Non-propulsive dry gas seal with a sealing elastomer and system using the same

Abstract

A seal, which can be used alone or as a containment seal for another seal, includes a primary ring axially displaceable relative to a rotating shaft, a mating ring axially fixed relative to the shaft, a biasing mechanism urging the primary ring toward the mating ring, and an annular flexible seal membrane. The membrane includes a flange portion disposed at least partially between the biasing mechanism and the primary ring, a coaxial portion axially fixed relative to the shaft, and a flexible connecting portion positioned within a radially inward extent of the flange portion and connecting the flange portion to the coaxial portion. At least one of the mating ring and the primary ring includes a groove formed in a surface thereof that causes a gas film to be formed between the primary ring and the mating ring that prevents the primary ring and the mating ring from contacting one another in operation.

Description

Technical Field

[0001] Exemplary embodiments relate to the field of dry gas sealing, and particularly to non-propelled dry gas seals that can be used alone or as a primary seal. Background Technology

[0002] Several types of seals are available for providing a seal between the rotating shaft and stationary housing of pumps, compressors, turbines, or other rotating machinery. One example is a face mechanical seal. This seal consists of a sealing interface formed by two faces that contact each other. In operation, one face rotates with the rotating shaft, while the other face remains stationary. Frictional wear between the sealing faces can cause a gap to form between the two faces, resulting in excessive leakage. Therefore, this type of seal requires periodic adjustment to maintain the proper, or axial, position of the faces relative to each other, thus mitigating wear while still maintaining a relatively leak-free seal. Of course, no matter how well these faces are manipulated, some leakage can still occur.

[0003] Various biasing mechanisms have been considered to provide closing force to automatically adapt to wear and push the sealing surfaces together. Such biasing mechanisms include single and multiple helical springs as well as metal bellows. Those skilled in the art will recognize that the total closing force is actually a combination of the hydraulic pressure of the sealing fluid and the force provided by the biasing mechanism.

[0004] If the sealing surfaces rotate relative to each other without some form of lubrication, surface friction will lead to excessive friction and heat generation, resulting in premature failure. Therefore, some form of lubrication is required between the rotating and stationary sealing surfaces. In a typical mechanical seal, lubrication is maintained by forming a fluid film between the sealing surfaces. This film can originate from a pumped / compressed fluid or from an external source.

[0005] One type of seal comprising two faces is called a "propelled seal." In a propelled seal, a dynamic secondary seal (such as an O-ring) is provided to form a seal between the shaft (or an element connected to the shaft) and a face that moves axially relative to the shaft, preventing fluid from bypassing the face and escaping. Axial movement of the face can cause wear or tearing of the secondary seal due to friction.

[0006] Another type of seal uses a wound elastomeric bellows. This type of seal uses a spring-loaded bellows instead of O-rings. This type of seal is sometimes difficult to implement under high-pressure operating conditions.

[0007] In situations where gases are pumped, compressed, blown, etc., non-contact or "gas" seals can be used instead of mechanical seals. An example of such a seal is a dry gas seal. Dry gas seals are commonly used to seal centrifugal compressors, which are typically used to transport and distribute gases, such as natural gas. For example, in a natural gas pipeline, the compressor can be positioned at set intervals to increase the pressure of the gas being processed to offset the effects of flow losses along the transmission pipeline and generally to keep the gas moving toward its destination. Similar to mechanical seals, dry gas seals consist of two rings that define faces that rotate relative to each other.

[0008] The swivel ring is sometimes called the "matching ring" because it engages with the rotating shaft / rotor. The swivel ring can be fitted to the rotor via a bushing. The stationary ring is sometimes called the main ring and does not rotate during operation.

[0009] In operation, a gas layer is formed between the two rings, creating a seal while allowing the rings to move relative to each other without contacting each other. The gas layer is formed by process gas or sealing gas injected into the dry gas seal. A groove in the rotating (mating) ring draws gas from the radially outer edge of the mating ring to a position between the two rings. The gas drawn into the groove is compressed as it moves toward the radially inner end (or tip) of the groove. The compressed gas creates a pressure dam that causes the master ring to “lift off” from the mating ring, creating an operating gap in the range of a few micrometers (e.g., 3-10 μm). Similarly, to allow relative axial movement between the rings, the master ring is typically mounted to the stationary portion of the dry gas seal by a compressible member such as a spring or other device. After lifting off, a very small amount of process gas flows across the dam-like area to the low-pressure side of the seal (e.g., outside the compressor), creating controlled seal leakage, and the ring operates as a non-contact seal on a thin film of gas. Such seals may include the aforementioned O-rings to seal gas and prevent it from bypassing the ring, thus having some of the same problems. Summary of the Invention

[0010] One embodiment discloses a non-contact seal. The non-contact (or dry gas) seal can be used as a standalone seal or in combination with a main seal as a containment or "backup" seal.

[0011] In one embodiment, the seal is adapted to be arranged about a rotation axis and includes a main ring and a mating ring. The main ring is axially displaceable relative to the rotation axis, and the mating ring is axially fixed relative to the rotation axis. The seal also includes a biasing mechanism that pushes the main ring toward the mating ring and the annular flexible sealing membrane.

[0012] An annular flexible sealing membrane seals gas, preventing its flow around the seal created by the ring (e.g., a face), without being restricted by an O-ring. Furthermore, it has been found that under high pressure, the gyroscopic elastomer bellows can collapse radially inward toward the axis of rotation, causing a change in the way and / or position of the bellows / spring applying pressure on the main ring. This change affects one or both of the seal balance or surface load, which significantly reduces the performance and predictability of non-contact applications using such bellows.

[0013] The annular flexible sealing membrane used here does not collapse like a conventional elastomer. This results in a constant (or near-constant) seal balance and constant face load throughout the sealing operation, even under high pressure.

[0014] In one embodiment, the annular flexible sealing membrane includes a flange portion at least partially disposed between the biasing mechanism and the main ring, a coaxial portion that can be axially fixed relative to the shaft, and a flexible connecting portion positioned within a radially inward range of the first flange portion and connecting the first flange portion to the first coaxial portion.

[0015] In this seal, at least one of the mating ring and the main ring includes a groove formed on its surface, which allows an air film to form between the main ring and the mating ring, thereby preventing them from contacting each other during operation. The groove can be bidirectional or unidirectional.

[0016] The aforementioned seals can be used alone or as a sealing device for the main (or first) seal in pump applications. The receiving seal is located downstream of the main seal. In this context, "upstream" refers to a location closer to the pump or other machine where most of the liquid being processed is located further downstream.

