Mechanical seal friction pair

Abstract

The invention belongs to the technical field of mechanical sealing, and discloses a mechanical sealing friction pair. The mechanical sealing friction pair comprises a static ring and a moving ring, the static ring is provided with a first sealing part, and the first sealing part is provided with a first sealing surface; the movable ring can rotate relative to the static ring, the movable ring is provided with a second sealing part, and the second sealing part is provided with a second sealing surface; a plurality of crossed grooves are concavely formed in the second sealing surface of the second sealing part at intervals, each crossed groove comprises a first groove and a second groove which are arranged in a crossed manner, and inlets of the first grooves and inlets of the second grooves are arranged at intervals and penetrate through the side wall of the outer diameter side of the second sealing part; the tail end of the first groove and the tail end of the second groove are both located between the inner diameter side and the outer diameter side of the second sealing part. A plurality of communicating grooves are concavely formed in the second sealing face of the second sealing part at intervals, and the two ends of each communicating groove communicate with the two adjacent cross grooves correspondingly. The mechanical sealing friction pair can reduce deposition of residues in a launder, is high in sealing performance and service life, and can meet the requirements of the working condition of bidirectional rotation.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical seals, and in particular to a mechanical seal friction pair. Background Art

[0002] Non-contact mechanical seal is a type of mechanical seal. In this type of mechanical seal, a flow groove is opened on the end face of the friction pair. When the friction pair is running, the sealing isolation fluid flows in the groove due to the flow groove, generating fluid dynamic pressure. The generated fluid dynamic pressure causes the sealing isolation fluid to form a liquid film with extremely high rigidity. The axial opening force formed by the liquid film is balanced with the axial closing force formed by the external spring force, thereby achieving sealing in a non-contact state.

[0003] As the market demand for high-purity quality of chemical products increases, the requirements for operating temperature, pressure and mechanical seal friction pairs in the chemical reaction process are also increasing. When the friction pair of the prior art is in operation, the sealing isolation fluid is in contact with the flow channel for a long time, which may cause the groove wall of the flow channel to peel off and produce residues. These residues may not be discharged in the flow channel, affecting the sealing performance and service life of the mechanical seal friction pair. Therefore, it is urgent to design a mechanical seal friction pair to meet the higher requirements for the sealing performance and service life of the mechanical seal friction pair in the reaction equipment. Summary of the invention

[0004] The object of the present invention is to provide a mechanical seal friction pair, which can reduce the deposition of residues in the flow groove, improve the sealing performance and service life of the mechanical seal friction pair, and further, can meet the requirements of bidirectional rotation working conditions.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A mechanical seal friction pair, comprising:

[0007] A stationary ring, wherein the stationary ring is provided with a first sealing portion, and the first sealing portion is provided with a first sealing surface;

[0008] A dynamic ring, which can rotate relative to the static ring, and is provided with a second sealing part, and the second sealing part is provided with a second sealing surface; the second sealing surface can contact or stay away from the first sealing surface; the second sealing part is provided with a plurality of intersecting grooves at intervals on the second sealing surface, and the intersecting grooves include a first groove and a second groove arranged in an intersecting manner, and the inlet of the first groove and the inlet of the second groove are arranged at intervals and both pass through the side wall of the outer diameter side of the second sealing part; the end of the first groove and the end of the second groove are both located between the inner diameter side and the outer diameter side of the second sealing part; the second sealing part is also provided with a plurality of connecting grooves at intervals on the second sealing surface, and the two ends of the connecting grooves are respectively connected with two adjacent intersecting grooves.

[0009] In some possible implementations, the intersection point of the cross groove is located at a middle position of the first groove and at a middle position of the second groove.

[0010] In some possible implementations, one end of the connecting groove is connected to the end of the first groove of one of the intersecting grooves, and the other end of the connecting groove is connected to the end of the second groove of another adjacent intersecting groove.

[0011] In some possible implementations, the material of the dynamic ring is zirconium oxide, and the material of the static ring is silicon carbide.

[0012] In some possible implementations, the second sealing surface is divided into three planar areas with equal spacing along the radial direction. The three planar areas are the first planar area, the second planar area and the third planar area from the inside to the outside, and the cross groove covers the second planar area and the third planar area.

