Double-end-face high-pressure-resistant mechanical seal
By exchanging the positions of the inner gasket and the O-ring in the double-end mechanical seal and deepening the inner groove of the dynamic ring, the problem of the O-ring squeezing into the gap between the push ring and the sleeve under high pressure is solved, achieving effective sealing and wide applicability of high-pressure pumps.
Patent Information
- Application Number
- CN202423111083.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2025-10-10
- Estimated Expiration
- 2034-12-17
AI Technical Summary
The inner mechanical seal of the existing pressurized double-end mechanical seal for high-pressure pumps is prone to the problem that the O-ring is squeezed into the gap between the push ring and the sleeve, affecting the floating performance of the dynamic ring and even causing medium leakage.
In a double-face mechanical seal, the gasket and O-ring of the inner mechanical seal are interchanged, the gasket thickness is increased and the groove inside the dynamic ring is deepened to ensure that the gasket is located inside the O-ring, preventing the O-ring from deforming and squeezing into the gap between the push ring and the sleeve under high pressure. A high-pressure resistant design is used in combination with the inner and outer mechanical seals.
It effectively prevents O-rings from being damaged under high pressure, ensures the sealing effect, is suitable for high-pressure pumps, expands the scope of use, and prevents the medium in the equipment from leaking out.
Smart Images
Figure CN223424640U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of mechanical seals, in particular to a double-end-face high-pressure resistant mechanical seal used in a pressurized outer sealing cavity to prevent leakage of a medium in equipment under harsh working conditions. Background Art
[0002] Mechanical seals are a new type of shaft sealing device with excellent sealing performance and long service life. They are used in the shaft end seals of pump equipment used in the oil refining and chemical industries. During operation, a mechanical seal can leak a very small amount of media between the friction pairs. The petroleum and petrochemical industries operate under complex conditions, with many flammable, explosive, toxic, and high-temperature, easily vaporized media. Single-end mechanical seals are no longer sufficient for these complex conditions, and double-end mechanical seals are necessary to ensure that if one mechanical seal fails, the other set remains operational. For media with higher risk factors, an isolation fluid with a higher pressure than the media inside the pump must be added between the double-end mechanical seals. This ensures that any leakage between the friction pairs during normal pump operation is simply the high-pressure isolation fluid leaking into the pump, rather than the low-pressure media leaking out.
[0003] Commonly used ordinary double-end mechanical seals are composed of two sets of ordinary single-end mechanical seals. The working condition of ordinary single-end mechanical seal design is that the pressure inside the sealing chamber is higher than the pressure outside the sealing chamber (that is, the atmospheric pressure outside the sealing cover), while the working condition of the inner mechanical seal in the pressurized double-end mechanical seal is that the pressure inside the sealing chamber is lower than the pressure outside the sealing chamber. The medium pressure of the medium and low pressure equipment itself is not high, and even if the isolation fluid is pressurized, it will not have much impact on the mechanical seal. However, the pressure inside the high-pressure pump itself is relatively high, and the pressure after pressurization has exceeded the design pressure of ordinary mechanical seals. Therefore, the inner mechanical seal of the pressurized double-end mechanical seal used in the high-pressure pump often has the O-ring of the dynamic ring moving toward the spring seat after being pressurized. Under the action of high pressure, the O-ring squeezes into the gap between the push ring and the sleeve, thereby affecting the floating performance of the dynamic ring, and even the O-ring and the dynamic ring are separated, causing leakage, so that this structure can only be used for medium and low pressure equipment, and high-pressure pumps cannot be used. Utility Model Content
[0004] The purpose of the utility model is to provide a double-end face high-pressure resistant mechanical seal to address the deficiencies in the above-mentioned technology. The double-end face mechanical seal can ensure normal operation when the outer sealing chamber is pressurized and the pressure exceeds the maximum pressure that the original single-end face mechanical seal can withstand, thereby ensuring that the medium in the equipment does not leak outward under the action of the high-pressure isolation fluid in the outer sealing chamber.
