A double-end cartridge mechanical seal

Abstract

The present invention discloses a double-end face cartridge mechanical seal, comprising a shaft sleeve, a stationary ring seat and a sealing seat, the outer sleeve of the shaft sleeve is provided with a main seal and an auxiliary seal, and the two ends of the main seal are respectively sealed and fitted between one end of the shaft sleeve and the stationary ring seat; the end of the sealing seat close to the main seal is provided with a sealing cavity, and the auxiliary seal is fitted in the sealing cavity; the main seal comprises an active ring, a main stationary ring and a main stationary ring seat, the tail end of the active ring is installed in a first mounting groove, the end of the stationary ring seat close to the active ring is provided with a second mounting groove, and the tail end of the main stationary ring seat is installed in the second mounting groove; the other end of the main stationary ring seat is provided with a third mounting groove, the end of the main stationary ring away from the active ring is slidably fitted in the third mounting groove, and an elastic compensation component is provided between the bottom of the third mounting groove and the tail end of the main stationary ring. The present invention discloses a double-end face cartridge mechanical seal, which is easy to install and maintain, has stable performance and a wide range of applications.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical seals, in particular to a double-end-face cartridge type mechanical seal. Background Art

[0002] The working conditions of screw pump equipment are complex and are used in many different industries. They have high requirements for mechanical seals. Sanitary twin-screw pumps have even higher requirements for seals. Traditional mechanical seals for twin-screw pumps are mostly tandem double-end mechanical seals or back-to-back double-end mechanical seals, usually composed of two sets of standard mechanical seals.

[0003] Commonly used shaft seals for screw pumps include packing seals, labyrinth seals, and mechanical seals. Mechanical seals are further divided into wet contact mechanical seals and dry non-contact mechanical seals.

[0004] 1. Packing seal: Although it has the advantages of simple structure, easy maintenance and low cost, it has the disadvantages of short service life, large leakage and easy wear, which cannot be solved. It can no longer meet the sealing requirements of current process twin-screw compressors. This relatively primitive shaft seal form has been eliminated in mainstream process screw compressors.

[0005] 2. Labyrinth seal: It has the advantages of simple structure and low cost. However, it also has the disadvantages of short service life, large leakage (which gradually increases with the use time), and high energy consumption (it needs to continuously pass the isolation gas). Under the increasingly stringent environmental protection and energy-saving requirements, labyrinth seals are also difficult to meet the higher use requirements of process screw compressors. Its use ratio is gradually decreasing and has reached a relatively low level.

[0006] 3. Mechanical seal: Mechanical seal has the advantages of small leakage, long service life, energy saving and environmental protection, simple maintenance, etc., but it also has disadvantages such as relatively complex structure, high parts cost, high installation technology requirements, lack of targeted design, etc. However, compared with shaft seals, it has very small leakage and smaller shaft power consumption, which meets the current energy-saving and environmental protection requirements of the entire society. Mechanical seals have become the main shaft sealing method for process screw compressors.

[0007] In the existing double-end mechanical seal structure used in screw pumps, the main seal generally adopts a static ring compensation structure. However, the existing main static ring structure is fitted in the static ring seat through a sealing ring, and then a corresponding elastic compensation element is arranged at the tail of the main static ring. This structure has poor anti-sway performance during the main static ring compensation sliding process and is prone to getting stuck, resulting in inadequate compensation and leakage. Especially in high-speed operation conditions, the compensation for the main static ring is not smooth, resulting in weakened sealing performance of the sealing surface and a risk of leakage. Summary of the invention

[0008] A technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a double-end-face cartridge mechanical seal which is easy to install and maintain, has stable performance and a wide range of applications.

