A sealing assembly and sealing structure for a three-eccentric hard-sealed butterfly valve and a three-eccentric hard-sealed butterfly valve

Abstract

The sealing assembly for a triple-eccentric metal hard-sealed butterfly valve disclosed in the present invention comprises at least two metal sheets and at least two sealing rings made of non-metallic auxiliary materials, and is characterized in that an annular groove is provided on one surface of each metal sheet, and each sealing ring is embedded in the corresponding annular groove. The present invention also discloses a sealing structure comprising the sealing assembly and a triple-eccentric hard-sealed butterfly valve comprising the sealing structure. The present invention improves the reliability of the seal, and the seal is achieved by perfect metal to metal. The application of the sealing assembly of the present invention expands the application range of the triple-eccentric butterfly valve to any medium and high temperature, low temperature and harsh working conditions, and greatly extends the service life of the triple-eccentric seal.

Description

Technical Field

[0001] The invention relates to the technical field of triple-eccentric metal hard-sealed butterfly valves, and in particular to a sealing component and a sealing structure for a triple-eccentric metal hard-sealed butterfly valve and a triple-eccentric hard-sealed butterfly valve. Background Art

[0002] The butterfly valve was invented in the United States in the 1930s and is used in media transmission pipelines in urban construction, environmental protection, water conservancy, electricity, pharmaceuticals, petroleum, chemical industry, natural gas, nuclear power, offshore engineering, aerospace and other industries to cut off, throttle and regulate flow.

[0003] The three-eccentric hard-seal butterfly valve has gradually evolved from the centerline butterfly valve and the two-eccentric butterfly valve. Figures 1 to 3 The existing three-eccentric hard-sealed butterfly valve is mainly composed of a valve body 1, a valve plate 2, a valve stem 3, a valve plate sealing assembly 4, and a valve body sealing surface 5.

[0004] The three-eccentric hard-seal butterfly valve is a partial rotary valve system. Its switching process: when the valve stem 3 turns clockwise 0 0 -90 0 The valve position is closed. When the valve stem 3 rotates 90 degrees counterclockwise, 0 -0 0 The three eccentricities are as follows: Figure 4 It means adding an angular eccentricity on the basis of the double eccentric structure, so that the sealing surface of the butterfly valve is inclined conical. The characteristic of its structure is that the outer peripheral surface of the valve plate sealing component 4 is processed into an outer inclined conical surface, and the valve body sealing surface 5 is processed into an inner inclined conical surface. At this time, the sealing surface of the butterfly valve becomes an ellipse, and the shape of the valve plate sealing surface is therefore asymmetrical up and down. Since the sealing surface of the butterfly valve is an inclined cone, it is divided by the valve stem 3 axis into a larger side valve plate that presses upward toward the valve body along the large inclined curved surface, and a smaller side valve plate that presses downward toward the valve one along the small inclined curved surface. The seal between the valve plate sealing component 4 and the valve body sealing surface 5 is not based on the elastic deformation of the valve plate sealing component 4, but is completely based on the compression of the contact surface between the valve plate sealing component 4 and the valve body sealing surface 5 to achieve sealing. Therefore, the opening and closing of the three-eccentric butterfly valve is basically frictionless, and as the closing pressure increases, the valve becomes tighter and tighter.

[0005] With the development of modern industry, the application scope of three-eccentric hard-sealed butterfly valves is constantly expanding. The sealing components of existing three-eccentric hard-sealed butterfly valves are as follows: Figure 5 and Figure 6 The structure shown can no longer meet the requirements of the piping system conditions for the following reasons:

[0006] The sealing component 4 of the existing three-eccentric metal hard seal butterfly valve is as follows Figure 5 and Figure 6As shown, it is composed of three metal sheets 10, 20, 30 and non-metal auxiliary materials 40, 50. The non-metal auxiliary material 40 is arranged between the metal sheet 10 and the metal sheet 20, and the non-metal auxiliary material 50 is arranged between the metal sheet 20 and the metal sheet 30. Such a structure has the following problems:

[0007] 1. The metal sheets 10, 20, 30 are separated by non-metallic auxiliary materials 40, 50, so that the friction between the metal sheets 10, 20, 30 is increased.

