Double-seal double-discharge three-eccentric metal hard seal butterfly valve

Abstract

A double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve features a double-seal ring structure between the butterfly plate and the valve seat. The annular groove structure formed between the double-seal ring structure and the valve seat ensures that when a high-pressure medium passes through the first seal ring, if some leaking medium crosses the first seal ring and enters the annular groove, the medium pressure in the annular groove will be lower than the pressure of the medium inside the valve cavity. When the pressure of the medium in the annular groove is too low, the low-pressure medium cannot cross the second seal ring and enter the rightmost valve cavity. Furthermore, the discharge purging device can be connected to either a purging device for steam purging and cleaning of the seal rings or a grease injection device to inject grease into the annular groove using a grease gun for emergency sealing.

Description

Technical Field

[0001] This invention relates to the field of butterfly valve technology, specifically to a double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve. Background Technology

[0002] During the application of industrial butterfly valves, problems such as leakage, corrosion, and blockage are common. Leakage is generally caused by the presence of foreign objects or wear leading to sealing surface failure. Corrosion occurs because the transmitted medium contains corrosive elements, valve components lack effective anti-corrosion measures, or wear damages the anti-corrosion layer. Blockage in butterfly valves is usually due to impurities or viscous media, causing impurities to accumulate, adhere, or block the sealing ring and valve seat, resulting in incomplete closure of the butterfly plate, leakage, or inability to open properly. In actual operating conditions, welding slag, rust, or particulate impurities in the medium easily accumulate on the sealing surface. Viscous media such as tar can also easily accumulate at the valve seat or valve shaft and bushing, making it difficult to rotate and open the valve plate or causing shutdown. In such cases, shutdown and maintenance are generally required, either by disassembling the valve from the pipeline for offline repair or by introducing gas or steam into the pipeline for flushing. If the blockage is severe, steam flushing may not be effective.

[0003] Currently, in harsh operating conditions, when the pipeline medium is high-viscosity dust, particles, or iron filings, the gap between the valve stem and bushing of the triple eccentric butterfly valve causes the high-viscosity medium to adhere to the valve stem and bushing within the valve body during operation. This can lead to the valve stem seizing against the valve body during rotation, thus reducing the valve's service life. Triple eccentric hard-seal butterfly valves have the following disadvantages: Existing triple eccentric butterfly valves either lack a purging structure or have a one-way purging structure. Since the sealing ring is fixed to the butterfly plate, when the butterfly plate is normally open, the medium directly impacts its sealing surface, causing wear and tear, directly affecting sealing performance. When the butterfly plate is closed, the valve body seat can easily lead to medium accumulation and jamming at the sealing surface, resulting in a tight seal and further reducing the valve's service life. Summary of the Invention

[0004] In view of this, the present invention provides a double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve includes a valve body and a valve shaft. A valve cavity is formed within the valve body, and a valve seat and a butterfly plate are disposed within the valve cavity. One end of the valve shaft extends into the valve cavity and connects to the butterfly plate. The butterfly plate has a butterfly plate sealing surface, and the valve seat has a valve seat sealing surface. A double-seal ring structure is disposed between the butterfly plate sealing surface and the valve seat sealing surface. The two ends of the double-seal ring structure correspondingly abut against the butterfly plate and the valve seat. A double-discharge purging device is disposed on the valve body, and a purging channel is disposed on the valve body. One end of the double-discharge purging device extends into the purging channel and connects to the valve body. A connecting channel is formed on the valve seat, and the end of the purging channel away from the double-discharge purging device communicates with the connecting channel of the valve seat. The double-discharge purging device purges and seals the valve seat, butterfly plate, and double-seal ring structure within the valve cavity through the purging channel and the connecting channel.

[0007] Preferably, the double sealing ring structure includes a first sealing ring and a second sealing ring. The butterfly plate sealing surface is stepped, having a first stepped surface and a second stepped surface. The first sealing ring is disposed on the first stepped surface, and the second sealing ring is disposed on the second stepped surface. The first and second sealing rings are respectively provided with a first sealing end and a second sealing end. Both the first and second sealing ends abut against the valve seat sealing surface of the valve seat. A wear-resistant sealing structure is formed between the first sealing end, the second sealing end, and the valve seat. An annular groove is formed between the valve seat sealing surface, the first sealing ring, and the second sealing ring, and the annular groove communicates with the connecting channel.

