Formula, preparation method and preparation system of lithium feldspar-based environmentally friendly high-strength electric porcelain

Abstract

The present invention discloses a specific anti-aging lithium feldspar-based electrical porcelain formula, which includes a specific combination of lithium feldspar powder, kaolin, quartz powder, ultraviolet absorber, aluminum oxide, micro-nanoscale filler, zinc silicate and boric acid. This combination not only provides excellent mechanical strength and insulation properties, but also enhances the material's tolerance to environmental factors by adding ultraviolet absorber and other special ingredients. At the same time, the present invention adopts a special preparation method, including wet grinding, gel injection molding, pre-sintering and high-temperature sintering steps, which are designed to further improve the performance of the material and reduce the environmental impact during the production process. Through this new formula and preparation method, the electrical porcelain material of the present invention is not only superior to traditional electrical porcelain materials in performance, but also more outstanding in environmental protection, meeting the modern power industry's demand for high-performance, environmentally friendly electrical porcelain materials.

Description

Technical Field

[0001] The present invention belongs to the field of power product manufacturing, and specifically relates to a formula, a preparation method and a preparation system for lithium feldspar-based environmentally friendly high-strength electric porcelain. Background Art

[0002] Insulators play a vital role in the power industry, particularly in insulation and structural support. Traditional insulators, such as those based on potassium feldspar, kaolin, and quartz powder, while offering considerable insulation and mechanical strength, have limitations in terms of environmental performance, strength, and resistance to environmental impacts. These limitations are becoming increasingly prominent as environmental regulations strengthen and power system performance requirements increase.

[0003] Existing insulators often experience performance degradation, reduced strength, and shortened lifespans over long-term use, particularly under UV exposure and extreme climate conditions. Furthermore, the environmental impact of traditional insulator production is a growing concern. For example, some manufacturing processes may use environmentally harmful raw materials, or they may involve energy consumption and emissions.

[0004] Therefore, the development of a new type of environmentally friendly high-strength electrical porcelain material that can maintain good insulation and mechanical strength while improving tolerance to environmental factors and reducing the environmental impact during the production process has become an urgent need in this field. Summary of the Invention

[0005] The objects of the present invention are:

[0006] The purpose of the present invention is to provide a formula, preparation method and preparation system for lithium feldspar-based environmentally friendly high-strength electrical porcelain. Through its innovative formula, precise preparation method and automated preparation system, it not only improves the mechanical strength, durability and insulation of the electrical porcelain, but also enhances production efficiency and environmental friendliness. It is an important innovation in the power industry.

[0007] The technical solution adopted in the present invention is as follows:

[0008] The formula of lithium feldspar-based environmentally friendly high-strength electric porcelain includes:

[0009] Lithium feldspar powder: 55-65%;

[0010] Kaolin: 15-25%;

[0011] Quartz powder: 10-20%;

[0012] UV absorber: 1-2%;

[0013] Alumina (Al2O3): 2-5%;

[0014] Micro-nano filler: 1-3%;

[0015] Zinc silicate (Zn2SiO4): 1-3%;

[0016] Boric acid (H3BO3): 0.5-2%.

[0017] The preparation method of the lithium feldspar-based environmentally friendly high-strength electric porcelain is as follows:

[0018] ①Raw material selection: Select appropriate lithium feldspar powder, kaolin, quartz powder, UV absorber, alumina, micro-nano filler, zinc silicate and boric acid to ensure that all materials are of high purity and good quality;

[0019] ②Mixing and grinding

[0020] Premixing: Mix lithium feldspar powder, kaolin and quartz powder according to the formula ratio given above;

[0021] ③ Wet grinding: The premixed powder is mixed with water in a ball mill for wet grinding to obtain a uniform slurry;

[0022] ④Add special ingredients

[0023] Adding special ingredients: UV absorbers, alumina, micro-nano fillers, zinc silicate and boric acid during or after wet grinding;

[0024] ⑤ Drying and screening

[0025] Drying: Dry the wet-milled slurry to obtain dry powder;

[0026] Screening: Screen the dried powder to remove large particles and impurities;

[0027] ⑥Gel injection molding

[0028] Injection mold: The slurry is injected into a pre-prepared mold; the design of the mold is customized according to the shape and size of the required electrical porcelain product;

[0029] Controlled freezing process: The mold is placed in a freezing device where the temperature can be precisely controlled. By controlling the freezing rate and direction, orderly ice crystals can be formed, which act as a template to determine the pore structure of the final product.

[0030] Removal of ice crystals: After the freezing process is completed, the ice crystals are removed by heating or vacuum drying, leaving behind a porous green body structure;

[0031] ⑦Sintering

[0032] Drying: Dry the green body at room temperature or with slight heating to remove the remaining solvent;

[0033] Pre-sintering: Pre-sintering is performed at a lower temperature to enhance the strength of the green body and prepare for subsequent high-temperature sintering;

[0034] High temperature sintering: The pre-sintered product is placed in a high temperature sintering furnace for high temperature sintering; the sintering temperature and time are adjusted according to the properties of the material and the required performance;

[0035] ⑧Post-processing

[0036] Cooling: After sintering, let the product cool naturally;

[0037] Subsequent processing: Mechanical processing of the cooled product to achieve the required size and shape;

[0038] Surface treatment: Surface polishing or coating with a protective layer to further improve the product's surface quality and resistance to environmental impact.