[0008] 2. The end faces of the metal sheets 10, 20, 30 contact the valve body sealing surface 5 to form a seal, and the entrained metal auxiliary materials 40, 50 directly act on the sealing surface 5 to help the three-eccentric hard-sealed butterfly valve to play an auxiliary role in sealing performance in a short time or initial test. Figure 4 The three-eccentric characteristics of the three-eccentric hard-sealed butterfly valve, during the initial opening and closing process, the metal sheets 10, 20, 30 and the sealing surface 5 form forced friction (see Fig.18 ), which causes radial movement between the metal sheets, causing the metal auxiliary materials 40 and 50 between the metal sheets to fall off due to low material strength, directly affecting the sealing performance of the butterfly valve, and its name three-eccentric metal hard seal butterfly valve is not worthy of its name. When the valve is in the open state (see Fig.19 ), the metal auxiliary materials 40, 50 carried between the metal sheets will be washed by the medium in the pipeline and will also fall off, affecting the reliability of the seal. In addition, after the non-metallic auxiliary materials 40, 50 fall off, there will be gaps or cracks on the sealing surfaces between the metal sheets 10, 20, 30. Impurities in the pipeline medium are easy to fill the gaps and cracks to cause damage to the sealing components, thereby reducing the service life. Summary of the invention

[0009] One of the technical problems to be solved by the present invention is to provide a sealing assembly for a three-eccentric metal hard-sealed butterfly valve in response to the shortcomings of the valve plate sealing assembly used in the existing three-eccentric metal hard-sealed butterfly valve. The sealing assembly can achieve the sealing of the three-eccentric butterfly valve, realize complete metal-to-metal contact and reliable sealing, so that the butterfly valve can be used in a wider range of applications, such as in more severe working conditions such as high temperature and high pressure, and have a longer service life.

[0010] The second technical problem to be solved by the present invention is to provide a sealing structure including the above-mentioned sealing assembly.

[0011] The third technical problem to be solved by the present invention is to provide a three-eccentric hard-sealed butterfly valve including the above-mentioned sealing structure.

[0012] The sealing assembly for a three-eccentric metal hard-tight butterfly valve as the first aspect of the present invention comprises at least two metal sheets and at least two sealing rings made of non-metallic auxiliary materials. An annular groove is provided on one surface of each metal sheet, and each sealing ring is embedded in the corresponding annular groove.

[0013] In a preferred embodiment of the present invention, the metal sheets are stacked together along the axial direction of the metal sheets, and a sealing contact is formed between the outer surface of the sealing ring and the side of the adjacent metal sheet without the annular groove.

[0014] In a preferred embodiment of the present invention, the annular groove is provided on a side of the metal sheet away from the outer peripheral surface of the metal sheet.

[0015] In a preferred embodiment of the present invention, the outer peripheral surface of the metal sheet is processed into a bevel to form a hard sealing surface of the sealing assembly.

[0016] In a preferred embodiment of the present invention, the non-metallic auxiliary material is graphite and graphite products.

[0017] The sealing structure including the above-mentioned sealing assembly as the second aspect of the present invention also includes another hard sealing surface that cooperates with the hard sealing surface of the sealing assembly to perform sealing; the sealing assembly is arranged on the valve plate of the three-eccentric butterfly valve, and the other hard sealing surface is arranged on the valve body of the three-eccentric butterfly valve.

[0018] In a preferred embodiment of the present invention, the hard sealing surface of the sealing assembly is processed into an outer oblique conical surface, and the other hard sealing surface is processed into an inner oblique conical surface.

