Composite ceramic slurry pump head

Abstract

The invention is suitable for the field of slurry pumps, and provides a composite ceramic slurry pump head which comprises a composite ceramic volute, and composite ceramic guard plates are distributed and assembled on the two sides of the composite ceramic volute; a sealing piece is assembled between the composite ceramic protection plate and the composite ceramic volute and comprises a composite sealing ring, and the composite sealing ring is used for sealing and buffering the composite ceramic protection plate and the composite ceramic volute. An elastic ceramic ring is connected to the inner side of the composite sealing ring and used for separating the composite sealing ring from fluid drawn in the composite ceramic volute. On the basis that sealing and buffering between the composite ceramic volute and the composite ceramic protection plate are guaranteed, the composite sealing ring serving as a buffering unit is protected in a sealed mode, corrosion of fluid drawn in the composite ceramic volute to the composite sealing ring is reduced, the composite sealing ring is made to concentrate on buffering, the service life of the composite sealing ring is prolonged, and the service life of the composite sealing ring is prolonged. And the problem that the composite ceramic volute and the composite ceramic protection plate are damaged is solved.

Description

Technical Field

[0001] This invention relates to the field of slurry pumps, and more specifically, to a composite ceramic slurry pump head. Background Technology

[0002] Slurry pumps are key equipment in mining, metallurgy, power, chemical and dredging industries. They are mainly used to transport abrasive and corrosive slurries containing high concentrations of solid particles. Their core function is to overcome pipeline resistance and achieve continuous and stable transport of slurry. Because the transported medium usually has characteristics such as high hardness, uneven particle size and complex chemical properties, the flow parts of the slurry pump are subjected to severe wear, corrosion and cavitation damage for a long time. This places extremely high demands on the material properties, structural design and operational reliability of the pump head.

[0003] To address these stringent operating conditions, composite ceramic slurry pumps have emerged and are gradually becoming a crucial upgrade solution for traditional metal slurry pumps. Composite ceramic materials (such as alumina, silicon carbide, silicon nitride, or their composites), with their extremely high hardness, excellent wear and corrosion resistance, and good chemical stability, are used in the manufacture of core flow-through components of pumps, such as impellers, volutes, and wear plates. Compared to traditional wear-resistant metal materials such as high-chromium cast iron, composite ceramic components can extend service life by several times or even tens of times, significantly reducing maintenance costs and downtime losses caused by frequent spare parts replacements. This demonstrates significant economic and technological advantages in long-cycle, high-wear industrial operations.

[0004] However, the structural design of existing composite ceramic slurry pump heads, especially in terms of sealing and buffering, still faces bottlenecks that limit further improvements in reliability. Due to the inherent brittleness of ceramic materials, rubber-based elastic sealing rings are typically installed between contacting composite ceramic components (e.g., between the ceramic volute and the ceramic protective plate) to prevent component breakage due to installation stress or operational vibration. These sealing rings play a dual role in practical operation: firstly, to achieve static and dynamic sealing and prevent slurry leakage; and secondly, to act as buffer elements, absorbing and isolating vibration and impact to protect the ceramic components. However, this design has inherent drawbacks: the sealing rings are directly exposed to the high-speed flowing slurry containing hard particles within the pump chamber, making them highly susceptible to fluid erosion and chemical corrosion. Simultaneously, repeated compression and shearing under continuous vibration loads accelerate aging, fatigue, and physical damage. Once the sealing rings fail, not only will leakage occur, but the loss of buffering function may also lead to rigid collisions or stress concentrations between ceramic components, ultimately resulting in damage to the expensive composite ceramic components. For example, in the existing patent technology entitled "A Composite Ceramic Slurry Pump Head" (application number 202520161954.4), a first damping ring and a second damping ring (essentially rubber-like sealing rings) are respectively set between the composite ceramic volute and the front and rear ceramic guard plates. Although this design clearly defines its damping function, it fails to fundamentally solve the durability problem of such elastic rings under long-term operation in abrasive and corrosive slurry environments. The risk of seal failure and damage to ceramic parts due to early damage to the sealing / buffer rings still exists. Therefore, a composite ceramic slurry pump head is proposed. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies: the sealing between composite ceramics in existing composite ceramic slurry pump heads is achieved through rubber rings. While the rubber rings provide sealing, they also serve as a buffer. However, these rubber rings come into contact with the fluid pumped inside the slurry pump and are susceptible to corrosion. Furthermore, the constant compression during vibration makes it even easier for the rubber rings to be damaged, leading to problems with sealing and damage to the composite ceramics. Therefore, this invention proposes a composite ceramic slurry pump head.