[0008] Preferably, the second sealing ring is disposed on the side of the first sealing ring away from the first stepped surface, the second sealing ring is fixed on the second stepped surface by screws, and one end of the second sealing ring is pressed and fixed to the first sealing ring.

[0009] Preferably, the dual-emission purging device includes a first purging element and a second purging element, and the purging channel is provided with a first purging channel and a second purging channel corresponding to the first purging element and the second purging element. The first purging element and the second purging element extend into the corresponding first purging channel and the second purging channel. The first purging channel is connected to the connecting channel of the valve seat, and the second purging channel is connected to the valve cavity.

[0010] Preferably, a curved groove is formed between the bottom of the second purge channel and the valve seat, one end of the curved groove is connected to the second purge channel, and the other end of the curved groove is connected to the valve cavity.

[0011] Preferably, the curved groove is C-shaped, with the groove opening at the end near the valve cavity facing the valve seat and the second sealing ring.

[0012] Preferably, the second sealing ring is a pressure ring structure, wherein the second sealing ring is a sealing pressure ring disposed on one side of the first sealing ring and pressing the first sealing ring, and the second sealing end is a protruding end integrally formed on the sealing pressure ring.

[0013] Preferably, the valve seat and the valve body are detachable. A valve seat pressure ring is provided on one side of the valve seat, and a three-part retaining ring is provided on the side of the valve seat pressure ring away from the valve seat. A retaining ring groove is provided on the valve body, and the three-part retaining ring is disposed in the retaining ring groove. A set screw is provided on the three-part retaining ring, and the set screw passes through the three-part retaining ring to press and fix the valve seat pressure ring toward the valve seat.

[0014] The beneficial effects of this invention are as follows: By setting a double sealing ring structure between the butterfly plate and the valve seat, and the annular groove structure formed between the double sealing ring structure and the valve seat, when the medium with high pressure passes through the first sealing ring, if some leaking medium crosses the first sealing ring and enters the annular groove, the medium pressure in the annular groove will be less than the pressure of the medium in the valve cavity. When the pressure of the medium in the annular groove is too low, the low-pressure medium cannot cross the second sealing ring and enter the rightmost valve cavity. Furthermore, the exhaust purging device can be connected to a purging device to perform steam purging and cleaning of the sealing ring, or it can be connected to a grease injection device to inject grease into the annular groove with a grease injection gun to achieve emergency sealing. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Appendix Figure 1 This is a schematic diagram of the structure of the present invention;

[0017] Appendix Figure 2 This is a cross-sectional view of the present invention;

[0018] Appendix Figure 3 This is a longitudinal sectional view of the present invention;

[0019] Appendix Figure 4 For the appendix Figure 3 Enlarged view of point A in the image.

[0020] Figure label:

[0021] 1. Valve body, 2. Valve shaft, 3. Valve cavity, 4. Valve seat, 5. Butterfly plate, 6. Butterfly plate sealing surface, 7. Valve seat sealing surface, 8. Double-discharge purging device, 9. Purging channel, 10. Connecting channel, 11. First sealing ring, 12. Second sealing ring, 13. First stepped surface, 14. Second stepped surface, 15. First sealing end, 16. Second sealing end, 17. Annular groove, 18. First purging discharge component, 19. Second purging discharge component, 20. First purging channel, 21. Second purging channel, 22. Curved groove, 23. First sealing groove, 24. Second sealing groove, 25. First sealing gasket, 26. Second sealing gasket, 27. Valve seat pressure ring, 28. Three-part retaining ring, 29. Retaining ring groove, 30. Set screw. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] The present invention will now be further described with reference to the accompanying drawings.

