Wearing C type ball valve

Abstract

The application discloses a top-mounted C-type wear-resistant ball valve, which comprises a valve body, a valve cover, a C-type ball body, a valve rod, a left valve seat assembly, a right valve seat assembly, a stuffing box assembly and a driving connection support; the valve body is of an integral casting structure, is provided with flange connection ends at both ends, and a spherical valve cavity is formed in the valve body; the valve cover is fixedly connected at a top opening of the valve body through a plurality of bolt and nut assemblies; the C-type ball body is rotatably arranged in the spherical valve cavity, an upper portion of the C-type ball body is provided with a connecting groove matched with a lower end of the valve rod; a blowdown opening communicated with the lowest part of the valve cavity is arranged at the bottom of the valve body, and a detachable blowdown plug is arranged, so that solid particles and impurities deposited in the valve cavity can be completely discharged regularly, ball body jamming and abnormal wear of a sealing surface caused by deposition of the solid particles and the impurities are avoided, and long-term stable operation of the valve under a solid particle-containing medium working condition is effectively ensured.

Description

Technical Field

[0001] This invention relates to wear-resistant ball valves, and more particularly to top-mounted C-type wear-resistant ball valves. Background Technology

[0002] C-type ball valves, as a type of rotary shut-off valve, are widely used in industries such as coal chemical, mining, power, metallurgy, and building materials due to their smooth flow path, large flow capacity, and rapid opening and closing. They are mainly used in pipeline systems that transport abrasive media such as solid particles, dust, slurry, and ash to achieve on / off control and flow regulation of the media.

[0003] With the increasing demands for valve reliability and service life in industrial production, traditional C-type ball valves have gradually revealed many shortcomings in practical applications: Firstly, most existing C-type ball valves adopt a side-mounted structure. When the internal seals wear out or malfunction and require maintenance, the valve body must be completely disassembled from the pipeline system. For valves in large-diameter, high-pressure conditions, the disassembly and assembly process is not only labor-intensive and time-consuming, but also leads to prolonged production line downtime, seriously affecting production efficiency. Secondly, traditional valve seat sealing structures mostly use ordinary cylindrical springs to provide preload. The spring preload is unevenly distributed, and after long-term operation, it is prone to spring fatigue and failure, resulting in a decrease in sealing pressure and subsequent media leakage. Furthermore, a single preload structure cannot adapt to large fluctuations in media pressure, especially under high pressure. The valve has several drawbacks: poor sealing reliability under operating conditions; poor sealing reliability ...

[0004] Therefore, developing a top-mounted C-type wear-resistant ball valve that is easy to maintain, has reliable sealing, excellent wear resistance, and stable operation has become an urgent technical problem to be solved in this field. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, one of the objectives of the present invention is to provide a top-mounted C-type wear-resistant ball valve.

[0006] One of the objectives of this invention is achieved through the following technical solution: A C-type wear-resistant ball valve includes a valve body, a valve cover, a C-shaped ball, a valve stem, a left valve seat assembly, a right valve seat assembly, a stuffing box assembly, and a drive connection bracket. The valve body is an integral cast structure with flange connection ends at both ends, forming a spherical valve cavity inside. The valve cover is fixedly connected to the top opening of the valve body by multiple sets of bolt and nut assemblies. The C-shaped ball is rotatably disposed within the spherical valve cavity, and a connecting groove for mating with the lower end of the valve stem is opened on the upper part of the C-shaped ball. The left and right valve seat assemblies are symmetrically disposed on the left and right sides of the C-shaped ball, respectively, and both form a sealing fit with the outer spherical surface of the C-shaped ball. The valve stem passes through the drive connection bracket, the stuffing box assembly, and the valve cover sequentially from top to bottom, and its lower end is inserted into the connecting groove of the C-shaped ball to form a transmission connection. The stuffing box assembly is disposed in the center hole at the top of the valve cover to achieve a dynamic seal between the valve stem and the valve cover. The drive connection bracket is fixedly installed on the top of the valve cover for connecting an external drive device.

