Six eccentric all-metal hard-seated butterfly valve

Abstract

The application discloses a six-eccentric full-metal hard-against-hard butterfly valve, which comprises a hand wheel, a worm gear transmission mechanism, a valve rod, a valve body, a valve plate and a metal valve seat; the hand wheel is fixedly connected with an input shaft of the worm gear transmission mechanism through a hand wheel support; the worm gear transmission mechanism is fixedly installed at the upper end of the valve body through box body fixing bolts; the upper end of the valve rod is fixedly connected with an output end of the worm gear transmission mechanism; the valve body adopts an integral casting structure, is compact in structure, good in rigidity, high in strength, can bear higher working pressure and impact load, avoids the connection leakage problem of split valve bodies, adopts standard flange connection structures at both ends of the valve body, is simple and reliable in connection with industrial pipelines, and is convenient and fast in installation and dismounting, so that the valve is convenient for daily maintenance and overhaul; meanwhile, the valve parts are high in universality, the machining and manufacturing process is mature, the production cost is low, and the valve is suitable for large-scale industrial production and popularization and application.

Description

Technical Field

[0001] This invention relates to the field of butterfly valve technology, and in particular to a six-eccentric all-metal hard-on-hard butterfly valve. Background Technology

[0002] Butterfly valves, as one of the most widely used valve types in pipeline fluid control systems, are extensively used in many industrial fields such as petroleum, chemical, power, metallurgy, municipal water supply and drainage, and gas transmission due to their significant advantages such as compact structure, small size, light weight, rapid opening and closing, and low flow resistance. They primarily function to cut off and connect the medium within pipelines and regulate flow. With the continuous development of industrial technology, extreme conditions such as high temperature, high pressure, strong corrosion, and high wear place increasingly stringent requirements on the sealing performance, service life, and operational reliability of butterfly valves. All-metal hard-to-hard-seal butterfly valves, due to their ability to adapt to these harsh conditions, have gradually become a focus of industry research and application.

[0003] Most of the mainstream metal-sealed butterfly valves on the market currently adopt single eccentric, double eccentric, or triple eccentric structural designs.

[0004] Among them, the triple eccentric butterfly valve improves the problem of severe friction and wear on the sealing surface of the traditional butterfly valve to a certain extent by introducing three eccentric parameters, thus extending the service life of the valve. However, it still has many insurmountable defects in actual engineering applications.

[0005] First, the motion trajectory optimization of the triple eccentric structure is limited. During the opening and closing process, there is still local friction and scraping between the valve plate sealing surface and the valve seat sealing surface. Especially under the condition of frequent opening and closing, the sealing surface is prone to wear, scratches and peeling, which leads to a rapid decline in sealing performance and eventually causes media leakage.

[0006] Secondly, the sealing pressure distribution of triple eccentric butterfly valves is uneven, which can easily lead to local sealing failure under high pressure differential conditions, making it impossible to achieve true zero leakage and failing to meet the requirements of high-precision sealing.

[0007] Furthermore, under high-temperature conditions, metal materials undergo thermal expansion and deformation. The structure of traditional triple-eccentric butterfly valves cannot effectively compensate for this deformation, easily leading to sealing surface jamming and inability to open or close, or excessive sealing gaps resulting in a loss of sealing effect. Simultaneously, the stem sealing structure of most existing butterfly valves is relatively simple, easily leading to axial leakage of the medium along the valve stem after prolonged use. This not only wastes the medium but may also pose a threat to the surrounding environment and the safety of operators. Some butterfly valves also suffer from insufficient stability in their transmission mechanisms, making them prone to transmission jamming and failure under high torque conditions, affecting the normal operation of the valve and the stable operation of the system. Summary of the Invention

[0008] In order to overcome the shortcomings of the prior art, one of the objectives of this invention is to provide a six-eccentric all-metal hard-on-hard butterfly valve.

