Floating type ultrahigh-pressure sealing device suitable for ultrahigh-pressure plunger pump

Abstract

The utility model discloses a floating type ultrahigh-pressure sealing device suitable for an ultrahigh-pressure plunger pump, relates to the technical field of ultrahigh-pressure plunger pump sealing, and aims to solve the problems that in the aspect of existing dynamic sealing performance, irreversible abrasion of a sealing ring is caused by friction between a shaft and a seal in high-pressure reciprocating motion, and the sealing performance is poor. According to the technical scheme, the plunger pump is characterized in that the plunger pump comprises a plunger pump body and a movable column body used for moving in the plunger pump body, and a sealing mechanism used for improving the ultrahigh pressure sealing effect is arranged between the movable column body and the plunger pump body; the sealing mechanism internally comprises a sealing plug body installed at the bottom of the movable column body, and the end, close to the movable column body, of the sealing mechanism is fixedly connected with an installation column. A combined sealing structure is adopted to fully seal the whole body, and friction loss can be automatically compensated to ensure that the whole body has a lasting and good sealing effect in a high-pressure state.

Description

Technical Field

[0001] This utility model relates to the technical field of ultra-high pressure plunger pump sealing, and in particular to a floating ultra-high pressure sealing device suitable for ultra-high pressure plunger pumps. Background Technology

[0002] Ultra-high pressure plunger seals (especially plenum seals) still face significant technical bottlenecks under extreme working conditions. Their core defects can be attributed to insufficient coordination in material properties, structural design, manufacturing processes, and verification systems.

[0003] First, in terms of materials, the main materials of the Pan-Se seal ring, such as polytetrafluoroethylene (PTFE) or ultra-high molecular weight polyethylene (UPE), are prone to plastic deformation due to creep characteristics under ultra-high pressure (>100MPa), and brittle fracture due to decreased toughness in low-temperature environments (such as -196℃). Second, the spring energy storage structure has the risk of failure. Stainless steel springs are prone to fatigue fracture under high pressure, and corrosive media will weaken their elastic compensation ability. The existing design does not fully consider the adaptation to nonlinear load distribution and extreme chemical environment.

[0004] In terms of manufacturing processes, turning and forming processes make it difficult to guarantee the uniformity of UPE filling and the accuracy of spring assembly. Local stress concentration and differences in the thermal expansion coefficients of interfaces (such as metal springs and non-metallic sealing shells) can cause micro-gap or delamination. In addition, finite element models are mostly based on static assumptions and do not accurately simulate the nonlinear constitutive relationship of materials under ultra-high pressure and the multi-physics coupling effect. The lack of long-term service data also makes life prediction dependent on experience. In terms of cost, high-performance materials (such as UPE) and customized springs drive up manufacturing costs, and the lack of standardized maintenance indicators leads to over-maintenance or unexpected downtime.

[0005] The existing technical solutions mentioned above also have the following defects: In terms of dynamic sealing performance, the lubricant is easily squeezed out during high-pressure reciprocating motion, which leads to increased dry friction and irreversible wear on the sealing lip. Furthermore, the unoptimized geometric design of the sealing lip (such as the mismatch between the chamfer radius and the pressure gradient) further exacerbates abnormal wear. At the same time, the lag in the dynamic response of the spring makes it difficult to adapt to sudden pressure changes, resulting in instantaneous leakage. Utility Model Content

[0006] The purpose of this invention is to provide a floating ultra-high pressure sealing device suitable for ultra-high pressure plunger pumps, which breaks through the structural limitations of traditional plunger seals that rely on spring energy storage.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A floating ultra-high pressure sealing device suitable for ultra-high pressure plunger pumps includes a plunger pump body and a movable column for moving inside the plunger pump body. A sealing mechanism for enhancing the ultra-high pressure sealing effect is provided between the movable column and the plunger pump body. The sealing mechanism includes a sealing plug installed at the bottom of the movable column. An installation column is fixedly connected to one end of the movable column. An installation hole for assembling the installation column is opened inside the movable column. A first sealing ring is clamped between the sealing plug and the movable column. A first sealing groove for installing the first sealing ring is reserved in the sealing plug and the movable column. A sealing ring is fixedly connected to the side of the first sealing ring away from the movable column.