[0009] A technical solution adopted by the present invention is: to provide a double-end face cartridge mechanical seal, including a shaft sleeve, a stationary ring seat and a sealing seat, the shaft sleeve is slidably inserted into the inner holes of the stationary ring seat and the sealing seat, the outer sleeve of the shaft sleeve is provided with a main seal and an auxiliary seal, one end of the shaft sleeve is provided with a first mounting groove, and the two ends of the main seal are respectively and sealedly fitted between the first mounting groove and the stationary ring seat; one end of the sealing seat close to the main seal is provided with a sealing cavity, the stationary ring seat is fitted on the outer end face of the sealing seat close to the sealing cavity, and the auxiliary seal is fitted in the sealing cavity, and the shaft sleeve passing through the other end of the sealing seat is provided with a driving ring on the outside for realizing the driving connection between the shaft sleeve and the rotating shaft, and the end face of the driving ring is pressed against the end face of the sealing seat to realize the shaft sleeve, the main seal, the stationary ring seat, the auxiliary seal and the sealing seat are circumferentially assembled into an integrated structure;

[0010] The main seal includes an active ring, a main static ring and a main static ring seat, the tail end of the active ring is fitted in the first mounting groove, the end of the static ring seat close to the active ring is provided with a second mounting groove, and the tail end of the main static ring seat is fitted in the second mounting groove; the other end of the main static ring seat is provided with a third mounting groove, the end of the main static ring away from the active ring is slidably fitted in the third mounting groove, and an elastic compensation component is provided between the bottom of the third mounting groove and the tail end of the main static ring.

[0011] After adopting the above structure, the present invention has the following advantages compared with the prior art:

[0012] The mechanical seal structure of the present invention adopts an integral container structure, that is, a seal installation method that can be assembled and disassembled completely, which has low technical requirements for the installer, and the mechanical seal can be installed quickly and accurately, reducing the difficulty of seal installation and solving the probability of mechanical seal failure caused by installation factors; at the same time, it reduces the seal maintenance cost and saves maintenance time;

[0013] What is more critical is that in the structure of the present invention, the stationary ring of the main sealing part adopts a component form, that is, it includes a stationary ring and a stationary ring seat structure, which is connected with the corresponding mounting component through the stationary ring seat, the stationary ring slides in the stationary ring seat, and an elastic compensation component is arranged at the tail end of the stationary ring in the stationary ring seat, thereby realizing stable and smooth elastic compensation of the stationary ring, especially under high-speed operation conditions, the stationary ring compensation will not get stuck, thereby ensuring the stability of the sealing performance.

[0014] Furthermore, the auxiliary seal includes a secondary dynamic ring, a secondary dynamic ring seat and a secondary static ring, a fourth mounting groove is provided at the bottom of the sealing cavity, the tail end seal of the secondary static ring is mounted in the fourth mounting groove, the secondary dynamic ring seat is circumferentially positioned on the outside of the sleeve by a retaining ring, and a transmission screw is provided on the side wall of the secondary dynamic ring seat to realize the driving connection between the secondary dynamic ring seat and the rotating shaft; a fifth mounting groove is provided at one end of the secondary dynamic ring seat close to the secondary static ring, and one end of the secondary dynamic ring away from the secondary static ring is slidably fitted in the fifth mounting groove, and an elastic compensation component is provided between the bottom of the fifth mounting groove and the tail end of the secondary dynamic ring.

[0015] As an improvement, the sealing seat is provided with a liquid inlet hole and a liquid outlet hole connected to the sealing cavity, and the outer side of the auxiliary ring seat is sleeved with a pumping ring, and the outer wall of the pumping ring is provided with a spiral groove extending in the axial direction, and a gap is left between the outer wall of the pumping ring and the inner wall of the sealing cavity. This structure effectively enhances the circulation of the coolant or isolation liquid in the sealing cavity and improves the cooling effect of the sealing grinding surface.

[0016] In a further improvement, a limiting plate is integrally formed at one end of the pumping ring away from the auxiliary moving ring, and the rear end of the auxiliary moving ring seat rests on the limiting plate; the limiting plate is provided with at least two symmetrically arranged limiting protrusions, and the rear end of the auxiliary moving ring seat is provided with a limiting groove that matches the limiting protrusions. This improved structure enhances the radial limiting effect of the auxiliary moving ring seat and the pumping ring, and relative sliding is not likely to occur between the pumping ring and the auxiliary moving ring seat during the rotation process, thereby ensuring the movement stability of the pumping ring.

[0017] Further improved, the outer wall of the sleeve and the inner hole of the main static ring seat are integrally formed with an annular boss, and the outer side of the annular boss is provided with a pumping spiral groove extending in the axial direction. In this improved structure, a pumping spiral groove is also provided on the outer wall of the sleeve at the end near the main seal and the inner hole of the main static ring seat, which further enhances the circulation of the coolant or isolation liquid, improves the cooling efficiency, and also accelerates the flushing of particles on the sealing surface, reduces the wear of the sealing surface by solid particles in the medium, and increases the service life of the sealing surface.