[0013] In some possible implementations, the communicating groove covers the second plane area.

[0014] In some possible implementations, the width of the connecting groove is greater than the width of the intersecting groove.

[0015] In some possible implementations, the six cross grooves are evenly spaced on the second sealing surface, the three connecting grooves are evenly spaced on the second sealing surface, and both ends of each connecting groove are respectively connected to two adjacent cross grooves.

[0016] In some possible embodiments, the line connecting the intersection of the cross groove and the midpoint of the moving ring is a symmetry line, the cross groove is a symmetrical structure and is symmetrically distributed relative to the symmetry line, and the shapes of multiple cross grooves are the same, and the shapes of multiple connecting grooves are the same.

[0017] In some possible implementations, the paths of the first groove, the second groove, and the connecting groove are all arc lines.

[0018] Beneficial effects of the present invention:

[0019] The mechanical seal friction pair provided by the present invention comprises a stationary ring and a dynamic ring, wherein the second sealing portion is provided with a second sealing surface, and the second sealing portion is provided with a plurality of intersecting grooves at intervals on the second sealing surface, wherein the intersecting grooves comprise a first groove and a second groove arranged in an intersecting manner, and the intersecting grooves are provided so that a sealing isolation fluid can flow in the grooves to generate fluid dynamic pressure and achieve sealing.

[0020] The outer diameter side of the second sealing part is the high pressure side, and the inner diameter side is the low pressure side. The sealing isolation fluid can flow into the first groove from the inlet of the first groove, that is, from the high pressure side, or flow into the second groove from the inlet of the second groove, that is, from the high pressure side. The second sealing part is also provided with a plurality of connecting grooves at intervals at the second sealing surface, and the two ends of the connecting grooves are respectively connected with the ends of the two adjacent cross grooves, so that the residue in the first groove can be discharged out of the groove through the second groove or the connecting groove, so that the residue in the second groove can be discharged out of the groove through the first groove or the connecting groove, which can reduce the deposition of the residue in the flow groove, improve the sealing performance and service life of the mechanical seal friction pair, and set the first groove to meet the liquid inlet demand of the moving ring rotating clockwise, and set the second groove to meet the liquid inlet demand of the moving ring rotating counterclockwise. The end of the first groove and the end of the second groove are both located between the inner diameter side and the outer diameter side of the second sealing part, which can prevent the sealing isolation fluid from flowing out from the low pressure side and causing leakage of the sealing isolation fluid.

[0021] In addition, by providing the connecting groove, the axial opening force can be increased, the wear between the dynamic ring and the static ring sealing surface can be reduced, and the service life of the mechanical seal friction pair can be further improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the assembly structure of the dynamic ring and the static ring provided by the present invention;

[0023] Figure 2 is an axonometric view of the dynamic ring involved in the present invention;

[0024] Figure 3 is a bottom view of the moving ring involved in the present invention;

[0025] Figure 4 It is a partial structural schematic diagram of the dynamic ring involved in the present invention;

[0026] Figure 5 yes Figure 4 A partial enlarged view at point A.

[0027] In the figure:

[0028] 1. static ring; 11. first sealing part; 111. first sealing surface;

[0029] 2. Moving ring; 21. Second sealing part; 211. Second sealing surface; 2111. First plane area; 2112. Second plane area; 2113. Third plane area; 22. Cross groove; 221. First groove; 222. Second groove; 23. Connecting groove. DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0031] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0033] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0034] like Figures 1 to 5As shown, the present invention provides a mechanical seal friction pair, including a stationary ring 1 and a dynamic ring 2, the stationary ring 1 is provided with a first sealing portion 11, and the first sealing portion 11 is provided with a first sealing surface 111; the dynamic ring 2 can rotate relative to the stationary ring 1, and the dynamic ring 2 is provided with a second sealing portion 21, and the second sealing portion 21 is provided with a second sealing surface 211; the second sealing surface 211 can contact or stay away from the first sealing surface 111; the second sealing portion 21 is recessed with a plurality of intersecting grooves 22 at intervals on the second sealing surface 211, and the intersecting grooves 22 include a first groove 221 and a second groove 222 arranged in an intersecting manner, and the inlet of the first groove 221 and the inlet of the second groove 222 are arranged at intervals and both penetrate the side wall of the outer diameter side of the second sealing portion 21; the end of the first groove 221 and the end of the second groove 222 are both located between the inner diameter side and the outer diameter side of the second sealing portion 21; the second sealing portion 21 is also recessed with a plurality of connecting grooves 23 at intervals on the second sealing surface 211, and the two ends of the connecting grooves 23 are respectively connected with two adjacent intersecting grooves 22.

