A high thermal conductivity isostatic graphite preparation system and preparation method

Abstract

The present invention provides a high thermal conductivity isostatic pressing graphite preparation system and a preparation method, which relates to the technical field of presses. The preparation system includes a feeding device and an isostatic press. The isostatic press includes a high-pressure vessel, and the high-pressure vessel is divided into multiple chambers from top to bottom. The chambers are cuboid-shaped, and a pressurizing and pressure-relieving system for controlling the pressure rise and fall is provided on the side of the chamber. A plug plate is slidably arranged between two adjacent chambers up and down, and a pressure equalizing pipe is connected between two adjacent chambers up and down. A valve, a buffer component and a throttling component are provided on the pressure equalizing pipe. The preparation method includes: crushing and grinding raw materials to obtain powder; loading the powder into an elastic mold and sealing it; putting the elastic mold into the isostatic press for isostatic pressing; subjecting the formed material to primary roasting, impregnation, secondary roasting, graphitization and cooling in sequence to obtain isostatic pressing graphite; spraying and curing graphene coating after cleaning and drying the graphite. The present invention improves the production efficiency of isostatic pressing graphite by improving the working efficiency of the isostatic press.

Description

Technical Field

[0001] The present invention relates to the technical field of presses, and particularly to a high thermal conductivity isostatic graphite preparation system and a preparation method thereof. Background Art

[0002] Isostatic graphite refers to special graphite formed by isostatic pressing technology. It not only has great applications in civilian use but also occupies an important position in national defense. It is a new type of material that has attracted much attention. It is also an irreplaceable material for manufacturing single crystal furnaces, graphite crystallizers for continuous metal casting, graphite electrodes for electric discharge machining, etc. It is an excellent material for manufacturing rocket nozzles, deceleration materials and reflector materials for graphite reactors.

[0003] In the prior art, when an isostatic press presses graphite, due to the long loading and unloading time, the isostatic press cannot operate during this process, resulting in less effective working hours of the equipment. Moreover, the time for pressurizing after the graphite is loaded into the isostatic press and the time for depressurizing before the isostatic press removes the graphite are both long, further leading to low working efficiency of the isostatic press and affecting the production efficiency of isostatic graphite. Summary of the Invention

[0004] The purpose of the present invention is to develop a high thermal conductivity isostatic graphite preparation system and a preparation method thereof that improve the production efficiency of isostatic graphite by increasing the working efficiency of the isostatic press.

[0005] The present invention is achieved through the following technical solutions:

[0006] A high thermal conductivity isostatic graphite preparation system, comprising:

[0007] A feeding device and an isostatic press. The feeding device feeds the elastic mold of the isostatic press. The feeding device includes a feeding mechanism, a pressing mechanism and a capping mechanism;

[0008] Among them, the feeding mechanism includes a support. A universal ball that can roll freely is movably arranged on the support. A driving component for driving the universal ball to rotate is arranged inside the support. A feeding pipe penetrates through the universal ball. A vibrating rod is connected to the bottom of the universal ball;

[0009] The pressing mechanism includes a pressing plate. A vacuum pipe communicated with a vacuum system is arranged on the top of the pressing plate. A second vibration component is arranged at the bottom of the pressing plate;

[0010] The capping mechanism includes a pipe rack. A plurality of support pipes are rotatably arranged on the pipe rack. The top ends of the support pipes are communicated with suction nozzles. A vacuum hose communicated with the support pipes is arranged on the pipe rack. The vacuum hose is communicated with the vacuum system;

[0011] The isostatic press includes a high-pressure vessel, which is divided into multiple chambers from top to bottom. The chambers are cuboid-shaped. A pressurizing and depressurizing system for controlling the pressure rise and fall is provided on the side of the chamber. A plug plate is slidably provided between two adjacent chambers up and down. A pressure equalizing pipe is connected between two adjacent chambers up and down. A valve, a buffer component and a throttling component are provided on the pressure equalizing pipe.

[0012] Optionally, an upper pressure cover is provided on the top of the high-pressure vessel, a side chamber is provided at the bottom of the high-pressure vessel, the side chamber is communicated with the bottommost chamber, and a lower pressure cover is provided on the top of the side chamber;

[0013] A plate shell for accommodating the plug plate to slide in and out is provided on the high-pressure vessel outside the plug plate. A hydraulic cylinder for driving the plug plate to slide is correspondingly provided on the plate shell. A plate groove for sliding and sealing the edge of the plug plate is correspondingly provided on the inner wall of the high-pressure vessel;

[0014] A push plate arranged vertically is provided in the bottommost chamber. A hydraulic cylinder for driving the push plate to slide is provided outside the high-pressure vessel on the side of the push plate.

[0015] Optionally, the vibrating rod is arranged parallel to the feed pipe, and the vibrating rod head provided at the end of the vibrating rod is lower than the end of the feed pipe;

[0016] The driving assembly includes a driving ring arranged outside the universal ball. The driving ring is horizontally rotatably arranged in the support. The inner wall of the driving ring is in rolling contact with the outer wall of the universal ball. An outer ring gear is provided on the outer ring wall of the driving ring. A motor and a gear in transmission connection are correspondingly provided in the support. The gear meshes with the outer ring gear. A driving groove is vertically opened on the outer wall of the universal ball. An arc-shaped rack with a corresponding shape is provided in the driving groove. A driving gear meshing with the rack is provided in the driving groove. The driving gear is rotatably arranged on the driving ring. A micro-motor in transmission connection with the driving gear is correspondingly provided on the driving ring.