[0017] As discussed more fully below, in some cases, the primary seal is any type of rotary seal that forms a seal around a rotating shaft (e.g., the rotating shaft of a pump) and comprises two faces / rings that can rotate relative to each other and are lubricated by a liquid. In some cases, the lubricant leaking between the rings becomes vapor. This can happen, for example, when pumping light hydrocarbons such as propane, butane, gasoline, or naphtha. Vapor can be directed from the primary seal into a non-contact receiving seal, causing the primary and mating rings of that seal to separate and not contact each other. In this configuration, the non-contact seal can operate as a backup seal to the primary seal but does not suffer from the same surface wear as a contact seal.

[0018] Furthermore, in one embodiment, some or all of the coaxial portion and flexible connection portion of the annular flexible sealing membrane are supported by an annular stub sleeve. This prevents or reduces any collapse of the annular flexible sealing membrane and keeps the receiving seal in an operationally advantageous position, regardless of the pressure or operating conditions of the main seal. Of course, the stub sleeve can be replaced by another element supporting the annular flexible sealing membrane.

[0019] Because the receiving seal operates in a non-contact manner, its expected lifespan should be longer than that of the main seal, and it should continue to function even if the main seal fails. This ensures that, if needed, the receiving seal can be used as a backup to the main seal to fulfill its intended purpose.

[0020] In one specific embodiment, a mechanical seal assembly suitable for arrangement around a rotating shaft of a pump is disclosed. This embodiment includes two seals, both having annular flexible sealing elements. More specifically, the sealing assembly of this embodiment may include a first seal comprising: a first main ring and a first mating ring, the first main ring being axially displaceable relative to the rotating shaft and the first mating ring being axially fixed relative to the rotating shaft; a first biasing mechanism that pushes the first main ring toward the first mating ring; and a first annular flexible sealing membrane. The first annular flexible sealing membrane includes: a first flange portion at least partially disposed between the first biasing mechanism and the first main ring; a first coaxial portion axially fixed relative to the shaft; and a first flexible connecting portion positioned radially inward of the first flange portion and connecting the first flange portion to the first coaxial portion. In operation, a liquid film is formed between the first main ring and the first mating ring by a first liquid within the pump, the first liquid in the liquid film generating a gaseous form of the first liquid after passing through the first seal, the gas being supplied to a receiving cavity. The assembly further includes: a second seal in fluid communication with the receiving cavity, the second seal comprising: a second main ring and a second mating ring, the second main ring being axially displaceable relative to the rotation axis and the second mating ring being axially fixed relative to the rotation axis; a second biasing mechanism that pushes the second main ring toward the second mating ring; and a second annular flexible sealing membrane. The second annular flexible sealing membrane comprises: a second flange portion at least partially disposed between the second biasing mechanism and the second main ring; a second coaxial portion axially fixed relative to the axis; and a second flexible connecting portion positioned radially inward of the second flange portion and connecting the second flange portion to the second coaxial portion. At least one of the second mating ring and the second main ring includes a groove formed on its surface, the groove causing the formation of an air film between the second main ring and the second mating portion, the air film being at least partially formed by gas passing through the first seal in the receiving cavity, the air film preventing the second main ring and the second mating ring from contacting each other during operation.

[0021] In another embodiment, a sealing assembly suitable for arrangement around the rotating shaft of a pump is disclosed. In this embodiment, the first or main seal may or may not include an annular flexible sealing membrane, and instead, it may be any type of seal for rotating machinery, including a main ring and a second ring. Specifically, in this embodiment, the assembly includes a first seal comprising: a first main ring; a first mating ring; and a first biasing mechanism that pushes the first main ring toward the first mating ring. In operation, a liquid film is formed between the first main ring and the first mating ring by a first liquid within the pump, and the first liquid in the liquid film generates a gaseous form of the first liquid after passing through the first seal. The gas is provided into a receiving cavity. The assembly also includes a second seal in fluid communication with the receiving cavity. The second seal comprises: a second main ring and a second mating ring, the second main ring being axially displaceable relative to the rotating shaft and the second mating ring being axially fixed relative to the rotating shaft; a second biasing mechanism that pushes the second main ring toward the second mating ring; and a second annular flexible sealing membrane. The second annular flexible sealing membrane includes: a second flange portion at least partially disposed between the first biasing mechanism and the first main ring; a second coaxial portion axially fixed relative to the shaft; and a second flexible connecting portion positioned radially inward of the second flange portion and connecting the second flange portion to the second coaxial portion. At least one of the second mating ring and the second main ring includes a groove formed on its surface, which allows a gas film formed by gas in the receiving cavity to pass through the first seal and form between the second main ring and the second mating ring, the gas film preventing the second main ring and the second mating ring from contacting each other during operation.

[0022] In any of the components described in the foregoing embodiments, the liquid is a light fraction with a specific gravity of less than 0.7.

[0023] In any of the components of the foregoing embodiments, the liquid is propane, butane, gasoline, or naphtha.

[0024] In any of the components described in the foregoing embodiments, the groove may be a unidirectional groove or a bidirectional groove.

[0025] In any of the components described in the foregoing embodiments, the first seal and the second seal are disposed within a cylinder. The cylinder may be at least partially disposed within the pump.

[0026] In any of the components described above, the second seal is in fluid communication with the first seal inside the cylinder.

[0027] In any of the components described above, the second coaxial portion may be arranged at a diameter within the balance diameter of the sealing assembly.

[0028] In any of the components of the foregoing embodiments, during operation, axial translation of the rotation axis relative to the second biasing mechanism causes the second flange portion to be axially and radially displaced relative to the second coaxial portion.

[0029] In any of the components of the foregoing embodiments, during operation, axial translation of the rotation axis relative to the second biasing mechanism causes the second flange portion to be axially and radially displaced relative to the second coaxial portion.

[0030] In any of the components described in the foregoing embodiments, the second flexible connection portion has a thinner cross-section than the second flange portion and the second coaxial portion.

[0031] In any of the components of the foregoing embodiments, the component may include an anti-crushing ring that may be received within a groove of the first axially displaceable sealing ring.

[0032] In any of the foregoing embodiments, the component further includes a rotary sleeve operably coupled to the rotary shaft for rotation therewith, and wherein the first axially fixed sealing ring and the second axially fixed sealing ring are operably coupled to the rotary sleeve.

[0033] In any of the components described above, the second sealing membrane comprises a flexible elastomer.

