Non-contact end face sealing assembly and high-speed pump

Abstract

This utility model relates to the field of mechanical seal technology, providing a non-contact end-face sealing assembly and a high-speed pump. The sealing assembly includes a stationary ring and a rotating ring, which are spaced apart and opposite to each other. The end face opposite to the stationary ring forms a sealing end face. The downstream region of the sealing end face near the center of the stationary or rotating ring is a low-pressure region, which has interconnected sub-millimeter-level annular grooves and micrometer-level annular grooves. The two sides of the micrometer-level annular grooves form a sealing dam area. The upstream region of the sealing end face away from the center of the stationary or rotating ring is a high-pressure region, which has multiple spiral groove groups arranged periodically along the circumference. Each spiral groove group includes interconnected sub-millimeter-level spiral grooves and micrometer-level spiral grooves. The non-groove area between two adjacent spiral groove groups forms a sealing weir area. This utility model, by setting composite spiral grooves and annular grooves on the sealing end face, reconstructs the flow field and temperature field distribution on the end face, which can significantly improve the heat transfer conditions on the end face and effectively suppress the fluid film temperature rise.

Description

Technical Field

[0001] This utility model relates to the field of mechanical seal technology, and in particular to a non-contact end face sealing assembly and a high-speed pump. Background Technology

[0002] Non-contact end-face sealing assemblies are key components of high-speed pumps in aerospace and other fields. They effectively prevent high-pressure fluid leakage along the rotating shaft, ensuring the safe and stable operation of the equipment. During sealing operation, the high-pressure fluid in the sealing cavity is directionally injected into the sealing end-face gap under the coupled driving force of the high-speed rotation of the rotating ring and the pressure difference between the inner and outer diameters of the sealing ring. When the fluid enters this micro-gap, through the synergistic effect of multiple fluid dynamic mechanisms such as hydrodynamic and hydrostatic effects, a stable micron-level hydrodynamic lubricating film can be built between the end faces of the rotating and stationary rings, enabling the friction pair to achieve a completely non-contact operating state, ultimately achieving the goal of sealed operation.

[0003] However, under high-speed operating conditions (especially in high-speed applications of pumps), the lubricating fluid within the end-face gap generates a large amount of viscous heat loss due to the intense shearing action of the moving ring. Traditional hydrodynamic mechanical seals often employ a micron-level shallow groove structure, which is prone to causing severe viscous heat generation in the fluid film during high-speed operation. This heat generation effect intensifies significantly with increasing rotational speed. Especially for high-viscosity media, the fluid within the gap is more susceptible to vaporization due to localized high temperatures, leading to disruption of fluid film stability and affecting sealing performance. Utility Model Content

[0004] This invention provides a non-contact end-face sealing assembly and a high-speed pump to solve the above-mentioned technical defects in the prior art. By setting a composite spiral groove and annular groove on the sealing end face, the flow field and temperature field distribution on the end face are reconstructed, which can significantly improve the heat exchange conditions on the end face, effectively suppress the temperature rise of the fluid film, and realize the reliable, safe and long-life operation of the non-contact end-face sealing assembly.

[0005] The first aspect of this utility model provides a non-contact end-face sealing assembly, comprising:

[0006] Static ring;

[0007] A rotating ring is spaced apart from and opposite to the stationary ring, and its end face opposite to the stationary ring forms a sealing end face. The downstream region of the sealing end face near the center of the stationary ring or the rotating ring is a low-pressure region. The low-pressure region has interconnected sub-millimeter-level annular grooves and micrometer-level annular grooves. The two sides of the micrometer-level annular grooves form a sealing dam area. The upstream region of the sealing end face away from the center of the stationary ring or the rotating ring is a high-pressure region. The high-pressure region has multiple spiral groove groups arranged periodically along the circumference. Each spiral groove group includes interconnected sub-millimeter-level spiral grooves and micrometer-level spiral grooves. The non-groove area between two adjacent spiral groove groups forms a sealing weir area.