[0017] Optionally, the shape of the pressing plate is adapted to the inner cavity of the elastic mold. A sealing ring made of an elastic material is provided on the edge of the pressing plate. The pipe orifice of the vacuum pipe extends to the bottom of the pressing plate. The second vibration assembly at the pipe orifice of the vacuum pipe corresponds to an opening. A filtering structure for preventing materials from being sucked in is provided in the pipe orifice of the vacuum pipe at the bottom of the pressing plate.

[0018] Optionally, the pressing cover mechanism further includes a suction cup. The shape of the pipe rack is the same as the outer wall shape of the elastic mold and has a larger size. A plurality of support pipes are arranged on the pipe rack at equal intervals. The bottom end of the support pipe is rotatably connected to the pipe rack. A micro-motor for driving the support pipe to swing is provided on the pipe rack. A filtering structure for preventing materials from being sucked in is provided in the suction nozzle.

[0019] A preparation method of a high thermal conductivity isostatic pressing graphite preparation system includes the following steps:

[0020] S1. Crush and grind the raw materials, then knead them, and then crush and grind them for the second time to obtain powder materials.

[0021] S2. Feed the powder materials into the elastic mold in multiple times from bottom to top through the feeding mechanism, and compact the powder materials in the elastic mold through the pressing mechanism after each loading.

[0022] S3. Cover the top cover on the elastic mold through the capping mechanism, and then bind the top cover and the elastic mold to achieve sealing.

[0023] S4. Place the elastic mold in an isostatic press for isostatic pressing.

[0024] S5. Take out the elastic mold and the formed material, and then carry out primary roasting, impregnation, secondary roasting, graphitization, and cooling in sequence to obtain isostatic graphite.

[0025] S6. Clean and dry the isostatic graphite.

[0026] S7. Spray and cure the graphene coating on the graphite surface to obtain high - thermal - conductivity isostatic graphite.

[0027] Among them, the elastic mold is placed into the isostatic press from the top, and the elastic mold passes through multiple chambers from top to bottom in the isostatic press.

[0028] The chambers inside the isostatic press have working pressure and conveying pressure. The working pressure is the pressure when the chamber is airtight, and the conveying pressure is the pressure for the transfer of the elastic mold when the chamber is connected to the adjacent chamber. The multiple chambers are A1, A2... Am... An - 1, An from top to bottom. Among them, A1 is at the top, An is at the bottom. The internal working pressure from A1 to Am gradually increases, the internal working pressure from Am to An gradually decreases, the working pressure of Am is the largest, and the material is isostatically pressed in Am. The working pressures of A1 and An are normal pressure. Under the working pressure, A1 and An can be opened to put in or take out the elastic mold.

[0029] Optionally, when the elastic mold moves downward in the isostatic press, the elastic mold in the bottom - most chamber is moved out of the isostatic press, then the plug plate at the top of the bottom - most chamber is opened to make the elastic mold in the upper chamber fall into the bottom - most chamber, then the plug plate at the top of the bottom - most chamber is closed, and the chambers above the bottom - most chamber repeat the above process in sequence, so that the elastic molds in each chamber gradually descend into the lower chamber. After the elastic mold in the top - most chamber moves downward, a new elastic mold filled with materials is put in.

[0030] When the elastic mold is transferred between the two adjacent chambers, the valve of the pressure equalizing pipe between the two chambers is opened, the two chambers are connected and pressure-equalized, the plug plate between the two chambers is opened, the elastic modulus falls into the lower chamber, the valve of the pressure equalizing pipe is closed, the plug plate is closed, the two chambers are sealed, and then the pressure in the chamber reaches the working pressure through the boosting or pressure relief system.

[0031] Optionally, in step S2, the process of each loading of the feeding mechanism includes: the feeding pipe and the vibrating rod are extended into the elastic mold, the feeding pipe is fed, and the vibrating rod is vibrated. At the same time, the end of the feeding pipe starts from the inner wall of the elastic mold, and performs multiple circular movements from the outside to the inside step by step. The trajectory of the circular movement is adapted to the internal shape of the elastic mold, and the trajectories of the multiple circular movements gradually shrink from the outside to the inside. The coverage area of the multiple circular movements covers the cross-section of the elastic mold. Each circular movement is repeated at least twice. After the loading is completed, the feeding mechanism withdraws the elastic mold, and the pressing mechanism compacts the material in the elastic mold before the next loading. The loading and pressing are performed alternately until the elastic mold is filled with material.

[0032] Optionally, in step S2, when the pressing mechanism is pressing the material, the pressing plate enters the elastic mold and descends to compact the material. During this process, the second vibration component vibrates, and the vacuum tube is evacuated to exhaust the air in the material and compact the material. After the pressing is completed, the pressing plate is withdrawn from the elastic mold.

