CN114857272B - End face seal assembly - Google Patents

Abstract

The invention discloses an end face seal assembly, which comprises: a first seal ring formed with a first end face; a second seal ring which is provided with a second end face opposite to the first end face, and a seal gap extending from a high pressure side to a low pressure side is formed between the first end face and the second end face; the first end face and at least one of the second end face are provided with circumferential grooves, at least one of the first end face and the second end face is provided with radial grooves, the circumferential grooves and the radial grooves are located between a high pressure side and a low pressure side to control the phase change position of fluid in the sealing gap, and the radial grooves are arranged on the low pressure side of the circumferential grooves. The end face sealing assembly can effectively control the potential position of phase change, so that the phase change occurs in a smaller area, and meanwhile, the actual end face specific pressure of the seal is improved, and the bearing capacity of the seal is improved.

Description

End face seal assembly

Technical Field

The invention relates to the technical field of mechanical sealing, in particular to an end face sealing assembly.

Background

Mechanical seal face structures are a fundamental key component in various rotary fluid machines. The mechanical seal is a device with less fluid leakage, which keeps the sealing rings to be jointed and relatively slide under the combined action of the end face fluid pressure vertical to the rotation axis, the action of the compensation element and the auxiliary seal. The common mechanical end face seal has relatively mature sealing end face and structural design for sealing a gas medium and a liquid medium. With the development of sealing technology and the extension of sealing application media, there are also deficiencies and gaps in the related designs for media applications where phase changes may occur on both sides of the seal due to pressure and temperature differences. Basically, the application scenario is that the medium is kept in a liquid state under a certain temperature and pressure in the sealed cavity, and is changed into a vapor phase under the condition outside the seal. Therefore, the phase change usually occurs on the sealing end surface, and if the phase change is not controlled by adopting a targeted design, the sealing cannot work effectively, and even a failure or accident occurs. For this case, it is more common to have a contact mechanical end face seal, the end face of which is not provided with any groove-type, substantially flat end face. The design has the defects of larger abrasion of the sealing end face and relatively shorter service life, so that the non-contact end face seal adopting taper and partial deep grooves is designed, and the purpose is to improve the opening force by utilizing the hydrostatic pressure effect, thereby improving the friction and abrasion condition. But such hydrostatic seals have fewer controllable design parameters and tend to have higher leak rates. Still other end face designs utilize hydrodynamic effects, often based on the direction of rotation of the end face, to provide dynamic pressure shallow grooves, such as spiral shallow grooves with depths of several micrometers to tens of micrometers, which can combine the advantages of friction and wear improvement and leakage rate control. However, the dynamic pressure grooves have directionality, and the advantages of the dynamic pressure grooves fail even at low speed under the condition of unstable rotation direction, and the processing cost of the shallow grooves is relatively high. The present application is directed to an end face seal assembly that addresses the above-described issues.

Disclosure of Invention

The present invention aims to solve at least one of the technical problems existing in the prior art. Therefore, an object of the present invention is to provide an end face seal assembly that improves the pressure distribution in the seal gap, so that the partial pressure on the seal end face is maintained above the fluid saturated vapor pressure in a radially wider range, limits the potential location where phase changes occur, allows phase changes to occur in a smaller area, reduces the end face specific pressure of the seal, improves the seal bearing capacity, protects the end face during low speed operation and start-stop phases, and reduces unnecessary wear.

An end face seal assembly according to an embodiment of the present invention includes: a first seal ring formed with a first end face; a second seal ring which is provided with a second end face opposite to the first end face, and a seal gap extending from a high pressure side to a low pressure side is formed between the first end face and the second end face; the first end face and at least one of the second end face are provided with circumferential grooves, at least one of the first end face and the second end face is provided with radial grooves, the circumferential grooves and the radial grooves are located between a high pressure side and a low pressure side to control the phase change position of fluid in the sealing gap, and the radial grooves are arranged on the low pressure side of the circumferential grooves.

