Mechanical seal device, fluid machine, and mechanical seal method

Abstract

The application provides a mechanical sealing device, a fluid mechanical equipment and a mechanical sealing method. The mechanical sealing device comprises a static ring, a sliding ring, a dynamic ring and a driving structure. The sliding ring is arranged inside or outside the static ring along the radial direction of the static ring. The sliding ring and the static ring are fixed along the circumferential direction of the static ring and can relatively move along the axial direction of the static ring. The hardness of the static ring and the sliding ring is different. The dynamic ring is arranged at one end of the static ring and the sliding ring along the axial direction. The driving structure is used to drive the sliding ring to move along the axial direction towards the dynamic ring, so that the sliding ring and the dynamic ring form a sealing surface, and a gap is formed between the static ring and the dynamic ring. When the driving force of the driving structure towards the dynamic ring of the static ring is removed, the static ring and the dynamic ring abut to form the sealing surface. The mechanical sealing device realizes the sealing effect through the sealing surface formed by the sliding ring and the dynamic ring or the sealing surface formed by the static ring and the dynamic ring, and can be applied in different fluid states, thereby prolonging the service life of the mechanical sealing device.

Description

Technical Field

[0001] This application relates to the field of mechanical seal technology, and in particular to a mechanical seal device, fluid machinery equipment, and mechanical seal method. Background Technology

[0002] In fluid machinery such as compressors, steam turbines, centrifugal pumps, and reactors, there is a shaft that penetrates the interior and exterior of the equipment's cavity. A circumferential gap exists between the shaft and the cavity, allowing the medium inside and outside the cavity to leak to both sides. A mechanical seal is used to connect the shaft and the cavity. The mechanical seal structure includes a rotating ring and a stationary ring fitted onto the shaft. The rotating and stationary rings rotate relative to each other to form a sealing surface, which keeps the cavity in a sealed state. However, the difference in hardness between the rotating and stationary rings affects the applicable scenarios of the mechanical seal. Once the hardness of the rotating and stationary rings in each mechanical seal is determined, it is difficult to change. When the fluid state inside the cavity changes, such as from a liquid to a gas-liquid mixture or from a liquid to a solid-liquid mixture, the hardness of the rotating and stationary rings cannot simultaneously adapt to the different fluid states within the cavity, leading to damage to the mechanical seal and affecting its sealing effect. Summary of the Invention

[0003] This application provides a mechanical seal device in which, by setting a sliding ring, the moving ring can form different sealing surfaces with sliding rings and stationary rings of different hardness, so as to achieve the purpose of making the mechanical seal device applicable in different situations.

[0004] In a first aspect, this application provides a mechanical seal device, comprising a stationary ring, a sliding ring, a rotating ring, and a drive structure. The stationary ring includes a first end face; the sliding ring includes a second end face, the sliding ring being disposed radially inside the stationary ring or sleeved on the outside of the stationary ring, the sliding ring and the stationary ring being fixed circumferentially along the stationary ring and capable of relative movement along the axial direction of the stationary ring, the stationary ring and the sliding ring having different hardnesses; the rotating ring being disposed axially at one end of the stationary ring and the sliding ring, the rotating ring elastically abutting against the first end face or the second end face along the axial direction; the drive structure is used to drive the second end face to move axially toward the rotating ring, so that the second end face and the rotating ring form a sealing surface, a gap is formed between the first end face and the rotating ring, and when the driving force of the drive structure on the second end face toward the rotating ring is released, the first end face and the rotating ring abut against each other to form a sealing surface.

[0005] In this embodiment, the axial direction of the stationary ring, the sliding ring, and the moving ring is a first direction. The end face of the stationary ring closest to the moving ring in the first direction is a first end face, and the end face of the sliding ring closest to the moving ring in the first direction is a second end face. In one embodiment, the stationary ring is fixed in the first direction, and the sliding ring is slidable along the first direction, so that the sliding ring and the stationary ring slide relative to each other in the first direction.

[0006] In this embodiment, the elastic contact refers to the rotating ring having an elastic force against the first end face or the second end face, causing the rotating ring to abut against the first end face or the second end face. In one embodiment, the mechanical seal device further includes an elastic element, which is coaxially arranged with the rotating ring along a first direction and located at the end of the rotating ring away from the stationary ring. The elastic element enables the rotating ring to elastically abut against the first end face or the second end face axially. In one embodiment, the elastic element is a spring. In another embodiment, the elastic element is a sheet spring or an elastic body.

[0007] In one embodiment, the mechanical seal device further includes a rotating ring support frame, which is coaxially arranged with the rotating ring. The elastic element, the rotating ring support frame, and the rotating ring are arranged along a first direction. The rotating ring support frame is fixedly connected to or abuts against the rotating ring, and is also fixedly connected to or abuts against the elastic element. The rotating ring support frame cooperates with the elastic element to make the rotating ring fit more tightly against the first end face or the second end face. The specific shape of the rotating ring support frame can be set according to the structure and size of the rotating ring and the elastic element. In one embodiment, the elastic element can be directly fixedly connected to or abuts against the rotating ring.

[0008] By configuring the sliding ring, the moving ring can form different sealing surfaces with the sliding ring and the stationary ring of different hardness. Different sealing surfaces are suitable for different fluid environments, enabling the mechanical seal device to adapt to different fluid environments, expanding the application range of the mechanical seal device, enhancing the sealing effect of the mechanical seal device, and extending the service life of the mechanical seal device.

[0009] In one possible implementation, the hardness of one of the stationary ring and the sliding ring is a first hardness, and the hardness of the other of the stationary ring and the sliding ring is a second hardness, wherein the first hardness is less than the second hardness, and the hardness of the moving ring is greater than or equal to the first hardness. In one embodiment, the hardness of the moving ring is less than the first hardness.

[0010] In one possible implementation, the stationary ring has the first hardness, and the sliding ring has the second hardness. In one embodiment, the moving ring has a harder hardness than the stationary ring. In one embodiment, the moving ring also has a harder hardness than the sliding ring. In one embodiment, the moving ring may have a harder hardness than the sliding ring but a harder hardness than the stationary ring. In one embodiment, the moving ring may have a harder hardness than the sliding ring and a harder hardness than the stationary ring. In one embodiment, the stationary ring 310 is made of graphite, and the sliding ring 320 is made of silicon carbide, where the hardness of graphite is less than that of silicon carbide.

[0011] When the fluid is a liquid, the fluid state includes a first state, a second state, and a third state. The first state is where the gas content in the fluid is greater than or equal to a first preset value, and the solid content in the fluid is less than a second preset value. The second state is where the solid content in the fluid is greater than or equal to the second preset value, and the gas content in the fluid is less than the first preset value. The third state is where the gas content in the fluid is less than the first preset value, and the solid content in the fluid is less than the second preset value. The first and second preset values ​​can be set based on the hardness or size of the sliding ring, the stationary ring, and the moving ring, or according to actual needs.

[0012] When the hardness of the sliding ring is greater than that of the stationary ring, and the fluid is in the second state, the driving structure drives the sliding ring to move toward the moving ring, so that the sliding ring and the moving ring are pressed together to form the second sealing surface, and a gap is formed between the moving ring and the first end face of the stationary ring. Since the hardness of the sliding ring is greater than that of the stationary ring, the materials constituting the second sealing surface all have greater hardness, and the mechanical seal device is not easily worn by solids, which can improve the service life of the mechanical seal device.

[0013] When the fluid is in the first state, the driving force of the driving structure on the sliding ring toward the moving ring is released. Under the action of the elastic element, the moving ring abuts against the stationary ring along the first direction and fits tightly against the stationary ring to form the first sealing surface. There is no additional driving force on the sliding ring toward the moving ring to make the second end face fit tightly against the moving ring. Since the hardness of the stationary ring is less than that of the sliding ring, the mechanical seal device is not prone to generating a lot of heat and burning out, thus improving the service life of the mechanical seal device.

[0014] When the fluid is in the third state, the first sealing surface formed by the moving ring and the stationary ring or the second sealing surface formed by the moving ring and the sliding ring can achieve a mechanical sealing effect.

[0015] In one possible implementation, the stationary ring has the second hardness, and the sliding ring has the first hardness. In one embodiment, the sliding ring is made of graphite, and the stationary ring is made of silicon carbide, wherein the hardness of graphite is less than that of silicon carbide.

[0016] In one embodiment, the materials of the sliding ring, the stationary ring, and the moving ring are selected from phenolic plastic, nylon, polytetrafluoroethylene, resin-impregnated graphite, rubber, ceramics, hard alloy weld overlay, tungsten carbide alloy, tin bronze, steel-bonded hard alloy, stainless steel, graphite, and silicon carbide. The hardness difference between the sliding ring, the stationary ring, and the moving ring can be adjusted according to the fluid or actual needs. For example, in one embodiment, the second hardness and the first hardness are based on the Mohs hardness standard, and the second hardness grade is at least one grade higher than the first hardness grade. In another embodiment, the second hardness and the first hardness are based on the Mohs hardness standard, and the second hardness grade is two grades higher than the first hardness grade. In one embodiment, the second hardness and the first hardness use the Rockwell A hardness scale (HRA), with the second hardness being 80HRA-90HRA and the first hardness being 55HRA-70HRA. In yet another embodiment, the second hardness and the first hardness use the Rockwell A hardness scale (HRA), and the second hardness value is at least 10HRA higher than the first hardness value. In one embodiment, the second hardness and the first hardness are based on the Rockwell hardness A scale (HRA), and the value of the second hardness is 20 HRA greater than the value of the first hardness.

[0017] In one embodiment, the mechanical seal device includes multiple sliding rings of different hardnesses. The driving structure can drive each sliding ring to move toward the rotating ring, so that each sliding ring can be pressed against the rotating ring to form a sealing surface. In another embodiment, the driving structure simultaneously drives at least two sliding rings to move toward the rotating ring, so that at least two sliding rings are simultaneously pressed against the rotating ring to form a sealing surface. The arrangement of multiple sliding rings can further expand the applicable scenarios and scope of use of the mechanical seal device.

[0018] In one possible implementation, the driving structure abuts against or is fixedly connected to the end of the sliding ring away from the moving ring. In one embodiment, the driving structure abuts against the sliding ring, and the method by which the driving structure releases the driving force of the sliding ring toward the moving ring includes moving the driving structure away from the moving ring. When the driving force of the driving structure on the sliding ring toward the moving ring is released, the elastic force of the elastic element on the moving ring pushes the sliding ring to move away from the moving ring until the moving ring abuts against the stationary ring. The moving ring can no longer move along the first direction, and the driving structure continues to move away from the moving ring until the moving ring and the sliding ring can no longer fit tightly together. At this time, the moving ring rotates relative to the stationary ring and elastically abuts against the first end face. The first end face of the stationary ring and the moving ring form a sealing surface, denoted as the first sealing surface. When the drive structure is released and the moving ring abuts against the stationary ring, the drive structure continues to move away from the moving ring along the first direction, so that the distance between the end face of the drive structure facing the sliding ring and the end face of the moving ring facing the sliding ring is greater than the length of the sliding ring in the first direction. The sliding ring can be located at any position between the drive structure and the sliding ring. At this time, even if the second end face of the sliding ring contacts the moving ring, since there is no additional force on the sliding ring towards the moving ring, the second end face and the moving ring cannot fit tightly to form an effective sealing surface. At this time, the mechanical seal device achieves sealing through the first sealing surface.

