Pneumatic piston type double-eccentric high-performance butterfly valve

Abstract

The invention relates to the technical field of nitrogen and oxygen production through air separation, in particular to a pneumatic piston type double-eccentric high-performance butterfly valve which comprises a valve body, a rotating shaft and a butterfly plate. A limiting structure for limiting the reciprocating alternate movement stroke of the valve seat sealing ring between the sealing position and the sealing cancelling position is arranged between the valve seat assembly and the valve body, and when the limiting structure is located at the sealing position, the first inclined face and the second inclined face are sealed in a matched mode. A packing cavity is formed between the top of the valve body and the rotating shaft, and a self-tightening sealing packing assembly which is pressed by a packing gland and forms self-tightening sealing with the outer wall of the rotating shaft is arranged in the packing cavity. The valve seat assembly is pneumatically driven to do linear motion in the axial direction of the medium channel of the valve body, the position of the valve seat assembly is accurately controlled, friction between a valve seat sealing ring and a butterfly plate sealing face in the rotating process is avoided, and the service life of the valve seat sealing ring is prolonged. And meanwhile, high-efficiency, high-precision and safe control on the medium is realized.

Description

Technical Field

[0001] This invention relates to the field of air separation nitrogen and oxygen production technology, and more specifically, to a pneumatic piston-type double eccentric high-performance butterfly valve. Background Technology

[0002] Pressure swing adsorption (PSA) air separation systems for oxygen and nitrogen production utilize the selective adsorption capacity of adsorbents (such as carbon molecular sieves or molecular sieves) for different gas components to achieve gas separation under pressure variations. For example, in nitrogen production, compressed air enters the adsorption tower, where the carbon molecular sieve preferentially adsorbs oxygen, carbon dioxide, and moisture, enriching the nitrogen phase. When the adsorbent approaches saturation, desorption and regeneration are achieved through pressure reduction or vacuuming, thus enabling continuous nitrogen production. Frequent valve operation is required to achieve the periodic switching of the adsorption tower (adsorption-desorption cycle).

[0003] Pressure swing adsorption (PSA) air separation systems for oxygen and nitrogen production extensively utilize double-eccentric high-performance butterfly valves. These valves operate at extremely high frequencies, requiring opening and closing every two minutes. Existing conventional valves cannot meet these high-frequency switching requirements, leading to wear and leakage of the valve seat seals and severely impacting PSA efficiency. Summary of the Invention

[0004] In view of this, the present invention proposes a pneumatic piston-type double eccentric high-performance butterfly valve, which aims to solve the problem of easy wear and leakage of the valve seat sealing ring under the condition of high-frequency valve switching in the current technology.

[0005] This invention proposes a pneumatic piston-type double eccentric high-performance butterfly valve, comprising a valve body, a rotating shaft, and a butterfly plate. Both ends of the rotating shaft pass through the valve body and are rotatably connected to the valve body. The butterfly plate is fixed to the rotating shaft and located within the valve body. The valve body also includes a valve seat assembly that is pneumatically driven to move linearly along the axial direction of the medium channel within the valve body. At least a portion of the valve seat assembly near the butterfly plate has a valve seat sealing ring that protrudes from the valve seat assembly. At least a portion of the valve seat sealing ring has a first inclined surface angled to the axis of the medium channel, and the butterfly plate has a second inclined surface aligned with the inclination direction of the first inclined surface. A limiting structure is provided between the valve seat assembly and the valve body to restrict the alternating movement of the valve seat sealing ring between the sealing position and the unsealed position. In the sealing position, the first and second inclined surfaces fit together to seal. A packing cavity is formed between the top of the valve body and the rotating shaft. The packing cavity is provided with a self-tightening sealing packing assembly that is pressed by a packing gland and forms a self-tightening seal with the outer wall of the rotating shaft.

[0006] Preferably, the self-tightening sealing packing assembly includes at least one set of lip-shaped sealing rings and V-shaped tension springs sleeved on the outer wall of the rotating shaft. The lip-shaped sealing rings and the V-shaped tension springs form a sealing unit. The V-shaped tension springs are disposed on the inner side wall of the opening of the lip-shaped sealing rings, and the two outer side walls of the opening of the lip-shaped sealing rings are in contact with the outer wall of the rotating shaft and the side wall of the valve body, respectively.