[0007] As a further improvement to the above technical solution: The C-shaped sphere is a C-shaped structure with an opening on one side, and its opening direction is consistent with the direction of the fluid channel. The outer spherical surface of the C-shaped sphere is coated with a hard alloy wear-resistant layer, and the thickness of the hard alloy wear-resistant layer is 0.5-2mm.

[0008] The left and right valve seat assemblies have the same structure, both including a valve seat body, a sealing ring, a disc spring, and a retaining ring. The inner end face of the valve seat body is provided with a sealing surface that mates with the outer spherical surface of the C-shaped ball. The sealing ring is embedded in the annular groove between the valve seat body and the valve body. The disc spring is sleeved on the outer side of the valve seat body, with one end abutting against the stepped surface of the valve body and the other end abutting against the outer end face of the valve seat body through the retaining ring.

[0009] A cobalt-based hard alloy layer is welded onto the sealing surface of the valve seat body, and the cobalt-based hard alloy layer and the hard alloy wear-resistant layer on the outer spherical surface of the C-shaped ball form a wear-resistant sealing pair.

[0010] The stuffing box assembly includes a stuffing gland, a stuffing sleeve, and multi-layer packing; the multi-layer packing fills the stuffing box cavity at the top of the valve cover, the stuffing sleeve is positioned above the multi-layer packing, and the stuffing gland is fixed to the top of the valve cover by bolts, pressing down on the stuffing sleeve and multi-layer packing.

[0011] The multilayer packing adopts a structure of alternating stacking of graphite packing and polytetrafluoroethylene packing, with graphite packing provided in both the top and bottom layers.

[0012] The lower end of the valve stem is provided with an anti-rotation flat head, and the connecting groove on the upper part of the C-shaped ball is a flat groove structure that matches the anti-rotation flat head. The valve stem and the C-shaped ball achieve circumferential fixed transmission through the anti-rotation flat head and the flat groove.

[0013] A thrust bearing is also fitted on the valve stem. The thrust bearing is located between the top stepped surface of the valve cover and the packing sleeve and is used to bear the axial load of the valve stem.

[0014] The drive connection bracket is a box-shaped structure. Its bottom is fixedly connected to the top of the valve cover by bolts. Its top is provided with a flange for installing the actuator. The side wall of the drive connection bracket has an inspection window.

[0015] The bottom of the valve body is provided with a drain port, and a removable drain plug is installed on the drain port for periodically draining the sediment in the valve cavity.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The valve adopts an integral cast valve body with a top valve cover, which is an upper-mounted structure. When the valve is under maintenance, there is no need to disassemble the valve body from the pipeline. Only the connecting bolts of the top valve cover need to be removed. All internal components such as the valve cover, ball, valve seat assembly, and valve stem can be taken out from the top of the valve body for inspection, repair or replacement. This greatly reduces the difficulty and workload of maintenance, significantly shortens the production line downtime, and reduces production and maintenance costs.

[0017] 2. The valve employs a symmetrically arranged dual-seat assembly, using disc springs to provide continuous and uniform pre-tightening force to the valve seats, ensuring the initial sealing performance of the valve under low-pressure conditions. Simultaneously, it utilizes the medium pressure to create a self-tightening sealing effect; the sealing specific pressure automatically increases with rising medium pressure, adapting to different pressure levels and ensuring reliable sealing under high-pressure conditions. The dual-seat structure also enables bidirectional sealing, expanding the valve's applicability.

[0018] 3. The outer surface of the valve body is coated with a hard alloy wear-resistant layer, and the valve seat sealing surface is overlaid with cobalt-based hard alloy. Together, they form a high-hardness, high-wear-resistant metal-to-metal wear-resistant sealing pair. This sealing pair effectively resists the scouring, scraping, and abrasion of solid particles in the medium, significantly reducing the wear rate of the sealing surface. It avoids the problems of easy wear and failure of traditional valve sealing surfaces, extending the valve's service life by 3-5 times under abrasive media conditions.