[0019] In one embodiment, the driving structure is fixedly connected to the sliding ring. When the driving force of the driving structure on the sliding ring toward the moving ring is released, the driving structure moves away from the moving ring along a first direction. The driving structure drives the sliding ring to move away from the moving ring, and the moving ring forms a gap with the second end face. This allows the mechanical seal device to respond faster to environmental changes and better adapt to changes in the fluid environment.

[0020] In one possible implementation, when the driving force of the driving structure on the second end face towards the moving ring is released, the first end face and the second end face are flush. If the first end face and the second end face are not flush, it complicates the process design, and the second end face needs to move an additional distance before it can contact the moving ring when the driving structure drives it to move, or the moving ring needs to move an additional distance when the elastic element makes it contact the first end face, increasing the wear of the mechanical seal device. However, having the first end face and the second end face flush reduces the difficulty of manufacturing and increases the working efficiency and reduces wear of the mechanical seal device. Furthermore, the end face of the moving ring near the stationary ring and the sliding ring is a plane, resulting in high precision in the contact between the moving ring and the first or second end face.

[0021] In one possible implementation, the stationary ring is fitted around the outer periphery of the sliding ring. The sliding ring needs to move away from or towards the moving ring in a first direction. Positioning the sliding ring inside the stationary ring, the size of the sliding ring can be relatively small, thereby reducing the friction between the sliding ring and the stationary ring. This allows the driving structure to more easily push the sliding ring to slide in the first direction.

[0022] In one possible implementation, the stationary ring is fitted onto the outer periphery of the sliding ring, and the mechanical seal device further includes a stationary ring support frame for fixing the stationary ring on the outer periphery of the stationary ring.

[0023] In one possible implementation, the stationary ring support frame includes a peripheral support portion and an end face support portion located at one end of the peripheral support portion. The peripheral support portion is used to fix the stationary ring on the outer peripheral side of the stationary ring. The end face support portion covers the end face of the stationary ring away from the moving ring, exposing at least a portion of the end face of the sliding ring away from the moving ring. The driving structure is located on the inner peripheral side of the end face support portion and abuts against or is fixedly connected to the end face of the sliding ring away from the moving ring to drive the sliding ring to move axially toward the moving ring.

[0024] In one embodiment, the end face of the sliding ring away from the moving ring is not covered by the end face support portion, and the driving structure abuts against or is fixedly connected to the end face of the sliding ring away from the moving ring. In another embodiment, a portion of the end face of the sliding ring away from the moving ring is covered by the end face support portion, exposing the portion of the end face of the sliding ring away from the moving ring, and the structure of the driving structure abuts against or is fixedly connected to the exposed end face of the sliding ring.

[0025] In one embodiment, the end face support portion has a through hole penetrating the end face support portion, exposing at least a portion of the end face of the sliding ring away from the rotating ring. The driving structure passes through the through hole and abuts against or is fixedly connected to the end face of the sliding ring away from the rotating ring. The outer periphery of the stationary ring and the end face away from the rotating ring are both covered by the stationary ring support frame, fixing the stationary ring in both radial and axial directions, enhancing its stability. The portion of the sliding ring's end face away from the rotating ring is covered by the end face support portion, and a gap exists between the portion of the sliding ring's end face away from the rotating ring and the end face support portion, limiting the sliding ring to between the rotating ring and the end face support portion, preventing the sliding ring from disengaging from the mechanical seal device in the first direction, thus reducing the sealing effect of the mechanical seal device and failing to achieve the purpose of multi-scenario applicability. In one embodiment, multiple through holes can be provided, allowing the driving structure to have sufficient driving force to drive the sliding ring to move.

[0026] In one possible implementation, the inner surface of the end face support is threadedly connected to the outer surface of the drive structure. The surface of the end face support that contacts the drive structure is threaded, and the surface of the drive structure that contacts the end face support is also threaded. The threads in the end face support and the threads in the drive structure engage with each other, allowing the drive structure to move in a first direction through rotation. The threaded connection between the end face support and the drive structure provides greater precision and controllability to the movement of the drive structure, improving the sealing effect of the mechanical seal device.

[0027] In one possible implementation, the sliding ring is fitted around the outer periphery of the stationary ring.

[0028] In one possible implementation, the mechanical seal device further includes a stationary ring support frame, which includes a circumferential support portion and an end face support portion located at one end of the circumferential support portion. The circumferential support portion is located on the outer circumference of the sliding ring, and the end face support portion is used to fix the stationary ring on the end face of the stationary ring away from the rotating ring. The end face support portion has a through hole that penetrates the end face support portion, exposing at least a portion of the end face of the sliding ring away from the rotating ring. The drive structure passes through the through hole and abuts against or is fixedly connected to the end face of the sliding ring away from the rotating ring to drive the sliding ring to move axially toward the rotating ring.

[0029] In one embodiment, the stationary ring is fixedly connected to the end face support portion, and the sliding ring is slidable relative to the circumferential support portion. In another embodiment, the end face support portion has multiple through holes, and the driving structure passes through these through holes to abut or be fixedly connected to the sliding ring, providing sufficient driving force to drive the sliding ring. In yet another embodiment, the outer surface of the driving structure in contact with the through holes is threaded, and the inner surface of the through holes in contact with the driving structure is threaded. The driving structure is threadedly connected to the through holes, providing higher precision and controllability in the movement of the driving structure. The sliding ring is positioned between the circumferential support portion and the stationary ring, and also between the end face support portion and the moving ring, improving the overall stability of the mechanical seal device and enhancing its sealing effect.

[0030] In one possible implementation, a first sealing ring is provided between the stationary ring and the sliding ring. The first sealing ring seals the gap between the stationary ring and the sliding ring, preventing fluid leakage from the gap. The first sealing ring enhances the sealing performance of the mechanical seal. The first sealing ring is an elastic sealing ring and can be a rubber ring.

[0031] In one embodiment, the sliding ring is sleeved on the outer periphery of the stationary ring, and a second sealing ring is provided between the sliding ring and the stationary ring support frame. The second sealing ring seals the gap between the sliding ring and the stationary ring support frame to prevent fluid from leaking from the gap between the sliding ring and the stationary ring support frame. The second sealing ring can enhance the sealing performance of the mechanical seal device.

[0032] In one embodiment, the stationary ring is sleeved on the outer periphery of the sliding ring, and a second sealing ring is provided between the stationary ring and the stationary ring support frame. The second sealing ring seals the gap between the stationary ring and the stationary ring support frame to prevent fluid from leaking from the gap between the stationary ring and the stationary ring support frame. The second sealing ring can enhance the sealing performance of the mechanical seal device.

[0033] In one possible implementation, the drive structure includes a drive motor and a sliding ring adjusting rod, the sliding ring adjusting rod being located at the end of the sliding ring away from the moving ring, and the drive motor being used to drive the sliding ring adjusting rod to move axially, thereby causing the sliding ring to move axially toward the moving ring.

[0034] In one embodiment, the extending direction of the sliding ring adjusting rod is a first direction, and the extending direction of the sliding ring adjusting rod is consistent with the axial direction of the sliding ring. The driving force of the sliding ring adjusting rod acts directly on the sliding ring, which can better drive the movement of the sliding ring. In another embodiment, the extending direction of the sliding ring adjusting rod is set at an angle to the axial direction of the sliding ring, which can reduce the size of the mechanical seal device in the first direction.

[0035] In one embodiment, the extending direction of the sliding ring adjusting rod is set at an angle to the axial direction of the sliding ring, wherein the angle is greater than 0° and less than or equal to 90°. The sliding ring is sleeved on the outer periphery of the stationary ring. The peripheral support portion is provided with the channel. The sliding ring adjusting rod is abutted or fixedly connected to the sliding ring through the channel. The sliding ring is limited between the end face support portion and the moving ring, and a gap is left between the end face support portion and the moving ring so that the sliding ring can move between the end face support portion and the moving ring. The sliding ring adjusting rod can drive the sliding ring to move along or away from the first direction within the channel.

[0036] In one embodiment, the extending direction of the sliding ring adjusting rod is set at an angle to the axial direction of the sliding ring, wherein the angle is greater than 0° and less than or equal to 90°. The stationary ring is sleeved on the outer periphery of the sliding ring. The peripheral support and the stationary ring are provided with the groove. The sliding ring adjusting rod abuts, engages, or is fixedly connected to the periphery of the sliding ring through the groove. The end support and the moving ring limit the sliding ring between the end support and the moving ring and leave a gap so that the sliding ring can move between the end support and the moving ring. The sliding ring adjusting rod can drive the sliding ring to move along or away from the first direction within the groove. The dimension of the groove along the first direction is greater than the dimension of the sliding ring adjusting rod along the first direction, so that the sliding ring adjusting rod can move along the first direction within the groove.

[0037] In one possible implementation, the sliding ring adjusting rod has a hollow structure and is coaxially arranged with the sliding ring. The inner diameter of the sliding ring adjusting rod is greater than or equal to the inner diameter of the sliding ring, and the outer diameter of the sliding ring adjusting rod is less than or equal to the outer diameter of the sliding ring.

[0038] In one embodiment, the stationary ring is sleeved on the outer periphery of the sliding ring, and the sliding ring adjusting rod is abutted or fixedly connected to the end face of the sliding ring away from the moving ring. The outer diameter of the sliding ring adjusting rod is less than or equal to the outer diameter of the sliding ring, so that the friction between the sliding ring adjusting rod and the stationary ring is reduced during the process of driving the sliding ring to move, thereby improving the efficiency of the drive motor and reducing energy loss.

[0039] In one embodiment, the outer diameter of the sliding ring adjusting rod is equal to the outer diameter of the sliding ring, and the inner diameter of the sliding ring adjusting rod is equal to the inner diameter of the sliding ring. The end face of the sliding ring away from the moving ring is covered by the sliding ring adjusting rod. The two ends of the sliding ring along the first direction are limited between the moving ring and the sliding ring adjusting rod. The contact area between the sliding ring adjusting rod and the sliding ring is large, or in other words, the force area between the sliding ring adjusting rod and the sliding ring is large, which is more conducive to driving the movement of the sliding ring.

[0040] In one embodiment, the sliding ring adjusting rod is a cylindrical structure. The sliding ring adjusting rod abuts against or is fixedly connected to the end face of the sliding ring away from the moving ring. The sliding ring adjusting rod is parallel to the first direction, and the diameter of the sliding ring adjusting rod is less than or equal to the difference between the outer diameter and the inner diameter of the sliding ring. This is to make it less likely for the sliding ring adjusting rod to be obstructed by the stationary ring and unable to continue moving during the process of driving the sliding ring to move. In order for the sliding ring adjusting rod to drive the sliding ring to move more effectively, multiple sliding ring adjusting rods can be provided.

[0041] In one embodiment, the sliding ring adjusting rod abuts, engages, or is fixedly connected to the circumference of the sliding ring, and the diameter of the sliding ring adjusting rod can be set according to actual needs to provide a more effective driving force.