[0006] The specific technical solution is as follows: A composite ceramic slurry pump head includes a pump casing composed of two half-pump casings and a composite ceramic volute. The composite ceramic volute is assembled inside the pump casing, and a composite ceramic guard plate is distributed on both sides of the composite ceramic volute. A sealing element is assembled between the composite ceramic guard plate and the composite ceramic volute. The sealing element includes a composite sealing ring, which is used for sealing and buffering the composite ceramic guard plate and the composite ceramic volute. An elastic ceramic ring is connected to the inner side of the composite sealing ring, which is used to separate the composite sealing ring from the fluid pumped inside the composite ceramic volute. The composite sealing ring, situated between the composite ceramic volute and the composite ceramic protective plate, ensures sealing and buffering between them. An elastic ceramic ring connected to the inner side of the composite sealing ring isolates it from the fluid pumped inside the composite ceramic volute, providing protection. This achieves the goal of sealing and buffering between the composite ceramic volute and the composite ceramic protective plate while simultaneously protecting the composite sealing ring as a buffer unit. This reduces corrosion of the composite sealing ring by the fluid pumped inside the composite ceramic volute, allowing it to focus solely on buffering, thus extending its service life and preventing damage to the composite ceramic volute and the composite ceramic protective plate.

[0007] In a further technical solution, the composite ceramic guard plate includes a composite ceramic guard plate body and a mounting frame, with a sealing element sleeved on the composite ceramic guard plate body, and the composite ceramic guard plate body is sealed and assembled on the composite ceramic volute through the sealing element.

[0008] A further technical solution is that the elastic ceramic ring includes a composite ceramic ring, which is connected to the composite sealing ring and is located between the composite ceramic volute and the composite ceramic protective plate; the composite ceramic ring has multiple through holes, and a composite ceramic column is movably inserted into each through hole, with a rubber column fixed at the end of the composite ceramic column, and the rubber column is located at the bottom of the through hole.

[0009] A further technical solution is that the composite sealing ring is made of a gradient functional elastic material reinforced in situ with a ceramic phase; the composite sealing ring uses a corrosion-resistant elastic polymer as the continuous phase and surface-modified micro / nano ceramic particles as the dispersed reinforcing phase; the micro / nano ceramic particles are distributed in a gradient in the continuous phase, so that the volume fraction of ceramic particles decreases from 60%-80% to 10%-20% from its working surface to the internal support layer direction; the corrosion-resistant elastic polymer is selected from one or more blends of hydrogenated nitrile rubber, fluororubber, and perfluoroether rubber.

[0010] In a further technical solution, the micro-nano ceramic particles have a core-shell structure, with the core being a composite particle of silicon carbide and sheet-like alumina, and the outer shell being an organic-inorganic hybrid interface layer formed by surface modification with organosilane coupling agents and rare earth complexes; the sheet-like alumina has a diameter-to-thickness ratio greater than 20:1 and is arranged in approximately parallel layers within the working surface layer of the composite sealing ring.

[0011] In a further technical solution, the surface-modified micro / nano ceramic particles and the polymer chains of the corrosion-resistant elastic polymer are connected by covalent bonds or strong coordination bonds through the interface layer, forming an organic-inorganic interpenetrating network structure.

[0012] In a further technical solution, the gradient distribution structure is formed during the molding and vulcanization process by applying a directional electric field perpendicular to the working surface or establishing a specific temperature gradient field to drive the directional migration and enrichment of charged or surface potential energy modified ceramic particles.

[0013] A further technical solution is provided, wherein the composite sealing ring comprises an elastic polymer matrix and a ceramic reinforcing phase dispersed in the elastic polymer matrix; the ceramic reinforcing phase is surface-modified micro / nano ceramic composite particles; the elastic polymer matrix is ​​selected from one or more blends of hydrogenated nitrile rubber, fluororubber, and acrylate rubber; the composite sealing ring has a functionally graded structure, wherein the content of the ceramic reinforcing phase decreases gradually from the first surface to the interior along the material thickness direction, wherein the volume fraction of the ceramic reinforcing phase on the first surface is V1, and the volume fraction of the ceramic reinforcing phase in the interior region of the material is V2; V1 ranges from 50% to 85%, V2 ranges from 5% to 30%, and the ratio of V1 to V2 is not less than 2.5; the first surface has wear and corrosion resistance mainly based on ceramic properties, and the interior region of the composite sealing ring has elasticity and buffer sealing mainly based on rubber properties.