[0019] 4. The stuffing box adopts a combined structure of alternating stacked graphite packing and polytetrafluoroethylene (PTFE) packing, with graphite packing placed at both the top and bottom layers. Graphite packing possesses excellent high-temperature resistance, self-lubrication, and sealing properties, while PTFE packing exhibits good chemical corrosion resistance and a low coefficient of friction. The complementary advantages of both materials give the stuffing box the characteristics of high-temperature resistance, corrosion resistance, wear resistance, and low friction, effectively preventing external leakage at the valve stem and improving the safety and stability of valve operation.

[0020] 5. A thrust bearing is installed between the valve stem and the valve cover, which can withstand all the axial load generated during the opening and closing of the valve stem. It converts the sliding friction between the valve stem and the valve cover into rolling friction, which significantly reduces the opening and closing friction resistance, reduces the output torque of the drive device, and effectively limits the axial movement of the valve stem. It also ensures the coaxiality of the ball rotation and the uniformity of the sealing surface contact, making the valve opening and closing more flexible and stable.

[0021] 6. A drain port connected to the lowest point of the valve cavity is provided at the bottom of the valve body, and a removable drain plug is provided. This allows for the regular and thorough removal of solid particles and impurities deposited in the valve cavity, preventing malfunctions such as ball jamming and abnormal wear of the sealing surface caused by deposit accumulation. This effectively ensures the long-term stable operation of the valve in media containing solid particles.

[0022] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0023] Figure 1 This is the front view of this embodiment; Figure 2 This is a schematic diagram of the C-shaped sphere in this embodiment.

[0024] In the diagram: 1. Valve body; 12. Drain outlet; 13. Drain plug; 2. Valve cover; 3. C-shaped ball; 4. Valve stem. Detailed Implementation