[0009] One of the objectives of this invention is achieved through the following technical solution: A six-eccentric all-metal hard-on-hard butterfly valve includes a handwheel, a worm gear transmission mechanism, a valve stem, a valve body, a valve plate, and a metal valve seat. The handwheel is fixedly connected to the input shaft of the worm gear transmission mechanism via a handwheel bracket. The worm gear transmission mechanism is fixedly mounted on the upper end of the valve body via housing fixing bolts. The upper end of the valve stem is fixedly connected to the output end of the worm gear transmission mechanism, and the lower end of the valve stem extends into the valve body and is fixedly connected to the valve plate. The metal valve seat is fixedly mounted on the valve body via a valve seat pressure plate and valve seat fixing bolts. On the inner wall of the body's channel; the sealing surface of the valve plate and the sealing surface of the metal valve seat form a full metal hard-on-hard sealing pair; the butterfly valve adopts a six-eccentric structure design, including the first eccentricity between the valve stem axis and the valve body channel axis, the second eccentricity between the valve plate sealing surface axis and the valve body channel axis, the third eccentricity between the valve seat sealing surface axis and the valve body channel axis, the fourth eccentricity between the valve plate sealing surface cone angle and the valve seat sealing surface cone angle, the fifth eccentricity between the valve stem axis and the valve plate sealing surface axis, and the sixth eccentricity between the valve seat sealing surface axis and the valve body channel axis.

[0010] The worm gear transmission mechanism includes a worm gear box, a box cover, a worm gear, and a worm; one end of the worm is fixedly connected to the input shaft, and the worm gear meshes with the worm wheel for transmission; the worm wheel is fixedly mounted on the upper end of the valve stem; the box cover is fixedly installed on the top of the worm gear box by box cover fixing bolts.

[0011] Furthermore, an upper bearing is provided between the valve stem and the worm gear box, and a lower bearing is provided between the valve stem and the valve body; the upper bearing and the lower bearing respectively support the upper and lower parts of the valve stem.

[0012] Furthermore, an upper valve stem sealing assembly is provided between the valve stem and the worm gear box, and a lower valve stem sealing assembly is provided between the valve stem and the valve body; the upper valve stem sealing assembly is located below the upper bearing, and the lower valve stem sealing assembly is located above the lower bearing.

[0013] Furthermore, the valve plate is fixedly installed at the lower end of the valve stem by a valve plate pressure plate and valve plate fixing bolts; the sealing surface of the valve plate is a hardened metal conical surface.

[0014] Furthermore, the sealing surface of the metal valve seat is a hardened metal conical surface; a sealing gasket is provided between the metal valve seat and the valve body.

[0015] Furthermore, the top of the worm gear box is also provided with an opening indicator mechanism; the opening indicator mechanism includes an opening indicator plate and an indicator pointer; the indicator pointer is fixedly installed on the top of the valve stem, and the opening indicator plate is fixedly installed on the box cover.

[0016] Furthermore, a lower valve stem bearing seat is provided at the lower end of the valve body; a bearing supporting the lower end of the valve stem is installed inside the lower valve stem bearing seat; and a lower valve stem end cap is fixedly installed at the bottom of the lower valve stem bearing seat by end cap fixing bolts.

[0017] Furthermore, the valve body adopts an integral casting structure; both ends of the valve body are provided with flange connection structures, and multiple bolt holes are evenly distributed on the flanges.

[0018] Furthermore, the center of the valve plate is eccentrically positioned relative to the axis of the valve stem; during the opening process, the sealing surface of the valve plate completely separates from the sealing surface of the metal valve seat at the instant of opening, without any frictional contact.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention employs a six-eccentric structure design. Through the synergistic optimization of six eccentric parameters, the movement trajectory of the valve plate sealing surface is precisely controlled, ensuring that the valve plate completely disengages from the valve seat sealing surface at the initial moment of opening. Throughout the entire opening and closing process, there is no frictional contact between the two, fundamentally eliminating the source of wear and scratches on the sealing surface. Simultaneously, both the valve plate and valve seat sealing surfaces undergo hardening treatment, possessing extremely high hardness and wear resistance. This effectively resists the erosion of solid particles in the medium and the corrosion of corrosive media, significantly extending the valve's service life under high-wear and highly corrosive conditions.

[0020] 2. The six-eccentric structure ensures that the sealing surface precisely fits along a preset trajectory when the valve plate is closed, forming a uniform surface contact seal. This results in a more reasonable and uniform distribution of sealing pressure, guaranteeing consistent sealing pressure throughout the sealing pair even under high pressure differential and large-diameter conditions, effectively preventing localized seal failure. The all-metal hard-on-hard sealing pair can withstand higher operating temperatures and pressures. Combined with the sealing gasket between the valve seat and valve body, it achieves reliable dual sealing both internally and externally, meeting the stringent zero-leakage requirements of industrial production.