[0042] In one possible implementation, the mechanical seal device further includes a detection device and a controller. The detection device is used to detect the fluid state, and the controller controls the drive structure to drive the second end face of the sliding ring to move axially toward the moving ring or to release the driving force on the second end face toward the moving ring based on the fluid state.

[0043] In one embodiment, the detection device is a refractometer, which distinguishes the fluid's state as a first state, a second state, or a third state by detecting the fluid's refractive index. This detected fluid state information is fed back to the controller, which then controls the movement of the drive structure after recognizing the information. In another embodiment, the detection device is a density analyzer, which distinguishes the fluid's state as a first state, a second state, or a third state by detecting the fluid's density. In other embodiments, the detection device can also be an infrared detection device, a sensor, etc., as long as it can detect the first state, the second state, or the third state of the liquid.

[0044] Secondly, this application provides a fluid machinery device, which includes a fluid cavity, a shaft, and a mechanical seal device as described in any one of the above. The fluid cavity is used to contain fluid, the shaft is installed in the fluid cavity and extends to the outside of the fluid cavity, the rotating ring, the stationary ring, and the sliding ring are sleeved on the shaft, the rotating ring is located in the fluid cavity, and the mechanical seal device achieves sealing between the inside and outside of the fluid cavity through the sealing surface.

[0045] The fluid machinery further includes a housing, with the fluid cavity located within the housing. The shaft is mounted within the fluid cavity and extends through the housing to the outside of the fluid cavity. In one embodiment, one end of the shaft extends through the housing to the outside of the housing, while the other end of the shaft is located within the fluid cavity. In another embodiment, both ends of the shaft extend through the housing to the outside of the housing, resulting in two junctions between the shaft and the housing. A mechanical seal is provided at each of these two junctions.

[0046] The mechanical seal is located at the junction of the shaft and the housing, and is used to isolate the fluid cavity from the external environment. The cross-section of the housing can be circular, elliptical, polygonal, etc., and the specific shape of the housing is set according to the actual use scenario.

[0047] The mechanical seal device achieves a seal between the inside and outside of the fluid cavity of the fluid machinery. On the one hand, the mechanical seal device prevents fluid in the fluid cavity from leaking out through the junction of the shaft and the housing, thus preventing fluid loss and damage to external components. On the other hand, the mechanical seal device prevents air and liquid outside the housing from entering the fluid cavity, contaminating the fluid inside or damaging the equipment inside. Furthermore, during use, the fluid state in the fluid cavity may vary; for example, the fluid may contain solid impurities or air bubbles. The mechanical seal device can use either the sealing surface formed by the sliding ring and the moving ring or the sealing surface formed by the stationary ring and the moving ring to achieve a seal between the inside and outside of the fluid cavity, thereby extending the service life of the mechanical seal device.

[0048] In one embodiment, the moving ring, the stationary ring, and the sliding ring are sleeved on the shaft. The moving ring is located inside the fluid cavity. The moving ring is fixed on the shaft and can rotate with the shaft. The stationary ring and the sliding ring do not rotate with the shaft. When the shaft rotates, the shaft rotation drives the moving ring to rotate, and the moving ring rotates relative to the stationary ring and the sliding ring.

[0049] In one embodiment, the elastic element and the moving ring support are sleeved on the shaft. In another embodiment, the sliding ring adjusting rod is disposed on the outer periphery of the shaft, or the sliding ring adjusting rod is sleeved on the shaft.

[0050] In one possible implementation, the fluid machinery further includes an impeller and a motor. The impeller is located inside the fluid cavity and is fixedly connected to the shaft. The motor is located outside the fluid cavity and is connected to the shaft. The motor is used to drive the shaft to rotate, and the rotation of the shaft drives the impeller to rotate.

[0051] In one possible implementation, the fluid machinery is a pump, centrifuge, reactor, or compressor.

[0052] When the mechanical seal is applied to the pump, the fluid in the fluid chamber is water. The impeller rotation drives the water into and out of the fluid chamber. The fluid chamber includes an inlet and an outlet. Water enters the fluid chamber from the inlet along a first direction and exits from the outlet along a second direction perpendicular to the first direction. The stationary ring is fitted around the outer periphery of the sliding ring and is fixedly connected to the inner surface of the housing.

[0053] In one embodiment, the fluid machinery is the pump, and the detection device is located on the inlet side of the pump for detecting the fluid state entering the fluid chamber from the inlet. In another embodiment, the detection device is located on the outlet side of the pump for detecting the fluid state flowing out of the fluid chamber from the outlet.

[0054] The pump, through the setting of the sliding ring, allows the mechanical seal device to form different sealing surfaces to adapt to different water conditions, preventing water from leaking from the junction of the shaft and the housing to the outside of the fluid cavity. On the one hand, this avoids reducing the working efficiency of the pump; on the other hand, it prevents leaked water from flowing to the motor, causing damage and corrosion to the motor; furthermore, it can extend the service life of the mechanical seal device and ensure the sealing reliability of the pump.

[0055] Thirdly, this application provides a mechanical sealing method applied to the fluid machinery equipment described in any of the preceding claims, the mechanical sealing method comprising:

[0056] Obtain the fluid state within the fluid cavity;

[0057] According to the fluid state, the drive structure is controlled to drive the second end face of the sliding ring to move axially toward the moving ring or to release the driving force on the second end face toward the moving ring.

[0058] In one possible implementation, when the hardness of the sliding ring is a first hardness and the hardness of the stationary ring is a second hardness, controlling the driving structure according to the fluid state to drive the second end face of the sliding ring to move axially toward the moving ring or to release the driving force on the second end face toward the moving ring includes:

[0059] Determine whether the fluid state is the first state, wherein the first state is that the gas content in the fluid is greater than or equal to a first preset value, and the solid content in the fluid is less than a second preset value;

[0060] When the fluid state is the first state, the drive structure is controlled to drive the second end face of the sliding ring to move axially toward the moving ring, so that the second end face and the moving ring form a sealing surface, and a gap is formed between the first end face and the moving ring.

[0061] In one embodiment, controlling the driving structure to move the second end face of the sliding ring axially toward the moving ring or releasing the driving force on the second end face toward the moving ring according to the fluid state further includes:

[0062] When the fluid state is not the first state, determine whether the fluid state is the second state;

[0063] When the fluid state is the second state, the drive structure is controlled to release the driving force on the second end face towards the rotating ring, so that the first end face and the rotating ring form a sealing surface. A mechanical seal is achieved through the sealing surface formed by the first end face and the rotating ring.

[0064] The drive structure does not work when the fluid state is neither the first state nor the second state.

[0065] In one possible implementation, when the sliding ring has a second hardness and the stationary ring has a first hardness, controlling the driving structure to move the second end face of the sliding ring axially toward the moving ring or releasing the driving force on the second end face toward the moving ring according to the fluid state includes:

[0066] Determine whether the fluid state is the first state;

[0067] When the fluid state is the first state, the drive structure is controlled to release the driving force on the second end face toward the moving ring, so that the first end face and the moving ring form a sealing surface.

[0068] In one embodiment, controlling the driving structure to move the second end face of the sliding ring axially toward the moving ring or releasing the driving force on the second end face toward the moving ring according to the fluid state further includes:

[0069] When the fluid state is not the first state, determine whether the fluid state is the second state;

[0070] When the fluid state is the second state, the drive structure drives the second end face of the sliding ring to move axially toward the moving ring so that the second end face and the moving ring form a sealing surface, and a gap is formed between the first end face and the moving ring;

[0071] When the fluid state is neither the first state nor the second state, the fluid state is the third state, and the drive structure is not working. The drive structure not working means that the drive structure maintains its original state and does not operate further.

[0072] In this application, by setting the sliding ring, the moving ring can form different sealing surfaces with sliding rings and stationary rings of different hardness. Different sealing surfaces are suitable for different fluid environments, so that the mechanical seal device can adapt to different fluid environments, expand the application range of the mechanical seal device, enhance the sealing effect of the mechanical seal device, and improve the efficiency and safety performance of fluid machinery equipment. Attached Figure Description

[0073] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.

[0074] Figure 1 This is a schematic diagram of the structure of a fluid machinery device provided in one embodiment of this application;

[0075] Figure 2 This is a schematic diagram of the structure of a fluid machinery device provided in one embodiment of this application;

[0076] Figure 3 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0077] Figure 4 This is a partial cross-sectional view of a fluid machinery device provided in one embodiment of this application;

[0078] Figure 5 This is a partial cross-sectional view of a fluid machinery device provided in one embodiment of this application;

[0079] Figure 6 This is a partial cross-sectional view of a fluid machinery device provided in one embodiment of this application;

[0080] Figure 7 This is a schematic diagram of the pump provided in one embodiment of this application;

[0081] Figure 8 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0082] Figure 9 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0083] Figure 10 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0084] Figure 11 yes Figure 3 A magnified view of part M in the middle;

[0085] Figure 12 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0086] Figure 13 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0087] Figure 14 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0088] Figure 15 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0089] Figure 16 This is a cross-sectional view of the mechanical seal device provided in one embodiment of this application;

[0090] Figure 17 This is a flowchart of a mechanical sealing method provided in one embodiment of this application;

[0091] Figure 18 This is a flowchart of a mechanical sealing method provided in one embodiment of this application;

[0092] Figure 19 This is a flowchart of a mechanical sealing method provided in one embodiment of this application. Detailed Implementation

[0093] The technical solutions of the embodiments of this application will be described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0094] In this document, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0095] Furthermore, in this article, directional terms such as "upper" and "lower" are defined relative to the orientation of the structure as shown in the attached drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and can change accordingly depending on the orientation of the structure.

[0096] This application provides a mechanical seal device, which includes a stationary ring, a sliding ring, a rotating ring, and a drive structure. The sliding ring is disposed radially inside the stationary ring or sleeved on the outside of the stationary ring. The sliding ring and the stationary ring are fixed circumferentially to the stationary ring and can move relative to each other axially. The stationary ring and the sliding ring have different hardnesses. The rotating ring is axially disposed at the same end of the stationary ring and the sliding ring. The drive structure drives the sliding ring to move axially toward the rotating ring, so that the sliding ring and the rotating ring form a sealing surface, and a gap is formed between the stationary ring and the rotating ring. When the driving force of the drive structure on the stationary ring toward the rotating ring is released, the stationary ring and the rotating ring abut against each other to form a sealing surface. The mechanical seal device achieves a sealing effect through the sealing surface formed by the sliding ring and the rotating ring or the sealing surface formed by the stationary ring and the rotating ring, and can be applied in different fluid states, extending the service life of the mechanical seal device.

[0097] Please see Figure 1 This application provides a fluid machinery device 10, which includes a fluid cavity 100, a shaft 200, and a mechanical seal 300. The fluid cavity 100 is used to contain a fluid F, and the shaft 200 is installed inside the fluid cavity 100 and extends outside the fluid cavity 100. The fluid machinery device 10 also includes a housing 101, with the fluid cavity 100 located within the internal space of the housing 101. The shaft 200 is installed inside the fluid cavity 100 and extends through the housing 101 to the outside of the fluid cavity 100. In this embodiment, one end of the shaft 200 extends through the housing 101 to the outside of the housing (e.g., ...). Figure 1 As shown), the other end of shaft 200 is located inside fluid cavity 100. In one embodiment, both ends of shaft 200 extend through housing 101 to the outside of housing (e.g., Figure 2 As shown in the figure, there are two junctions between the shaft 200 and the housing 101, and mechanical seal devices 300 are provided at both junctions between the shaft 200 and the housing 101.

