Mechanical seal end face with drainage groove structure and mechanical seal

Abstract

A mechanical seal end face with a drainage groove structure and a mechanical seal comprise a rotating ring and a static ring which are used for sealing the mechanical end face, the rotating ring and the static ring are both provided with annular sealing end faces which are coaxially arranged, and the sealing end faces take the circle center of the sealing ring as the reference. An outer side sealing face, an annular groove and an inner side sealing face are sequentially arranged in the radial direction from the outer edge to the circle center. Drainage grooves distributed in the circumferential direction are formed in the outer side sealing face and penetrate through the whole outer side sealing face, the inlet ends of the drainage grooves are connected with the medium side, and the outlet ends of the drainage grooves are connected with the annular groove. When the rotating ring rotates, a medium enters the drainage groove from the inlet end of the drainage groove and then flows into the ring groove from the outlet end. Through the drainage groove, the pressure of a medium in the annular groove can be greatly improved, the medium can be effectively supplemented to the inner side sealing face, the continuity of formation of a liquid film on the inner side sealing face is ensured, and dry friction of the inner side sealing face and flash evaporation of the medium caused by too high temperature are avoided.

Description

Technical Field

[0001] The present invention relates to the field of mechanical seals, and more particularly to a mechanical seal end face with a drainage groove structure and a mechanical seal, which are applicable to the sealing devices of various automotive water pumps, and more specifically, to the rotary mechanical seal device between the pump shaft and the pump hole of the water pump. Background Art

[0002] Mechanical seals are widely used in rotary equipment such as pumps, compressors, reactors, agitators, centrifuges, and filters for transporting or processing various fluids. In a mechanical seal, the rotating seal ring rotates with the shaft and closely fits with the stationary seal ring to form the main seal to prevent the leakage of the sealed medium.

[0003] In the conventional mechanical seal end face structure, due to the throttling or centrifugal force of the sealing surface gap, the medium pressure decreases linearly or non-linearly from the medium side to the atmosphere side, so that the inner sealing surface cannot be lubricated sufficiently by the medium. In addition, in order to reduce the wear amount of the seal end face and avoid the wear of the medium impurities and achieve a higher service life, for the rotary friction pair of the mechanical seal composed of the rotating ring and the stationary ring, engineers have developed the paired type of double silicon carbide seal rings and the paired type of ceramic and carbon graphite seal rings. Since silicon carbide has no self-lubricating property, more heat will be generated during operation, so that the paired type of double silicon carbide seal rings is more likely to cause the medium flashing phenomenon on the inner side of the seal end face than the paired type of ceramic and carbon graphite seal rings, resulting in poor lubrication and dry friction wear on the inner side of the seal end face.

[0004] The lubrication of the seal end face can be enhanced by opening shallow grooves on the flat end face of the seal ring, reducing the friction and wear on the end face, reducing the frictional heat, and improving the stability and life of the seal. At present, the mechanical seal with shallow grooves opened on the end face has developed into a typical non-contact mechanical seal. This non-contact mechanical seal is to open a series of shallow grooves with a depth of micron level on the flat end face of one of the seal rings, such as spiral grooves, arc grooves, leaf-shaped grooves, T-shaped grooves, Y-shaped grooves, L-shaped grooves, straight grooves, and various special-shaped grooves. During operation, due to the hydrodynamic effect of the shallow grooves, the pressure of the sealing fluid entering the grooves is increased, and this pressure acts on the sealing end faces of the moving and stationary rings that are in contact with each other, pushing these two faces apart and not in contact, and forming a continuous and stable thin film of the sealing fluid between them to achieve non-contact sealing.

[0005] The shallow grooves are generally opened on the sealing end faces of hard seal rings such as tungsten carbide, silicon carbide, and silicon nitride. High-precision machining is relatively difficult, but their geometric shapes have a great influence on the thickness, stiffness, load-bearing capacity, and stability of the fluid film. Good shallow groove geometric shape design and high-precision machining are the core technologies of mechanical seals.