[0035] By setting the cross groove 22, the sealing isolation liquid can flow in the groove, generate fluid dynamic pressure, and achieve sealing. During operation, the outer diameter side of the second sealing part 21 is the high-pressure side, and the inner diameter side is the low-pressure side. The sealing isolation liquid flows from the high-pressure side to the low-pressure side. Specifically, it can flow into the first groove 221 from the inlet of the first groove 221, or flow into the second groove 222 from the inlet of the second groove 222. A plurality of connecting grooves 23 are recessed at intervals on the second sealing surface 211 of the second sealing part 21. The two ends of the connecting groove 23 are respectively connected to the two adjacent cross grooves 22. After the sealing isolation liquid flows in from the inlet of the first groove 221, the residue in the first groove 221 can be discharged through the inlet of the second groove 222. The sealing isolation liquid flows into the second groove 222 from the inlet, so that the residue in the second groove 222 can be discharged from the groove through the inlet of the first groove 221 or the inlet of the adjacent cross groove 22 through the connecting groove 23, thereby reducing the deposition of residue in the flow groove and improving the sealing performance and service life of the mechanical seal friction pair. In addition, the first groove 221 is provided to meet the liquid inlet demand of the moving ring 2 for clockwise rotation, and the second groove 222 is provided to meet the liquid inlet demand of the moving ring 2 for counterclockwise rotation, thereby meeting the bidirectional rotation working condition.

[0036] The ends of the first groove 221 and the second groove 222 are both located between the inner diameter side and the outer diameter side of the second sealing portion 21, which can prevent the sealing isolation fluid from flowing out from the low-pressure side and causing leakage of the sealing isolation fluid. In addition, by providing the connecting groove 23, the liquid inlet volume can be increased, thereby increasing the axial opening force, reducing the wear between the sealing surfaces of the dynamic ring 2 and the static ring 1, and further improving the service life of the mechanical seal friction pair.

[0037] Optionally, in this embodiment, six cross grooves 22 are evenly spaced on the second sealing surface 211, three connecting grooves 23 are evenly spaced on the second sealing surface 211, and the two ends of each connecting groove 23 are respectively connected to two adjacent cross grooves 22. Such a configuration can avoid excessive axial opening force and increase the leakage of the sealing isolation fluid. In other embodiments, six cross grooves 22 and six connecting grooves 23 are each provided, and the six cross grooves 22 and the six connecting grooves 23 are evenly spaced on the second sealing surface 211, and the two ends of each connecting groove 23 are respectively connected to two adjacent cross grooves 22; specifically, the number of cross grooves 22 and connecting grooves 23 and whether the two ends of a single cross groove 22 are both provided with connecting grooves 23, or the connecting groove 23 is only provided at one end can be adjusted according to the pressure applied to the sealing isolation fluid by the high-pressure side and the axial closing force formed by the external spring force.

[0038] Optionally, in this embodiment, the line connecting the intersection of the cross groove 22 and the midpoint of the dynamic ring 2 is a symmetry line, the cross groove 22 is a symmetrical structure and is symmetrically distributed relative to the symmetry line, and the shapes of multiple cross grooves 22 are the same, and the shapes of multiple connecting grooves 23 are the same, which can ensure that the axial opening force between the dynamic ring 2 and the static ring 1 is uniform.

[0039] Optionally, in this embodiment, the paths of the first groove 221, the second groove 222 and the connecting groove 23 are all arc lines, which can make the sealing isolation liquid flow better during the rotation of the dynamic ring 2 and are more convenient to process. Furthermore, the centers of the arc lines of the first groove 221, the second groove 222 and the connecting groove 23 are all set toward the center of the dynamic ring 2, which plays a guiding role, and facilitates the entry of the sealing isolation liquid on the high-pressure side when the dynamic ring 2 rotates.