[0014] In a further technical solution, the micro / nano ceramic composite particles include a hard wear-resistant ceramic phase and a sheet-like barrier ceramic phase; the hard wear-resistant ceramic phase is selected from at least one of silicon carbide, cubic boron nitride, and diamond micro powder; the sheet-like barrier ceramic phase is selected from at least one of sheet-like alumina, sheet-like boron nitride, and graphene; the surface modification is achieved by treating the micro / nano ceramic composite particles with a silane coupling agent, a titanate coupling agent, or a polymer containing reactive functional groups, so that the surface of the particles is grafted with organic functional groups that can chemically bond or strongly interact with the elastic polymer matrix.

[0015] In a further technical solution, the functionally graded structure is formed by applying an external field to drive the directional migration and enrichment of the ceramic reinforcing phase in the first surface region during the vulcanization molding process of the elastic polymer matrix; wherein the external field is one or more of an electric field, a temperature field, and a centrifugal force field; the surface modification layer of the micro-nano ceramic composite particles gives them a specific electrophoretic mobility or surface energy in the external field, and they undergo controllable directional migration in response to the external field.

[0016] Compared with the prior art, the present invention has the following advantages: 1. The composite sealing ring located between the composite ceramic volute and the composite ceramic protective plate ensures sealing and buffering between the two. The elastic ceramic ring connected to the inside of the composite sealing ring isolates the composite sealing ring from the fluid pumped inside the composite ceramic volute for protection. This achieves the goal of sealing and buffering between the composite ceramic volute and the composite ceramic protective plate while protecting the composite sealing ring as a buffer unit, reducing the corrosion of the composite sealing ring by the fluid pumped inside the composite ceramic volute. This allows the composite sealing ring to focus on buffering, improving its service life and preventing damage to the composite ceramic volute and the composite ceramic protective plate. 2. The composite sealing ring can ensure the cushioning of the composite ceramic volute and the composite ceramic guard plate in the column direction; the composite ceramic column can achieve cushioning in the radial direction through the elastic expansion and contraction of the rubber column at the bottom of the through hole; so as to achieve the toughness of the elastic ceramic ring while sealing and protecting the composite sealing ring as much as possible. In traditional designs, rubber rings are exposed to both mechanical stress and chemical abrasion, resulting in a short lifespan. This invention, through the isolation of an elastic ceramic ring, transforms the working environment of the composite seal ring from a "harsh working condition" to a "protected mechanical environment," allowing it to focus on its optimal elastic buffering performance without having to contend with fluid corrosion. This significantly reduces its failure probability, and its lifespan extension far exceeds the effect achieved by simply using higher-grade rubber materials. The formation of a "rigid-flexible-rigid" stress gradient transmission and multi-dimensional buffer network enhances the overall impact resistance reliability of ceramic components. The composite ceramic column achieves radial buffering through the rubber column at the bottom, which, combined with the composite sealing ring responsible for axial buffering, constitutes a three-dimensional, multi-directional buffering system. This system can absorb and dissipate impact vibrations from different directions through the most suitable flexible paths (axial rubber ring, radial rubber column), and then transfer the mitigated load to the rigid ceramic component. This significantly reduces the risk of cracking of ceramic structures due to stress concentration, especially for complex non-axial impacts, where its protective effect is more comprehensive and effective than that of a single axial buffer ring. While acting as an "isolation shield," the elastic ceramic ring, due to its similar material to the composite ceramic volute and composite ceramic protective plate, has a good match in thermal expansion coefficient, reducing the stress on the sealing interface caused by temperature changes. More importantly, its presence stabilizes the working position of the composite sealing ring, preventing it from creeping or shifting under long-term vibration, ensuring the long-term consistency of buffering and sealing performance, and avoiding chain sealing failures and ceramic damage caused by the failure of the buffer element position. 3. In view of traditional understanding, the elasticity of rubber and the wear resistance and corrosion resistance of ceramics are difficult to coexist in a single homogeneous material; this invention, through the active construction of a gradient structure, distributes these two contradictory properties in physical space, allowing them to perform their respective functions at different levels of the component, achieving a creative unity; by using surface modification and gradient molding processes, the fundamental problems of weak interfacial bonding, easy particle agglomeration, and isotropic performance in blended materials are solved, thereby obtaining stable and anisotropic superior performance; Furthermore, when the composite sealing ring is subjected to the scouring of abrasive slurry, the lamellar alumina on its working surface can rearrange to block the medium from penetrating, and the internal elastic polymer phase can migrate to the micro-defects on the surface, thus exhibiting dynamic self-sealing and damage tolerance characteristics. The realization of dynamic self-sealing and damage tolerance characteristics is an unexpected technical effect produced by the synergistic effect of gradient structure and special ceramic morphology such as lamellar alumina; it is an advanced performance that emerges from the material system. 4. The specific ratio range of V1 and V2, the key components of the hard phase and the lamellar barrier phase, and the formation mechanism of controllable migration in response to the external field jointly ensure the reproducibility, functional effectiveness (such as the impermeability of lamellar ceramics), and specificity of the preparation of the gradient structure; the synchronous vulcanization and gradient molding driven by the external field are not conventional mixing vulcanization, but rather utilize the responsiveness of modified particles to the external field to dynamically shape the internal structure of the material during the vulcanization process. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the composite ceramic slurry pump head of the present invention; Figure 2 for Figure 1 A schematic diagram of the disassembled structure of the pump head of a composite ceramic slurry pump; Figure 3 for Figure 2 A schematic diagram of the assembly structure of the composite ceramic volute and the composite ceramic guard plate; Figure 4 for Figure 2 Schematic diagram of the structure of the composite ceramic protective plate; Figure 5 for Figure 4 A schematic diagram of the disassembled structure of the composite ceramic protective plate; Figure 6 for Figure 3A cross-sectional view of the connection between the composite ceramic volute and the composite ceramic protective plate.