[0025] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0026] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0028] like Figure 1-2As shown, the C-type wear-resistant ball valve of this embodiment includes a valve body 1, a valve cover 2, a C-type ball 3, a valve stem 4, a left valve seat assembly, a right valve seat assembly, a stuffing box assembly, and a drive connection bracket. The valve body 1 is an integral cast structure with flange connection ends at both ends, and a spherical valve cavity is formed inside the valve body 1. The valve cover 2 is fixedly connected to the top opening of the valve body 1 by multiple sets of bolt and nut assemblies. The C-type ball 3 is rotatably disposed in the spherical valve cavity, and a connecting groove that mates with the lower end of the valve stem 4 is opened on the upper part of the C-type ball 3. The left valve seat assembly and the right valve seat assembly are symmetrically disposed on the left and right sides of the C-type ball 3, and both form a sealing fit with the outer spherical surface of the C-type ball 3. The valve stem 4 passes through the drive connection bracket, the stuffing box assembly, and the drive connection bracket from top to bottom. The valve cover 2 has its lower end inserted into the connecting groove of the C-shaped ball 3 to form a transmission connection. The stuffing box assembly is set in the center hole at the top of the valve cover 2 to achieve dynamic sealing between the valve stem 4 and the valve cover 2. The drive connection bracket is fixedly installed on the top of the valve cover 2 to connect an external drive device. The C-shaped ball 3 is a C-shaped structure with one side opening, and its opening direction is consistent with the direction of the fluid channel. The outer spherical surface of the C-shaped ball 3 is coated with a hard alloy wear-resistant layer with a thickness of 0.5-2mm. The left valve seat assembly and the right valve seat assembly have the same structure, both including a valve seat body, a sealing ring, a disc spring, and a retaining ring. The inner end face of the valve seat body is provided with a sealing surface that mates with the outer spherical surface of the C-shaped ball 3. The sealing ring is embedded in the valve seat body and the outer spherical surface of the C-shaped ball 3. Inside the annular groove between valve bodies 1, a disc spring is sleeved on the outside of the valve seat body. One end of the disc spring abuts against the stepped surface of valve body 1, and the other end abuts against the outer end face of the valve seat body through a retaining ring. A cobalt-based hard alloy layer is welded onto the sealing surface of the valve seat body. The cobalt-based hard alloy layer and the hard alloy wear-resistant layer on the outer spherical surface of the C-shaped ball 3 form a wear-resistant sealing pair. The stuffing box assembly includes a stuffing gland, a stuffing sleeve, and multi-layer packing. The multi-layer packing fills the stuffing box cavity at the top of the valve cover 2. The stuffing sleeve is positioned above the multi-layer packing. The stuffing gland is fixed to the top of the valve cover 2 by bolts and presses down on the stuffing sleeve and multi-layer packing. The multi-layer packing adopts a structure of alternating stacking of graphite packing and polytetrafluoroethylene packing, and is provided in both the uppermost and lowermost layers. The valve stem 4 is fitted with graphite packing. The lower end of the valve stem 4 is equipped with an anti-rotation flat head. The connecting groove on the upper part of the C-shaped ball 3 is a flat groove structure that matches the anti-rotation flat head. The valve stem 4 and the C-shaped ball 3 achieve circumferential fixed transmission through the anti-rotation flat head and the flat groove. A thrust bearing is also fitted on the valve stem 4. The thrust bearing is located between the top step surface of the valve cover 2 and the packing sleeve to bear the axial load of the valve stem 4. The drive connection bracket is a box-type structure. Its bottom is fixedly connected to the top of the valve cover 2 by bolts. Its top is equipped with a flange for installing the actuator. The side wall of the drive connection bracket is provided with an inspection window. The bottom of the valve body 1 is provided with a drain port 12. A removable drain plug 13 is installed on the drain port 12 for periodically draining the sediment in the valve cavity.

[0029] Working principle: The external drive unit is fixedly installed on the flange at the top of the drive connection bracket, and its output shaft forms a transmission connection with the upper end of the valve stem 4. When the drive unit outputs rotational torque, it drives the valve stem 4 to rotate synchronously. The anti-rotation flat head at the lower end of the valve stem 4 is embedded in the matching flat groove on the upper part of the C-shaped ball 3, transmitting the rotational torque to the C-shaped ball 3 without gap, so that the C-shaped ball 3 rotates within a 90° range around the axis of the valve stem 4 in the spherical valve cavity inside the valve body 1. When the opening on one side of the C-shaped ball 3 is fully aligned with the fluid passages at both ends of the valve body 1, the valve is in the fully open state. Fluid flows in from the flange connection end at one end of the valve body 1, passes through the C-shaped flow passage of the C-shaped ball 3, and flows out from the flange connection end at the other end. At this time, the fluid flow resistance is minimal. When the drive device rotates the valve stem 4 and the C-shaped ball 3 by 90°, so that the opening direction of the C-shaped ball 3 is perpendicular to the fluid passage direction of the valve body 1, the solid spherical surface of the C-shaped ball 3 blocks the fluid passage of the valve body 1, and the valve switches to the fully closed state, blocking the fluid flow.

[0030] The valve's bidirectional sealing function is achieved by symmetrically arranged left and right valve seat assemblies. The sealing surface of the inner end face of the valve seat body fits against the outer spherical surface of the C-shaped ball 3 to form the main sealing surface. A disc spring is sleeved on the outside of the valve seat body, with one end abutting against the stepped surface of the valve body 1 and the other end abutting against the outer end face of the valve seat body through a retaining ring. It continuously applies a pre-tightening force to the valve seat body, pushing it to always press against the outer spherical surface of the C-shaped ball 3, achieving the initial low-pressure seal of the valve. When the valve is closed and the medium pressure increases, the medium pressure acts on the outer end face of the valve seat body, forming a medium self-tightening force, further pushing the valve seat body to press against the C-shaped ball 3. The sealing specific pressure increases with the increase of the medium pressure, ensuring the sealing reliability under high-pressure conditions. The sealing ring is embedded in the annular groove between the valve seat body and the valve body 1, achieving a static seal between the valve seat body and the valve body 1, preventing fluid leakage from the mating gap between the two.

