Mechanical seal device

Abstract

The application discloses a mechanical sealing device. The inner side groove extends in the reverse direction of the rotation direction of the sealing end face from the inner edge of the sealing end face; the outer side groove comprises an outer side first groove, an outer side second groove and an outer side third groove arranged in a herringbone shape; the outer side second groove is arranged in one-to-one correspondence with the inner side groove in the radial direction of the sealing end face, the outer side second groove has a first end and a second end, the width of the outer side second groove gradually decreases from the first end to the second end, and the outer side first groove and the outer side third groove are both located at the first end and arranged in a V shape; one end of the outer side first groove and one end of the outer side third groove are connected to the first end in close proximity to each other, and the other end of the outer side third groove extends to between the outer side second groove of a circumferentially adjacent outer side groove and the inner side groove. The application can reduce the friction and wear of the sealing end face in the full speed range and can reduce the leakage without changing the balanced film thickness.

Description

Technical Field

[0001] This invention relates to the field of fluid sealing technology, and in particular to a mechanical sealing device. Background Technology

[0002] Nuclear energy, as a clean and efficient energy source, occupies an important position in the global energy structure. The main coolant pump (referred to as the "main pump") is the only large rotating device in the primary loop of a nuclear power plant, and is often referred to as the "heart" of the primary loop. The main pump shaft seal is a key component at the pressure boundary of the primary loop of a nuclear power plant. It not only faces complex operating conditions such as high-temperature and high-pressure media, large-scale friction, and multiphase flow, but also requires stable and controllable leakage over a long period of continuous operation.

[0003] The groove shape is crucial in the design of mechanical seals, determining the hydrodynamic behavior between the sealing faces and directly affecting sealing performance. A well-designed groove promotes the formation of a stable lubricating film on the sealing faces, effectively reducing direct contact friction, lowering wear, and extending seal life. Furthermore, the groove shape influences the leakage rate; a good design ensures extremely low leakage under various operating conditions, meeting the stringent sealing performance requirements of industrial applications. The groove design also involves thermal management; an appropriate groove shape helps disperse and transfer heat, preventing damage to the sealing faces due to overheating. Therefore, the groove design is a key factor in achieving high efficiency, high reliability, and long service life in mechanical seals.

[0004] Topology optimization is a crucial design method for improving the performance of mechanical seals. It optimizes the distribution of materials within the design space through mathematical modeling and iterative calculations. This method is particularly critical in mechanical seal design because sealing performance largely depends on the configuration of its groove structure. Designers consider multiple objectives and constraints, such as minimizing leakage rate, maximizing opening force, ensuring operational stability, and extending service life, to achieve lightweight structures and efficient material utilization. Researchers have developed various topology optimization techniques, including groove optimization methods based on hydrodynamic principles and triple-accelerated topology optimization processes. These methods significantly improve sealing performance by adjusting helical groove parameters and accelerating the iterative process. With advancements in computational technology, topology optimization has brought innovative solutions to mechanical seal design, not only improving product performance but also achieving dual benefits in terms of economics and the environment. Summary of the Invention

[0005] The purpose of this invention is to propose a mechanical sealing device that can reduce friction and wear on the sealing end face across the entire speed range, reduce leakage without changing the balance film thickness, meet sealing design requirements under multiple operating conditions, and can be applied to various industries such as nuclear power plants.

[0006] A mechanical seal device according to an embodiment of the present invention includes:

[0007] The inner groove is evenly distributed circumferentially in the inner ring area of ​​the sealing end face; the inner groove extends in an L-shape from the inner edge of the sealing end face in the opposite direction of the rotation of the sealing end face, and the inner groove has an outlet at the inner edge of the sealing end face.