[0021] 3. The unique design of the six-eccentric structure can adapt to the thermal expansion and contraction deformation of metal materials under high-temperature conditions, avoiding the problems of sealing surface jamming or excessive sealing gap caused by temperature changes. This ensures the normal opening and closing and stable sealing of the valve within a wide temperature range, and greatly improves the adaptability and reliability of the valve under extreme conditions such as high-temperature steam and high-temperature flue gas.

[0022] 4. This invention features two independent valve stem sealing assemblies, forming a double sealing barrier that effectively prevents media from leaking upwards along the valve stem axis. The sealing assemblies utilize mature and reliable sealing structures and materials, exhibiting excellent sealing performance and service life. Even under long-term operation or pressure fluctuations, they maintain a stable sealing effect, completely eliminating the safety hazard of external valve stem leakage.

[0023] 5. The worm gear transmission mechanism provides significant speed reduction and torque enhancement, delivering sufficient opening and closing torque with minimal operating force, thus reducing operator workload. The transmission mechanism operates smoothly with low noise and high efficiency, ensuring stable and precise valve plate rotation. An opening indicator at the top of the transmission mechanism clearly and accurately displays the valve's opening angle and corresponding flow status, facilitating real-time monitoring of the valve's operating condition and enabling precise flow regulation.

[0024] 6. The valve body adopts an integral casting structure, which is compact, rigid, and strong, and can withstand high working pressure and impact loads. It avoids the connection leakage problems that are prone to occur in split valve bodies. The valve body adopts a standard flange connection structure at both ends, which makes the connection with industrial pipelines simple and reliable, and facilitates quick and easy installation and disassembly. It is convenient for daily maintenance and repair of the valve. At the same time, the valve parts have strong versatility, mature processing and manufacturing technology, and low production cost, making it suitable for large-scale industrial production and widespread application.

[0025] 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

[0026] Figure 1 This is a schematic diagram of the structure of this embodiment; Figure 2 This is a schematic diagram of the handwheel bracket in this embodiment; Figure 3 This is a schematic diagram of the worm gear box in this embodiment.

[0027] In the diagram: 1. Handwheel; 10. Valve stem; 2. Handwheel bracket; 3. Input shaft; 4. Worm gearbox; 5. Box cover. Detailed Implementation

[0028] 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.

[0029] 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.

[0030] 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.

[0031] like Figure 1-3As shown, the six-eccentric all-metal hard-on-hard butterfly valve of this embodiment includes a handwheel 1, a worm gear transmission mechanism, a valve stem 10, a valve body, a valve plate, and a metal valve seat. The handwheel 1 is fixedly connected to the input shaft 3 of the worm gear transmission mechanism via a handwheel bracket 2. The worm gear transmission mechanism is fixedly installed on the upper end of the valve body via housing fixing bolts. The upper end of the valve stem 10 is fixedly connected to the output end of the worm gear transmission mechanism, and the lower end of the valve stem 10 extends into the valve body and is fixedly connected to the valve plate. The metal valve seat is fixedly installed on the inner wall of the valve body via a valve seat pressure plate and valve seat fixing bolts. The sealing surface of the valve plate and the sealing surface of the metal valve seat form an all-metal hard-on-hard sealing pair. The butterfly valve adopts a six-eccentric structure. The design includes a first eccentricity between the valve stem axis and the valve body passage axis, a second eccentricity between the valve plate sealing surface axis and the valve body passage axis, a third eccentricity between the valve seat sealing surface axis and the valve body passage axis, a fourth eccentricity between the valve plate sealing surface cone angle and the valve seat sealing surface cone angle, a fifth eccentricity between the valve stem axis and the valve plate sealing surface axis, and a sixth eccentricity between the valve seat sealing surface axis and the valve body passage axis. The worm gear transmission mechanism includes a worm gear box 4, a box cover 5, a worm gear, and a worm. One end of the worm is fixedly connected to the input shaft 3, and the worm gear meshes with the worm wheel for transmission. The worm wheel is fixedly mounted on the upper end of the valve stem 10. The box cover 5 is fixedly installed on the top of the worm gear box 4 by box cover fixing bolts. The valve stem 10 and the worm gear... An upper bearing is installed between the worm gear box 4 and the valve stem 10, and a lower bearing is installed between the valve stem 10 and the valve body. The upper and lower bearings support the upper and lower parts of the valve stem 10, respectively. An upper valve stem sealing assembly is installed between the valve stem 10 and the worm gear box 4, and a lower valve stem sealing assembly is installed between the valve stem 10 and the valve body. The upper valve stem sealing assembly is located below the upper bearing, and the lower valve stem sealing assembly is located above the lower bearing. The valve plate is fixedly installed at the lower end of the valve stem 10 by a valve plate pressure plate and valve plate fixing bolts. The sealing surface of the valve plate is a hardened metal conical surface, and the sealing surface of the metal valve seat is a hardened metal conical surface. A sealing gasket is installed between the metal valve seat and the valve body. The top of the worm gear box 4... It is also equipped with an opening degree indicator mechanism; the opening degree indicator mechanism includes an opening degree indicator plate and an indicator pointer; the indicator pointer is fixedly installed on the top of the valve stem 10, the opening degree indicator plate is fixedly installed on the box cover 5, and a lower valve stem bearing seat is provided at the lower end of the valve body; a bearing supporting the lower end of the valve stem 10 is installed in the lower valve stem bearing seat; the bottom of the lower valve stem bearing seat is fixedly installed with the lower valve stem end cover by end cover fixing bolts, and the valve body adopts an integral casting structure; flange connection structures are provided at both ends of the valve body, and multiple bolt holes are evenly distributed on the flanges; the center of the valve plate is eccentrically set with respect to the axis of the valve stem 10; during the opening process, the sealing surface of the valve plate is completely separated from the sealing surface of the metal valve seat at the moment of opening, without frictional contact.