[0008] According to the non-contact end-face sealing assembly provided by this utility model, the micron-level annular groove is located on both sides of the sub-millimeter-level annular groove;

[0009] The submillimeter-level annular groove and the micrometer-level annular groove located on both sides of the submillimeter-level annular groove are respectively opened on three virtual circles with different radii centered on the same center, and the center of the circle is located on the axial center line of the sealing end face.

[0010] According to the non-contact end-face sealing assembly provided by this utility model, both the sub-millimeter-level spiral groove and the micrometer-level spiral groove extend radially spirally to the outer wall of the moving ring or the stationary ring, and the micrometer-level spiral groove forms a three-sided surrounding structure of the sub-millimeter-level spiral groove in the circumferential direction.

[0011] According to the non-contact end-face sealing assembly provided by this utility model, the depth of the micron-level spiral groove is H1, wherein the value of H1 ranges from 3μm to 30μm; the depth of the sub-millimeter-level spiral groove is H2, wherein the value of H2 ranges from 100μm to 1000μm.

[0012] According to the non-contact end-face sealing assembly provided by this utility model, the depth of the micron-level annular groove is H3, wherein the value of H3 ranges from 3μm to 30μm; the depth of the sub-millimeter-level annular groove is H4, wherein the value of H4 ranges from 100μm to 1000μm.

[0013] According to the non-contact end-face sealing assembly provided by this utility model, the helix angle of the micron-level spiral groove is α, wherein the value range of α is 12°~24°;

[0014] The width range of the micron-level spiral groove is 3mm to 30mm;

[0015] The radial length of the micron-sized spiral groove is 30% to 80% of the diameter of the sealing end face;

[0016] The number of micron-level spiral grooves on the sealing end face is 6 to 24.

[0017] According to the non-contact end-face sealing assembly provided by this utility model, the helix angle of the submillimeter-level spiral groove is equal to the helix angle of the micrometer-level spiral groove, and the number of the submillimeter-level spiral groove is equal to the number of the micrometer-level spiral groove;

[0018] The width range of the sub-millimeter spiral groove is 1mm to 10mm;

[0019] The radial length of the sub-millimeter-level spiral groove is 20% to 70% of the diameter of the sealing end face.

[0020] According to the non-contact end-face sealing assembly provided by this utility model, the distance between the micron-level annular groove and the inner wall of the moving ring or the stationary ring ranges from 1mm to 4mm; the width of the micron-level annular groove ranges from 2mm to 5mm.

[0021] According to the non-contact end-face sealing assembly provided by this utility model, the distance between the sub-millimeter annular groove and the inner wall of the moving ring or the stationary ring is in the range of 2mm~3mm; the width of the sub-millimeter annular groove is in the range of 1mm~4mm.

[0022] A second aspect of this utility model provides a high-speed pump, including a housing and a non-contact end-face sealing assembly as described in any one of the claims, wherein the non-contact end-face sealing assembly is disposed within the housing.

[0023] The non-contact end-face sealing assembly provided by this utility model employs a graded design of sub-millimeter and micron-level spiral grooves in the upstream high-pressure region. The deeper sub-millimeter spiral grooves expand the cold fluid inlet channel, allowing more cold fluid to be quickly injected into the sealing gap between the dynamic and stationary rings, facilitating sufficient heat exchange with the friction pair. This effectively prevents liquid film vaporization and thermal deformation of the sealing end face, ensuring sealing stability. Simultaneously, the deeper sub-millimeter spiral grooves increase the average thickness of the lubricating fluid film, reducing the viscous shear effect of the lubricating fluid film and thus decreasing the generation of viscous heat loss.

[0024] Because the depth of submillimeter-level spiral grooves is much greater than that of micrometer-level spiral grooves, when fluid enters from the submillimeter-level spiral grooves into the micrometer-level spiral grooves, the film thickness drops abruptly from the large film thickness of the submillimeter-level spiral grooves to the small film thickness of the micrometer-level spiral grooves. This causes a dramatic change in the velocity gradient at the groove boundary, thereby reducing the area of ​​the high-shear region. Simultaneously, the submillimeter-level spiral grooves retain some of the dynamic pressure effect of the micrometer-level spiral grooves, creating a local high-pressure zone at the groove root (the starting position of the micrometer-level spiral groove), providing additional opening force. Through this composite design of "deep grooves for strong heat transfer and shallow grooves for maintaining dynamic pressure," viscous heat generation is reduced, while simultaneously improving the bearing capacity and operational stability of the friction pair, and extending the seal life.