[0018] In a further improvement, the end surface of the sealing seat facing away from the sealing cavity is provided with a plurality of stop blocks detachably arranged along the circumferential direction, and the outer wall of the shaft sleeve is provided with a stop groove for the end of the stop block to cooperate with, so as to limit the working height of the entire mechanical seal. In this improved structure, the stop structure is simple, and the stop groove is directly arranged on the side wall of the shaft sleeve, so that the limit of the working height of the entire mechanical seal is more accurate and stable.

[0019] In a further improvement, a limit baffle is provided at one end of the driving ring. When the driving ring is sleeved on the outside of the shaft sleeve, the limit baffle abuts against the end surface of the shaft sleeve to achieve axial limit. The limit baffle added in this improved structure is more convenient for the installation of the driving ring, and the axial position can be positioned after it is installed in place. It is quick and convenient to adjust the position of the radial driving element by rotating the driving ring.

[0020] Further improved, at least two symmetrically distributed anti-rotation pins are provided at the bottom of the second mounting groove, and the tail end of the main static ring seat is provided with an anti-rotation pin hole that cooperates with the anti-rotation pin. This improved structure further ensures that the main static ring seat will not deflect under the rotation of the active ring, thereby ensuring the stability of the main sealing surface.

[0021] Further improved, the first installation groove is a step groove, and a driving pin is provided in the first installation groove, and a driving pin groove matching with the driving pin is provided at the rear end of the active ring; an annular skirt is provided on the outer side wall of the end of the active ring near the friction surface, and when the active ring is mounted in the first installation groove, a disassembly gap is left between the annular skirt and the outer end surface of the first installation groove. This structure ensures that the active ring can rotate synchronously with the shaft sleeve, and the annular skirt is provided on the end surface of the active ring, which makes it more convenient to remove the active ring from the first installation groove during maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a cross-sectional view of the double-end-face cartridge mechanical seal of the present invention.

[0023] Figure 2 yes Figure 1 The X in the figure zooms in on the structure.

[0024] Figure 3 It is an installation structure diagram of the auxiliary dynamic ring and the auxiliary dynamic ring seat in the present invention.

[0025] Figure 4 It is a structural diagram of the pumping ring in the present invention.

[0026] Figure 5 yes Figure 1 Enlarge the structure diagram at Y in the figure.

[0027] Figure 6 It is a structural diagram of the main static ring in the present invention.

[0028] Among them, 01-main seal, 02-auxiliary seal; 03-elastic compensation component, 04-liquid inlet, 05-liquid outlet;

[0029] 1-sleeve, 1.1-first mounting groove, 2-stationary ring seat, 2.1-second mounting groove, 3-sealing seat, 3.1-sealing cavity, 3.2-fourth mounting groove, 4-driving ring, 4.1-limiting baffle, 5-active ring, 5.1-driving pin groove, 5.2-annular skirt, 6-main stationary ring, 6.1-limiting groove, 6.2-annular boss, 7-main stationary ring seat, 7.1-third mounting groove, 7.2-limiting Protrusion, 7.3-spring hole, 8-auxiliary dynamic ring, 9-auxiliary dynamic ring seat, 9.1-fifth mounting groove, 10-auxiliary static ring, 11-circuit ring, 12-pumping ring, 13-limiting plate, 13.1-limiting protrusion, 14-limiting block, 15-anti-rotation pin, 16-driving pin, 17-transmission screw, 18-driving screw, 19-fastening screw, 20-small spring, 21-push ring, 22-circlip, 23-retaining ring. DETAILED DESCRIPTION

[0030] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0031] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "outside", "tail end", "outside", "inner side wall", "bottom", "front end" and the like are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", "third", "fourth" and "fifth" are only for the convenience of distinction and understanding, and have no specific or limited meanings. Among them, the tail end refers to the end that is away from the friction surface. For example, the tail end of the moving ring refers to the end of the moving ring that is away from the grinding surface. The front end refers to the end of the screw that is away from the screw head.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "fitting" 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, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] like Figure 1 , 2 As shown, the present invention provides a double-end face cartridge mechanical seal, comprising a shaft sleeve 1, a stationary ring seat 2 and a sealing seat 3. When working, the shaft sleeve 1 is sleeved on the outside of the rotating shaft, and the shaft sleeve 1 is rotationally driven and connected to the rotating shaft.