[0039] The freezing temperature in step ⑥ is in the range of -20°C to -40°C; the freezing rate is 1-5°C / minute to control the formation of the pore structure; the drying in step ⑦ is performed at room temperature for 24 hours; pre-sintering is performed at 600°C to 800°C for about 1-2 hours to enhance the mechanical strength of the green body; and high-temperature sintering is performed at 1100°C to 1300°C for about 2-4 hours to complete the solidification and crystallization process of the electrical porcelain.

[0040] Among them, the freezing device in step ⑥ adopts a layered freezing device to achieve layered freezing of the blank, and the layered freezing device includes multiple groups of semi-cylinder molds that can be paired for mold closing, two mold changing mechanisms symmetrically arranged left and right with the vertically arranged electric porcelain core rod as the center, a transmission mechanism arranged below the mold changing mechanism, and two grouting mechanisms symmetrically arranged up and down with the electric porcelain core rod as the center; the transmission mechanism transmits the semi-cylinder molds that need to be closed and grouting to the designated position; the mold changing mechanism grabs the semi-cylinder molds respectively and closes the molds; the grouting mechanism grouts into the mold from the upper and lower ends respectively after closing the molds; the semi-cylinder molds are provided with multiple groups, and the mold cavity size gradually increases, and the next group of semi-cylinder molds is replaced after the previous group of semi-cylinder molds closes the mold, grouts, solidifies the wet blank, freezes and removes ice crystals.

[0041] Among them, the semi-cylinder mold includes a mold surface corresponding to the outer surface of the electric porcelain and a rear shell; the rear shell and the mold surface enclose a cavity; a plurality of small through holes are evenly opened on the mold surface; the small through holes connect the cavity and the mold cavity after mold closing; after mold closing, there is a distance between the mold surface of the semi-cylinder mold and the outer surface of the electric porcelain core rod, and the distance forms annular through grouting ports at the upper and lower ends of the mold cavity after mold closing; the rear shell is provided with a drain port on the lower end face in the mold closing state; the rear end face or upper end face of the rear shell in the mold closing state is provided with an exhaust port and a low-temperature liquid gas injection port.

[0042] Among them, the mold changing mechanism includes a support base body, an active telescopic arm and a lifting mechanism that can adjust the height of the support base body; the rear end of the active telescopic arm is rotatably connected to the support base body, and the front end is provided with a docking part that can be detachably docked with the rear shell of the semi-cylinder mold; the active telescopic arm is precisely rotated by controlling the component motor set on the support base body.

[0043] Among them, the docking part includes a first electromagnet part, an air extraction part and a liquid injection part; a magnetic seat is provided on the rear shell corresponding to the first electromagnet part; the air extraction port corresponds to the air extraction part; the low-temperature liquid gas injection port corresponds to the liquid injection part; when the docking part is docked with the rear shell, the first electromagnet part is energized to generate magnetism and is attracted and engaged with the magnetic seat. When engaged, the air extraction part is docked and connected with the air extraction port; the liquid injection part is docked and connected with the low-temperature liquid gas injection port.

[0044] Among them, the grouting mechanism includes a lifting arm, a butt head and a grouting head arranged at the front end of the lifting arm; the butt head presses against the electric porcelain core rod from the upper and lower ends to fix it, and the grouting head and the butt head are sealed and slidably matched; when the grouting head presses against the upper and lower ends of the semi-cylindrical mold after the mold is joined, it is connected to the grouting port.

[0045] The active telescopic arm drives the semi-cylinder mold to close at an upward tilt angle, and the tilt angle is 3° to 7°.

[0046] The method in which the layered freezing device produces a uniform pore structure during the electric porcelain forming process is as follows:

[0047] ① The lifting mechanism drives the adjustable support body to descend, and the stepper motor drives the active telescopic arm to rotate downward to correspond to the innermost semi-cylindrical mold transferred to the specified position by the transmission mechanism. The active telescopic arm extends and docks with the docking part of the semi-cylindrical mold. The first electromagnet part is energized to tightly magnetically attract the magnetic seat, the exhaust part is docked and connected with the exhaust port, and the liquid injection part is docked and connected with the low-temperature liquid gas injection port;

[0048] ② The lifting mechanism drives the adjustable support body to rise, and the stepper motor drives the active telescopic arm to rotate upward until it faces the abutted head and presses against the fixed insulator core rod from the upper and lower ends; the active telescopic arm drives the half-cylinder mold to feed toward the insulator core rod at an upward angle and makes the left and right half-cylinder molds align with each other to form a joint mold;

[0049] ③The lifting arm drives the grouting head close to the grouting port and connects with the grouting port;

[0050] ④ Pressurize the blank into the mold cavity through the grouting head and grouting port; under the action of pressure, the excess water of the blank is squeezed out from the small through-holes on the mold surface into the cavity. At the same time, air is slowly pumped out through the exhaust part and the exhaust port to form a negative pressure in the cavity to assist in draining the water; after the grouting is completed, stop the grouting, then stop pumping and open the drain port to drain the water from the drain port on the cavity;

[0051] ⑤ After draining the water in the cavity, close the drain port and inject low-temperature liquid gas into the cavity through the liquid injection part and the low-temperature liquid gas injection port. The low-temperature liquid gas injected into the cavity vaporizes and absorbs heat, and the blank is frozen through heat absorption and heat transfer;

[0052] ⑥ Continue to slowly pump air outwards to gradually form a vacuum environment in the cavity and the mold cavity. At the same time, the temperature of the blank is increased by heat transfer from the electric porcelain core rod and electric heating of the mold surface, so that the frozen water in the blank is directly sublimated and discharged, forming the first layer of green body structure with uniform porosity and stable and firm structure;

[0053] ⑦ The grouting mechanism and the mold changing mechanism act in reverse order. The grouting mechanism stops the grouting state and moves upward. The mold changing mechanism moves the semi-cylinder mold to the transmission mechanism. The transmission mechanism drives the semi-cylinder mold to be removed for cleaning and moves the next set of semi-cylinder molds with increased size to the designated position below the mold changing mechanism. Repeat the above steps to achieve the second layer of green body structure with uniform pores.