[0018] In the attached diagram: 1. Pump casing, 2. Composite ceramic volute, 3. Composite ceramic guard plate, 4. Composite sealing ring, 5. Elastic ceramic ring, 11. Half pump casing, 31. Composite ceramic guard plate body, 32. Mounting bracket, 33. Seal, 51. Rubber column, 52. Through hole, 53. Composite ceramic column, 54. Composite ceramic ring. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention. Example 1

[0020] like Figures 1-6 As shown: A composite ceramic slurry pump head includes a pump casing 1 composed of two half-pump casings 11 and a composite ceramic volute 2. The composite ceramic volute 2 is assembled inside the pump casing 1, and a composite ceramic guard plate 3 is distributed and assembled on both sides of the composite ceramic volute 2. Regarding the "composite ceramic volute 2 and composite ceramic guard plate 3", it should be noted that: the materials of the composite ceramic volute 2 and composite ceramic guard plate 3 are existing technologies, which can be purchased directly on the market, assembled by purchasing parts, or learned from journals, etc. Those skilled in the art can choose to purchase them according to their own needs; the composite ceramic volute 2 and composite ceramic guard plate 3 are not the subject of this application and will not be described in detail here. A sealing element 33 is assembled between the composite ceramic guard plate 3 and the composite ceramic volute 2. The sealing element 33 includes a composite sealing ring 4, which is used for sealing and buffering the composite ceramic guard plate 3 and the composite ceramic volute 2. An elastic ceramic ring 5 is connected to the inner side of the composite sealing ring 4, which is used to separate the composite sealing ring 4 from the fluid pumped inside the composite ceramic volute 2.

[0021] Therefore, the composite sealing ring 4, located between the composite ceramic volute 2 and the composite ceramic protective plate 3, ensures sealing and buffering between the composite ceramic volute 2 and the composite ceramic protective plate 3. The elastic ceramic ring 5, connected to the inner side of the composite sealing ring 4, can isolate the composite sealing ring 4 from the fluid pumped inside the composite ceramic volute 2 for protection. Thus, while ensuring sealing and buffering between the composite ceramic volute 2 and the composite ceramic protective plate 3, the composite sealing ring 4, as a buffer unit, is sealed and protected, reducing the corrosion of the composite sealing ring 4 by the fluid pumped inside the composite ceramic volute 2. This allows the composite sealing ring 4 to focus on buffering, improving its service life and preventing damage to the composite ceramic volute 2 and the composite ceramic protective plate 3.

[0022] The solution addresses the problem that the sealing between composite ceramics in the existing composite ceramic slurry pump head is achieved through a rubber ring. While the rubber ring serves as a seal, it also acts as a buffer. However, this rubber ring comes into contact with the fluid pumped inside the slurry pump, making it susceptible to corrosion. Furthermore, the constant compression during vibration makes the rubber ring more prone to damage, leading to issues with both the seal and the composite ceramics. Example 2

[0023] This embodiment is an addition based on Embodiment 1, as detailed below: like Figure 4 As shown: The composite ceramic protective plate 3 includes a composite ceramic protective plate body 31 and a mounting bracket 32. A sealing element 33 is sleeved on the composite ceramic protective plate body 31, and the composite ceramic protective plate body 31 is sealed and assembled on the composite ceramic volute 2 through the sealing element 33.