[0098] The mechanical seal device 300 is located at the junction of the shaft 200 and the housing 101, and is used to isolate the internal and external environments of the fluid cavity 100. The cross-section of the housing 101 can be circular, elliptical, polygonal, etc., and the specific shape of the housing 101 is set according to the actual use scenario.

[0099] In this embodiment, the rotating ring, stationary ring, and sliding ring of the mechanical seal device 300 are sleeved on the shaft 200, and the rotating ring is located inside the fluid cavity 100. The mechanical seal device 300 achieves the sealing between the inside and outside of the fluid cavity 100 through the sealing surface formed by the sliding ring and the rotating ring or the sealing surface formed by the stationary ring and the rotating ring.

[0100] In this application, a mechanical seal device 300 is used to seal the fluid cavity 100 inside and outside the fluid machinery device 10. On the one hand, the mechanical seal device 300 can prevent the fluid F inside the fluid cavity 100 from leaking to the outside of the fluid cavity 100 through the junction of the shaft 200 and the housing 101, thus preventing the loss of fluid F and damage to external components. On the other hand, the mechanical seal device 300 can prevent air and liquid outside the housing 101 from entering the fluid cavity 100, contaminating the fluid F inside the fluid cavity 100, or damaging the equipment inside the fluid cavity 100. Furthermore, in combination with... Figure 3 As shown, when the fluid machinery device 10 is in use, the fluid state inside the fluid cavity 100 will be different. For example, the fluid F may contain solid impurities or air bubbles. The mechanical seal device 300 can use the sealing surface formed by the sliding ring 320 and the moving ring 330 or the sealing surface formed by the stationary ring 310 and the moving ring 330 to achieve a seal between the inside and outside of the fluid cavity 100 according to the different fluid states, so as to extend the service life of the mechanical seal device 300.

[0101] In one possible implementation, the fluid machinery device 10 further includes an impeller 110 and a motor 210 (e.g., Figure 1 As shown, the impeller 110 is located inside the fluid cavity 100 and is fixedly connected to the shaft 200. The motor 210 is located outside the fluid cavity 100 and is connected to the shaft 200. The motor 210 drives the shaft 200 to rotate, and the rotation of the shaft 200 drives the impeller 110 to rotate. The structures of the impeller 110 and the motor 210 are not limited to... Figure 1 The structure shown can be customized according to actual needs.

[0102] In one possible implementation, the fluid machinery 10 is a pump 11 (e.g., Figure 7 (as shown), one of a centrifuge, a reaction vessel, or a compressor.

[0103] The mechanical seal device 300 of this application is described in detail below.

[0104] Please see Figure 3This application provides a mechanical seal device 300, including a stationary ring 310, a sliding ring 320, a rotating ring 330, and a drive structure 340. The stationary ring 310 and the rotating ring 330 are sleeved on a shaft 200 and arranged axially. The stationary ring 310 is rotatable relative to the shaft 200; that is, when the shaft 200 rotates, the stationary ring 310 remains stationary. The rotating ring 330 is fixed circumferentially to the shaft 200, meaning that the rotation of the shaft 200 can drive the rotating ring 330 to rotate synchronously. When the shaft 200 rotates, the rotating ring 330 follows the rotation of the shaft 200.

[0105] The stationary ring 310 includes a first end face 311, and the sliding ring 320 includes a second end face 321. The sliding ring 320 is disposed inside or sleeved on the outside of the stationary ring 310 along the radial direction R of the stationary ring 310. The sliding ring 320 and the stationary ring 310 are fixed circumferentially along the stationary ring 310 and can move relative to each other along the axial direction of the stationary ring 310. The stationary ring 310 and the sliding ring 320 have different hardnesses. Specifically, one of the stationary ring 310 and the sliding ring 320 has a first hardness, and the other has a second hardness, where the first hardness is less than the second hardness.

[0106] In this embodiment, the sliding ring 320 is sleeved on the outer side of the stationary ring 310 along the radial direction R, meaning the sliding ring 320 is sleeved on the outer circumference of the stationary ring 310. The sliding ring 320 is sleeved on the inner side of the stationary ring 310 along the radial direction R, meaning the stationary ring 310 is sleeved on the outer circumference of the sliding ring 320. The outer circumference of the stationary ring 310 refers to the side of the stationary ring 310 away from the outer circumferential surface of the shaft 200, and the outer circumferential side of the sliding ring 320 refers to the side of the sliding ring 320 away from the outer circumferential surface of the shaft 200. In this embodiment, the stationary ring 310 is sleeved on the outer circumference of the sliding ring 320. The axial direction of the stationary ring 310, sliding ring 320, and moving ring 330 is the first direction X (e.g., ...). Figure 3 As shown, the end face of the stationary ring 310 closest to the moving ring 330 in the first direction X is the first end face 311, and the end face of the sliding ring 320 closest to the moving ring 330 in the first direction X is the second end face 321. The sliding ring 320 and the stationary ring 310 are fixed circumferentially and can move relative to each other axially, indicating that the sliding ring 320 and the stationary ring 310 remain relatively fixed in the circumferential direction, but can slide relative to each other in the axial direction (first direction X). In this embodiment, the stationary ring 310 remains axially fixed to the shaft 200, and the sliding ring 320 slides axially relative to the shaft 200, so that the sliding ring 320 and the stationary ring 310 slide relative to each other axially.

[0107] A rotating ring 330 is disposed axially (in the first direction X) at one end of the stationary ring 310 and the sliding ring 320, and the rotating ring 330 elastically abuts against the first end face 311 or the second end face 321 along the axial direction. In this embodiment, the hardness of the rotating ring 330 is greater than or equal to a first hardness. In some embodiments, the hardness of the rotating ring 330 is less than the first hardness.

[0108] In this embodiment, the elastic contact refers to the rotating ring 330 having an elastic force against the first end face 311 or the second end face 321, causing the rotating ring 330 to abut against the first end face 311 or the second end face 321. In one embodiment, the mechanical seal device 300 further includes an elastic element 331, which is sleeved on the shaft 200 and located at the end of the rotating ring 330 away from the stationary ring 310. The elastic element 331 enables the rotating ring 330 to elastically abut against the first end face 311 or the second end face 321 along the axial direction. The elastic force of the elastic element 331 acts on the rotating ring 330 along the first direction X, causing the rotating ring 330 to tightly fit against the first end face 311 or the second end face 321 to form a sealing surface. In this embodiment, the elastic element 331 is a spring. In another embodiment, the elastic element 331 is a spring sheet or an elastic body.

[0109] Please continue reading. Figure 3 In one embodiment, the mechanical seal device 300 further includes a rotating ring support frame 332, which is sleeved on the shaft 200. The elastic element 331, the rotating ring support frame 332, and the rotating ring 330 are arranged along a first direction X. The rotating ring support frame 332 is fixedly connected to or abuts against the rotating ring 330, and is also fixedly connected to or abuts against the elastic element 331. The rotating ring support frame 332 cooperates with the elastic element 331 to make the rotating ring 330 fit more tightly against the first end face 311 or the second end face 321. The specific shape of the rotating ring support frame 332 can be set according to the structure and size of the rotating ring 330 and the elastic element 331. In some embodiments, the elastic element 331 can be directly fixedly connected to or abuts against the rotating ring 330. The term "abutting" refers to the contact between two components and the interaction between them. For example, when the elastic element 331 abuts against the moving ring 330, it means that the elastic element 331 is in contact with the moving ring 330, and the elastic element 331 has an elastic force on the moving ring 330, while the moving ring 330 has a reaction force on the elastic element 331.

[0110] Drive structure 340 is used to drive the second end face 321 to move axially (in the first direction X) toward the moving ring 330 (e.g. Figure 3 As shown), so that the second end face 321 and the moving ring 330 form a sealing surface, and a gap is formed between the first end face 311 and the moving ring 330. When the driving force of the driving structure 340 on the second end face 321 toward the moving ring 330 is released, the first end face 311 and the moving ring 330 abut against each other to form a sealing surface.

[0111] In this embodiment, the moving ring 330, the stationary ring 310, and the sliding ring 320 are sleeved on the shaft 200 (e.g., Figure 3 As shown, the moving ring 330 is located inside the fluid cavity 100. The moving ring 330 is fixed on the shaft 200 and can rotate with the shaft 200. The stationary ring 310 and the sliding ring 320 do not rotate with the shaft 200. When the shaft 200 rotates, the rotation of the shaft 200 drives the moving ring 330 to rotate. The moving ring 330 rotates relative to the stationary ring 310 and the sliding ring 320.

[0112] Please see Figure 4 The driving structure 340 abuts against or is fixedly connected to at least a portion of the sliding ring 320. The driving structure 340 drives the sliding ring 320 to move toward the moving ring 330, causing the sliding ring 320 to abut against the moving ring 330. The stationary ring 310 is fixed in position in the first direction X. The driving structure 340 continues to drive the sliding ring 320 toward the moving ring 330, pushing the moving ring 330 away from the stationary ring 310. The moving ring 330 and the stationary ring 310 are in a state of disengagement, with a gap between them. At this time, the moving ring 330 rotates relative to the sliding ring 320 and elastically abuts only against the second end face 321. The second end face 321 and the moving ring 330 form a sealing surface, denoted as the second sealing surface 302. At this time, the mechanical seal device 300 achieves sealing inside and outside the fluid cavity 100 through the second sealing surface 302.

[0113] Please see Figure 5 In this embodiment, the driving structure 340 abuts against the sliding ring 320. The method by which the driving structure 340 releases the driving force of the sliding ring 320 towards the moving ring 330 includes moving the driving structure 340 away from the moving ring 330. When the driving force of the driving structure 340 on the sliding ring 320 towards the moving ring 330 is released, the elastic force of the elastic member 331 on the moving ring 330 pushes the sliding ring 320 away from the moving ring 330 until the moving ring 330 abuts against the stationary ring 310. The moving ring 330 can no longer move along the first direction X. The driving structure 340 continues to move away from the moving ring 330 until the moving ring 330 and the sliding ring 320 can no longer be tightly fitted (e.g., ...). Figure 5 As shown), at this time, the moving ring 330 rotates relative to the stationary ring 310 and elastically abuts against the first end face 311. The first end face 311 of the stationary ring 310 and the moving ring 330 form a sealing surface, denoted as the first sealing surface 301 (as shown). Figure 5(As shown). In this embodiment, when the drive structure 340 is released and the moving ring 330 abuts against the stationary ring 310, the drive structure 340 continues to move away from the moving ring 330 along the first direction X, so that the distance between the end face of the drive structure 340 facing the sliding ring 320 and the end face of the moving ring 330 facing the sliding ring 320 is greater than the length of the sliding ring 320 in the first direction X. The sliding ring 320 can be located at any position between the drive structure 340 and the sliding ring 320. At this time, even if the second end face 321 of the sliding ring 320 contacts the moving ring 330, since there is no additional force on the sliding ring 320 towards the moving ring 330, the second end face 321 and the moving ring 330 cannot be tightly fitted to form an effective sealing surface. At this time, the mechanical seal device 300 achieves sealing inside and outside the fluid cavity 100 through the first sealing surface 301.

