A dry gas seal device with large shaft diameter and multi-layer structure coupling

Abstract

This invention belongs to the field of fluid machinery shaft end sealing technology, and discloses a large-diameter, multi-layered coupled dry gas sealing device, including a rotating ring, a stationary ring, a rotating shaft, and a front-end comb-tooth seal. A rotating ring seat is fitted onto the outer wall of the rotating shaft. The rotating ring and stationary ring are fitted onto the rotating ring seat, with the stationary ring seat installed behind the stationary ring. The rotating ring seat is located on the rotating shaft, and a front-end comb-tooth seal is located radially outward of the rotating ring seat. A dry gas sealing seat is located radially outward of the front-end comb-tooth seal. The rotating ring has multiple stages of rotating ring sealing end faces, and the stationary ring has multiple stages of stationary ring sealing end faces. A sealing gas film is formed between the sealing end faces of the rotating and stationary rings. This invention uses the rotation of the rotating shaft to drive the rotating ring to rotate. The sealing medium flowing from the front-end comb-tooth seal sequentially flows into the multi-stage dynamic pressure grooves of the rotating ring, forming a multi-stage high-pressure region that forces open the stationary ring to form a sealing gas film, achieving a sealing effect on the working medium on the medium side. This effectively reduces the deformation of the rotating ring end face, enhances the stiffness of the sealing gas film, reduces the volume of the dry gas sealing device for large shaft diameters, enables rapid start-up and shutdown of the dry gas seal, reduces operating and maintenance costs, and improves operational stability.

Description

Technical Field

[0001] This invention belongs to the field of fluid machinery shaft end sealing technology, specifically relating to a large-diameter multi-layer structure coupled dry gas sealing device. Background Technology

[0002] In the field of fluid machinery engineering, modern rotating machinery continues to evolve towards larger shaft diameters, higher power, and extreme operating parameters, leading to unprecedented technical challenges for shaft end sealing systems. Traditional sealing methods, such as labyrinth seals, packing seals, and other contact mechanical seals, are limited by inherent defects. They rely on solid friction contact, are sensitive to operating conditions, and suffer from excessively high seal outer diameter linear velocity at high speeds, making it difficult to meet the demands of high-parameter operating conditions. Especially in high-temperature, high-pressure, and frequent start-stop scenarios, traditional seals generally suffer from bottlenecks such as uncontrolled leakage, increased friction, severe thermal deformation, and soaring maintenance costs, seriously restricting equipment reliability, long-term operating capability, and system stability.

[0003] Dry gas seals, as a type of non-contact hydrodynamic lubrication seal, achieve zero-friction operation through a micron-level sealing gas film formed on the sealing end face. Theoretically, they possess advantages such as extremely low leakage, no frictional loss, low system power consumption, and long service life, making them the mainstream solution for shaft end sealing in high-end rotating machinery. However, engineering practice shows that conventional dry gas seals have significant limitations under transient start-stop conditions. At low speeds, the weakening of the hydrodynamic effect leads to delayed gas film establishment, posing a risk of instantaneous contact at the sealing end face. Secondly, frictional heat accumulation and delayed heat dissipation may induce localized high-temperature areas, accelerating thermoelastic deformation of the sealing ring and even thermal cracking failure. Thirdly, insufficient sealing film stiffness during transient pressure fluctuations may cause leakage to exceed design values, impacting the environment. Existing technologies mostly alleviate these problems through groove optimization or material upgrades, but for large-diameter dry gas seals, a novel dry gas sealing device is needed to ensure sealing strength under frequent start-stop conditions. Summary of the Invention

[0004] To address the shortcomings of existing gas sealing devices in ensuring sealing strength under frequent start-stop conditions, the present invention aims to provide a dry gas sealing device with a large-diameter, multi-layered structure coupling. This device can effectively reduce the deformation of the dynamic ring end face, enhance the rigidity of the sealing gas film, reduce the volume of the dry gas sealing device for large-diameter shafts, achieve rapid start-stop of the dry gas seal, ensure sealing strength under frequent load changes, reduce operation and maintenance costs, and improve operational stability.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] A large-diameter, multi-layered, coupled dry gas sealing device includes a rotating ring, a stationary ring, a rotating ring seat, a stationary ring seat, a rotating shaft, a front-end comb seal, and a dry gas sealing seat.