[0033] Optionally, in step S3, the tube rack of the capping mechanism is located below the top cover, and the support tube on the tube rack swings inward at a certain angle and enters the inner side of the top cover side wall from the bottom of the top cover, and multiple support tubes open the bottom of the top cover so that the opening of the top cover gradually increases from top to bottom, and the top cover enters the opening of the elastic mold along the tube rack, and the top cover is pressed into the opening of the elastic mold until the top of the top cover covers the elastic mold. During this process, the suction nozzle performs vacuum extraction to discharge the air on the upper part of the elastic mold. After the top of the top cover covers the elastic mold, the tube rack starts to descend, and the suction nozzle still maintains vacuum extraction during the descent. After the support tube and the suction nozzle descend, the side wall of the top cover is tightly attached to the top side wall of the elastic mold. After the suction nozzle and the support tube descend and completely detach from the top cover, the top cover is tightly attached to the elastic mold due to its elasticity, and the tube rack rises and evacuates from the outside of the elastic mold.

[0034] The beneficial effects of the present invention are:

[0035] When the isostatic press is loaded at the top and discharged at the bottom, the graphite is continuously pressed inside. The loading and discharging behavior does not hinder the pressing of graphite, which improves the working efficiency of the isostatic press and the production efficiency of isostatic graphite.

[0036] The pressure inside the isostatic press chamber gradually increases and then gradually decreases. The pressure difference between adjacent chambers is relatively small, so the unidirectional pressure on the partition plate between adjacent chambers is also relatively small. The pressure resistance requirement for the partition plate is relatively low, and the structural life and sealing effect are extended.

[0037] Each chamber maintains a certain pressure, with a relatively small range of pressure increase and decrease. The working load of the pressure increase and pressure relief systems is low, resulting in increased service life and reduced failure rate. The time taken for pressure increase and pressure relief is also relatively short, so the waiting time for graphite during pressure increase and pressure relief is short, and the production efficiency of graphite is improved. Moreover, the pressure in multiple chambers gradually increases and decreases, enabling the graphite to be uniformly pressed and deformed, which helps to obtain graphite with a fine, dense, and uniform structure.

[0038] When filling, compacting, and capping the material in the elastic mold, it is carried out through the feeding mechanism, pressing mechanism, and capping mechanism. This not only improves the operation efficiency, shortens the filling time of the elastic mold, and increases the production efficiency of isostatic graphite, but also ensures the consistency of equipment filling. The degree of compaction uniformity of the filling can be controlled and is not affected by factors such as manual operation skills and experience.

[0039] When the feeding mechanism feeds material into the elastic mold, it makes multiple circular motions for filling and vibrating, ensuring that the material is evenly filled in the elastic mold without voids. The material is filled in multiple times, and after each filling, the pressing mechanism compresses and evacuates the filled material, further improving the compactness of the material in the elastic mold. After the material is filled, the capping mechanism automatically covers the top cover on the elastic mold, and during this process, vacuum is applied to further improve the compactness of the material in the elastic mold and the sealing performance between the top cover and the elastic mold.

[0040] The graphene coating applied to the outside of isostatic graphite not only improves the durability, corrosion resistance, etc. of graphite as a protective structure but also enhances the thermal conductivity of graphite. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0042] Figure 1 It is a schematic structural diagram of the feeding device;

[0043] Figure 2 It is a schematic structural diagram of the driving component;

[0044] Figure 3 For Figure 2 top view;

[0045] Figure 4 It is a schematic structural diagram of the blank holding mechanism;

[0046] Figure 5 It is a schematic structural diagram of the gland pressing mechanism;

[0047] Figure 6 It is a schematic structural diagram of the isostatic press.

[0048] Reference numerals: 100, feeding device; 110, feeding seat; 120, first vibration assembly; 130, feeding mechanism; 131, support; 132, universal ball; 133, feeding pipe; 134, vibrating rod; 135, driving groove; 136, rack; 137, driving gear; 138, driving ring; 140, blank holding mechanism; 141, pressing plate; 142, vacuum pipe; 143, second vibration assembly; 150, gland pressing mechanism; 151, suction cup; 152, pipe support; 153, support pipe; 154, suction nozzle; 200, isostatic press; 210, elastic mold; 211, top cover; 220, metal sleeve; 230, high-pressure vessel; 231, chamber; 232, upper gland; 233, lower gland; 234, side chamber; 240, insertion plate; 250, pressure equalizing pipe; 260, push plate. Detailed implementation manners

[0049] In the following, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present invention. Therefore, the drawings and the description are considered to be exemplary in nature and not restrictive.

[0050] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0051] The embodiments of the present invention will be described in detail below with reference to the drawings.

[0052] Such as Figures 1 to 6As shown in the figure, the present invention discloses a high thermal conductivity isostatic pressing graphite preparation system, which includes a feeding device 100 and an isostatic press 200. The feeding device 100 includes a feeding base 110, on which a seat groove is provided. At the bottom of the seat groove, a first vibration assembly 120 is provided, and an elastic layer is provided on the inner wall of the seat groove. The seat groove accommodates the perforated metal sleeve 220 of the isostatic press 200, and an elastic mold 210 is arranged inside the metal sleeve 220.

[0053] The elastic layer is an elastic air cushion made of rubber material. The first vibration assembly 120 includes an elastic cushion layer provided on the bottom surface of the seat groove. A plurality of ultrasonic transducers are provided at the bottom of the elastic cushion layer, and the ultrasonic transducers are electrically connected to an ultrasonic generator. The metal sleeve 220 is placed on the elastic cushion layer. The high-frequency oscillation signal emitted by the ultrasonic generator is converted into a high-frequency mechanical oscillation through the ultrasonic transducers, causing the metal sleeve 220 to vibrate. The elastic layer and the elastic cushion layer prevent the metal sleeve 220 from rigidly contacting the inside of the feeding base 110.

