Eccentric C-shaped ball valve

Abstract

The invention relates to the technical field of valves, and discloses an eccentric C-shaped ball valve which comprises a valve body, a valve cover, a valve seat, a ball body, a valve rod and a sealing ring assembly. The valve cover is also provided with a flow channel, and the valve seat is installed on the valve cover; the ball body is movably arranged in the valve body; one end of the valve rod extends into the valve body to be connected with the ball body, the sealing ring assembly is installed on the ball body, and the sealing ring assembly is configured to deform when abutting against the sealing face on the valve seat. The sealing ring assembly and the valve seat are adopted for sealing, the sealing ring assembly and the ball body are machined independently, the machining difficulty and machining cost of the ball body are reduced, meanwhile, due to the fact that the sealing ring assembly is configured to deform when abutting against the upper sealing face of the valve seat, the applicability of the sealing ring assembly is higher, and the service life of the sealing ring assembly is prolonged. The sealing ring assembly and the valve seat sealing face do not need independent match grinding.

Description

Technical Field

[0001] The invention relates to the technical field of valves, in particular to an eccentric C-type ball valve. Background Art

[0002] The eccentric C-type ball valve (also known as "eccentric hemispherical valve") is a valve in which the center axis of the valve shaft is eccentric to the center line of the hemispherical body (C-type sphere), and a sealing pair is only provided on one side of the valve body.

[0003] Common eccentric C-type ball valves are mainly hard-sealed, and the ball sealing surface and the ball are generally designed as an integrated design. The ball sealing surface is hardened (supersonic spraying, thermal spray welding, etc.), machined, and ground to form a sealing pair with the valve seat. However, in the above design, the ball sealing surface and the ball are integrated, and the process difficulty and cost are high during processing and grinding. For this reason, Chinese patent document CN203009893U discloses an eccentric semi-ball valve, which shows a split design scheme for the ball sealing surface. This patent scheme only reduces the difficulty and cost of ball processing to a certain extent, but the ball crown is an integral rigid part. The sealing surface on the ball crown and the sealing surface on the valve seat form a sealing pair. Therefore, in order to achieve better sealing performance, the ball crown and the ball crown sealing surface not only have high processing and installation positioning accuracy requirements, but the ball crown and the valve seat sealing surface still need to be ground separately. Standardized production and universal assembly of ball crowns and valve seats cannot be achieved. Summary of the invention

[0004] In view of this, the present invention provides an eccentric C-type ball valve to solve the problem that the ball crown and the valve seat sealing surface need to be ground separately.

[0005] In the first aspect, the present invention provides an eccentric C-type ball valve, including a valve body, a valve cover, a valve seat, a sphere, a valve stem and a sealing ring assembly, wherein the valve body has a cavity and a flow channel connected to the cavity; the valve cover is connected to the valve body; the valve cover is also provided with a flow channel, and the flow channel is suitable for communicating with the cavity; the valve seat is installed on the valve cover, and the valve seat is located at the flow channel opening inside the valve cover; a sealing surface is provided on the valve seat; the sphere is movably arranged inside the valve body; one end of the valve stem extends into the interior of the valve body and is connected to the sphere, and the other end of the valve stem is located outside the valve body, and the sealing ring assembly is installed on the sphere, the sealing ring assembly moves synchronously with the sphere to the valve seat and abuts against the sealing surface on the valve seat through the sealing ring assembly, or the sealing ring assembly moves synchronously with the sphere to separate the sealing ring assembly from the sealing surface on the valve seat, wherein the sealing ring assembly is configured to deform when abutting against the sealing surface on the valve seat.

[0006] Beneficial effects: In order to solve the problem that the ball crown and the valve seat sealing surface need to be ground separately, the present invention is provided with a sealing ring assembly, which is installed on the ball. Compared with the conventional sealing between the ball and the valve seat, the present invention uses a sealing ring assembly to seal with the valve seat. The sealing ring assembly and the ball are processed independently, which reduces the difficulty and cost of ball processing. At the same time, because the sealing ring assembly is configured to deform when it abuts against the sealing surface on the valve seat, the sealing ring assembly has higher applicability, and the sealing ring assembly and the valve seat sealing surface do not need to be ground separately. Parts can be standardized and universally assembled, which can not only significantly reduce production costs and production difficulties, shorten the production cycle, but also meet the requirements of rapid response during valve maintenance.