[0034] A mechanical seal suitable for arrangement around a rotating shaft is also disclosed. The seal includes: a main ring and a mating ring, the main ring being axially displaceable relative to the rotating shaft and the mating ring being axially fixed relative to the rotating shaft; a biasing mechanism that pushes the main ring toward the mating ring; and an annular flexible sealing membrane. The annular flexible sealing membrane includes: a flange portion at least partially disposed between the biasing mechanism and the main ring; a coaxial portion that is axially fixed relative to the shaft; and a flexible connecting portion positioned radially inward of the flange portion and connecting the flange portion to the coaxial portion. In this seal, at least one of the mating ring and the main ring includes a groove formed on its surface, the groove causing an air film to form between the main ring and the mating ring, the air film preventing the main ring and the mating ring from contacting each other during operation.

[0035] In any of the mechanical seals described in the foregoing embodiments, the groove may be a one-way groove or a two-way groove.

[0036] In any of the mechanical seals described in the foregoing embodiments, the coaxial portion may be arranged at a diameter within the balance diameter of the seal.

[0037] In any of the mechanical seals described above, the axial translation of the rotating shaft relative to the biasing mechanism causes the flange portion to be axially and radially displaced relative to the coaxial portion.

[0038] In any of the mechanical seals described in the foregoing embodiments, the axial translation of the rotating shaft relative to the biasing mechanism causes the flange portion to be axially and radially displaced relative to the coaxial portion.

[0039] In any of the mechanical seals described in the foregoing embodiments, the connecting portion has a thinner cross-section than the flange portion and the coaxial portion.

[0040] In any of the mechanical seals described in the foregoing embodiments, the mechanical seal may include an anti-compression ring that may be received within a groove of an axially displaceable sealing ring.

[0041] In any of the mechanical seals described in the foregoing embodiments, the short sleeve is axially fixed to the biasing mechanism by a retaining ring.

[0042] In any of the mechanical seals described in the foregoing embodiments, the biasing mechanism includes an axially movable annular retainer near the flange portion, an annular carrier axially fixed to the gland plate, and a plurality of radially spaced spring members disposed therebetween.

[0043] In any of the mechanical seals of the foregoing embodiments, the seal may further include a rotating sleeve operably coupled to a rotating shaft to rotate therewith, and wherein an axially fixed sealing ring is operably coupled to the sleeve.

[0044] In any of the mechanical seals described in the foregoing embodiments, the sealing membrane comprises a flexible elastomer.

[0045] In any prior embodiment, any disclosed stub sleeve may include a first outer diameter, a second outer diameter, and an angled surface connecting the first outer diameter to the second outer diameter, wherein the second outer diameter is larger than the first outer diameter. In such an embodiment, the first outer diameter of the stub sleeve may abut a coaxial portion, the angled surface may abut an angled facet of a flexible connection portion, and the second outer diameter may abut an axially displaceable first sealing ring.

[0046] In any existing embodiment, any existing flexible connection portion may include an angled facet that extends from the flange portion in an axially outward direction and forms an angle φ with the coaxial portion, wherein the angle φ is between 100° and 150°.

[0047] Additional technical features and benefits are achieved through the technology of this invention. Embodiments and aspects of the invention are described in detail herein and are considered part of the claimed subject matter. For a better understanding, refer to the detailed description and accompanying drawings.

[0048] Brief description of the attached figures

[0049] The proprietary details described herein are specifically pointed out and clearly claimed in the claims at the end of the specification. The foregoing and other features and advantages of embodiments of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0050] Figure 1 It is a cross-sectional view depicting a portion of a sealing assembly comprising two seals, the two seals including a primary seal formed as a contact O-ring push-type seal and a second or receiving seal formed as a non-push-type seal including a non-shrinkable flexible sealing membrane;

[0051] Figure 2 It is a cross-sectional view depicting a portion of a sealing assembly including a non-collapseable flexible sealing membrane according to one embodiment;

[0052] Figure 3 It describes an embodiment Figure 2 Detailed cross-sectional view of the sealing assembly;

[0053] Figure 4A and 4B It shows when the shaft moves Figure 2 and 3 A cross-section of a portion of the sealing assembly;

[0054] Figure 5 It is a description Figure 2 and Figure 3 A cross-sectional view of a portion of the sealing assembly;

[0055] Figure 6 An example of a face of a sealing ring including a one-way groove is shown;

[0056] Figure 7 An example of a sealing ring face including a bidirectional groove is shown; and

[0057] Figure 8 It is a cross-sectional view depicting a portion of a sealing assembly comprising two seals, including a first or main seal and a second or receiving seal, both of which are formed as non-propelled seals comprising a non-collapseable flexible sealing membrane.

[0058] The figures described herein are illustrative. Many variations may be made to the figures or operations described herein without departing from the spirit of the invention. For example, actions may be performed in a different order, or actions may be added, deleted, or modified. Furthermore, the terms "connection," "link," and variations thereof describe a path for fluid between two elements and do not imply a direct connection between the elements without any intermediate elements / links between them. However, all connections or links may be direct if the claims are explicitly stated, and if all instances of such connections / links can include a direct description of a connection / coupling (or similar term). All such variations are considered part of the specification. Detailed Implementation

[0059] With reference to the accompanying drawings, a detailed description of one or more embodiments of the disclosed apparatus and methods is presented herein by way of example and not limitation.

[0060] Turning now to an overview of technology more specifically related to aspects of the present invention, a seal is disclosed that can be used as a stand-alone seal in any machine including a rotating shaft, or as a spare in such a machine. Examples of such machines include pumps, mixers, agitators, stirrers, compressors, blowers, fans, etc.

[0061] When the seal is a "standby" (or "containment") seal, the primary seal can be any type of rotary seal that creates a seal around a rotating shaft and comprises two faces / rings that can rotate relative to each other and are lubricated by a liquid. In some cases, the lubricant leaking between the rings turns into vapor. This can happen, for example, when pumping light hydrocarbons such as propane, butane, gasoline, or naphtha. In refineries, heating crude oil causes vapor to rise through a tower, where it condenses at different levels. Those that accumulate at the highest point are sometimes referred to as light fractions. Here, light fractions are any process fluids with an SVP (saturated vapor pressure) above 1 bar (14.7 psi) at ambient temperature. Typically, it is a fluid with a specific gravity less than 0.7. While this article discusses gases / vapors from light fractions, it should be understood that containment seals can be used with other types of gases.

[0062] Vapor can be guided from the primary seal to the non-contact receiving seal, causing the faces of the primary and mating rings of that seal to separate and not contact each other. If the primary seal fails, the vapor film will be replaced by liquid, and the receiving seal will operate as a typical mechanical seal, comprising two faces lubricated by the contained liquid.