[0006] The known seal ring with shallow grooves provided on the seal end face still has deficiencies.

[0007] For example, ordinary flat-bottomed equal-depth spiral grooves, arc grooves, leaf-shaped grooves, T-shaped grooves, Y-shaped grooves, L-shaped grooves, and various special-shaped grooves, due to the equal groove depth, do not strongly compress the sealing fluid, and the hydrodynamic pressure effect is not strong. Therefore, under certain working conditions, the thickness of the fluid film is insufficient, or the stiffness of the fluid film is insufficient at a certain fluid film thickness, resulting in unstable sealing performance.

[0008] One of the main development directions of mechanical seals is to enhance the hydrodynamic pressure effect of the end-face fluid by opening non-equal-depth shallow grooves on the sealing end-face of the sealing ring, thereby increasing the load-bearing capacity and stiffness of the end-face fluid film, improving the operating stability and reliability of the seal, and extending the service life.

[0009] The invention application with the publication number CN111520477A discloses a mechanical seal end-face structure similar to the shape of the Bagua diagram. This invention has good sealing performance and can effectively solve the flashing problem. However, the non-equal-depth groove structure of this invention is fine and has high precision, strict roughness requirements, and general machinability, making normal processing very difficult. Summary of the Invention

[0010] In view of this, the purpose of the present invention is to provide a mechanical seal end-face and a mechanical seal with a drainage groove structure, which can greatly increase the pressure of the medium in the ring groove while being easy to process, more effectively supplement the medium to the inner sealing surface, ensure the continuity of the formation of the liquid film on the inner sealing surface, avoid dry friction on the inner sealing surface, and avoid flashing of the medium due to excessive temperature on the inner sealing surface.

[0011] A mechanical seal end-face with a drainage groove structure includes a rotating ring and a stationary ring for mechanical end-face sealing. The rotating ring and the stationary ring together form a friction pair. The characteristic is that both the rotating ring and the stationary ring have coaxially arranged annular sealing end-faces. Based on the center of the sealing ring, the following are sequentially arranged along the radial direction from the outer edge to the center of the circle on the sealing end-face: an outer sealing surface, a ring groove, and an inner sealing surface;

[0012] The outer sealing surface is provided with drainage grooves distributed along the circumferential direction. The drainage grooves penetrate the entire outer sealing surface, with the inlet end connected to the medium side and the outlet end connected to the ring groove.

[0013] The depth of the drainage groove is 15 μm to 60 μm, and the width is 0.15 mm to 0.20 mm;

[0014] The width of the ring groove is 0.4 to 1.2 times (1 time means equal width to the width of the outer sealing surface) the width of the outer sealing surface, and the width of the inner sealing surface is 0.5 to 1.5 times the width of the outer sealing surface.

[0015] Further, the drainage grooves are evenly distributed in the circumferential direction, and the number thereof is 20 to 30.

[0016] Further, the drainage groove has a certain angle α with the center line, and the angle is between 45° and 60°.

[0017] Further, the wall of the drainage groove is a plane or an arc surface; when the wall of the drainage groove adopts an arc surface, the arc of the wall of the drainage groove faces the medium side direction.

[0018] Further, the wall of the drainage groove is preferably perpendicular to the sealing end face or the angle with the sealing end face is within 10°.

[0019] Further, the drainage grooves are of equal depth, and the depth is 15 μm to 60 μm; or, the drainage grooves are arranged with gradually increasing depth from the inlet end to the outlet end, the depth of the inlet end is 15 μm to 50 μm, the depth of the outlet end is 20 μm to 60 μm, and the depth of the inlet end is 5 μm to 10 μm larger than that of the outlet end.