[0031] For operating conditions involving abrasive media containing solid particles and dust, the outer spherical surface of the C-type ball 3 is coated with a 0.5-2mm thick hard alloy wear-resistant layer, while the sealing surface of the valve seat body is overlaid with a cobalt-based hard alloy layer. Together, they form a high-hardness, high-wear-resistant metal-to-metal wear-resistant sealing pair. During valve opening and closing, the relative friction between the C-type ball 3 and the valve seat body occurs only on the surface of the hard alloy layer, effectively resisting the scouring, scraping, and abrasion of solid particles in the medium, significantly reducing the wear rate of the sealing surface, and extending the overall service life of the valve.

[0032] The dynamic seal between the valve stem 4 and the valve cover 2 is achieved by a stuffing box assembly. Multiple layers of packing fill the stuffing box cavity at the top of the valve cover 2, employing an alternating stacked structure of graphite packing and PTFE packing, with graphite packing at both the top and bottom layers. The packing gland is bolted to the top of the valve cover 2, pressing down on the packing gland. The packing gland evenly transmits the clamping force to the multiple layers of packing, causing the packing to undergo radial elastic deformation and tightly adhere to the outer surface of the valve stem 4 and the inner wall of the stuffing box cavity of the valve cover 2, blocking the leakage path of fluid along the axial direction of the valve stem 4. The graphite packing possesses excellent high-temperature resistance and self-lubricating properties, while the PTFE packing exhibits good chemical corrosion resistance and a low coefficient of friction. The alternating combination of these two materials balances sealing performance, wear resistance, and temperature adaptability.

[0033] The thrust bearing fitted on the valve stem 4 is located between the top stepped surface of the valve cover 2 and the packing gland. It bears all the axial load generated by the valve stem 4 during opening and closing, converting the sliding friction between the valve stem 4 and the valve cover 2 into rolling friction. This significantly reduces frictional resistance and the output torque of the drive unit, while effectively limiting the axial movement of the valve stem 4, ensuring the coaxiality of the C-shaped ball 3 and the uniformity of the sealing surface contact. The drive connection bracket adopts a box-type structure, providing stable installation support for the external drive unit. The inspection window on its side wall allows for daily inspection and maintenance of the connection between the valve stem 4 and the drive unit, as well as the packing gland assembly, without disassembling the drive unit.

[0034] A drain port 12 located at the bottom of the valve body 1 connects to the lowest point of the spherical valve cavity, and a removable drain plug 13 is installed on the drain port 12. During long-term operation of the valve, solid particles and impurities in the medium will gradually accumulate at the bottom of the valve cavity. Regularly disassembling the drain plug 13 allows the deposits in the valve cavity to be completely discharged through the drain port 12, preventing the accumulation of deposits from causing malfunctions such as jamming of the C-shaped ball 3 and abnormal wear of the sealing surface, thus ensuring the long-term stable operation of the valve.