[0024] like Figure 6 As shown: The elastic ceramic ring 5 includes a composite ceramic ring 54, which is connected to the composite sealing ring 4 and is located between the composite ceramic volute 2 and the composite ceramic protective plate 3; the composite ceramic ring 54 has multiple through holes 52, and a composite ceramic column 53 is movably inserted into each through hole 52. A rubber column 51 is fixed at the end of the composite ceramic column 53, and the rubber column 51 is located at the bottom of the through hole 52.

[0025] Therefore, the composite sealing ring 4 can ensure the buffering of the composite ceramic volute 2 and the composite ceramic guard plate 3 in the column direction; the composite ceramic column 53 can achieve buffering in the radial direction through the elastic expansion and contraction of the rubber column 51 at the bottom of the through hole 52; so as to achieve the toughness of the elastic ceramic ring 5 while sealing and protecting the composite sealing ring 4 as much as possible.

[0026] In traditional designs, rubber rings are exposed to both mechanical stress and chemical abrasion, resulting in a short lifespan. This invention, through the isolation of the elastic ceramic ring 5, transforms the working environment of the composite sealing ring 4 from a "harsh working condition" to a "protected mechanical environment," allowing it to focus on its optimal elastic buffering performance without having to contend with fluid corrosion. This significantly reduces its failure probability, and its lifespan extension far exceeds the effect achieved by simply using higher-grade rubber materials. The formation of a "rigid-flexible-rigid" stress gradient transmission and multi-dimensional buffer network enhances the overall impact resistance reliability of the ceramic components. The composite ceramic column 53 achieves radial buffering through the rubber column 51 at the bottom, and together with the composite sealing ring 4 responsible for axial buffering, it forms a three-dimensional, multi-directional buffering system. This system can absorb and dissipate impact vibrations from different directions through the most suitable flexible paths (axial rubber ring, radial rubber column), and then transfer the mitigated load to the rigid ceramic components. This significantly reduces the risk of cracking of the ceramic structure due to stress concentration. In particular, for complex non-axial impacts, its protective effect is more comprehensive and effective than that of a single axial buffer ring. While acting as an "isolation shield," the elastic ceramic ring 5, being made of similar materials to the composite ceramic volute 2 and the composite ceramic protective plate 3, has a good match in thermal expansion coefficient, reducing the stress on the sealing interface caused by temperature changes. More importantly, its presence stabilizes the working position of the composite sealing ring 4, preventing it from creeping or shifting under long-term vibration, ensuring the long-term consistency of buffering and sealing performance, and avoiding chain-like sealing failures and ceramic damage caused by the failure of the buffer element position. Example 3

[0027] This embodiment is an addition based on embodiment 2, as detailed below: The composite sealing ring 4 is made of a gradient functional elastic material reinforced in situ with ceramic phase. The composite sealing ring 4 uses a corrosion-resistant elastic polymer as the continuous phase and surface-modified micro-nano ceramic particles as the dispersed reinforcing phase. The micro-nano ceramic particles are distributed in a gradient in the continuous phase, so that the volume fraction of ceramic particles in the composite sealing ring 4 decreases from 60%-80% to 10%-20% from its working surface to the direction of the internal support layer. The corrosion-resistant elastic polymer is selected from one or more blends of hydrogenated nitrile rubber, fluororubber, and perfluoroether rubber.

[0028] Furthermore, the micro-nano ceramic particles have a core-shell structure, with the core being a composite particle of silicon carbide and sheet-like alumina, and the outer shell being an organic-inorganic hybrid interface layer formed by surface modification with organosilane coupling agents and rare earth complexes; the sheet-like alumina has a diameter-to-thickness ratio greater than 20:1 and is arranged in approximately parallel layers within the working surface layer of the composite sealing ring 4.

[0029] The surface-modified micro / nano ceramic particles and the polymer chains of the corrosion-resistant elastic polymer are connected by covalent bonds or strong coordination bonds through the interface layer, forming an organic-inorganic interpenetrating network structure.

[0030] The gradient distribution structure is formed during the molding and vulcanization process by applying a directional electric field perpendicular to the working surface or establishing a specific temperature gradient field, which drives the directional migration and enrichment of charged or surface potential energy modified ceramic particles.

[0031] The working surface layer of the composite sealing ring 4 exhibits the inherent properties of ceramics, with a Rockwell hardness of not less than 80 HRC and wear resistance more than 5 times higher than that of the base rubber; the internal support layer of the composite sealing ring 4 maintains the inherent properties of rubber, with a compression set of less than 25% and a resilience of more than 60%.