[0019] The sealing structure including the above-mentioned sealing assembly as the second aspect of the present invention also includes a hard sealing surface that cooperates with the hard sealing surface of the sealing assembly to perform sealing; the sealing assembly is arranged on the valve body of the three-eccentric butterfly valve, and the other hard sealing surface is arranged on the valve plate of the three-eccentric butterfly valve.

[0020] In a preferred embodiment of the present invention, the hard sealing surface of the sealing assembly is processed into an inner oblique conical surface, and the other hard sealing surface is processed into an outer oblique conical surface.

[0021] The sealing structure including the above-mentioned sealing assembly as the second aspect of the present invention includes the above-mentioned two groups of sealing assemblies, one group of sealing assemblies is arranged on the valve body of the three-eccentric butterfly valve, and the other group of sealing assemblies is arranged on the valve plate of the three-eccentric butterfly valve; the hard sealing surfaces of the two groups of sealing assemblies are in sealing contact.

[0022] In a preferred embodiment of the present invention, the hard sealing surface in the sealing assembly arranged on the valve plate of the triple eccentric butterfly valve is processed into an outer inclined conical surface, and the hard sealing surface in the sealing assembly arranged on the valve body of the triple eccentric butterfly valve is processed into an inner inclined conical surface.

[0023] A triple-eccentric hard-sealed butterfly valve as a third aspect of the present invention includes the above-mentioned sealing structure.

[0024] In a preferred embodiment of the present invention, the three-eccentric hard-sealed butterfly valve is a wafer-type three-eccentric hard-sealed butterfly valve, a flange-type three-eccentric hard-sealed butterfly valve, a lug-type three-eccentric hard-sealed butterfly valve, a lug-type three-eccentric hard-sealed butterfly valve or a welded three-eccentric hard-sealed butterfly valve.

[0025] Due to the adoption of the above technical solution, the present invention adopts a new structure of a sealing assembly formed by machining an annular groove on a metal sheet and placing a sealing ring made of a non-metallic sealing auxiliary material in the annular groove, which has the following beneficial effects compared with the prior art:

[0026] 1. The present invention adopts a new structure of a sealing assembly formed by machining an annular groove on a metal sheet and placing a sealing ring made of a non-metallic sealing auxiliary material in the annular groove. When the three-eccentric butterfly valve is under the action of the opening and closing force, the friction between the multiple metal sheets will be reduced, so that there is a slight string movement between the metal sheets, so that the hard sealing surface of the sealing assembly is easier to be close to another hard sealing surface (valve body sealing surface), thereby improving the sealing fit, truly forming a complete metal-to-metal contact and sealing, and making the sealing performance more reliable.

[0027] 2. The present invention adopts a new structure of a sealing component formed by processing an annular groove on a metal sheet and placing a sealing ring made of a non-metallic sealing auxiliary material in the annular groove. When the valve is in an open state, the medium in the pipe will not wash the sealing ring made of non-metallic auxiliary materials under the action of the flow rate, and will not cause the non-metallic auxiliary materials to fall off and directly affect the reliability of the seal. The non-metallic auxiliary materials will not fall off and cause gaps or cracks on the hard sealing surface, so that impurities in the pipeline medium will easily fill the gaps and cracks to cause damage to the sealing component, thereby improving the service life.

[0028] 3. The present invention improves the reliability of sealing, and the sealing is completely metal to metal. The application of the sealing assembly of the present invention expands the application range of the three-eccentric butterfly valve to any medium and high temperature, low temperature and severe working conditions, and greatly extends the service life of the three-eccentric hard-sealed butterfly valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of an existing three-eccentric hard-sealed butterfly valve.

[0030] Figure 2 The figure is a cross-sectional schematic diagram of an existing three-eccentric hard-sealed butterfly valve.

[0031] Figure 3 for Figure 2 An enlarged schematic diagram of point A.

[0032] Figure 4 The figure is a schematic diagram of the sealing principle of the existing three-eccentric hard-sealed butterfly valve.