[0054] ⑧ Repeat the above steps to achieve an electrical porcelain body composed of multiple layers of green body structure with uniform pores.

[0055] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0056] 1. The lithium feldspar-based environmentally friendly high-strength electric porcelain of the present invention has a number of beneficial effects, mainly including:

[0057] Improved Mechanical Strength and Durability: By utilizing a specific combination of lithium feldspar powder, kaolin, quartz powder, and alumina, the insulators of this invention exhibit significantly improved mechanical strength and durability compared to conventional insulators. The synergistic effect of these materials ensures that the insulators maintain their structural integrity and functionality in extreme environments, such as high temperatures and high pressures.

[0058] Enhanced environmental resistance: Added UV absorbers help protect the ceramic material from the effects of UV radiation, thereby extending its life in outdoor use. This is especially important for components in power systems that are frequently exposed to sunlight.

[0059] Improved electrical insulation performance: The insulator material of the present invention provides excellent electrical insulation performance, which is crucial to ensure the safe operation of power systems. By precisely controlling the ratio of raw materials and the sintering process, a material with high resistivity and low dielectric loss can be obtained.

[0060] Environmentally friendly production process: This invention reduces the environmental impact during the production process. The raw materials used are more environmentally friendly, and the preparation methods such as wet grinding and low-temperature pre-sintering process reduce energy consumption and harmful emissions.

[0061] Increased cost-effectiveness: By optimizing the raw material combination and preparation process, the present invention not only improves the material performance, but also reduces the production cost to a certain extent. This makes high-performance electrical ceramic materials more competitive in the market.

[0062] Versatility and customization possibilities: Added ingredients such as micro- and nano-scale fillers and zinc silicate provide the material with additional functionality, such as improved thermal and chemical stability, allowing the material to be tailored to specific application needs.

[0063] Good process adaptability: The insulator formula and preparation method of the present invention are suitable for the production of various insulator products, such as insulators, capacitors and circuit boards, showing good process adaptability and broad application prospects.

[0064] In summary, the lithium feldspar-based environmentally friendly high-strength electrical porcelain of the present invention not only improves the performance of the electrical porcelain, but also takes environmental protection and cost-effectiveness into consideration, providing a new, high-performance material solution for the power industry.

[0065] 2. The present invention utilizes freeze sublimation technology to achieve a uniform pore structure inside the electric porcelain green body. The uniform pore structure plays a vital role in electric porcelain materials and has the following beneficial effects:

[0066] Improved mechanical strength: Uniformly distributed pores help evenly distribute stress in the material, reducing stress concentration points, thereby improving the overall mechanical strength and fracture resistance of the insulator. This is particularly important for ensuring the reliability of the insulator under high loads or extreme environments.

[0067] Enhanced thermal stability: The uniform pore structure facilitates the uniform distribution of heat within the material, thereby improving the thermal stability of the insulator. This thermal stability is critical for insulators in environments with large temperature fluctuations.

[0068] Improved electrical insulation performance: The uniformity of the pore structure also affects the electrical insulation properties of the insulator. Uniform pore distribution can improve the dielectric strength of the material and reduce the risk of electrical breakdown, which is crucial for insulating materials.

[0069] Improve chemical corrosion resistance: Uniform pore structure can reduce the possibility of chemical penetration and accumulation, thereby improving the chemical corrosion resistance of insulators. This is especially important for insulators used in harsh chemical environments.

[0070] Reduced weight: Uniformly distributed porosity helps reduce material weight without sacrificing strength and stability. This is an important advantage for lightweight insulator applications.

[0071] Optimize the manufacturing process: The uniform pore structure helps control shrinkage and deformation during sintering, thereby reducing scrap and improving production efficiency.

[0072] Therefore, by precisely controlling the uniformity of the pore structure, the overall performance and reliability of electrical porcelain products can be greatly improved to meet a wider range of application needs.

[0073] 3. The present invention adopts the layered freezing technology to obtain green bodies with uniform pore structure. The layered freezing technology has the following key effects on obtaining electric porcelain green bodies with uniform pore structure:

[0074] Precise control of pore size and distribution: Layered freezing technology allows for fine-tuning of pore size and distribution within the green body by precisely controlling the freezing process layer by layer. This control capability is difficult to achieve with traditional dry pressing or extrusion methods.

[0075] Achieving ordered pore formation: During the layered freezing process, water molecules form ice crystals as they freeze and are subsequently removed (e.g., by sublimation), leaving behind ordered pores. This approach produces highly ordered and uniformly distributed pores, rather than disordered or random ones.

[0076] Reduce stress concentration between pores: Uniform pore distribution helps to evenly distribute stress within the material, avoiding stress concentration and potential cracks caused by uneven pore size and distribution.