[0025] Furthermore, by combining submillimeter-level and micrometer-level annular grooves in the downstream low-pressure area, the leakage path is extended and the pressure gradient is reduced. The submillimeter-level annular groove, as the main leakage channel, has a larger groove width and depth, which requires the leaking fluid to take a longer radial path. At the same time, the interconnected design of the micrometer-level and submillimeter-level annular grooves forms a buffer cavity within the annular groove, further reducing the pressure gradient at the end of the leakage path and meeting the leakage control requirements of most industrial scenarios.

[0026] Therefore, the non-contact end-face sealing assembly provided by this utility model embodiment achieves reliable, safe and long-life operation of the non-contact end-face sealing assembly through the synergistic effect of improving heat exchange, reducing heat generation and controlling leakage.

[0027] The high-speed pump provided by this utility model has all the above advantages because it includes the aforementioned non-contact end-face sealing assembly. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is an exploded view of the structure of the non-contact end-face sealing assembly provided in this embodiment of the utility model.

[0030] Figure 2 This is a front view of the non-contact end-face sealing assembly provided in this embodiment of the utility model.

[0031] Figure 3 This is an isometric sectional view of the non-contact end-face sealing assembly provided in this embodiment of the utility model.

[0032] Figure 4 This is a cross-sectional view of the non-contact end-face sealing assembly provided in this embodiment of the utility model.

[0033] Figure label:

[0034] 10. Static ring;

[0035] 20. Moving ring; 21. Submillimeter-level annular groove; 22. Micrometer-level annular groove; 23. Spiral groove assembly; 231. Submillimeter-level spiral groove; 232. Micrometer-level spiral groove; 30. Fluid membrane;

[0036] D. Sealed dam area; W. Sealed weir area. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0038] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0039] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0040] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0041] Figure 1 This is an exploded view of the structure of the non-contact end-face sealing assembly provided in this embodiment of the utility model. Figure 2 This is a front view of the non-contact end-face sealing assembly provided in this embodiment of the utility model.

[0042] See Figure 1 and Figure 2 This utility model provides a non-contact end face sealing assembly, the structure of which includes a stationary ring 10 and a rotating ring 20.

[0043] The rotating ring 20 and the stationary ring 10 are spaced apart and opposite to each other, and the end face opposite to the stationary ring 10 constitutes a sealing end face. The downstream region of the sealing end face near the center of the stationary ring 10 or the rotating ring 20 is a low-pressure region, that is, the inner side of the sealing end face near the rotating ring 20 or the stationary ring 10, i.e., the direction of the axial center is the low-pressure region. The low-pressure region is provided with interconnected sub-millimeter-level annular grooves 21 and micrometer-level annular grooves 22. The two sides of the micrometer-level annular grooves 22 constitute a sealing dam area D. The sealing dam area D can be understood as the transition area between the micrometer-level annular grooves 22 and the edge of the sealing end face. The sealing dam area D is used to enhance the stability of the fluid film 30 in the low-pressure region.

[0044] The upstream region of the sealing end face away from the center of the stationary ring 10 or the rotating ring 20 is the high-pressure region, that is, the region near the outer side of the rotating ring 20 or the stationary ring 10, i.e., the circumferential direction is the high-pressure region. Multiple spiral groove groups 23 are periodically arranged circumferentially within the high-pressure region. Each spiral groove group 23 includes interconnected sub-millimeter-level spiral grooves 231 and micrometer-level spiral grooves 232. The root of the micrometer-level spiral groove 232 connects to the top of the sub-millimeter-level spiral groove 231, forming primary and secondary graded flow channels. The non-groove area between two adjacent spiral groove groups 23 constitutes the sealing weir area W, that is, the annular area not covered by the spiral groove group 23 constitutes the sealing weir area W. The sealing weir area W is used to balance fluid pressure and limit leakage.