[0007] In an optional embodiment, the sealing ring assembly includes a plurality of metal sealing rings and a plurality of graphite sealing rings, the metal sealing rings and the graphite sealing rings are alternately stacked, and the metal sealing rings are located at the outermost side.

[0008] Beneficial effects: Metal sealing rings have good strength and corrosion resistance, and can withstand high pressure and harsh working environment; graphite sealing rings have excellent self-lubrication and sealing performance, and can effectively fill the sealing gap and reduce leakage. The metal sealing rings and graphite sealing rings are staggered and stacked. This unique stacking method fully combines the advantages of metal and graphite, and gives full play to the synergistic effect of the two. The metal sealing ring provides structural support and strength guarantee, while the graphite sealing ring focuses on improving the sealing performance. The metal sealing ring is on the outermost side. This layout design has multiple advantages. On the one hand, the metal sealing ring can directly resist external impact, wear and chemical erosion, and protect the internal graphite sealing ring; on the other hand, the rigidity of the metal sealing ring can ensure that the entire sealing ring assembly maintains a stable shape and structure during installation and use. During operation, when the sealing ring assembly is under pressure, the metal sealing ring, with its high strength and rigidity, evenly distributes the pressure to each graphite sealing ring. The graphite sealing ring is slightly deformed under pressure, so that it fits the valve seat sealing surface better, thereby achieving a good sealing effect. At the same time, the self-lubricating property of the graphite sealing ring can reduce the friction between the sealing ring and the sealing surface of the valve seat, reduce wear and extend the service life of the sealing ring assembly.

[0009] In an optional embodiment, the inner diameter of the graphite sealing ring is larger than the inner diameter of the metal sealing ring, and all the metal sealing rings are provided with a positioning portion, and the positioning portion avoids the graphite sealing ring. The eccentric C-type ball valve also includes an anti-rotation member, which is connected to the ball and adapted to the positioning portion to limit the rotation of the sealing ring assembly.

[0010] Beneficial effect: The inner diameter of the graphite sealing ring is larger than the inner diameter of the metal sealing ring. This design provides space conditions for setting a positioning part on the metal sealing ring later. Specifically, the positioning part is set on the metal sealing ring and avoids the graphite sealing ring. When the anti-rotation part is connected to the positioning part, since the positioning part avoids the graphite sealing ring, it can effectively prevent the anti-rotation part from causing damage to the graphite sealing ring due to contact or collision during installation or operation. The graphite sealing ring has good self-lubricity and high temperature resistance. It is a key component to ensure the normal operation of the valve under extreme working conditions such as high temperature and high pressure. Protecting it can greatly extend the service life and maintenance cycle of the valve.

[0011] In an optional embodiment, the positioning portion is a notch provided on the inner ring surface of the metal sealing ring or a through hole provided on the metal sealing ring.

[0012] In an optional embodiment, an annular groove is provided on the sphere, and the sealing ring assembly is placed in the annular groove; the eccentric C-type ball valve also includes a pressure ring connected to the sphere, and the pressure ring abuts against the sealing ring assembly and limits the movement of the sealing ring assembly.

[0013] Beneficial effects: An annular groove is provided on the sphere, and the sealing ring assembly is placed in the annular groove. This design provides a precise installation position for the sealing ring assembly, ensures its stability on the sphere, and makes the sealing ring assembly fit closely with the sphere, effectively playing a sealing role during the opening and closing process of the ball valve. The pressure ring abuts against the sealing ring assembly. The role of the pressure ring is crucial. It abuts closely against the sealing ring assembly to limit the movement of the sealing ring assembly, ensuring that the sealing ring assembly is always in the correct position during the operation of the ball valve, and will not be displaced due to pressure fluctuations or sphere movement, thereby ensuring good sealing performance.

[0014] In an optional embodiment, the eccentric C-type ball valve further includes a graphite gasket, and the graphite gasket is clamped and fixed between the annular groove wall and the sealing ring assembly.

[0015] Beneficial effects: The graphite gasket is soft and has good compressibility and resilience. When the sealing ring assembly is installed in the annular groove, the graphite gasket is tightly squeezed between the two, filling the slight gap that may exist between the sealing ring assembly and the annular groove wall, further enhancing the tightness of the seal.