[0007] The rotating ring seat is fitted onto the outer wall of the rotating shaft. The rotating ring and the stationary ring are installed on the rotating ring seat in a relatively mating manner. The stationary ring seat is installed behind the stationary ring. The rotating ring seat is set on the rotating shaft. A front comb-tooth seal is set on the outer side of the rotating ring seat in the radial direction. A dry gas seal seat is set on the outer side of the front comb-tooth seal in the radial direction. The rotating ring, stationary ring, rotating ring seat, stationary ring seat and the center of the rotating shaft are located on the same straight line. The rotating ring is provided with a multi-stage rotating ring sealing end face. The stationary ring is provided with a multi-stage stationary ring sealing end face. A sealing gas film is formed between the sealing end faces of the rotating ring and the stationary ring.

[0008] Furthermore, the number of stages n of the rotating ring sealing end face is 1 to 10, with the rotating ring sealing end face closest to the rotating shaft being the first stage. In the radial direction, the number of stages increases sequentially as the radius increases.

[0009] Furthermore, the stationary ring sealing end face and the dynamic ring sealing end face are mated together in the axial direction.

[0010] Furthermore, it also includes a stationary ring pusher ring, with the stationary ring seat mounted behind the stationary ring via a spring and the stationary ring pusher ring fitting against the back of the stationary ring.

[0011] Furthermore, it also includes a bushing clamping component, which is arranged opposite to the rotating ring seat on the rotating shaft.

[0012] Furthermore, the sealing end face of the dynamic ring has an included angle α in the radial direction. q Angle α q The maximum value is 0° to 45°, q = 1, 2, 3..., n, where q represents the sealing end face level.

[0013] Furthermore, a dynamic pressure groove is provided on the sealing end face of the dynamic ring.

[0014] Furthermore, the dynamic pressure grooves are evenly arranged in the circumferential direction, with several dynamic pressure grooves on each sealing end face. The groove shape is T-shaped groove, spiral groove, or tree-shaped groove, and the groove depth is h. gq The range is 1 to 50 μm, and q = 1, 2, 3..., n, where q represents the sealing end face level.

[0015] Furthermore, the stationary ring sealing end face has an included angle β in the radial direction. q The included angle β of the stationary ring sealing end face q The angle α between the sealing end face of the rotating ring and the radial direction exists. q equal.

[0016] Furthermore, the outer diameter r of each sealing end face dmq Calculated using the following formula:

[0017] r dmq =r ri +(r ro -rri ) / n*q

[0018] Where, r ri r is the inner diameter of the moving ring. ro Let q be the outer diameter of the moving ring, q = 1, 2, 3..., n, where q represents the number of sealing end face stages, and the outer diameter r of the last stage sealing end face is... dmn The outer diameter is equal to the outer diameter r of the moving ring. ro ;

[0019] The thickness of the sealing gas film is h. q q = 1, 2, 3..., n, where q represents the number of sealing end face stages, h q The range is 1–100 μm.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] This invention discloses a large-diameter, multi-layered, coupled dry gas sealing device. By employing a multi-stage sealing end-face structure, this invention effectively suppresses heat load concentration and deformation at the end face. Compared to traditional single-end-face dry gas seals, the pressure gradient distribution mechanism within the sealing end face is more rational, effectively reducing axial deformation. This invention features a multi-stage sealing end face on the rotating ring and a corresponding sealing end face on the stationary ring. Rotation of the shaft drives the rotating ring, and the sealing medium flowing from the front comb-tooth seal sequentially flows into the multi-stage dynamic pressure grooves of the rotating ring, forming a multi-stage high-pressure region that forces open the stationary ring to form a sealing gas film. This achieves a sealing effect on the working medium on the medium side, effectively reducing the deformation of the rotating ring end face, enhancing the rigidity of the sealing gas film, reducing the volume of the dry gas sealing device for large-diameter shafts, enabling rapid start-up and shutdown of the dry gas seal, ensuring sealing strength under frequent load changes, reducing operating and maintenance costs, and improving operational stability. The sealing device in this invention can quickly establish a high-rigidity gas film to eliminate start-stop contact, significantly accelerating the establishment process of the high-rigidity sealing gas film. In the dry gas seal start-up stage, the rotating shaft drives the rotating ring, which in turn drives the multi-stage dynamic pressure groove to synchronously induce the fluid dynamic pressure effect, so that each sealing end face generates a stable gas film with high load-bearing rigidity in a short time, completely eliminating the risk of sealing end face contact caused by insufficient dynamic pressure in the low speed stage, and achieving zero-wear start-stop.