[0005] In view of this, the utility model provides a double-end face high-pressure resistant mechanical seal, comprising a shaft sleeve, an inner gland, an outer gland, an inner mechanical seal and an outer mechanical seal; wherein, the shaft sleeve is fixedly sleeved on the outer circle of the equipment main shaft, the inner gland and the outer gland are installed on the outside of the equipment cavity from the inside to the outside, the inner gland and the equipment cavity form an inner sealing cavity, the inner mechanical seal is installed in the inner sealing cavity, the outer gland and the inner gland form an outer sealing cavity, the outer mechanical seal is installed in the outer sealing cavity, and the inner mechanical seal and the outer mechanical seal are both sleeved on the outer circle of the shaft sleeve; the outer mechanical seal is an ordinary single-end face mechanical seal, and the inner mechanical seal is a high-pressure resistant single-end face mechanical seal;
[0006] The inner mechanical seal includes a stationary ring and a dynamic ring assembly, the outer sealing ring of the stationary ring is installed in the groove of the inner pressure cover; the dynamic ring assembly includes a spring seat, several springs, a push ring, a gasket, an O-ring, a dynamic ring and several transmission screws; the spring seat is fixed to the outer circle of the shaft sleeve, the spring seat is provided with several stepped spring holes and several stepped through holes opposite to the spring holes, the springs are installed in the spring holes of the spring seat and abut against the inner side of the push ring, the transmission screws pass through the stepped through holes of the spring seat and are riveted to the inner through holes of the push ring and drive the push ring and the spring seat to rotate together; the outer side of the push ring is provided with several inwardly protruding arc-shaped protrusions, the inner side of the outer circle of the dynamic ring is provided with several arc-shaped grooves, the arc-shaped protrusions of the push ring match the arc-shaped grooves of the dynamic ring; the inner groove of the dynamic ring is provided with a gasket and an O-ring, and the gasket is arranged on the inner side of the O-ring.
[0007] Preferably, the outer mechanical seal includes a static ring 2 and a dynamic ring assembly 2, and the outer sealing ring of the static ring 2 is installed in the groove of the outer pressure cover; the dynamic ring assembly 2 includes a spring seat 2, several springs, a push ring 2, a gasket 2, an O-ring 2, a dynamic ring 2 and several transmission screws; the spring seat 2 is fixed to the outer circle of the shaft sleeve, and the spring seat 2 is provided with several stepped spring holes and several stepped through holes opposite to the spring holes, and the springs are installed in the spring holes of the spring seat 2 and abut against the inner side of the push ring 2, and the transmission screws pass through the stepped through holes of the spring seat 2 and are riveted to the inner through holes of the push ring 2; the outer side of the push ring 2 is provided with several inwardly protruding arc-shaped protrusions 2, and the inner side of the outer circle of the dynamic ring 2 is provided with several arc-shaped grooves 2, and the arc-shaped protrusions 2 of the push ring 2 match the arc-shaped grooves 2 of the dynamic ring 2; the inner groove of the dynamic ring 2 is equipped with a gasket 2 and an O-ring 2, and the gasket 2 is arranged on the outside of the O-ring 2.
[0008] Preferably, the depth of the inner groove of the first moving ring is greater than the depth of the inner groove of the second moving ring.
[0009] Preferably, the thickness of the washer 1 is greater than the compressible distance of the spring; the depth of the inner groove of the dynamic ring 1 is greater than the sum of the thickness of the washer 1 and the cross-sectional length of the O-ring 1 in the working state.
[0010] The beneficial effects of the utility model are:
[0011] 1. The double-end high-pressure mechanical seal of the utility model is an improvement on the structure of the existing mechanical seal by deepening the groove on the back of the dynamic ring, thickening the gasket, and exchanging the positions of the gasket and the O-ring. The installation dimensions are not changed, the applicability is strong, and the improvement method is simple and easy to operate.
[0012] 2. The double-end face high-pressure resistant mechanical seal of the utility model interchanges the positions of the gasket and the O-ring in the original ordinary mechanical seal. The gasket is located on the inner side of the O-ring, which prevents the O-ring in the inner mechanical seal from being locally deformed and squeezed into the gap between the push ring and the shaft sleeve under the action of the high-pressure isolation fluid in the outer sealing chamber. The thickness of the gasket is greater than the compressible distance of the spring, which can ensure that even if the gasket and the push ring move toward the inner sealing chamber under the push of the outer high-pressure isolation fluid, causing the spring to be completely compressed into the spring hole, the gasket will not fall out of the dynamic ring groove and will be padded on the inner side of the dynamic ring and cannot be reset, thereby solving the problem of the inner mechanical seal of the original pressurized double-end face mechanical seal for high-pressure pumps, in which the O-ring of the dynamic ring often moves toward the spring seat after being pressurized, and the O-ring squeezes into the gap between the push ring and the shaft sleeve under the action of high pressure, thereby affecting the floating performance of the dynamic ring, and even the O-ring and the dynamic ring are separated, causing leakage.