[0016] In an optional embodiment, the graphite gasket is confined in a limiting groove provided on the wall of the annular groove.

[0017] Beneficial effect: The graphite gasket is clamped and fixed between the annular groove wall and the sealing ring assembly, and is confined in the limiting groove provided on the annular groove wall. The shape and size of the limiting groove are precisely matched with the graphite gasket, and the graphite gasket can be tightly embedded in the limiting groove during installation. This not only prevents the graphite gasket from being displaced or falling off when the sealing ring assembly is working, but also further enhances the fit between the graphite gasket and the annular groove wall, making it more effective in filling the fine gap between the sealing ring assembly and the annular groove wall.

[0018] In an optional embodiment, the eccentric C-type ball valve further includes a stem packing, a pressure plate and a nut, wherein the stem packing is filled in the gap between the valve body and the valve stem; the lower end of the pressure plate is in the gap between the valve body and the valve stem and abuts against the stem packing, and the nut passes through the upper end of the pressure plate and is connected to the valve body. The stem packing is filled in the gap between the valve body and the valve stem.

[0019] In an optional embodiment, the eccentric C-type ball valve further includes a pivot, and the upper end of the pivot passes through the bottom of the valve body and is suitable for rotationally connecting with the bottom of the ball body.

[0020] The eccentric C-type ball valve provided by the present invention has the following advantages:

[0021] 1. The eccentric C-type ball valve provided by the present invention can realize standardized production and universal assembly of all parts such as the ball, sealing ring assembly, and valve seat. It can not only significantly reduce the production cost and difficulty of the valve, but also shorten the production cycle. At the same time, it can meet the rapid response requirements during valve maintenance.

[0022] 2. The eccentric C-type ball valve provided by the present invention uses a graphite gasket to seal between the bottom of the sealing ring assembly and the ball. The sealing ring assembly is also made of metal and graphite materials. It can meet the high temperature and corrosion resistance requirements under most working conditions.

[0023] 3. The eccentric C-type ball valve provided by the present invention, the corrosion resistance and wear resistance of the metal sealing ring, the self-lubricating property of the graphite sealing ring, and the guarantee of the stability of the sealing ring assembly by various components jointly ensure its stability and reliability during long-term use, reducing maintenance and replacement costs. The stabilizing effect of the limit groove on the graphite gasket and the anti-loosening effect of the spring washer on the screw further improve the durability of the entire assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 This is a schematic structural diagram of an eccentric C-type ball valve according to an embodiment of the present invention;

[0026] Figure 2 for Figure 1 A is a partial enlarged schematic diagram;

[0027] Figure 3 This is a schematic structural diagram of a sealing ring assembly in an eccentric C-type ball valve according to an embodiment of the present invention;

[0028] Figure 4 The present invention is a cross-sectional view of a sealing ring assembly in an eccentric C-type ball valve according to an embodiment of the present invention.

[0029] Description of reference numerals:

[0030] 1. Valve body; 2. Valve cover; 3. Valve seat; 4. Ball; 5. Valve stem; 61. Metal sealing ring; 611. Positioning part; 62. Graphite sealing ring; 7. Anti-rotation part; 8. Pressing ring; 9. Graphite gasket; 10. Valve stem packing; 11. Pressing plate; 12. Gland flange; 13. Pivot. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0032] The eccentric C-type ball valve (also known as "eccentric hemispherical valve") is a valve in which the center axis of the valve shaft is eccentric to the center line of the hemispherical body (C-type sphere), and a sealing pair is only provided on one side of the valve body.

[0033] Common eccentric C-type ball valves are mainly hard-sealed, and the ball sealing surface and the ball are generally designed as an integrated design. The ball sealing surface is hardened (supersonic spraying, thermal spray welding, etc.), machined, and ground to form a sealing pair with the valve seat. However, in the above design, the ball sealing surface and the ball are integrated, and the process difficulty and cost are high during processing and grinding. For this reason, Chinese patent document CN203009893U discloses an eccentric semi-ball valve, which shows a split design scheme for the ball sealing surface. This patent scheme only reduces the difficulty and cost of ball processing to a certain extent, but the ball crown is an integral rigid part. The sealing surface on the ball crown and the sealing surface on the valve seat form a sealing pair. Therefore, in order to achieve better sealing performance, the ball crown and the ball crown sealing surface not only have high processing and installation positioning accuracy requirements, but the ball crown and the valve seat sealing surface still need to be ground separately. Standardized production and universal assembly of ball crowns and valve seats cannot be achieved.