[0020] Further, it is characterized in that the drainage grooves are of equal width, and the width is 0.15 mm to 0.20 mm; or, the width of the drainage grooves gradually increases from the inlet end to the outlet end, the width of the inlet end is 0.15 mm to 0.20 mm, the width of the outlet end is 0.20 mm to 0.25 mm, and the width of the inlet end is 0.05 mm to 0.10 mm larger than that of the outlet end.

[0021] Further, a transition arc is provided at the connection between the outlet end of the drainage groove and the annular groove. The transition arc can smooth the connection between the drainage groove and the annular groove, reduce the sudden turning of the medium flow, reduce the local pressure loss, and improve the uniformity of the pressure distribution in the annular groove.

[0022] Further, a chamfer structure is provided at the inlet end of the drainage groove. The chamfer direction of the chamfer structure is consistent with the medium flow direction. The chamfer structure can effectively reduce the turbulence and local resistance when the medium enters the drainage groove, prevent impurity jamming, and improve the medium introduction efficiency.

[0023] Further, a mechanical seal is provided, and the mechanical seal adopts the above mechanical seal end face structure.

[0024] The present invention has the following advantages:

[0025] 1. Through the design of the drainage grooves on the seal end face, the pressure of the medium in the annular groove can be greatly increased during the operation of the mechanical seal, the medium can be more effectively supplemented to the inner seal face, the continuity of the liquid film formation on the inner seal face can be ensured, dry friction on the inner seal face can be avoided, and flash evaporation of the medium caused by too high temperature on the inner seal face can be avoided.

[0026] 2. Through the design of the drainage groove on the sealing end face, when small particle impurities enter the drainage groove, the impurities will not get stuck in the drainage groove and can smoothly enter the annular groove, effectively preventing the impurities from entering the outer sealing end face through the notch at the inlet end of the drainage groove.

[0027] 3. The drainage groove described in the present invention is a plane or an arc surface, with a simple shape. It can be processed by laser etching or die pressing, and the processing steps are simple and the processing accuracy is high.

[0028] 4. By expanding the width ratio range of the annular groove and the inner sealing surface (0.4 - 1.2 times, 0.5 - 1.5 times), a wider range of working conditions can be adapted, applicable to both low-flow compact devices and high-flow high-pressure systems; dynamic performance can be optimized, and the drainage efficiency, pressure buffering, and lubrication effect can be balanced through ratio adjustment; at the same time, the cost and performance are balanced, reducing material use or improving energy efficiency in specific scenarios while maintaining the core sealing function. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 An isometric view of the sealing ring given by the present invention;

[0030] Figure 2 A partially enlarged view of the position of the drainage groove of the sealing ring;

[0031] Figure 3 A view of the arc orientation when the groove wall of the drainage groove of the sealing ring is an arc surface;

[0032] Figure 4 A schematic diagram of the equal-depth and equal-width structure of Embodiment 1 proposed by the present invention;

[0033] Figure 5 A schematic diagram of the equal-depth and gradually-widening structure of Embodiment 3 proposed by the present invention;

[0034] Figure 6 A schematic diagram of the gradually-deepening and equal-width structure of Embodiment 5 proposed by the present invention;

[0035] Figure 7 A schematic diagram of the gradually-deepening and gradually-widening structure of Embodiment 7 proposed by the present invention; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] In order to more clearly understand the above-mentioned objects, features, and advantages of the present disclosure, the solutions of the present invention will be further described below. It should be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0037] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention may be practiced in other ways than those described herein. Obviously, the embodiments in the specification are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0038] To facilitate an understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. Embodiments of the present invention are shown in the drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided so that the disclosure of the present application will be thorough and complete.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this invention belongs. The terms used herein in the specification are for the purpose of describing particular embodiments only and are not intended to limit the present application.