[0033] Figure 5 The present invention is a structural schematic diagram of a valve plate sealing assembly of an existing triple eccentric metal hard seal butterfly valve.

[0034] Figure 6 for Figure 5 An enlarged schematic diagram of point A.

[0035] Figure 7 It is a schematic structural diagram of the sealing assembly of the present invention.

[0036] Figure 8 for Figure 7 An enlarged schematic diagram of point A.

[0037] Fig. 9 The figure is a schematic structural diagram of a triple-eccentric hard-sealed butterfly valve of the present invention.

[0038] Fig.10 The figure is a cross-sectional schematic diagram of a triple-eccentric hard-sealed butterfly valve of the present invention.

[0039] Fig.11 for Fig.10 An enlarged schematic diagram of point A.

[0040] Fig.12 The figure is a schematic structural diagram of another triple-eccentric hard-sealed butterfly valve of the present invention.

[0041] Fig.13 The figure is a cross-sectional schematic diagram of another triple-eccentric hard-sealed butterfly valve of the present invention.

[0042] Fig.14 for Fig.13 An enlarged schematic diagram of point A.

[0043] Fig.15 The figure is a schematic structural diagram of another triple-eccentric hard-sealed butterfly valve of the present invention.

[0044] Fig.16 The figure is a cross-sectional schematic diagram of another triple-eccentric hard-sealed butterfly valve of the present invention.

[0045] Fig.17 for Fig.16 An enlarged schematic diagram of point A.

[0046] Fig.18 It is a schematic diagram of an existing three-eccentric hard-sealed butterfly valve in a closed state.

[0047] Fig.19 It is a schematic diagram of an existing three-eccentric hard-sealed butterfly valve in an open state. DETAILED DESCRIPTION

[0048] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0049] See also Figure 7 and Figure 8 The sealing assembly 100 for the triple-eccentric metal hard-tight butterfly valve shown in the figure includes three metal sheets 110, 120, 130 and three sealing rings 140, 150, 160 made of non-metallic auxiliary materials. Of course, the number of metal sheets is not limited to three, and the number of sealing rings is not limited to three, and can be set according to the size of the butterfly valve.

[0050] An annular groove 112, 122, 132 is formed on one side 111, 121, 131 of the three metal sheets 110, 120, 130. The annular groove 112, 122, 132 is formed on one side of the metal sheets 110, 120, 130 away from the outer peripheral surface 113, 123, 133 of the metal sheets 110, 120, 130 respectively.

[0051] The three metal sheets 110 , 120 , 130 are stacked together along the axial direction of the metal sheets 110 , 120 , 130 , and the surfaces 111 , 121 , 131 of the three metal sheets 110 , 120 , 130 face the same direction.

[0052] The three sealing rings 140, 150, 160 are respectively embedded in the annular grooves 112, 122, 132 of the three metal sheets 110, 120, 130, the outer surface of the sealing ring 160 is in sealing contact with the surface 124 of the metal sheet 120, and the outer surface of the sealing ring 150 is in sealing contact with the surface 114 of the metal sheet 110. The outer surface of the sealing ring 140 is in contact with the valve or the valve body.

[0053] The outer peripheral surfaces 113, 123, 133 of the metal sheets 110, 120, 130 are processed into inclined surfaces to form hard sealing surfaces of the sealing assembly 100. The non-metallic auxiliary materials used to make the sealing rings 140, 150, 160 are graphite and graphite products.

[0054] Compared with the prior art, the sealing assembly 100 has the following beneficial effects:

[0055] 1. A new structure is adopted in which annular grooves 112, 122, 132 are machined on three metal sheets 110, 120, 130 and sealing rings 140, 150, 160 made of non-metallic sealing auxiliary materials are placed in the annular grooves 112, 122, 132 respectively. When the three-eccentric butterfly valve is under the action of the opening and closing force, the friction between the three metal sheets 110, 120, 130 will be reduced, so that there is a slight string movement between the metal sheets 110, 120, 130, so that the hard sealing surface of the sealing assembly 100 is easier to be close to another hard sealing surface (valve body sealing surface), thereby improving the sealing fit, truly forming a complete metal-to-metal contact and sealing, and making the sealing performance more reliable.