[0034] Combine the following Figures 1 to 4 , describing an embodiment of the present invention.

[0035] According to an embodiment of the present invention, an eccentric C-type ball valve is provided. Figure 1 As shown, it includes a valve body 1, a valve cover 2, a valve seat 3, a ball 4, a valve stem 5 and a sealing ring assembly, the valve body 1 has a cavity and a flow channel connected to the cavity; the valve cover 2 is connected to the valve body 1; the valve cover 2 is also provided with a flow channel, which is suitable for communicating with the cavity; the valve seat 3 is installed on the valve cover 2, and the valve seat 3 is located at the flow channel opening inside the valve cover 2; a sealing surface is provided on the valve seat 3; the ball 4 is movably arranged inside the valve body 1; one end of the valve stem 5 extends into the interior of the valve body 1 and is connected to the ball 4, and the other end of the valve stem 5 is outside the valve body 1; the sealing ring assembly is installed on the ball 4, the sealing ring assembly and the ball 4 move synchronously to the valve seat 3 and abut against the sealing surface on the valve seat 3 through the sealing ring assembly, or the sealing ring assembly and the ball 4 move synchronously to separate the sealing ring assembly and the sealing surface on the valve seat 3, wherein the sealing ring assembly is configured to produce elastic deformation when abutting against the sealing surface on the valve seat 3.

[0036] In order to solve the problem that the sealing surface of the ball crown and the valve seat 3 needs to be ground separately, a sealing ring assembly is provided in this embodiment, and the sealing ring assembly is installed on the ball 4. Compared with the conventional sealing with the valve seat 3 through the ball 4, the sealing ring assembly and the valve seat 3 are used in this embodiment to seal. The processing of the sealing ring assembly and the ball 4 is independent of each other, which reduces the processing difficulty and processing cost of the ball 4. At the same time, because the sealing ring assembly is configured to deform when it abuts against the sealing surface on the valve seat 3, the applicability of the sealing ring assembly is higher, and the sealing ring assembly and the sealing surface of the valve seat 3 do not need to be ground separately. Parts can be standardized and universally assembled, which can not only significantly reduce production costs and production difficulties, shorten the production cycle, but also meet the rapid response requirements during valve maintenance.

[0037] In this embodiment, the sealing ring assembly is fixed on the ball 4 to ensure that the sealing ring assembly can rotate synchronously with the ball 4. When the eccentric C-type ball valve needs to be closed, the ball 4 is driven to rotate synchronously by rotating the valve stem 5, and the sealing ring assembly and the ball 4 move synchronously to the valve seat 3 and abut the sealing surface on the valve seat 3 through the sealing ring assembly to close the eccentric C-type ball valve. Similarly, when the eccentric C-type ball valve needs to be opened, the ball 4 is driven to rotate synchronously by rotating the valve stem 5, and the sealing ring assembly and the ball 4 move synchronously to separate the sealing ring assembly from the sealing surface on the valve seat 3 to open the eccentric C-type ball valve.

[0038] In one embodiment, Figures 2 to 4As shown, the sealing ring assembly includes a plurality of metal sealing rings 61 and a plurality of graphite sealing rings 62, and the metal sealing rings 61 and the graphite sealing rings 62 are stacked alternately, and the metal sealing rings 61 are at the outermost side. The metal sealing rings 61 have good strength and corrosion resistance, and can withstand high pressure and harsh working environment; the graphite sealing rings 62 have excellent self-lubrication and sealing properties, and can effectively fill the sealing gap and reduce leakage. The metal sealing rings 61 and the graphite sealing rings 62 are stacked alternately. This unique stacking method fully combines the advantages of metal and graphite, and gives play to the synergistic effect of the two. The metal sealing rings 61 provide structural support and strength guarantee, and the graphite sealing rings 62 focus on improving the sealing performance. The metal sealing rings 61 are at the outermost side. This layout design has multiple advantages. On the one hand, the metal sealing rings 61 can directly resist external impact, wear and chemical erosion, and protect the internal graphite sealing rings 62; on the other hand, the rigidity of the metal sealing rings 61 can ensure that the entire sealing ring assembly maintains a stable shape and structure during installation and use. During operation, when the sealing ring assembly is subjected to pressure, the metal sealing ring 61, with its high strength and rigidity, evenly distributes the pressure to each graphite sealing ring 62. The graphite sealing ring 62 is slightly deformed under the pressure, so that it better fits the sealing surface of the valve seat 3, thereby achieving a good sealing effect. At the same time, the self-lubricating property of the graphite sealing ring 62 can reduce the friction between the sealing ring and the sealing surface of the valve seat 3, reduce wear, and extend the service life of the sealing ring assembly.