[0077] Improve the repeatability of the molding process: Due to its high control precision, the layered freezing technology can maintain a high degree of consistency in the pore structure between different production batches, thereby improving the repeatability of the product.

[0078] Improved pore structure stability: The pore structure achieved by the layered freezing technique is generally more stable than that achieved by conventional methods, which means that there is less risk of deformation and collapse of the pore structure during the subsequent drying and sintering processes.

[0079] Promote uniform shrinkage during sintering: Due to the uniform distribution of pores, the green body shrinks more evenly during sintering, thereby reducing warping and dimensional inconsistency in the finished product.

[0080] In general, the layered freezing technology can effectively generate insulator green bodies with uniform pore structures by precisely controlling the freezing process, which is of key significance for improving the overall quality and performance of insulator products.

[0081] 4. In order to obtain green bodies with uniform pores and realize highly automated layered freezing, the present invention specially designs a freezing device. The beneficial effects of the freezing device include:

[0082] The transmission mechanism is responsible for transmitting the semi-cylinder mold that needs to be closed and grouting to the designated position to realize automatic positioning of the mold.

[0083] The mold changing mechanism automatically grabs the half-cylinder mold and closes it. This automated process reduces manual operation and improves efficiency and precision.

[0084] The design of the active telescopic arm allows automatic docking of the rear shell of the semi-cylinder mold, further improving the degree of automation of the operation.

[0085] The two grouting mechanisms symmetrically arranged up and down with the electric porcelain core rod as the center ensure that the slurry is evenly injected from both ends of the mold, thereby achieving uniform distribution of the slurry in the mold.

[0086] The design of the butt head and grouting head ensures precise control of the grouting process and uniform distribution of the slurry in the mold.

[0087] The design of the semi-cylinder mold includes a profile and a rear shell corresponding to the outer surface of the insulator, as well as multiple small through holes, which ensure the uniform distribution of the slurry and the effective discharge of moisture.

[0088] The design of the cryogenic liquid gas injection port and the exhaust port combines the functions of the exhaust and liquid injection parts to achieve precise temperature and pressure control inside the mold, providing ideal conditions for the formation of a uniform pore structure.

[0089] The design of drain ports and fine through-holes helps remove excess water during the grouting process, thereby forming a more uniform pore structure during the subsequent freezing process.

[0090] Precise freezing control is achieved through air extraction and low-temperature liquid gas injection, which allows the slurry to freeze layer by layer to form a uniform pore structure.

[0091] By tilting the mold upward and designing the corresponding mold shape and structure, it can be ensured that the bottom surface of the formed electric porcelain has a concave arc surface, so that the downward flow of water after installation is cut off to avoid the formation of water lines, and it can also facilitate demoulding.

[0092] By repeating the above steps, a multi-layer green body structure with uniform porosity is achieved. The processing of each layer is automated, thus achieving uniform and efficient manufacturing of the entire electrical porcelain body.

[0093] In summary, through these structural innovations and automated control, the layered freezing device not only improves production efficiency and billet quality, but also achieves precise manufacturing of uniform pore structures in electrical porcelain billets, greatly improving the performance of the final product. BRIEF DESCRIPTION OF THE DRAWINGS

[0094] Figure 1 It is a structural schematic diagram of the insulator of the present invention;

[0095] Figure 2 It is a structural schematic diagram of the stratified freezing device of the present invention;

[0096] Figure 3 It is a partial structural schematic diagram of the stratified freezing device of the present invention;

[0097] Figure 4 for Figure 2 An enlarged schematic diagram of the middle circle A;

[0098] Figure 5 It is a structural schematic diagram of the semi-cylinder mold of the present invention.

[0099] Markings in the figure: 1. Semi-cylinder mold; 11. Molding surface; 12. Rear shell; 121. Magnetic seat; 13. Cavity; 14. Grouting port; 15. Drain port; 16. Exhaust port; 17. Low-temperature liquid gas injection port; 2. Mold changing mechanism; 21. Support seat; 22. Active telescopic arm; 23. Lifting mechanism; 24. First electromagnet part; 25. Exhaust part; 26. Liquid injection part; 3. Transmission mechanism; 4. Grouting mechanism; 41. Lifting arm; 42. Grouting head; 43. Butt head; 5. Electric porcelain core rod. DETAILED DESCRIPTION

[0100] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0101] The formula of lithium feldspar-based environmentally friendly high-strength electric porcelain includes:

[0102] Lithium feldspar powder: 55-65%;

[0103] Kaolin: 15-25%;

[0104] Quartz powder: 10-20%;

[0105] UV absorber: 1-2%;

[0106] Alumina (Al2O3): 2-5%;

[0107] Micro-nano filler: 1-3%;

[0108] Zinc silicate (Zn2SiO4): 1-3%;

[0109] Boric acid (H3BO3): 0.5-2%.

[0110] Among them, the UV absorber can be selected from:

[0111] Titanium dioxide (TiO2): has excellent UV absorption capabilities and is often used to enhance the UV resistance of materials. It is an insulating material and, in common applications, does not conduct electricity. It is widely used to enhance the UV resistance of materials without affecting the insulation properties of insulators.

[0112] Benzophenone compounds: These organic UV absorbers protect the ceramic material by absorbing UV rays and converting them into heat. These organic UV absorbers are generally insulating and non-conductive, so they do not affect the insulating properties of the ceramic.

