CN117231754A - Butterfly valve with self-compensating seal assembly - Google Patents
Butterfly valve with self-compensating seal assembly Download PDFInfo
- Publication number
- CN117231754A CN117231754A CN202311423860.1A CN202311423860A CN117231754A CN 117231754 A CN117231754 A CN 117231754A CN 202311423860 A CN202311423860 A CN 202311423860A CN 117231754 A CN117231754 A CN 117231754A
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- ring
- self
- groove
- seal assembly
- butterfly
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- 238000007789 sealing Methods 0.000 claims abstract description 61
- 238000003825 pressing Methods 0.000 claims abstract description 23
- 239000002131 composite material Substances 0.000 claims abstract description 17
- 229920001973 fluoroelastomer Polymers 0.000 claims description 3
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 3
- -1 polytetrafluoroethylene Polymers 0.000 claims description 2
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 2
- 239000012530 fluid Substances 0.000 abstract description 17
- 230000002457 bidirectional effect Effects 0.000 abstract description 4
- 230000000149 penetrating effect Effects 0.000 abstract description 2
- 238000005260 corrosion Methods 0.000 description 7
- 230000007797 corrosion Effects 0.000 description 7
- 238000000034 method Methods 0.000 description 7
- 239000000126 substance Substances 0.000 description 7
- 239000007788 liquid Substances 0.000 description 6
- 239000002253 acid Substances 0.000 description 4
- 230000005284 excitation Effects 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 230000002378 acidificating effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 229920002449 FKM Polymers 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 239000003209 petroleum derivative Substances 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Abstract
The present invention provides a butterfly valve provided with a self-compensating seal assembly, comprising: the composite valve seat is a hollow ring body and comprises a valve body and a pressing plate which are connected through assembly; the toothed grooves are arranged on the inner side surface of the composite valve seat, are arranged along the circumferential direction of the joint of the valve body and the pressing plate and are used for installing the sealing assembly; a valve shaft vertically penetrating the composite valve seat; the butterfly plate is sleeved on the valve shaft, rotates under the drive of the valve shaft, and is in interference fit with the sealing component on the composite valve seat, so that the conduction or the disconnection of the pipeline is controlled. The sealing assembly is excited by the pressure of the fluid medium to realize the tightness of the sealing assembly, and when the temperature changes and the contact surface of the sealing ring is worn, the butterfly valve sealing assembly with self-adjusting capability can perform self-compensation, thereby realizing the functions of long service life, zero leakage and bidirectional sealing under extremely complex working conditions.
Description
Technical Field
The invention belongs to the field of valves, and particularly relates to a butterfly valve with a self-compensating sealing component.
Background
With the development of various industries such as aerospace, navigation, petrochemical industry and the like, the demands of butterfly valves for effective and reliable operation under some extremely complex working conditions (ultralow temperature, ultrahigh temperature, high pressure, corrosion or acidic multiphase flow and the like) are becoming more apparent. The soft seal assembly of the butterfly valve may provide bi-directional complete sealing and flow control of single phase fluid (gas or liquid) and multiphase fluid (solid-liquid, solid-gas, liquid-gas, or solid-liquid-gas systems) media under chemical corrosion or acidic conditions. For example, oil tankers are specialized vessels designed for high efficiency delivery of oil and petroleum products in large volumes, and their reliance on high performance butterfly valves under chemical conditions is significant. Meanwhile, the petroleum and other chemicals have the characteristics of combustibility, explosiveness, strong corrosiveness and the like, so the high-performance butterfly valve is frequently used in the system. Therefore, the high-performance butterfly valve can still normally and effectively play a role under the complex mixed working conditions of strong corrosion, normal medium temperature, low medium high pressure, vibration and the like, and has extremely high practical significance and economic value.
Disclosure of Invention
The butterfly valve with the self-compensating sealing component has the advantages that the butterfly valve with the self-compensating sealing component is high in robustness, the sealing performance of the sealing component is excited through fluid medium pressure, and when the temperature changes and the contact surface of a sealing ring is worn, the butterfly valve sealing component with the self-adjusting capability can perform self-compensation, so that the functions of long service life, zero leakage and bidirectional sealing under extremely complex working conditions are realized.