[0063] Now for reference Figure 1An embodiment of a mechanical seal assembly 1 according to one embodiment is shown. The mechanical seal assembly includes first and second seals 2, 3. As shown, the first seal 2 is arranged such that it is located at... Figure 1 The inner side of the second seal 3, the terms first and second can be replaced by the terms "main" and "retaining" or "alternate," respectively. It should be understood that the first and second seals can be identical or similar to each other. For example, in... Figure 1 In this context, the first seal 2 can be referred to as the main seal, while the second seal 2 is referred to as the receiving seal. In some cases, the second seal can be used alone, and in such cases, it can be referred to as the first seal.

[0064] Return to reference Figure 1 The component 1 shown has a main seal 2, illustrated as an O-ring type push seal, and a receiving seal 3, illustrated as a seal including an annular flexible sealing membrane 100. Of course, the first seal 2 may also include an annular flexible sealing membrane (e.g., see below). Figure 8 ).

[0065] Figure 1 Component 1 (and all other sealing components or individual seals shown herein) may be a freestanding component, or it may be assembled and inserted into the hole 6 formed in the rotating machine such that it revolves around the machine's axis of rotation 12. For simplicity, only the annular housing 18 of the machine is shown, but this will serve as an illustration for any type of machine.

[0066] Component 1 seals the liquid within a chamber 7, such as a pumping or process gas chamber. For example, in one embodiment, chamber 7 comprises a light distillate in a liquid state. Here, sealing component 1 may provide a seal for chamber 7 relative to the surrounding environment 16 at an inner extent of sealing component 1.

[0067] The main seal 2 shown includes two rings 4 and 5, which have opposing faces 8 and 9 that rotate relative to each other during operation. Further explanation will follow. Figure 1 The main seal 2 operates primarily based on a typical O-ring advance seal and generally functions as a lubricating mechanical seal. Thus, as the surfaces rotate relative to each other, a liquid film forms between them. Liquid is received from chamber 7, typically held on the inner side 60 where the surfaces meet at 4 / 5. As described above, some liquid will lubricate these surfaces, and a small amount of liquid can pass between these surfaces during operation (leakage). If the liquid is a light distillate, the leakage through the main seal 2 becomes vapor. Therefore, on the outer side 62 of the main seal 2, the light distillate exits as gas / vapor.

[0068] The outer side 62 of the receiving seal 3 is in fluid communication with the outer side of the main seal 2. Figure 1 The unmarked arrows indicate the path of fluid (gas or liquid) through the main seal 2 (e.g., the gas / liquid path on the outer side 62 and within assembly 1). As shown, the main seal 2 and the receiving seal 3 are arranged such that a receiving cavity 63 is defined between them. Typically, the receiving cavity 63 operates at low pressure, and there is no liquid at the sealing surfaces 30', 36'. Conventional leakage from the main seal 2 is discharged through the vent 90 or otherwise. However, if the main seal 2 fails, liquid reaches the sealing surfaces 30', 36'. Since it now operates under pumped liquid pressure conditions and has liquid-lubricated sealing surfaces 30', 36', the receiving seal 3 prevents pumped liquid from reaching the atmosphere 18.

[0069] As described above, in normal operation, the fluid in the receiving cavity 63 is gas, and a portion of the receiving seal 3 can be used to enable it to operate as a dry, non-contact seal.

[0070] In one embodiment, at least one of the two sealing surfaces 30', 36' includes a unidirectional or bidirectional groove formed therein, such that the receiving seal 3 operates as a dry-running seal, wherein the surfaces are separated by a gas film generated by gas / vapor received from the outer side 62 of the main seal 2.

[0071] In fact, it has been found that the dry-running capability of using a non-contact seal in a receiving seal can provide a more reliable backup than providing another seal with a contact sealing surface similar to that of the main seal 2 (e.g., liquid-lubricated). This is due to the fact that, in the event of failure of the main seal, such a receiving seal can wear at a rate similar to that of the main seal 2, thus producing its performance as a backup for the main seal in the event of failure of the main seal.

[0072] In the example above, during normal operation, the pressure in the outer side 62 of the main seal 2 is relatively low (e.g., approximately 40 PSI). However, in the event of main seal failure, this pressure increases rapidly.

[0073] One type of dry-running seal is the so-called "cycloid" seal. However, under high pressure, the elastomer may collapse (or at least move radially inward / outward), and therefore, when it collapses, it affects the performance or predictability of this seal.

[0074] Furthermore, pipeline pumps exhibit high reciprocating shaft motion. If dry-running O-ring push-type seals are used, it has been found that the O-rings can wear or otherwise deteriorate, leading to seal failure. Therefore, such seals may be unreliable as backup seals.

[0075] Based on these factors discovered by the inventors, instead of O-ring propulsion or rotary elastomer dry-running seals, the containment seal 3 can be implemented as a dry-running non-contact seal including a non-collapseable bellows. Figure 1 In the diagram, the non-collapseable bellows is shown as an annular flexible sealing membrane 100. The annular flexible sealing membrane 100 is non-collapseable and can be supported, for example, by a short sleeve 200. As described more fully below, because the annular flexible sealing membrane 100 has no relative movement with respect to the short sleeve 200, it does not wear like a conventional O-ring.

[0076] In this case (as shown more fully below), the receiving seal 3 includes a main ring 36 and a mating ring 30. The main ring 36 is axially movable relative to the rotation shaft 12, and the mating ring 30 is axially fixed relative to the rotation shaft 12. One of these rings includes a face (e.g., faces 36' and 30'), and one of them may have a unidirectional or bidirectional groove formed therein. Figure 6 An example of a one-way groove 72 is shown on the sealing surface (surface 36' or face 30'). Figure 7 A bidirectional groove 74 is shown on the sealing surface (surface 36' or face 30'). The groove formed on one of faces 36' and 30' allows a gas film formed by the gas passing through the main seal 2 to form between the main ring 36 and the mating ring 30, which keeps them from contacting each other during normal operation. The formation of this gas film is generally due to the fact that the gas is compressible and is often referred to as "lift-off".

[0077] The biasing mechanism 500 (e.g., a spring) pushes the main ring 36 toward the matching ring 30. Figure 1 The annular flexible sealing membrane 100 shown and further discussed below includes a flange portion 102 at least partially disposed between the biasing mechanism 500 and the main ring 36, a coaxial portion 104 axially fixable relative to the shaft 12, and a flexible connecting portion 106 connecting the flange portion 102 to the coaxial portion 104. Further details of the annular flexible sealing membrane 100 are provided below.