[0008] The outer grooves are evenly distributed circumferentially around the sealing end face in the outer ring area of ​​the sealing end face. The overall radial span of the outer grooves is greater than that of the inner grooves. The outer grooves include a first outer groove, a second outer groove, and a third outer groove. The second outer groove and the inner groove are arranged radially correspondingly on the sealing end face. The second outer groove has a first end and a second end circumferentially on the sealing end face. The direction from the first end to the second end is opposite to the rotation direction. The width of the second outer groove gradually decreases from the first end to the second end. The first outer groove and the third outer groove are both located within the outer ring area of ​​the sealing end face. The first end is arranged in a V-shape; the outer first groove extends radially and obliquely in the opposite direction of rotation from the outer edge of the sealing end face to the first end, the outer first groove has an inlet at the outer edge of the sealing end face, one end of the outer first groove and one end of the outer third groove are closely connected to the first end, the other end of the outer third groove and the other end of the outer first groove are radially away from each other and the other end of the outer third groove extends between the outer second groove and the inner groove of a circumferentially adjacent outer groove; the outer first groove, the outer second groove and the outer third groove form a herringbone arrangement.

[0009] The mechanical seal device of this invention has the following advantages: First, it can reduce friction and wear on the sealing end face across the entire speed range, making it universally applicable to various types of mechanical seals. It is suitable for multiple industries such as nuclear power plants, petroleum, chemical, and power, providing strong technical support for the design of sealing groove structures for various rotating equipment. Second, the groove structure of the outer and inner grooves is obtained through topology optimization, maximizing sealing performance and reducing leakage without changing the equilibrium film thickness, thus meeting sealing design requirements under multiple operating conditions. Third, the mechanical seal of the nuclear main pump is crucial to the safe operation and economic benefits of the entire nuclear power plant. Applying the mechanical seal device of this invention to the nuclear main pump mechanical seal can effectively reduce sealing end face wear and leakage, improve the performance of the nuclear main pump mechanical seal, and is of great significance for ensuring the safe and efficient operation of the nuclear power plant.

[0010] In some embodiments, the depth of the outer second groove is less than the depth of the outer first groove and the depth of the outer third groove.

[0011] In some embodiments, the area of ​​the outer second groove is greater than the sum of the areas of the outer first groove and the outer third groove.

[0012] In some embodiments, the first end portion of the outer second groove has a connected first convex profile and a second convex profile, the first convex profile being radially oblique towards the outer edge of the sealing end face, and the second convex profile being radially oblique towards the inner edge of the sealing end face; one end portion of the outer first groove has a first concave profile, and one end portion of the outer third groove has a second concave profile, the first convex profile coincides with the first concave profile, and the second convex profile coincides with the second concave profile; there is a connection point between the first concave profile and the second concave profile, and the connection point between the first convex profile and the second convex profile coincides with the connection point.

[0013] In some embodiments, the outer second groove includes a first profile edge and a second profile edge that are radially opposite to each other; the first profile edge is located between the second profile edge and the outer edge of the sealing end face, the distance between the first profile edge and the second profile edge gradually decreases from the first end to the second end, and the distance from the connection point to the first profile edge is less than the distance from the connection point to the second profile edge.

[0014] The outer first groove includes a third profile edge and a fourth profile edge that are radially opposite to each other; one end of the third profile edge and one end of the fourth profile edge are respectively connected to the first profile edge and the connection point, and the spacing between the third profile edge and the fourth profile edge is the same.

[0015] The outer third groove includes a fifth profile edge and a sixth profile edge that are radially opposite to each other; one end of the fifth profile edge and one end of the sixth profile edge are respectively connected to the second profile edge and the connection point, and the distance between the fifth profile edge and the sixth profile edge decreases from one end of the outer third groove to the other end.

[0016] In some embodiments, the inner groove includes an inner first groove and an inner second groove; the inner second groove extends circumferentially along the sealing end face, the inner first groove extends radially and is connected to the inner second groove, and the inner first groove has the outlet at the inner edge of the sealing end face; the groove depth of the inner second groove is less than the groove depth of the inner first groove.

[0017] In some embodiments, the area of ​​the inner second groove is greater than the area of ​​the inner first groove.

[0018] In some embodiments, the area of ​​the outer groove is larger than the area of ​​the inner groove.

[0019] In some embodiments, the outline of the outer groove is mainly composed of multiple straight edges, and the outline of the inner groove is mainly composed of multiple straight edges.