[0045] Essentially, the composite spiral groove located upstream of the sealing end face, through the high flow rate introduction of the sub-millimeter-level spiral groove 231 and the dynamic pressure effect of the micron-level spiral groove 232 (low pressure at the top of the groove, high pressure at the root of the groove), forms a positive circulation of fluid injection and pressurization in the high-pressure region. Meanwhile, the composite annular groove in the low-pressure region and the sealing dam area D collect the fluid through the composite annular groove, and the sealing dam area D buffers and stabilizes the flow, making the pressure distribution of the fluid axially (from the high-pressure region to the low-pressure region) on the inner diameter side of the sealing ring more uniform, thus controlling the sealing leakage rate.

[0046] Under high-speed conditions, the fluid within the gap at the sealing end face is prone to turbulence due to the rotational shearing of the rotating ring 20. The spiral channels of the upstream composite spiral groove (submillimeter-level spiral groove 231 as the main channel and micron-level spiral groove 232 as the support channel) apply a circumferential rotational force to the fluid, causing it to flow directionally along the spiral groove and reducing radial disorder disturbance. The sealing dam area D performs secondary rectification of the fluid, reducing the radial velocity component of the fluid, allowing the fluid in the low-pressure area to enter the dam area in a more stable state, reducing turbulence intensity, and improving film thickness uniformity. At the same time, the annular groove near the inner diameter side can cut off the high-pressure area generated by the spiral groove and uniformize the fluid pressure on the inner diameter side, reducing the pressure gradient on the inner diameter side, thereby controlling leakage.

[0047] When the non-contact end-face sealing assembly provided by this utility model is applied to the sealing cavity of a high-speed pump, the high-pressure fluid (low temperature, usually room temperature or slightly higher than ambient temperature) in the sealing cavity, driven by the high-speed rotation of the rotating ring 20, preferentially enters the sealing end-face gap through the sub-millimeter spiral groove 231 in the upstream high-pressure region. The depth of the sub-millimeter spiral groove 231 is increased compared to the depth of the micrometer spiral groove 232, allowing more cold fluid to be injected into the gap of the sealing end face quickly, accelerating the heat exchange of the sealing end face, while also increasing the average thickness of the lubricating film, reducing the fluid viscous shear effect, and thus lowering the temperature of the sealing end face.

[0048] It should be noted that the submillimeter-level annular groove 21 and the micrometer-level annular groove 22, as well as the submillimeter-level spiral groove 231 and the micrometer-level spiral groove 232, can all be provided on the moving ring 20 or on the stationary ring 10. Alternatively, the submillimeter-level annular groove 21 and the micrometer-level annular groove 22 can be provided on one of the moving ring 20 and the stationary ring 10, and the submillimeter-level spiral groove 231 and the micrometer-level spiral groove 232 can be provided on the other of the moving ring 20 and the stationary ring 10.

[0049] It is understood that the non-contact end-face sealing assembly provided in this embodiment of the invention employs a graded design of sub-millimeter-level spiral grooves 231 and micrometer-level spiral grooves 232 in the upstream high-pressure region. The deeper sub-millimeter-level spiral grooves 231 expand the inlet channel for cold fluid, allowing more cold fluid to be quickly injected into the sealing gap between the moving ring 20 and the stationary ring 10, facilitating sufficient heat exchange with the friction pair. This effectively prevents liquid film vaporization and thermal deformation of the sealing end face, ensuring the stability of the seal. Simultaneously, the deeper sub-millimeter-level spiral grooves 231 increase the thickness of the lubricating fluid film, reducing the heat loss due to the viscosity of the lubricating fluid film.

[0050] Because the depth of the submillimeter-level spiral groove 231 is much greater than that of the micrometer-level spiral groove 232, when the fluid enters the micrometer-level spiral groove 232 from the submillimeter-level spiral groove 231, the film thickness drops sharply from the large film thickness of the submillimeter-level spiral groove 231 to the small film thickness of the micrometer-level spiral groove 232. This causes a dramatic change in the velocity gradient at the groove boundary, thereby reducing the area of ​​the high-shear region. Simultaneously, the submillimeter-level spiral groove 231 retains some of the dynamic pressure effect of the micrometer-level spiral groove 232, which can form a local high-pressure zone at the groove root (the starting position of the micrometer-level spiral groove 232), providing additional opening force. Through this composite design of "deep groove for strong heat transfer and shallow groove for maintaining dynamic pressure," the viscous heat generation is reduced, while the bearing capacity and operational stability of the friction pair are improved, extending the seal life.