[0078] In the event of failure of the main seal 2, liquid, rather than gas, will be present on the outer surface 62 of the main seal 2 (i.e., the receiving cavity 63 will be filled with liquid). Since liquid is incompressible, the groove on the face of one of the sealing rings 30, 36 will not cause the aforementioned lift-off. In this case, the biasing mechanism 500 will force faces 36', 30' together, and the secondary seal 3 will operate as a contact seal. However, because the receiving seal 3 operates in a non-contact manner until the main seal fails, faces 36', 30' are essentially "new" and will provide a reliable seal in the event of such failure.

[0079] As shown in the figure, the sealing assembly 1 is disposed in the hole 6 formed in the annular housing 18. More specifically, the annular sleeve member 22 is fixedly attached to the shaft 12 and rotates with it. Figure 1 In the example shown, regarding the main seal 2, the first or main ring 4 is supported on the annular sleeve 22, and the second or mating ring 5 is supported by a carrier ring 92, which is fixedly connected to the annular housing 18 during operation. In this example, the main or first seal biasing mechanism 502 pushes the main ring 4 and the secondary ring 5 of the main seal together. Specifically, the main or first seal biasing mechanism 502 is connected to the main ring 4 and pushes it toward the mating ring 5. Of course, this configuration can be reversed without departing from the teachings herein.

[0080] The receiving seal carrier 94 carries the main ring 36 of the secondary seal, as well as the stub sleeve 200, the biasing mechanism 500, and the annular flexible sealing membrane 100. The receiving seal carrier 94 may be referred to as a pressure plate and may be the same as or similar to the pressure plate 20 described below. Similar to the main ring 4, the mating ring 30 of the receiving seal 3 is carried by and rotates with the annular sleeve 22. In this and other embodiments, the receiving seal carrier 94 and the carrying ring 92 may be joined together to form a cylinder. In this and other embodiments, the cylinder thus formed may be connected to the annular housing 18. In some cases, the cylinder may include an end plate 17 connecting the receiving seal carrier 94 to the annular sleeve component 22. In one embodiment, the cylinder may define a receiving cavity 23.

[0081] A more detailed example of a seal comprising an annular flexible sealing membrane 100 will now be described. This description will include one form of such a seal, namely, although it may have the same... Figure 1 The accommodating seals have three different appearances for the main ring and mating ring, but the same principle applies. However, it should be noted that... Figure 1 The receiving seal 3 does not include an anti-compression ring. This does not mean that such a device cannot include... Figure 1 The accommodating seal 3 is not included, but can be omitted. This is true because during normal operation, Figure 1 The receiving seal 3 operates at relatively low pressure, and it is assumed that if the main seal 2 fails (e.g., when the pressure on the receiving seal 3 increases), the pump or other machinery will shut down. In one embodiment, only the receiving seal is arranged and constructed as now described. In another embodiment, both the main seal and the receiving seal can be arranged and constructed in this way.

[0082] Figure 2 and 3The images depict a wide and detailed cross-sectional view of a portion of a sealing assembly 10 according to an embodiment of the present disclosure, the sealing assembly including a flexible, non-collapseable sealing membrane 100 depicted in conjunction with an object of a rotating shaft device such as a pump, mixer, agitator, stirrer, compressor, blower, fan, etc.

[0083] As is common for this type of sealing assembly, sealing assembly 10 seals the axially extending shaft 12 of a rotating shaft device for the rotation of an object. Sealing assembly 10 can provide a seal for the process chamber 14 within the inner portion of the sealing assembly 10 relative to the surrounding environment 16, see again. Figure 1 Those skilled in the art will recognize that process chamber 14 can be chamber 7 (in the case of providing only one seal) or Figure 1 The accommodating chamber 63 described herein.

[0084] The sealing assembly 10 may be coaxially disposed in a bore defined by an annular housing 18 coaxial with the shaft 12. Various fixed (or non-rotating) components of the sealing assembly 10 may be operatively connected to the housing 18 or a pressure plate 20, which in turn is operatively connected to the housing 18.

[0085] Various rotating components can be operatively coupled to shaft 12 for rotation with it. An annular sleeve member 22 is fixed to shaft 12 for rotation with it. An annular flange structure 26 extends radially outward from sleeve member 22 at its end adjacent to process chamber 14. A plurality of annularly spaced pins 24 can extend axially through holes in sleeve flange 26.

[0086] An axially fixed sealing ring 30 (or mating ring) is mounted on the surface of the sleeve flange 26 remote from the process chamber 14 to rotate with it. An annular O-ring 32 provides a resilient secondary seal between the sleeve component 22 and the axially fixed sealing ring 30. In embodiments, more or fewer secondary sealing O-rings may be present. The axially fixed sealing ring 30 includes an outer sealing surface 50.

[0087] An axially movable sealing ring 36 (or main ring) is arranged on the outer side and adjacent to the axially fixed sealing ring 30. The axially movable sealing ring 36 includes an inner sealing surface 52. The inner sealing surface 52 abuts the outer sealing surface 50. The sealing surfaces 50 and 52 may correspond to Figure 1 The sealing surfaces are 30' and 36'.

[0088] Although, as depicted and described, the axially movable sealing ring 36 is stationary while the axially fixed sealing ring 30 is rotatable, in embodiments, relative axial movement may be provided by either the rotating or stationary sealing ring.

[0089] When used as a primary seal or a single seal, the optional channel 40 may be defined within the housing 18 and / or the sealing disc 20 to provide sealing lubricant (not shown) to the sealing surfaces 50 and 52. When used as a seal housing, the channel may be a vent such as the vent 90 described above.

[0090] The annular bellows or sealing membrane 100 may have a generally L-shaped cross-section, including a generally radially outwardly extending first flange portion 102 and a generally axially outwardly extending second coaxial portion 104. The flange portion 102 and the coaxial portion 104 may be operatively connected by a flexible connecting portion 106. The inner surface of the flange portion 102 may abut the outer surface of an axially movable sealing ring 36, thereby creating a pressure-tight seal. The coaxial portion 104 is substantially or entirely radially inward of the equilibrium diameter of the seal, where the pressure differential across the seal is greatest. The flexible connecting portion 106 may have an angled facet 108 radially inward and a connection angle θ between the flange portion 102 and the coaxial portion 104 radially outward. In an embodiment, the angle θ may be approximately ninety degrees, but other angles may also be used. The flexible connecting portion 106 may have a thinner cross-section than the flange portion 102 or the coaxial portion 104 to allow for stretching and compression.

[0091] Angled facet 108 may terminate at corner 110 in the radially inward extent of flexible connection portion 106. Facet 108 may have an angle between approximately 100° and approximately 150° relative to the axial axis. Sealing member 100 is non-shrinkable and may comprise a flexible material. Exemplary flexible materials include elastomers such as nitrile rubber, fluoroelastomers, and ethylene propylene rubber, but other materials may also be used.