[0020] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0022] Figure 1 This is a schematic diagram of the initial groove structure of the sealing end face;

[0023] Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of the sealing ring;

[0024] Figure 3 For based on Figure 1 Liquid film pressure cloud map of the end face of the 10° fan-shaped annular groove after optimization of the outer diameter;

[0025] Figure 4 For based on Figure 1 Liquid film pressure cloud map of the end face of the 20° fan-shaped annular groove after optimization of the outer diameter;

[0026] Figure 5 For based on Figure 1 The end face liquid film pressure cloud map of the 20° fan annular surface and the optimized outer diameter side groove shape after reducing the inner edge diameter of the groove area of ​​the outer spiral shallow groove.

[0027] Figure 6 To be Figure 5 A schematic diagram of the simplified curved groove shape;

[0028] Figure 7 For based on Figure 1 Topology optimization was performed to obtain a simplified groove shape diagram on the sealing end face of the sealing mechanical device according to the present invention.

[0029] Figure 8 This is a schematic diagram of the groove shape on the sealing end face of the sealing mechanical device according to an embodiment of the present invention.

[0030] Figure label:

[0031] Inner groove 1; Inner first groove 101; Inner second groove 102; Outer groove 2; Outer first groove 201; First concave contour 2011; Third contour edge 2012; Fourth contour edge 2013; Outer second groove 202; Connection point A; First end 2021; First convex contour 20211; Second convex contour 20212; Second end 2022; First contour edge 2023; Second contour edge 2024; Outer third groove 203; Second concave contour 2031; Fifth contour edge 2032; Sixth contour edge 2033; Inner edge 3; Outer edge 4; Inner spiral shallow groove 5; Outer spiral shallow groove 6; Outer edge of groove area 7; Inner edge of groove area 8; Fan-shaped area 9. Detailed Implementation

[0032] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0033] The following is combined Figures 1 to 8 The mechanical sealing device of the present invention will be described in the following description.

[0034] like Figure 7 and Figure 8 As shown, the mechanical seal device according to an embodiment of the present invention includes an inner groove 1 and an outer groove 2.

[0035] The inner groove 1 is evenly distributed in the inner ring area of ​​the sealing end face along the circumferential direction; the inner groove 1 extends in an L-shape from the inner edge 3 of the sealing end face in the opposite direction of the rotation of the sealing end face, and the inner groove 1 has an outlet at the inner edge 3 of the sealing end face.

[0036] The outer grooves 2 are evenly distributed circumferentially along the sealing end face in the outer ring area of ​​the sealing end face. The overall radial span of the outer grooves 2 is greater than that of the inner grooves 1. The outer grooves 2 include an outer first groove 201, an outer second groove 202, and an outer third groove 203. The outer second groove 202 and the inner groove 1 are arranged radially in a one-to-one correspondence in the sealing end face. The outer second groove 202 has a first end 2021 and a second end 2022 in the circumferential direction of the sealing end face. The direction from the first end 2021 to the second end 2022 is opposite to the direction of rotation. The width of the outer second groove 202 gradually decreases from the first end 2021 to the second end 2022. The outer first groove 201 and the outer third groove 203 are both located in the first ring area of ​​the sealing end face. One end 2021 is arranged in a V-shape; the outer first groove 201 extends radially and obliquely in the opposite direction of rotation from the outer edge 4 of the sealing end face to the first end 2021. The outer first groove 201 has an inlet at the outer edge 4 of the sealing end face. One end of the outer first groove 201 and one end of the outer third groove 203 are closely connected to the first end 2021. The other end of the outer third groove 203 and the other end of the outer first groove 201 are radially far apart from each other, and the other end of the outer third groove 203 extends between the outer second groove 202 and the inner groove 1 of a circumferentially adjacent outer groove 2. The outer first groove 201, the outer second groove 202 and the outer third groove 203 form a herringbone arrangement.

[0037] The outer groove 2 and inner groove 1 on the sealing end face of the mechanical seal device in this embodiment of the invention are based on the common initial groove shape (such as...) on the sealing end face. Figure 1 The topology optimization was performed on the device shown. The topology optimization process is described below to better understand the advantages of the mechanical seal device of this embodiment.