[0113] Micro-nano fillers can be selected:

[0114] Nano-calcium silicate (CaSiO3): Improves the mechanical strength and heat resistance of materials. It is an insulating material used to enhance the mechanical strength and heat resistance of electrical porcelain without increasing electrical conductivity.

[0115] Nano-alumina (Al2O3): can enhance the mechanical properties and thermal stability of insulators. It is an excellent insulating material and is widely used to enhance the mechanical properties and insulation of insulators.

[0116] Nano silicon powder: Improves the insulation performance and wear resistance of electrical porcelain. It is also insulating and is usually used to improve the insulation performance and wear resistance of materials.

[0117] Furthermore, the preparation method of the lithium feldspar-based environmentally friendly high-strength electric porcelain is:

[0118] ①Raw material selection: Select appropriate lithium feldspar powder, kaolin, quartz powder, UV absorber, alumina, micro-nano filler, zinc silicate and boric acid to ensure that all materials are of high purity and good quality;

[0119] ②Mixing and grinding

[0120] Premixing: Mix lithium feldspar powder, kaolin and quartz powder according to the formula ratio given above;

[0121] ③ Wet grinding: The premixed powder is mixed with water in a ball mill for wet grinding to obtain a uniform slurry;

[0122] ④Add special ingredients

[0123] Adding special ingredients: UV absorbers, alumina, micro-nano fillers, zinc silicate and boric acid during or after wet grinding;

[0124] ⑤ Drying and screening

[0125] Drying: Dry the wet-milled slurry to obtain dry powder;

[0126] Screening: Screen the dried powder to remove large particles and impurities;

[0127] ⑥Gel injection molding

[0128] Injection mold: The slurry is injected into a pre-prepared mold; the design of the mold is customized according to the shape and size of the required electrical porcelain product;

[0129] Controlled freezing process: The mold is placed in a freezing device where the temperature can be precisely controlled. By controlling the freezing rate and direction, orderly ice crystals can be formed, which act as a template to determine the pore structure of the final product.

[0130] Removal of ice crystals: After the freezing process is completed, the ice crystals are removed by heating or vacuum drying, leaving behind a porous green body structure;

[0131] ⑦Sintering

[0132] Drying: Dry the green body at room temperature or with slight heating to remove the remaining solvent;

[0133] Pre-sintering: Pre-sintering is performed at a lower temperature to enhance the strength of the green body and prepare for subsequent high-temperature sintering;

[0134] High temperature sintering: The pre-sintered product is placed in a high temperature sintering furnace for high temperature sintering; the sintering temperature and time are adjusted according to the properties of the material and the required performance;

[0135] ⑧Post-processing

[0136] Cooling: After sintering, let the product cool naturally;

[0137] Subsequent processing: Mechanical processing of the cooled product to achieve the required size and shape;

[0138] Surface treatment: Polishing or coating of protective layer to further improve the surface quality and resistance to environmental impact of the product.

[0139]

[0140]

[0141] The ultraviolet absorber is titanium dioxide, and the micro-nano filler is nano calcium silicate.

[0142] The samples are prepared in the specified size and have a clean surface without cracks.

[0143] Dielectric strength test: Apply DC or AC high voltage to the sample until it breaks, record the breaking voltage and corresponding thickness, and calculate the dielectric strength (kV / mm).

[0144] Mechanical strength test, measuring compressive strength: using a pressure testing machine, gradually increase the pressure until the sample breaks, and record the maximum bearing force (MPa).

[0145] Thermal stability test: Place the sample in a thermal cycler, raise the temperature from room temperature to high temperature (600°C), keep it for a period of time, and then cool it to room temperature. Repeat this cycle multiple times to check the changes in structure and performance.

[0146] UV resistance test: Expose to a specific UV intensity for a certain period of time (500 hours) to check changes in color, hardness, and other physical properties.

[0147] Chemical stability test: Immerse the sample in acid, alkali or salt solution and detect weight change, surface erosion and performance degradation after a certain period of time.

[0148] Compared to existing mainstream products, the present invention demonstrates significant advantages in mechanical strength, insulation performance, and thermal stability. This is primarily due to the optimized formulation and preparation process of the environmentally friendly, high-strength lithium-feldspar-based insulator, particularly the addition of UV absorbers and micro-nanoscale fillers, as well as the controlled freezing temperature and rate, resulting in a final product with superior performance.

[0149] Furthermore, the freezing temperature range in step ⑥ is: -20°C to -40°C; the freezing rate is: 1-5°C / minute to control the formation of the pore structure; the drying in step ⑦ is drying at room temperature for 24 hours; pre-sintering is performed at 600°C to 800°C for about 1-2 hours to enhance the mechanical strength of the green body; and high-temperature sintering is performed at 1100°C to 1300°C for about 2-4 hours to complete the solidification and crystallization process of the electrical porcelain.

[0150] For further information, see Figures 1 to 5The freezing device in step ⑥ adopts a layered freezing device to achieve layered freezing of the blank, and the layered freezing device includes multiple groups of semi-cylinder molds 1 that can be paired for mold closing, two mold changing mechanisms 2 symmetrically arranged left and right with a vertically arranged electric porcelain core rod 5 as the center, a transmission mechanism 3 arranged below the mold changing mechanism 2, and two grouting mechanisms 4 symmetrically arranged up and down with the electric porcelain core rod 5 as the center; the transmission mechanism 3 transmits the semi-cylinder mold 1 that needs to be closed and grouting to a designated position; the mold changing mechanism 2 grabs the semi-cylinder molds 1 respectively and closes the mold; the grouting mechanism 4 grouts into the mold from the upper and lower ends after closing the mold; the semi-cylinder molds 1 are provided with multiple groups, and the mold cavity size gradually increases. After the previous group of semi-cylinder molds 1 is closed, grouting, condensing wet blanks, freezing and removing ice crystals, the next group of semi-cylinder molds 1 is replaced.