According to the end face sealing assembly, the radial grooves are arranged on the low-pressure side of the circumferential grooves, along with the radial inflow of fluid outside the sealing end face into the sealing gap, the pressure in the sealing gap also decreases along the radial direction, and the pressure in the sealing gap stops decreasing after the fluid flows into the circumferential deep grooves, and the pressure of the fluid in a certain width is stable due to the arrangement of a series of radial grooves. The manner in which the pressure drop is limited is such that the radial pressure remains above the fluid saturation vapor pressure over a wider range, thereby controlling the potential location where the phase change occurs, allowing the phase change to occur in a smaller area. The limitation of pressure reduction simultaneously reduces the actual end face specific pressure of the seal, thereby improving the bearing capacity of the seal, leading the low-speed operation and start-stop stage of the seal to have better performance, protecting the end face and reducing unnecessary abrasion.

According to some embodiments of the invention, the circumferential groove is configured in a plurality, a plurality of the circumferential grooves encircling the first seal ring center of rotation, any one of the radial grooves being located on a low pressure side of the circumferential groove adjacent to a high pressure side.

According to some embodiments of the invention, the radial slots are arranged between two adjacent circumferential slots and/or on the low pressure side of the circumferential slots adjacent to the low pressure side.

According to some embodiments of the invention, the radial slots are configured in a plurality of groups sequentially arranged in a radial direction, each group of the radial slots having a plurality of circumferentially spaced apart groups, the circumferential slots being sequentially arranged in a radial direction with the radial slots.

According to some embodiments of the invention, adjacent two sets of the radial grooves are staggered in the circumferential direction.

According to some embodiments of the invention, at least one set of the circumferential grooves is configured as a wave that continuously bulges in the circumferential direction towards the high pressure side or the low pressure side.

According to some embodiments of the invention, the circumferential groove comprises: a high-pressure side circumferential groove configured in a wavy shape that continuously protrudes in a circumferential direction toward the high-pressure side, and a low-pressure side circumferential groove configured in a wavy shape that continuously protrudes in a circumferential direction toward the low-pressure side.

According to some embodiments of the invention, the high pressure side circumferential groove has a plurality of first wave trough portions adjacent to the low pressure side, the low pressure side circumferential groove has a plurality of second wave trough portions adjacent to the high pressure side, the first wave trough portions and the second wave trough portions are arranged corresponding to each other in a radial direction, and a radial groove is arranged between each of the first wave trough portions and the second wave trough portions.

According to some embodiments of the invention, the radial groove is provided at the first end face and/or the second end face.

According to some embodiments of the invention, the circumferential groove has a depth d1, the radial groove has a depth d2, and: d1 is more than or equal to 0.05mm and less than or equal to 2mm, d2 is more than or equal to 0.05mm and less than or equal to 2mm.

According to some embodiments of the invention, the circumferential groove has a width D1, the radial groove has a width D2, and: d1 is more than or equal to 0.1mm and less than or equal to 2mm, D2 is more than or equal to 0.1mm and less than or equal to 2mm.

According to some embodiments of the invention, the circumferential groove is configured as a plurality of wave segments, fold segments or curves that are circumferentially continuous.

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.

Drawings

The foregoing and/or additional aspects and advantages of the invention will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic illustration of the configuration of an end face seal assembly according to one embodiment of the present invention;

FIG. 2 is a schematic illustration of an end face seal assembly according to another embodiment of the present invention;

FIG. 3 is a schematic illustration of an end face seal assembly according to another embodiment of the present invention;

FIG. 4 is a schematic illustration of the configuration of an end face seal assembly according to another embodiment of the present invention;

FIG. 5 is a schematic plan view of a circumferential groove and a radial groove of one embodiment of the present invention;

FIG. 6 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 7 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 8 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 9 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 10 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 11 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 12 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 13 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 14 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 15 is a schematic plan view of a circumferential groove and a radial groove of another embodiment of the present invention;

FIG. 16 is a pressure profile of an end face seal assembly according to one embodiment of the present invention;

FIG. 17 is a schematic diagram of the phase distribution of an end face seal assembly according to one embodiment of the present invention.

Reference numerals:

1: a shaft; 2: a housing; 3: a first seal ring; 4: a second seal ring; 5: a first radial slot; 6: a high pressure side circumferential groove; 7: sealing the dam; 8: a second radial slot; 9: a low pressure side circumferential groove; 10: a first circumferential groove; 11: a first trough portion; 12: the second trough portion.

