Forming device and forming method

Abstract

The invention provides a forming device and a forming method, and relates to the field of graphite product manufacturing, the forming device is used for producing large-size graphite products, and the forming device comprises a pressing die, an inner die core, an outer die and a flexible film; the inner mold core is fixed to the bottom in the outer mold, an opening is formed in the top of the outer mold, and the pressing mold is pressed downwards to be connected with the opening of the outer mold. The flexible film is arranged on the outer surface of the inner mold core in a wrapping mode, the flexible film is connected with the inner mold core in a sealed mode, a pressurizing cavity is formed between the flexible film and the inner mold core, and a mold cavity matched with a formed product is formed among the flexible film, the outer mold and the pressing mold; and the pressing mold, the inner mold core, the flexible mold and the outer mold jointly extrude materials into a formed product.

Description

Technical Field

[0001] The invention relates to the manufacture of graphite products, in particular to a large-scale forming device and a forming method. Background Art

[0002] Lithium batteries are widely used in automobiles and energy storage applications. Positive and negative electrode materials are the primary components of lithium batteries and contribute significantly to their production costs. The production of these materials requires a significant amount of carbon graphite crucibles and graphite saggers.

[0003] Existing production methods for carbon graphite crucible molding, such as Figure 1 As shown, currently, a kneaded crucible paste 1 is placed into a mold cavity surrounded by a crucible outer mold 2, and a crucible die 3 is pressed down into the mold cavity to squeeze the crucible paste 1 into shape. The upper portion of the formed crucible is formed by the crucible die 3, which squeezes the crucible paste 1 upward. However, the fluidity of the crucible paste 1 is poor, and during the extrusion process, it is affected by the friction between the inner wall of the crucible die 3 and the crucible outer mold 2, resulting in a large difference in density between the upper and lower portions of the extruded crucible and poor structural uniformity. As a result, the upper portion of the crucible is easily damaged during use, and even longitudinal cracks may appear.

[0004] Due to the poor quality of existing carbon graphite crucibles, the production of positive and negative electrode materials for lithium batteries requires the consumption of larger quantities of carbon graphite crucibles, resulting in high costs for producing lithium batteries. Summary of the Invention

[0005] The present invention aims to provide a molding device and molding method that eliminates the need for large-scale flow of extruded material, resulting in a stable structure and uniform performance of the molded product. Furthermore, the extrusion molding process of the molding device ensures that the shape and size of the molded product do not affect its performance and quality.

[0006] The following is a brief summary of one or more aspects to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceivable aspects and is neither intended to identify key or critical elements of all aspects nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that will be provided later.

[0007] One of the embodiments of the present invention provides a molding device, which includes a compression mold, an inner mold core, an outer mold and a flexible membrane; the inner mold core is fixed to the bottom of the outer mold, the top of the outer mold is provided with an opening, and the compression mold is pressed down until it is connected with the opening of the outer mold; the flexible membrane is covered on the outer surface of the inner mold core, the flexible membrane is sealed with the inner mold core, a pressurized cavity is formed between the flexible membrane and the inner mold core, and a mold cavity suitable for the molded product is formed between the flexible membrane and the outer mold and the compression mold; the compression mold, the inner mold core, the flexible membrane and the outer mold jointly extrude the material into a molded product.

[0008] In some embodiments, the inner mold core is a hollow structure with a cavity, a through hole is provided on the inner mold core, the pressure cavity is connected to the cavity through the through hole, a pressure channel is provided on the inner mold core for connecting with a pressure piece, the pressure piece is used to introduce gas or liquid or a gas-liquid mixture into the pressure cavity for pressurization, and the cavity of the inner mold core is connected to the pressure piece through the pressure channel.

[0009] In some embodiments, the flexible film is a uniform structure with elasticity, and the shape of the flexible film is adapted to the shape of the inner mold core.

[0010] In some embodiments, the edge of the flexible film covering the inner mold core is pressed against the bottom of the inner mold core to achieve a sealed connection between the flexible film and the inner mold core.

[0011] In some embodiments, the outer shape of the inner mold core corresponds to the inner shape of the molded article.

[0012] In some embodiments, the inner shape of the outer mold conforms to the outer shape of the molded article.

[0013] In some embodiments, the cross-sectional shape of the inner mold core includes at least one of a circle, a square, a honeycomb, a grid, a ring, or a gear.

[0014] In some embodiments, the outer mold includes a side mold and a bottom mold, the inner mold core is arranged on the bottom mold, the side mold is a structure with both ends through, the first end of the side mold is detachably connected to the peripheral side of the bottom mold, and the pressure mold can cover the opening of the second end of the side mold.

[0015] In some embodiments, a heating component is provided at least one of the compression mold, the inner mold core, and the outer mold, and the heating component is used to heat the corresponding mold temperature.

[0016] In some embodiments, the molding device includes a support column and a first power member. The die is movably connected to the support column. Driven by the first power member, the die moves away from or closer to the outer mold along the support column.

[0017] In some embodiments, the molding device includes a fixing seat, which is used to fix the first power member, and the fixing seat is fixed to the support column.

[0018] In some embodiments, the molding device includes a support base for supporting the outer mold.