[0007] Preferably, the outer side wall of the opening of the lip-shaped sealing ring has several protrusions.

[0008] Preferably, along the axial direction of the rotating shaft, a plurality of sealing units are stacked inside the packing cavity, and an intermediate annular space is formed between the lip sealing ring of one of the two adjacent sealing units and the V-shaped tension spring of the other sealing unit; and an inner triangular annular space and an outer triangular annular space are formed between the inner walls of the two adjacent sealing units and the packing cavity, and the intermediate annular space, the inner triangular annular space and the outer triangular annular space of the two adjacent sealing units are triangularly distributed.

[0009] Preferably, the inner wall of the lip-shaped sealing ring is provided with a spring fixing groove that is similar in shape to the V-shaped tension spring, and the V-shaped tension spring is fixed in the spring fixing groove and the inner wall of the V-shaped tension spring is flush with the inner wall of the lip-shaped sealing ring.

[0010] Preferably, the valve seat assembly has a third inclined surface parallel to the first inclined surface at one end where the valve seat sealing ring is located, and at least a portion of the valve seat sealing ring protrudes from the third inclined surface.

[0011] Preferably, the valve body is further provided with an annular groove communicating with the medium channel. The valve seat assembly is annular and slidably installed in the annular groove. The limiting structure includes a limiting groove and an open limiting ring. At least a portion of the limiting groove is provided on the outer wall of the groove opening of the annular groove, and the remaining portion of the limiting groove is provided on the outer wall of the valve seat assembly. The open limiting ring is provided in the limiting groove, and the thickness of the open limiting ring is less than the groove width of the limiting groove.

[0012] Preferably, an external sealing element is provided between the outer wall of the annular groove and the outer wall of the valve seat assembly, an internal sealing element is provided between the inner wall of the annular groove and the inner wall of the valve seat assembly, and an air-filling cavity is formed between the bottom of the annular groove away from the outer wall of the groove opening and the valve seat assembly, and the force-bearing area of ​​the valve seat assembly near the butterfly plate is smaller than the force-bearing area of ​​the valve seat assembly near the air-filling cavity.

[0013] Preferably, the valve body is provided with a plurality of circumferentially distributed air holes that are perpendicularly connected to the annular groove, each air hole being connected to an air filling pipe, and a discharge valve being provided on the air filling pipe.

[0014] Preferably, the valve body is provided with bushings fitted at both ends of the rotating shaft, and defined as a first bushing and a second bushing. The upper end of the first bushing abuts against the lower end of the self-tightening sealing packing assembly, and the lower end of the second bushing abuts against the bearing assembly.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: First, the valve seat assembly moves linearly along the axial direction of the medium passage in the valve body, avoiding friction between the valve seat seal ring and the butterfly plate sealing surface during rotation, thus extending the service life of the valve seat seal ring. When the valve needs to be closed, the butterfly plate first rotates clockwise to its position, and then the valve seat assembly moves linearly along the axial direction of the medium passage in the valve body towards the butterfly plate, so that the valve seat seal ring and the butterfly plate sealing surface are tightly fitted to form a seal; when the valve needs to be opened, the valve seat assembly moves linearly along the axial direction of the medium passage in the valve body away from the butterfly plate, so that the valve seat seal ring disengages from the butterfly plate sealing surface, and then the butterfly plate rotates counterclockwise to open.

[0016] Secondly, the valve seat assembly is pneumatically driven. By converting the pressure of compressed air into mechanical motion, it can respond quickly and precisely control the position of the valve seat assembly, thereby achieving efficient, high-precision, and safe control of the medium.

[0017] Third, the valve seat seal ring and the butterfly plate sealing surface are sealed and matched by an inclined plane. When the valve needs to be closed, the valve seat seal ring is pressed against the butterfly plate sealing surface. As the pressure increases, the sealing surfaces are tightly fitted together. At the same time, the self-locking characteristic of the inclined plane, that is, the pressure angle on the sealing surface is greater than the friction angle, forms a "tighter with pressure" self-sealing effect, effectively preventing relative slippage of the sealing surfaces and media leakage.