[0054] Above the feeding base 110, a feeding mechanism 130, a material pressing mechanism 140 and a cover pressing mechanism 150 are provided. The feeding mechanism 130 fills the material into the elastic mold 210, the material pressing mechanism 140 compresses the material in the elastic mold 210, and the cover pressing mechanism 150 installs the top cover 211 of the elastic mold 210.

[0055] The feeding mechanism 130 includes a support 131 that can move in three directions. A universal ball 132 that can roll arbitrarily is movably provided on the support 131. A part of the universal ball 132 is exposed at the top and bottom of the support 131. Corresponding ball grooves for accommodating the universal ball 132 and rolling contact with it are provided inside the support 131, and the support 131 holds the universal ball 132 through the ball grooves.

[0056] A feeding pipe 133 is provided on the universal ball 132. The feeding pipe 133 penetrates through the universal ball 132. A vibrating rod 134 is provided on the universal ball 132 at the lower part of the support 131. The vibrating rod 134 is arranged parallel to the feeding pipe 133. A vibrating rod head is provided at the end of the vibrating rod 134, and the vibrating rod head is lower than the end of the feeding pipe 133.

[0057] The support 131 is provided with a driving assembly for driving the universal ball 132 to rotate. The driving assembly includes a driving ring 138 arranged outside the universal ball 132. The driving ring 138 is horizontally rotatably arranged in the support 131. The inner wall of the driving ring 138 is in rolling contact with the outer wall of the universal ball 132. An outer ring gear is arranged on the outer ring wall of the driving ring 138. A motor and a gear in transmission connection are arranged at the corresponding position in the support 131. The gear meshes with the outer ring gear. Vertically arranged driving grooves 135 are formed in the outer wall of the universal ball 132. Arc-shaped racks 136 with corresponding shapes are arranged in the driving grooves 135. Driving gears 137 meshing with the racks 136 are arranged in the driving grooves 135. The driving gears 137 are rotatably arranged on the driving ring 138. Micromotors in transmission connection with the driving gears 137 are arranged at the corresponding positions on the driving ring 138. Since the driving gears 137 are located in the driving grooves 135 and mesh with the racks 136, when the driving ring 138 rotates horizontally, the driving gears 137 will push the driving grooves 135 to drive the universal ball 132 to rotate horizontally synchronously. The micromotors drive the driving gears 137 to rotate, and the driving gears 137 drive the racks 136 to enable the universal ball 132 to rotate vertically in the driving ring 138.

[0058] When the feeding mechanism 130 feeds materials, the universal ball 132 is positioned above the elastic mold 210 and the two are coaxially arranged. The feeding pipe 133 and the vibrating rod 134 are inserted into the elastic mold 210. When the feeding pipe 133 feeds materials, the rotation of the universal ball 132 drives the feeding pipe 133 to rotate in the elastic mold 210, so that the materials output by the feeding pipe 133 fall into the elastic mold 210 along a circular trajectory. The universal ball 132 can rotate in the vertical direction to adjust the angle, so that the diameter of the circular trajectory of the outlet of the feeding pipe 133 increases or decreases and the circular trajectory remains coaxially arranged with the elastic mold 210. By making the outlet of the feeding pipe 133 draw circles multiple times and changing the diameter of the drawn circles, the materials output by the feeding pipe 133 can evenly fill the elastic mold 210. During this process, the vibrating rod head at the end of the vibrating rod 134 vibrates the output materials so that the materials are filled without large voids. During the process of the rotation of the universal ball 132 driving the movement of the feeding pipe 133, by controlling the rotation angle of the universal ball 132 in the vertical direction to control the inclination angle of the feeding pipe 133, thereby controlling the distance between the outlet of the feeding pipe 133 and the axis of the universal ball 132, the projection of the trajectory of the swing of the outlet of the feeding pipe 133 in the horizontal plane can be in the shape of a rectangle to adapt to the cuboid-shaped elastic mold 210.

[0059] The blank holding mechanism 140 includes a pressure plate 141 that can move in three directions. The shape of the pressure plate 141 is adapted to the inner cavity of the elastic mold 210. A sealing ring made of elastic material is provided at the edge of the pressure plate 141. A second vibration assembly 143 having the same structure as the first vibration assembly 120 is provided at the bottom of the pressure plate 141. A vacuum tube 142 is provided at the top of the pressure plate 141. The pipe orifice of the vacuum tube 142 extends to the bottom of the pressure plate 141, and the second vibration assembly 143 at the pipe orifice corresponds to an opening. The vacuum tube 142 is connected to a vacuum system. A filtering structure to prevent the material from being sucked in is provided inside the pipe orifice of the vacuum tube 142 at the bottom of the pressure plate 141.

[0060] When the blank holding mechanism 140 performs blank holding, after the pressure plate 141 and the elastic mold 210 are in a coaxial state, it descends into the elastic mold 210. The pressure plate 141 presses the material in the elastic mold 210. During this process, the second vibration assembly 143 vibrates, and the vacuum tube 142 evacuates the air, so that the material is pressed and the air in the material is extracted to improve the compaction degree. After the material is compacted, the pressure plate 141 rises and disengages from the elastic mold 210.