[0035] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A C-type wear-resistant ball valve with an upper mounting, characterized in that, The valve body (1) includes a valve cover (2), a C-shaped ball (3), a valve stem (4), a left valve seat assembly, a right valve seat assembly, a stuffing box assembly, and a drive connection bracket. The valve body (1) is an integral cast structure with flange connection ends at both ends, and a spherical valve cavity is formed inside the valve body (1). The valve cover (2) is fixedly connected to the top opening of the valve body (1) by multiple sets of bolt and nut assemblies. The C-shaped ball (3) is rotatably set in the spherical valve cavity, and a connecting groove that mates with the lower end of the valve stem (4) is opened on the upper part of the C-shaped ball (3). The left valve seat assembly... The valve stem (4) and the right valve seat assembly are symmetrically arranged on the left and right sides of the C-shaped ball (3), and both form a sealing fit with the outer spherical surface of the C-shaped ball (3); the valve stem (4) passes through the drive connection bracket, the stuffing box assembly and the valve cover (2) from top to bottom, and its lower end is inserted into the connecting groove of the C-shaped ball (3) to form a transmission connection; the stuffing box assembly is set in the top center hole of the valve cover (2) to realize the dynamic seal between the valve stem (4) and the valve cover (2); the drive connection bracket is fixedly installed on the top of the valve cover (2) to connect the external drive device.

2. The C-type wear-resistant ball valve according to claim 1, characterized in that, The C-shaped sphere (3) is a C-shaped structure with a single-sided opening. Its opening direction is consistent with the direction of the fluid channel. The outer spherical surface of the C-shaped sphere (3) is coated with a hard alloy wear-resistant layer, and the thickness of the hard alloy wear-resistant layer is 0.5-2mm.

3. The C-type wear-resistant ball valve according to claim 1, characterized in that, The left and right valve seat assemblies have the same structure, both including a valve seat body, a sealing ring, a disc spring, and a retaining ring. The inner end face of the valve seat body is provided with a sealing surface that mates with the outer spherical surface of the C-shaped ball (3). The sealing ring is embedded in the annular groove between the valve seat body and the valve body (1). The disc spring is sleeved on the outer side of the valve seat body, with one end abutting against the stepped surface of the valve body (1) and the other end abutting against the outer end face of the valve seat body through the retaining ring.

4. The C-type wear-resistant ball valve according to claim 3, characterized in that, A cobalt-based hard alloy layer is welded onto the sealing surface of the valve seat body, and the cobalt-based hard alloy layer and the hard alloy wear-resistant layer on the outer spherical surface of the C-shaped ball (3) form a wear-resistant sealing pair.

5. The C-type wear-resistant ball valve according to claim 1, characterized in that, The stuffing box assembly includes a stuffing gland, a stuffing sleeve, and multi-layer packing; the multi-layer packing fills the stuffing box cavity at the top of the valve cover (2), the stuffing sleeve is positioned above the multi-layer packing, and the stuffing gland is fixed to the top of the valve cover (2) by bolts and presses down the stuffing sleeve and multi-layer packing.

6. The C-type wear-resistant ball valve according to claim 5, characterized in that, The multilayer packing adopts a structure of alternating stacking of graphite packing and polytetrafluoroethylene packing, with graphite packing provided in both the top and bottom layers.

7. The C-type wear-resistant ball valve according to claim 1, characterized in that, The lower end of the valve stem (4) is provided with an anti-rotation flat head, and the connecting groove on the upper part of the C-shaped ball (3) is a flat groove structure that matches the anti-rotation flat head. The valve stem (4) and the C-shaped ball (3) achieve circumferential fixed transmission through the anti-rotation flat head and the flat groove.

8. The C-type wear-resistant ball valve according to claim 1, characterized in that, A thrust bearing is also fitted on the valve stem (4). The thrust bearing is located between the top step surface of the valve cover (2) and the packing sleeve and is used to bear the axial load of the valve stem (4).

9. The C-type wear-resistant ball valve according to claim 1, characterized in that, The drive connection bracket is a box-shaped structure. Its bottom is fixedly connected to the top of the valve cover (2) by bolts. Its top is provided with a flange for installing the actuator. The side wall of the drive connection bracket is provided with an inspection window.

10. The C-type wear-resistant ball valve according to claim 1, characterized in that, The bottom of the valve body (1) is provided with a drain port (12), and a detachable drain plug (13) is installed on the drain port (12) for periodically draining the sediment in the valve cavity.

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