[0151] Furthermore, the semi-cylinder mold 1 includes a mold surface 11 corresponding to the outer surface of the electric porcelain and a rear shell 12; the rear shell 12 and the mold surface 11 enclose a cavity 13; a plurality of small through holes are evenly opened on the mold surface 11; the small through holes connect the cavity 13 and the mold cavity after mold closing; after mold closing, there is a distance between the mold surface 11 of the semi-cylinder mold 1 and the outer surface of the electric porcelain core rod 5, and the distance forms annular through grouting ports 14 at the upper and lower ends of the mold cavity after mold closing; the rear shell 12 is provided with a drain port 15 on the lower end face in the mold closing state; the rear end face or upper end face of the rear shell 12 in the mold closing state is provided with an exhaust port 16 and a low-temperature liquid gas injection port 17.

[0152] Furthermore, the mold changing mechanism 2 includes a support base body 21, an active telescopic arm 22 and a lifting mechanism 23 that can adjust the height of the support base body 21; the rear end of the active telescopic arm 22 is rotatably connected to the support base body 21, and the front end is provided with a docking portion that can be detachably docked with the rear shell body 12 of the semi-cylinder mold 1; the active telescopic arm 22 is precisely rotated by controlling the component motor provided on the support base body 21.

[0153] Furthermore, the docking part includes a first electromagnet part 24, an air extraction part 25 and a liquid injection part 26; a magnetic seat 121 is provided on the rear shell body 12 corresponding to the first electromagnet part 24; the air extraction port 16 corresponds to the air extraction part 25; the low-temperature liquid gas injection port 17 corresponds to the liquid injection part 26; when the docking part is docked with the rear shell body 12, the first electromagnet part 24 is energized to generate magnetism and is attracted and engaged with the magnetic seat 121. When engaged, the air extraction part 25 is docked and connected with the air extraction port 16; the liquid injection part 26 is docked and connected with the low-temperature liquid gas injection port 17.

[0154] Furthermore, the grouting mechanism 4 includes a lifting arm 41, a butt 43 and a grouting head 42 arranged at the front end of the lifting arm 41; the butt 43 presses against the electric porcelain core rod 5 from the upper and lower ends to fix it, and the grouting head 42 and the butt 43 are sealed and slidably matched; when the grouting head 42 presses against the upper and lower ends of the semi-cylindrical mold 1 after the mold is engaged, it is connected to the grouting port 14.

[0155] Furthermore, the active telescopic arm 22 drives the semi-cylinder mold 1 to close at an upward tilt angle, and the tilt angle is 3° to 7°.

[0156] Furthermore, the method for the layered freezing device to produce a uniform pore structure during the electric porcelain forming process is:

[0157] ① The lifting mechanism 23 drives the adjustable support base 21 to descend, and the stepping motor drives the active telescopic arm 22 to rotate downward to correspond to the innermost semi-cylindrical mold 1 transferred to the designated position by the transfer mechanism 3. The active telescopic arm 22 extends and docks with the docking portion of the semi-cylindrical mold 1. The first electromagnet portion 24 is energized to tightly magnetically attract the magnetic seat 121. The exhaust portion 25 is docked and connected to the exhaust port 16, and the liquid injection portion 26 is docked and connected to the low-temperature liquid gas injection port 17.

[0158] ② The lifting mechanism 23 drives the adjustable support base 21 to rise, and the stepping motor drives the active telescopic arm 22 to rotate upward until it faces the abutted head 43 and abuts the fixed insulator core rod 5 from both ends; the active telescopic arm 22 drives the half-cylinder mold 1 at an upward angle to feed toward the insulator core rod 5 and make the left and right half-cylinder molds 1 align with each other;

[0159] ③ The lifting arm 41 drives the grouting head 42 to approach the grouting port 14 and connect with the grouting port 14;

[0160] ④ Pressurize the blank into the mold cavity through the grouting head 42 and the grouting port 14; under the pressure, excess water in the blank is squeezed out from the small through-holes on the molding surface 11 into the cavity 13. At the same time, air is slowly pumped out through the exhaust part 25 and the exhaust port 16 to form a negative pressure in the cavity 13 to assist in draining the water; after the grouting is completed, the grouting is stopped, and then the air pumping is stopped and the drain port 15 is opened to allow the water to be discharged from the drain port 15 on the cavity 13;

[0161] ⑤ After draining the water in the cavity 13, close the drain port 15 and inject cryogenic liquid gas into the cavity 13 through the liquid injection portion 26 and the cryogenic liquid gas injection port 17. The cryogenic liquid gas injected into the cavity 13 vaporizes and absorbs heat, and the blank is frozen through heat absorption and heat transfer;

[0162] ⑥ Continue to slowly pump air outwards to gradually form a vacuum environment in the cavity 13 and the mold cavity. At the same time, the temperature of the blank is increased by heat transfer from the electric porcelain core rod and electric heating of the molding surface 11, so that the frozen water in the blank is directly sublimated and discharged, forming the first layer of green body structure with uniform porosity and stable and firm structure;

[0163] ⑦ The grouting mechanism 4 and the mold changing mechanism 2 act in reverse order. The grouting mechanism 4 stops the grouting state and moves upward. The mold changing mechanism 2 moves the semi-cylinder mold 1 onto the conveying mechanism 3. The conveying mechanism 3 drives the semi-cylinder mold 1 to be removed for cleaning and moves the next set of semi-cylinder molds 1 with increased size to the designated position below the mold changing mechanism 2. Repeat the above steps to achieve the second layer of green body structure with uniform pores.