[0019] In some embodiments, the outer mold includes a side mold and a bottom mold, the inner mold core is arranged on the bottom mold, the side mold is a structure with both ends through, the first end of the side mold is detachably connected to the peripheral side of the bottom mold, and the pressure mold can cover the second end of the side mold; the molding device includes a support seat, the support seat is used to support the outer mold, the bottom mold is installed on the support seat, and a positioning structure is provided on the support seat, and the side mold is positioned and docked with the bottom mold through the positioning structure.

[0020] In some embodiments, the material includes organic matter, inorganic matter or a mixture thereof, and the mixture includes coke powder, asphalt, graphite powder, alloy powder, powdered, granular or fibrous plastic or a combination thereof.

[0021] In some embodiments, the material includes a dispersant, which is used to evenly distribute the material in the mold cavity; the molding device includes an adsorption filter, which is arranged on the inner wall of the mold cavity formed by the pressure mold and the outer mold. When the material is extruded, the adsorption filter is used to adsorb and filter the dispersant contained in the material.

[0022] In some embodiments, the dispersant includes, but is not limited to, water, alcohol, methanol, formaldehyde, benzene, toluene, and phenol.

[0023] The embodiments of this specification also relate to a molding method, which is applied to the above-mentioned molding device; the molding method includes: filling material into the mold cavity; pressing the mold down until it connects with the opening of the outer mold; under the pressure of the mold, the mold, inner mold core and outer mold jointly extrude the material into a molded product.

[0024] In some embodiments, the molding device includes a flexible membrane, which is coated on the outer surface of the inner mold core. The flexible membrane is sealed and connected to the inner mold core, and a pressurized cavity is formed between the flexible membrane and the inner mold core. The molding method includes: after the mold is pressed down until it is connected with the opening of the outer mold, the pressure in the pressurized cavity is increased to the required pressure value. The pressure in the pressurized cavity causes the flexible membrane to expand, and the material in the extrusion mold cavity is formed into a molded product.

[0025] In some embodiments, the outer mold includes a side mold and a bottom mold, the inner mold core is arranged on the bottom mold, the side mold is a structure with both ends through, the first end of the side mold is detachably connected to the peripheral side of the bottom mold, and the pressure mold can cover the second end of the side mold; the molding method includes: after the extruded material is molded, the pressure in the pressurized chamber is released, the side mold and the bottom mold are disassembled, and the side mold is removed to obtain a molded product.

[0026] The embodiments of this specification also relate to a graphite product, which is prepared by the above-mentioned molding device or according to the above-mentioned molding method. The graphite product includes a graphite crucible, a graphite tube, and a graphite sagger.

[0027] In some embodiments, the length dimension of the graphite product is greater than or equal to 500 mm, the width dimension of the graphite product is greater than or equal to 500 mm, and the height dimension of the graphite product is greater than or equal to 800 mm.

[0028] In some embodiments, the bulk density difference of the graphite article as a whole is less than 0.02 g / cm 3 .

[0029] The embodiments of this specification also relate to a molded product, which is prepared according to the above-mentioned molding device or the above-mentioned molding method, and the molded product is extruded from at least one of organic matter, inorganic matter or a mixture thereof, and the mixture of organic matter, inorganic matter or a mixture thereof includes coke powder, asphalt, graphite powder, alloy powder, powdered, granular or fibrous plastic.

[0030] In some embodiments, the bulk density difference of the molded article as a whole is less than 0.02 g / cm 3 .

[0031] The molding device disclosed herein charges a fixed amount of material into a cavity formed between the outer mold and the periphery of an inner mold core through an opening at the top of an outer mold. The material flows naturally under the influence of gravity and is initially formed within the confines of the mold cavity. The die is then pressed down until it engages the opening at the top of the outer mold, extruding the material. During the extrusion process, the material does not experience extensive flow, resulting in uniform extrusion force. The resulting molded product exhibits excellent structural uniformity, stable performance, and a service life extended by over 20%.

[0032] Since the material does not need to flow over a large range during the extrusion process, there is almost no or no friction relative to the inner mold core and the outer mold, and the size and structure of the molded product are not limited. The existing round crucible can be replaced by the square crucible produced by this device. On the basis of the increase in the number of times it can be used, the capacity of the square crucible of the same size is 25% greater than that of the round crucible, which can greatly reduce the cost of graphitization production. At the same time, the molded products prepared using the molding device designed by the present invention have significantly improved quality compared to existing products, longer service life, and significantly increased number of uses. When the molded products are used to produce positive and negative electrode materials for lithium batteries, the number of molded products used to produce the same amount of positive and negative electrode materials for lithium batteries is greatly reduced, which reduces the production cost of lithium batteries and has obvious economic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above features and advantages of the present invention will be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, components are not necessarily drawn to scale, and components with similar related properties or characteristics may have the same or similar reference numerals. Among them:

[0034] Figure 1It is a structural diagram of crucible manufacturing equipment;

[0035] Figure 2 is a schematic structural diagram of a forming device according to some embodiments;

[0036] Figure 3 is a schematic diagram of a cross-sectional shape of an inner mold core according to some embodiments;

[0037] Figure 4 Schematic diagrams of cross-sectional shapes of inner mold cores according to other embodiments;

[0038] Figure 5 is a schematic diagram of a cross-sectional shape of an inner mold core according to some embodiments;

[0039] Figure 6 The inner mold core has Figure 5 A schematic diagram of the structure of the cross-sectional shape shown;

[0040] Figure 7 is a schematic diagram of a connection structure between a flexible film and an inner mold core according to some embodiments;

[0041] Figure 8 Schematic diagram of the configuration of an adsorption filter according to some embodiments.