[0040] Optionally, in this embodiment, the intersection of the cross groove 22 is located at the middle position of the first groove 221 and at the middle position of the second groove 222. In this way, the sealing isolation liquid flowing into the second groove 222 from the open end of the second groove 222 can not only flow into the open end of the first groove 221 through the intersection, but also continue to flow into the second groove 222 at the end portion through the intersection, thereby preventing the sealing isolation liquid from directly flowing from the open end of the second groove 222 into the open end of the first groove 221, thereby causing the axial opening force to be too small. Similarly, the sealing isolation liquid flowing into the first groove 221 from the open end of the first groove 221 can not only flow into the open end of the second groove 222 through the intersection, but also continue to flow into the first groove 221 at the end portion through the intersection, thereby preventing the sealing isolation liquid from directly flowing from the open end of the first groove 221 into the open end of the second groove 222, thereby causing the axial opening force to be too small.

[0041] Further, one end of the connecting groove 23 is connected to the end of the first groove 221 of one cross groove 22, and the other end of the connecting groove 23 is connected to the end of the second groove 222 of another adjacent cross groove 22. Such an arrangement facilitates the guidance of the residue and is simple to process. Of course, in other embodiments, one end of the connecting groove 23 can also be connected to the end of the first groove 221 and the end of the second groove 222 in one cross groove 22, and the other end of the connecting groove 23 can be connected to the end of the first groove 221 and the end of the second groove 222 in another adjacent cross groove 22, so that the residue in the flow channel can be discharged.

[0042] Optionally, in this embodiment, the material of the moving ring 2 is zirconium oxide, and the material of the stationary ring 1 is silicon carbide. First, the moving ring 2 and the stationary ring 1 are made of different materials, which can balance the hardness and strength of the materials. Zirconium oxide has higher strength than silicon carbide, is not prone to brittle edge collapse, has a low expansion coefficient, is resistant to high temperatures, and has certain lubricity, while silicon carbide has higher hardness than zirconium oxide and better wear resistance. The moving ring 2 of this embodiment adopts zirconium oxide, which solves the edge collapse problem existing in the prior art when the moving ring 2 adopts silicon carbide. In this embodiment, due to the different hardness of silicon carbide and zirconium oxide, when the moving ring 2 rotates, the wear on the moving ring 2 is greater, and the wear on the stationary ring 1 is less, which reduces the friction work and wear between the sealing surfaces. When replacing, only the moving ring 2 can be replaced. Therefore, compared with the conventional moving ring 2 and the stationary ring 1, the material is both silicon carbide, or the moving ring 2 is graphite, and the stationary ring 1 is silicon carbide. The combination is more advantageous.

[0043] Optionally, in this embodiment, if Figure 4 As shown, the second sealing surface 211 is divided into three plane areas with equal intervals along the radial direction. The three plane areas are the first plane area 2111, the second plane area 2112 and the third plane area 2113 from the inside to the outside. The cross groove 22 covers the second plane area 2112 and the third plane area 2113. While preventing the sealing isolation fluid from leaking from the low-pressure side, it can ensure that the axial opening force between the sealing surfaces is relatively balanced.

[0044] Optionally, in this embodiment, the connecting groove 23 covers the second plane area 2112. Since the second plane area 2112 is located in the middle of the second sealing surface 211, the connecting groove 23 covers the second plane area 2112, so that the axial opening force between the sealing surfaces is more balanced, and the uneven distribution of the opening force causes the dynamic ring 2 to tilt, so that the sealing isolation liquid is leaked excessively. Optionally, in this embodiment, the groove width of the connecting groove 23 is greater than the groove width of the cross groove 22 to increase the axial opening force and reduce the wear between the sealing surfaces. Furthermore, the groove depth of the connecting groove 23 is greater than the groove depth of the cross groove 22, which can further increase the axial opening force. Specifically, in this embodiment, the groove depth of the cross groove 22 is 50μm, and the groove width is 100μm; the groove depth of the connecting groove 23 is 75μm, and the groove width is 150μm.