[0039] In one embodiment, the inner diameter of the graphite sealing ring 62 is larger than the inner diameter of the metal sealing ring 61, and all metal sealing rings 61 are provided with a positioning portion 611, and the positioning portion 611 avoids the graphite sealing ring 62. The eccentric C-type ball valve also includes an anti-rotation member 7, which is connected to the ball 4 and adapted to the positioning portion 611 to limit the rotation of the sealing ring assembly.

[0040] The inner diameter of the graphite sealing ring 62 is larger than the inner diameter of the metal sealing ring 61. This design provides space conditions for subsequently setting the positioning portion 611 on the metal sealing ring 61. Specifically, the positioning portion 611 is set on the metal sealing ring 61 and avoids the graphite sealing ring 62. When the anti-rotation part 7 is connected to the positioning portion 611, since the positioning portion 611 avoids the graphite sealing ring 62, it can effectively prevent the anti-rotation part 7 from causing damage to the graphite sealing ring 62 due to contact or collision during installation or operation. The graphite sealing ring 62 has good self-lubricity and high temperature resistance. It is a key component to ensure the normal operation of the valve under extreme working conditions such as high temperature and high pressure. Protecting it can greatly extend the service life and maintenance cycle of the valve.

[0041] At the same time, as one of the core components of the entire ball valve structure, the anti-rotation component 7 is tightly connected to the ball 4 and accurately fits the positioning part 611. In the dynamic process of opening and closing the valve, the rotation of the ball 4 will drive the entire sealing assembly to work in coordination. At this time, the anti-rotation component 7 plays a vital role. It can effectively limit the rotation of the sealing ring assembly. This function not only ensures that the sealing ring is always in the preset correct position during operation and maintains a stable and reliable sealing state, but also avoids the problem of uneven wear of the sealing surface caused by the rotation of the sealing ring. Uneven wear of the sealing surface will reduce the sealing performance and increase the risk of leakage. The application of the anti-rotation component 7 effectively solves this potential hidden danger and further improves the reliability and stability of the valve.

[0042] Specifically, the positioning portion 611 is a notch provided on the inner surface of the metal sealing ring 61 or a through hole provided on the metal sealing ring 61. Figure 3 In the structure shown, the positioning portion 611 is a notch provided on the inner ring surface of the metal sealing ring 61, and the notch is semicircular. The size of the notch is precisely matched according to the size of the anti-rotation member 7, ensuring that the two can fit closely and will not cause installation difficulties or damage to components due to excessive interference. The anti-rotation member 7 is a slightly shaped member, and a slot for inserting the anti-rotation member 7 is provided on the sphere 4. After the sealing ring assembly is installed on the sphere 4, the anti-rotation member 7 is inserted into the positioning portion 611 on the sealing ring assembly and then inserted into the slot on the sphere 4, thereby limiting the sealing ring assembly, ensuring that the sealing ring is always in the preset correct position during operation, maintaining a stable and reliable sealing state, and avoiding the problem of uneven wear of the sealing surface caused by the rotation of the sealing ring. Alternatively, when the anti-rotation member 7 is a through hole provided on the metal sealing ring 61, these through holes penetrate the metal sealing ring 61, and the aperture size thereof is determined according to the size of the anti-rotation member 7 to ensure the firmness of the connection.

[0043] In one embodiment, a plurality of positioning portions 611 may be provided, usually in a circular array or symmetrically distributed manner, so that when the anti-rotation member 7 is connected to the metal sealing ring 61, the force can be evenly transmitted to the entire sealing ring, effectively preventing the sealing ring from having local stress concentration during the movement of the ball 4. By connecting the anti-rotation member 7 to the through hole on the metal sealing ring 61, not only can the rotation of the sealing ring assembly be restricted, but also the structural strength of the metal sealing ring 61 can be enhanced to a certain extent, thereby improving its ability to resist external impact.