[0051] Furthermore, by combining the submillimeter-level annular groove 21 and the micrometer-level annular groove 22 in the downstream low-pressure area, the leakage path is extended and the pressure gradient is reduced. The submillimeter-level annular groove 21 serves as the main leakage channel, and its larger groove width and depth require the leaking fluid to take a longer radial path. At the same time, the interconnected design of the micrometer-level annular groove 22 and the submillimeter-level annular groove 21 forms a buffer cavity within the annular groove, further reducing the pressure gradient at the end of the leakage path and meeting the leakage control requirements of most industrial scenarios.

[0052] Therefore, the non-contact end-face sealing assembly provided by this utility model embodiment achieves reliable, safe and long-life operation of the non-contact end-face sealing assembly through the synergistic effect of improving heat exchange, reducing heat generation and controlling leakage.

[0053] Figure 3 This is an isometric sectional view of the non-contact end-face sealing assembly provided in this embodiment of the utility model.

[0054] Continue reading Figure 2 And see also Figure 3 In some embodiments of this utility model, the micron-level annular groove 22 is located on both sides of the submillimeter-level annular groove 21; the submillimeter-level annular groove 21 and the micron-level annular groove 22 located on both sides of the submillimeter-level annular groove 21 are respectively opened on three virtual circles with different radii centered on the same center, and the center of the circle is located on the axial center line of the sealing end face.

[0055] Essentially, the sub-millimeter-level annular groove 21 and the micrometer-level annular groove 22 adopt a concentric circle and radially graded (different radii) layout design. Through radial symmetry and gradient distribution characteristics, precise control of the flow field at the sealed end face and multi-dimensional performance optimization are achieved, as detailed below:

[0056] Since the sealing end face serves as the contact interface for high-speed rotating components, the uniformity of fluid flow directly affects the sealing stability. If the groove position is offset, it can easily lead to uneven radial distribution of fluid, which can easily cause local pressure fluctuations or even jetting phenomena, i.e., high-speed fluid impacting the end face causing vibration.

[0057] This utility model embodiment uses a concentric design to ensure that the openings of the sub-millimeter and micrometer-level annular grooves 22 are strictly symmetrically distributed along the circumference. After the fluid enters the gap of the sealing end face from the sealing cavity, it can be evenly distributed radially into the three annular grooves, reducing the circumferential pressure deviation of the sealing end face, making the fluid flow more stable, and reducing the vibration of the sealing end face caused by pressure fluctuations.

[0058] Furthermore, the different radius designs (i.e. radial gradation) of the submillimeter-level annular groove 21 and the micrometer-level annular groove 22, and the composite annular groove with the shape of the submillimeter-level annular groove 21 and the micrometer-level annular groove 22 located on both sides, can, on the one hand, block the high-pressure area generated by the spiral groove and balance the pressure gradient on the inner diameter side to reduce leakage, and on the other hand, increase the average film thickness of the liquid film and reduce the generation of heat dissipation due to fluid viscosity.

[0059] Continue reading Figure 2 And see also Figure 3 In some embodiments of this utility model, the submillimeter-level spiral groove 231 and the micrometer-level spiral groove 232 both extend radially spirally to the outer wall of the moving ring 20 or the stationary ring 10, and the micrometer-level spiral groove 232 forms a three-sided surrounding structure of the submillimeter-level spiral groove 231 in the circumferential direction.

[0060] The load-bearing capacity of the sealing end face mainly depends on the dynamic pressure effect of the fluid film 30 on the end face. In traditional single spiral groove designs, the dynamic pressure effect is dominated by a single-size groove, resulting in limited load-bearing capacity and sensitivity to fluctuations in operating conditions (such as changes in rotational speed and medium viscosity).