[0009] By adopting the above technical solution, the first sealing ring, the sealing ring and the second support are combined to form the core component of the solid gradient composite sealing gasket. The nonlinear elastic modulus distribution design realizes the dynamic matching of sealing force and system pressure. That is, when the overall pressure is too high, the sealing structure realizes multi-end extrusion to achieve overall wall sealing, and even if it is worn under pressure, it can automatically compensate for the worn part.

[0010] Furthermore, the sealing ring is located outside the sealing plug body, and a pressing base is fixedly connected to the side of the sealing plug body away from the movable column. A second support is clamped between the pressing base and the sealing ring, and a second support groove for installing the second support is reserved between the pressing base and the sealing ring.

[0011] By adopting the above technical solution, the triple sealing structure of the first sealing ring, sealing ring and second support is achieved by the elastic deformation of micro-protrusions on the material surface to achieve initial sealing in the low pressure stage (<200MPa); in the medium and high pressure stage (200-800MPa), lattice slip is induced by matrix directional compression to generate radial expansion force to compensate for the sealing gap; in the ultra-high pressure stage (>800MPa), the topological interlocking effect of material particles is triggered to form a metal-like plastic flow wall seal.

[0012] Furthermore, a positioning button is movably connected inside the mounting column, and a limiting hole is opened inside the movable column that communicates with the inside of the mounting hole. The limiting hole is adapted to the shape and size of the positioning button.

[0013] By adopting the above technical solution, the positioning button can form a limiting and locking structure with the limiting hole, ensuring that the whole structure becomes a multi-level sealing structure, forming different degrees of sealing under different pressures.

[0014] Furthermore, the mounting column has a movable groove inside for the positioning button to move. A mounting spring is fixedly connected inside the movable groove. The side of the mounting spring away from the movable groove is fixedly connected to the positioning button. The positioning button is movably connected to the movable groove through the mounting spring. The positioning button has a frustum-shaped structure with a smooth outer surface.

[0015] By adopting the above technical solution, the positioning button with a smooth outer surface and a frustum-shaped structure can achieve positioning under no pressure and disengagement under high pressure, thus forming a three-level sealing effect.

[0016] Furthermore, the sealing rings are evenly distributed between the first sealing ring and the second support, and the inside of the sealing rings is fixedly connected to the outside of the sealing plug.

[0017] By adopting the above technical solutions, the sealing ring, the first sealing ring and the second support can achieve joint or individual sealing under different conditions, ensuring that the whole can still achieve full sealing under different pressures.

[0018] In summary, the beneficial technical effects of this utility model are as follows:

[0019] 1. The sealing gasket is made of modified polyetheretherketone (PEEK) / composite material or any other material with a Rockwell hardness greater than 10. Within the pressure range of 0-1000MPa, the material forms an elastic-plastic deformation synergistic response mechanism: in the low-pressure stage, the initial seal is achieved by the elastic deformation of the micro-protrusions on the material surface; in the medium and high pressure stages, the matrix directional compression induces lattice slip, generating radial expansion force to compensate for the sealing gap; in the ultra-high pressure stage, the topological interlocking effect of the material particles is triggered, forming a metal-like plastic flow wall seal.

[0020] 2. The sealing gasket adopts a multi-step topology with a gradually changing cross-section. Through finite element-assisted contact stress field reconstruction technology, the pressure distribution at the sealing interface and the inner wall of the plunger pump form a self-reinforcing wedge effect. Compared with traditional spring energy storage seals, the dynamic friction coefficient is controlled through a multi-material interface energy dissipation layer (such as a fluororubber / PTFE gradient composite layer). Under the condition of 1000MPa reciprocating motion, the friction power consumption is lower. In terms of installation and maintenance, a modular quick-release interface design is adopted. Combined with the shape memory recovery characteristics of the sealing gasket (recovery rate >98%), replacement can be completed within 5 minutes without special tools, which is more than 3 times more efficient than traditional plunger seals.