Detailed Description

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; may be mechanically connected, may be electrically connected or may communicate with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

In the related art, a mechanical seal end face structure is a fundamental key component in various rotary fluid machines. For medium application which can generate phase change on two sides of the seal due to different pressure and temperature, a contact type mechanical end face seal is more common, the end face of the mechanical end face seal is mostly not provided with any groove type and is basically a flat end face, the end face of the seal is more worn and has a relatively short service life, so that non-contact end face seals adopting taper and local deep grooves are designed, and the purpose is to improve opening force by utilizing the hydrostatic pressure effect, and further improve friction and wear conditions. But such hydrostatic seals have fewer controllable design parameters and tend to have higher leak rates. Still other end face designs utilize hydrodynamic effects, often based on the direction of rotation of the end face, to provide dynamic pressure shallow grooves, such as spiral shallow grooves with depths of several micrometers to tens of micrometers, which can combine the advantages of friction and wear improvement and leakage rate control. However, the dynamic pressure grooves have directionality, and the advantages of the dynamic pressure grooves fail even at low speed under the condition of unstable rotation direction, and the processing cost of the shallow grooves is relatively high. The present application is directed to designing an end face seal assembly to address the above-described technical problems to a certain extent.

An end face seal assembly according to an embodiment of the present invention is described below with reference to fig. 1-17.

The end face sealing assembly comprises a first sealing ring 3 and a second sealing ring 4, wherein the first sealing ring 3 is provided with a first end face, the second sealing ring 4 is provided with a second end face opposite to the first end face, a sealing gap extending from a high pressure side to a low pressure side is formed between the first end face and the second end face, fluid can flow into the sealing gap to form a fluid film, at least one of the first end face and the second end face is provided with a circumferential groove, at least one of the first end face and the second end face is provided with a radial groove, the circumferential groove and the radial groove are both positioned between the high pressure side and the low pressure side to control the phase change position of the fluid in the sealing gap, and the radial groove is arranged on the low pressure side of the circumferential groove.

The radial groove provided on the low pressure side of the circumferential groove means that when the fluid flows into the seal gap from the outside of the seal end surface, the fluid flows into the circumferential groove and then into the radial groove. Referring to fig. 5, when the end face seal assembly includes only one circumferential groove and one radial groove, when fluid flows into the seal gap from the outside of the seal end face, the fluid flows into the circumferential groove, then flows into the radial groove, and finally flows to the seal dam 7 between R0 and R4 and between R1 and R3; when the end face sealing assembly comprises a plurality of circumferential grooves or a plurality of radial grooves or a plurality of circumferential grooves and radial grooves, when fluid flows into the sealing gap from the outer side of the sealing end face, the fluid flows into the circumferential grooves, then flows into the radial grooves and then flows into other groove bodies at the low pressure side of the radial grooves. R0 is an inner radius of a seal end face between the first seal ring and the second seal ring, R1 is an outer radius of a seal end face between the first seal ring and the second seal ring, R2 is an inner radius of the high-pressure side circumferential groove 6, and R3 is an outer radius of the high-pressure side circumferential groove 6.

It is known to those skilled in the art that for a fluid flowing within a seal gap there will be a decrease in along-line pressure in the direction of flow, the extent of the pressure decrease being inversely proportional to the dimension of the seal gap, the greater the dimension of the seal gap, the lesser the extent of the pressure decrease. According to the end face sealing assembly provided by the invention, the circumferential groove is formed on at least one of the first end face and the second end face, the radial groove is arranged on the low pressure side of the circumferential groove, and referring to fig. 16, as fluid outside the sealing end face flows into the sealing gap along the radial direction, the pressure in the sealing gap also decreases along the radial direction and stops decreasing after flowing into the circumferential deep groove, and the pressure of the fluid is stable within a certain width due to the arrangement of a series of radial grooves. The manner in which the pressure drop is limited is such that the radial pressure remains above the fluid saturation vapor pressure over a wider range, see fig. 17, thereby controlling the potential location where the phase change occurs, allowing the phase change to occur in a smaller area. It should be noted that if a phase change occurs in the seal gap, the area ratio occupied by the vapor phase will be relatively large, and since the viscosity of the gas is far less than that of the liquid, the large-area vaporization area is unfavorable for maintaining the working state of the seal, and by restricting the phase change to a limited area, the lubrication area is correspondingly enlarged, so that the abrasion between the first end face and the second end face due to contact is effectively reduced, and the working life of the end face seal assembly is remarkably prolonged. The limitation of pressure reduction simultaneously reduces the actual end face specific pressure of the seal, thereby improving the bearing capacity of the seal, leading the low-speed operation and start-stop stage of the seal to have better performance, protecting the end face and reducing unnecessary abrasion.