[0061] This embodiment of the invention achieves synergistic enhancement of the dynamic pressure effect through a radially graded layout of dual-scale spiral grooves. The radially graded layout of both ensures that the dynamic pressure effect covers the entire flow from the high-pressure zone to the low-pressure zone. When the high-speed fluid enters from the sub-millimeter-scale spiral groove 231, it first obtains initial dynamic pressure support through the groove structure with a larger depth; then, when it enters the micrometer-scale spiral groove 232, the geometric abrupt change of the groove with a smaller depth further enhances the dynamic pressure effect and strengthens the anti-interference capability.

[0062] Furthermore, this embodiment of the invention achieves the superposition and complementarity of dual-scale dynamic pressure effects through a composite groove design: the submillimeter-level spiral groove 231 (main channel) serves as a radially extending main fluid channel, and its larger groove depth allows more fluid to flow along the spiral direction, forming basic dynamic pressure support. When the fluid flows in the spiral groove, the high-pressure fluid generated by the groove wall obstruction gradually accumulates radially, providing initial opening force for the sealing end face.

[0063] The micron-sized spiral groove 232 (secondary channel) forms a constraint boundary on three sides of the submillimeter-sized spiral groove 231 by surrounding the submillimeter-sized spiral groove 231 on three circumferential sides (i.e., the micron-sized spiral groove 232 surrounds the circumferential sides and one end of the submillimeter-sized spiral groove 231). After the fluid enters the micron-sized spiral groove 232, it is further compressed by the groove wall of the micron-sized spiral groove 232, and the fluid velocity is restricted in the circumferential direction, which leads to a further increase in the fluid pressure gradient within the micron-sized spiral groove 232. At the same time, an additional local high-pressure zone is generated at the root of the micron-sized spiral groove 232 (adjacent to the submillimeter-sized spiral groove 231) due to geometric abrupt change, forming a secondary dynamic pressure support.

[0064] Furthermore, the micron-level spiral groove 232 surrounds the submillimeter-level spiral groove 231 on three sides in the circumference. The structure of the micron-level spiral groove 232 surrounding the submillimeter-level spiral groove 231 is equivalent to forming a "constraint wall" in the circumference of the submillimeter-level spiral groove 231, which restricts the disorderly diffusion of fluid to non-target areas (such as the outer diameter side or inner diameter side of the sealing end face).

[0065] Figure 4 This is a cross-sectional view of the non-contact end-face sealing assembly provided in this embodiment of the utility model.

[0066] See Figure 4 In some embodiments of this utility model, the depth of the micron-level spiral groove 232 is H1, wherein the value of H1 ranges from 3μm to 30μm, for example, H1 can be 3μm, 6μm, 10μm, 20μm, or 30μm. The depth of the submillimeter-level spiral groove 231 is H2, wherein the value of H2 ranges from 100μm to 1000μm, for example, H2 can be 100μm, 300μm, 500μm, 800μm, or 1000μm.

[0067] Continue reading Figure 4 In some embodiments of this invention, the depth of the micron-level annular groove 22 is H3, where H3 ranges from 3μm to 30μm, for example, H3 can be 3μm, 6μm, 10μm, 20μm, or 30μm. The depth of the submillimeter-level annular groove 21 is H4, where H4 ranges from 100μm to 1000μm, for example, H4 can be 100μm, 300μm, 500μm, 800μm, or 1000μm.

[0068] This is equivalent to the depth H1 of the micrometer-scale spiral groove 232 being equal to the depth H3 of the micrometer-scale annular groove 22. The depth H2 of the submillimeter-scale spiral groove 231 is equal to the depth H4 of the submillimeter-scale annular groove 21.

[0069] Continue reading Figure 2 In some embodiments of this utility model, the helix angle of the micron-level helical groove 232 is α, wherein the value of α ranges from 12° to 24°, for example, α can be 12°, 18°, and 24°, etc. The helix angle of the submillimeter-level helical groove 231 is equal to the helix angle of the micron-level helical groove 232.

[0070] In some embodiments of this utility model, the width of the micron-level spiral groove 232 ranges from 3mm to 30mm; for example, the width of the micron-level spiral groove 232 can be 3mm, 8mm, 10mm, 20mm, and 30mm, etc.