[0040] Embodiment 1

[0041] As Figure 1 shown, a mechanical seal end face with a drainage groove structure and a mechanical seal include a rotating ring and a stationary ring for mechanical end face sealing. It is characterized in that both the rotating ring and the stationary ring have a sealing end face. The sealing end face of the sealing ring is sequentially provided with, starting from the outside to the center of the sealing ring: an outer sealing surface 1, a ring groove 2, and an inner sealing surface 3.

[0042] As Figure 2 shown, the outer sealing surface 1 is provided with drainage grooves 4 distributed in the circumferential direction. The drainage grooves 4 penetrate the entire outer sealing surface 1, and its inlet end 42 is connected to the medium side, and the outlet end 43 is connected to the ring groove 2.

[0043] The width of the ring groove 2 is 0.4 times the width of the outer sealing surface 1 (1 time means equal to the width of the outer sealing surface 1), and the width of the inner sealing surface 3 is 0.5 times the width of the outer sealing surface 1.

[0044] As Figure 3 、 Figure 4 shown, the drainage grooves 4 are evenly distributed in the circumferential direction, and the number thereof is 30.

[0045] The angle between the drainage groove 4 and the center line is 45°.

[0046] The wall 41 of the drainage groove is an arc surface.

[0047] The arc of the wall 41 of the drainage groove faces the medium side.

[0048] The wall 41 of the drainage groove is preferably perpendicular to the sealing end face.

[0049] The drainage groove 4 is set with equal depth, and its depth is 15 μm.

[0050] The drainage groove 4 is set with equal width, and its width is 0.15 mm.

[0051] The annular groove is close to 0.4 times, suitable for compact design or low-flow scenarios, reducing space occupation, while maintaining sufficient medium collection capacity. In a small sealing device, it can enhance the structural strength and avoid deformation under high-speed rotation.

[0052] The inner sealing surface is close to 0.5 times, suitable for low-load or low-speed scenarios, reducing the friction contact area and lowering energy consumption.

[0053] Refer to Figure 1 , in the sealed operating state, the pressurized fluid on the upstream side enters the radial drainage groove 4 and the end face gap under the shearing action of the seal dynamic ring end face. Under the action of the drainage groove 4 in the present invention, a strong hydrodynamic pressure effect is formed, thereby providing a highly stable pressure fluid film, making the seal have excellent load-bearing performance, small frictional power consumption and high stability, thus avoiding the phenomena of poor lubrication and dry friction wear on the inner side of the seal end face.

[0054] The annular groove is close to 1.2 times, suitable for working conditions of high flow or high-viscosity media, increasing the buffer area, reducing turbulence and pressure fluctuations, while reducing the medium flow resistance.

[0055] 1.5 times the inner sealing surface can maintain a large liquid film coverage area, ensure continuous lubrication and avoid dry friction.

[0056] Embodiment 2

[0057] The overall structure and implementation manner of this embodiment are the same as those of Embodiment 1.

[0058] The difference between this embodiment and Embodiment 1 lies in:

[0059] The width of the annular groove 2 is 1.2 times the width of the outer sealing surface 1 (1 time means equal width to the width of the outer sealing surface 1), and the width of the inner sealing surface 3 is 1.5 times the width of the outer sealing surface 1.

[0060] The drainage grooves 4 are evenly distributed in the circumferential direction, and the number thereof is 20.

[0061] The included angle between the drainage groove 4 and the center line is 60°.

[0062] The wall of the drainage groove adopts a plane, and the included angle between the wall of the drainage groove and the seal end face is 10°.

[0063] The drainage groove 4 is set with equal depth, and its depth is 60 μm.

[0064] The drainage groove 4 is of equal width, and its width is 0.20 mm.

[0065] A transition arc is provided at the connection between the outlet end 43 of the drainage groove 4 and the annular groove 2.

[0066] The inlet end 42 of the drainage groove 4 is provided with a chamfer structure, and the chamfering direction of the chamfer structure is consistent with the medium flow direction.