[0034] The sleeve 1 is slidably inserted into the inner holes of the stationary ring seat 2 and the sealing seat 3, and the outer sleeve of the sleeve 1 is provided with a main seal 01 and an auxiliary seal 02 to form a set of double-end mechanical seal structure. Specifically, the main seal 01 is mainly arranged at the medium end to play the main sealing role, and the auxiliary seal 02 is arranged on the side close to the atmosphere end, and an isolation sealing cavity is formed between the main seal 01 and the auxiliary seal 02, and a coolant or isolation liquid is passed into the isolation sealing cavity to flush and cool the sealing surface, and to take away the impurity particles in the medium during the continuous circulation process, thereby reducing the wear of the sealing surface and increasing the service life of the seal; in this structure, in case of leakage on the main seal 01 side, the leaked medium will first enter the isolation sealing cavity, and will not quickly leak to the atmosphere end under the action of the auxiliary seal 02, thereby increasing the buffer time for maintenance.

[0035] Specifically, a first mounting groove 1.1 is provided at one end of the shaft sleeve 1, and both ends of the main seal 01 are respectively sealed and mounted between the first mounting groove 1.1 and the stationary ring seat 2; a sealing cavity 3.1 is provided at one end of the sealing seat 3 close to the main seal, the stationary ring seat 2 is mounted on the outer end surface of the sealing seat 3 close to the sealing cavity 3.1, and the auxiliary seal 02 is mounted in the sealing cavity 3.1. A driving ring 4 is provided on the outside of the other end of the shaft sleeve 1 passing through the sealing seat 3 for realizing the driving connection between the shaft sleeve 1 and the rotating shaft. Specifically, a driving ring 4 is provided on the driving ring 4. A plurality of driving screws 18 are circumferentially arranged on the outer wall of the driving ring 4, and the front end portion of the driving screw 18 passes through the shaft sleeve 1 and is fastened to the side wall of the rotating shaft, thereby realizing the driving connection between the rotating shaft and the shaft sleeve 1; in addition, a plurality of fastening screws 19 are circumferentially arranged on the side wall of the driving ring 4, and the front end portion of each fastening screw 19 is connected to the side wall of the shaft sleeve 1, thereby realizing the fixed connection between the driving ring 4 and the shaft sleeve 1; and in this structure, the plurality of driving screws 18 and the plurality of fastening screws 19 are alternately arranged in sequence.

[0036] In this structure, when the drive ring 4 is fixedly connected to the outside of the sleeve 1, the end face of the drive ring 4 presses against the end face of the sealing seat 3 to realize the circumferential assembly of the sleeve 1, the main seal 01, the stationary ring seat 2, the auxiliary seal 02 and the sealing seat 3 into an integrated structure, thereby realizing the container structure of the whole set of mechanical seals, that is, all parts can be pre-installed in the integral structure before installation, and when installed in the pump chamber, the whole seal structure is directly sleeved along the inner hole of the sleeve 1 on the outside of the rotating shaft, and then the sealing seat 3 is fixed to the pump housing, which is very convenient. This method can avoid the situation of missing or wrong installation due to too many parts during on-site assembly. On the other hand, in this structure, a limit baffle 4.1 is provided at one end of the drive ring 4. When the drive ring 4 is sleeved on the outside of the sleeve 1, the limit baffle 4.1 presses against the end face of the sleeve 1 to realize axial limitation.

[0037] like Figure 2As shown, in this embodiment, the main seal 01 includes an active ring 5, a main static ring 6 and a main static ring seat 7. The tail end of the active ring 5 is mounted in the first mounting groove 1.1, and a corresponding sealing ring is provided between the outside of the active ring 5 and the inner side wall of the first mounting groove 1.1. More specifically, the first mounting groove 1.1 here is a step groove, and a driving pin 16 is provided in the first mounting groove 1.1. The tail end of the active ring 5 is provided with a driving pin groove 5.1 that matches the driving pin 16; the outer side wall of the active ring 5 near the friction surface is provided with an annular skirt 5.2. When the active ring 5 is mounted in the first mounting groove 1.1, a disassembly gap is left between the annular skirt 5.2 and the outer end surface of the first mounting groove 1.1.