[0071] In some embodiments of this utility model, the radial length of the micron-level spiral groove 232 is 30% to 80% of the diameter of the sealing end face; in other words, the ratio of the radial length of the micron-level spiral groove 232 to the diameter of the sealing end face is 0.3 to 0.8.

[0072] In some embodiments of this utility model, the number of micron-level spiral grooves 232 on the sealing end face is 6 to 24, that is, the number of micron-level spiral grooves 232 can be set to 6, 10, 20 or 24 depending on the size of the sealing component and the usage requirements. Among them, the number of submillimeter-level spiral grooves 231 is equal to the number of micron-level spiral grooves 232.

[0073] In some embodiments of this utility model, the width of the submillimeter-level spiral groove 231 ranges from 1mm to 10mm; for example, the width of the submillimeter-level spiral groove 231 can be 1mm, 3mm, 5mm, 8mm, or 10mm.

[0074] In some embodiments of this utility model, the radial length of the submillimeter-level spiral groove 231 is 20% to 70% of the diameter of the sealing end face. In other words, the ratio of the radial length of the submillimeter-level spiral groove 231 to the diameter of the sealing end face is 0.2 to 0.7.

[0075] In some embodiments of this utility model, the distance between the micron-sized annular groove 22 and the inner wall of the moving ring 20 or the stationary ring 10 ranges from 1 mm to 4 mm; the width of the micron-sized annular groove 22 ranges from 2 mm to 5 mm.

[0076] The distance between the submillimeter-level annular groove 21 and the inner wall of the moving ring 20 or the stationary ring 10 ranges from 2mm to 3mm; the width of the submillimeter-level annular groove 21 ranges from 1mm to 4mm.

[0077] The working principle of the non-contact end-face sealing assembly provided in this embodiment of the invention is explained as follows:

[0078] Under the combined effect of the circumferential shear force generated by the high-speed rotation of the rotating ring 20 and the pressure difference between the inner and outer diameters of the sealing ring, the high-pressure fluid inside the sealing cavity is directionally drawn into the gap at the sealing end face. The sub-millimeter and micrometer-level composite grooves (sub-millimeter-level spiral groove 231 as the main groove and micrometer-level spiral groove 232 as the support groove) opened on the end face of the rotating ring 20 increase the fluid film thickness and reduce the fluid shear rate through graded flow guidance and geometric constraints, thereby effectively suppressing viscous heat dissipation. Compared with the traditional micrometer-level shallow groove structure, the reduced fluid shearing effect reduces the viscous heat dissipation.

[0079] Meanwhile, the low-temperature fluid (usually at room temperature or slightly above ambient temperature) inside the sealed cavity is fully mixed with the high-temperature fluid at the end face through the sub-millimeter spiral groove 231, which enhances the heat exchange efficiency at the end face and achieves a significant reduction in the temperature of the fluid film 30, fundamentally solving the risk of liquid film vaporization and end face thermal deformation caused by high temperature.

[0080] Regarding the enhancement of the hydrodynamic effect, the root of the micron-sized spiral groove 232 experiences a dramatic hydrodynamic effect due to a geometrical abrupt change (sudden reduction in groove depth) (increasing the pressure difference between the high-pressure zone at the groove root and the low-pressure zone at the groove top). This, combined with the shallow groove hydrodynamic performance retained by the sub-millimeter-sized spiral groove 231 (where the low-pressure zone at the groove top guides fluid injection and the high-pressure zone at the groove root provides support), creates a dual-scale hydrodynamic superposition effect. This effect further improves the sealing load-bearing capacity, increases the total opening force compared to the single micron-sized spiral groove 232 structure, and significantly enhances the stability of the friction pair.

[0081] For leakage control, the fluid film thickness on the downstream side undergoes a step change (from a large film thickness in the trench area to a stable film thickness in the dam area). The annular groove, by blocking the local high-pressure zone formed by the upstream spiral groove, utilizes the enhanced hydrostatic pressure effect within the sub-millimeter annular groove 21 to reduce the pressure gradient on the inner diameter side, thus stably controlling the leakage rate and balancing the reliability and safety of the seal. This embodiment of the invention achieves the optimized operational goals of low heat generation, high load capacity, and low leakage in high-speed sealing scenarios.