[0164] ⑧ Repeat the above steps to achieve an electrical porcelain body composed of multiple layers of green body structure with uniform pores.

[0165] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a lithium feldspar-based environmentally friendly high-strength electrical porcelain, characterized in that: The formula of the lithium feldspar-based environmentally friendly high-strength electric porcelain includes: lithium feldspar powder: 55-65%; kaolin: 15-25%; quartz powder: 10-20%; ultraviolet absorber: 1-2%; aluminum oxide (Al2O3): 2-5%; micro-nano filler: 1-3%; zinc silicate (Zn2SiO4): 1-3%; boric acid (H3BO3): 0.5-2%. The preparation method includes the following steps: ①Raw material selection: Select appropriate lithium feldspar powder, kaolin, quartz powder, UV absorber, alumina, micro-nano filler, zinc silicate and boric acid to ensure that all materials are of high purity and good quality; ②Mixing and grinding: Mix the lithium feldspar powder, kaolin and quartz powder according to the formula ratio given above; ③ Wet grinding: The premixed powder is mixed with water in a ball mill for wet grinding to obtain a uniform slurry; ④Add special ingredients: add UV absorbers, alumina, micro-nano fillers, zinc silicate and boric acid during or after wet grinding; ⑤ Drying and screening: Drying: Dry the wet-milled slurry to obtain dry powder; Screening: Screen the dried powder to remove large particles and impurities; ⑥Gel injection molding: Injection mold: The slurry is injected into a pre-prepared mold; the design of the mold is customized according to the shape and size of the required electrical porcelain product; Controlled freezing process: The mold is placed in a freezing device where the temperature can be precisely controlled. By controlling the freezing rate and direction, orderly ice crystals can be formed, which act as a template to determine the pore structure of the final product. Removal of ice crystals: After the freezing process is completed, the ice crystals are removed by heating or vacuum drying, leaving behind a porous green body structure; ⑦Sintering: Drying: Dry the green body at room temperature or with slight heating to remove the remaining solvent; Pre-sintering: Pre-sintering is performed at a lower temperature to enhance the strength of the green body and prepare for subsequent high-temperature sintering; High temperature sintering: The pre-sintered product is placed in a high temperature sintering furnace for high temperature sintering; the sintering temperature and time are adjusted according to the properties of the material and the required performance; ⑧Post-processing: Cooling: After sintering, let the product cool naturally; Subsequent processing: Mechanical processing of the cooled product to achieve the required size and shape; Surface treatment: polishing or coating the surface with a protective layer to further improve the surface quality and environmental resistance of the product; The freezing device in step ⑥ uses a layered freezing device to achieve layered freezing of the blank, and the layered freezing device includes multiple groups of semi-cylinder molds (1) that can be matched and molded, two mold changing mechanisms (2) symmetrically arranged with a vertically arranged electric porcelain core rod (5) as the center, a transmission mechanism (3) arranged below the mold changing mechanism (2), and two grouting mechanisms (4) symmetrically arranged with the electric porcelain core rod (5) as the center; the transmission mechanism (3) transmits the semi-cylinder mold (1) that needs to be molded and grouting to a designated position; the mold changing mechanism (2) respectively grabs the semi-cylinder mold (1) and closes the mold; the grouting mechanism (4) respectively injects grout into the mold from the upper and lower ends after the mold is closed; the semi-cylinder mold (1) is provided with multiple groups, and the mold cavity size gradually increases, and the next group of semi-cylinder molds (1) is replaced after the previous group of semi-cylinder molds (1) is molded, grouting, solidifying the wet blank, freezing, and removing ice crystals; The semi-cylinder mold (1) comprises a mold surface (11) corresponding to the outer surface of the electric porcelain and a rear shell (12); the rear shell (12) and the mold surface (11) enclose a cavity (13); a plurality of fine through holes are evenly provided on the mold surface (11); the fine through holes connect the cavity (13) and the mold cavity after mold closing; after mold closing, there is a distance between the mold surface (11) of the semi-cylinder mold (1) and the outer surface of the electric porcelain core rod (5), and the distance forms annular through-hole grouting ports (14) at the upper and lower ends of the mold cavity after mold closing; the rear shell (12) is provided with a drain port (15) on the lower end face in the mold closing state; the rear end face or the upper end face of the rear shell (12) in the mold closing state is provided with an air extraction port (16) and a low-temperature liquid gas injection port (17).

2. The method for preparing the lithium feldspar-based environmentally friendly high-strength electrical porcelain according to claim 1, wherein: The freezing temperature in step ⑥ is in the range of -20°C to -40°C; the freezing rate is 1-5°C / minute to control the formation of the pore structure; the drying in step ⑦ is performed at room temperature for 24 hours; a pre-sintering at 600°C to 800°C for about 1-2 hours is performed to enhance the mechanical strength of the green body; and a high-temperature sintering at 1100°C to 1300°C for about 2-4 hours is performed to complete the solidification and crystallization process of the insulator.