[0056] 2. A new structure is adopted in which annular grooves 112, 122, 132 are machined on three metal sheets 110, 120, 130 and sealing rings 140, 150, 160 made of non-metallic sealing auxiliary materials are placed in the annular grooves 112, 122, 132 respectively. When the valve is in the open state, the medium in the pipe will not wash the sealing rings 140, 150, 160 made of non-metallic auxiliary materials under the action of flow velocity, and will not cause the non-metallic auxiliary materials to fall off and directly affect the reliability of the seal. The non-metallic auxiliary materials will not fall off, causing gaps or cracks on the hard sealing surface, so that impurities in the pipeline medium are easily filled into the gaps and cracks to cause damage to the sealing component 100, thereby improving the service life.

[0057] 3. The reliability of the seal is improved, and the seal is completely formed by metal to metal. The application of the sealing assembly 100 expands the application range of the three-eccentric butterfly valve to any medium and high temperature, low temperature and severe working conditions, and greatly extends the service life of the three-eccentric seal.

[0058] The following is an application example of the sealing assembly 100 .

[0059] See also Figures 9 to 11 , a three-eccentric hard-sealed butterfly valve shown in the figure is mainly composed of a valve body 200, a valve plate 300, a valve stem 400, and a sealing assembly 100.

[0060] After the valve plate 300 is installed into the flow hole in the valve body 200, the valve stem 400 is inserted into the middle hole of the valve plate 300 and connected with a key or a pin.

[0061] The sealing assembly 100 is installed on the valve plate 300 using a pressing plate 600 and a pressing plate bolt 610, and the valve body embedded sealing seat 700 is installed on the valve body 200 using a valve body embedded sealing seat bolt 800, and a hard sealing surface 710 is provided on the valve body embedded sealing seat 700. The hard sealing surface 170 on the sealing assembly 100 is processed into an outer inclined conical surface, and the hard sealing surface 710 on the valve body embedded sealing seat 700 is processed into an inner inclined conical surface.

[0062] During sealing, the hard sealing surface 170 on the sealing assembly 100 and the hard sealing surface 710 on the valve body embedded sealing seat 700 realize a hard seal between metal and metal.

[0063] See also Figure 12 to Figure 14 , another triple eccentric hard-sealed butterfly valve shown in the figure is mainly composed of a valve body 200, a valve plate 300, a valve stem 400, and a sealing assembly 100a.

[0064] After the valve plate 300 is installed into the flow hole in the valve body 200, the valve stem 400 is inserted into the middle hole of the valve plate 300 and connected with a key or a pin.

[0065] The sealing assembly 100 a is installed on the valve body 200 by using a pressing plate 600 a , a threaded pressing plate 610 a and screws 620 a , and a hard sealing surface 310 is welded on the valve plate 300 .

[0066] The hard sealing surface 170a on the sealing assembly 100a is processed into an inner oblique conical surface, and the hard sealing surface 310 is processed into an inner oblique conical surface.

[0067] During sealing, the hard sealing surface 310 on the valve plate 300 and the hard sealing surface 170a on the sealing assembly 100a realize a hard seal between metal and metal.

[0068] See also Figures 15 to 17 , another triple-eccentric hard-sealed butterfly valve shown in the figure is mainly composed of a valve body 200, a valve plate 300, a valve stem 400, and a sealing assembly 100.

[0069] After the valve plate 300 is installed into the flow hole in the valve body 200, the valve stem 400 is inserted into the middle hole of the valve plate 300 and connected with a key or a pin.