According to some embodiments of the present invention, when the end face seal assembly is used for a rotary machine seal, the rotary machine further comprises a shaft 1 and a housing 2, the bottom of the housing 2 is perforated, the shaft 1 of the rotary machine passes through the hole, the housing 2 is fixedly connected with a first seal ring 3, the first seal ring 3 is formed with a first end face, a second seal ring 4 is connected with the shaft 1 and can rotate around the shaft 1, the second seal ring 4 is formed with a second end face, and the first end face of the first seal ring 3 is in face fit with the second end face of the second seal ring 4. It should be noted that, the operation states of the first seal ring 3 and the second seal ring 4 are not particularly limited, and the second seal ring may be fixedly connected to the housing 2, the first seal ring 3 rotates around the shaft 1, a high pressure area is formed outside the first seal ring 3 and the second seal ring 4 in the housing 2, a low pressure area is formed between the shaft body and the first seal ring 3 and the second seal ring 4, and a medium in the high pressure area in the housing 2 may enter the low pressure area through a seal gap so as to lubricate and improve the bearing capacity between the first seal ring 3 and the second seal ring 4 when the first seal ring 3 and the second seal ring 4 rotate relatively.

According to some embodiments of the present invention, the positions of the radial groove and the circumferential groove on the seal ring are not particularly limited, for example, referring to fig. 1, the first radial groove 5 and the high pressure side circumferential groove 6 may each be provided on the second seal ring 4; referring to fig. 2, a first radial groove 5 and a high pressure side circumferential groove 6 may each be provided on the first seal ring 3; referring to fig. 3, a first radial groove 5 is provided on the second seal ring 4, and a high-pressure side circumferential groove 6 is provided on the first seal ring 3; referring to fig. 4, a first radial groove 5 is provided on the first seal ring 3, and a high pressure side circumferential groove 6 is provided on the second seal ring 4, which can be selected according to actual needs by those skilled in the art.

According to some embodiments of the invention, the circumferential groove may be a continuous groove or a discontinuous groove, and referring to fig. 6, the circumferential groove includes a plurality of connection segments arranged at intervals in the circumferential direction, each connection segment being in communication with one or more radial grooves located on the low pressure side. Specifically, the circumferential groove on the seal ring may be formed of a plurality of connecting segments disconnected from each other, each of the connecting segments being a segment of groove, and one end of the radial groove may communicate with the low pressure side of each of the connecting segments of the circumferential groove to form circumferentially arranged T-shaped grooves.

According to some embodiments of the invention, the circumferential groove may be configured in a plurality, the plurality surrounding the first seal ring center of rotation, any one of the radial grooves being located on the low pressure side of the circumferential groove adjacent the high pressure side. For example, referring to FIG. 8, two circumferential grooves are configured on the face seal assembly, and referring to FIG. 12, three circumferential grooves are configured on the face seal assembly. It should be noted that, the fluid flows into the sealing gap from the outside of the sealing end surface, there is a pressure loss along the way, the pressure is in a decreasing trend in the whole flowing process, the fluid pressure stops decreasing after flowing into the circumferential groove, and the fluid pressure is stabilized in a certain range due to the arrangement of a series of radial grooves, namely, the pressures at two sides of the circumferential groove are different, the upstream direction of the fluid is the high pressure side of the circumferential groove, the downstream direction of the fluid is the low pressure side of the circumferential groove, and one or more groups of radial grooves are all positioned at the low pressure side of the circumferential groove into which the fluid flows first. When the fluid flows on the sealing end face, the plurality of circumferential grooves are arranged on the sealing end face, so that the area of the fluid with the pressure above the saturated vapor pressure of the fluid is enlarged, namely, the high-pressure area in the sealing gap is enlarged, the potential position of phase change is further controlled, and the area of the phase change is reduced.