[0042] Description of reference numerals:

[0043] 100-forming device;

[0044] 110-pressing die;

[0045] 120-Inner mold core;

[0046] 130-external mold;

[0047] 131- bottom mold;

[0048] 1311-workpiece seat;

[0049] 132-side mold;

[0050] 140-mold cavity;

[0051] 150-flexible membrane;

[0052] 160- pressurized channel;

[0053] 170-support column;

[0054] 180-first power member;

[0055] 181-fixed seat;

[0056] 190-support seat;

[0057] 61-Adsorption filter. DETAILED DESCRIPTION

[0058] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Note that the various aspects described below with reference to the accompanying drawings and specific embodiments are merely exemplary and should not be construed as limiting the scope of protection of the present invention.

[0059] It should be understood that the terms "system," "device," "unit," and / or "module" used herein are a method for distinguishing different components, elements, parts, portions, or assemblies at different levels. However, other terms may be used to replace a term if they achieve the same purpose.

[0060] It is understood that the technical terms that may be involved in the description of this specification, such as "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., which indicate the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the implementation methods, and do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it cannot be understood as limiting the scope of protection of the invention.

[0061] It should be noted that the use of words such as "first" and "second" to limit features is only for the convenience of distinguishing the corresponding features. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0062] It should also be noted that, in the description of this specification, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed connection, integral connection, or detachable connection; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this specification based on the specific circumstances.

[0063] The embodiments of this specification provide a molding device comprising a die, an inner mold core, and an outer mold. The inner mold core is fixed to the bottom of the outer mold, and an opening is provided at the top of the outer mold. A mold cavity adapted to the molded product is formed between the circumference of the inner mold core and the outer mold. The die is pressed down until it engages with the opening of the outer mold. The die, inner mold core, and outer mold jointly extrude the material into the molded product. The molded product is a hollow structure having an inner wall and an outer wall. The inner wall surface of the outer mold adapts to the shape of the outer wall of the molded product, and the outer surface of the inner mold core adapts to the shape of the inner wall of the molded product.

[0064] In some embodiments, the outer mold is a cylindrical structure with a bottom and an open top. The inner mold core is a columnar structure with a cross-section of square, circular, triangular, etc., and the inner mold core can also be a cylindrical structure without a top. The side of the die close to the outer mold is adapted to the opening of the outer mold. When the die is pressed down to connect with the opening of the outer mold, the die can cover the opening close to the outer mold, so that the die and the outer mold together form a sealed space. In some embodiments, at least part of the circumferential side of the die is adapted to the opening of the outer mold, and at least part of the circumferential side of the die is in contact with the opening of the outer mold, thereby achieving connection between the die and the outer mold. In some embodiments, the circumferential side of the die protrudes outward relative to the outer mold, and the side of the die close to the outer mold is in contact with the top of the outer mold, covering the opening of the outer mold, thereby achieving connection between the die and the outer mold.

[0065] Specifically, the material that can be extruded into a molded product is quantitatively filled into the mold cavity formed between the circumference of the inner mold core and the outer mold, and the material is initially formed within the constraints of the mold cavity. The die is pressed down until it connects with the opening of the outer mold, and the die, inner mold core, and outer mold jointly extrude the material to form it. During the extrusion process, the material does not involve large-scale flow, the extrusion force is uniform, and the resulting molded product has good structural uniformity, stable performance, and extended service life. Moreover, because the material does not require large-scale flow during the extrusion process, little or no friction is generated relative to the inner mold core and the outer mold, and the size and structure of the molded product are not restricted. However, when existing crucible manufacturing equipment is used to extrude a crucible, the crucible height exceeds 800 mm, which significantly reduces the quality of the crucible and shortens its service life, significantly affecting the cost of producing lithium batteries. However, under pressure constraints, the maximum height that existing crucible manufacturing equipment can extrude reaches 1200 mm. Sometimes, in order to solve the quality problem of the molded product, the wall thickness of the molded product is increased and / or the size of the molded product is reduced. However, when extruding using the molding device 100, the quality of the molded product is not affected by its wall thickness and size.

[0066] The forming device involved in this specification can be used not only to extrude carbon graphite crucibles, but also to extrude graphite crucibles, alloy parts, plastic parts and other hollow structural parts that can be extruded, such as silicon carbide protection tubes, refractory crucibles for high-temperature metal liquids, refractory guide tubes, and refractory material (such as silicon carbide, silicon nitride, etc. and various mixtures) protection tubes.

[0067] In some embodiments, the molding device can be used not only in the production of lithium batteries, but also in the manufacture of automobiles, aircraft, and sporting goods.

[0068] It should be noted that the use scenarios of the molding device described here are for illustrative purposes only and are not intended to be limiting. Based on the structure and operating principles of the molding device described in this specification, the molding device can be used in a wide range of work scenarios aimed at improving the quality of molded products, rather than being limited to the work scenarios listed in this specification. For ease of explanation, the following description, combined with the accompanying drawings, uses the molding device for extrusion production of crucibles as an example.