[0082] This utility model also provides a high-speed pump, which includes a housing and a non-contact end face sealing assembly as described above, wherein the non-contact end face sealing assembly is disposed inside the housing.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A non-contact end-face sealing assembly, characterized in that, include: Static ring; A rotating ring is spaced apart from and opposite to the stationary ring, and its end face opposite to the stationary ring forms a sealing end face. The downstream region of the sealing end face near the center of the stationary ring or the rotating ring is a low-pressure region. The low-pressure region has interconnected sub-millimeter-level annular grooves and micrometer-level annular grooves. The two sides of the micrometer-level annular grooves form a sealing dam area. The upstream region of the sealing end face away from the center of the stationary ring or the rotating ring is a high-pressure region. The high-pressure region has multiple spiral groove groups arranged periodically along the circumference. Each spiral groove group includes interconnected sub-millimeter-level spiral grooves and micrometer-level spiral grooves. The non-groove area between two adjacent spiral groove groups forms a sealing weir area.

2. The non-contact end-face sealing assembly according to claim 1, characterized in that, The micron-level annular grooves are located on both sides of the submillimeter-level annular grooves; The submillimeter-level annular groove and the micrometer-level annular groove located on both sides of the submillimeter-level annular groove are respectively opened on three virtual circles with different radii centered on the same center, and the center of the circle is located on the axial center line of the sealing end face.

3. The non-contact end-face sealing assembly according to claim 1, characterized in that, Both the submillimeter-level spiral groove and the micrometer-level spiral groove extend radially spirally to the outer wall of the moving ring or the stationary ring, and the micrometer-level spiral groove forms a three-sided surrounding structure of the submillimeter-level spiral groove in the circumferential direction.

4. The non-contact end-face sealing assembly according to any one of claims 1 to 3, characterized in that, The depth of the micron-level spiral groove is H1, where the value of H1 ranges from 3μm to 30μm; the depth of the submillimeter-level spiral groove is H2, where the value of H2 ranges from 100μm to 1000μm.

5. The non-contact end-face sealing assembly according to any one of claims 1 to 3, characterized in that, The depth of the micron-level annular groove is H3, where H3 ranges from 3μm to 30μm; the depth of the submillimeter-level annular groove is H4, where H4 ranges from 100μm to 1000μm.

6. The non-contact end-face sealing assembly according to any one of claims 1 to 3, characterized in that, The helix angle of the micron-level spiral groove is α, where the value of α ranges from 12° to 24°. The width range of the micron-level spiral groove is 3mm to 30mm; The radial length of the micron-sized spiral groove is 30% to 80% of the diameter of the sealing end face; The number of micron-level spiral grooves on the sealing end face is 6 to 24.

7. The non-contact end-face sealing assembly according to claim 6, characterized in that, The helix angle of the submillimeter-level spiral groove is equal to that of the micrometer-level spiral groove, and the number of the submillimeter-level spiral groove is equal to the number of the micrometer-level spiral groove; The width range of the sub-millimeter spiral groove is 1mm to 10mm; The radial length of the sub-millimeter-level spiral groove is 20% to 70% of the diameter of the sealing end face.

8. The non-contact end-face sealing assembly according to any one of claims 1 to 3, characterized in that, The distance between the micron-sized annular groove and the inner wall of the moving ring or the stationary ring ranges from 1 mm to 4 mm; the width of the micron-sized annular groove ranges from 2 mm to 5 mm.

9. The non-contact end-face sealing assembly according to any one of claims 1 to 3, characterized in that, The distance between the submillimeter-level annular groove and the inner wall of the moving ring or the stationary ring ranges from 2mm to 3mm; the width of the submillimeter-level annular groove ranges from 1mm to 4mm.

10. A high-speed pump, characterized in that, It includes a housing and a non-contact end-face sealing assembly as described in any one of claims 1 to 9, wherein the non-contact end-face sealing assembly is disposed within the housing.

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