[0024] This invention provides the following technical solution:

[0025] As attached Figures 1-4As shown, this invention discloses a double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve, including a valve body 1 and a valve shaft 2. A valve cavity 3 is formed within the valve body 1, and a valve seat 4 and a butterfly plate 5 are disposed within the valve cavity 3. One end of the valve shaft 2 extends into the valve cavity 3 and connects to the butterfly plate 5. The butterfly plate 5 has a butterfly plate sealing surface 6, and the valve seat 4 has a valve seat sealing surface 7. A double sealing ring structure is disposed between the butterfly plate sealing surface 6 and the valve seat sealing surface 7. The two ends of the double sealing ring structure abut against the butterfly plate 5 and the valve seat 4 respectively. A double-discharge purging device 8 is disposed on the valve body 1, and a purging channel 9 is disposed on the valve body 1. One end of the double-discharge purging device 8 extends into the purging channel 9 and connects to the valve body 1. A connecting channel 10 is opened on the valve seat 4, and the end of the purging channel 9 away from the double-discharge purging device 8 communicates with the connecting channel 10 of the valve seat 4. The double-discharge purging device 8 performs purging and sealing of the valve seat 4, butterfly plate 5, and double sealing ring structure within the valve cavity 3 through the purging channel 9 and the connecting channel 10. Specifically, this design incorporates a double sealing ring structure between the butterfly plate 5 and the valve seat 4. The annular groove 17 formed between the double sealing ring structure and the valve seat 4 ensures that when the high-pressure medium passes through the first sealing ring 11, if some leaking medium crosses the first sealing ring 11 and enters the annular groove 17, the medium pressure in the annular groove 17 will be less than the pressure of the medium in the valve cavity 3. When the pressure of the medium in the annular groove 17 is too low, the low-pressure medium cannot cross the second sealing ring 12 and enter the rightmost valve cavity 3. Furthermore, the exhaust purging device can be connected to either a purging device to perform steam purging and cleaning of the sealing rings or a grease injection device to inject grease into the annular groove using a grease injection gun to achieve emergency sealing.

[0026] The dual-seal ring structure includes a first seal ring 11 and a second seal ring 12. The butterfly plate sealing surface 6 is stepped, having a first stepped surface 13 and a second stepped surface 14. The first seal ring 11 is disposed on the first stepped surface 13, and the second seal ring 12 is disposed on the second stepped surface 14. The first seal ring 11 and the second seal ring 12 are respectively provided with a first sealing end 15 and a second sealing end 16. Both the first sealing end 15 and the second sealing end 16 abut against the valve seat sealing surface 7 of the valve seat 4, thereby forming a wear-resistant sealing structure and increasing the resistance of the medium in the flow. The purpose of reducing leakage is to mitigate the resistance at this location. After the medium passes through the first sealing ring 11, even if there is some leakage, the pressure value is greatly reduced after passing through the intermediate groove, making it difficult for the medium to leak out through the second sealing ring 12. An annular groove 17 is formed between the first sealing end 15, the second sealing end 16, and the valve seat 4. Both the first sealing end 15 and the second sealing end 16 have inclined portions with the same angle and direction. The inclined portions of the first sealing end 15 and the second sealing end 16 are in contact with the valve seat sealing surface 7. The connecting channel 10 on the valve seat 4 communicates with the annular groove 17. Specifically, in this embodiment, since the valve seat sealing surface 7 is inclined, the butterfly plate sealing surface 6 is set as a stepped structure, so that the first sealing ring 11 and the second sealing ring 12 are installed on the first stepped surface 13 and the second stepped surface 14 respectively, so that the first sealing ends 15 and the second sealing ends 16 of the first sealing ring 11 and the second sealing ring 12 are on the same inclined line, so that when the butterfly valve is closed, they are in contact with the valve seat sealing surface 7 to form an annular groove 17 with good sealing performance.

[0027] The second sealing ring 12 is disposed on the side of the first sealing ring 11 away from the first stepped surface 13. The second sealing ring 12 is fixed to the second stepped surface 14 by screws, and one end of the second sealing ring 12 presses and fixes the first sealing ring 11. Specifically, the second sealing ring 12 is a pressure ring structure. The second sealing ring 12 is a sealing pressure ring disposed on one side of the first sealing ring 11 and pressing the first sealing ring 11. The second sealing end 16 is an integrally formed protrusion on the sealing pressure ring, which is a structure formed by the second sealing ring 12 protruding towards the valve seat 4. Specifically, by designing the sealing pressure ring as the structure of the second sealing ring, the first sealing ring 11 can be pressed while the second sealing end 16 is pressurized on the sealing pressure ring, which enhances the sealing performance without the need for an additional sealing ring, reducing installation space and cost.