[0070] The sealing assembly 100 is installed on the valve plate 300 using a pressure plate 600 and a pressure plate bolt 610, and a hard sealing surface 210 is welded on the sealing surface of the valve body 200. The hard sealing surface 170 on the sealing assembly 100 is processed into an outer inclined cone surface, and the hard sealing surface 210 is processed into an inner inclined cone surface.

[0071] During sealing, the hard sealing surface 170 and the hard sealing surface 210 on the sealing assembly 100 realize a hard seal between metal and metal.

[0072] The above-mentioned three-eccentric hard-sealed butterfly valve is a wafer-type three-eccentric hard-sealed butterfly valve, a flange-type three-eccentric hard-sealed butterfly valve, a lug-type three-eccentric hard-sealed butterfly valve, a lug-type three-eccentric hard-sealed butterfly valve or a welded three-eccentric hard-sealed butterfly valve.

Claims

1. A sealing assembly for a triple eccentric metal hard-tight butterfly valve, comprising at least two metal sheets and at least two sealing rings made of non-metallic auxiliary materials, characterized in that: An annular groove is provided on one surface of each metal sheet, and each sealing ring is embedded in the corresponding annular groove; The metal sheets are stacked together along the axial direction of the metal sheets, and the sides of the metal sheets with the annular grooves are oriented in the same direction; the outer surface of the sealing ring forms a sealing contact with the side of the adjacent metal sheet without the annular grooves; The annular groove is disposed on a side of the metal sheet away from the outer peripheral surface of the metal sheet; The outer peripheral surface of the metal sheet is processed into an inclined surface to form a hard sealing surface of the sealing component.

2. The sealing assembly for a triple eccentric metal hard-tight butterfly valve according to claim 1, characterized in that: The non-metallic auxiliary materials are graphite and graphite products.

3. A sealing structure comprising the sealing assembly according to claim 1 or 2, characterized in that: It also comprises another hard sealing surface which cooperates with the hard sealing surface of the sealing component to perform sealing; the sealing component is arranged on the valve plate of the three-eccentric butterfly valve, and the other hard sealing surface is arranged on the valve body of the three-eccentric butterfly valve.

4. The sealing structure according to claim 3, characterized in that: The hard sealing surface of the sealing component is processed into an outer oblique cone surface, and the other hard sealing surface is processed into an inner oblique cone surface.

5. A sealing structure comprising the sealing assembly according to claim 1 or 2, characterized in that: It also comprises another hard sealing surface which cooperates with the hard sealing surface of the sealing component to perform sealing; the sealing component is arranged on the valve body of the three-eccentric butterfly valve, and the other hard sealing surface is arranged on the valve plate of the three-eccentric butterfly valve.

6. The sealing structure according to claim 5, characterized in that: The hard sealing surface of the sealing component is processed into an inner oblique cone surface, and the other hard sealing surface is processed into an outer oblique cone surface.

7. A sealing structure comprising the sealing assembly according to claim 1 or 2, characterized in that: It comprises two sets of the above-mentioned sealing components, one set of sealing components is arranged on the valve body of the three-eccentric butterfly valve, and the other set of sealing components is arranged on the valve plate of the three-eccentric butterfly valve; the hard sealing surfaces of the two sets of sealing components are in sealing contact.

8. The sealing structure according to claim 7, characterized in that: The hard sealing surface of the sealing assembly arranged on the valve plate of the triple eccentric butterfly valve is processed into an outer oblique conical surface, and the hard sealing surface of the sealing assembly arranged on the valve body of the triple eccentric butterfly valve is processed into an inner oblique conical surface. 9.Triple eccentric hard seal butterfly valve, characterized in that: A sealing structure comprising any one of claims 3 to 8.

10. The triple eccentric hard-sealed butterfly valve according to claim 9, characterized in that: The three-eccentric hard-sealed butterfly valve is a wafer-type three-eccentric hard-sealed butterfly valve, a flange-type three-eccentric hard-sealed butterfly valve, a lug-type three-eccentric hard-sealed butterfly valve or a lug-type three-eccentric hard-sealed butterfly valve.

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