[0067] The annular groove is nearly 1.2 times, suitable for working conditions of high flow rate or high-viscosity media, which can increase the buffer area, reduce turbulence and pressure fluctuations, and at the same time reduce the medium flow resistance.

[0068] The inner sealing surface is nearly 1.5 times, which can maintain a large liquid film coverage area, ensure continuous lubrication, and avoid dry friction.

[0069] Compared with the arc-shaped groove wall, the flat groove wall is simpler to process. At the same time, the fluid flows along a straight path, with small flow resistance, and is suitable for low-viscosity media such as water and light oil.

[0070] The transition arc can smooth the connection between the drainage groove and the annular groove, reduce the sudden turning of the medium flow, reduce the local pressure loss, and improve the uniformity of the pressure distribution in the annular groove.

[0071] The chamfer structure can effectively reduce the turbulence and local resistance when the medium enters the drainage groove, prevent impurity jamming, and improve the medium introduction efficiency.

[0072] Embodiment 3

[0073] As Figure 1 shown, a mechanical seal end face and a mechanical seal with a drainage groove structure include a rotating ring and a stationary ring for mechanical end face sealing. It is characterized in that both the rotating ring and the stationary ring have a sealing end face, and the sealing end face of the sealing ring is sequentially provided with from outside to inside: an outer sealing surface 1, an annular groove 2, and an inner sealing surface 3;

[0074] As Figure 2 shown, the outer sealing surface 1 is provided with drainage grooves 4 distributed in the circumferential direction. The drainage grooves 4 penetrate the entire outer sealing surface 1, and its inlet end 42 is connected to the medium side, and the outlet end 43 is connected to the annular groove 2.

[0075] The width of the annular groove 2 is 0.4 times the width of the outer sealing surface 1 (1 time means equal width to the width of the outer sealing surface 1), and the width of the inner sealing surface 3 is 0.5 times the width of the outer sealing surface 1.

[0076] As Figure 3 、 Figure 5 shown, the drainage grooves 4 are evenly distributed in the circumferential direction, and the number thereof is 30.

[0077] The included angle between the drainage groove 4 and the center line is 45°.

[0078] The wall 41 of the drainage groove is an arc surface.

[0079] The arc of the wall 41 of the drainage groove faces the medium side.

[0080] The wall 41 of the drainage groove is preferably perpendicular to the sealing end face.

[0081] The drainage groove 4 is of equal depth, and its preferred depth value is 15 μm.

[0082] The drainage groove 4 is arranged to gradually widen from the inlet end to the outlet end. The width of the outlet end is 0.01 mm greater than that of the inlet end, and the width of the inlet end is 0.15 mm.

[0083] The gradually widening design reduces the flow rate of the medium, increases the residence time, and improves the pressure accumulation efficiency; at the same time, impurity particles can naturally slide into the annular groove as the channel widens, avoiding jamming and blockage.

[0084] Example 4

[0085] The overall structure and implementation manner of this example are the same as those of Example 3.

[0086] The difference between this example and Example 3 lies in:

[0087] The width of the annular groove 2 is 1.2 times the width of the outer sealing surface 1 (1 time means equal to the width of the outer sealing surface 1), and the width of the inner sealing surface 3 is 1.5 times the width of the outer sealing surface 1.

[0088] The drainage grooves 4 are evenly distributed in the circumferential direction, and the number thereof is 20.

[0089] The included angle between the drainage groove 4 and the center line is 60°.

[0090] The wall of the drainage groove is a plane, and the included angle between the wall of the drainage groove and the sealing end face is 10°.

[0091] The drainage groove 4 is of equal depth, and its preferred depth value is 60 μm.

[0092] The drainage groove 4 is arranged to gradually widen from the inlet end to the outlet end. The width of the outlet end is 0.1 mm greater than that of the inlet end, and the width of the inlet end is 0.20 mm.

[0093] A transition arc is provided at the connection between the outlet end 43 of the drainage groove 4 and the annular groove 2.