[0018] Fourth, a self-tightening sealing packing assembly is provided between the valve body and the rotating shaft. The packing chamber is located between the top of the valve body and the rotating shaft to prevent the medium from leaking through the gap between the rotating shaft and the valve body. When the butterfly valve is opened or closed, the rotating shaft drives the butterfly plate to rotate, and the self-tightening sealing packing assembly in the packing chamber has a pressure-reinforced sealing effect, which can effectively prevent the medium from leaking. Attached Figure Description

[0019] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1A schematic diagram of the structure of a pneumatic piston-type double eccentric high-performance butterfly valve provided in an embodiment of the present invention; Figure 2 Provided for the embodiments of the present invention Figure 1 Enlarged view of point A in the middle; Figure 3 Provided for the embodiments of the present invention Figure 1 Enlarged view of point B in the middle; Figure 4 Provided for the embodiments of the present invention Figure 1 Enlarged view of point C in the middle.

[0020] In the diagram: 1. Valve body; 11. Medium passage; 12. Annular groove; 121. Outer groove wall; 122. Inner groove wall; 13. Outer sealing element; 14. Inner sealing element; 15. Inflation chamber; 151. Inflation hole; 152. Discharge valve; 2. Rotary shaft; 21. Bushing; 3. Butterfly plate; 4. Valve seat assembly; 41. Valve seat sealing ring; 411. First inclined surface; 42. Third inclined surface; 5. Limiting structure; 51. Limiting groove; 52. Opening limiting ring; 61. Self-tightening sealing packing assembly; 611. Sealing unit; 612. V-shaped tension spring; 613. Lip seal ring; 6131. ​​Protrusion; 6132. Spring fixing groove; 614. Intermediate annular space; 615. Inner triangular annular space; 616. Outer triangular annular space; 62. Packing gland; 7. Bearing assembly; 71. Split ring; 72. Thrust ball bearing; 73. Adjusting screw; 74. Support end cover; 75. Bottom seal cover; 8. Air source terminal; 81. First solenoid valve; 9. Actuator; 91. Limit switch; 92. Second solenoid valve; 10. Wedge pin. Detailed Implementation

[0021] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0022] See Figure 1 This embodiment provides a pneumatic piston type double eccentric high-performance butterfly valve, including a valve body 1, a rotating shaft 2 and a butterfly plate 3. The two ends of the rotating shaft 2 pass through the valve body 1 and the rotating shaft 2 and the valve body 1 are rotatably connected. The butterfly plate 3 is fixed to the rotating shaft 2 and is located inside the valve body 1.

[0023] Preferably, the butterfly plate 3 and the rotating shaft 2 are connected by a wedge pin 10. In conventional valves, a cylindrical pin is used to connect the butterfly plate 3 and the rotating shaft 2. There is a gap between the cylindrical pin and the rotating shaft 2 and the butterfly plate 3. In this embodiment, the wedge pin 10 is used to connect the butterfly plate 3 and the rotating shaft 2, which can eliminate the fit gap and enhance the shear resistance.

[0024] See Figure 1 and Figure 2 The valve body 1 also includes an annular groove 12 communicating with the medium channel 11, and a valve seat assembly 4 that is pneumatically driven to move linearly along the axial direction of the medium channel 11 in the valve body 1. The valve seat assembly 4 is annular and slidably installed within the annular groove 12. The medium channel 11 is the path for the flow of the medium (fluid) within the valve body 1, used to accommodate and guide the valve seat assembly 4 to perform linear reciprocating motion, ensuring the smooth movement of the valve seat assembly 4. The valve seat assembly 4 is pneumatically driven, converting the pressure of compressed air into mechanical motion, enabling rapid response (such as signals from industrial automation systems) and precise control of the position of the valve seat assembly 4, thereby achieving efficient, high-precision, and safe control of the medium.

[0025] See Figure 1 and Figure 2 An outer sealing element 13 is provided between the outer wall 121 of the annular groove 12 and the outer wall of the valve seat assembly 4. An inner sealing element 14 is provided between the inner wall 122 of the annular groove 12 and the inner wall of the valve seat assembly 4. An air-filling chamber 15 is formed between the bottom of the annular groove 12 away from the groove opening and the valve seat assembly 4. The annular groove 12 and the valve seat assembly 4 are relatively sealed by the outer sealing element 13 and the inner sealing element 14, thereby forming an air-filling chamber 15 that contains compressed air. The air-filling chamber 15 is used to provide pressure control for driving the valve seat assembly 4 to perform linear motion, ensuring the efficient operation of the system.