[0022] Furthermore, when the sealing medium flows through the progressively depressurized dynamic pressure groove, the kinetic energy is converted into controllable pressure energy rather than frictional heat energy. Combined with the geometric structure of the dynamic pressure groove, it guides the flow of the sealing medium and optimizes the temperature field distribution on the sealing end face.

[0023] Furthermore, in this invention, multi-stage dynamic pressure grooves are provided within the multi-stage sealing end face, which can maintain precise leakage control under variable load conditions. When the system encounters pressure fluctuations or sudden speed changes, the adaptive pressure feedback generated by each stage of dynamic pressure grooves can better balance the disturbance and control the leakage within a certain range. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of a dry gas sealing device with a large shaft diameter and multi-layer structure coupling according to Embodiment 1 of the present invention;

[0026] Figure 2 This is a cross-sectional view of a dry gas sealing device with a large shaft diameter and multi-layer structure coupling according to Embodiment 1 of the present invention;

[0027] Figure 3 This is a schematic diagram of the dynamic and static ring structures of Embodiment 1 of the present invention;

[0028] Figure 4 This is a schematic diagram of the dynamic ring sealing end face of Embodiment 1 of the present invention;

[0029] Figure 5 This is a schematic diagram of the dynamic ring sealing end face of Embodiment 2 of the present invention;

[0030] Figure 6 The dynamic and static ring edges of Embodiment 2 of the present invention Figure 5 Cross-sectional view of line AA.

[0031] In the diagram, 1. Moving ring; 2. Stationary ring; 3. Moving ring seat; 4. Stationary ring push ring; 5. Stationary ring seat; 6. Rotating shaft; 7. Shaft sleeve clamping part; 8. Spring; 9. Front comb tooth seal; 10. Dry gas seal seat; 11. Dynamic pressure groove. Detailed Implementation

[0032] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0033] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0034] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0035] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0036] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0037] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0038] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0039] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0040] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0041] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0042] The large shaft diameter of this invention refers to a dry gas seal with an inner diameter of 400 mm or more.

[0043] See Figure 1 The present invention provides a large-diameter multi-layer structure coupled dry gas sealing device, comprising a dynamic ring 1, a stationary ring 2, a dynamic ring seat 3, a stationary ring push ring 4, a stationary ring seat 5, a rotating shaft 6, a shaft sleeve clamping component 7, a spring 8, a front-end comb seal 9, and a dry gas sealing seat 10.

[0044] Among them, the moving ring seat 3 is sleeved on the outer wall of the rotating shaft 6, the moving ring 1 and the stationary ring 2 are installed on the moving ring seat 3 in a relatively cooperative manner, the stationary ring seat 5 is installed behind the stationary ring 2 by means of the spring 8 and the stationary ring push ring 4, and the stationary ring push ring 4 and the back of the stationary ring 2 are tightly fitted together by the action of the spring 8. The bushing clamping part 7 is arranged opposite to the moving ring seat 3 on the rotating shaft. A front comb tooth seal 9 is provided on the radial outer side of the moving ring seat 3, and a dry gas seal seat 10 is provided on the radial outer side of the front comb tooth seal 9. The moving ring 1, stationary ring 2, moving ring seat 3, stationary ring push ring 4, stationary ring seat 5 and the center of the rotating shaft 6 are located on the same straight line.

[0045] The rotating ring 1 is provided with multiple stages of rotating ring sealing end faces. The number of stages n of the rotating ring sealing end faces is 1 to 10. The one closest to the rotating shaft 6 is the first stage. In the radial direction, the number of stages increases sequentially as the radius increases.

[0046] Similarly, the stationary ring 2 is provided with multiple stationary ring sealing end faces. The stationary ring sealing end faces and the dynamic ring sealing end faces cooperate with each other in the axial direction, and a sealing gas film is formed between the dynamic and stationary ring sealing end faces.

[0047] See Figure 6 The sealing end face of the dynamic ring has an included angle α in the radial direction. q Angles α at all levels q The maximum value is α, where α ranges from 0° to 45°, and q = 1, 2, 3, ..., n, where q represents the number of sealing end face levels.