[0069] Figure 2 Schematic diagram of the structure of the forming device according to some embodiments. Figure 2 As shown, the embodiment of this specification proposes a molding device 100, which includes a die 110, an inner mold core 120, and an outer mold 130. The inner mold core 120 is fixed to the bottom of the outer mold 130. The top of the outer mold is provided with an opening. A mold cavity 140 adapted to the molded product is formed between the inner mold core 120 and the outer mold 130. The die 110 is pressed down until it is connected to the opening of the outer mold 130. The die 110, the inner mold core 120, and the outer mold 130 jointly extrude the material into a molded product. The molded product is a hollow structure having an inner wall and an outer wall. The inner wall surface of the outer mold 130 is adapted to the shape of the outer wall of the molded product, and the outer surface of the inner mold core 120 is adapted to the shape of the inner wall of the molded product.

[0070] In some embodiments, the outer mold 130 is a cylindrical structure, and its cross-sectional shape is circular, square, triangular, polygonal, gear-shaped, etc. In some embodiments, the outer mold 130 has a bottom, and an opening is set at the top of the outer mold 130. In some embodiments, the inner mold core 120 is a columnar structure, and its cross-sectional shape is circular or square, etc. In some embodiments, the inner mold core 120 is a cylindrical structure, and its cross-sectional shape is circular, square, triangular, polygonal, gear-shaped, honeycomb, grid-shaped, etc. It can have a top and a bottom, or only have a bottom or a top. The inner mold core 120 can also be a cylindrical structure with both ends passing through, that is, it has no bottom and top. When the molding device 100 is used for extrusion, the quality of the molded product is not affected by its shape. Existing crucible manufacturing equipment for extruding crucibles is generally only used for extruding round crucibles. For square crucibles, due to the fluidity problem of the material, the extrusion effect using existing crucible manufacturing equipment is even worse. However, the service life of a square crucible is longer than that of a round crucible of the same size, and its volume is larger. When a square crucible is extruded using the forming device 100, its furnace loading capacity can be increased by more than 25%. When producing the same amount of negative electrode material, the production cost of a square crucible extruded using the forming device 100 is reduced by more than 20%. Furthermore, the production of oversized crucibles for metal smelting, for example, crucibles with a diameter greater than 1.5 meters and a height greater than 2.5 meters, isostatic pressing is usually used to produce a solid body, which is then roasted and graphitized. However, due to the large volume required, cracking is easy to occur during roasting and graphitization, and the product quality is quite unsatisfactory. However, when using the forming device 100 involved in this specification to produce oversized crucibles for metal smelting, after testing, its forming performance basically meets the isostatic pressing requirements, the quality of the molded product is excellent, and the structural uniformity is good. It is not restricted by the size of the molded body, and the product quality can meet the requirements.

[0071] Figure 3 is a schematic diagram of the cross-sectional shape of the inner mold core according to some embodiments. Figure 4 1 is a schematic diagram of a cross-sectional shape of an inner mold core according to some other embodiments. In some embodiments, the cross-sectional shape of the inner mold core 120 includes a honeycomb shape. For example, Figure 3 As shown, the cross-sectional shape of the inner mold core 120 is a 9-hole circular honeycomb. In some other embodiments, the cross-sectional shape of the inner mold core 120 includes a grid shape or other special-shaped shapes. For example, Figure 4 As shown, the cross-section of the inner mold core 120 is a seven-hole grid. In some embodiments, the inner mold core 120 includes multiple sub-cores, allowing for the production of multiple molded products in a single molding process. In this case, the inner mold core 120 is a through-hole structure, meaning it lacks a bottom or top. Material can enter the inner mold core 120, for example, through the grid holes of the inner mold core 120, and is then extruded and molded by the die 110 or the die 110 and the flexible membrane 150 (described below).

[0072] Figure 5 is a schematic diagram of a cross-sectional shape of an inner mold core according to some embodiments; Figure 6 The inner mold core has Figure 5 Schematic diagram of the structure with the cross-sectional shape shown.

[0073] In some embodiments, as Figure 5 and Figure 6 As shown, the cross-section of inner mold core 120 is shaped like a square grid. Partitions are provided within inner mold core 120, dividing its cross-section into four sections. Inner mold core 120 is a through-end structure, meaning it lacks a bottom or top, allowing material to enter. The flexible membrane, described later, is positioned along inner mold core 120, including the internal partitioning surfaces, thereby enhancing the structural strength of inner mold core 120. Molded products produced using inner mold core 120 incorporate a built-in reinforced grid, which improves performance, particularly when the overall size of the molded product is large. This also further increases the effective volume within the molded product, reducing graphitization production costs.

[0074] Some embodiments of this specification can adapt to the requirements of the quantity, structure and shape of different molded products by changing the shape structure of the inner mold core 120, thereby increasing the effective volume inside the molded product.

[0075] In the application of graphite crucible molding, there are two existing methods for producing graphite crucibles. One is to make the graphite material into a solid block and then dig it into a crucible, with a material loss of up to 80%. The other method is to use equipment similar to the existing crucible manufacturing equipment to extrude it, which also has the problems of uneven structure and inconsistent density, and the quality is easily damaged during actual use.