[0013] 3. The double-end face high-pressure resistant mechanical seal of the utility model adopts a combination of an inner mechanical seal and an outer mechanical seal, so that the pressure resistance of the device is stronger and it is used in high-pressure pumps with a wider range of applications.
[0014] 4. The double-end face high-pressure resistant mechanical seal of the utility model has a simple structure and a low price, and does not increase the user's operating costs.
[0015] 5. The double-end high-pressure mechanical seal of the utility model can ensure normal operation when the outer sealing chamber is pressurized and the pressure exceeds the maximum pressure that the original single-end mechanical seal can withstand, thereby ensuring that the medium in the equipment does not leak outward under the action of the high-pressure isolation fluid in the outer sealing chamber. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a cross-sectional front view of the overall structure of the double-end high-pressure resistant mechanical seal of the utility model;
[0017] Figure 2 This is a cross-sectional front view of the inner mechanical seal structure of the utility model;
[0018] Figure 3 This is a structural inside view of the spring seat 1 of the present invention;
[0019] Figure 4 For the utility model Figure 3 Middle AA section;
[0020] Figure 5 This is an outside view of the push ring structure of the present invention;
[0021] Figure 6 For the utility model Figure 5 Middle BB cross-section;
[0022] Figure 7 This is an inner side view of the dynamic ring structure of the present invention;
[0023] Figure 8 For the utility model Figure 7 mid-CC cross-section;
[0024] In the figure: 1. sleeve; 2. inner pressure cover; 3. outer pressure cover; 4. inner sealing chamber; 5. outer sealing chamber; 6. inner mechanical seal; 61. spring seat; 62. spring; 63. push ring; 631. arc-shaped protrusion; 64. gasket; 65. O-ring; 66. moving ring; 661. arc-shaped groove; 662. inner groove of moving ring; 67. stationary ring; 68. transmission screw; 7. outer mechanical seal. DETAILED DESCRIPTION
[0025] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.
[0026] See also Figure 1 and Figure 2 The utility model provides a double-end face high-pressure resistant mechanical seal, including a sleeve 1, an inner gland 2, an outer gland 3, an inner mechanical seal 6 and an outer mechanical seal 7; wherein, the sleeve 1 is fixedly sleeved on the outer circle of the equipment main shaft, the inner gland 2 and the outer gland 3 are installed on the outside of the equipment cavity from the inside to the outside, the inner gland 2 and the equipment cavity form an inner sealing cavity 4, the inner mechanical seal 6 is installed in the inner sealing cavity 4, the outer gland 3 and the inner gland 2 form an outer sealing cavity 5, the outer mechanical seal 7 is installed in the outer sealing cavity 5, and the inner mechanical seal 6 and the outer mechanical seal 7 are both sleeved on the outer circle of the sleeve 1; the outer mechanical seal 7 is an ordinary single-end face mechanical seal, and the inner mechanical seal 6 is a high-pressure resistant single-end face mechanical seal.
[0027] In this embodiment, the device housing and the main shaft form the device cavity. Along the axial direction of the main shaft, the side closer to the device cavity is defined as "inner" or "inside," and the side farther from the device cavity is defined as "outer" or "outside." Shaft sleeve 1 drives dynamic ring assembly 1 in inner mechanical seal 6 and dynamic ring assembly 2 in outer mechanical seal 7 to rotate together.