[0038] In addition, such as Figure 1 , 5 As shown in Figures 6 and 7, a second mounting groove 2.1 is provided at one end of the stationary ring seat 2 near the active ring 5, and the tail end of the main stationary ring seat 7 is fitted in the second mounting groove 2.1; a third mounting groove 7.1 is provided at the other end of the main stationary ring seat 7, and one end of the main stationary ring 6 away from the active ring 5 is slidably fitted in the third mounting groove 7.1, and an elastic compensation component 03 is provided between the bottom of the third mounting groove 7.1 and the tail end of the main stationary ring 6. In this structure, in order to prevent the deflection of the main stationary ring seat 7, at least two symmetrically distributed anti-rotation pins 15 are provided at the bottom of the second mounting groove 7.1, and an anti-rotation pin hole 7.2 that matches the anti-rotation pin 15 is provided at the tail end of the main stationary ring seat 7. Specifically, a limiting protrusion 7.2 is provided on the inner side wall of the second mounting groove 7.1, and correspondingly, a limiting groove 6.1 matching with the limiting protrusion 7.2 and extending in the axial direction is provided on the outer side wall of the main static ring 6; more specifically, an annular boss 6.2 is also provided at the tail end of the main static ring 6, and the limiting groove 6.1 is opened on the annular boss 6.2, and a retaining spring groove 7.3 is provided on the inner side wall of the opening end of the second mounting groove 7.1, and a retaining spring 22 is installed in the retaining spring groove 7.3. In the natural state, the retaining spring 22 is limited and pressed against the end face of the annular boss 6.2 to prevent the main static ring 6 from being separated from the second mounting groove 7.1 in the axial direction. In this structure, a sealing groove 6.3 is provided on the inner side wall of the tail end of the main static ring 6, and a sealing ring is installed in the sealing groove 6.3, and the inner ring of the sealing ring is sealingly installed on the corresponding side wall of the second mounting groove 7.1. In order to prevent the sealing ring from being squeezed and deformed when the operating pressure is too high, thereby affecting the sealing performance, a retaining ring 23 is provided at the bottom of the sealing groove 6.3 in this structure to prevent the sealing ring from being squeezed and deformed.

[0039] On the other hand, the elastic compensation assembly 03 in this structure includes a plurality of small springs 20, a plurality of spring holes 7.3 are provided along the circumferential direction at the bottom of the second mounting groove 7.1, and a push ring 21 is provided at the tail end of the main static ring 6, one end of the plurality of small springs 20 is fitted in the spring hole 7.3, and the other end is pressed against the end surface of the push ring 21. In this structure, in order to prevent

[0040] like Figure 1 , 3 As shown, the auxiliary seal 02 includes a secondary moving ring 8, a secondary moving ring seat 9 and a secondary static ring 10. A fourth mounting groove 3.2 is provided at the bottom of the sealing cavity 3.1. The tail end of the secondary static ring 10 is sealably mounted in the fourth mounting groove 3.2. The secondary moving ring seat 9 is circumferentially positioned outside the sleeve 1 by a retaining ring 11, and a transmission screw 17 is provided on the side wall of the secondary moving ring seat 9 to achieve a driving connection between the secondary moving ring seat 9 and the rotating shaft. A fifth mounting groove 9.1 is provided at one end of the secondary moving ring seat 9 near the secondary static ring 10. The end of the secondary moving ring 8 away from the secondary static ring 10 is slidingly fitted in the fifth mounting groove 9.1, and an elastic compensation component 03 is provided between the bottom of the fifth mounting groove 9.1 and the tail end of the secondary moving ring 8. The sliding mounting structure of the secondary moving ring 8 and the secondary moving ring seat 9 in this structure is similar to the sliding mounting structure of the main static ring 6 and the main static ring seat 7 in the main seal, and will not be repeated here. In addition, the structure of the elastic compensation component 03 in this structure is the same as that of the elastic compensation component 03 in the main seal 01. The specific structure refers to the description of the main static ring 6 and the main static ring seat 7 structure, which will not be repeated here.