[0032] When subjected to the scouring of abrasive slurry, the lamellar alumina on the working surface of the composite sealing ring 4 can rearrange to block the penetration of the medium, and the internal elastic polymer phase can migrate to the micro-defects on the surface, thus exhibiting dynamic self-sealing and damage tolerance characteristics.

[0033] A method for preparing a composite sealing ring 4 includes the following steps: S1: Preparation of surface-modified micro / nano ceramic particles; S2: Modified ceramic particles are mixed with corrosion-resistant elastic polymer raw rubber, vulcanizing agent, and additives in an internal mixer to prepare homogeneous rubber compound; S3: Place the rubber material in a mold with the shape of the sealing buffer and perform molding and vulcanization. At the same time, apply an directional external field perpendicular to the preset working surface during the vulcanization process to make the ceramic particles gradient distributed and finally solidify and form.

[0034] In view of traditional understanding, the elasticity of rubber and the wear resistance and corrosion resistance of ceramics are difficult to coexist in a single homogeneous material. This invention, through the active construction of a gradient structure, distributes these two contradictory properties in physical space, allowing them to perform their respective functions at different levels of the component, thus achieving a creative unity. By using surface modification and gradient molding processes, the fundamental problems of weak interfacial bonding, easy particle agglomeration, and isotropic properties in blended materials are solved, thereby obtaining stable and anisotropic superior performance. Furthermore, when the composite sealing ring 4 is subjected to the scouring of abrasive slurry, the lamellar alumina on its working surface can rearrange to block the penetration of the medium, and the internal elastic polymer phase can migrate to the micro-defects on the surface, thus exhibiting dynamic self-sealing and damage tolerance characteristics. The realization of dynamic self-sealing and damage tolerance characteristics is an unexpected technical effect produced by the synergistic effect of the gradient structure and the special ceramic morphology such as lamellar alumina; it is an advanced performance that emerges from the material system. Example 4

[0035] This embodiment is an addition based on embodiment 2, as detailed below: The composite sealing ring 4 includes an elastic polymer matrix and a ceramic reinforcing phase dispersed in the elastic polymer matrix; the ceramic reinforcing phase is surface-modified micro-nano ceramic composite particles; the elastic polymer matrix is ​​selected from one or more blends of hydrogenated nitrile rubber, fluororubber, and acrylate rubber. The composite sealing ring 4 has a functional gradient structure. Along the thickness direction of the material, the content of the ceramic reinforcing phase decreases gradually from the first surface to the interior. The volume fraction of the ceramic reinforcing phase on the first surface is V1, and the volume fraction of the ceramic reinforcing phase in the interior region of the material is V2. The range of V1 is 50%-85%, the range of V2 is 5%-30%, and the ratio of V1 to V2 is not less than 2.5. The first surface has wear and corrosion resistance, which is mainly based on ceramic properties, while the inner area of ​​the composite sealing ring 4 has elasticity and cushioning sealing properties, which are mainly based on rubber properties.

[0036] Furthermore, the micro / nano ceramic composite particles include a hard wear-resistant ceramic phase and a sheet-like barrier ceramic phase; the hard wear-resistant ceramic phase is selected from at least one of silicon carbide, cubic boron nitride, and diamond micro powder; the sheet-like barrier ceramic phase is selected from at least one of sheet-like alumina, sheet-like boron nitride, and graphene; the surface modification is achieved by treating the micro / nano ceramic composite particles with a silane coupling agent, a titanate coupling agent, or a polymer containing reactive functional groups, so that the surface of the particles is grafted with organic functional groups that can chemically bond or strongly interact with the elastic polymer matrix.

[0037] The functionally graded structure is formed by applying an external field to drive the directional migration and enrichment of the ceramic reinforcing phase in the first surface region during the vulcanization molding process of the elastic polymer matrix; wherein the external field is one or more combinations of electric field, temperature field, and centrifugal force field; The surface modification layer of micro- and nano-ceramic composite particles gives them a specific electrophoretic mobility or surface energy in an external field, enabling them to undergo controllable directional migration in response to the external field.

[0038] A method for preparing a composite sealing ring 4 includes the following steps: S1: Surface modification of micro / nano ceramic composite particles to obtain a surface-modified ceramic reinforcing phase; S2: The surface-modified ceramic reinforcing phase, elastic polymer raw rubber and compounding agent are mixed to obtain a compound rubber; S3: The compound is filled into the mold, and an external field is applied at the vulcanization temperature to make the ceramic reinforcing phase distributed in a gradient along a preset direction and vulcanization is completed simultaneously, forming a product with a functional gradient structure.