[0044] In one embodiment, an annular groove is provided on the ball 4, and the sealing ring assembly is placed in the annular groove; the eccentric C-type ball valve also includes a pressure ring 8, which is connected to the ball 4, and the pressure ring 8 abuts against the sealing ring assembly and restricts the movement of the sealing ring assembly. An annular groove is provided on the ball 4, and the sealing ring assembly is just placed in the annular groove. This design provides a precise installation position for the sealing ring assembly, ensures its stability on the ball 4, and makes the sealing ring assembly fit closely with the ball 4, so as to effectively play a sealing role during the opening and closing process of the ball valve.

[0045] The pressure ring 8 is in contact with the sealing ring assembly. The pressure ring 8 plays a vital role. It closely contacts the sealing ring assembly to limit the movement of the sealing ring assembly, ensuring that the sealing ring assembly is always in the correct position during the operation of the ball valve and will not be displaced due to pressure fluctuations or movement of the ball 4, thereby ensuring good sealing performance.

[0046] In one embodiment, Figure 2 As shown, the eccentric C-type ball valve also includes a graphite gasket 9, which is clamped and fixed between the annular groove wall and the sealing ring assembly. The graphite gasket 9 is soft and has good compressibility and resilience. When the sealing ring assembly is installed in the annular groove, the graphite gasket 9 is tightly squeezed between the two, filling the possible slight gap between the sealing ring assembly and the annular groove wall, further enhancing the tightness of the seal.

[0047] In one embodiment, the graphite gasket 9 is confined in a limiting groove provided on the annular groove wall. The graphite gasket 9 is clamped and fixed between the annular groove wall and the sealing ring assembly, and is confined in the limiting groove provided on the annular groove wall. The shape and size of the limiting groove are precisely matched with the graphite gasket 9, and the graphite gasket 9 can be tightly embedded in the limiting groove during installation. This not only prevents the graphite gasket 9 from being displaced or falling off when the sealing ring assembly is working, but also further enhances the fit between the graphite gasket 9 and the annular groove wall, making it more effective in filling the fine gap between the sealing ring assembly and the annular groove wall.

[0048] In one embodiment, the pressure ring 8 is fixed to the ball 4 via screws, and a spring washer is provided on the screws.

[0049] In one embodiment, Figure 1As shown, the eccentric C-type ball valve also includes a stem packing 10, a pressure plate 11 and a nut. The stem packing 10 is filled in the gap between the valve body 1 and the valve stem 5; the lower end of the pressure plate 11 is in the gap between the valve body 1 and the valve stem 5 and abuts the stem packing 10, and the nut passes through the upper end of the pressure plate 11 and is connected to the valve body 1. The stem packing 10 is filled in the gap between the valve body 1 and the valve stem 5. The stem packing 10 is usually made of materials with good sealing performance and corrosion resistance, such as polytetrafluoroethylene, rubber, etc. It is soft and has a certain elasticity, can fit the surface of the valve stem 5 and the valve body 1 tightly, and effectively prevent the medium from leaking along the gap between the valve stem 5 and the valve body 1. The lower end of the pressure plate 11 is in the gap between the valve body 1 and the valve stem 5 and abuts the stem packing 10. The pressure plate 11 plays a role in applying pressure to the stem packing 10. By adjusting the degree of compression of the pressure plate 11 on the stem packing 10, the sealing effect can be effectively controlled. The pressure plate 11 is generally made of metal and has sufficient strength and rigidity to ensure that it can stably apply pressure to the valve stem packing 10 during operation. The nut passes through the upper end of the pressure plate 11 and is connected to the valve body 1. By rotating the nut, the pressing force of the pressure plate 11 on the valve stem packing 10 can be adjusted. During installation, it is necessary to tighten the nut appropriately according to the actual working conditions and sealing requirements so that the pressure plate 11 can evenly press the valve stem packing 10 to achieve a good sealing effect. At the same time, the tightening of the nut also requires attention to the strength to avoid excessive compression of the valve stem packing 10 due to over-tightening, which affects the normal rotation of the valve stem 5, or a decrease in sealing performance due to over-loosening.