According to some embodiments of the invention, the radial slots may be arranged between two adjacent circumferential slots and/or at the low pressure side of a circumferential slot adjacent to the low pressure side. Specifically, referring to fig. 11, the first radial groove 5 is provided between the high-pressure side circumferential groove 6 and the low-pressure side circumferential groove 9, or the radial groove is provided on the low-pressure side (not shown in the figure) of the low-pressure side circumferential groove, or, referring to fig. 8, the first radial groove 5 is provided between the high-pressure side circumferential groove 6 and the low-pressure side circumferential groove 9, and the second radial groove 6 is provided on the low-pressure side of the low-pressure side circumferential groove 9. Therefore, the radial grooves can keep the pressure of fluid flowing out of the circumferential grooves within a certain width range, even if the fluid is kept above saturated vapor pressure, the potential position of phase change occurrence is controlled, the area of the phase change occurrence is reduced, the sealing effect is improved, the plurality of groups of radial grooves can further reduce the area of the phase change occurrence, the area of the fluid in a liquid state is increased, the lubrication area is increased, the end face specific pressure is effectively reduced, abrasion caused by contact between the first end face and the second end face is reduced, and the service life of the end face sealing assembly is remarkably prolonged.

According to some embodiments of the invention, referring to fig. 12, the radial slots are configured in a plurality of groups sequentially arranged in the radial direction, each group of radial slots having a plurality of circumferentially spaced apart, circumferential slots being sequentially arranged in the radial direction with the radial slots. Specifically, the radial grooves and the circumferential grooves are arranged in this order in the radial direction, that is, after the fluid flows into the seal gap from the outside of the seal end face, the fluid flows into the high-pressure side circumferential groove 6, the first radial groove 5, the first circumferential groove 10, the second radial groove 8, the low-pressure side circumferential groove 9, and the like in this order.

Therefore, the potential area where phase change occurs can be further reduced by the plurality of groups of radial grooves and the plurality of groups of circumferential grooves, the area of the area where fluid is in a liquid state is increased, the lubrication area is increased, abrasion between the first end face and the second end face due to contact is effectively reduced, and the service life of the end face sealing assembly is remarkably prolonged.

According to some embodiments of the invention, referring to fig. 8, two adjacent sets of radial grooves are staggered in circumferential direction, i.e. a first radial groove 5 faces the gap formed by two adjacent second radial grooves 8, the second radial grooves 8 also face the gap formed by two adjacent first radial grooves 5. Specifically, the first radial groove 5 is disposed between two adjacent circumferential grooves, the second radial groove 8 is disposed on the low pressure side of the low pressure side circumferential groove 9, and a sealing dam 7 is formed between R0 and R4 and between R1 and R3 to play a role in throttling and stopping sealing.

According to some embodiments of the present invention, at least one set of circumferential grooves is configured in a wavy shape that continuously protrudes in the circumferential direction toward the high pressure side or the low pressure side, and in particular, referring to fig. 7, the end face seal assembly is provided with only one circumferential groove, which may be regarded as the high pressure side circumferential groove 6, the high pressure side circumferential groove 6 may be configured in a wavy shape that continuously protrudes in the circumferential direction toward the high pressure side, or the high pressure side circumferential groove 6 may be configured in a wavy shape (not shown in the figure) that continuously protrudes in the circumferential direction toward the low pressure side; according to other embodiments of the present invention, referring to fig. 9, the end face seal assembly is provided with two circumferential grooves, one being a high-pressure side circumferential groove 6 and the other being a low-pressure side circumferential groove 9, both of which are configured in a wavy shape that continuously protrudes toward the high-pressure side in the circumferential direction; according to other embodiments of the present invention, referring to fig. 10, two circumferential grooves are provided on the end face seal assembly, one being a high-pressure side circumferential groove 6 and the other being a low-pressure side circumferential groove 9, the high-pressure side circumferential groove 6 being configured in a wavy shape that continuously protrudes in the circumferential direction toward the high-pressure side, or the low-pressure side circumferential groove 9 being configured in a wavy shape (not shown in the figure) that continuously protrudes in the circumferential direction toward the high-pressure side; according to other embodiments of the present invention, referring to fig. 14, three circumferential grooves, namely, a high-pressure side circumferential groove 6, a low-pressure side circumferential groove 9, and a first circumferential groove 10, are provided on the end face seal assembly, and the high-pressure side circumferential groove 6 is configured in a wavy shape that continuously protrudes toward the high-pressure side in the circumferential direction.

