A new type of double-seal flat gate valve for oil and gas and offshore platforms

Abstract

The present application relates to the field of fluid control, and provides a novel double-seal flat gate valve for oil and gas and offshore platforms, which comprises a valve body and a support, the valve body is connected to the support, a valve stem, a hand wheel and a valve stem nut body are connected to the support, the valve stem and the valve stem nut body are threadedly connected, the valve stem is connected to the hand wheel, and a valve torque reducing mechanism is arranged on the valve stem nut body; a gate plate and a valve seat are connected to the valve body, the gate plate is connected to the valve stem, and a cleaning and soft-hard composite sealing mechanism is arranged on the valve seat. The present application can reduce the valve torque, reduce the energy consumption, and also can realize the soft-hard sealing and scraping of the attachments in the sealing area.

Description

Technical Field

[0001] This invention relates to the field of fluid control technology, specifically to a novel double-sealed flat gate valve for oil and gas applications and offshore platforms. Background Technology

[0002] Flat gate valves are commonly used fluid control devices. They open and close the medium passage through the lifting and lowering movement of the gate. They are characterized by low flow resistance and suitability for fully open or fully closed conditions, and are widely used in oil and gas transportation and offshore platform pipeline systems. Due to the complex working environment of oil and gas and offshore platforms, valves typically need to withstand long-term medium pressure, frequent opening and closing, and the influence of external environmental factors. Therefore, high requirements are placed on the valve's opening and closing performance, sealing performance, and reliability.

[0003] When existing flat gate valves are opened or closed, the valve stem nut and other transmission components need to withstand a large axial load. The relevant contact parts are prone to generating large frictional resistance. Especially when the valve is used for a long time, the internal pressure is high, or there is a certain force imbalance in the relevant transmission components, the valve opening and closing torque can increase. This requires the operator to apply a large force, which not only affects the convenience of opening and closing the valve, but also increases the load and energy consumption of the drive mechanism. Long-term operation can also accelerate the wear of the relevant transmission components, thereby affecting the service life of the valve.

[0004] Meanwhile, existing flat gate valves typically rely on the fit between the valve seat and corresponding sealing components to achieve sealing in the closed state. During long-term transportation of oil and gas media, particles, impurities, or deposits in the media can easily adhere to the sealing surfaces. When the valve is opened and closed again, these deposits can easily enter the sealing contact area, creating local gaps between the sealing surfaces, and even causing scratches and wear on the sealing components, thus leading to a decrease in sealing performance. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention aims to provide a novel double-seal flat gate valve for oil and gas applications and offshore platforms. To solve these problems, this invention employs the following technical solution: A novel double-seal flat gate valve for oil and gas and offshore platforms includes a valve body and a support. The valve body is connected to the support, and a valve stem, a handwheel and a valve stem nut are connected to the support. The valve stem and the valve stem nut are threaded together, the valve stem and the handwheel are connected, and a valve torque reduction mechanism is provided on the valve stem nut. The valve body is connected to a gate and a valve seat. The gate is connected to the valve stem. The valve seat is equipped with a cleaning and soft-hard composite sealing mechanism.

[0006] Optionally, the valve torque reduction mechanism includes an upper spherical surface of the valve stem nut and a lower spherical surface of the valve stem nut. The upper spherical surface of the valve stem nut is located on the top wall of the horizontal section of the valve stem nut body, and the lower spherical surface of the valve stem nut is located on the bottom wall of the horizontal section of the valve stem nut body.

[0007] Optionally, the cleaning and soft-hard composite sealing mechanism includes a grease injection hole, a graphite ring, an O-ring, a soft sealing ring, and a hardened component. The grease injection hole is located on the valve seat, the graphite ring is connected between the valve seat and the valve body, the O-ring is connected between the valve seat and the valve body, the soft sealing ring is connected between the valve seat and the gate, and the hardened component is connected to the valve seat and located between the valve seat and the gate. The hardened component has a scraping groove.

[0008] Optionally, the material of the hard surface component is hard metal.

[0009] Optionally, the scraper groove is provided with a sharp part.

[0010] Optionally, an O-ring is connected to the valve stem nut body.

[0011] Optionally, the soft sealing ring may be made of PTFE.

[0012] Optionally, the valve seat is connected to the valve body via an elastic element.