[0028] See also Figures 2 to 8 As shown, the inner mechanical seal 6 includes a stationary ring 67 and a dynamic ring assembly 1. The outer seal ring of the stationary ring 67 is installed in the groove of the inner pressure cover 2; the dynamic ring assembly 1 includes a spring seat 61, a plurality of springs 62, a push ring 63, a gasket 64, an O-ring 65, a dynamic ring 66 and a plurality of transmission screws 68; the spring seat 61 is fixed to the outer circle of the shaft sleeve 1, and the spring seat 61 is provided with a plurality of stepped spring holes and a plurality of stepped through holes opposite to the spring holes. The spring 62 is installed in the spring hole of the spring seat 61 and abuts against the inner side of the push ring 63 The driving screw 68 passes through the stepped through hole of the spring seat 61 and is riveted to the inner through hole of the push ring 63, driving the push ring 63 and the spring seat 61 to rotate together; the outer side of the push ring 63 is provided with a plurality of inwardly protruding arc-shaped protrusions 631, and the inner side of the outer circle of the movable ring 66 is provided with a plurality of arc-shaped grooves 661, and the arc-shaped protrusions 631 of the push ring 63 match the arc-shaped grooves 661 of the movable ring; the inner groove 662 of the movable ring is equipped with a washer 64 and an O-ring 65, and the washer 64 is arranged on the inner side of the O-ring 65.
[0029] In this embodiment, the stationary ring (67) is mounted on the outside of the dynamic ring assembly (1); the spring seat (61) is screwed to the outer circumference of the sleeve (1), which drives the spring seat (61) in rotation. The spring seat (61) drives the push ring (63) in rotation via a drive screw (68) riveted to the push ring (63). The push ring (63) drives the dynamic ring (66) in rotation via its arc-shaped protrusion (631), which mates with the arc-shaped groove (661) on the dynamic ring (66). The inner groove (662) of the dynamic ring (1) is a hole located on the side of the dynamic ring (66) parallel to the friction surface, i.e., on the end face of the dynamic ring (66) near the device cavity. This hole is used to mount the washer (64) and O-ring (65).
[0030] The outer mechanical seal 7 includes a static ring 2 and a dynamic ring assembly 2. The outer sealing ring of the static ring 2 is installed in the groove of the outer pressure cover 3; the dynamic ring assembly 2 includes a spring seat 2, several springs 62, a push ring 2, a gasket 2, an O-ring 2, a dynamic ring 2 and several transmission screws 68; the spring seat 2 is fixed to the outer circle of the shaft sleeve 1, and the spring seat 2 is provided with several stepped spring holes and several stepped through holes opposite to the spring holes. The spring 62 is installed in the spring hole of the spring seat 2 and abuts against the inner side of the push ring 2. The transmission screw 68 passes through the stepped through hole of the spring seat 2 and is riveted to the inner through hole of the push ring 2; the outer side of the push ring 2 is provided with several inwardly protruding arc-shaped protrusions 2, and the inner side of the outer circle of the dynamic ring 2 is provided with several arc-shaped grooves 2. The arc-shaped protrusions 2 of the push ring 2 match the arc-shaped grooves 2 of the dynamic ring 2; the inner groove of the dynamic ring 2 is equipped with a gasket 2 and an O-ring 2, and the gasket 2 is arranged on the outside of the O-ring 2.
[0031] In this embodiment, the second stationary ring is mounted outside the second dynamic ring assembly; the second spring seat is screwed to the outer circumference of the sleeve 1, which drives the second spring seat in rotation. The second spring seat drives the second push ring via a drive screw 68 riveted to the second push ring. The second push ring drives the second dynamic ring via its arc-shaped protrusion, which mates with its arc-shaped groove. The inner groove of the second dynamic ring is a hole located on the side of the second dynamic ring parallel to the friction surface, i.e., on the side of the second dynamic ring closest to the device cavity. This hole is used to mount the second washer and the second O-ring.
[0032] The depth of the inner groove 662 of the first rotating ring is greater than the depth of the inner groove of the second rotating ring.
[0033] In this embodiment, the inner groove 662 of the rotating ring 1 is a three-stage stepped through-hole. The thickness b of the washer 1 64 is greater than the compressible distance d of the spring 62, i.e., b>d. Furthermore, the inner hole of the washer 1 64 maintains a small clearance fit with the outer diameter of the sleeve 1. The depth a of the inner groove 662 of the rotating ring 1 is greater than the sum of the thickness b of the washer 1 and the cross-sectional length c of the O-ring 1 65 in the operating state, i.e., a>b+c. This ensures that the O-ring 1 65 has a certain degree of freedom within the inner groove 662 of the rotating ring 1, protecting the rotating ring 1 66 from being swollen to death by the O-ring 1 65.