[0038] like Figure 1 As shown, the outer edge 4 of the sealing end face is the inlet high-pressure zone, and the inner edge 3 is the outlet low-pressure zone. The initial groove shape of the sealing end face imitates a spiral groove structure, with an outer spiral shallow groove 6 created near the outer edge 4 of the sealing end face. Simultaneously, imitating the upstream pumping spiral groove structure, an inner spiral shallow groove 5 is created at the inner edge 3 of the sealing end face. The outer spiral shallow groove 6 has a larger area, while the inner shallow groove has a smaller area. For example... Figure 2 As shown, the sealing end face is ground to have a certain taper, and the height of the grinding taper is [missing information]. Meanwhile, by calculating the average height of the inner ring (i.e., the ring between the inner edge 3 of the sealing end face and the outer edge 7 of the groove area of ​​the inner spiral shallow groove 5, with the width of the inner ring being the overall radial span of the inner spiral shallow groove 5) and the average height of the outer ring (i.e., the ring between the outer edge 4 of the sealing end face and the inner edge 8 of the groove area of ​​the outer spiral shallow groove 6, with the width of the outer ring being the overall radial span of the outer spiral shallow groove 6), it is not difficult to find that since the area occupied by the inner spiral shallow groove 5 in the inner ring is much smaller than the area occupied by the outer spiral shallow groove 6 in the outer ring, the overall average height of the inner ring is higher than the average height of the outer ring, which is equivalent to adding an equivalent taper on the basis of the original grinding taper.

[0039] The purpose of the above structural design is as follows: the equivalent taper formed by the grinding taper and groove shape (i.e., the inner spiral shallow groove 5 and the outer spiral shallow groove 6) generates a hydrostatic effect at low and no speeds, making it easier for the rotating and stationary rings to separate and reducing end-face wear between the rotating and stationary rings during the initial stage; the outer spiral shallow groove 6 provides the seal with strong liquid film stiffness at high speeds, improving seal stability; the inner spiral groove provides a certain upstream pumping effect, allowing some fluid to be thrown towards the inlet side, thereby reducing seal leakage. These structural performance characteristics need to be further improved through topology optimization.

[0040] Topology optimization is a method that finds new and better topologies for engineering structures given an objective function and constraints. This method describes these new topologies by introducing a set of design variables, that is, variables describing the presence or absence of materials in the design space. These variables are defined either within each cell of the mesh or at each node of the mesh.

[0041] The relevant topology optimization simulation process for the groove structure of the sealing end face of the mechanical seal device in this embodiment of the invention is as follows: First, the outer spiral shallow groove 6 groove structure is topologically optimized, and its corresponding performance parameters are checked to obtain the optimized groove structure of the outer spiral shallow groove 6, which is the outer groove 2 of the mechanical seal device in this embodiment of the invention; then, the outer groove 2 groove structure is fixed, and the inner spiral shallow groove 5 groove structure is topologically optimized to obtain the optimized groove structure of the inner spiral shallow groove 5, which is the inner groove 1 of the mechanical seal device in this embodiment of the invention. Since the groove shape obtained after topology optimization is complex, after each topology optimization, the contour line method is first used to obtain the shape to take into account the processing requirements, and then the shape is further simplified and checked again.

[0042] The following is about Figure 1 and Figure 2 The optimization process of the outer spiral shallow groove 6 and the inner spiral shallow groove 5 shown is given as a specific example.

[0043] Leakage rate under sealed equilibrium conditions The optimization objective is to determine the equilibrium liquid film thickness. h Not less than Take the opening force In [closing force] 101% closing force Between ] . The optimization problem can be defined as:

[0044]

[0045] In the formula, These are the parameters for the groove structure.

[0046] exist Figure 1 The optimized sector region 9 is defined. The optimized slot shape will differ depending on the angle of the optimized sector region. First, the outer spiral shallow slot 6 is optimized. The angle range of the optimized sector region is 10° and 20°, and the corresponding results are as follows. Figure 3 (First type of groove) and Figure 4 As shown (second type of groove shape). Further reducing the diameter of the inner edge 8 of the outer spiral shallow groove 6 when the fan-shaped region is 20°, the optimization result is as follows: Figure 5 As shown (the third type of slot). Extensive observation of the topology optimization results reveals the following commonalities:

[0047] 1. Each outer spiral shallow groove 6 optimized groove is mainly herringbone shaped. The groove inlet is narrow with a slender tail. The fluid is injected into the sealing end face at an angle along the radial direction. The angle between the injection direction and the radius is relatively large.