[0076] In some embodiments, see Figure 2 The molding device 100 includes a flexible membrane 150, which is disposed over the outer surface of the inner mold core 120. The mold cavity 140 is located between the flexible membrane 150 and the outer mold 130. The flexible membrane 150 is sealed to the inner mold core 120, forming a pressurized cavity between the flexible membrane 150 and the inner mold core 120. By applying pressure to the pressurized cavity, the flexible membrane 150 uniformly squeezes the material toward the outer mold 130 and the pressure die 110. A mold cavity suitable for the molded product is formed between the flexible membrane 150, the outer mold 130, and the pressure die 110. The pressure die 110, the inner mold core 120, the flexible membrane 150, and the outer mold 130 jointly extrude the material to form the molded product. In some embodiments, the shape and structure of the flexible membrane 150 are compatible with the shape and structure of the inner mold core 120. In some embodiments, the flexible membrane 150 is made of expandable rubber or a composite rubber material (e.g., silicone rubber, fluororubber, nitrile rubber, natural rubber, etc.).

[0077] Figure 7Schematic diagram of the connection structure between the flexible film and the inner mold core according to some embodiments. Figure 7 Shown is Figure 2 A magnified view of the connection between the middle flexible membrane and the inner mold core.

[0078] In some embodiments, as Figure 7 As shown, the inner mold core 120 is fixed to the bottom of the outer mold 130, and the flexible film 150 wrapping the inner mold core 120 has an edge portion 151 close to the bottom of the outer mold 130. In order to maintain the uniformity of the pressurized cavity, the edge portion 151 of the flexible film 150 close to the bottom of the outer mold 130 is crimped between the inner mold core 120 and the outer mold 130. Specifically, the edge portion 151 of the flexible film 150 is crimped between the bottom of the inner mold core 120 and the bottom of the outer mold 130, so that the flexible film 150 is sealed and connected to the inner mold core 120.

[0079] In some embodiments, the flexible membrane 150 has a uniform elastic structure. When pressure is applied to the pressurized chamber, the flexible membrane 150 deforms under the pressure of the pressurized chamber. The flexible membrane 150 uniformly applies pressure to the material in the mold cavity 140, collaborating with the die 110 to extrude the material into a molded shape. In some embodiments, after the die 110 is lowered until it engages the outer mold 130, pressure is applied to the pressurized chamber. Under the pressure of the die 110, the flexible membrane 150 uniformly applies pressure to the material in the mold cavity 140.

[0080] In some embodiments, the molding device 100 includes a pressurizing member, which is used to pressurize the pressurizing chamber. In some embodiments, the pressurizing member introduces gas, liquid, or a gas-liquid mixture into the pressurizing chamber to achieve pressurization. For example, the gas includes air, inert gas, etc., and the liquid includes water, hydraulic oil, etc. In some embodiments, the pressurizing member has a preset pressure. After the pressurizing member pressurizes the pressurizing chamber to the preset pressure, the pressurizing member stops pressurizing to ensure the safety of the device operation and protect the structure of the molding device 100 and the molded product. In some embodiments, the pressurizing member includes a hydraulic pressurization system, a gas-liquid boost pressurization system, a servo electric pressurization system, etc.

[0081] There are various ways to apply pressure to the pressurized cavity, two of which are exemplified here. In some embodiments, the pressurized cavity is directly pressurized. By way of example only, a pressurized channel, such as a hydraulic pipe, is provided on the inner mold core 120. The pressurized channel communicates with the pressurized cavity, which is then connected to a pressurizing member. The pressurizing member then passes gas, liquid, or a gas-liquid mixture through the pressurized channel into the pressurized cavity, thereby pressurizing the pressurized cavity.

[0082] In some embodiments, the pressurization chamber is pressurized indirectly. Figure 2As shown, the inner mold core 120 is a hollow structure with a cavity. A through-hole 121 is provided on the inner mold core 120, extending through the sidewall of the inner mold core 120. The pressurized cavity communicates with the cavity of the inner mold core 120 through the through-hole 121. By applying pressure to the cavity of the inner mold core 120, the pressurized cavity is pressurized. In some embodiments, the inner mold core 120 is provided with multiple through-holes 121, evenly distributed throughout the inner mold core 120. The cavity of the inner mold core 120 acts as a buffer for the pressure in the pressurized cavity, maintaining a uniform pressure within the pressurized cavity, thereby allowing the flexible membrane 150 to uniformly apply pressure to the material from the outset. A pressurized channel 160 is provided on the inner mold core 120, and the pressurized channel 160 is connected to the pressurized component. The pressurized component passes the gas, liquid or gas-liquid mixture into the cavity of the inner mold core 120 through the pressurized channel, and then the gas, liquid or gas-liquid mixture enters the pressurized cavity through the through hole 121 on the inner mold core 120, thereby pressurizing the pressurized cavity.

[0083] In some embodiments, as Figure 7 As shown, the outer mold 130 includes a bottom mold 131 and a side mold 132. The bottom mold 131 is arranged at the bottom of the outer mold 130, and the inner mold core 120 is fixedly mounted on the bottom mold 131. The side mold 132 is a structure with two through ends. The first end of the side mold 132 is detachably connected to the circumference of the bottom mold 131, and the pressing mold 110 can cover the opening of the second end of the side mold 132. In some embodiments, the outer mold 130 includes a workpiece seat 1311, which is attached to the bottom mold 131 and arranged around the circumference of the inner mold core 120. The material in the mold cavity 140 contacts the workpiece seat 1311, which facilitates the demolding of the extruded material. After the material in the mold cavity 140 is extruded and molded, the pressure in the pressurized chamber is released, the side mold 132 is moved upward, the side mold 132 is separated from the bottom mold 131, and the workpiece seat 1311 is lifted to obtain a molded product.