[0028] In this embodiment, the first sealing ring 11 and the second sealing ring 12 are each provided with a corresponding first sealing groove 23 and a second sealing groove 24. The first sealing groove 23 and the second sealing groove 24 are provided with corresponding first sealing gaskets 25 and second sealing gaskets 26. The two ends of the first sealing gasket 25 abut against the groove wall of the first sealing groove 23 of the first sealing ring 11 and the outer wall of the second sealing ring 12. The two ends of the second sealing gasket 26 abut against the groove wall of the second sealing groove 24 and the second stepped surface 14 of the butterfly plate 5. This arrangement can form a corresponding static sealing structure between the first sealing gasket 25 and the second sealing gasket 26, forming a double seal with the corresponding sealing ring, thereby improving the overall sealing performance.

[0029] The dual-emission purging device 8 includes a first purging and emission component 18 and a second purging and emission component 19. The purging channel 9 is provided with a first purging channel 20 and a second purging channel 21 corresponding to the first purging and emission component 18 and the second purging and emission component 19. The first purging and emission component 18 and the second purging and emission component 19 extend into the corresponding first purging channel 20 and the second purging channel 21. The first purging channel 20 is connected to the connecting channel 10 of the valve seat 4, and the second purging channel 21 is connected to the valve cavity 3. Specifically, in this design, depending on the medium in the valve cavity 3, the first purge discharge component 18 and the second purge discharge component 19 can be grease injection valves or purging devices. When the medium in the valve cavity 3 is particulate such as tar, asphalt, dust, silica powder, coal slag, and iron filings, the first purge discharge component 18 and the second purge discharge component 19 can be filled with high-temperature steam to powerfully purge the valve body 1 seat and the two sealing rings, keeping the sealing pair clean at all times, thereby ensuring the sealing effect. When the sealing ring fails and the medium is flammable, explosive, toxic, or corrosive gas, the first purge discharge component 18 and the second purge discharge component 19 can also be grease injection valves. The grease injection valves inject sealing grease into the annular groove 17 and the curved groove 22, forming an emergency sealing ring between the valve seat 4 and the double sealing ring structure, thereby ensuring the sealing effect of the double sealing ring structure.

[0030] A curved groove 22 is formed between the bottom of the second purge channel 21 and the valve seat 4. One end of the curved groove 22 is connected to the second purge channel 21, and the other end is connected to the valve cavity 3. The curved groove 22 is C-shaped, with the opening of the groove near the valve cavity 3 facing the valve seat 4 and the second sealing ring 12. Specifically, in order to ensure that the second purge discharge component 19 can purge the valve seat 4 and the first sealing ring 11, the curved groove 22 set between the bottom of the second purge channel 21 and the valve seat 4 in this embodiment can prevent high-temperature steam from directly entering the valve cavity 3 after passing through the second purge channel 21, thus preventing the outer side of the valve seat 4 and the side of the second sealing ring 12 near the valve cavity 3 from being purged. The curved groove 22 can change the path of the high-temperature steam, so that the high-temperature steam changes the blowing direction in the curved groove 22 and then purges the valve seat 4 and the second sealing ring 12.

[0031] Furthermore, the valve seat 4 and the valve body 1 are detachable. A valve seat pressure ring 27 is provided on one side of the valve seat 4, and a three-part retaining ring 28 is provided on the side of the valve seat pressure ring 27 away from the valve seat 4. A retaining ring groove 29 is provided on the valve body 1, and the three-part retaining ring 28 is disposed in the retaining ring groove 29. A set screw 30 is provided on the three-part retaining ring 28. The set screw 30 passes through the three-part retaining ring 28 to press and fix the valve seat pressure ring 27 toward the valve seat 4. In this embodiment, the valve seat 4 and the valve body 1 are sealed by a sealing gasket.