[0048] Second, the depth of each outer spiral shallow groove 6 after optimization gradually changes in a regular manner, and the two tail grooves of the herringbone shape are deeper.

[0049] The three optimized trough shapes (i.e., the first, second, and third trough shapes) were processed with contour lines to obtain generalized trough shapes. Finite element simulation calculations were then performed to obtain the relevant equilibrium film thickness and leakage rate parameters, as shown in Table 1.

[0050] Table 1. Sealing performance parameters of three typical groove-shaped structures after optimization.

[0051]

[0052] Taking into account the performance parameters, the third type of groove shape (i.e.) is chosen. Figure 5 Further simplify the process. Select Figure 5 One of the three slot shapes is simplified to form the final structure. Figure 5 The simplified groove shape of one of the three groove shapes (i.e., the outer groove 2 in the embodiment of the present invention) is as follows: Figure 6 As shown in the figure, the corresponding sealing performance parameters are shown in Table 2.

[0053] Table 2. Sealing performance parameters corresponding to the simplified groove shape.

[0054]

[0055] Next, the inner spiral shallow groove 5 is optimized. The goal of optimizing the inner spiral shallow groove 5 is to increase the balance film thickness while simultaneously reducing leakage. At this point, the optimized outer groove 2 needs to be fixed, and topology optimization is performed on the inner spiral shallow groove 5 at the inner annular zone, following the same process as the optimization of the outer spiral shallow groove 6 described above. The final groove shape is as follows. Figure 7 and Figure 8 As shown.

[0056] In summary, the mechanical seal device of this invention has the following advantages: First, it can reduce friction and wear on the sealing end face across the entire speed range, making it universally applicable to various types of mechanical seals. It is suitable for multiple industries such as nuclear power plants, petroleum, chemical, and power, providing strong technical support for the design of sealing groove structures for various rotating equipment. Second, the groove structures of the outer groove 2 and the inner groove 1 are obtained through topology optimization, maximizing sealing performance and reducing leakage without changing the equilibrium film thickness, thus meeting the sealing design requirements under multiple operating conditions. Third, the mechanical seal of the nuclear main pump is crucial to the safe operation and economic benefits of the entire nuclear power plant. Applying the mechanical seal device of this invention to the nuclear main pump mechanical seal can effectively reduce sealing end face wear and leakage, improve the performance of the nuclear main pump mechanical seal, and is of great significance for ensuring the safe and efficient operation of the nuclear power plant.

[0057] In some embodiments, the depth of the outer second groove 202 is less than the depth of the outer first groove 201 and the depth of the outer third groove 203. It is understood that during the topology optimization simulation process for the outer spiral shallow groove 6, except for selecting... Figure 5 One of the three slot shapes is simplified, and... Figure 5 The height variation inside the groove selected for simplification is treated as a stepped groove, that is, the groove depth of the outer second groove 202 is shallow, the groove depth of the outer first groove 201 and the groove depth of the outer third groove 203 are deep. This helps to make the seal have stronger liquid film stiffness when rotating at high speed, improves the stability of the seal, and reduces wear and leakage.

[0058] In some embodiments, the groove depth of the outer second groove 202 is 3-7 mm. The preferred value is 5. The groove depth of the first outer groove 201 is the same as the groove depth of the second outer groove 202, which is 10-14. The preferred values ​​are all 12. This allows the seal to have stronger liquid film stiffness during high-speed rotation, improving seal stability and reducing wear and leakage.

[0059] In some embodiments, the area of ​​the outer second groove 202 is greater than the sum of the areas of the outer first groove 201 and the outer third groove 203. This helps to give the seal stronger liquid film stiffness during high-speed rotation, improves the stability of the seal, and reduces wear and leakage.

[0060] In some embodiments, the first end 2021 of the outer second groove 202 has a connected first convex profile 20211 and a second convex profile 20212. The first convex profile 20211 is radially oblique towards the outer edge 4 of the sealing end face, and the second convex profile 20212 is radially oblique towards the inner edge 3 of the sealing end face. One end of the outer first groove 201 has a first concave profile 2011, and one end of the outer third groove 203 has a second concave profile 2031. The first convex profile 20211 coincides with the first concave profile 2011, and the second convex profile 20212 coincides with the second concave profile 2031. There is a connection point A between the first concave profile 2011 and the second concave profile 2031, and the connection between the first convex profile 20211 and the second convex profile 20212 coincides with connection point A. This is beneficial for the seal to have stronger liquid film stiffness during high-speed rotation, improving the stability of the seal and reducing wear and leakage.