[0084] In some embodiments, a boss is provided on the underside of the die 110, that is, the side close to the outer die 130, and the boss protrudes toward the outer die 130. When the underside of the die 110 is close to the outer die 130 and in contact with the outer die 130, the boss is used to embed into the interior of the outer die 130, that is, to extend into the die cavity 140, and squeeze the material in the die cavity 140.

[0085] In some embodiments, the molding apparatus includes support columns 170, to which the die 110 is movably connected. The support columns 170 are fixed. Driven by a first power member 180, the die 110 moves along the support columns 170 toward the outer die 130 to maintain stability during the engagement process between the die 110 and the outer die 130. In some embodiments, support columns 170 are vertically disposed on both sides of the outer die 130. In some embodiments, guide sleeves are disposed at corresponding ends of the die 110, forming a clearance fit with the support columns 170 to achieve a movable connection between the die 110 and the support columns 170.

[0086] In some embodiments, the first power member 180 drives the die 110 to move vertically. For example, the first power member 180 is a servo hydraulic cylinder or an electric ball screw mechanism. In some embodiments, the molding device 100 includes a fixed seat 181, which is used to fix the first power member 180, and the fixed seat 181 is fixed to the support column 170. In some embodiments, the molding device 100 includes a mechanical locking device, and the pressure between the die 110 and the outer mold 130 is not only provided by the first power member 180, but also provided by the mechanical locking device. In some embodiments, during the process of molding the product, the first power member 180 drives the side mold 132 to move upward, so that the side mold 132 is separated from the bottom mold 131, and the workpiece seat 1311 is lifted to obtain the molded product.

[0087] In some embodiments, the molding apparatus 100 includes a support base 190 for supporting the outer mold 130. In some embodiments, to facilitate the placement of a pressurizing element, when a pressurizing channel is provided on the inner mold core 120, the outer mold 130 and the support base 190 pass through the pressurizing channel, and the pressurizing channel passes through or connects to the pressurizing element to apply pressure to the pressurized cavity.

[0088] In some embodiments, the molding device 100 includes a stirring rod or a vibrating rod for evenly dispersing the material in the mold cavity 140. After the material is quantitatively filled into the mold cavity 140, the stirring rod or the vibrating rod is started, and the stirring rod or the vibrating rod penetrates into the material to assist in evenly filling the material, which is beneficial to ensure the uniform structure of the molded product.

[0089] In some embodiments, a heating assembly is provided at least one of the die 110, inner mold core 120, and outer mold 130. The heating assembly is used to heat the corresponding mold temperature, thereby heating the temperature of the material within the mold cavity 140, thereby facilitating stirring, mixing, and extrusion of the material. For example, a heating assembly is provided on each of the die 110, inner mold core 120, and outer mold 130, respectively, to heat the die temperatures of the die 110, inner mold core 120, and outer mold 130. In some embodiments, the heating assembly can be a heating assembly using water, oil, or the like as a heating medium, or an electric heating assembly using resistance heating as a medium.

[0090] In some embodiments, the material includes a dispersant to ensure uniform distribution within the mold cavity 140. Alloy powder, powdered, granular, or fibrous plastics can be extruded into sheet or tubular composite materials with the aid of a dispersant. This is then heat-treated and processed to create a highly elastic, highly flexurally resistant, and lightweight material. When the die 110 compresses and the flexible membrane 150 applies pressure, the dispersant is squeezed out of the material, requiring assistance in discharging the dispersant from the material.

[0091] Figure 8Schematic diagram of the configuration of an adsorption filter according to some embodiments.

[0092] In some embodiments, as Figure 8 As shown, the molding device 100 includes an adsorption filter 61 , which is arranged on the inner wall of the mold cavity 140 formed by the compression mold 110 and the outer mold 130 , that is, the adsorption filter 61 is located in the mold cavity 140 . Figure 8 The figure shows a local area between the die 110 and the inner mold core 120 in the molding device 100, and illustrates the arrangement of the adsorption filter 61 on the inner wall of the die 110. The arrangement of the adsorption filter 61 on the inner wall of the outer mold 130 is similar. When the die 110 and the flexible membrane 150 co-extrude the material, the adsorption filter 61 can adsorb and filter the dispersant contained in the material, helping the material to expel the dispersant. In some embodiments, the adsorption filter 61 is attached to the inner wall of the mold cavity 140 formed by the die 110 and the outer mold 130, and covers the entire inner wall of the die 110 and the outer mold 130, thereby increasing the adsorption and filtration area. The adsorption filter 61 can filter out liquid or gas components in the material during molding and pressurization. Multiple materials with different surface properties that are difficult to blend can be mixed evenly by using a third medium liquid or gas with dispersing properties (which does not affect the performance of the product). The materials are then placed into the mold cavity and then pressurized.