[0061] The capping mechanism 150 includes a three-way moving suction cup 151 and a three-way moving pipe rack 152. The suction cup 151 is used to suck and transport the top cover 211 of the elastic mold 210. The shape of the pipe rack 152 is the same as the outer wall shape of the elastic mold 210 and has a larger size, so that the pipe rack 152 can be lifted and lowered freely outside the elastic mold 210. A plurality of support pipes 153 are arranged at equal intervals on the pipe rack 152. The bottom ends of the support pipes 153 are rotatably connected to the pipe rack 152. A micro motor for driving the support pipes 153 to swing is provided on the pipe rack 152. The top ends of the support pipes 153 are connected to suction nozzles 154. A filtering structure to prevent the material from being sucked in is also provided inside the suction nozzles 154. Vacuum hoses corresponding to the support pipes 153 are provided on the pipe rack 152 and are connected to the vacuum system.

[0062] After the suction cup 151 holds the top cover 211, the pipe rack 152 enters below the top cover 211, and multiple support pipes 153 all incline inward. If the top cover 211 is a circular cover, the multiple support pipes 153 form a frustum of a cone shape after inclining inward, and the diameter of the top of the frustum of the cone is adapted to the inner diameter of the top cover 211. If the top cover 211 is a rectangular cover, the multiple support pipes 153 form a frustum of a pyramid shape after inclining inward, and the rectangle at the top of the frustum of the pyramid is adapted to the multiple inner tops. After the multiple support pipes 153 incline inward, the pipe rack 152 rises, so that the tops of the multiple support pipes 153 are inserted upward from the inner wall at the bottom of the top cover 211 to the inner top of the top cover 211. The multiple support pipes 153 expand the side wall of the top cover 211. At this time, the size of the side wall of the top cover 211 gradually increases from top to bottom, which is convenient for the top cover 211 to cover on the elastic mold 210. The suction cup 151 and the pipe rack 152 move synchronously to cover the top cover 211 on the top of the elastic mold 210. During this process, the suction nozzle 154 sucks, sucking away the air between the top cover 211 and the top of the elastic mold 210, reducing the air residue inside the elastic mold 210. After the top cover 211 covers on the elastic mold 210, the suction cup 151 is fixed, and the pipe rack 152 descends to drive the multiple support pipes 153 to descend. During the descent of the support pipes 153, the suction nozzle 154 keeps sucking. The side wall of the top cover 211 that is separated from the top of the support pipe 153 resets elastically and closely adheres to the side wall at the top of the elastic mold 210. The suction nozzle 154 sucks the air between them, so that the air between the side wall of the top cover 211 and the side wall at the top of the elastic mold 210 is sucked away, and the two can be closely adhered and sealed. After the support pipes 153 completely descend and are separated from the top cover 211, the support pipes 153 swing to the vertical state to achieve reset, and the pipe rack 152 rises and separates from the outside of the elastic mold 210.

[0063] The isostatic press 200 includes a high-pressure container 230. Inside the high-pressure container 230, it is divided into multiple chambers 231 from top to bottom. The chambers 231 are in the shape of a cuboid. The internal pressure of the multiple chambers 231 gradually increases and then gradually decreases from top to bottom. A pressurizing and pressure-relieving system for controlling the pressure rise and fall is provided on the side of each chamber 231. A top pressure cover 232 is provided at the top of the high-pressure container 230, and the top pressure cover 232 is also at the top of the topmost chamber 231. A side chamber 234 is provided at the bottom of the high-pressure container 230. The side chamber 234 is communicated with the bottommost chamber 231, and a bottom pressure cover 233 is provided at the top of the side chamber 234.

[0064] A sliding plate 240 that can slide horizontally is provided between two adjacent upper and lower chambers 231. On the high-pressure container 230 outside the sliding plate 240, there is a plate housing for the sliding plate 240 to slide in and out. A hydraulic cylinder for driving the sliding plate 240 to slide is correspondingly provided on the plate housing. A plate groove for sliding and sealing the edge of the sliding plate 240 is correspondingly provided on the inner wall of the high-pressure container 230. The hydraulic cylinder drives the sliding plate 240 to slide into the high-pressure container 230 from the plate housing, which can seal the two chambers 231 above and below the sliding plate 240. The hydraulic cylinder drives the sliding plate 240 to slide into the plate housing, which can communicate the two upper and lower chambers 231.

[0065] A pressure equalizing pipe 250 is connected between two vertically adjacent chambers 231. A valve, a buffer component and a throttling component are provided on the pressure equalizing pipe 250.

[0066] A push plate 260 arranged vertically is provided in the lowermost chamber 231. A hydraulic cylinder for driving the push plate 260 to slide is provided outside the high-pressure container 230 on the side of the push plate 260. The hydraulic cylinder drives the push plate 260 to slide towards the side chamber 234, and the push plate 260 can push the elastic mold 210 into the side chamber 234.