According to some embodiments of the present invention, the protruding directions of the plurality of wavy circumferential grooves waves may be non-uniform, and referring to fig. 13, the circumferential grooves include a high-pressure side circumferential groove 6 and a low-pressure side circumferential groove 9, the high-pressure side circumferential groove 6 may be configured as a wavy shape protruding continuously in the circumferential direction toward the high-pressure side, and the low-pressure side circumferential groove 9 may be configured as a wavy shape protruding continuously in the circumferential direction toward the low-pressure side. The high pressure side and the low pressure side referred to herein are opposite, the pressure gradually decreases in the fluid flow direction as a whole, the high pressure side circumferential groove 6 means that the circumferential groove is provided upstream in the fluid flow direction, the low pressure side circumferential groove 9 means that the circumferential groove is provided downstream in the fluid flow direction, and the high pressure side circumferential groove 6 is configured in a wavy shape protruding toward the high pressure side.

According to some embodiments of the present invention, referring to fig. 13, the high pressure side circumferential groove 6 has a plurality of first wave trough portions 11 adjacent to the low pressure side, the low pressure side circumferential groove 9 has a plurality of second wave trough portions 12 adjacent to the high pressure side, the first wave trough portions 11 and the second wave trough portions 12 are disposed corresponding to each other in a radial direction, and a radial groove is disposed between each of the first wave trough portions 11 and the second wave trough portions 12. Specifically, the high-pressure side circumferential groove 6 may be configured in a wavy shape that continuously protrudes toward the high-pressure side in the circumferential direction, both ends of each wave of the high-pressure side circumferential groove 6 are first wave trough portions 11, the low-pressure side circumferential groove 9 may be configured in a wavy shape that continuously protrudes toward the low-pressure side in the circumferential direction, both ends of each wave of the low-pressure side circumferential groove 9 are second wave trough portions 12, when the first wave trough portions 11 and the second wave trough portions 12 are correspondingly disposed in the radial direction, the first wave trough portions 11 and the second wave trough portions 12 may be communicated through the first radial grooves 4, the communicated high-pressure side circumferential groove 6, the low-pressure side circumferential groove 9 and the first radial grooves 5 may form a circular groove body, and the continuous waves may form a plurality of circular rings that are communicated with each other.

According to some embodiments of the present invention, the radial groove may be disposed on the first end face and/or the second end face, specifically, the radial groove may be disposed on the first end face only, or the radial groove may be disposed on the second end face only, or both the first end face and the second end face are provided with radial grooves, where it is noted that the radial grooves disposed on the first end face and the second end face may be communicated or not communicated, and those skilled in the art may design according to actual needs.

According to some embodiments of the invention, referring to fig. 3, the depth d1 of the circumferential groove may be constant or may be varied. Alternatively, the circumferential groove may be the same depth in the entire circumferential direction, in which case the depth d1 of the circumferential groove is constant; the depth of the circumferential groove in the circumferential direction may also vary periodically, e.g. every 60 degrees, the circumferential groove having a variation of waviness, the depth d1 of the circumferential groove satisfying 0.05 mm.ltoreq.d1.ltoreq.2mm according to some embodiments of the present invention. Therefore, compared with the shallow grooves, the circumferential grooves adopt deep grooves, the deep grooves are more in processing modes, more in processing modes and more in available processing modes, the requirements of the deep grooves on precision are relatively tolerant, and the production cost can be reduced to a certain extent.

According to some embodiments of the invention, referring to fig. 4, the depth d2 of the radial groove may be constant or may be varied. Alternatively, the bottom surface of the radial groove may be planar, in which case the depth d2 of the radial groove is constant; the bottom surface of the radial groove may also be beveled, where the depth of the radial groove varies, and according to some embodiments of the invention, the depth d2 of the radial groove satisfies 0.05mm 2. Therefore, the radial grooves adopt deep grooves, compared with the shallow grooves, the deep grooves are processed in a relatively large number of ways, the applicable process means are relatively large in number, the requirements of the deep grooves on the precision are relatively tolerant, and the production cost can be reduced to a certain extent.

According to some embodiments of the invention, referring to fig. 8, the width D1 of the circumferential groove may be constant or may be varied. Alternatively, the width of the circumferential groove is uniform over the entire circumference, or the bottom to the notch of the circumferential groove is of a closed type or an open type, in which case the width of the circumferential groove in the radial direction is varied, and according to some embodiments of the present invention, the width D1 of the circumferential groove satisfies 0.1 mm.ltoreq.D1.ltoreq.2 mm.