[0021] 3. A combined sealing structure is adopted to fully seal the whole, ensuring good sealing performance under high pressure. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0023] Figure 2 This is a schematic diagram of the front cross-section structure of this utility model;

[0024] Figure 3 This is a schematic diagram of the side cross-sectional structure of the present invention;

[0025] Figure 4 This is an enlarged structural schematic diagram of the sealing mechanism of this utility model.

[0026] In the diagram, 1. plunger pump body; 2. movable plunger; 3. sealing mechanism; 4. sealing plug; 5. mounting column; 6. mounting hole; 7. first sealing ring; 8. first sealing groove; 9. sealing ring; 10. clamping base; 11. second support; 12. second support groove; 13. positioning button; 14. limit hole; 15. movable groove; 16. mounting spring. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to the accompanying drawings.

[0028] Reference Figure 1 A floating ultra-high pressure sealing device suitable for ultra-high pressure plunger pumps includes a plunger pump body 1 and a movable column 2 for moving inside the plunger pump body 1. A sealing mechanism 3 for enhancing the ultra-high pressure sealing effect is provided between the movable column 2 and the plunger pump body 1. The sealing mechanism 3 includes a sealing plug 4 installed at the bottom of the movable column 2. A mounting column 5 is fixedly connected to one end near the movable column 2. An installation hole 6 for mounting the mounting column 5 is opened inside the movable column 2. A first sealing ring 7 is clamped between the sealing plug 4 and the movable column 2. A first sealing groove 8 for installing the first sealing ring 7 is reserved between the sealing plug 4 and the movable column 2. A sealing ring 9 is fixedly connected to the side of the first sealing ring 7 away from the movable column 2. The first sealing ring 7, the sealing ring 9, and the second support 11 form a triple sealing structure. The first sealing ring 7 and the second support 11 can change shape to ensure that the first sealing ring 7 and the second support 11 are fully and tightly sealed with the plunger pump body 1 and other components, ensuring a good overall sealing effect.

[0029] Reference Figure 2 The sealing ring 9 is located outside the sealing plug 4. The side of the sealing plug 4 away from the movable column 2 is fixedly connected to the pressing base 10. A second support 11 is clamped between the pressing base 10 and the sealing ring 9. A second support groove 12 is reserved between the pressing base 10 and the sealing ring 9 for the installation of the second support 11. The pressing base 10 can press the second support 11 to deform the second support 11, ensuring that the second support 11 is fully sealed and increasing the overall sealing effect.

[0030] Reference Figure 4The mounting column 5 is internally connected to a positioning button 13. The movable column 2 has a limiting hole 14 that communicates with the mounting hole 6. The limiting hole 14 is adapted to the shape and size of the positioning button 13. A part of the positioning button 13 is inserted into the limiting hole 14 to form a limiting structure, ensuring that the position of the mounting column 5 will not be significantly offset under normal conditions. The mounting column 5 has a movable groove 15 for the positioning button 13 to move. A mounting spring 16 is fixedly connected inside the movable groove 15. The side of the mounting spring 16 away from the movable groove 15 is fixedly connected to the positioning button 13. The positioning button 13 is movably connected to the movable groove 15 through the mounting spring 16. The positioning button 13 is a frustum-shaped structure with a smooth outer surface. The positioning button 13 with a smooth frustum-shaped structure can not only play a limiting role, but also retract into the movable groove 15 when the pressure is too high due to the force on the edge of the limiting hole 14, ensuring the normal movement of the mounting column 5.

[0031] Reference Figure 3 The sealing ring 9 is distributed in three sets at equal intervals between the first sealing ring 7 and the second support 11. The inside of the sealing ring 9 is fixedly connected to the outside of the sealing plug 4, forming a three-layer sealing structure to ensure a good overall sealing effect. The first sealing ring 7 is made of any material with a Rockwell hardness greater than 10, which can be plastic or metal. The second support 11 is made of any material with plasticity similar to fluororubber. Within the pressure range of 0-1000MPa, the material forms an elastic-plastic deformation coordinated response mechanism.