[0041] like Figure 1 As shown, in the structure of this embodiment, the sealing seat 3 is provided with a liquid inlet hole 04 and a liquid outlet hole 05 which are connected to the sealing cavity 3.1, and a pumping ring 12 is sleeved on the outer side of the auxiliary dynamic ring seat 9, and a spiral groove extending in the axial direction is provided on the outer side wall of the pumping ring 12; a gap is left between the outer side wall of the pumping ring 12 and the inner side wall of the sealing cavity 3.1.

[0042] like Figure 4 As shown, a limiting plate 13 is integrally formed at one end of the pumping ring 12 away from the auxiliary dynamic ring 8, and the rear end of the auxiliary dynamic ring seat 9 rests against the limiting plate 13; at least two symmetrically arranged limiting protrusions 13.1 are provided on the limiting plate 13, and a limiting groove 9.2 matching with the limiting protrusions 13.1 is provided at the rear end of the auxiliary dynamic ring seat 9. In this structure, in order to further ensure the fixed connection between the pumping ring 12 and the auxiliary dynamic ring seat 9, each limiting protrusion 13.1 on the limiting plate 13 is connected with the limiting groove 9.2 on the auxiliary dynamic ring seat 9 by interference fit.

[0043] like Figure 2 As shown, in order to further enhance the circulation of the liquid in the isolation sealing cavity, an annular boss 1.2 is integrally formed at the outer wall of the sleeve 1 and the corresponding position of the inner hole of the main static ring seat 7, and the outer side surface of the annular boss 1.2 is provided with a pumping spiral groove extending in the axial direction.

[0044] like Figure 1As shown, a plurality of limit blocks 14 are detachably provided along the circumferential direction on the end face of the sealing seat 3 facing away from the sealing chamber 3.1, and a limit groove 1.3 for the end of the limit block 13 to cooperate is provided on the outer wall of the sleeve 1, so as to limit the working height of the entire mechanical seal. During the installation process, when the integral mechanical seal structure that has been assembled and has a defined working height is installed in the pump chamber, after the sealing seat 3 and the pump body are fixed, the drive screw 18 on the drive ring 4 is tightened to the outside of the rotating shaft, and then the limit block 13 is removed, thereby ensuring that the containerized mechanical seal is at the preset working height position after installation, which is convenient and accurate, does not require the working height to be adjusted again, is simple and efficient. The working height of the mechanical seal refers to the compression height of the springs in each elastic compensation component in the entire set of mechanical seal structures, that is, under this compression height, the elastic performance of the mechanical seal meets the design requirements.

[0045] The above is an explanation of the preferred embodiments of the present invention, but it cannot be understood as a limitation of the claims. The present invention is not limited to the above embodiments, and its specific structure is allowed to be changed. All changes made within the scope of protection of the independent claims of the present invention are within the scope of protection of the present invention.