[0114] In one embodiment, the drive structure 340 is fixedly connected to the sliding ring 320 (e.g., Figure 6 (As shown). When the driving force of the driving structure 340 on the sliding ring 320 toward the moving ring 330 is released, the driving structure 340 moves away from the moving ring 330 along the first direction X. The driving structure 340 drives the sliding ring 320 to move away from the moving ring 330, so that the moving ring 330 and the second end face 321 form a gap.

[0115] The different hardnesses of the stationary ring 310, sliding ring 320, and rotating ring 330 will affect the applicable scenarios of the mechanical seal device 300. The different hardnesses of the stationary ring 310 and the sliding ring 320 allow the first sealing surface 301 formed by the rotating ring 330 and the stationary ring 310 and the second sealing surface 302 formed by the rotating ring 330 and the sliding ring 320 to be applicable to different scenarios.

[0116] The fluid can be a liquid or a flowable slurry or melt. Liquids include water, organic solvents, and mixed organic solvents. When the fluid F is a liquid, the mechanical seal effect can be achieved by forming a sealing surface between the moving ring 330 and the stationary ring 310 or the sliding ring 320.

[0117] When solid particles are mixed into fluid F, the harder the material constituting the sealing surface, the less likely it is to be worn by the solid particles. If the less hard one of the stationary ring 310 and the sliding ring 320 is used with the rotating ring 330, the hard solid particles can easily damage the less hard one of the stationary ring 310 and the sliding ring 320, leading to a decrease in sealing performance or even loss of sealing effect. In this case, the more hard one of the stationary ring 310 and the sliding ring 320 should be used with the rotating ring 330. In this embodiment, the hardness of the rotating ring 330 is greater than or equal to... Regarding the first hardness, the harder of the stationary ring 310 and the sliding ring 320, along with the harder of the rotating ring 330, are both relatively high. When hard solid particles enter the sealing surface, they will not damage the sealing surface, thus extending the service life of the sealing surface. In one embodiment, when the hardness of the rotating ring 330 is less than the first hardness, the harder of the stationary ring 310 and the sliding ring 320 is used in conjunction with the rotating ring 330. Compared to the case where the less hard of the stationary ring 310 and the sliding ring 320 is used in conjunction with the rotating ring 330, the sealing surface is less damaged, and the service life of the sealing surface can be extended.

[0118] When gas is present in fluid F, the greater the hardness of the material constituting the sealing surface, the greater the heat generated during rotary sealing. If the harder of the stationary ring 310 and the sliding ring 320 is used in conjunction with the rotating ring 330, in this embodiment, the hardness of the rotating ring 330 is greater than or equal to the first hardness. The friction between the rotating ring 330 and the harder of the stationary ring 310 and the sliding ring 320 generates a large amount of heat, which is not easily dissipated, causing the mechanical seal device 300 to be easily burned out. In this case, using the less hard of the stationary ring 310 and the sliding ring 320 in conjunction with the rotating ring 330 results in less heat generation from friction between the sealing surfaces, reducing the risk of burning out the sealing surfaces and extending the service life of the mechanical seal device 300. In another embodiment, when the hardness of the rotating ring 330 is less than the first hardness, using the less hard of the stationary ring 310 and the sliding ring 320 in conjunction with the rotating ring 330 results in less heat generation from friction between the sealing surfaces compared to using the harder of the stationary ring 310 and the sliding ring 320 in conjunction with the rotating ring 330, thus extending the service life of the sealing surfaces.

[0119] In one embodiment, the mechanical seal device 300 uses only the stationary ring 310 and the rotating ring 330 to form a sealing surface to achieve a sealing effect. The sealing surface formed by the stationary ring 310 and the rotating ring 330 cannot adapt to various fluid states. When the properties of the fluid F in the fluid cavity 100 change, if the hardness of the stationary ring 310 or the rotating ring 330 does not change, the mechanical seal device 300 is easily damaged. If the stationary ring 310 or the rotating ring 330 is replaced to adapt to the environment of the fluid F, the mechanical seal device 300 needs to be disassembled and reassembled, which makes it inconvenient to use or impossible to achieve at all.

[0120] In this application, the sliding ring 320 is set (e.g. Figures 3 to 6 As shown, the moving ring 330 can form a second sealing surface 302 and a first sealing surface 301 with the sliding ring 320 and the stationary ring 310 of different hardness, respectively. The first sealing surface 301 and the second sealing surface 302 are suitable for different fluid F environments, so that the mechanical seal device 300 can adapt to different fluid F environments, expand the application range of the mechanical seal device 300, enhance the sealing effect of the mechanical seal device 300, and improve the efficiency and safety performance of the fluid machinery equipment 10.

[0121] In one possible implementation, the stationary ring 310 has a first hardness, and the sliding ring 320 has a second hardness. That is, the hardness of the stationary ring 310 is less than the hardness of the sliding ring 320, and the hardness of the moving ring 330 is greater than the hardness of the stationary ring 310. In one embodiment, the hardness of the moving ring 330 is also greater than the hardness of the sliding ring 320. In one embodiment, the hardness of the moving ring 330 may be less than the hardness of the sliding ring 320 and greater than the hardness of the stationary ring 310. In one embodiment, the hardness of the moving ring 330 may be less than the hardness of the sliding ring 320 and less than the hardness of the stationary ring 310.

[0122] In one embodiment, the stationary ring 310 is made of graphite, and the sliding ring 320 is made of silicon carbide. The hardness of graphite is less than that of silicon carbide.

[0123] In one embodiment, the sliding ring 320, stationary ring 310, and moving ring 330 are made of materials selected from phenolic plastic, nylon, polytetrafluoroethylene, resin-impregnated graphite, rubber, ceramics, hard alloy overlay, tungsten carbide alloy, tin bronze, steel-bonded hard alloy, stainless steel, graphite, and silicon carbide. The hardness of the stationary ring 310 is less than that of the sliding ring 320 and the moving ring 330. The hardness difference between the sliding ring 320, stationary ring 310, and moving ring 330 can be adjusted according to the fluid in the fluid cavity 100 or actual needs. For example, in one embodiment, the second hardness and the first hardness are based on the Mohs hardness standard, with the second hardness grade being at least one grade higher than the first hardness grade. In another embodiment, the second hardness and the first hardness are based on the Mohs hardness standard, with the second hardness grade being two grades higher than the first hardness grade. In yet another embodiment, the second hardness and the first hardness use the Rockwell A hardness scale (HRA), with the second hardness being 80HRA-90HRA and the first hardness being 55HRA-70HRA. In one embodiment, the second hardness and the first hardness are based on the Rockwell A hardness scale (HRA), and the value of the second hardness is at least 10 HRA greater than the value of the first hardness. In another embodiment, the second hardness and the first hardness are based on the Rockwell A hardness scale (HRA), and the value of the second hardness is 20 HRA greater than the value of the first hardness.

[0124] When fluid F is a liquid, the fluid state includes a first state, a second state, and a third state. The first state is where the gas content in the fluid is greater than or equal to a first preset value, and the solid content in the fluid is less than a second preset value. The second state is where the solid content in the fluid is greater than or equal to the second preset value, and the gas content in the fluid is less than the first preset value. The third state is where the gas content in the fluid is less than the first preset value, and the solid content in the fluid is less than the second preset value. The first and second preset values ​​can be set based on the hardness or size of the sliding ring 320, the stationary ring 310, and the moving ring 330, or according to actual needs.

[0125] In this embodiment, the hardness of the sliding ring 320 is greater than that of the stationary ring 310, and the hardness of the moving ring 330 is greater than that of the stationary ring 310. This embodiment uses a pump 11 as an example of a fluid machinery device 10 to illustrate the working process of the mechanical seal device 300 in the pump 11. When the mechanical seal device 300 is applied to the pump 11 (e.g.) Figure 7 As shown), the fluid F in the fluid cavity 100 is water. The impeller 110 rotates, causing the water to enter and exit the fluid cavity 100. The fluid cavity 100 includes an inlet 102 and an outlet 103. Water enters the fluid cavity 100 from the inlet 102 along a first direction X and exits from the outlet 103 along a second direction Y to the outside of the fluid cavity 100. The second direction Y is perpendicular to the first direction X. A stationary ring 310 is fitted around the outer periphery of the sliding ring 320 (e.g., ...). Figure 3 As shown), the stationary ring 310 is fixedly connected to the inner surface of the housing 101.

[0126] When pump 11 is working, the water entering fluid chamber 100 includes the first, second, and third states described above. When the fluid state is the second state, that is, when more solid particles are mixed in the water, the drive structure 340 drives the sliding ring 320 to move towards the moving ring 330, so that the sliding ring 320 and the moving ring 330 are tightly pressed together to form the second sealing surface 302 (e.g., Figure 4 As shown in the figure, the first end face 311 of the moving ring 330 and the stationary ring 310 form a gap, and the second sealing surface 302 formed by the moving ring 330 and the second end face 321 seals the fluid cavity 100. Since the hardness of the sliding ring 320 is greater than that of the stationary ring 310, the materials constituting the second sealing surface 302 are all relatively hard, and the mechanical seal device 300 is not easily worn by solids, which can improve the service life of the mechanical seal device 300.

[0127] When the fluid state is the first state, i.e., there is a lot of gas in the water, the driving force of the driving structure 340 on the sliding ring 320 in the direction of the moving ring 330 is released (e.g., Figure 5As shown, under the action of the elastic element 331, the moving ring 330 abuts against the stationary ring 310 along the first direction and fits tightly against the stationary ring 310 to form the first sealing surface 301. There is no additional driving force on the sliding ring 320 towards the moving ring 330, so the second end face 321 fits tightly against the moving ring 330. At this time, the second end face 321 contacts the moving ring 330 to form a gap. The first sealing surface 301 formed by the moving ring 330 and the first end face 311 plays a sealing role in the mechanical seal device 300. Since the hardness of the stationary ring 310 is less than that of the sliding ring 320, the mechanical seal device 300 is not easy to generate a lot of heat and burn out, thus improving the service life of the mechanical seal device 300.

[0128] When the fluid is in the third state, that is, when there are few or no bubbles or solid particles in the water, the first sealing surface 301 formed by the moving ring 330 and the stationary ring 310 or the second sealing surface 302 formed by the moving ring 330 and the sliding ring 320 can achieve the mechanical sealing effect.

[0129] In other words, in this embodiment, the pump 11, through the setting of the sliding ring 320, allows the mechanical seal device 300 to form different sealing surfaces to adapt to different water conditions, preventing water from leaking from the junction of the shaft 200 and the housing 101 to the outside of the fluid cavity 100. On the one hand, this avoids reducing the working efficiency of the pump 11, and on the other hand, it prevents leaked water from flowing to the motor 210, causing damage and corrosion to the motor 210. Furthermore, it can also extend the service life of the mechanical seal device 300 and ensure the sealing reliability of the pump 11.