[0061] In some embodiments, the protrusion length of the second protrusion profile 20212 is greater than the protrusion length relative to the first protrusion profile 20211. This facilitates stronger liquid film stiffness of the seal during high-speed rotation, improves seal stability, and reduces wear and leakage.

[0062] In some embodiments, the outer second groove 202 includes a first contour edge 2023 and a second contour edge 2024 that are radially opposite to each other; the first contour edge 2023 is located between the second contour edge 2024 and the outer edge 4 of the sealing end face, the distance between the first contour edge 2023 and the second contour edge 2024 gradually decreases from the first end 2021 to the second end 2022, and the distance from the connection point A to the first contour edge 2023 is less than the distance from the connection point A to the second contour edge 2024.

[0063] The outer first groove 201 includes a third contour edge 2012 and a fourth contour edge 2013 that are radially opposite to each other; one end of the third contour edge 2012 and one end of the fourth contour edge 2013 are respectively connected to the first contour edge 2023 and the connection point A, and the spacing between the third contour edge 2012 and the fourth contour edge 2013 is the same.

[0064] The outer third groove 203 includes a fifth profile edge 2032 and a sixth profile edge 2033 that are radially opposite to each other; one end of the fifth profile edge 2032 and one end of the sixth profile edge 2033 are respectively connected to the second profile edge 2024 and the connection point A, and the distance between the fifth profile edge 2032 and the sixth profile edge 2033 decreases from one end of the outer third groove 203 to the other end.

[0065] This allows the seal to have stronger liquid film stiffness during high-speed rotation, improving the stability of the seal and reducing wear and leakage.

[0066] In some embodiments, the inner groove 1 includes an inner first groove 101 and an inner second groove 102; the inner second groove 102 extends circumferentially along the sealing end face, the inner first groove 101 extends radially and connects to the inner second groove 102, and the inner first groove 101 has an outlet at the inner edge 3 of the sealing end face; the groove depth of the inner second groove 102 is less than the groove depth of the inner first groove 101. This improves the upstream pumping effect, allowing some fluid to be thrown towards the outer edge 4 of the sealing end face, thereby more effectively reducing seal leakage.

[0067] In some embodiments, the groove depth of the inner second groove 202 is 3-7 mm. The depth of the first inner groove 201 is 10-14. This improves the upstream pumping effect, allowing some fluid to be thrown towards the outer edge 4 of the sealing end face, thus more effectively reducing seal leakage.

[0068] In some embodiments, the area of ​​the inner second groove 102 is larger than the area of ​​the inner first groove 101. This is beneficial for improving the upstream pumping effect, allowing some fluid to be thrown towards the outer edge 4 of the sealing end face, thereby more effectively reducing the amount of seal leakage.

[0069] In some embodiments, the area of ​​the outer groove 2 is larger than the area of ​​the inner groove 1. This not only helps to give the seal a stronger liquid film stiffness during high-speed rotation, improving the stability of the seal and reducing wear and leakage, but also helps to improve the upstream pumping effect, allowing some fluid to be thrown towards the outer edge 4 of the sealing end face, thereby more effectively reducing the amount of seal leakage.

[0070] In some embodiments, the sealing end face has a ground taper and an equivalent taper; wherein, the equivalent taper refers to the fact that, because the area occupied by the inner groove 1 in the inner annular zone is much smaller than the area occupied by the outer groove 2 in the outer annular zone, the overall average height of the inner annular zone is higher than the overall average height of the outer annular zone. The ground taper and the superimposed equivalent taper enable the seal to generate a better hydrostatic effect at low speeds and no speeds, making it easier for the rotating ring and stationary ring to separate, and reducing end face wear between the rotating ring and stationary ring during the initial stage.

[0071] In some embodiments, the outline of the outer groove 2 is mainly composed of multiple straight edges, and the outline of the inner groove 1 is mainly composed of multiple straight edges. This better meets the processing requirements and facilitates processing.