[0026] See Figure 1 and Figure 2 The valve body 1 has several circumferentially distributed inflation holes 151 that are perpendicularly connected to the inflation chamber 15 of the annular groove 12. Each inflation hole 151 is connected to an inflation pipeline, which is connected in parallel to the gas source terminal 8 (such as an energy storage tank). A discharge valve 152 (or quick discharge valve) is provided on the inflation pipeline. The gas source terminal 8 is used to store the gas generated by the air compressor, and the storage pressure of the gas source terminal 8 is controlled by a pressure switch. When the pressure of the gas source terminal 8 rises to 0.8 MPa, the air compressor stops supplying gas; when the pressure of the gas source terminal 8 drops to 0.7 MPa, the air compressor supplies gas; when the pressure of the gas source terminal 8 drops to 0.5 MPa, a fault alarm is triggered. For example, a first solenoid valve 81 (such as a two-position three-way solenoid valve) is normally open between the gas source terminal 8 and the discharge valve 152 to control the intake or exhaust of the inflation chamber 15.

[0027] See Figure 1 and Figure 2 A valve seat sealing ring 41, at least partially protruding from the valve seat assembly 4, is provided at one end of the valve seat assembly 4 near the butterfly plate 3. At least a portion of the valve seat sealing ring 41 has a first inclined surface 411 angled to the axis of the medium passage 11, and the butterfly plate 3 has a second inclined surface with the same inclination direction as the first inclined surface 411. In the sealed position, the first inclined surface 411 and the second inclined surface fit together to seal. When the butterfly plate 3 rotates to the sealed position, the linear movement of the first inclined surface 411 (valve seat sealing ring 41) and its engagement with the second inclined surface (butterfly plate 3) create an effective barrier in the sealed position, and the engagement of the two inclined surfaces effectively prevents medium leakage.

[0028] See Figure 1 and Figure 2 The valve seat assembly 4 has a third inclined surface 42 at one end where the valve seat sealing ring 41 is located, which is parallel to the first inclined surface 411. At least a portion of the valve seat sealing ring 41 protrudes from the third inclined surface 42. The valve seat sealing ring 41 is preferably made of an elastic material, which allows it to deform under stress. When the valve is closed, the valve seat sealing ring 41 protruding from the third inclined surface 42 forms a larger contact area or fits more tightly with the butterfly plate 3, which can maintain a good sealing state under different operating conditions (such as pressure changes).

[0029] See Figure 1 and Figure 2 The force-bearing area S2 of the valve seat assembly 4 near the butterfly plate 3 is smaller than the force-bearing area S1 of the valve seat assembly 4 near the inflation chamber 15, and the gas pressure from the gas source terminal 8 is greater than the gas pressure from the medium channel 11. The gas pressure from the gas source terminal 8 is, for example, 0.8 MPa, and the gas pressure from the medium channel 11 is, for example, 0.5 MPa.

[0030] See Figure 1 and Figure 2 A limiting structure 5 is provided between the valve seat assembly 4 and the valve body 1 to restrict the alternating movement of the valve seat sealing ring 41 in the sealing position and the unsealed position. The limiting structure 5 includes a limiting groove 51 and an open limiting ring 52. The open limiting ring 52 is disposed in the limiting groove 51. At least a portion of the limiting groove 51 is disposed on the outer groove wall 121 of the annular slide groove 12, and the remaining portion of the limiting groove 51 is disposed on the outer wall of the valve seat assembly 4. Since the open limiting ring 52 is an annular element with an opening, the open limiting ring 52 has an outward expansion elasticity. When the open limiting ring 52 is disposed in the limiting groove 51, its outer side wall automatically abuts against at least a portion of the limiting groove 51 disposed on the outer groove wall 121 of the annular slide groove 12, and its inner side wall is located in the remaining portion of the limiting groove 51 disposed on the valve seat assembly 4.

[0031] See Figure 1 and Figure 2The thickness of the opening limiting ring 52 is less than the groove width of the limiting groove 51, so that there is relative movement space between the valve seat assembly 4 and the valve body 1, while it will not disengage from the limiting groove 51, thereby effectively limiting the movement stroke of the valve seat sealing ring 41.