[0094] A chamfer structure is provided at the inlet end 42 of the drainage groove 4, and the chamfering direction of the chamfer structure is consistent with the medium flow direction.

[0095] The transition arc can smooth the connection between the drainage groove and the annular groove, reduce the sudden turning of the medium flow, lower the local pressure loss, and improve the uniformity of the pressure distribution in the annular groove.

[0096] The chamfer structure can effectively reduce the turbulence and local resistance when the medium enters the drainage groove, prevent impurity jamming, and improve the medium introduction efficiency.

[0097] Embodiment 5

[0098] As Figure 1 shown, a mechanical seal end face with a drainage groove structure and a mechanical seal include a rotating ring and a stationary ring for mechanical end face sealing. It is characterized in that both the rotating ring and the stationary ring have a sealing end face, and the sealing end face of the sealing ring is successively provided with from outside to inside: an outer sealing surface 1, an annular groove 2, and an inner sealing surface 3;

[0099] As Figure 2 shown, the outer sealing surface 1 is provided with drainage grooves 4 distributed along the circumferential direction. The drainage grooves 4 penetrate the entire outer sealing surface 1, and its inlet end 42 is connected to the medium side, and the outlet end 43 is connected to the annular groove 2.

[0100] The width of the annular groove 2 is 0.4 times the width of the outer sealing surface 1 (1 time means equal width to the width of the outer sealing surface 1), and the width of the inner sealing surface 3 is 0.5 times the width of the outer sealing surface 1.

[0101] As Figure 3 、 Figure 6 The drainage grooves 4 are evenly distributed in the circumferential direction, and the number thereof is 30.

[0102] The included angle between the drainage groove 4 and the center line is 45°.

[0103] The groove wall 41 of the drainage groove is an arc surface.

[0104] The arc of the groove wall 41 of the drainage groove faces the medium side.

[0105] Preferably, the groove wall 41 of the drainage groove is perpendicular to the sealing end face.

[0106] The drainage groove 4 is arranged to gradually become deeper from the inlet end to the outlet end. The depth of the outlet end is 0.01 μm greater than the depth of the inlet end, and the depth of the inlet end is 15 μm.

[0107] The drainage groove 4 is arranged with an equal width, and its width is 0.15 mm.

[0108] The gradually deepening setting can enhance the compression effect of the fluid through the depth gradient, significantly increase the medium pressure in the annular groove; the increase in the inner end depth can accelerate the flow of the medium towards the inner sealing surface and prevent the liquid film from breaking.

[0109] Example 6

[0110] The overall structure and implementation method of this example are the same as those of Example 5.

[0111] The difference between this example and Example 5 lies in:

[0112] The width of the ring groove 2 is 1.2 times the width of the outer sealing surface 1 (1 time means equal width to the width of the outer sealing surface 1), and the width of the inner sealing surface 3 is 1.5 times the width of the outer sealing surface 1.

[0113] The drainage grooves 4 are evenly distributed in the circumferential direction, and the number thereof is 20.

[0114] The included angle between the drainage groove 4 and the center line is 60°.

[0115] The wall of the drainage groove is a plane, and the included angle between the wall of the drainage groove and the sealing end face is 10°.

[0116] The drainage groove 4 is arranged to gradually become deeper from the inlet end to the outlet end. The depth of the outlet end is 10 μm greater than that of the inlet end, and the depth of the inlet end is 60 μm.

[0117] The drainage groove 4 is arranged with equal width, and its width is 0.20 mm.

[0118] A transition arc is provided at the connection between the outlet end 43 of the drainage groove 4 and the ring groove 2.

[0119] A chamfer structure is provided at the inlet end 42 of the drainage groove 4, and the chamfer direction of the chamfer structure is consistent with the medium flow direction.

[0120] The transition arc can smooth the connection between the drainage groove and the ring groove, reduce the sudden turning of the medium flow, reduce the local pressure loss, and improve the uniformity of the pressure distribution in the ring groove.