According to some embodiments of the invention, referring to fig. 8, the width D2 of the radial slot may be constant or may be varied. Alternatively, the width of the bottom of the radial groove to the width of the notch may be uniform, or the bottom of the radial groove to the notch may be of a closed type or an open type, in which case the width of the radial groove varies, and the width D2 of the radial groove satisfies 0.1 mm.ltoreq.D1.ltoreq.2 mm according to some embodiments of the present invention.

According to some embodiments of the present invention, the shape and configuration of the circumferential groove are not particularly limited, and may be a plurality of wave segments, fold segments or curves that are continuous in the circumferential direction to accommodate different conditions. As shown in fig. 9, the first circumferential groove may be configured in a wavy shape, and the second circumferential groove may be configured in a wavy shape, and depending on the sizes of the first seal ring 3 and the second seal ring 4, and the kinds of different mediums and the distribution of the high pressure side and the low pressure side, wavy circumferential grooves protruding toward the radially outer portion may be provided, or wavy circumferential grooves protruding toward the inner portion may be provided. The circumferential groove is in a wavy shape, so that the range of fluid pressure maintained by the circumferential groove is larger, the circumferential groove has the effect achieved by a certain radial groove, and the range of fluid pressure change controlled by the circumferential groove is enlarged. In the machining process, the efficiency of machining the wavy circumferential groove is high compared with the machining of the annular circumferential groove and the radial groove at the same time.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the invention, the scope of which is defined by the claims and their equivalents.

Claims (10)

1. An end face seal assembly, comprising:

a first seal ring formed with a first end face;

a second seal ring which is provided with a second end face opposite to the first end face, and a seal gap extending from a high pressure side to a low pressure side is formed between the first end face and the second end face; wherein the method comprises the steps of

A circumferential groove is formed on at least one of the first end face and the second end face, a radial groove is formed on at least one of the first end face and the second end face, the circumferential groove and the radial groove are both positioned between a high pressure side and a low pressure side so as to control the position of fluid phase change in the sealing gap, and the radial groove is arranged on the low pressure side of the circumferential groove;

the plurality of circumferential grooves are configured, the plurality of circumferential grooves encircle the rotation center of the first sealing ring, and any one of the radial grooves is positioned on the low pressure side of the circumferential groove adjacent to the high pressure side;

the circumferential groove includes: a high-pressure side circumferential groove configured in a wavy shape that continuously protrudes in a circumferential direction toward the high-pressure side, and a low-pressure side circumferential groove configured in a wavy shape that continuously protrudes in a circumferential direction toward the low-pressure side.

2. An end face seal assembly according to claim 1 wherein said radial groove is disposed between adjacent two of said circumferential grooves and/or on a low pressure side of said circumferential grooves adjacent a low pressure side.

3. The face seal assembly of claim 2 wherein said radial grooves are configured in a plurality of radially sequential sets, each set having a plurality of circumferentially spaced apart radial grooves, said circumferential grooves being radially sequential to said radial grooves.

4. A face seal assembly according to claim 3 wherein adjacent two sets of said radial grooves are staggered circumferentially.

5. The face seal assembly of claim 4 wherein at least one of said circumferential groove formations is circumferentially continuous in a convex wave shape toward either the high pressure side or the low pressure side.

6. The face seal assembly of claim 1 wherein said high pressure side circumferential groove has a plurality of first trough portions adjacent to a low pressure side and said low pressure side circumferential groove has a plurality of second trough portions adjacent to a high pressure side, said first and second trough portions being disposed radially opposite one another with a radial groove disposed therebetween.

7. The face seal assembly of claim 1, wherein the radial groove is provided in the first face and/or the second face.

8. The face seal assembly of claim 1, wherein the circumferential groove has a depth d1 and the radial groove has a depth d2, and wherein: d1 is more than or equal to 0.05mm and less than or equal to 2mm, d2 is more than or equal to 0.05mm and less than or equal to 2mm.

9. The face seal assembly of claim 1, wherein the circumferential groove has a width D1 and the radial groove has a width D2, and wherein: d1 is more than or equal to 0.1mm and less than or equal to 2mm, D2 is more than or equal to 0.1mm and less than or equal to 2mm.

10. The face seal assembly of claim 1, wherein the circumferential groove is configured as a plurality of wave segments, fold segments, or curves that are circumferentially continuous.

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