[0032] See Figure 1 and Figure 3 A packing cavity is formed between the top of the valve body 1 and the rotating shaft 2. The packing cavity is equipped with a self-tightening sealing packing assembly 61, which is pressed by the packing gland 62 and forms a self-tightening seal with the outer wall of the rotating shaft 2. When the butterfly valve is opened or closed, the rotating shaft 2 drives the butterfly plate 3 to rotate. The self-tightening sealing packing assembly 61 in the packing cavity has a pressure-reinforced sealing effect, which can effectively prevent the medium from leaking from the gap between the rotating shaft 2 and the valve body 1.

[0033] See Figure 1 and Figure 3 The self-tightening sealing packing assembly 61 includes at least one set of lip-shaped sealing rings 613 and V-shaped tension springs 612 sleeved on the outer wall of the rotating shaft 2. The V-shaped tension springs 612 are located on the inner side wall of the opening of the lip-shaped sealing rings 613, and the two outer side walls of the opening of the lip-shaped sealing rings 613 contact the outer wall of the rotating shaft 2 and the side wall of the valve body 1, respectively. The V-shaped tension springs 612 provide a continuous initial radial tension force for the lip-shaped sealing rings 613. When the packing gland 62 applies a pre-tightening force, the lip-shaped sealing rings 613 further conform to the rotating shaft 2 and the valve body 1 under the action of the V-shaped springs, improving the reliability and adaptability of the seal. The self-tightening sealing packing assembly 61 achieves self-tightening sealing of the rotating shaft 2 with a relatively small pre-tightening force of the packing gland 62, reducing the coefficient of friction, reducing the valve opening and closing torque, preventing media leakage, and adapting to certain axial and radial displacements.

[0034] See Figure 1 and Figure 3 The outer wall of the lip seal ring 613 has several protrusions 6131, which increase the contact points between the lip seal ring 613 and the rotating shaft 2 and valve body 1, disperse pressure, and make the seal more uniform and reliable. In the presence of vibration, impact, or particulate matter in the medium, the protrusions 6131 can better maintain the sealing state and prevent leakage.

[0035] See Figure 1 and Figure 3A lip-shaped sealing ring 613 and a V-shaped tension spring 612 form a sealing unit 611. In the axial direction of the rotating shaft 2, several sealing units 611 are stacked inside the packing cavity. An intermediate annular space 614 is formed between the lip-shaped sealing ring 613 of one sealing unit 611 and the V-shaped tension spring 612 of the other sealing unit 611. An inner triangular annular space 615 and an outer triangular annular space 616 are formed between the inner walls of the packing cavity and the two adjacent sealing units 611. The intermediate annular space 614, the inner triangular annular space 615 and the outer triangular annular space 616 of the two adjacent sealing units 611 are triangularly distributed. The intermediate annular space 614, the inner triangular annular space 615 and the outer triangular annular space 616 are all closed annular spaces to restrict the axial displacement of the sealing unit 611 along the rotating shaft 2. The interaction of multiple closed annular spaces effectively restricts the displacement of the sealing unit 611 along the axial direction of the rotating shaft 2, thereby enhancing the overall stability and sealing effect and preventing internal media leakage or external impurities from entering.

[0036] See Figure 1 and Figure 3 The inner wall of the lip-shaped sealing ring 613 is provided with a spring fixing groove 6132 that is shaped like the V-shaped tension spring 612. The V-shaped tension spring 612 is fixed in the spring fixing groove 6132, and the inner wall of the V-shaped tension spring 612 is flush with the inner wall of the lip-shaped sealing ring 613. The spring fixing groove 6132 is used to accommodate and wrap the V-shaped tension spring 612, so as to avoid excessive wear of the V-shaped tension spring 612 during the self-tightening sealing process, which would affect the sealing effect. The flushness between the inner wall of the V-shaped tension spring 612 and the inner wall of the lip-shaped sealing ring 613 allows the outer wall of one lip-shaped sealing ring 613 to fit against part of the inner wall of the other lip-shaped sealing ring 613 and the inner wall of the other V-shaped tension spring 612 when two adjacent sealing units 611 are stacked, so as to form a seal and maintain a certain compressive strength.