[0045] Specifically, in this embodiment, the outer diameter of the second sealing surface 211 is 242 mm, the inner diameter is 230 mm, the outer diameter of the first plane area 2111 is 234 mm, the outer diameter of the second plane area 2112 is 238 mm, the vertical distance from the center of the arc line of the first groove 221 to the center of the moving ring 2 is 12.5 mm, the horizontal distance is 22 mm, the vertical distance from the center of the arc line of the second groove 222 to the center of the moving ring 2 is 25 mm, the horizontal distance is 0 mm, the radius R1 of the first groove 221 and the radius R2 of the second groove 222 are both 99 mm, the vertical distance from the center of the arc line of the connecting groove 23 to the center of the moving ring 2 is 25 mm, the horizontal distance is 0 mm, and the radius R3 of the first groove 221 is 93.889 mm. Such a setting can meet the requirements that the cross groove 22 covers the second plane area 2112 and the third plane area 2113, and the connecting groove 23 covers the second plane area 2112.

[0046] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A mechanical seal friction pair, characterized in that: include: A stationary ring (1), wherein the stationary ring (1) is provided with a first sealing portion (11), and the first sealing portion (11) is provided with a first sealing surface (111); A dynamic ring (2), the dynamic ring (2) being rotatable relative to the static ring (1), the dynamic ring (2) being provided with a second sealing portion (21), the second sealing portion (21) being provided with a second sealing surface (211); the second sealing surface (211) being able to contact or be away from the first sealing surface (111); the second sealing portion (21) being provided with a plurality of intersecting grooves (22) at intervals on the second sealing surface (211), the intersecting grooves (22) comprising a first groove (221) and a second groove (222) arranged in an intersecting manner, The inlet of the first groove (221) and the inlet of the second groove (222) are arranged at intervals and both pass through the side wall of the outer diameter side of the second sealing part (21); the end of the first groove (221) and the end of the second groove (222) are both located between the inner diameter side and the outer diameter side of the second sealing part (21); the second sealing part (21) is also provided with a plurality of connecting grooves (23) at intervals on the second sealing surface (211), and the two ends of the connecting grooves (23) are respectively connected to two adjacent cross grooves (22).

2. The mechanical seal friction pair according to claim 1, characterized in that: The intersection point of the cross groove (22) is located at the middle position of the first groove (221) and at the middle position of the second groove (222).

3. The mechanical seal friction pair according to claim 2, characterized in that: One end of the connecting groove (23) is connected to the end of the first groove (221) of one of the intersecting grooves (22), and the other end of the connecting groove (23) is connected to the end of the second groove (222) of another adjacent intersecting groove (22).

4. The mechanical seal friction pair according to claim 1, characterized in that: The material of the dynamic ring (2) is zirconium oxide, and the material of the static ring (1) is silicon carbide.

5. The mechanical seal friction pair according to claim 1, characterized in that: The second sealing surface (211) is divided into three plane areas at equal intervals along the radial direction. The three plane areas are, from the inside to the outside, a first plane area (2111), a second plane area (2112) and a third plane area (2113), and the cross groove (22) covers the second plane area (2112) and the third plane area (2113).

6. The mechanical seal friction pair according to claim 5, characterized in that: The connecting groove (23) covers the second plane area (2112).

7. The mechanical seal friction pair according to claim 1, characterized in that: The groove width of the connecting groove (23) is greater than the groove width of the intersecting groove (22).

8. The mechanical seal friction pair according to any one of claims 1 to 7, characterized in that: The six intersecting grooves (22) are distributed at equal intervals on the second sealing surface (211), the three connecting grooves (23) are distributed at equal intervals on the second sealing surface (211), and the two ends of each connecting groove (23) are respectively connected to two adjacent intersecting grooves (22).

9. The mechanical seal friction pair according to any one of claims 1 to 7, characterized in that: The line connecting the intersection of the cross groove (22) and the midpoint of the moving ring (2) is a symmetry line, the cross groove (22) is a symmetrical structure and is symmetrically distributed relative to the symmetry line, and the shapes of the plurality of cross grooves (22) are the same, and the shapes of the plurality of connecting grooves (23) are the same.

10. The mechanical seal friction pair according to any one of claims 1 to 7, characterized in that: The paths of the first groove (221), the second groove (222) and the connecting groove (23) are all arc lines.

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