[0032] Working principle: When the operator turns handwheel 1, handwheel 1 is stably supported by handwheel bracket 2 and drives input shaft 3 to rotate synchronously. Input shaft 3 transmits rotational power to the worm inside worm gear box 4. The worm meshes with the worm wheel, converting the input high-speed, low-torque rotational motion into low-speed, high-torque rotational motion, which is then transmitted to the worm wheel fixedly mounted on the upper end of valve stem 10, thereby driving valve stem 10 to rotate smoothly around its own axis. The upper part of valve stem 10 is supported by an upper bearing installed in worm gear box 4, and the lower part is jointly supported by a lower bearing installed in the valve body and lower valve stem bearing seat. The upper and lower bearings together constrain the radial and axial movement of valve stem 10, ensuring coaxiality and transmission accuracy during the rotation of valve stem 10. The cover 5 is sealed on the top of worm gear box 4 by cover fixing bolts, isolating external dust, moisture and impurities from entering the transmission mechanism and preventing corrosion and jamming of transmission components.

[0033] The lower end of the valve stem 10 is rigidly connected to the valve plate through the valve plate pressure plate and the valve plate fixing bolts. When the valve stem 10 rotates, it synchronously drives the valve plate to rotate within a 90° range in the valve body channel. Because the butterfly valve adopts a six-eccentric structure design, including the first eccentricity between the valve stem axis and the valve body passage axis, the second eccentricity between the valve plate sealing surface axis and the valve body passage axis, the third eccentricity between the valve seat sealing surface axis and the valve body passage axis, the fourth eccentricity between the valve plate sealing surface cone angle and the valve seat sealing surface cone angle, the fifth eccentricity between the valve stem axis and the valve plate sealing surface axis, and the sixth eccentricity between the valve seat sealing surface axis and the valve body passage axis, and the center of the valve plate is further eccentrically set to the axis of the valve stem 10, so that at the initial moment of opening, the hardened metal conical sealing surface of the valve plate is completely separated from the hardened metal conical sealing surface of the metal valve seat, and there is no frictional contact between the two during the entire opening process; during the closing process, the valve plate sealing surface gradually approaches the metal valve seat sealing surface along the preset eccentric trajectory, and finally precisely presses together at the closed position to form a surface contact all-metal hard-to-hard sealing pair, realizing reliable cutoff of the medium in the valve body passage. The metal valve seat is fastened to the inner wall of the valve body by a valve seat pressure plate and valve seat fixing bolts. The sealing gasket between the metal valve seat and the valve body can fill the mating gap between the two to prevent the medium from leaking out from the valve seat mounting surface.

[0034] A pointer is fixedly installed at the top of the valve stem 10, and a corresponding opening indicator is fixedly installed on the cover 5. The pointer rotates synchronously with the valve stem 10, and its direction on the opening indicator can intuitively and accurately display the valve's opening angle and corresponding flow status, facilitating real-time monitoring of the valve's operating condition by operators. The upper valve stem sealing assembly between the valve stem 10 and the worm gear box 4 is located below the upper bearing, while the lower valve stem sealing assembly between the valve stem 10 and the valve body is located above the lower bearing. These two valve stem sealing assemblies form a double sealing barrier, effectively preventing the medium from leaking upwards along the valve stem 10 to the transmission mechanism and the external environment. A lower valve stem end cap is installed at the bottom of the lower valve stem bearing seat at the lower end of the valve body via end cap fixing bolts. This seals the bottom opening of the lower valve stem bearing seat, protecting the internal support bearing from media erosion and corrosion, and extending the bearing's service life. The valve body adopts an integral casting structure, and the flange connection structure at both ends can achieve a rigid connection with the industrial pipeline system via flange bolts, ensuring the valve's installation stability and operational reliability under harsh conditions such as high pressure and high temperature.