[0037] See Figure 1 and Figure 4 The valve body 1 is provided with bushings 21 fitted at both ends of the rotating shaft 2, and are defined as the first bushing and the second bushing. The upper end of the first bushing abuts against the lower end of the self-tightening sealing packing assembly 61, and the lower end of the second bushing abuts against the bearing assembly 7.

[0038] The first and second bushings are preferably oil-free, self-lubricating bushings.

[0039] See Figure 1 and Figure 4 The bearing assembly 7 includes a split ring 71, a thrust ball bearing 72, and an adjusting screw 73. One end of the rotating shaft 2, which has a second bushing 21, passes through the split ring 71 and extends into the support end cover 74 at the bottom of the valve body 1, and is connected to the adjusting screw 73 through the thrust ball bearing 72.

[0040] See Figure 1 and Figure 4 At least a portion of the split ring 71 is fixed inside the valve body 1 by the support end cap 74, and the remaining portion of the split ring 71 is engaged within the rotating shaft 2 to prevent the rotating shaft 2 and the butterfly plate 3 from moving up and down. Sealing rings are provided between the support end cap 74, the valve body 1, and the thrust ball bearing 72 for sealing. The support end cap 74 is fixed to the valve body 1 by the bottom seal cap 75. The adjusting screw 73 is used to adjust the center position of the butterfly plate 3 when it droops. The thrust ball bearing 72 reduces the relative friction between the rotating shaft 2 and the adjusting screw 73.

[0041] See Figure 1 The rotating shaft 2 has a first bushing 21 at one end connected to the actuator 9 (such as a double self-acting pneumatic actuator 9). The actuator 9 controls the butterfly plate 3 to rotate through the second solenoid valve 92 (such as a two-position five-way solenoid valve) to open or close the valve.

[0042] The specific valve switching process of the pneumatic piston type double eccentric high-performance butterfly valve provided in this embodiment is as follows: The valve is initially fully closed.

[0043] Valve opening control program: Valve opening command - The coil of the first solenoid valve 81 is energized, the air chamber 15 is in the exhaust state, and at the same time, after two seconds of timing by the time relay, the coil of the second solenoid valve 92 is energized, and the actuator 9 drives the butterfly plate 3 to rotate and open the valve.

[0044] Valve closing control procedure: Valve closing command - the coil of the second solenoid valve 92 is de-energized, the actuator 9 drives the butterfly plate 3 to rotate and close the valve. After closing, the first solenoid valve 81 is de-energized through the limit switch 91, and compressed air enters the inflation chamber 15.

[0045] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program goods. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program goods embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0046] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program goods according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0047] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0048] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A pneumatic piston-type double eccentric high-performance butterfly valve, comprising a valve body (1), a rotating shaft (2), and a butterfly plate (3), wherein both ends of the rotating shaft (2) are inserted into the valve body (1) and the rotating shaft (2) and the valve body (1) are rotatably connected, and the butterfly plate (3) is fixed to the rotating shaft (2) and located within the valve body (1), characterized in that, The valve body (1) is further provided with a valve seat assembly (4) that moves linearly along the axial direction of the medium channel (11) of the valve body (1) by pneumatic drive. A valve seat sealing ring (41) is provided at least partially protruding from the valve seat assembly (4) at one end of the valve seat assembly (4) near the butterfly plate (3). At least a portion of the valve seat sealing ring (41) has a first inclined surface (411) that is angled to the axis of the medium channel (11), and the butterfly plate (3) has a second inclined surface that is in the same direction as the first inclined surface (411). A limiting structure (5) is provided between the valve seat assembly (4) and the valve body (1) to limit the alternating movement of the valve seat sealing ring (41) in the sealing position and the unsealed position. In the sealing position, the first inclined surface (411) and the second inclined surface fit together to seal. A packing cavity is formed between the top of the valve body (1) and the rotating shaft (2), and a self-tightening sealing packing assembly (61) is provided in the packing cavity, which is pressed by the packing gland (62) and forms a self-tightening seal with the outer wall of the rotating shaft (2).