[0034] The working principle of the above-mentioned double-face high-pressure mechanical seal is as follows: Because the O-ring is made of rubber and is compressible, it will deform under pressure to seal small gaps. In high-pressure working conditions, in order to prevent the O-ring from deforming too much under high pressure and causing damage, a gasket is often installed on the low-pressure side to protect it and improve its stress state. Generally, the pressure in the pump chamber of a pump mechanical seal is higher than the pressure on the atmospheric side. Therefore, in ordinary single-face mechanical seals, the gasket is set between the O-ring and the dynamic ring. Toxic and harmful media, especially those with strong hazards, in order to completely prevent the leakage of media in the equipment cavity, double-face mechanical seals are used in this working condition. The outer sealing chamber is filled with an isolation fluid, and the isolation fluid pressure is greater than the pressure of the media in the inner sealing chamber, ensuring that the isolation fluid can only flow into the equipment and that toxic and harmful media in the equipment will not leak out. Therefore, the force on the O-ring 1 65 of the inner mechanical seal 6 is opposite to the force on the O-ring 2 of the outer mechanical seal 7. If the gasket 2 is still arranged between the O-ring 2 and the dynamic ring 2 like the outer mechanical seal 7, the gasket 1 64 will lose its original function of cushioning the low-pressure side of the O-ring 1 65 to protect it. This situation is more obvious in high-pressure pumps. In addition, for riveting the drive screw 68, the push ring 1 63 is also processed with rivet holes for riveting the drive screw 68. After the drive screw 68 is riveted to the push ring 1 63, holes are left on its end face. If the O-ring 1 65 is directly and tightly fitted with the push ring 1 63 under pressure, the O-ring 1 65 is easily squeezed into these holes and damaged. To this end, the present invention improves the inner mechanical seal 6 and arranges a gasket 64 between the push ring 63 and the O-ring 65. The gap between the inner hole of the gasket 64 and the shaft sleeve 1 is small, and the gap between the outer circle of the gasket 64 and the inner groove 662 of the dynamic ring is small. This can prevent the soft O-ring 65 from being excessively deformed and squeezed into the gap between the push ring 63 and the shaft sleeve 1 under the high pressure on the back, causing damage to the O-ring 65 and the push ring 63 being squeezed and unable to move along the shaft sleeve 1. At the same time, the thickened gasket 64 is blocked between the O-ring 65 and the push ring 63, and the O-ring 65 does not directly contact the surface of the push ring 63, so as to prevent the O-ring 65 from being damaged by the holes on the surface of the push ring 63 and allow the gasket 64 to improve the stress state of the O-ring 65.
[0035] The working process of the above-mentioned double-end face high-pressure mechanical seal is as follows:
[0036] The isolation liquid in the outer sealing chamber 5 is pressurized, and its pressure is higher than the pressure in the equipment sealing chamber, that is, the inner sealing chamber 4. Since the pressure in the outer sealing chamber 5 is higher than the pressure on the outer side of the outer gland 3 (that is, atmospheric pressure), the O-ring 2 in the inner groove of the dynamic ring 2 in the outer mechanical seal 7 is pushed toward the atmospheric end by the pressure in the outer sealing chamber. The gasket 2 placed on the outer side of the O-ring 2 prevents it from being squeezed into the gap between the inner groove of the dynamic ring 2 and the outer circle of the sleeve 1. The high-pressure isolation liquid in the outer sealing chamber 5 enters the inner portion of the static ring 1 67 in the inner mechanical seal 6. The gap between the hole and the outer circle of the sleeve 1, on the one hand, prevents the toxic and harmful media in the sealing cavity of the equipment from leaking to the outer sealing cavity 5 through the friction pair of the dynamic and static rings of the inner mechanical seal 6 (it can only leak to the inside of the equipment and cannot leak to the outer sealing cavity 5); on the other hand, it pushes the O-ring 65 and the gasket 64 to move toward the inside of the equipment. In order to prevent the O-ring 65 from being pushed out of the inner groove 662 of the dynamic ring and being padded between the dynamic ring 66 and the push ring 63, the dynamic ring 66 cannot float with the rotation of the main shaft of the equipment. Compared with the outer mechanical seal 7, the installation positions of the gasket and the O-ring in the inner mechanical seal 6 are changed, that is, the gasket 64 is moved from the outside of the O-ring 65 to the inside of the O-ring 65. Since the original gasket is thin, if the medium pressure fluctuates greatly, the spring 62 of the inner mechanical seal 6 is completely compressed into the spring hole of the spring seat 61, which will cause the gasket 64 to fall out of the inner groove 662 of the dynamic ring. Therefore, the gasket 64 is thickened and the depth of the inner groove 662 of the dynamic ring is increased to ensure that no matter how the medium pressure fluctuates, the gasket 64 and the O-ring 65 can be in the normal working position and will not fall out. Once the medium pressure returns to normal, the gasket 64 and the O-ring 65 can quickly return to their original positions to ensure normal operation of the equipment.