[0093] The embodiments of this specification also relate to a graphite product produced by the above-mentioned molding device 100. In some embodiments, the graphite product includes a graphite crucible, a graphite tube, and a graphite sagger. In some embodiments, the molding device 100 extrudes materials without being limited by the size of the graphite product. The molding device 100 can extrude graphite products of unconventional sizes, wherein the length of the graphite product is greater than or equal to 500 mm, the width of the graphite product is greater than or equal to 500 mm, and the height of the graphite product is greater than or equal to 800 mm. It is understood that the molding device 100 can of course extrude graphite products of conventional sizes.

[0094] In some embodiments, the bulk density difference of the graphite article as a whole is less than 0.02 g / cm 3 In some embodiments, the bulk density difference of the graphite article as a whole is less than 0.01 g / cm 3 , avoiding the formation of structural stratification caused by flow, effectively extending the service life of graphite products. Just as an example, the production of graphite crucibles with a length of 600mm, a width of 600mm, and a height of 1200mm, the quality data shows that the overall volume density difference of the graphite crucible is less than 0.01g / cm 3 , there will be no structural stratification caused by flow, and the service life of the graphite crucible is 5 to 6 times.

[0095] Existing because the restriction of forming equipment, graphite crucible overwhelming majority is circular crucible, graphitization production overwhelming majority adopts diameter size of 600mm, height dimension is the graphite crucible of 1200mm, wall thickness is at 35mm~40mm, and service life is about 4 times, and production cost is about 1400 yuan / individual (including lid), and in production, the space that occupies furnace interior volume is 600mm × 600mm × 1200mm, and its inside effective volume is 57.2%, and crucible height is limited, and 1200mm has reached the upper limit, if improve again, have a strong impact on service life. If use existing extrusion equipment to make square crucible, because the difficulty of extrusion molding, production yield rate is low, cost is high, quality is poor than circular crucible, and the wall thickness that finished product needs is big (about 60~80mm), and service life is 2~3 times.

[0096] When using the forming device 100 to produce a graphite crucible with dimensions of 600 mm in length, 600 mm in width, and 1200 mm in height, the crucible occupies a furnace volume of 600 × 600 × 1200 mm, with the effective volume of the crucible being 72.8%. The graphite crucible is not limited by the forming device 100 and can be made to approximately 1500 mm or even larger depending on the requirements of different graphitization furnaces, depending on the size of the forming device 100, without affecting the quality of the graphite crucible. The graphite crucible can have larger dimensions, for example, with dimensions of 1000 mm in length, 1000 mm in width, and 1200 mm in height. The overall cost of graphitization production is approximately 9,000 yuan per ton. Using the forming device 100, a graphite crucible can produce 1.25 tons of graphite negative electrode at a production cost of 9,000 yuan. Under the same production conditions, the production cost can be directly reduced to less than 7,200 yuan per ton. Currently, the annual production of negative electrode materials using round crucible graphitization is 2.5 million tons. However, the high-quality square crucibles manufactured using the forming device 100 have a longer service life and a longer number of uses, which greatly reduces production costs.

[0097] The embodiments of this specification also relate to a molded product, which is prepared by the above-mentioned molding device 100. In some embodiments, the molded product is extruded from at least one of coke powder, asphalt, graphite powder, alloy powder, powdered, granular or fibrous plastic. In some embodiments, the molding device 100 extrude the material without being restricted by the size of the molded product. The molding device 100 can extrude molded products of unconventional sizes, wherein the length of the molded product is greater than or equal to 500 mm, the width of the molded product is greater than or equal to 500 mm, and the height of the molded product is greater than or equal to 800 mm. It is understandable that the molding device 100 can of course extrude molded products of conventional sizes. In some embodiments, the overall volume density difference of the molded product is less than 0.02 g / cm 3In some embodiments, the bulk density difference of the molded article as a whole is less than 0.01 g / cm 3 , avoiding the formation of structural stratification caused by flow and effectively extending the service life of graphite products.

[0098] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of this specification. In addition, unless expressly stated in the claims, the order of elements and sequences, the use of alphanumeric characters, or the use of other names in this specification are not intended to limit the order of the processes and methods in this specification. Although some embodiments of the invention currently considered useful are discussed through various examples in the above disclosure, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that are consistent with the essence and scope of the embodiments of this specification.

Claims

1. A molding device, characterized in that: The forming device includes a pressing die, an inner mold core, an outer mold and a flexible film; The inner mold core is fixed to the bottom of the outer mold, the top of the outer mold is provided with an opening, and the pressing mold is pressed down until it is engaged with the opening of the outer mold; The flexible film is coated on the outer surface of the inner mold core, the flexible film is sealed with the inner mold core, a pressurized cavity is formed between the flexible film and the inner mold core, and a mold cavity adapted to the molded product is formed between the flexible film and the outer mold and the pressure mold; The compression mold, the inner mold core, the flexible film and the outer mold jointly extrude a material to form the molded product.

2. The molding device according to claim 1, characterized in that The inner mold core is a hollow structure with a cavity. A through hole is provided on the inner mold core. The pressurized cavity is connected to the cavity through the through hole. A pressurized channel for connecting to a pressurized part is provided on the inner mold core. The pressurized part is used to introduce gas, liquid or gas-liquid mixture into the pressurized cavity for pressurization. The cavity of the inner mold core is connected to the pressurized part through the pressurized channel.

3. The forming device according to claim 1 or 2, characterized in that: The flexible film is a uniform structure with elasticity, and the shape of the flexible film is adapted to the shape of the inner mold core.