[0092] The coaxial portion 104 can be secured to the annular stub sleeve 200 via an annular belt 300. The stub sleeve 200 has a first outer diameter D1, a second outer diameter D2, and an angled surface 112 connecting the first outer diameter to the second outer diameter. D2 is larger than D1. The radially outward-pointing surfaces of the stub sleeve 200 (D1, the angled surface 112, and D2) can respectively abut the coaxial portion 104, the small surface 108, and the axially movable sealing ring 36. Thus, in the event of a pressure peak, the stub sleeve 200 provides rigid support to the annular flexible sealing membrane 200, preventing it from collapsing in a gyroelastic manner as described above.

[0093] The short sleeve 200 may have a groove 202 to receive a retaining ring 204, thereby axially positioning the short sleeve relative to the carrier 504 (discussed below). The carrier 504 may, for example, be attached to... Figure 1The receiving sealing carrier 94. In an embodiment, the stub sleeve 200 may be radially positioned by a retaining ring 204, hydraulic pressure, or interference engagement with the carrier 504 (discussed below) or other components of the sealing assembly 10. In an embodiment, the stub sleeve 200, the belt 300, and the retaining ring 204 may comprise steel or stainless steel.

[0094] An annular anti-compression ring 400 may be present in the annular groove of the axially movable sealing ring 36 and adjacent to the axially movable sealing ring 36, the stub sleeve 200, and the sealing member 100. The annular anti-compression ring 400 may comprise an elastomer harder than the sealing membrane 100, such as carbon-filled polytetrafluoroethylene (PTFE) with a hardness of 50 to 55 (Shore D). Because compression is most likely to occur at the equilibrium diameter of the seal, the inner diameter of the anti-compression ring 400 may be arranged at the equilibrium diameter of the seal. As mentioned above, in some embodiments, this ring may be omitted. An example of such an embodiment is... Figure 1 The middle part is shown by the housing seal 3.

[0095] The biasing mechanism 500 may abut the flange portion 102. The biasing mechanism 500 may include an axially movable annular retainer 502, an axially fixed carrier 504, and one or more biasing members 506 spanning between them. The retainer 502 may be arranged close to the flange portion 102. The retainer 504 may have a protrusion 508 extending axially inwardly outside the outer diameter of the flange portion 102. The protrusion 508 may be radially spaced from the outer surface of the flange portion 102. The carrier 504 may be axially and rotatably secured to the cover plate 20 by one or more pins 510, but other securing mechanisms may also be used. The biasing members 506 may include one or more radially spaced springs, but other biasing mechanisms known in the art may also be used. In an embodiment, one or both of the retainer 502 and the carrier 504 may include holes adapted to receive at least a portion of each biasing member 506, such that the biasing member 506 is partially located within the retainer 502 and the carrier 504.

[0096] Those skilled in the art will understand that Figure 2 and 3 The arrangement shown includes components that can be changed or removed in other sealing assembly embodiments. Additionally, more or fewer components may be incorporated in other embodiments of the sealing assembly according to this disclosure.

[0097] In operation, rotation of shaft 12 drives sleeve member 22 and axially fixed sealing ring 30 to rotate relative to axially movable sealing ring 36. If used as a preferred seal, sealing lubricant can be supplied to seal 10 from chamber 14 or via optional channel 40 to lubricate sealing surfaces 50 and 52 and create a pressure gradient on sealing surfaces 50 and 52. When the sealing assembly is used as a housing for a seal or alone in a gaseous environment, surfaces 50, 52 may include, for example... Figure 6 and 7 The groove shown.

[0098] The pressure gradient and hydraulic pressure generated by the relative rotation of sealing surfaces 50 and 52 can produce an opening force, pushing the axially movable sealing ring 36 axially outward from the axially fixed sealing ring 30. Similarly, a closing force can be provided by the biasing mechanism 500, pushing the axially movable sealing ring 36 inward toward the axially fixed sealing ring 30.

[0099] Those skilled in the art will understand that the closing force at the sealing interface can be calculated from the closing area (AC), the opening area (AO), the outer diameter (OD) of the fixed annular surface, the inner diameter (ID) of the fixed annular surface, and the equilibrium diameter (BD), as detailed below:

[0100]

[0101] in,

[0102] The flange portion 102 can move axially and radially based on the relative closing and opening forces and the axial translation of the shaft itself, such that the closing force applied to the axially movable sealing ring 36 is constant and independent of the position of the flange portion 102.

[0103] Figure 4A and 4B This is a detailed view of an embodiment of the sealing assembly, showing some of the effects of axial movement on the sealing membrane 100. Axial outward translation of the shaft can be transmitted to the flange portion 102 via the sleeve 22, the axially retaining ring 30, and the axially movable sealing ring 36. This movement can slightly compress and angularly deform the flange portion 102, preventing any changes in the opening and closing forces at the sealing interface. Specifically, as shown, axial outward translation of the axially movable sealing ring 36 can transmit the opening force to the flange portion 102, resulting in axial outward and radial outward translation of the flange portion 102 away from the stub sleeve 200, such as... Figure 4A As shown. Conversely, the axial inward translation of shaft 12 relieves the pressure on flange portion 102, thereby allowing flange portion 102 to translate axially and radially inward against stub sleeve 200. This contact between the sealing membrane and stub sleeve 200 further minimizes leakage.

[0104] The high pressure gradient on sealing surfaces 50 and 52 can promote partial compression of the flexible sealing membrane 100 between the stub sleeve 200 and the axially movable sealing ring 36. This can be resisted by the harder material of the anti-compression ring 400.

[0105] When used without a grooved surface (e.g., as the main seal 2 above), sealing surfaces 50 and 52 will wear relative to each other during the seal's lifespan. Because the sealing membrane 100 can move inward toward the chamber 14 and outward away from the chamber 14 during the seal's lifespan, it helps maintain a proper sealing clearance. Hydraulic pressure prevents the axially movable sealing ring 36 from contacting the axially fixed sealing ring 30 while the flange portion 102 of the sealing membrane 100 moves inward. Hydraulic pressure can hold other components, such as the stub sleeve 200, in place. Furthermore, because the coaxial portion 104 is below the seal's balance diameter, hydraulic pressure applied to the coaxial portion 104 will not affect the closing force or the balance diameter itself. When no hydraulic pressure is present, the biasing mechanism 500 can be used to set the working height of the seal and press the flange portion 102 of the sealing membrane 100 against the end of the axially movable sealing ring 36 (relative to the distal end of the processing chamber and the opposing sealing surface 52) (forming a seal). Because the vertical force is not altered by the axial movement of the sealing membrane 100, and the closing force at the interface of the sealing surfaces 50 and 52 is unaffected.