[0130] It should be noted that, Figure 7 Pump 11 in this application is merely an example and does not limit the configuration of pump 11. Pump 11 in this application may also have other structures.

[0131] In one possible implementation, the stationary ring 310 has a second hardness, and the sliding ring 320 has a first hardness, meaning the hardness of the stationary ring 310 is greater than that of the sliding ring 320. In one embodiment, the moving ring 330 has a harder hardness than the sliding ring 320. In another embodiment, the moving ring 330 has a harder hardness than the stationary ring 310. In yet another embodiment, the moving ring 330 may have a harder hardness than the stationary ring 310, but a harder hardness than the sliding ring 320.

[0132] In one embodiment, the sliding ring 320 is made of graphite, and the stationary ring 310 is made of silicon carbide, with graphite having a lower hardness than silicon carbide. In another embodiment, the sliding ring 320, stationary ring 310, and moving ring 330 are made of materials selected from phenolic plastics, nylon, polytetrafluoroethylene, resin-impregnated graphite, rubber, ceramics, hard alloy weld overlay, tungsten carbide alloy, tin bronze, steel-bonded hard alloy, stainless steel, graphite, and silicon carbide, and the hardness of the sliding ring 320 is less than that of the stationary ring 310 and the moving ring 330. The hardness difference between the sliding ring 320, stationary ring 310, and moving ring 330 can be adjusted according to actual needs.

[0133] In this embodiment, the hardness of the stationary ring 310 is greater than that of the sliding ring 320, and the hardness of the rotating ring 330 is greater than that of the stationary ring 310. When the fluid F is in the third state, the rotating ring 330 can achieve a mechanical seal effect by forming a sealing surface with either the stationary ring 310 or the sliding ring 320. When the fluid F is in the first state, i.e., the fluid F contains a large number of air bubbles, the driving structure 340 drives the sliding ring 320, which has a lower hardness, to move towards the rotating ring 330, so that the sliding ring 320 and the rotating ring 330 are pressed together to form a second sealing surface 302 (e.g., ...). Figure 4 As shown), the moving ring 330 forms a gap with the first end face 311, and the second sealing surface 302 formed by the moving ring 330 and the second end face 321 seals the fluid cavity 100. Since the hardness of the sliding ring 320 is less than that of the stationary ring 310, the mechanical seal device 300 is less likely to generate a large amount of heat and burn out, thus improving the service life of the mechanical seal device 300. When the fluid F is in the second state, that is, when the fluid F contains more solid particles, the driving structure 340 moves along the first direction X, and the driving force of the driving structure 340 on the sliding ring 320 toward the moving ring 330 is released. Under the action of the elastic element 331, the moving ring 330 moves along the first direction X. One end face 321 abuts against the stationary ring 310 and fits tightly against the stationary ring 310 to form the first sealing surface 301. There is no additional driving force on the sliding ring 320 towards the moving ring 330, so that the second end face 321 fits tightly against the moving ring 330. At this time, the second end face 321 contacts or forms a gap with the moving ring 330. The first sealing surface 301 formed by the moving ring 330 and the first end face 311 plays a sealing role in the mechanical seal device 300. Since the hardness of the stationary ring 310 is greater than that of the sliding ring 320, the hardness of the materials constituting the second sealing surface 302 is relatively high. The mechanical seal device 300 is not easily worn by solids, which can improve the service life of the mechanical seal device 300.

[0134] In one embodiment, the mechanical seal device 300 includes multiple sliding rings 320 with different hardnesses. A drive structure 340 can drive each sliding ring 320 to move towards the rotating ring 330, so that each sliding ring 320 can be pressed against the rotating ring 330 to form a sealing surface. In another embodiment, the drive structure 340 simultaneously drives at least two sliding rings 320 to move towards the rotating ring 330, so that at least two sliding rings 320 simultaneously press against the rotating ring 330 to form a sealing surface. The arrangement of multiple sliding rings 320 further expands the applicable scenarios and scope of use of the mechanical seal device 300.

[0135] Please continue reading. Figure 3 In one possible implementation, the drive structure 340 abuts against or is fixedly connected to the end of the sliding ring 320 away from the moving ring 330. When the drive structure 340 abuts against the sliding ring 320, the sliding ring 320 moves away from the moving ring 330. This movement is achieved by the elastic force of the elastic element 331 on the moving ring 330, which in turn drives the sliding ring 320. When the drive structure 340 is fixedly connected to the sliding ring 320, the drive structure 340 can directly drive the sliding ring 320 to move away from the moving ring 330 along the first direction X. This allows the sliding ring 320 to move along the first direction X without relying on the elastic element 331. Furthermore, the drive structure 340 can drive the sliding ring 320 away from the moving ring 330, creating a gap between the second end face 321 and the moving ring 330. This allows the mechanical seal device 300 to respond faster to environmental changes and better adapt to environmental changes in the fluid F.

[0136] Please continue reading. Figure 3 In one possible implementation, the stationary ring 310 is fitted around the outer periphery of the sliding ring 320. The sliding ring 320 needs to move away from or towards the moving ring 330 in the first direction X. Positioning the sliding ring 320 inside the stationary ring 310 allows for a relatively small size, resulting in less friction between the sliding ring 320 and the stationary ring 310 or the shaft 200. This allows the drive structure 340 to more easily push the sliding ring 320 to slide in the first direction X.

[0137] In one possible implementation, when the driving force of the drive structure 340 on the second end face 321 toward the moving ring 330 is released, the first end face 311 and the second end face 321 are flush (e.g., Figure 3(As shown). If the first end face 311 and the second end face 321 are not flush, it complicates the process design. Furthermore, when the driving structure 340 drives the second end face 321, it needs to move an additional distance to contact the rotating ring 330. Alternatively, when the elastic element 331 makes the rotating ring 330 contact the first end face 311, the rotating ring 330 needs to move an additional distance, increasing the wear and tear on the mechanical seal device 300. However, if the first end face 311 and the second end face 321 are flush, on the one hand, this design reduces the difficulty of the manufacturing process and increases the working efficiency of the mechanical seal device 300, reducing working losses. On the other hand, the end face of the rotating ring 330 closest to the stationary ring 310 and the sliding ring 320 is a plane, resulting in high precision in the contact between the rotating ring 330 and the first end face 311 or the second end face 321.

[0138] Please continue reading. Figure 3 In one possible implementation, the stationary ring 310 is fitted onto the outer periphery of the sliding ring 320. The mechanical seal device 300 also includes a stationary ring support frame 312, which is used to fix the stationary ring 310 to the outer periphery of the stationary ring 310. The stationary ring 310 is fixedly connected to the stationary ring support frame 312 to prevent the stationary ring 310 from loosening during the operation of the fluid machinery device 10, which would reduce the sealing effect between the stationary ring 310 and the rotating ring 330.

[0139] In one possible implementation, the stationary ring support frame 312 includes a circumferential support portion 3121 connected to each other and an end face support portion 3122 located at one end of the circumferential support portion 3121 (e.g., ...). Figure 3 As shown, the peripheral support portion 3121 is used to fix the stationary ring 310 on the outer peripheral side of the stationary ring 310, and the end face support portion 3122 covers the end face of the stationary ring 310 away from the moving ring 330, exposing at least a portion of the end face of the sliding ring 320 away from the moving ring 330. The driving structure 340 is located on the inner peripheral side of the end face support portion 3122 and abuts against or is fixedly connected to the end face of the sliding ring 320 away from the moving ring 330 to drive the sliding ring 320 to move axially toward the moving ring 330.

[0140] In this embodiment, the end face of the sliding ring 320 away from the moving ring 330 is not covered by the end face support portion 3122, and the driving structure 340 abuts against or is fixedly connected to the end face of the sliding ring 320 away from the moving ring 330. In another embodiment, a portion of the end face of the sliding ring 320 away from the moving ring 330 is covered by the end face support portion 3122, exposing the portion of the end face of the sliding ring 320 away from the moving ring 330, and the structure of the driving structure 340 abuts against or is fixedly connected to the exposed end face of the sliding ring 320 (e.g., ...). Figure 8 (As shown).

[0141] In one embodiment, the end face support portion 3122 is provided with a through hole 3123 (e.g., ...) penetrating the end face support portion 3122. Figure 9 and Figure 10As shown, at least a portion of the end face of the sliding ring 320 away from the moving ring 330 is exposed. The driving structure 340 passes through the through hole 3123 and abuts against or is fixedly connected to the end face of the sliding ring 320 away from the moving ring 330. In this embodiment, the outer peripheral side of the stationary ring 310 and the end face away from the moving ring 330 are both covered by the stationary ring support frame 312, so that the stationary ring 310 is fixed in both the radial R and axial directions, enhancing the stability of the stationary ring 310. The portion of the end face of the sliding ring 320 away from the moving ring 330 is covered by the end face support portion 3122. There is a gap between the portion of the end face of the sliding ring 320 away from the moving ring 330 and the end face support portion 3122, so that the sliding ring 320 is limited between the moving ring 330 and the end face support portion 3122, preventing the sliding ring 320 from disengaging from the mechanical seal device 300 in the first direction X, thereby reducing the sealing effect of the mechanical seal device 300 and failing to achieve the purpose of multi-scenario applicability. In one embodiment, multiple through holes 3123 may be provided so that the driving structure 340 has sufficient driving force to drive the sliding ring 320 to move.

[0142] Please refer to Figure 11 In one possible implementation, the inner surface of the end face support 3122 is threadedly connected to the outer surface of the drive structure 340. The surface of the end face support 3122 that contacts the drive structure 340 is provided with threads 343, and the surface of the drive structure 340 that contacts the end face support 3122 is also provided with matching threads 343. The threads in the end face support 3122 and the threads in the drive structure 340 engage with each other, allowing the drive structure 340 to move in the first direction X through rotation. The threaded connection between the end face support 3122 and the drive structure 340 provides greater precision and controllability to the movement of the drive structure 340, improving the sealing effect of the mechanical seal device 300.

[0143] Please see Figure 12 In one possible implementation, the sliding ring 320 is fitted onto the outer periphery of the stationary ring 310. The stationary ring 310 is located between the sliding ring 320 and the shaft 200.

[0144] In one possible implementation, the mechanical seal device 300 further includes a stationary ring support frame 312, with a sliding ring 320 located between the stationary ring support frame 312 and the stationary ring 310. The stationary ring support frame 312 includes a circumferential support portion 3121 connected to each other and an end face support portion 3122 located at one end of the circumferential support portion 3121 (e.g., ...). Figure 12As shown, the peripheral support portion 3121 is located on the outer peripheral side of the sliding ring 320, and the end face support portion 3122 is used to fix the stationary ring 310 on the end face of the stationary ring 310 away from the moving ring 330. The end face support portion 3122 is provided with a through hole 3123 penetrating the end face support portion 3122, exposing at least a portion of the end face of the sliding ring 320 away from the moving ring 330. The driving structure 340 passes through the through hole 3123 and abuts against or is fixedly connected to the end face of the sliding ring 320 away from the moving ring 330 to drive the sliding ring 320 to move axially toward the moving ring 330. In this embodiment, the stationary ring 310 is fixedly connected to the end face support portion 3122, and the sliding ring 320 and the peripheral support portion 3121 can slide relative to each other.