[0067] The present invention also discloses a preparation method of the above high thermal conductivity isostatic pressing graphite preparation system, including the following steps:

[0068] S1. Crushing and grinding the raw materials, then kneading, and then performing secondary crushing and grinding to obtain powder materials;

[0069] S2. Loading the powder materials into the elastic mold 210 in multiple times from bottom to top through the feeding mechanism 130, and compacting the powder materials in the elastic mold 210 through the pressing mechanism 140 after each loading;

[0070] S3. Covering the top cover 211 on the elastic mold 210 through the capping mechanism 150, and then bundling the top cover 211 and the elastic mold 210 to achieve sealing;

[0071] S4. Placing the elastic mold 210 into the isostatic press 200 for isostatic pressing;

[0072] S5. Taking out the elastic mold 210 and taking out the formed material, and then performing primary roasting, impregnation, secondary roasting, graphitization, and cooling in sequence to obtain isostatic pressing graphite;

[0073] S6. Cleaning and drying the isostatic pressing graphite;

[0074] S7. Spraying and curing a graphene coating on the surface of the graphite to obtain high thermal conductivity isostatic pressing graphite;

[0075] Wherein, in step S2, the elastic mold 210 is placed in the perforated metal sleeve 220, the metal sleeve 220 is placed in the seat groove of the feeding seat 110, and the first vibration assembly 120 at the bottom of the seat groove vibrates to keep the metal sleeve 220 and the elastic mold 210 vibrating during the loading process. In step S3, after the top cover 211 and the elastic mold 210 are bundled, the cover of the metal sleeve 220 is covered and fixed;

[0076] In step S2, the process of each loading by the feeding mechanism 130 includes: the feeding pipe 133 and the vibrating rod 134 extend into the elastic mold 210. The feeding pipe 133 feeds materials, and the vibrating rod 134 vibrates. At the same time, the end of the feeding pipe 133 starts from the inner side wall of the elastic mold 210 and performs multiple circular motions step by step from the outside to the inside. The trajectory of the circular motion fits the internal shape of the elastic mold 210. The trajectories of the multiple circular motions gradually shrink from the outside to the inside. The covering area of the multiple circular motions covers most or the entire cross-section of the elastic mold 210. Each circular motion is repeated at least twice. After the loading is completed, the feeding mechanism 130 withdraws from the elastic mold 210. The pressing mechanism 140 compacts the materials in the elastic mold 210 and then performs the next loading. Loading and pressing are alternately performed until the elastic mold 210 is filled with materials;

[0077] In step S2, when the pressing mechanism 140 performs pressing, the pressing plate 141 enters the elastic mold 210 and descends to compact the materials. During this process, the second vibration assembly 143 generates vibration, and the vacuum tube 142 evacuates the air, discharging the air in the materials and compacting the materials. After the pressing is completed, the pressing plate 141 withdraws from the elastic mold 210;

[0078] In step S3, the pipe rack 152 of the capping mechanism 150 is located below the top cover 211. The supporting pipes 153 on the pipe rack 152 swing inward by a certain angle and then enter the inner side of the side wall of the top cover 211 from the bottom of the top cover 211. The multiple supporting pipes 153 expand the bottom of the top cover 211, making the opening of the top cover 211 gradually increase from top to bottom. The top cover 211 enters the opening of the elastic mold 210 along with the pipe rack 152, and the top cover 211 is pressed into the opening of the elastic mold 210 until the top of the top cover 211 covers the elastic mold 210. During this process, the suction nozzle 154 evacuates the air, trying to discharge the air in the upper part of the elastic mold 210 as much as possible, so that while the top cover 211 is tightly covered on the elastic mold 210, the air remaining between the top cover 211 and the elastic mold 210 is reduced. After the top of the top cover 211 covers the elastic mold 210, the pipe rack 152 starts to descend. During the descending process, the suction nozzle 154 still maintains evacuation. After the supporting pipes 153 and the suction nozzle 154 descend and completely separate from the top cover 211, the elasticity of the top cover 211 makes its side wall closely adhere to the top side wall of the elastic mold 210. The suction of the suction nozzle 154 reduces the air between the two, making the two closely adhere to achieve sealing. After the suction nozzle 154 and the supporting pipes 153 completely descend and separate from the top cover 211, the top cover 211 tightly adheres to the elastic mold 210 due to its elasticity, and the pipe rack 152 rises and withdraws from the outside of the elastic mold 210;

[0079] The flexible mold 210 is placed into the top of the isostatic press 200. The flexible mold 210 passes through multiple chambers 231 from top to bottom within the isostatic press 200. When the flexible mold 210 moves downward within the isostatic press 200, the flexible mold 210 in the lowermost chamber 231 is removed from the isostatic press 200. Then, the plug plate 240 at the top of the lowermost chamber 231 is opened to allow the flexible mold 210 in the upper chamber 231 to fall into the lowermost chamber 231. Subsequently, the plug plate 240 at the top of the lowermost chamber 231 is closed. The chambers 231 above the lowermost chamber 231 repeat the above process in sequence, enabling the flexible mold 210 in each chamber 231 to descend one by one into the lower chamber 231. After the flexible mold 210 in the uppermost chamber 231 moves downward, a new flexible mold 210 filled with materials is placed in;