[0050] In one embodiment, Figure 1 As shown, the eccentric C-type ball valve also includes a pivot 13, and the upper end of the pivot 13 passes through the bottom of the valve body 1 and is suitable for rotationally connecting with the bottom of the ball 4. The pivot 13 is usually made of high-strength alloy steel and has good wear resistance and fatigue resistance. A mounting hole adapted to the pivot 13 is provided at the bottom of the valve body 1, and the upper end of the pivot 13 is precisely machined to ensure the connection accuracy with the bottom of the ball 4. A special connection structure, such as a boss, is designed at the bottom of the ball 4, which is tightly matched with the upper end of the pivot 13. A bearing is provided between the upper end of the pivot 13 and the ball 4, so that the ball 4 can flexibly rotate around the pivot 13 to realize the opening and closing action of the ball valve.

[0051] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. An eccentric C-type ball valve, comprising: A valve body (1) having a cavity and a flow channel communicating with the cavity; A valve cover (2) is connected to the valve body (1); a flow channel is also provided on the valve cover (2), and the flow channel is suitable for communicating with the cavity; A valve seat (3) is mounted on the valve cover (2), and the valve seat (3) is located at the flow passage opening inside the valve cover (2); a sealing surface is provided on the valve seat (3); A ball (4) movably arranged inside the valve body (1); A valve stem (5), one end of which extends into the interior of the valve body (1) and is connected to the ball (4), and the other end of the valve stem (5) is located outside the valve body (1); The invention is characterized in that it also comprises a sealing ring assembly mounted on the ball (4), wherein the sealing ring assembly and the ball (4) move synchronously to the valve seat (3) and abut against the sealing surface on the valve seat (3) through the sealing ring assembly, or the sealing ring assembly and the ball (4) move synchronously to separate the sealing ring assembly from the sealing surface on the valve seat (3); Wherein, the sealing ring assembly is configured to deform when it abuts against the sealing surface on the valve seat (3).

2. The eccentric C-type ball valve according to claim 1, characterized in that: The sealing ring assembly comprises a plurality of metal sealing rings (61) and a plurality of graphite sealing rings (62); the metal sealing rings (61) and the graphite sealing rings (62) are stacked in an alternating manner, and the metal sealing rings (61) are located at the outermost side.

3. The eccentric C-type ball valve according to claim 2, characterized in that: The inner diameter of the graphite sealing ring (62) is greater than the inner diameter of the metal sealing ring (61); a positioning portion (611) is provided on each of the metal sealing rings (61), and the positioning portion (611) avoids the graphite sealing ring (62); It also includes an anti-rotation component (7), which is connected to the ball (4) and adapted to the positioning portion (611) to limit the rotation of the sealing ring assembly.

4. The eccentric C-type ball valve according to claim 3, characterized in that: The positioning portion (611) is a notch provided on the inner ring surface of the metal sealing ring (61) or a through hole provided on the metal sealing ring (61).

5. The eccentric C-type ball valve according to any one of claims 1 to 4, characterized in that: The spherical body (4) is provided with an annular groove, and the sealing ring assembly is placed in the annular groove; It also includes a pressure ring (8) connected to the ball (4), and the pressure ring (8) abuts against the sealing ring assembly and limits the movement of the sealing ring assembly.

6. The eccentric C-type ball valve according to claim 5, characterized in that: It also comprises a graphite gasket (9), which is clamped and fixed between the annular groove wall and the sealing ring assembly.

7. The eccentric C-type ball valve according to claim 6, characterized in that: The graphite gasket (9) is confined in a limiting groove provided on the wall of the annular groove.

8. The eccentric C-type ball valve according to claim 5, characterized in that: The pressure ring (8) is fixed to the sphere (4) via screws, and a spring washer is provided on the screws.

9. The eccentric C-type ball valve according to any one of claims 1 to 4, characterized in that: Also includes: A valve stem filler (10) is filled in the gap between the valve body (1) and the valve stem (5); A pressure plate (11), the lower end of which is located in the gap between the valve body (1) and the valve stem (5) and abuts against the valve stem packing (10); A nut passes through the upper end of the pressure plate (11) and is connected to the valve body (1).

10. The eccentric C-type ball valve according to claim 9, characterized in that: It also comprises a pivot (13), the upper end of which passes through the bottom of the valve body (1) and is suitable for being rotatably connected to the bottom of the ball (4).

Images