[0145] In one embodiment, the end face support portion 3122 is provided with a plurality of through holes 3123 (e.g., Figure 13 As shown, the drive structure 340 passes through multiple through holes 3123 and abuts against or is fixedly connected to the sliding ring 320, giving the drive structure 340 sufficient driving force to drive the sliding ring 320 to move. In one embodiment, the outer surface of the drive structure 340 in contact with the through holes 3123 is threaded, and the inner surface of the through holes 3123 in contact with the drive structure 340 is threaded. The drive structure 340 is threadedly connected to the through holes 3123, giving the movement of the drive structure 340 more precise controllability. The sliding ring 320 is limited between the circumferential support portion 3121 and the stationary ring 310, and also limited between the end face support portion 3122 and the moving ring 330, improving the overall stability of the mechanical seal device 300 and allowing for better sealing performance.

[0146] In one possible implementation, a first sealing ring 350 is provided between the stationary ring 310 and the sliding ring 320 (e.g., Figure 3 and Figure 12 (As shown). The first sealing ring 350 seals the gap between the stationary ring 310 and the sliding ring 320, preventing fluid F from flowing out of the fluid cavity 100 from the gap between the stationary ring 310 and the sliding ring 320. The first sealing ring 350 can enhance the sealing performance of the mechanical seal device 300. The first sealing ring 350 is an elastic sealing ring and can be a rubber ring.

[0147] In one embodiment, a sliding ring 320 is sleeved on the outer periphery of a stationary ring 310, and a second sealing ring 351 is provided between the sliding ring 320 and the stationary ring support frame 312 (e.g., Figure 12 As shown, the second sealing ring 351 seals the gap between the sliding ring 320 and the stationary ring support frame 312, preventing fluid F from flowing out of the fluid cavity 100 from the gap between the sliding ring 320 and the stationary ring support frame 312. The second sealing ring 351 can enhance the sealing performance of the mechanical seal device 300.

[0148] In one embodiment, the stationary ring 310 is sleeved on the outer periphery of the sliding ring 320, and a second sealing ring 351 is provided between the stationary ring 310 and the stationary ring support frame 312 (e.g., Figure 3 As shown, the second sealing ring 351 seals the gap between the stationary ring 310 and the stationary ring support frame 312, preventing fluid F from flowing out of the fluid cavity 100 from the gap between the stationary ring 310 and the stationary ring support frame 312. The second sealing ring 351 can enhance the sealing performance of the mechanical seal device 300.

[0149] Please refer to it again. Figure 3 In one possible implementation, the drive structure 340 includes a drive motor 341 and a sliding ring adjusting rod 342. The sliding ring adjusting rod 342 is located at the end of the sliding ring 320 away from the moving ring 330. The drive motor 341 drives the sliding ring adjusting rod 342 to move axially, thereby causing the sliding ring 320 to move axially toward the moving ring 330. In this embodiment, the extension direction of the sliding ring adjusting rod 342 is a first direction X, and the extension direction of the sliding ring adjusting rod 342 is consistent with the axial direction of the sliding ring 320. The driving force of the sliding ring adjusting rod 342 acts directly on the sliding ring 320, which can better drive the movement of the sliding ring 320. In one embodiment, the extension direction of the sliding ring adjusting rod 342 is set at an angle to the axial direction of the sliding ring 320 (e.g., Figure 15 and Figure 16 As shown, the size of the mechanical seal device 300 in the first direction X can be reduced to adapt to the internal space environment of different fluid machinery equipment 10.

[0150] Please continue reading. Figure 15 In one embodiment, the extending direction of the sliding ring adjusting rod 342 is set at an angle to the axial direction of the sliding ring 320, wherein the angle is greater than 0° and less than or equal to 90°. The sliding ring 320 is sleeved on the outer periphery of the stationary ring 310. The peripheral support portion 3121 is provided with a channel 3124. The sliding ring adjusting rod 342 is connected to the sliding ring 320 by abutment or fixation through the channel 3124. The sliding ring 320 is limited between the end face support portion 3122 and the moving ring 330, and a gap 3125 is left between the end face support portion 3122 and the moving ring 330 so that the sliding ring 320 can move between the end face support portion 3122 and the moving ring 330. The sliding ring adjusting rod 342 can drive the sliding ring 320 to move along the first direction X or away from the first direction X within the channel 3124.

[0151] Please continue reading. Figure 16In one embodiment, the extending direction of the sliding ring adjusting rod 342 forms an angle with the axial direction of the sliding ring 320, wherein the angle is greater than 0° and less than or equal to 90°. The stationary ring 310 is sleeved on the outer periphery of the sliding ring 320. The peripheral support portion 3121 and the stationary ring 310 are provided with a groove 3124. The sliding ring adjusting rod 342 abuts, engages, or is fixedly connected to the periphery of the sliding ring 320 through the groove 3124. The end support portion 3122 and the moving ring 330 hold the sliding ring 320 in place. The sliding ring 320 is positioned between the end face support 3122 and the moving ring 330 with a gap 3125 reserved, allowing the sliding ring 320 to move between the end face support 3122 and the moving ring 330. The sliding ring adjusting rod 342 can drive the sliding ring 320 to move along or away from the first direction X within the channel 3124. The dimension of the channel 3124 along the first direction X is larger than the dimension of the sliding ring adjusting rod 342 along the first direction X, allowing the sliding ring adjusting rod 342 to move within the channel 3124 along the first direction X.

[0152] Please continue reading. Figure 10 and Figure 14 In one possible implementation, the sliding ring adjusting rod 342 has a hollow structure and is coaxially arranged with the sliding ring 320. The inner diameter of the sliding ring adjusting rod 342 is greater than or equal to the inner diameter of the sliding ring 320, and the outer diameter of the sliding ring adjusting rod 342 is less than or equal to the outer diameter of the sliding ring 320. In this embodiment, the stationary ring 310 is sleeved on the outer periphery of the sliding ring 320. The sliding ring adjusting rod 342 abuts against or is fixedly connected to the end face of the sliding ring 320 away from the moving ring 330. The fact that the inner diameter of the sliding ring adjusting rod 342 is greater than or equal to the inner diameter of the sliding ring 320 facilitates the sleeve of the sliding ring adjusting rod 342 on the shaft 200. Furthermore, when sliding relative to the shaft, it can reduce the friction between the sliding ring adjusting rod 342 and the shaft 200, improve the efficiency of the drive motor 341, and reduce energy consumption. The outer diameter of the sliding ring adjusting rod 342 is less than or equal to the outer diameter of the sliding ring 320, so that the friction between the sliding ring adjusting rod 342 and the stationary ring 310 is reduced during the process of driving the sliding ring 320 to move, thereby improving the efficiency of the drive motor 341 and reducing energy loss.

[0153] In one embodiment, the outer diameter of the sliding ring adjusting rod 342 is equal to the outer diameter of the sliding ring 320 (e.g., Figure 3 As shown), the inner diameter of the sliding ring adjusting rod 342 is equal to the inner diameter of the sliding ring 320. The end face of the sliding ring 320 away from the moving ring 330 is covered by the sliding ring adjusting rod 342. The two ends of the sliding ring 320 along the first direction X are limited between the moving ring 330 and the sliding ring adjusting rod 342. The contact area between the sliding ring adjusting rod 342 and the sliding ring 320 is large, or in other words, the force area between the sliding ring adjusting rod 342 and the sliding ring 320 is large, which is more conducive to driving the movement of the sliding ring 320.

[0154] In one embodiment, the sliding ring adjusting rod 342 is a cylindrical structure (e.g., Figure 12 and Figure 13 As shown, the sliding ring adjusting rod 342 abuts against or is fixedly connected to the end face of the sliding ring 320 away from the moving ring 330. The sliding ring adjusting rod 342 is disposed on the outer periphery of the shaft 200 and parallel to the shaft 200. The diameter of the sliding ring adjusting rod 342 is less than or equal to the difference between the outer diameter and the inner diameter of the sliding ring 320, so that the sliding ring adjusting rod 342 is less likely to be obstructed by the stationary ring 310 or the shaft 200 during the movement of the sliding ring 320, thus preventing it from continuing to move. In order for the sliding ring adjusting rod 342 to drive the movement of the sliding ring 320 more effectively, multiple sliding ring adjusting rods 342 can be provided. In one embodiment, the sliding ring adjusting rod 342 can also be a flat, arc-shaped, slender cuboid, which can be set according to actual needs.

[0155] In one embodiment, the sliding ring adjusting rod 342 abuts, engages, or is fixedly connected to the circumference of the sliding ring 320 (e.g., Figure 16 As shown, the diameter of the sliding ring adjusting rod 342 can be set according to actual needs to provide a more effective driving force.

[0156] Please continue reading. Figure 3 In one possible implementation, the mechanical seal device 300 further includes a detection device 360 ​​and a controller 370 (e.g., Figure 3 As shown), the detection device 360 ​​is used to detect the fluid state, and the controller 370 controls the drive structure 340 to drive the second end face 321 of the sliding ring 320 to move axially toward the moving ring 330 or release the driving force on the second end face 321 toward the moving ring 330 according to the fluid state.

[0157] In one embodiment, the detection device 360 ​​is a refractometer, which detects the refractive index of fluid F to distinguish the state of fluid F as a first state, a second state, or a third state. The detected state information of fluid F is fed back to the controller 370, which, after recognizing the information, controls the movement of the drive structure 340. In another embodiment, the detection device 360 ​​is a density analyzer, which detects the density of fluid F to distinguish the state of fluid F as a first state, a second state, or a third state. In one embodiment, the fluid machinery 10 is a pump 11, and the detection device 360 ​​is located on the inlet 102 side of the pump 11 to detect the state of the fluid entering the fluid chamber 100 from the inlet 102. In another embodiment, the detection device 360 ​​is located on the outlet 103 side of the pump 11 to detect the state of the fluid flowing out of the fluid chamber 100 from the outlet 103. In other embodiments, the detection device 360 ​​can also be an infrared detection device, a sensor, etc., as long as it can detect the first, second, or third state of the liquid.

[0158] Please see Figure 17 , Figure 1 and Figure 3 One embodiment of this application provides a mechanical seal method, applied to the fluid machinery device 10 as described above. The mechanical seal method includes steps S10 and S20:

[0159] Step S10: Obtain the fluid state within the fluid cavity 100.

[0160] In step S20, the second end face 321 of the sliding ring 320 is driven to move axially toward the moving ring 330 or the driving force on the second end face 321 toward the moving ring 330 is released according to the fluid state control drive structure 340.

[0161] In one embodiment, the fluid state includes a first state, a second state, and a third state. The first state is that the gas content in the fluid is greater than or equal to a first preset value, and the solid content in the fluid is less than a second preset value. The second state is that the solid content in the fluid is greater than or equal to the second preset value, and the gas content in the fluid is less than the first preset value. The third state is that the gas content in the fluid is less than the first preset value, and the solid content in the fluid is less than the second preset value.