To achieve the above object, the present invention provides a butterfly valve provided with a self-compensating seal assembly, comprising: the composite valve seat is a hollow ring body and comprises a valve body and a pressing plate which are connected through assembly; the toothed grooves are arranged on the inner side surface of the composite valve seat, are arranged along the circumferential direction of the joint of the valve body and the pressing plate and are used for installing the sealing assembly; a valve shaft vertically penetrating the composite valve seat; the butterfly plate is sleeved on the valve shaft, rotates under the drive of the valve shaft, and is in interference fit with the sealing component on the composite valve seat, so that the conduction or the disconnection of the pipeline is controlled.
Preferably, the toothed groove is formed by a first groove arranged along the circumference of a first connecting surface of the valve body, which is in contact with the pressing plate, and a second groove arranged along the circumference of a second connecting surface of the pressing plate, which is in contact with the valve body.
Preferably, the toothed groove is formed by arranging the first groove opposite to the second connecting surface of the pressing plate without the second groove; or the second groove is arranged opposite to the first connecting surface of the valve body without the first groove.
Preferably, the diameter of the inner diameter end of the first groove is larger than the diameter of the outer diameter end, and a plurality of first tooth-shaped protrusions are arranged on the first connecting surface of the outer diameter end.
Preferably, the diameter of the inner diameter end of the second groove is larger than the diameter of the outer diameter end, and a plurality of second tooth-shaped protrusions are arranged on the second connecting surface of the outer diameter end.
Preferably, the sealing assembly comprises a sealing ring, the inner diameter end of the sealing ring is provided with a hollow circular ring with an accommodating space, and the section shape of the outer diameter end is rectangular.
Preferably, an inner lining ring is arranged in the hollow circular ring; the inner lining ring is used as an elastic energizing ring and is wrapped by a hollow circular ring at the inner diameter end of the sealing ring.
Preferably, the inner diameter end and the outer diameter end of the sealing ring are respectively and correspondingly arranged at the inner diameter end and the outer diameter end of the toothed groove, and the outer diameter end of the sealing ring is extruded by the valve body and the pressing plate to form interference fit.
Preferably, the first tooth-shaped protrusions and the second tooth-shaped protrusions are arranged in a one-to-one correspondence manner; or the first toothed protrusion and the second toothed protrusion are arranged in a staggered manner.
Preferably, the sealing ring is made of polytetrafluoroethylene, and the inner liner is made of fluororubber.
In summary, compared with the prior art, the butterfly valve provided by the invention has the following beneficial effects:
(1) The method has higher robustness to chemical corrosion or acid working condition, high cycle low-medium cycle fatigue failure;
(2) The sealing component can provide excellent elastic performance through excitation of fluid medium pressure, improves the sealing performance of the butterfly valve, expands the application range, and can be applied to chemical corrosion or acid working conditions, single-phase fluid (gas or liquid) and multiphase fluid (solid-liquid, solid-gas, liquid-gas or solid-liquid-gas systems) or other similar products;
(3) The sealing assembly formed by the sealing ring and the inner lining ring has the function of storing and releasing elastic energy, and the sealing ring and the toothed groove form an annular plate spring structure, so that the butterfly valve has the advantages of self-compensating positive feedback, fatigue resistance and long service life;
(4) The sealing structure is simple, the installation, the debugging, the maintenance and the maintenance are easy, and the robustness of the whole structure is high.
Drawings
FIG. 1 is a schematic view of a butterfly valve provided with a self-compensating seal assembly in accordance with the present invention;
FIG. 2 is a schematic partial cross-sectional view of a butterfly valve provided with a self-compensating seal assembly in accordance with the invention.
Detailed Description
The technical scheme, constructional features, achieved objects and effects of the embodiments of the present invention will be described in detail below with reference to fig. 1 to 2 in the embodiments of the present invention.
It should be noted that, the drawings are in very simplified form and all use non-precise proportions, which are only used for the purpose of conveniently and clearly assisting in describing the embodiments of the present invention, and are not intended to limit the implementation conditions of the present invention, so that the present invention has no technical significance, and any modification of structure, change of proportion or adjustment of size, without affecting the efficacy and achievement of the present invention, should still fall within the scope covered by the technical content disclosed by the present invention.