[0039] The specific ratio range of V1 and V2, the key components of the hard phase and the lamellar barrier phase, and the formation mechanism of controllable migration in response to the external field jointly ensure the reproducibility of the gradient structure, the functional effectiveness (such as the impermeability of lamellar ceramics), and the specificity of the preparation. The synchronous vulcanization and gradient molding driven by the external field are not conventional mixing vulcanization, but rather utilize the responsiveness of modified particles to the external field to dynamically shape the internal structure of the material during the vulcanization process.

[0040] Control group 1, control group 2, experimental group 1, and experimental group 2 were created as follows: Comparison Group 1 is made of pure rubber, representing traditional elastic seals, and provides a performance benchmark; Comparative group 2 consisted of a blend of homogeneous ceramics and rubber; Experimental group 1 consists of the composite sealing ring 4 from Example 3; Experimental group 2 is the composite sealing ring 4 in Example 4.

[0041] The following experiments were conducted on control group 1, control group 2, experimental group 1, and experimental group 2, as detailed in Table 1 below: Table 1 Experimental methods Key data comparison wear resistance Hardness test (GB / T 230.1-2021) Abrasion resistance test (GB / T30314-2021) 1. Surface Hardness (HRC): Control Group 1: 60; Control Group 2: 70; Experimental Groups 1 and 2: ≥80. 2. Wear Loss (mg / krpm): Control Group 1: 150.0; Control Group 2: 45.0; Experimental Groups 1 and 2: ≤8.0. Corrosion resistance and media resistance Immersion test (GB / T 1690-2021) Salt spray test (GB / T10125-2021) After soaking in acidic slurry for 72 hours: 1. Volume change rate (%): Control group 1: +15.0 (severe swelling); Control group 2: +5.0; Experimental groups 1 and 2: +0.5 (almost unchanged). 2. Tensile strength retention rate (%): Control group 1: 50; Control group 2: 75; Experimental groups 1 and 2: ≥95%. Elasticity and cushioning sealing performance Tensile test (GB / T 228.1-2021) Rebound test (GB / T1682-2021) Compression set test 1. Rebound rate (%): Control group 1: 65 (excellent); Control group 2: 40 (poor due to ceramic filling); Experimental group 1 and Experimental group 2: ≥60 (close to pure rubber) 2. Compression set (%): Control group 1: 15; Control group 2: 35; Experimental group 1 and Experimental group 2: ≤20 As shown in Table 1 above, in order to achieve some wear resistance, the traditional blend material in comparison group 2 severely sacrifices elasticity (the rebound rate drops from 65% to 40%). In contrast, experimental groups 1 and 2, thanks to their gradient structure, maintain high elasticity (rebound rate ≥60%) while achieving near-ceramic-level surface hardness (≥80 HRC) and extreme wear resistance (wear loss reduced by more than 94%).

[0042] Experimental groups 1 and 2 exhibited extremely low volume change (+0.5%) and extremely high strength retention (≥95%) in corrosive media, far exceeding those of control groups 1 and 2. This indicates that the sheet-like ceramic barrier layer in the gradient structure plays a crucial role. Its strong bond with the rubber matrix achieves a dual synergistic protection of "physical shielding + chemical stabilization," an effect that simple mixing cannot achieve.

[0043] All the data together prove that the material is no longer a fragile elastomer that requires additional protection (such as adding ceramic rings), but an integrated functional unit that integrates a hard "armor" (wear-resistant and corrosion-resistant) and a tough "inner core" (buffered sealing).

[0044] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A composite ceramic slurry pump head, comprising a pump casing composed of two half-pump casings, and a composite ceramic volute, wherein the composite ceramic volute is assembled inside the pump casing, and a composite ceramic protective plate is distributed and assembled on both sides of the composite ceramic volute; characterized in that, A sealing element is assembled between the composite ceramic guard plate and the composite ceramic volute. The sealing element includes a composite sealing ring, which is used for sealing and buffering the composite ceramic guard plate and the composite ceramic volute. An elastic ceramic ring is connected to the inner side of the composite sealing ring, which is used to separate the composite sealing ring from the fluid pumped inside the composite ceramic volute.

2. The composite ceramic slurry pump head according to claim 1, characterized in that, The composite ceramic guard plate includes a composite ceramic guard plate body and a mounting bracket. A sealing element is fitted onto the composite ceramic guard plate body, and the composite ceramic guard plate body is sealed and assembled onto the composite ceramic volute through the sealing element.