[0162] In one possible implementation, when the sliding ring 320 has a first hardness and the stationary ring 310 has a second hardness, the first hardness is less than the second hardness, meaning the hardness of the sliding ring 320 is less than the hardness of the stationary ring 310. Step S20 includes steps S10-1 and S20-1 (e.g., ...). Figure 18 As shown):

[0163] Step S10-1: Determine whether the fluid state is the first state;

[0164] In step S20-1, when the fluid state is the first state, the control drive structure 340 drives the second sealing end 321 of the sliding ring 320 to move axially toward the moving ring 330, so that the second end face 321 and the moving ring 330 form a sealing surface, and a gap is formed between the first end face 311 and the moving ring 330. A mechanical seal is achieved through the sealing surface formed by the second end face 321 and the moving ring 330.

[0165] In one embodiment, step S20 further includes steps S11-1, S21-1, and S22-1 (e.g., ...). Figure 18 As shown):

[0166] Step S11-1: When the fluid state is not the first state, determine whether the fluid state is the second state.

[0167] In step S21-1, when the fluid state is the second state, the control drive structure 340 releases the driving force on the second end face 321 towards the moving ring 330, so that the first end face 311 and the moving ring 330 form a sealing surface. A mechanical seal is achieved through the sealing surface formed by the first end face 311 and the moving ring 330.

[0168] Step S22-1: When the fluid state is neither the first state nor the second state, the drive structure 340 does not operate. Here, the fluid state is neither the first nor the second state, meaning the fluid state is the third state. When the fluid is water, this can be understood as water in the third state containing only a small amount of air bubbles or a small amount of solid particles, or water in the third state containing neither air bubbles nor solid particles. The drive structure 340 not operating means that the drive structure 340 maintains its original state and does not further operate. That is, if the mechanical seal is currently formed by the sealing surface of the first end face 311 and the moving ring 330, the drive structure 340 does not operate, maintaining the current mechanical seal formed by the sealing surface of the first end face 311 and the moving ring 330; if the mechanical seal is currently formed by the sealing surface of the second end face 321 and the moving ring 330, the drive structure 340 does not operate, maintaining the current state. In other words, at this time, either the sealing surface formed by the first end face 311 and the moving ring 330 or the sealing surface formed by the second end face 321 and the moving ring 330 can achieve a seal.

[0169] In one possible implementation, when the sliding ring 320 has a second hardness and the stationary ring 310 has a first hardness, the first hardness is less than the second hardness, that is, the hardness of the stationary ring 310 is less than the hardness of the sliding ring 320. Step S20 includes steps S10-2 and S20-2 (as shown in the image). Figure 19 As shown):

[0170] Step S10-2: Determine whether the fluid state is the first state;

[0171] Step S20-2: When the fluid state is the first state, the control drive structure 340 releases the driving force on the second end face 321 toward the moving ring 330 so that the first end face 311 and the moving ring 330 form a sealing surface.

[0172] In one embodiment, step S20 further includes steps S11-2, S21-2, and S22-2 (e.g., ...). Figure 19 As shown):

[0173] Step S11-2: When the fluid state is not the first state, determine whether the fluid state is the second state.

[0174] Step S21-2: When the fluid state is the second state, the control drive structure 340 drives the second sealing end 321 of the sliding ring to move axially toward the moving ring 330 so that the second end face 321 and the moving ring 330 form a sealing surface, and a gap is formed between the first end face 311 and the moving ring 330.

[0175] In step S22-2, when the fluid state is neither the first state nor the second state, the fluid state is the third state, and the drive structure 340 does not work. The drive structure 340 not working means that it maintains its original state and does not operate further.

[0176] In this embodiment, the mechanical seal method is also applicable to fluid machinery equipment that includes the above-mentioned mechanical seal device. The structure of the mechanical seal device and the fluid machinery equipment is as described above and will not be repeated here.

[0177] The mechanical sealing device, fluid machinery equipment, and mechanical sealing method provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and embodiments of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in specific embodiments and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A mechanical seal device, characterized by, The mechanical seal device includes: The stationary ring includes the first end face; A sliding ring, including a second end face, is disposed inside the stationary ring or sleeved on the outside of the stationary ring along the radial direction of the stationary ring. The sliding ring and the stationary ring are fixed circumferentially along the stationary ring and can move relative to each other along the axial direction of the stationary ring. The stationary ring and the sliding ring have different hardness. A rotating ring is disposed at one end of the stationary ring and the sliding ring along the axial direction. The rotating ring elastically abuts against the first end face or the second end face along the axial direction. The rotating ring is located inside the fluid cavity of the fluid machinery. A driving structure is used to drive the second end face to move along the axial direction toward the moving ring, so that the second end face and the moving ring form a sealing surface, and a gap is formed between the first end face and the moving ring. When the driving force of the driving structure on the second end face toward the moving ring is released, the first end face and the moving ring abut against each other to form a sealing surface. The mechanical seal device achieves sealing inside and outside the fluid cavity of the fluid machinery through the sealing surface formed by the second end face and the moving ring or the sealing surface formed by the first end face and the moving ring.

2. The mechanical seal device according to claim 1, characterized by The hardness of one of the stationary ring and the sliding ring is a first hardness, and the hardness of the other of the stationary ring and the sliding ring is a second hardness. The first hardness is less than the second hardness, and the hardness of the moving ring is greater than or equal to the first hardness.

3. The mechanical seal device of claim 2, wherein The stationary ring has the first hardness, and the sliding ring has the second hardness.

4. The mechanical seal apparatus of claim 2, wherein The stationary ring has the second hardness, and the sliding ring has the first hardness.

5. The mechanical seal apparatus of claim 1, wherein The driving structure is abutted or fixedly connected to the end of the sliding ring away from the moving ring.

6. The mechanical seal apparatus of claim 1, wherein When the driving force of the driving structure on the second end face toward the moving ring is released, the first end face and the second end face are flush.

7. The mechanical seal apparatus of claim 1, wherein The stationary ring is sleeved on the outer circumferential side of the sliding ring, and the mechanical seal device further includes a stationary ring support frame, which is used to fix the stationary ring on the outer circumferential surface of the stationary ring.

8. The mechanical seal apparatus of claim 7, wherein The stationary ring support frame includes a peripheral support portion and an end face support portion located at one end of the peripheral support portion. The peripheral support portion is used to fix the stationary ring on the outer peripheral side of the stationary ring. The end face support portion covers the end face of the stationary ring away from the moving ring, exposing at least a portion of the end face of the sliding ring away from the moving ring. The driving structure is located on the inner peripheral side of the end face support portion and abuts against or is fixedly connected to the end face of the sliding ring away from the moving ring to drive the sliding ring to move axially toward the moving ring.

9. The mechanical seal apparatus of claim 8, wherein The inner surface of the end face support is threadedly connected to the outer surface of the drive structure.

10. The mechanical seal apparatus of claim 1, wherein The sliding ring is sleeved on the outer periphery of the stationary ring. The mechanical seal device further includes a stationary ring support frame. The stationary ring support frame includes a circumferential support portion and an end face support portion located at one end of the circumferential support portion. The circumferential support portion is located on the outer periphery of the sliding ring. The end face support portion is used to fix the stationary ring on the end face of the stationary ring away from the rotating ring. The end face support portion has a through hole that penetrates the end face support portion, exposing at least a portion of the end face of the sliding ring away from the rotating ring. The driving structure passes through the through hole and abuts against or is fixedly connected to the end face of the sliding ring away from the rotating ring to drive the sliding ring to move axially toward the rotating ring.

11. The mechanical seal device according to claim 1, characterized in that, A first sealing ring is provided between the stationary ring and the sliding ring.

12. The mechanical seal device according to claim 1, characterized in that, The drive structure includes a drive motor and a sliding ring adjusting rod. The sliding ring adjusting rod is located at the end of the sliding ring away from the moving ring. The drive motor is used to drive the sliding ring adjusting rod to move axially, thereby causing the sliding ring to move axially toward the moving ring.

13. The mechanical seal device according to claim 12, characterized in that, The sliding ring adjusting rod has a hollow structure and is coaxially arranged with the sliding ring. The inner diameter of the sliding ring adjusting rod is greater than or equal to the inner diameter of the sliding ring, and the outer diameter of the sliding ring adjusting rod is less than or equal to the outer diameter of the sliding ring.

14. The mechanical seal device according to claim 1, characterized in that, The mechanical seal device further includes a detection device and a controller. The detection device is used to detect the fluid state, and the controller controls the drive structure to drive the second end face of the sliding ring to move axially toward the moving ring or release the driving force on the second end face toward the moving ring according to the fluid state.

15. A fluid machinery device, characterized in that, The fluid machinery includes a fluid cavity, a shaft, and a mechanical seal as described in any one of claims 1-14. The fluid cavity is used to contain fluid. The shaft is installed inside the fluid cavity and extends outside the fluid cavity. The rotating ring, the stationary ring, and the sliding ring are sleeved on the shaft. The rotating ring is located inside the fluid cavity. The mechanical seal achieves sealing inside and outside the fluid cavity through the sealing surface.

16. The fluid machinery device according to claim 15, characterized in that, The fluid machinery also includes an impeller and a motor. The impeller is located inside the fluid cavity and is fixedly connected to the shaft. The motor is located outside the fluid cavity and is connected to the shaft. The motor is used to drive the shaft to rotate, and the rotation of the shaft drives the impeller to rotate.

17. The fluid machinery device according to claim 15, characterized in that, The fluid machinery equipment is a pump, centrifuge, reactor, or compressor.

18. A mechanical sealing method, characterized in that, When applied to a fluid machinery device as described in any one of claims 15-17, the mechanical seal method comprises: Obtain the fluid state within the fluid cavity; According to the fluid state, the drive structure is controlled to drive the second end face of the sliding ring to move axially toward the moving ring or to release the driving force on the second end face toward the moving ring.

19. The mechanical seal method according to claim 18, characterized in that, When the hardness of the sliding ring is a first hardness and the hardness of the stationary ring is a second hardness, controlling the driving structure according to the fluid state to drive the second end face of the sliding ring to move axially toward the moving ring or to release the driving force on the second end face toward the moving ring includes: Determine whether the fluid state is a first state, wherein the first state is that the gas content in the fluid is greater than or equal to a first preset value, and the solid content in the fluid is less than a second preset value; When the fluid state is the first state, the drive structure is controlled to drive the second end face of the sliding ring to move axially toward the moving ring, so that the second end face and the moving ring form a sealing surface, and a gap is formed between the first end face and the moving ring.

20. The mechanical seal method according to claim 18, characterized in that, When the hardness of the sliding ring is a first hardness and the hardness of the stationary ring is a second hardness, controlling the driving structure according to the fluid state to drive the second end face of the sliding ring to move axially toward the moving ring or to release the driving force on the second end face toward the moving ring includes: Determine whether the fluid state is a second state, wherein the second state is that the solid content in the fluid is greater than or equal to a second preset value, and the gas content in the fluid is less than a first preset value; When the fluid state is the second state, the drive structure is controlled to release the driving force on the second end face toward the moving ring, so that the first end face and the moving ring form a sealing surface.

Images