[0048] The dynamic ring sealing end face is provided with dynamic pressure grooves 11, which are evenly arranged in the circumferential direction, and the number of dynamic pressure grooves 11 on each sealing end face is n. g The dynamic pressure groove 11 has a groove shape such as a T-shaped groove, a spiral groove, or a tree-shaped groove, and a groove depth h. gq The range is 1 to 50 μm, and q = 1, 2, 3..., n, where q represents the sealing end face level.

[0049] The static ring sealing end face has an included angle β in the radial direction. q The included angle β of the sealing end faces of each level of stationary ring q Angle α with the sealing end face of the rotating ring q equal.

[0050] See Figure 4 and Figure 5 The inner diameter of the moving ring is r ri The outer diameter of the moving ring is r ro The inner diameter of the stationary ring is r si The outer diameter of the stationary ring is r so The outer diameter of each sealing end face is r dmq q = 1, 2, 3..., n, where q represents the sealing end face level, calculated as r dmq =r ri +(r ro -r ri ) / n*q, the root radius of each level of dynamic pressure groove 11 is r gq q = 1, 2, 3, ..., n, where q represents the number of sealing end face stages, and the outer diameter r of the last stage sealing end face is... dmn The outer diameter is equal to the outer diameter r of the moving ring. ro .

[0051] A sealing gas film exists between the rotating ring 1 and the stationary ring 12, and the thickness of each gas film is h. q q = 1, 2, 3..., n, where q represents the number of sealing end face stages, h q The range is 1–100 μm.

[0052] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0053] Example 1

[0054] like Figures 1-4 As shown, this embodiment provides a dry gas sealing device with a large shaft diameter and multi-layer structure coupling, including a rotating ring 1, a stationary ring 2, a rotating ring seat 3, a stationary ring push ring 4, a stationary ring seat 5, a rotating shaft 6, a shaft sleeve clamping component 7, a spring 8, a front end comb seal 9, and a dry gas sealing seat 10.

[0055] The moving ring seat 3 is sleeved on the outer wall of the rotating shaft 6. The moving ring 1 and the stationary ring 2 are installed on the moving ring seat 3 in a relatively cooperative manner. The stationary ring seat 5 is installed behind the stationary ring 2 by means of the spring 8 and the stationary ring push ring 4. The stationary ring push ring 4 and the back of the stationary ring 2 are tightly fitted together by the action of the spring 8. The bushing clamping member 7 is arranged opposite to the moving ring seat 3 on the rotating shaft. A front comb seal 9 is provided on the radial outer side of the moving ring seat 3. A dry gas seal seat 10 is provided on the radial outer side of the front comb seal. The moving ring 1, stationary ring 2, moving ring seat 3, stationary ring push ring 4, stationary ring seat 5 and the center of the rotating shaft 6 are located on the same central axis.

[0056] In this embodiment 1, a single-stage dynamic ring sealing end face is provided on the dynamic ring 1, and the number of stages n of the sealing end face is 1. Similarly, a single-stage static ring sealing end face is also provided on the stationary ring. The stationary ring sealing end face and the dynamic ring sealing end face cooperate with each other in the axial direction, and a sealing gas film is formed between the dynamic and stationary ring sealing end faces.

[0057] In this embodiment 1, the dynamic ring sealing end face has an included angle α1 in the radial direction, α1 = 15°, and similarly, the static ring sealing end face has an included angle β1 in the radial direction, β1 = 15°, which is equal to α1.

[0058] In this embodiment 1, dynamic pressure grooves are provided on the sealing end face of the dynamic ring. The dynamic pressure grooves are evenly arranged in the circumferential direction, and the number of dynamic pressure grooves on each sealing end face is n. g =6, the dynamic pressure groove is a T-shaped groove, and the depth of the dynamic pressure groove is h. g1 =20μm. To facilitate observation, the diameter is enlarged by 1000 times in the axial direction when drawing.

[0059] In this embodiment 1, the inner diameter of the moving ring is r. ri =100mm, outer diameter is r ro =120mm, inner diameter of stationary ring is r si =100mm, outer diameter is r so =120mm. Since this embodiment is a single-stage sealing end face, the root radius of the first-stage dynamic pressure groove is 106.6mm.