[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 six-eccentric all-metal hard-on-hard butterfly valve, characterized in that, The valve body includes a handwheel (1), a worm gear transmission mechanism, a valve stem (10), a valve body, a valve plate, and a metal valve seat. The handwheel (1) is fixedly connected to the input shaft (3) of the worm gear transmission mechanism via a handwheel bracket (2). The worm gear transmission mechanism is fixedly installed on the upper end of the valve body via housing fixing bolts. The upper end of the valve stem (10) is fixedly connected to the output end of the worm gear transmission mechanism, and the lower end of the valve stem (10) extends into the valve body and is fixedly connected to the valve plate. The metal valve seat is fixedly installed via a valve seat pressure plate and valve seat fixing bolts. It is fixedly installed on the inner wall of the valve body channel; the sealing surface of the valve plate and the sealing surface of the metal valve seat form a full metal hard-to-hard sealing pair; the butterfly valve adopts a six-eccentric structure design, including the first eccentricity between the valve stem axis and the valve body channel axis, the second eccentricity between the valve plate sealing surface axis and the valve body channel axis, the third eccentricity between the valve seat sealing surface axis and the valve body channel axis, the fourth eccentricity between the valve plate sealing surface cone angle and the valve seat sealing surface cone angle, the fifth eccentricity between the valve stem axis and the valve plate sealing surface axis, and the sixth eccentricity between the valve seat sealing surface axis and the valve body channel axis.

2. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 1, characterized in that, The worm gear transmission mechanism includes a worm gear box (4), a box cover (5), a worm wheel, and a worm; one end of the worm is fixedly connected to the input shaft (3), and the worm meshes with the worm wheel for transmission; the worm wheel is fixedly mounted on the upper end of the valve stem (10); the box cover (5) is fixedly installed on the top of the worm gear box (4) by box cover fixing bolts.

3. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 2, characterized in that, An upper bearing is provided between the valve stem (10) and the worm gear box (4), and a lower bearing is provided between the valve stem (10) and the valve body; the upper bearing and the lower bearing respectively support the upper and lower parts of the valve stem (10).

4. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 3, characterized in that, An upper valve stem sealing assembly is provided between the valve stem (10) and the worm gear box (4), and a lower valve stem sealing assembly is provided between the valve stem (10) and the valve body; the upper valve stem sealing assembly is located below the upper bearing, and the lower valve stem sealing assembly is located above the lower bearing.

5. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 1, characterized in that, The valve plate is fixedly installed at the lower end of the valve stem (10) by a valve plate pressure plate and valve plate fixing bolts; the sealing surface of the valve plate is a hardened metal conical surface.

6. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 1, characterized in that, The sealing surface of the metal valve seat is a hardened metal conical surface; a sealing gasket is provided between the metal valve seat and the valve body.

7. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 2, characterized in that, The top of the worm gear box (4) is also provided with an opening indicator mechanism; the opening indicator mechanism includes an opening indicator plate and an indicator pointer; the indicator pointer is fixedly installed on the top of the valve stem (10), and the opening indicator plate is fixedly installed on the box cover (5).

8. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 1, characterized in that, The lower end of the valve body is provided with a lower valve stem bearing seat; a bearing supporting the lower end of the valve stem (10) is installed in the lower valve stem bearing seat; the bottom of the lower valve stem bearing seat is fixedly installed with a lower valve stem end cap by end cap fixing bolts.

9. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 1, characterized in that, The valve body adopts an integral casting structure; both ends of the valve body are provided with flange connection structures, and multiple bolt holes are evenly distributed on the flanges.

10. The six-eccentric all-metal hard-on-hard butterfly valve according to claim 1, characterized in that, The center of the valve plate is eccentrically set to the axis of the valve stem (10); during the opening process, the sealing surface of the valve plate is completely separated from the sealing surface of the metal valve seat at the moment of opening, without frictional contact.

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