It is noted that in the present invention, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
The present invention provides a butterfly valve provided with a self-compensating seal assembly for controlling the on-off of a fluid delivery line, as shown in fig. 1 and 2, the butterfly valve comprising: a composite valve seat 100, which is a ring body having a hollow interior, including a valve body 101 and a pressing plate 102 connected by assembly; a tooth-shaped groove 103 provided on the inner side surface of the composite valve seat 100 and provided along the circumferential direction of the joint between the valve body 101 and the pressure plate 102 for mounting the seal assembly 200; a valve shaft 300 vertically disposed through the composite valve seat 100; the butterfly plate 400 is sleeved on the valve shaft 300, the butterfly plate 400 rotates under the drive of the valve shaft 300 and is in interference fit with the sealing assembly 200 on the composite valve seat 100, and the conduction or the disconnection of a pipeline is controlled.
Specifically, in the present embodiment, as shown in fig. 2, the tooth-like groove 103 is formed by opposing a first groove 111 provided circumferentially along a first connection surface of the valve body 101 in contact with the pressing plate 102 and a second groove 121 provided circumferentially along a second connection surface of the pressing plate 102 in contact with the valve body 101. Specifically, the first groove 111 of the valve body 101 faces the second groove 121 of the pressing plate 102, and then the valve body 101 and the pressing plate 102 are fixed by using bolts, so that the first connecting surface of the valve body 101 contacts the second connecting surface of the pressing plate 102, and the first groove 111 and the second groove 121 form the toothed groove 103.
Wherein, the diameter of the inner diameter end (i.e. the end close to the butterfly plate 300) of the first groove 111 is larger than the diameter of the outer diameter end (i.e. the end far from the butterfly plate 300), and a plurality of first tooth-shaped protrusions 112 (3 in the embodiment) are arranged on the first connection surface of the outer diameter end; likewise, the diameter of the inner diameter end of the second groove 121 is larger than the diameter of the outer diameter end, and a plurality of second tooth-shaped protrusions 122 are arranged on the second connection surface of the outer diameter end; in the present embodiment, the first tooth-shaped protrusions 112 are disposed in one-to-one correspondence with the second tooth-shaped protrusions 122; in other embodiments, the first and second teeth protrusions 112 and 122 may be offset. In yet another embodiment, the toothed groove 103 may be formed by a groove in combination with a planar connection surface; specifically, the toothed groove 103 is formed by arranging the first groove 111 opposite to the second connecting surface of the pressing plate 102 where the second groove 121 is not arranged; or by the second groove 121 being disposed opposite to the first connection surface of the valve body 101 where the first groove 111 is not disposed.
In this embodiment, as shown in fig. 2, the seal assembly 200 is installed in a toothed groove 103 formed by the valve body 101 and the pressing plate 102, where there is an interference fit between the seal assembly 200 and the toothed groove 103, and also there is an interference fit between the butterfly plate 400, and by controlling the interference between the seal assembly 200 and the toothed groove 103, the interference between the seal assembly 200 and the butterfly plate 400 can be adjusted, so as to further improve the sealing performance of the butterfly valve.
Further, as shown in fig. 2, the sealing assembly 200 includes a sealing ring 201, an inner diameter end (i.e., an end contacting the butterfly plate 300) of which is provided with a hollow circular ring 211 having a receiving space, and an outer diameter end (i.e., an end disposed opposite to the inner diameter end) of which has a rectangular cross-sectional shape; the inner diameter end and the outer diameter end of the sealing ring 201 are respectively and correspondingly arranged at the inner diameter end and the outer diameter end of the toothed groove 103, and the outer diameter end of the sealing ring 201 is extruded by the valve body 101 and the pressing plate 102 to form interference fit. Wherein, a lining ring 212 is arranged in the hollow circular ring 211; the inner ring 212 is used as an elastic energizing ring and is wrapped by a hollow circular ring 211 at the inner diameter end of the sealing ring 201, so as to form the sealing assembly 200. The seal 201 provided with the inner liner 212 is activated by fluid medium pressure, and the elasticity of the inner liner 212 is increased along with the increase of the fluid medium pressure in the effective working range, so that the long-service life zero-leakage bidirectional seal is provided. Alternatively, the seal ring 201 is made of polytetrafluoroethylene (Teflon), and the inner ring 212 is made of highly elastic, high temperature resistant fluororubber (Viton).