4. The molding device according to claim 1 or 2, characterized in that: The edge portion of the flexible film covering the inner mold core is pressed tightly against the bottom of the inner mold core, thereby achieving a sealed connection between the flexible film and the inner mold core.

5. The forming device according to any one of claims 1 to 2, characterized in that: The outer shape of the inner mold core is consistent with the inner shape of the molded product.

6. The forming device according to any one of claims 1-2, characterized in that: The inner shape of the outer mold is consistent with the outer shape of the molded product.

7. The forming device according to any one of claims 1 to 2, characterized in that: The cross-sectional shape of the inner mold core includes at least one of a circular shape, a square shape, a honeycomb shape, a grid shape, a ring shape or a gear shape.

8. The forming device according to any one of claims 1-2, characterized in that: The outer mold includes a side mold and a bottom mold, the inner mold core is arranged on the bottom mold, the side mold is a structure with two ends through, the first end of the side mold is detachably connected to the peripheral side of the bottom mold, and the pressure mold can cover the opening of the second end of the side mold.

9. The molding device according to any one of claims 1-2, wherein a heating component is provided at least one of the pressing die, the inner mold core and the outer mold, and the heating component is used to heat the corresponding mold temperature.

10. The forming device according to any one of claims 1 to 2, characterized in that: The molding device includes a support column and a first power member. The die is movably connected to the support column. Driven by the first power member, the die moves away from or close to the outer die along the support column.

11. The forming device according to claim 10, characterized in that: The forming device includes a fixing seat, which is used to fix the first power member, and the fixing seat is fixed to the support column.

12. The forming device according to any one of claims 1-2, characterized in that: The forming device includes a support base, and the support base is used to support the outer mold.

13. The forming device according to any one of claims 1 to 2, characterized in that: The outer mold includes a side mold and a bottom mold, the inner mold core is arranged on the bottom mold, the side mold is a structure with two ends through, the first end of the side mold is detachably connected to the peripheral side of the bottom mold, and the pressure mold can cover the second end of the side mold; The forming device includes a support base, which is used to support the outer mold. The bottom mold is installed on the support base. A positioning structure is provided on the support base. The side mold is positioned and docked with the bottom mold through the positioning structure.

14. The forming device according to any one of claims 1 to 2, characterized in that: The material includes organic matter, inorganic matter or a mixture thereof, and the organic matter, inorganic matter or a mixture thereof includes coke powder, asphalt, graphite powder, alloy powder, powdered, granular or fibrous plastic or a combination thereof.

15. The forming device according to any one of claims 1-2, characterized in that: The material includes a dispersant, and the dispersant is used to make the material evenly distributed in the mold cavity; The molding device includes an adsorption filter screen, which is arranged on the inner wall of the mold cavity formed by the pressing mold and the outer mold. When the material is extruded, the adsorption filter screen is used to adsorb and filter the dispersant contained in the material.

16. The forming device according to claim 15, characterized in that Dispersants include, but are not limited to, water, alcohol, methanol, formaldehyde, benzene, toluene, and phenol.

17. A molding method, characterized in that: The molding method is applied to the molding device according to claim 1; the molding method comprises: Filling the material into the mold cavity; The pressing die is pressed down until it engages with the opening of the outer die; Under the pressure of the die, the die, the inner die core and the outer die jointly extrude the material into the molded product.

18. The molding method according to claim 17, characterized in that: The molding device includes a flexible membrane, the flexible membrane is coated on the outer surface of the inner mold core, the flexible membrane is sealed to the inner mold core, and a pressurized cavity is formed between the flexible membrane and the inner mold core; The molding method comprises: After the pressing die is pressed down to engage with the opening of the outer die, the pressure in the pressurizing cavity is increased to a desired pressure value. The pressure in the pressurizing cavity causes the flexible membrane to expand, squeezing the material in the die cavity into a molded product.

19. The molding method according to claim 18, characterized in that: The outer mold includes a side mold and a bottom mold, the inner mold core is arranged on the bottom mold, the side mold is a structure with two ends through, the first end of the side mold is detachably connected to the peripheral side of the bottom mold, and the pressure mold can cover the second end of the side mold; the molding method includes: After the material is extruded and formed, the pressure in the pressurized chamber is released, the side mold and the bottom mold are disassembled, and the side mold is removed to obtain the molded product.

20. A graphite product, characterized in that: Prepared by the molding device 7 according to claim 1, or prepared by the molding method according to claim 17, the graphite product includes a graphite crucible, a graphite tube, and a graphite sagger.

21. The graphite product according to claim 20, characterized in that The length of the graphite product is greater than or equal to 500 mm, the width of the graphite product is greater than or equal to 500 mm, and the height of the graphite product is greater than or equal to 800 mm.

22. The graphite product according to claim 20, wherein The bulk density difference of the graphite product as a whole is less than 0.02 g / cm 3 .

23. A molded product, characterized in that The molding device according to claim 1 or the molding method according to claim 17 is prepared by extrusion molding of at least one of an organic substance, an inorganic substance or a mixture thereof, and the organic substance, the inorganic substance or a mixture thereof includes coke powder, asphalt, graphite powder, alloy powder, powdered, granular or fibrous plastic.

24. The molded article according to claim 23, wherein The bulk density difference of the molded product as a whole is less than 0.02 g / cm 3 .

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