[0032] In this design, the valve seat sealing surface 7 and the corresponding first sealing end 15 of the first sealing ring 11 and the second sealing end 16 of the second sealing ring 12 are both obliquely placed elliptical sealing surfaces. Therefore, in Figure 3 As shown in the figure, the sealing structures at both ends are not symmetrical. According to the cam principle, the first sealing ring 11 and the second sealing ring 12, which are obliquely placed ellipses, do not interfere with the valve seat during the rotation and opening process around the valve shaft 2. When the first sealing ring 11 and the second sealing ring 12 reach the closed position, they completely fit with the valve seat 4 to form a seal; when they open, the first sealing ring 11 and the second sealing ring 12 disengage from the valve seat.

[0033] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve, comprising a valve body and a valve shaft, characterized in that: A valve cavity is formed within the valve body, and a valve seat and a butterfly plate are disposed within the valve cavity. One end of the valve shaft extends into the valve cavity and connects to the butterfly plate. The butterfly plate has a butterfly plate sealing surface, and the valve seat has a valve seat sealing surface. A double sealing ring structure is disposed between the butterfly plate sealing surface and the valve seat sealing surface. The two ends of the double sealing ring structure correspondingly abut against the butterfly plate and the valve seat. A double-discharge purging device is disposed on the valve body, and a purging channel is disposed on the valve body. One end of the double-discharge purging device extends into the purging channel and connects to the valve body. A connecting channel is provided on the valve seat, and the end of the purging channel away from the double-discharge purging device is connected to the valve seat. The dual-emission purging device purges and seals the valve seat, butterfly plate, and double sealing ring structure within the valve cavity through a purging channel and a connecting channel. The dual-emission purging device includes a first purging component and a second purging component. The purging channel is provided corresponding to the first purging component and the second purging component. A curved groove is formed between the bottom of the second purging channel and the valve seat. One end of the curved groove is connected to the second purging channel, and the other end of the curved groove is connected to the valve cavity. The curved groove is C-shaped, and the groove opening near the valve cavity faces the valve seat and the second sealing ring.

2. The double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve according to claim 1, characterized in that: The double sealing ring structure includes a first sealing ring and a second sealing ring. The butterfly plate sealing surface is stepped, having a first stepped surface and a second stepped surface. The first sealing ring is disposed on the first stepped surface, and the second sealing ring is disposed on the second stepped surface. The first and second sealing rings are respectively provided with a first sealing end and a second sealing end. Both the first and second sealing ends abut against the valve seat sealing surface of the valve seat. An annular groove wear-resistant sealing structure is formed between the first sealing end, the second sealing end, and the valve seat. An annular groove is formed between the valve seat sealing surface, the first sealing ring, and the second sealing ring, and the annular groove communicates with the connecting channel.

3. The double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve according to claim 2, characterized in that: The second sealing ring is disposed on the side of the first sealing ring away from the first stepped surface. The second sealing ring is fixed on the second stepped surface by screws, and one end of the second sealing ring presses and fixes the first sealing ring.

4. The double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve according to claim 1, characterized in that: The first purge member and the second purge member extend into the corresponding first purge channel and the second purge channel. The first purge channel is connected to the connection channel of the valve seat, and the second purge channel is connected to the valve cavity.

5. The double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve according to claim 2, characterized in that: The second sealing ring is a pressure ring structure. The second sealing ring is a sealing pressure ring that is set on one side of the first sealing ring and presses against the first sealing ring. The second sealing end is a protruding end integrally formed on the sealing pressure ring.

6. The double-seal, double-discharge, triple-eccentric metal hard-seal butterfly valve according to claim 1, characterized in that: The valve seat and valve body are detachable. A valve seat pressure ring is provided on one side of the valve seat, and a three-part retaining ring is provided on the side of the valve seat pressure ring away from the valve seat. A retaining ring groove is provided on the valve body, and the three-part retaining ring is placed in the retaining ring groove. A set screw is provided on the three-part retaining ring, and the set screw passes through the three-part retaining ring to press and fix the valve seat pressure ring toward the valve seat.

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