[0106] When used as a dry-run containment seal, the faces do not contact (or have very little contact), so the seal does not degrade over time and is essentially new in the event of failure of the main seal.

[0107] The maximum axial outward translation of the flange portion 102 and the retainer 502 may be limited by the gap provided between the outer surface of the retainer 502 and the inner surface of the carrier 504, or by the compression limit of the biasing member 506. In embodiments, the translation of the flange portion 102 may be restricted to prevent the sealing member 100 from bunching, folding, or other collapse at the connection portion 106. In one embodiment, the translation of the flange portion 102 may be restricted to a retention angle θ or φ.

[0108] Furthermore, because the flange portion 102 is held in a radially extending position by the axially movable sealing ring 36 and retainer 502, and the coaxial portion 104 is held in an axially extending position by the short sleeve 200 and belt 300, the sealing member 100 is non-collapseable.

[0109] like Figure 5As shown, the angle θ between the flange portion 102 and the coaxial portion 104 of the sealing membrane 100 provides directional control of the forces acting on the short sleeve 200 and the axially movable sealing ring 36. When the flange portion 102 is under pressure at the equilibrium diameter of the seal, the coaxial portion 104 allows the flange portion 102 and the connecting portion 106 to be flexible.

[0110] Now for reference Figure 8 Another embodiment is shown. In this embodiment, a sealing assembly 800 is shown, which includes two seals, both of which include annular flexible sealing membranes. The main seal 802 in this embodiment is related to the one described above. Figure 2-5 The seals are substantially the same and include an optional compression ring 400. The secondary seal 3 is similar to... Figure 1 The secondary seals mentioned above are the same.

[0111] like Figure 8 As shown, the sealing assembly 800 is adapted to be arranged around a rotating shaft 12. This shaft can be the shaft of a pump or any other type of rotating machinery. The assembly 800 includes a first or main seal 802 and a second or receiving seal 3. The first seal 802 includes a first main ring 136 and a first mating ring 130, which respectively include sealing surfaces 152 and 150. The first main ring 136 is axially movable relative to the rotating shaft 12, and the first mating ring 130 is axially fixed relative to the rotating shaft 12.

[0112] The main seal 802 includes a first biasing mechanism 1500 that pushes the first main ring 136 toward the first mating ring 150. The main seal 802 also includes a first annular flexible sealing membrane 1100 having a first flange portion 1102 at least partially disposed between the first biasing mechanism 1500 and the first main ring 136, a first coaxial portion 1104 axially fixable relative to the shaft 12, and a first flexible connecting portion 106 positioned radially inward of the first flange portion 1102 and connecting the first flange portion 1102 to the first coaxial portion 1104. In operation, a liquid film is formed between the first main ring 136 and the first mating ring 130. In one embodiment, the film is formed by liquid in a chamber 7, which in one embodiment may be in a pump. As described above, in some cases (e.g., light fractions), the liquid in the liquid film will generate gas as it moves through the seal 802 (e.g., between surfaces 150, 152). The gas enters the receiving cavity 63, which is formed between the main seal 802 and the receiving seal 3.

[0113] The operation of accommodating seal 3 is as described above. Figure 1The following description is provided, and reference is made thereto. In one embodiment, the receiving seal may be referred to as the second seal and is in fluid communication with the receiving cavity 63. The second seal 3 includes a second main ring 36 and a second mating ring 30. The second main ring 36 is axially movable relative to the rotation shaft 12, and the second mating ring 30 is axially fixed relative to the rotation shaft 12. The second seal 3 also includes a second biasing mechanism 500 that pushes the second main ring 36 toward the second mating ring 30, the second main ring 36 including a face 3', and the second mating ring including a face 30'. The second seal includes a second annular flexible sealing membrane 100, which includes: a second flange portion 102 that is at least partially disposed between the second biasing mechanism 500 and the second main ring 36; a second coaxial portion 104 that is axially fixed relative to the shaft 12; and a second flexible connecting portion 106 that is positioned radially inward of the second flange portion 102 and connects the second flange portion 102 to the second coaxial portion 104. In this embodiment, at least one of the second mating ring 30 and the second main ring 36 includes a groove formed on its surface, which causes a gas film to form between the second main ring 36 and the second mating ring 36. This gas film is formed by gas in the receiving cavity 63 during normal operation. This gas is at least partially derived from gas in the receiving cavity that passes through the first seal 802. During normal operation, the gas film prevents the second main ring and the second mating ring from contacting each other.

[0114] As shown in the figure, similar to the above. Figure 1 The sealing assembly 800 is disposed in the hole 6 formed in the annular housing 18. More specifically, the annular sleeve member 22 is fixedly attached to the shaft 12 and rotates with it. Figure 8 In the example shown, with respect to the main seal 802, the first or main ring 136 is carried on the annular sleeve 22, and the second or matching ring 130 is carried by the carrier ring 92, which is fixedly attached to the annular housing 18 during operation.

[0115] As described above, the receiving sealing carrier 94 carries the main ring 36 of the secondary sealing element 3, as well as the short sleeve 200, the biasing mechanism 500, and the annular flexible sealing membrane 100.

[0116] In this and other embodiments, the receiving sealing carrier 94 and the carrier ring 92 may be connected together to form a cylinder. In this and other embodiments, the cylinder thus formed may be connected to the annular housing 18. In some cases, the cylinder may include an end plate 17 connecting the receiving sealing carrier 94 to the annular sleeve component 22. In one embodiment, the cylinder may define a receiving cavity 23.

[0117] Various embodiments of the invention are described herein with reference to the accompanying drawings. Alternative embodiments of the invention may be devised without departing from the scope thereof. In the following description and drawings, various connections and positional relationships (e.g., above, below, adjacent, etc.) are illustrated between elements. Unless otherwise stated, these connections and / or positional relationships may be direct or indirect, and the invention is not intended to be limiting in this respect. Therefore, the connection of entities may refer to direct or indirect connection, and the positional relationship between entities may be direct or indirect positional relationship. Furthermore, the various tasks and process steps described herein may be incorporated into a more comprehensive procedure or process with additional steps or functionality not described in detail herein.

[0118] The term “about” is intended to include the degree of error associated with measurements based on a specific quantity of equipment available at the time of filing this application.