When the butterfly valve works, the outer diameter end of the sealing ring 201 and the toothed groove 103 form interference fit, so that the interference of effective sealing between the inner diameter end of the sealing ring 201 and the butterfly plate 400 can be controlled. Further, since the inner liner ring 212 is wrapped in the hollow circular ring 211 by the sealing ring 201 as an elastic energizing ring, effective and reliable elastic force is provided for the composite valve seat 100, when the sealing ring 201 and the butterfly plate 400 are in interference fit (i.e. the butterfly valve is in a pipeline cutting state), the butterfly plate 400 compresses the sealing ring 201 radially outwards, and the inner liner ring 212 can absorb the compression energy and ensure that the sealing ring 201 cannot be crushed, so that the self-compensating function of the sealing assembly 200 is realized. The inner diameter end of the seal ring 201 is in interference fit with the butterfly plate 400, and the seal function is achieved through the high elasticity provided by the inner lining ring 212.
Still further, the toothed groove 103 formed between the valve body 101 and the pressing plate 102 tightly engages with the outer diameter end of the sealing ring 201 through interference fit to realize sealing, and on the other hand, under the excitation of the fluid medium pressure, the engagement between the toothed groove 103 on the other side of the arrival direction of the fluid medium pressure and the outer diameter end of the sealing ring 201 is enhanced, so that the tightness is improved, and the zero-leakage bidirectional sealing is realized. For different calibers, pressure levels and actual temperatures, the interference between the outer diameter end of the sealing ring 201 and the toothed groove 103 and the interference between the inner diameter end of the sealing ring 201 and the butterfly plate 400 need to be adjusted according to actual conditions. For example, the pressure level is high, and the interference magnitude needs to be correspondingly improved. In the normal opening and closing process of the butterfly plate 400, the seal ring 201 can undergo a tight-loose-tight alternating cyclic load, and the high-elasticity inner liner 212 can absorb and release energy in the process, so that fatigue failure in low cycle and medium cycle is avoided, and long-life sealing performance of the butterfly valve is realized.
When the butterfly valve provided with the self-compensating seal assembly according to the present embodiment operates normally for a long time, the inner diameter end (i.e. the end provided with the hollow ring) of the seal ring 201 and the butterfly plate 400 may wear to some extent, and the liner ring 212 can release the stored energy to force the inner diameter end of the seal ring 201 to deform in a direction close to the butterfly plate 400. In addition, the seal ring 201 and the toothed groove 103 formed between the valve body 101 and the pressing plate 102 form an annular plate spring structure, specifically, the inner diameter end of the seal ring 201 is a movable end of the annular plate spring, and the outer diameter end (i.e. a plane end) of the seal ring 201 is a fixed end of the annular plate spring. When the seal ring 201 or the butterfly plate 400 is worn greatly, the inner diameter end of the seal ring 201 moves towards the pressure direction of the fluid medium through the energy storage of the annular plate spring structure under the excitation of the pressure of the fluid medium, and then the seal structure with the self-compensating positive feedback function is realized by virtue of the two points of the elastic energizing ring (namely the lining ring 212) and the annular plate spring structure.
In addition, the butterfly valve provided with the self-compensating seal assembly provided by the embodiment is also easy to repair and maintain. Even when the inner diameter end of the seal ring 201 and the butterfly plate 400 are worn particularly severely, the seal assembly can be rapidly repaired and maintained without being compensated for sealing performance by the self-compensating positive feedback function. For example, when the seal ring 201 is severely damaged, the seal assembly 200 formed by the seal ring 201 and the inner liner 212 is simply removed and replaced. For example, when the seal ring 201 is worn seriously, the gap between the valve body 101 and the pressing plate 102 can be adjusted slightly to realize quick maintenance.
In summary, compared with the existing butterfly valve, the butterfly valve provided by the invention has higher robustness to chemical corrosion or acid working conditions, high-cycle low-middle cycle fatigue failure, and the sealing assembly 200 can provide excellent elastic performance through excitation of fluid medium pressure, so that the sealing performance of the butterfly valve is improved, the application range is enlarged, and the butterfly valve can be applied to chemical corrosion or acid working conditions, single-phase fluid (gas or liquid) and multiphase fluid (solid-liquid, solid-gas, liquid-gas, or solid-liquid-gas systems) or other similar products; secondly, the seal assembly 200 formed by the seal ring 201 and the inner lining ring 212 has the function of storing and releasing elastic energy, and the seal ring 201 and the toothed groove 103 form an annular plate spring structure, so that the butterfly valve has the advantages of self-compensating positive feedback, fatigue resistance and long service life.