[0080] The chambers 231 inside the isostatic press 200 have a working pressure and a conveying pressure. The working pressure is the pressure when the chamber 231 is sealed, and the conveying pressure is the pressure for the transfer of the flexible mold 210 when the chamber 231 is in communication with the adjacent chamber 231. The multiple chambers 231 are respectively A1, A2... Am... An-1, An from top to bottom. Among them, A1 is at the top and An is at the bottom. The internal working pressure from A1 to Am gradually increases, and the internal working pressure from Am to An gradually decreases. The working pressure of Am is the highest, and the materials are mainly isostatically formed in Am. The working pressures of A1 and An are normal pressures. Under the working pressure, A1 and An can be opened to place or remove the flexible mold 210;

[0081] When the flexible mold 210 is transferred between two adjacent upper and lower chambers 231, the valve of the pressure equalizing pipe 250 between the two chambers 231 is opened, the two chambers 231 are put into communication and equalized in pressure, the plug plate 240 between the two chambers 231 is opened, and the flexible mold falls into the lower chamber 231. The valve of the pressure equalizing pipe 250 is closed, the plug plate 240 is closed, and the two chambers 231 are sealed. Then, the pressure in the chamber 231 is brought to the working pressure through a pressurizing or depressurizing system;

[0082] In step S6, when cleaning the graphite, first wash the graphite with water and then perform dry ice cleaning.

[0083] The above embodiments are only the preferred embodiments of the present invention and do not limit the technical solutions of the present invention. Any technical solution that can be achieved on the basis of the above embodiments without creative labor shall be regarded as falling within the scope of the patent rights protection of the present invention.

Claims

1. A high thermal conductivity isostatic graphite preparation system, characterized in that, Comprising: A feeding device and an isostatic press, the feeding device feeding an elastic mold of the isostatic press, the feeding device including a feeding mechanism, a material pressing mechanism and a gland pressing mechanism; Wherein, the feeding mechanism includes a support, on which arbitrarily rollable universal balls are movably arranged, a driving assembly for driving the universal balls to rotate is arranged inside the support, a feeding pipe penetrates through the universal balls, and a vibrating rod is connected to the bottom of the universal balls; The material pressing mechanism includes a pressing plate, a vacuum pipe communicated with a vacuum system is arranged at the top of the pressing plate, and a second vibration assembly is arranged at the bottom of the pressing plate; The gland pressing mechanism includes a pipe rack, on which a plurality of supporting pipes are rotatably arranged, a suction nozzle is communicated with the top end of the supporting pipe, a vacuum hose communicated with the supporting pipe is arranged on the pipe rack, and the vacuum hose is communicated with the vacuum system; The isostatic press includes a high-pressure container, which is divided into a plurality of chambers from top to bottom, the chambers are in a cuboid shape, a pressurizing and pressure-relieving system for controlling the pressure rise and fall is arranged on the side of the chamber, an insertion plate is slidably arranged between two adjacent chambers up and down, a pressure equalizing pipe is communicated between two adjacent chambers up and down, and a valve, a buffer component and a throttling component are arranged on the pressure equalizing pipe; An upper gland is arranged at the top of the high-pressure container, a side chamber is arranged at the bottom of the high-pressure container, the side chamber is communicated with the bottommost chamber, and a lower gland is arranged at the top of the side chamber; A plate shell for accommodating the insertion plate to slide in and out is arranged on the high-pressure container outside the insertion plate, a hydraulic cylinder for driving the insertion plate to slide is correspondingly arranged on the plate shell, and a plate groove for sliding and sealing the edge of the insertion plate is correspondingly arranged on the inner wall of the high-pressure container; A push plate arranged vertically is arranged in the bottommost chamber, and a hydraulic cylinder for driving the push plate to slide is arranged outside the high-pressure container on the side of the push plate.

2. The high thermal conductivity isostatic graphite preparation system according to claim 1, wherein, The vibrating rod is arranged parallel to the feeding pipe, and the vibrating rod head arranged at the end of the vibrating rod is lower than the end of the feeding pipe; The driving assembly includes a driving ring arranged outside the universal ball, the driving ring is horizontally rotatably arranged inside the support, the inner wall of the driving ring is in rolling contact with the outer wall of the universal ball, an outer ring gear is arranged on the outer ring wall of the driving ring, a motor and a gear in transmission connection are correspondingly arranged inside the support, the gear meshes with the outer ring gear, a driving groove is vertically opened on the outer wall of the universal ball, an arc-shaped rack with a corresponding shape is arranged in the driving groove, a driving gear meshing with the arc-shaped rack is arranged in the driving groove, the driving gear is rotatably arranged on the driving ring, and a micro motor in transmission connection with the driving gear is correspondingly arranged on the driving ring.

3. The high thermal conductivity isostatic graphite preparation system according to claim 1, characterized in that, The shape of the pressing plate is adapted to the inner cavity of the elastic mold, a sealing ring made of an elastic material is arranged at the edge of the pressing plate, the pipe orifice of the vacuum pipe extends to the bottom of the pressing plate, the second vibration assembly at the pipe orifice of the vacuum pipe is correspondingly opened, and a filtering structure for preventing materials from being sucked in is arranged inside the pipe orifice of the vacuum pipe at the bottom of the pressing plate.

4. The high thermal conductivity isostatic graphite preparation system according to claim 1, wherein The gland pressing mechanism further includes a suction cup, the shape of the pipe rack is the same as and larger than the outer wall shape of the elastic mold, a plurality of the supporting pipes are arranged on the pipe rack at equal intervals, the bottom end of the supporting pipe is rotatably connected to the pipe rack, a micro motor for driving the supporting pipe to swing is arranged on the pipe rack, and a filtering structure for preventing materials from being sucked in is arranged inside the suction nozzle.