[0060] In this embodiment 1, a sealing gas film exists between the moving ring 1 and the stationary ring 12. The thickness of the primary gas film is h1 = 50 μm. For ease of observation, the thickness is magnified 1000 times in the axial direction when drawing. Figure 3 As shown.

[0061] Example 2

[0062] like Figures 5-6 As shown in the figure, this embodiment provides a dry gas sealing device with a large shaft diameter and multi-layer structure coupling. Compared with embodiment 1, in this embodiment 2, the moving ring 1 is provided with 3 levels of moving ring sealing end faces. The first level is near the rotating shaft. In the radial direction, the number of levels increases with the increase of the radius. Similarly, 3 levels of stationary ring sealing end faces are provided on the stationary ring. The stationary ring sealing end faces and the moving ring sealing end faces cooperate with each other in the axial direction, and a sealing gas film is formed between the sealing end faces of the moving ring 1 and the stationary ring 12.

[0063] In this embodiment 2, the sealing end face of the dynamic ring has included angles α1 = 5°, α2 = 10°, and α3 = 15° in the radial direction, and similarly, the sealing end face of the stationary ring has included angle β in the radial direction. q , β1, β2, β3 are equal to α1, α2, α3 respectively, q=1, 2, 3..., n.

[0064] In this embodiment 2, dynamic pressure grooves are provided on the sealing end face of the dynamic ring. The dynamic pressure grooves are evenly arranged in the circumferential direction, and the number of dynamic pressure grooves on each sealing end face is n. g =12, the dynamic pressure groove is a T-shaped groove, and the depth of the dynamic pressure groove is h. g1 =15μm, h g2 =15μm, h g3 =15μm. To facilitate observation, the diameter is magnified 1000 times in the axial direction when plotting.

[0065] In this embodiment 2, the inner diameter of the moving ring is r. ri =180mm, outer diameter is r ro =360mm, inner diameter of stationary ring is r si =180mm, outer diameter is r so =360mm, the outer diameter of each sealing end face is r dm1 =240mm, r dm2 =300mm, the root radius r of each level of dynamic pressure groove g1 =210mm, r g2 =270mm, r g3 =330mm. A sealing gas film exists between the dynamic and static rings, with thicknesses of h1 = 50μm, h2 = 50μm, and h3 = 50μm at each stage. For ease of observation, the thickness is magnified 1000 times in the axial direction when drawing. Figure 6 As shown.

[0066] The working process of the aforementioned large-diameter, multi-layered coupled dry gas sealing device is as follows: A dynamic pressure groove 11 is provided on the rotating ring 1. When the dry gas seal starts to operate, the sealing medium mixes with the high-temperature medium flowing through the front comb seal 9 for initial cooling, and then flows into the rotating ring 1 and the stationary ring 2. When the space between the rotating ring 1 and the stationary ring 2 is filled with the sealing medium, the sealing medium first fills the dynamic pressure groove 11, starting from the first-stage sealing end face, and sequentially fills the dynamic pressure grooves of the lower-stage sealing end faces. When the pressure is sufficient, it pushes open the stationary ring 2, forming a stable sealing gas film, ensuring the stable operation of the dry gas seal. When operating conditions such as rotational speed need to change, the multi-stage sealing end face structure can effectively ensure the constant stiffness of the dry gas seal during variable load processes. At the same time, by setting a multi-stage sealing end face structure, the degree of thermoelastic deformation of the conventional dry gas seal sealing end face can be reduced, effectively suppressing the concentration and deformation of end face heat load, and reducing the risk of instability and reduced reliability of the sealing equipment.

[0067] This invention features a multi-stage sealing end face on the rotating ring. Several dynamic pressure grooves are engraved along the circumference of the rotating ring's sealing end face. A corresponding sealing end face is provided on the stationary ring. Rotation of the shaft drives the rotating ring to rotate, and the sealing medium flowing from the front comb-tooth seal sequentially flows into the multi-stage dynamic pressure grooves of the rotating ring, forming a multi-stage high-pressure zone that forces open the stationary ring to form a sealing gas film. This achieves the sealing effect on the working medium side, effectively reducing the deformation of the rotating ring end face, enhancing the rigidity of the sealing gas film, reducing the volume of the dry gas sealing device when the shaft diameter is large, enabling rapid start-up and shutdown of the dry gas seal, ensuring sealing strength under frequent load changes, reducing operating and maintenance costs, and improving operational stability.