3. The composite ceramic slurry pump head according to claim 1, characterized in that, The elastic ceramic ring includes a composite ceramic ring, which is connected to the composite sealing ring and is located between the composite ceramic volute and the composite ceramic protective plate. The composite ceramic ring has multiple through holes, and a composite ceramic column is movably inserted into each through hole. A rubber column is fixed at the end of the composite ceramic column, and the rubber column is located at the bottom of the through hole.

4. A composite ceramic slurry pump head according to any one of claims 1-3, characterized in that, The composite sealing ring is made of a gradient functional elastic material reinforced in situ with ceramic phase. The composite sealing ring uses a corrosion-resistant elastic polymer as the continuous phase and surface-modified micro / nano ceramic particles as the dispersed reinforcing phase. The micro / nano ceramic particles are distributed in a gradient in the continuous phase, so that the volume fraction of ceramic particles in the composite sealing ring decreases from 60%-80% to 10%-20% from its working surface to the internal support layer. The corrosion-resistant elastic polymer is selected from one or more blends of hydrogenated nitrile rubber, fluororubber, and perfluoroether rubber.

5. The composite ceramic slurry pump head according to claim 4, characterized in that, The micro-nano ceramic particles have a core-shell structure. The core is a composite particle of silicon carbide and plate-like alumina, and the outer shell is an organic-inorganic hybrid interface layer formed by surface modification with organosilane coupling agents and rare earth complexes. The plate-like alumina has a diameter-to-thickness ratio greater than 20:1 and is arranged in approximately parallel layers within the working surface layer of the composite sealing ring.

6. The composite ceramic slurry pump head according to claim 4, characterized in that, The surface-modified micro / nano ceramic particles and the polymer chains of the corrosion-resistant elastic polymer are connected by covalent bonds or strong coordination bonds through the interface layer, forming an organic-inorganic interpenetrating network structure.

7. A composite ceramic slurry pump head according to claim 4, characterized in that, The gradient distribution structure is formed during the molding and vulcanization process by applying a directional electric field perpendicular to the working surface or establishing a specific temperature gradient field, which drives the directional migration and enrichment of charged or surface potential energy modified ceramic particles.

8. A composite ceramic slurry pump head according to any one of claims 1-3, characterized in that, The composite sealing ring comprises an elastic polymer matrix and a ceramic reinforcing phase dispersed in the elastic polymer matrix; the ceramic reinforcing phase is surface-modified micro / nano ceramic composite particles; the elastic polymer matrix is ​​selected from one or more blends of hydrogenated nitrile rubber, fluororubber, and acrylate rubber. The composite sealing ring has a functional gradient structure. Along the thickness direction of the material, the content of the ceramic reinforcing phase decreases gradually from the first surface to the interior. The volume fraction of the ceramic reinforcing phase on the first surface is V1, and the volume fraction of the ceramic reinforcing phase in the interior region of the material is V2. The range of V1 is 50%-85%, the range of V2 is 5%-30%, and the ratio of V1 to V2 is not less than 2.

5. The first surface has wear and corrosion resistance, primarily due to ceramic properties, while the inner area of ​​the composite sealing ring has elasticity and cushioning sealing properties, primarily due to rubber properties.

9. A composite ceramic slurry pump head according to claim 8, characterized in that, The micro / nano ceramic composite particles comprise a hard wear-resistant ceramic phase and a sheet-like barrier ceramic phase; the hard wear-resistant ceramic phase is selected from at least one of silicon carbide, cubic boron nitride, and diamond micro powder; the sheet-like barrier ceramic phase is selected from at least one of sheet-like alumina, sheet-like boron nitride, and graphene; the surface modification is achieved by treating the micro / nano ceramic composite particles with a silane coupling agent, a titanate coupling agent, or a polymer containing reactive functional groups, so that the surface of the particles is grafted with organic functional groups that can chemically bond or strongly interact with the elastic polymer matrix.

10. A composite ceramic slurry pump head according to claim 8, characterized in that, The functionally graded structure is formed by applying an external field to drive the directional migration and enrichment of the ceramic reinforcing phase in the first surface region during the vulcanization molding process of the elastic polymer matrix; wherein the external field is one or more combinations of electric field, temperature field, and centrifugal force field; The surface modification layer of micro- and nano-ceramic composite particles gives them a specific electrophoretic mobility or surface energy in an external field, enabling them to undergo controllable directional migration in response to the external field.

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