[0121] The chamfer structure can effectively reduce the turbulence and local resistance when the medium enters the drainage groove, prevent impurity jamming, and improve the medium introduction efficiency.

[0122] Example 7

[0123] As Figure 1 shown, a mechanical seal end face and a mechanical seal with a drainage groove structure include a rotating ring and a stationary ring for mechanical end face sealing. The feature is that both the rotating ring and the stationary ring have sealing end faces, and the sealing end faces of the sealing rings are successively provided with from outside to inside: an outer sealing surface 1, a ring groove 2, and an inner sealing surface 3;

[0124] As Figure 2As shown, a drainage groove 4 is provided on the outer sealing surface 1 and is distributed along the circumferential direction. The drainage groove 4 penetrates the entire outer sealing surface 1. Its inlet end 42 is connected to the medium side, and its outlet end 43 is connected to the ring groove 2.

[0125] The width of the ring groove 2 is 0.4 times the width of the outer sealing surface 1 (1 time means equal to the width of the outer sealing surface 1), and the width of the inner sealing surface 3 is 0.5 times the width of the outer sealing surface 1.

[0126] As Figure 3 、 Figure 7 shown, the drainage grooves 4 are evenly distributed in the circumferential direction, and the number thereof is 30.

[0127] The included angle between the drainage groove 4 and the center line is 45°.

[0128] The wall 41 of the drainage groove is an arc surface.

[0129] The arc of the wall 41 of the drainage groove faces the medium side.

[0130] The wall 41 of the drainage groove is preferably perpendicular to the sealing end face.

[0131] The drainage groove 4 is arranged to gradually become deeper from the inlet end to the outlet end. The depth of the outlet end is 0.01 μm greater than the depth of the inlet end, and the depth of the inlet end is 15 μm.

[0132] The drainage groove 4 is arranged to gradually become wider from the inlet end to the outlet end. The width of the outlet end is 0.01 mm greater than the width of the inlet end, and the width of the inlet end is 0.15 mm.

[0133] Example 8

[0134] The overall structure and implementation manner of this example are the same as those of Example 7.

[0135] The width of the ring groove 2 is 1.2 times the width of the outer sealing surface 1 (1 time means equal to the width of the outer sealing surface 1), and the width of the inner sealing surface 3 is 1.5 times the width of the outer sealing surface 1.

[0136] The difference between this example and Example 7 lies in:

[0137] The drainage grooves 4 are evenly distributed in the circumferential direction, and the number thereof is 20.

[0138] The included angle between the drainage groove 4 and the center line is 60°.

[0139] The wall of the drainage groove adopts a plane, and the included angle between the wall of the drainage groove and the sealing end face is 10°.

[0140] The drainage groove 4 is arranged such that its depth gradually increases from the inlet end to the outlet end. The depth of the outlet end is 10 μm greater than that of the inlet end, and the depth of the inlet end is 60 μm.

[0141] The drainage groove 4 is arranged such that its width gradually increases from the inlet end to the outlet end. The width of the outlet end is 0.1 mm greater than that of the inlet end, and the width of the inlet end is 0.20 mm.

[0142] A transition arc is provided at the connection between the outlet end 43 of the drainage groove 4 and the annular groove 2.

[0143] A chamfer structure is provided at the inlet end 42 of the drainage groove 4, and the chamfer direction of the chamfer structure is consistent with the medium flow direction.

[0144] The transition arc can smooth the connection between the drainage groove and the annular groove, reduce the sudden turning of the medium flow, lower the local pressure loss, and improve the uniformity of the pressure distribution in the annular groove.

[0145] The chamfer structure can effectively reduce the turbulence and local resistance when the medium enters the drainage groove, prevent impurity jamming, and improve the medium introduction efficiency.