Claims
1. A double-end high-pressure mechanical seal, characterized in that: It includes a shaft sleeve, an inner gland, an outer gland, an inner mechanical seal and an outer mechanical seal; wherein, the shaft sleeve is fixedly sleeved on the outer circle of the equipment main shaft, the inner gland and the outer gland are installed on the outside of the equipment cavity from the inside to the outside, the inner gland and the equipment cavity form an inner sealing cavity, the inner mechanical seal is installed in the inner sealing cavity, the outer gland and the inner gland form an outer sealing cavity, the outer mechanical seal is installed in the outer sealing cavity, and the inner mechanical seal and the outer mechanical seal are both sleeved on the outer circle of the shaft sleeve; the outer mechanical seal is an ordinary single-end mechanical seal, and the inner mechanical seal is a high-pressure resistant single-end mechanical seal; The inner mechanical seal includes a stationary ring and a dynamic ring assembly, the outer sealing ring of the stationary ring is installed in the groove of the inner pressure cover; the dynamic ring assembly includes a spring seat, several springs, a push ring, a gasket, an O-ring, a dynamic ring and several transmission screws; the spring seat is fixed to the outer circle of the shaft sleeve, the spring seat is provided with several stepped spring holes and several stepped through holes opposite to the spring holes, the springs are installed in the spring holes of the spring seat and abut against the inner side of the push ring, the transmission screws pass through the stepped through holes of the spring seat and are riveted to the inner through holes of the push ring and drive the push ring and the spring seat to rotate together; the outer side of the push ring is provided with several inwardly protruding arc-shaped protrusions, the inner side of the outer circle of the dynamic ring is provided with several arc-shaped grooves, the arc-shaped protrusions of the push ring match the arc-shaped grooves of the dynamic ring; the inner groove of the dynamic ring is provided with a gasket and an O-ring, and the gasket is arranged on the inner side of the O-ring.
2. The double-end face high pressure resistant mechanical seal according to claim 1, characterized in that: The outer mechanical seal includes a static ring 2 and a dynamic ring assembly 2, and the outer sealing ring of the static ring 2 is installed in the groove of the outer pressure cover; the dynamic ring assembly 2 includes a spring seat 2, several springs, a push ring 2, a gasket 2, an O-ring 2, a dynamic ring 2 and several transmission screws; the spring seat 2 is fixed to the outer circle of the shaft sleeve, and the spring seat 2 is provided with several stepped spring holes and several stepped through holes opposite to the spring holes, and the springs are installed in the spring holes of the spring seat 2 and abut against the inner side of the push ring 2, and the transmission screws pass through the stepped through holes of the spring seat 2 and are riveted to the inner through holes of the push ring 2; the outer side of the push ring 2 is provided with several inwardly protruding arc-shaped protrusions 2, and the inner side of the outer circle of the dynamic ring 2 is provided with several arc-shaped grooves 2, and the arc-shaped protrusions 2 of the push ring 2 match the arc-shaped grooves 2 of the dynamic ring 2; the inner groove of the dynamic ring 2 is equipped with a gasket 2 and an O-ring 2, and the gasket 2 is arranged on the outside of the O-ring 2.
3. The double-end face high pressure resistant mechanical seal according to claim 2, characterized in that: The depth of the inner groove of the first moving ring is greater than the depth of the inner groove of the second moving ring.
4. The double-end-face high-pressure resistant mechanical seal according to claim 1, characterized in that: The thickness of the washer 1 is greater than the compressible distance of the spring; the depth of the inner groove of the dynamic ring 1 is greater than the sum of the thickness of the washer 1 and the cross-sectional length of the O-ring 1 in the working state.