[0119] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the terms “comprising” and / or “including” as used in this specification specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0120] Although this disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and elements can be substituted with equivalents without departing from the scope of this disclosure. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of this invention without departing from the essential scope of the invention. Therefore, this disclosure is not limited to the specific embodiments disclosed as the best mode for carrying out this disclosure, but rather this disclosure will include all embodiments falling within the scope of the claims.

Claims

1. A mechanical seal assembly adapted to be arranged about a rotating shaft of a pump, the seal assembly comprising: A first seal, comprising: A first main ring and a first matching ring, wherein the first main ring is axially displaceable relative to the rotation axis, and the first matching ring is axially fixed relative to the rotation axis; A first biasing mechanism, which pushes the first main ring toward the first matching ring; and A first annular flexible sealing membrane, comprising: The first flange portion is at least partially disposed between the first biasing mechanism and the first main ring; A first coaxial portion, the first coaxial portion being axially fixed relative to the shaft; and A first flexible connection portion is located within the radially inward range of the first flange portion and connects the first flange portion to the first coaxial portion; In operation, a liquid film is formed between the first main ring and the first mating ring by a first liquid within the pump. After passing through the first seal, the first liquid in the liquid film generates a gaseous form of the first liquid, which is then supplied to the receiving cavity. A second seal that is in fluid communication with the receiving cavity, the second seal comprising: A second main ring and a second matching ring, wherein the second main ring is axially displaceable relative to the rotation axis and the second matching ring is axially fixed relative to the rotation axis; The second biasing mechanism pushes the second main ring toward the second matching ring; and A second annular flexible sealing membrane, the second annular flexible sealing membrane comprising: The second flange portion is at least partially disposed between the second biasing mechanism and the second main ring; A second coaxial portion, the second coaxial portion being axially fixed relative to the shaft; and The second flexible connection portion is located within the radially inward range of the second flange portion and connects the second flange portion to the second coaxial portion; At least one of the second mating ring and the second main ring includes a groove formed on its surface, the groove causing an air film to form between the second main ring and the second mating ring, the air film being at least partially formed by gas passing through the first seal in the receiving cavity, the air film preventing the second main ring and the second mating ring from contacting each other during operation.

2. The component according to claim 1, wherein the liquid is a light fraction with a specific gravity of less than 0.

7.

3. The component according to claim 2, wherein, The liquid is propane, butane, gasoline, or naphtha.

4. The component according to claim 1, wherein, The groove is a unidirectional groove.

5. The component according to claim 1, wherein, The groove is a bidirectional groove.

6. The component of claim 1, wherein the first seal and the second seal are disposed in the cylinder.

7. The component according to claim 6, wherein, The cylinder is at least partially disposed within the pump.

8. The component according to claim 6, wherein, The second seal is in fluid communication with the first seal inside the cylinder.

9. The component according to claim 1, wherein, The second coaxial portion can be arranged with a diameter within the balance diameter of the sealing assembly.

10. The component of claim 1, wherein, During operation, the axial translation of the rotating shaft relative to the second biasing mechanism causes the second flange portion to shift axially and radially inward relative to the second coaxial portion.

11. The component of claim 1, wherein, During operation, the axial translation of the rotating shaft relative to the second biasing mechanism causes the second flange portion to be axially and radially displaced relative to the second coaxial portion.

12. The component according to claim 1, wherein, The second flexible connection portion has a thinner cross-section than the second flange portion and the second coaxial portion.

13. The component according to claim 1, characterized in that, The component also includes an anti-crushing ring that can be received within a groove in the first main ring.

14. The component of claim 1, further comprising a rotary sleeve operably coupled to the rotary shaft for rotation with the rotary shaft, wherein the first mating ring and the second mating ring are operably coupled to the rotary sleeve.

15. The component of claim 1, wherein the first annular flexible sealing membrane and the second annular flexible sealing membrane comprise a flexible elastomer.

16. A mechanical seal assembly adapted to be arranged about a rotating shaft of a pump, the seal assembly comprising: A first seal, comprising: First main ring; The first matching ring; and A first biasing mechanism pushes the first main ring toward the first matching ring; In operation, a liquid film is formed between the first main ring and the first mating ring by a first liquid within the pump. After passing through the first seal, the first liquid in the liquid film generates a gaseous form of the first liquid, which is then supplied to the receiving cavity. A second seal that is in fluid communication with the receiving cavity, the second seal comprising: A second main ring and a second matching ring, wherein the second main ring is axially displaceable relative to the rotation axis and the second matching ring is axially fixed relative to the rotation axis; A second biasing mechanism pushes the second main ring toward the second matching ring; and A second annular flexible sealing membrane, the second annular flexible sealing membrane comprising: The second flange portion is at least partially disposed between the first biasing mechanism and the first main ring; A second coaxial portion, the second coaxial portion being axially fixed relative to the shaft; and The second flexible connection portion is located within the radially inward range of the second flange portion and connects the second flange portion to the second coaxial portion; At least one of the second mating ring and the second main ring includes a groove formed on its surface, the groove causing a gas film to be formed by gas in the receiving cavity, the gas film passing through the first seal to form between the second main ring and the second mating ring, the gas film preventing the second main ring and the second mating ring from contacting each other during operation.

17. The component of claim 16, wherein the liquid is a light end.

18. The component of claim 17, wherein, The liquid is propane, butane, gasoline, or naphtha.

19. The component of claim 16, wherein, The groove is a unidirectional groove.

20. The component of claim 16, wherein, The groove is a bidirectional groove.

21. The component of claim 16, wherein, The first seal and the second seal are disposed inside the cylinder.

22. The component of claim 21, wherein, The cylinder is at least partially disposed within the pump.

23. The component of claim 21, wherein, The second seal is in fluid communication with the first seal inside the cylinder.

24. The component of claim 16, wherein, The second coaxial portion can be arranged with a diameter within the balance diameter of the sealing assembly.

25. The component of claim 16, wherein, During operation, the axial translation of the rotating shaft relative to the second biasing mechanism causes the second flange portion to shift axially and radially inward relative to the second coaxial portion.

26. The component of claim 16, wherein, During operation, the axial translation of the rotating shaft relative to the second biasing mechanism causes the second flange portion to shift axially and radially outward relative to the second coaxial portion.

27. The component of claim 16, wherein, The second flexible connection portion has a thinner cross-section than the second flange portion and the second coaxial portion.

28. The component of claim 16, further comprising a rotary sleeve operably coupled to the rotation shaft for rotation with the rotation shaft, and wherein the second mating ring is operably coupled to the rotary sleeve.

29. The component of claim 16, wherein, The second annular flexible sealing membrane includes a flexible elastomer.

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