3. The method for preparing the lithium feldspar-based environmentally friendly high-strength electrical porcelain according to claim 1, wherein: The mold changing mechanism (2) comprises a support base (21), an active telescopic arm (22), and a lifting mechanism (23) capable of adjusting the height of the support base (21); the rear end of the active telescopic arm (22) is rotatably connected to the support base (21), and the front end is provided with a docking portion that can be detachably docked with the rear shell (12) of the semi-cylinder mold (1); the active telescopic arm (22) is precisely rotated by controlling a component motor provided on the support base (21).

4. The method for preparing the lithium feldspar-based environmentally friendly high-strength electrical porcelain according to claim 3, characterized in that: The docking portion comprises a first electromagnet portion (24), an air extraction portion (25) and a liquid injection portion (26); a magnetic seat (121) is provided on the rear shell (12) corresponding to the first electromagnet portion (24); the air extraction port (16) corresponds to the air extraction portion (25); the low-temperature liquid gas injection port (17) corresponds to the liquid injection portion (26); when the docking portion is docked with the rear shell (12), the first electromagnet portion (24) is energized to generate magnetism and is attracted and engaged with the magnetic seat (121); when engaged, the air extraction portion (25) is docked and connected with the air extraction port (16); and the liquid injection portion (26) is docked and connected with the low-temperature liquid gas injection port (17).

5. The method for preparing the lithium feldspar-based environmentally friendly high-strength electrical porcelain according to claim 4, characterized in that: The grouting mechanism (4) comprises a lifting arm (41), a butt head (43) and a grouting head (42) arranged at the front end of the lifting arm (41); the butt head (43) butts against the electric porcelain core rod (5) from the upper and lower ends to fix it, and the grouting head (42) and the butt head (43) are in sealing and sliding cooperation; when the grouting head (42) butts against the upper and lower ends of the semi-cylinder mold (1) after the mold is engaged, it is connected to the grouting port (14).

6. The method for preparing the lithium feldspar-based environmentally friendly high-strength electrical porcelain according to claim 5, characterized in that: The active telescopic arm (22) drives the semi-cylinder mold (1) to close the mold at an upward tilt angle, and the tilt angle is 3° to 7°.

7. The method for preparing the lithium feldspar-based environmentally friendly high-strength electrical porcelain according to claim 6, characterized in that: The method for the layered freezing device to produce a uniform pore structure during the electric porcelain forming process is: ① The lifting mechanism (23) drives the adjustable support seat (21) to descend, and the stepping motor drives the active telescopic arm (22) to rotate downward to correspond to the innermost semi-cylindrical mold (1) transmitted to the designated position by the transmission mechanism (3), the active telescopic arm (22) extends and docks with the docking portion of the semi-cylindrical mold (1), the first electromagnet part (24) is energized to be tightly magnetically attracted to the magnetic seat (121), the air extraction part (25) is docked and connected with the air extraction port (16), and the liquid injection part (26) is docked and connected with the low-temperature liquid gas injection port (17); ② The lifting mechanism (23) drives the adjustable support base (21) to rise, and the stepping motor drives the active telescopic arm (22) to rotate upward until it faces the abutted head (43) and abuts against the fixed electric porcelain core rod (5) from both ends; the active telescopic arm (22) drives the semi-cylinder mold (1) to feed toward the electric porcelain core rod (5) at an inclined upward angle and makes the left and right semi-cylinder molds (1) butt against the mold; ③ The lifting arm (41) drives the grouting head (42) to approach the grouting port (14) and connect with the grouting port (14); ④ Pressurizing the blank into the mold cavity through the grouting head (42) and the grouting port (14); under the pressure, excess water in the blank is squeezed out from the small through-holes on the molding surface (11) into the cavity (13); at the same time, air is slowly pumped outward through the air pumping portion (25) and the air pumping port (16), so that a negative pressure is formed in the cavity (13) to assist in draining the water; after the grouting is completed, the grouting is stopped, and then the air pumping is stopped and the drain port (15) is opened to allow the water to be discharged from the drain port (15) on the cavity (13); ⑤ After draining the water in the cavity (13), the drain port (15) is closed, and cryogenic liquid gas is injected into the cavity (13) through the liquid injection portion (26) and the cryogenic liquid gas injection port (17). The cryogenic liquid gas injected into the cavity (13) vaporizes and absorbs heat, and the blank is frozen through heat absorption and heat transfer; ⑥ Continue to slowly pump air outwards, so that the cavity (13) and the mold cavity gradually form a vacuum environment. At the same time, the temperature of the blank is increased by heat transfer of the electric porcelain core rod and electric heating of the mold surface (11), so that the frozen water in the blank is directly sublimated and discharged, forming the first layer of green body structure with uniform pores and stable and firm structure; ⑦ The grouting mechanism (4) and the mold changing mechanism (2) move in reverse order, the grouting mechanism (4) releases the grouting state and moves upward, the mold changing mechanism (2) moves the semi-cylinder mold (1) onto the transmission mechanism (3), the transmission mechanism (3) drives the semi-cylinder mold (1) to be removed and cleaned, and moves the next set of semi-cylinder molds (1) with increased size to the designated position below the mold changing mechanism (2); repeat the above steps to realize the second layer of green body structure with uniform pores; ⑧ Repeat the above steps to achieve an electrical porcelain body composed of multiple layers of green body structure with uniform pores.

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