperature drops to room temperature, control the four groups of side sliders at the same horizontal height to retreat synchronously by 0.3 - 0.5 mm through the secondary linkage mechanism, the two diagonal groups of side sliders retreat alternately by 2 mm each, and all side sliders retreat synchronously until completely separated. The main linkage mechanism controls the removal of the pressure on the lower slider, opens the front box body, takes out the hot pressing mold, removes each group of mold cores, opens the mold sleeve, and takes out the hot pressed part to complete the hot pressing of the high-voltage insulator.

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