[0146] Due to the progressive setting of the drainage groove 4, when small particle impurities enter the drainage groove, the impurities will not get stuck in the drainage groove 4 and can smoothly enter the annular groove 2, effectively preventing the impurities from entering the outer sealing end face through the notch position at the inlet end of the drainage groove 4.

[0147] So far, the embodiments of the present invention have been described in detail. To avoid obscuring the concept of the present invention, some details well known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0148] Although some specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present invention. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be equivalently replaced without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A mechanical seal end face with a drainage groove structure, the mechanical seal comprises a rotating ring and a stationary ring, the rotating ring and the stationary ring together constitute a friction pair, characterized in that: The rotating ring and the stationary ring both have coaxially arranged annular sealing end faces, and the sealing end faces are based on the center of the sealing ring and are arranged in sequence along the radial direction from the outer edge to the center of the circle: an outer sealing surface (1), an annular groove (2), and an inner sealing surface (3); The outer sealing surface (1) is provided with drainage grooves (4) distributed along the circumferential direction, the drainage grooves (4) penetrate the entire outer sealing surface (1), the inlet end (42) is connected to the medium side, and the outlet end (43) is connected to the annular groove (2); The drainage groove (4) has a depth of 15 μm to 60 μm and a width of 0.15 mm to 0.20 mm; The width of the annular groove (2) is 0.4 to 1.2 times the width of the outer sealing surface (1), and the width of the inner sealing surface (3) is 0.5 to 1.5 times the width of the outer sealing surface (1).

2. The mechanical seal end face with a drainage groove structure according to claim 1, characterized in that: The drainage grooves (4) are evenly distributed in the circumferential direction, and the number thereof is 20 to 30.

3. The mechanical seal end face with a drainage groove structure according to claim 1, characterized in that: The drainage groove (4) has a certain angle α with the center line, and the angle is between 45° and 60°.

4. The mechanical seal end face with a drainage groove structure according to claim 1, characterized in that: The drainage groove wall (41) is a plane or an arc surface; when the drainage groove wall (41) is an arc surface, the arc of the drainage groove wall (41) faces the medium side.

5. The mechanical seal end face with a drainage groove structure according to claim 1, characterized in that: The drainage groove wall (41) is perpendicular to the sealing end surface, or has an angle with the sealing end surface within 10°.

6. The mechanical seal end face with a drainage groove structure according to claim 1, characterized in that: The drainage grooves (4) are arranged with equal depth, with a depth of 15 μm to 60 μm; or, the drainage grooves (4) are arranged with a depth gradually increasing from the inlet end (42) to the outlet end (43), with a depth of 15 μm to 50 μm at the inlet end (42) and a depth of 20 μm to 60 μm at the outlet end (43), and the depth of the inlet end (42) is 5 μm to 10 μm greater than that of the outlet end (43).

7. The mechanical seal end face with a drainage groove structure according to claim 1, characterized in that: The drainage grooves (4) are arranged with equal width, and the width is 0.15 mm to 0.20 mm; or, the width of the drainage grooves (4) gradually increases from the inlet end (42) to the outlet end (43), the width of the inlet end (42) is 0.15 mm to 0.20 mm, the width of the outlet end (43) is 0.20 mm to 0.25 mm, and the width of the inlet end (42) is 0.05 mm to 0.10 mm greater than that of the outlet end (43).

8. The mechanical seal end face with a drainage groove structure according to claim 1, characterized in that: A transition arc is provided at the connection between the outlet end (43) of the drainage groove (4) and the annular groove (2).

9. The mechanical seal end face with a drainage groove structure according to claim 1, characterized in that: The inlet end (42) of the drainage groove (4) is provided with a chamfered structure, and the chamfering direction of the chamfered structure is consistent with the flow direction of the medium.

10. A mechanical seal, characterized in that: The mechanical seal adopts the mechanical seal end face structure with a drainage groove structure as described in any one of claims 1-9.

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