2. The pneumatic piston-type double eccentric high-performance butterfly valve according to claim 1, characterized in that, The self-tightening sealing packing assembly (61) includes at least one set of lip seal rings (613) and V-shaped tension springs (612) sleeved on the outer wall of the rotating shaft (2). The lip seal rings (613) and the V-shaped tension springs (612) form a sealing unit (611). The V-shaped tension springs (612) are located on the inner side wall of the opening of the lip seal rings (613), and the two outer side walls of the opening of the lip seal rings (613) are in contact with the outer wall of the rotating shaft (2) and the side wall of the valve body (1), respectively.

3. The pneumatic piston-type double eccentric high-performance butterfly valve according to claim 2, characterized in that, The outer side wall of the opening of the lip-shaped sealing ring (613) has several protrusions (6131).

4. A pneumatic piston-type double eccentric high-performance butterfly valve according to claim 2 or 3, characterized in that, Along the axial direction of the rotating shaft (2), a plurality of sealing units (611) are stacked inside the packing cavity, and an intermediate annular space (614) is formed between the lip sealing ring (613) of one of the two adjacent sealing units (611) and the V-shaped tension spring (612) of the other sealing unit (611); and an inner triangular annular space (615) and an outer triangular annular space (616) are formed between the two adjacent sealing units (611) and the inner wall of the packing cavity, and the intermediate annular space (614), the inner triangular annular space (615) and the outer triangular annular space (616) of the two adjacent sealing units (611) are triangularly distributed.

5. A pneumatic piston-type double eccentric high-performance butterfly valve according to claim 2 or 3, characterized in that, The inner wall of the lip-shaped sealing ring (613) is provided with a spring fixing groove (6132) that is similar in shape to the V-shaped tension spring (612), and the V-shaped tension spring (612) is fixed in the spring fixing groove (6132) and the inner wall of the V-shaped tension spring (612) is flush with the inner wall of the lip-shaped sealing ring (613).

6. A pneumatic piston-type double eccentric high-performance butterfly valve according to claim 1, characterized in that, The valve seat assembly (4) has a third inclined surface (42) at one end where the valve seat seal ring (41) is provided, which is parallel to the first inclined surface (411), and at least a portion of the valve seat seal ring (41) protrudes from the third inclined surface (42).

7. A pneumatic piston-type double eccentric high-performance butterfly valve according to claim 1, characterized in that, The valve body (1) is also provided with an annular groove (12) communicating with the medium channel (11). The valve seat assembly (4) is annular and is slidably installed in the annular groove (12). The limiting structure (5) includes a limiting groove (51) and an open limiting ring (52). At least a portion of the limiting groove (51) is provided on the outer groove wall (121) of the groove opening of the annular groove (12). The remaining portion of the limiting groove (51) is provided on the outer wall of the valve seat assembly (4). The open limiting ring (52) is provided in the limiting groove (51) and the thickness of the open limiting ring (52) is less than the groove width of the limiting groove (51).

8. A pneumatic piston-type double eccentric high-performance butterfly valve according to claim 7, characterized in that, An outer sealing element (13) is provided between the outer groove wall (121) of the annular slide (12) and the outer wall of the valve seat assembly (4). An inner sealing element (14) is provided between the inner groove wall (122) of the annular slide (12) and the inner wall of the valve seat assembly (4). An air-filling cavity (15) is formed between the bottom of the annular slide (12) away from the groove opening and the valve seat assembly (4). The force-bearing area of ​​the valve seat assembly (4) near the butterfly plate (3) is smaller than the force-bearing area of ​​the valve seat assembly (4) near the air-filling cavity (15).

9. A pneumatic piston-type double eccentric high-performance butterfly valve according to claim 7 or 8, characterized in that, The valve body (1) is provided with a plurality of circumferentially distributed air holes (151) that are perpendicularly connected to the annular slide groove (12). Each air hole (151) is connected to an air filling pipeline, and a discharge valve (152) is provided on the air filling pipeline.

10. A pneumatic piston-type double eccentric high-performance butterfly valve according to claim 1, characterized in that, The valve body (1) is provided with bushings (21) fitted at both ends of the rotating shaft (2), and are defined as the first bushing and the second bushing. The upper end of the first bushing abuts against the lower end of the self-tightening sealing packing assembly (61), and the lower end of the second bushing abuts against the bearing assembly (7).

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