[0072] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. 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, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0073] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A mechanical seal device, characterized in that, include: The inner groove is evenly distributed circumferentially in the inner ring area of ​​the sealing end face; the inner groove extends in an L-shape from the inner edge of the sealing end face in the opposite direction of the rotation of the sealing end face, and the inner groove has an outlet at the inner edge of the sealing end face. The outer grooves are evenly distributed circumferentially around the sealing end face in the outer ring area of ​​the sealing end face. The overall radial span of the outer grooves is greater than that of the inner grooves. The outer grooves include a first outer groove, a second outer groove, and a third outer groove. The second outer groove and the inner groove are arranged radially correspondingly on the sealing end face. The second outer groove has a first end and a second end circumferentially on the sealing end face. The direction from the first end to the second end is opposite to the rotation direction. The width of the second outer groove gradually decreases from the first end to the second end. The first outer groove and the third outer groove are both located within the outer ring area of ​​the sealing end face. The first end is arranged in a V-shape; the outer first groove extends radially and obliquely in the opposite direction of rotation from the outer edge of the sealing end face to the first end, the outer first groove has an inlet at the outer edge of the sealing end face, one end of the outer first groove and one end of the outer third groove are closely connected to the first end, the other end of the outer third groove and the other end of the outer first groove are radially away from each other and the other end of the outer third groove extends between the outer second groove and the inner groove of a circumferentially adjacent outer groove; the outer first groove, the outer second groove and the outer third groove form a herringbone arrangement.

2. The mechanical seal device according to claim 1, characterized in that, The depth of the second outer groove is less than the depth of the first outer groove and the depth of the third outer groove.

3. The mechanical seal device according to claim 2, characterized in that, The area of ​​the second outer groove is greater than the sum of the areas of the first outer groove and the third outer groove.

4. The mechanical seal device according to claim 2, characterized in that, The first end portion of the outer second groove has a connected first convex profile and a second convex profile. The first convex profile is radially oblique towards the outer edge of the sealing end face, and the second convex profile is radially oblique towards the inner edge of the sealing end face. One end portion of the outer first groove has a first concave profile, and one end portion of the outer third groove has a second concave profile. The first convex profile coincides with the first concave profile, and the second convex profile coincides with the second concave profile. There is a connection point between the first concave profile and the second concave profile, and the connection point between the first convex profile and the second convex profile coincides with the connection point.

5. The mechanical seal device according to claim 4, characterized in that, The outer second groove includes a first profile edge and a second profile edge that are radially opposite to each other; the first profile edge is located between the second profile edge and the outer edge of the sealing end face, the distance between the first profile edge and the second profile edge gradually decreases from the first end to the second end, and the distance from the connection point to the first profile edge is less than the distance from the connection point to the second profile edge. The outer first groove includes a third profile edge and a fourth profile edge that are radially opposite to each other; one end of the third profile edge and one end of the fourth profile edge are respectively connected to the first profile edge and the connection point, and the spacing between the third profile edge and the fourth profile edge is the same. The outer third groove includes a fifth profile edge and a sixth profile edge that are radially opposite to each other; one end of the fifth profile edge and one end of the sixth profile edge are respectively connected to the second profile edge and the connection point, and the distance between the fifth profile edge and the sixth profile edge decreases from one end of the outer third groove to the other end.

6. The mechanical seal device according to claim 1, characterized in that, The inner groove includes an inner first groove and an inner second groove; the inner second groove extends circumferentially along the sealing end face, the inner first groove extends radially and connects to the inner second groove, and the inner first groove has the outlet at the inner edge of the sealing end face; the groove depth of the inner second groove is less than the groove depth of the inner first groove.

7. The mechanical seal device according to claim 6, characterized in that, The area of ​​the second inner groove is greater than the area of ​​the first inner groove.

8. The mechanical seal device according to any one of claims 1-7, characterized in that, The area of ​​the outer groove is larger than the area of ​​the inner groove.

9. The mechanical seal device according to any one of claims 1-7, characterized in that, The outer groove's outline is mainly composed of multiple straight edges, and the inner groove's outline is also mainly composed of multiple straight edges.

Images