5. A preparation method of a high thermal conductivity isostatic graphite preparation system according to any one of claims 1 to 4, characterized in that, Including the following steps: S1. Crush and grind the raw materials, then knead them, and then crush and grind them again to obtain the powder material. S2. Feed the powder material into the elastic mold in multiple times from bottom to top through the feeding mechanism. After each feeding, compact the powder material in the elastic mold through the pressing mechanism. S3. Cover the top cover on the elastic mold through the capping mechanism, and then bind the top cover and the elastic mold to achieve sealing. S4. Place the elastic mold into the isostatic press for isostatic pressing. S5. Take out the elastic mold and the formed material, and then successively carry out primary roasting, impregnation, secondary roasting, graphitization, and cooling to obtain isostatic graphite. S6. Clean and dry the isostatic graphite. S7. Spray and cure the graphene coating on the surface of the graphite to obtain high thermal conductivity isostatic graphite. Among them, the elastic mold is placed into the isostatic press from the top. The elastic mold passes through multiple chambers successively from top to bottom in the isostatic press. The chambers inside the isostatic press have a working pressure and a transfer pressure. The working pressure is the pressure when the chamber is sealed, and the transfer pressure is the pressure for the transfer of the elastic mold when the chamber is connected to the adjacent chamber. The multiple chambers are A1, A2... A m ... A n-1 、A n , where A1 is at the top, A n is at the bottom, and the internal working pressure from A1 to A m gradually increases. The internal working pressure from A m to A n gradually decreases. The working pressure of A m is the highest, and the material is isostatically formed in A m . The working pressures of A1 and A n are atmospheric pressure. Under the working pressure, A1 and A n can be opened to put in or take out the elastic mold.

6. The preparation method of the high thermal conductivity isostatic graphite preparation system according to claim 5, characterized in that, When the elastic mold moves downward in the isostatic press, the elastic mold in the bottommost chamber is removed from the isostatic press. Then, the plug plate at the top of the bottommost chamber is opened, and the elastic mold in the upper chamber falls into the bottommost chamber. Then, the plug plate at the top of the bottommost chamber is closed. The chambers above the bottommost chamber repeat the above process in turn, so that the elastic molds in each chamber descend into the lower chamber one by one. After the elastic mold in the topmost chamber moves downward, a new elastic mold filled with materials is placed. When the elastic mold transfers between two adjacent upper and lower chambers, the valve of the pressure equalizing pipe between the two chambers is opened, the two chambers are connected and equalized in pressure, the plug plate between the two chambers is opened, the elastic mold falls into the lower chamber, the valve of the pressure equalizing pipe is closed, the plug plate is closed, and the two chambers are sealed. Then, the pressure in the chamber is adjusted to the working pressure through the pressurizing or depressurizing system.

7. The preparation method of the high thermal conductivity isostatic graphite preparation system according to claim 5, characterized in that, In the step S2, the process of each feeding by the feeding mechanism includes: the feeding pipe and the vibrating rod extend into the elastic mold. The feeding pipe feeds materials, and the vibrating rod vibrates. At the same time, the end of the feeding pipe starts from the inner side wall of the elastic mold and makes multiple circular motions step by step from outside to inside. The trajectory of the circular motion fits the internal shape of the elastic mold. The trajectories of the multiple circular motions gradually shrink from outside to inside. The coverage area of the multiple circular motions covers the cross-section of the elastic mold. Each circular motion is repeated at least twice. After the feeding is completed, the feeding mechanism withdraws from the elastic mold. After the pressing mechanism compacts the materials in the elastic mold, the next feeding is carried out. The feeding and pressing are carried out alternately until the elastic mold is filled with materials.

8. The preparation method of the high thermal conductivity isostatic graphite preparation system according to claim 5, characterized in that, In the step S2, when the pressing mechanism presses the materials, the pressing plate enters the elastic mold and descends to compact the materials. During this process, the second vibration assembly generates vibration, and the vacuum pipe evacuates the air to discharge the air in the materials and compact the materials. After the pressing is completed, the pressing plate withdraws from the elastic mold.

9. The preparation method of the high thermal conductivity isostatic pressing graphite preparation system according to claim 5, characterized in that, In the step S3, the pipe rack of the capping mechanism is located below the top cover, and the support pipe on the pipe rack swings inwards at a certain angle and then enters the inner side of the top cover side wall from the bottom of the top cover, and multiple support pipes open the bottom of the top cover so that the opening of the top cover gradually increases from top to bottom, and the top cover enters the opening of the elastic mold along with the pipe rack, and the top cover is pressed into the opening of the elastic mold until the top of the top cover covers the elastic mold. During this process, the suction nozzle performs vacuuming to discharge the air on the upper part of the elastic mold. After the top of the top cover covers the elastic mold, the pipe rack starts to descend, and the suction nozzle still maintains vacuuming during the descent. After the support pipe and the suction nozzle descend, the side wall of the top cover is tightly attached to the top side wall of the elastic mold. After the suction nozzle and the support pipe descend and completely detach from the top cover, the top cover is tightly attached to the elastic mold due to elasticity, and the pipe rack rises and evacuates from the outside of the elastic mold.

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