[0032] The implementation principle of this embodiment is as follows: During the overall sealing process, the movable column 2 is first subjected to pressure. In the low pressure stage (<200MPa), the initial sealing is achieved by the elastic deformation of the micro-protrusions on the material surface. That is, the sealing ring 9, the first sealing ring 7, and the second support 11 themselves form a sealing structure with the inner wall of the plunger pump body 1.

[0033] During the medium-high pressure stage (200-800MPa), lattice slip is induced by matrix directional compression, generating radial expansion force to compensate for the sealing gap. That is, the sealing plug 4 squeezes the first sealing ring 7 to fully fit the inner wall of the plunger pump body 1, forming a fully sealed structure.

[0034] In the ultra-high pressure stage >800MPa, the topological interlocking effect of the material particles is triggered, forming a metal-like plastic flow wall seal. That is, the pressing base 10 presses the second support 11 to compress the shape of the second support 11 from a ring to a shape that matches the changed second support groove 12, thereby ensuring a good overall seal.

[0035] Furthermore, when the whole is not under pressure, the positioning button 13 and the limiting hole 14 are inserted and positioned to form a limiting structure. When the movable column 2 is subjected to excessive pressure, the smooth-surfaced positioning button 13 will slowly move into the movable groove 15 under the pressure, so that the mounting column 5 can be displaced in the mounting hole 6, ensuring that the mounting column 5 can be displaced during the overall pressure change process.

[0036] The embodiments described herein are preferred embodiments of this utility model and are not intended to limit the scope of protection of this utility model. Therefore, all equivalent changes made to the structure, shape, and principle of this utility model should be included within the scope of protection of this utility model.

Claims

1. A floating ultra-high pressure sealing device suitable for ultra-high pressure plunger pumps, comprising a plunger pump body (1) and a movable column (2) for moving inside the plunger pump body (1), wherein a sealing mechanism (3) for increasing the ultra-high pressure sealing effect is provided between the movable column (2) and the plunger pump body (1), characterized in that: The sealing mechanism (3) includes a sealing plug (4) installed at the bottom of the movable column (2). A mounting column (5) is fixedly connected to one end of the movable column (2). The movable column (2) has an installation hole (6) for mounting the mounting column (5). A first sealing ring (7) is sandwiched between the sealing plug (4) and the movable column (2). A first sealing groove (8) for installing the first sealing ring (7) is reserved between the sealing plug (4) and the movable column (2). A sealing ring (9) is fixedly connected to the side of the first sealing ring (7) away from the movable column (2).

2. The floating ultra-high pressure sealing device for ultra-high pressure plunger pumps according to claim 1, characterized in that: The sealing ring (9) is located outside the sealing plug (4). The sealing plug (4) is fixedly connected to a pressing base (10) on the side away from the movable column (2). A second support (11) is clamped between the pressing base (10) and the sealing ring (9). A second support groove (12) for the installation of the second support (11) is reserved between the pressing base (10) and the sealing ring (9).

3. The floating ultra-high pressure sealing device for ultra-high pressure plunger pumps according to claim 1, characterized in that: The mounting column (5) is movably connected to a positioning button (13), and the movable column (2) is provided with a limiting hole (14) that communicates with the mounting hole (6). The limiting hole (14) is adapted to the shape and size of the positioning button (13).

4. The floating ultra-high pressure sealing device for ultra-high pressure plunger pumps according to claim 3, characterized in that: The mounting post (5) has an internal movable groove (15) for the positioning button (13) to move. An installation spring (16) is fixedly connected inside the movable groove (15). The side of the installation spring (16) away from the movable groove (15) is fixedly connected to the positioning button (13). The positioning button (13) is movably connected to the movable groove (15) through the installation spring (16). The positioning button (13) is a frustum-shaped structure with a smooth outer surface.

5. The floating ultra-high pressure sealing device for ultra-high pressure plunger pumps according to claim 1, characterized in that: The sealing rings (9) are evenly distributed between the first sealing ring (7) and the second support (11), and the inside of the sealing rings (9) is fixedly connected to the outside of the sealing plug (4).

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