[0068] The above description is only of the preferred embodiment of the present invention and should not be construed as limiting the scope of the claims. The present invention is not limited to the above embodiments, and variations in its specific structure are permitted. All variations made within the scope of the independent claims of the present invention are also within the scope of protection of the present invention.

[0069] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

Claims

1. A large-diameter, multi-layer structure coupled dry gas sealing device, characterized in that, It includes a rotating ring (1), a stationary ring (2), a rotating ring seat (3), a stationary ring seat (5), a rotating shaft (6), a front comb seal (9), and a dry gas seal seat (10); Among them, the moving ring seat (3) is sleeved on the outer wall of the rotating shaft (6), the moving ring (1) and the stationary ring (2) are installed on the moving ring seat (3) in relative cooperation, the stationary ring seat (5) is installed behind the stationary ring (2), the moving ring seat (3) is set on the rotating shaft (6), the front comb seal (9) is set on the outer side of the moving ring seat (3) in the radial direction, and the dry gas seal seat (10) is set on the outer side of the front comb seal (9) in the radial direction. The moving ring (1), the stationary ring (2), the moving ring seat (3), the stationary ring seat (5) and the center of the rotating shaft (6) are located on the same straight line. The moving ring (1) is provided with a multi-stage moving ring sealing end face, and the stationary ring (2) is provided with a multi-stage stationary ring sealing end face. A sealing gas film is formed between the sealing end faces of the moving ring (1) and the stationary ring (2). Among them, the sealing end face of the dynamic ring has an included angle in the radial direction. α q included angle α q The maximum value is 0°~45°, q=1, 2, 3, ..., n, where q represents the sealing end face level; the stationary ring sealing end face has an included angle in the radial direction. β q included angle of the stationary ring sealing end face β q The angle between the sealing end face of the rotating ring and the radial direction α q equal.

2. The large-diameter multi-layer structure coupled dry gas sealing device according to claim 1, characterized in that, The number of stages n of the dynamic ring sealing end face is 1 to 10. The dynamic ring sealing end face near the rotating shaft (6) is the first stage. In the radial direction, the number of stages increases sequentially as the radius increases.

3. The large-diameter multi-layer structure coupled dry gas sealing device according to claim 1, characterized in that, The stationary ring sealing face and the rotating ring sealing face mate with each other in the axial direction.

4. The large-diameter multi-layer structure coupled dry gas sealing device according to claim 1, characterized in that, It also includes a stationary ring pusher (4), and the stationary ring seat (5) is installed behind the stationary ring (2) by means of a spring (8) and the stationary ring pusher (4), with the stationary ring pusher (4) fitting against the back of the stationary ring (2).

5. The large-diameter multi-layer structure coupled dry gas sealing device according to claim 1, characterized in that, It also includes a bushing clamping component (7), which is arranged opposite to the rotating ring seat (3) on the rotating shaft (6).

6. The large-diameter multi-layer structure coupled dry gas sealing device according to claim 1, characterized in that, A dynamic pressure groove (11) is provided on the sealing end face of the dynamic ring.

7. The large-diameter multi-layer structure coupled dry gas sealing device according to claim 6, characterized in that, The dynamic pressure grooves (11) are evenly arranged in the circumferential direction. There are several dynamic pressure grooves (11) on each sealing end face. The groove shape of the dynamic pressure grooves (11) is T-shaped groove, spiral groove or tree-shaped groove. The groove depth of the dynamic pressure grooves (11) is h. gq The range is 1~50μm, q=1, 2, 3, ..., n, where q represents the sealing end face level.

8. The large-diameter multi-layer structure coupled dry gas sealing device according to claim 6, characterized in that, outer diameter r of each sealing end face dmq Calculated using the following formula: r dmq =r ri +(r ro -r ri ) / n q Where, r ri r is the inner diameter of the moving ring. ro Let q be the outer diameter of the moving ring, q = 1, 2, 3, ..., n, where q represents the number of sealing end face stages, and the outer diameter r of the last stage sealing end face is... dmn The outer diameter is equal to the outer diameter r of the moving ring. ro ; The thickness of the sealing gas film is h. q q = 1, 2, 3, ..., n, where q represents the number of sealing end face stages, h q The range is 1~100μm.

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