While the present invention has been described in detail through the foregoing description of the preferred embodiment, it should be understood that the foregoing description is not to be considered as limiting the invention. Many modifications and substitutions of the present invention will become apparent to those of ordinary skill in the art upon reading the foregoing. Accordingly, the scope of the invention should be limited only by the attached claims.
Claims (10)
1. A butterfly valve provided with a self-compensating seal assembly, comprising:
a composite valve seat (100) which is a ring body with a hollow interior and comprises a valve body (101) and a pressing plate (102) which are connected through assembly;
a tooth-shaped groove (103) which is arranged on the inner side surface of the composite valve seat (100), is arranged along the circumferential direction of the joint of the valve body (101) and the pressing plate (102), and is used for installing a sealing assembly (200);
a valve shaft (300) that is disposed vertically through the composite valve seat (100);
the butterfly plate (400) is sleeved on the valve shaft (300), the butterfly plate (400) rotates under the drive of the valve shaft (300) and is in interference fit with the sealing assembly (200) on the composite valve seat (100), and the conduction or the disconnection of a pipeline is controlled.
2. Butterfly valve provided with a self-compensating seal assembly according to claim 1, wherein the toothed groove (103) is formed by a first groove (111) arranged circumferentially along a first connection face of the valve body (101) in contact with the pressure plate (102) and a second groove (121) arranged circumferentially along a second connection face of the pressure plate (102) in contact with the valve body (101) being arranged opposite each other.
3. Butterfly valve provided with a self-compensating seal assembly according to claim 1, wherein the toothed groove (103) is formed by a first groove (111) arranged opposite a second connection face of the pressure plate (102) where no second groove (121) is arranged; or the second groove (121) is arranged opposite to the first connecting surface of the valve body (101) without the first groove (111).
4. A butterfly valve provided with a self-compensating seal assembly according to claim 2, wherein the first groove (111) has an inner diameter larger than an outer diameter, and the first connection surface of the outer diameter is provided with a plurality of first teeth-like protrusions (112).
5. Butterfly valve provided with a self-compensating seal assembly according to claim 2 or 4, characterized in that the second groove (121) has an inner diameter larger than an outer diameter, and that the second connection surface of the outer diameter is provided with a number of second toothed protrusions (122).
6. The butterfly valve provided with a self-compensating seal assembly according to claim 1, wherein the seal assembly (200) comprises a seal ring (201), the inner diameter end of the seal ring (201) is provided with a hollow circular ring (211) having a receiving space, and the outer diameter end has a rectangular cross-sectional shape.
7. The butterfly valve provided with a self-compensating seal assembly of claim 6, wherein a liner ring (212) is provided within the hollow ring (211); the inner lining ring (212) is used as an elastic energizing ring and is wrapped by a hollow circular ring (211) at the inner diameter end of the sealing ring (201).
8. The butterfly valve provided with the self-compensating seal assembly according to claim 6, wherein the inner diameter end and the outer diameter end of the seal ring (201) are respectively and correspondingly arranged at the inner diameter end and the outer diameter end of the tooth-shaped groove (103), and the outer diameter end of the seal ring (201) is extruded by the valve body (101) and the pressing plate (102) to form interference fit.
9. The butterfly valve provided with a self-compensating seal assembly of claim 5, wherein the first and second toothed protrusions (112, 122) are disposed in one-to-one correspondence; or the first toothed protrusion (112) and the second toothed protrusion (122) are arranged in a staggered manner.
10. Butterfly valve provided with a self-compensating seal assembly according to claim 7, wherein the sealing ring (201) is made of polytetrafluoroethylene and the inner ring (212) is made of fluororubber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311423860.1A CN117231754A (en) | 2023-10-30 | 2023-10-30 | Butterfly valve with self-compensating seal assembly |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311423860.1A CN117231754A (en) | 2023-10-30 | 2023-10-30 | Butterfly valve with self-compensating seal assembly |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117231754A true CN117231754A (en) | 2023-12-15 |
Family
ID=89089516
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311423860.1A Pending CN117231754A (en) | 2023-10-30 | 2023-10-30 | Butterfly valve with self-compensating seal assembly |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117231754A (en) |
-
2023
- 2023-10-30 CN CN202311423860.1A patent/CN117231754A/en active Pending
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