Claims

1. A double-end-face cartridge mechanical seal, comprising a sleeve (1), a stationary ring seat (2) and a sealing seat (3), wherein the sleeve (1) is slidably inserted into the inner holes of the stationary ring seat (2) and the sealing seat (3), and the outer sleeve of the sleeve (1) is provided with a main seal (01) and an auxiliary seal (02), characterized in that: A first mounting groove (1.1) is provided at one end of the shaft sleeve (1), and both ends of the main seal (01) are respectively and sealedly mounted between the first mounting groove (1.1) and the stationary ring seat (2); a sealing cavity (3.1) is provided at one end of the sealing seat (3) close to the main seal (01), the stationary ring seat (2) is mounted on the outer end surface of the sealing seat (3) close to the sealing cavity (3.1), and the auxiliary seal (02) is mounted in the sealing cavity (3.1); a driving ring (4) is provided on the outside of the other end of the shaft sleeve (1) passing through the sealing seat (3) for realizing the driving connection between the shaft sleeve (1) and the rotating shaft, and the end surface of the driving ring (4) is pressed against the end surface of the sealing seat (3) to realize the shaft sleeve (1), the main seal (01), the stationary ring seat (2), the auxiliary seal (02) and the sealing seat (3) are assembled into an integrated structure along the circumferential direction; The main seal (01) comprises an active ring (5), a main static ring (6) and a main static ring seat (7); the tail end of the active ring (5) is mounted in a first mounting groove (1.1); the end of the static ring seat (2) close to the active ring (5) is provided with a second mounting groove (2.1); the tail end of the main static ring seat (7) is mounted in the second mounting groove (2.1); the other end of the main static ring seat (7) is provided with a third mounting groove (7.1); the end of the main static ring (6) away from the active ring (5) is slidably fitted in the third mounting groove (7.1), and an elastic compensation component (03) is provided between the bottom of the third mounting groove (7.1) and the tail end of the main static ring (6); The auxiliary seal (02) comprises a secondary dynamic ring (8), a secondary dynamic ring seat (9) and a secondary static ring (10); a fourth mounting groove (3.2) is provided at the bottom of the sealing cavity (3.1); the tail end seal of the secondary static ring (10) is mounted in the fourth mounting groove (3.2); the secondary dynamic ring seat (9) is circumferentially positioned on the outside of the shaft sleeve (1) by a retaining ring (11); and a transmission screw (17) is provided on the side wall of the secondary dynamic ring seat (9) to realize the driving connection between the secondary dynamic ring seat (9) and the rotating shaft; a fifth mounting groove (9.1) is provided at one end of the secondary dynamic ring seat (9) close to the secondary static ring (10); and a fifth mounting groove (9.1) is provided at one end of the secondary dynamic ring seat (9) away from the secondary static ring (10) for sliding engagement. The active ring (5) is fitted in the fifth mounting groove (9.1), and an elastic compensation component (03) is provided between the bottom of the fifth mounting groove (9.1) and the rear end of the auxiliary active ring (8); the first mounting groove (1.1) is a step groove, and a driving pin (16) is provided in the first mounting groove (1.1), and a driving pin groove (5.1) matching with the driving pin (16) is provided at the rear end of the active ring (5); an annular skirt (5.2) is provided on the outer side wall of the end close to the friction surface of the active ring (5), and when the active ring (5) is mounted in the first mounting groove (1.1), a disassembly clearance is left between the annular skirt (5.2) and the outer end surface of the first mounting groove (1.1).

2. The double-end cartridge mechanical seal according to claim 1, characterized in that: The sealing seat (3) is provided with a liquid inlet hole (04) and a liquid outlet hole (05) which are connected to the sealing cavity (3.1), and the outer side of the auxiliary dynamic ring seat (9) is sleeved with a pumping ring (12), and the outer side wall of the pumping ring (12) is provided with a spiral groove extending in the axial direction; a gap is left between the outer side wall of the pumping ring (12) and the inner side wall of the sealing cavity (3.1).

3. The double-end cartridge mechanical seal according to claim 2, characterized in that: A limiting plate (13) is integrally formed at one end of the pumping ring (12) away from the auxiliary moving ring (8), and the rear end of the auxiliary moving ring seat (9) rests against the limiting plate (13); at least two symmetrically arranged limiting protrusions (13.1) are provided on the limiting plate (13), and the rear end of the auxiliary moving ring seat (9) is provided with a limiting groove (9.2) that matches the limiting protrusion (13.1).

4. The double-end cartridge mechanical seal according to claim 2, characterized in that: An annular boss (1.2) is integrally formed at a position corresponding to the outer wall of the shaft sleeve (1) and the inner hole of the main stationary ring seat (7), and the outer side surface of the annular boss (1.2) is provided with a pumping spiral groove extending in the axial direction.

5. The double-end cartridge mechanical seal according to claim 1, characterized in that: A plurality of limit blocks (14) are detachably provided along the circumferential direction on the end surface of the sealing seat (3) facing away from the sealing cavity (3.1), and a limit groove (1.3) for the end of the limit block (13) to cooperate with is provided on the outer wall of the shaft sleeve (1) to limit the working height of the entire mechanical seal.

6. The double-end cartridge mechanical seal according to claim 1, characterized in that: A limit baffle (4.1) is provided at one end of the drive ring (4); when the drive ring (4) is sleeved on the outside of the shaft sleeve (1), the limit baffle (4.1) abuts against the end surface of the shaft sleeve (1) to achieve axial limit.

7. The double-end cartridge mechanical seal according to claim 1, characterized in that: At least two symmetrically distributed anti-rotation pins (15) are provided at the bottom of the second mounting groove (7.1), and an anti-rotation pin hole (7.2) cooperating with the anti-rotation pin (15) is provided at the rear end of the main stationary ring seat (7).

Images