[0013] Optionally, a valve stem nut cover is connected to the bracket, and the valve stem nut cover abuts against the valve stem nut body.

[0014] Optionally, the valve seat material may include fire-resistant material and anti-static material.

[0015] The present invention has the following beneficial effects: In the valve opening and closing process, this invention improves the stress and transmission state of the valve stem nut body by utilizing the upper and lower spherical surfaces of the valve stem nut to reduce valve torque. Furthermore, it forms a double seal using a soft sealing ring and a hard surface component, and removes deposits from the sealing area during opening and closing through a scraper groove. Simultaneously, an elastic component provides elastic pre-tightening and compensation to the valve seat. The O-ring, graphite ring, and grease injection hole further enhance sealing, temperature resistance, lubrication, and maintenance performance, ensuring that all components work together to improve the sealing reliability and service life of the valve during long-term use. Attached Figure Description

[0016] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.

[0017] Figure 1 This is a structural schematic diagram of a novel double-sealed flat gate valve for oil and gas and offshore platforms according to the present invention; Figure 2 This is the present invention. Figure 1 Enlarged view of point A in the middle; Figure 3 This is the present invention. Figure 1 Enlarged view of point B in the middle.

[0018] Reference numerals: 1. Valve body; 2. Bracket; 3. Valve stem; 4. Handwheel; 5. Valve stem nut body; 51. Valve stem nut gland; 6. Upper spherical surface of valve stem nut; 7. Lower spherical surface of valve stem nut; 8. Gate; 9. Valve seat; 10. Grease injection hole; 11. Graphite ring; 12. O-ring one; 13. Soft sealing ring; 14. Hardened part; 15. Scraper groove; 16. Elastic part. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] In the description of this invention, it should be noted that the terms "vertical," "upper," "lower," and "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or a connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] This invention can be applied to the manufacturing industry, specifically for oil and gas transportation in manufacturing systems on offshore platforms, and also for wastewater control and treatment.

[0023] like Figures 1-3As shown, a novel double-seal flat gate valve for oil and gas and offshore platforms includes a valve body 1 and a bracket 2. The valve body 1 is connected to the bracket 2. The bracket 2 is connected to a valve stem 3, a handwheel 4 and a valve stem nut body 5. The valve stem 3 and the valve stem nut body 5 are threaded together. The valve stem 3 and the handwheel 4 are connected. The valve stem nut body 5 is provided with a valve torque reduction mechanism. A gate 8 and a valve seat 9 are connected to the valve body 1. The gate 8 is connected to the valve stem 3. The valve seat 9 is equipped with a cleaning and soft-hard composite sealing mechanism.

[0024] According to an optional embodiment of the present invention, the valve torque reduction mechanism includes an upper spherical surface 6 and a lower spherical surface 7 of the valve stem nut. The upper spherical surface 6 is located on the top wall of the horizontal section of the valve stem nut body 5, and the lower spherical surface 7 is located on the bottom wall of the horizontal section of the valve stem nut body 5. The upper end of the valve stem nut body 5 contacts the valve stem nut cap 51 through the upper spherical surface 6, and the lower end of the valve stem nut body 5 contacts the bracket 2 through the lower spherical surface 7.

[0025] In a preferred embodiment, the cleaning and soft-hard composite sealing mechanism includes a grease injection hole 10, a graphite ring 11, an O-ring 12, a soft sealing ring 13, and a hardened component 14. The grease injection hole 10 is located on the valve seat 9. The graphite ring 11 is connected between the valve seat 9 and the valve body 1. The O-ring 12 is connected between the valve seat 9 and the valve body 1. The soft sealing ring 13 is connected between the valve seat 9 and the gate 8. The hardened component 14 is connected to the valve seat 9 and is located between the valve seat 9 and the gate 8. The hardened component 14 is provided with a scraping groove 15.

[0026] Optionally, the hard surface member 14 is made of hard metal.

[0027] Optionally, the scraper groove 15 is provided with a sharp part.

[0028] Optionally, an O-ring 2 is connected to the valve stem nut body 5.

[0029] Optionally, the soft sealing ring 13 may be made of PTFE.

[0030] Optionally, the valve seat 9 is connected to the valve body 1 via an elastic element 16.

[0031] Optionally, a valve stem nut cover 51 is connected to the bracket 2, and the valve stem nut cover 51 abuts against the valve stem nut body 5.

[0032] Optionally, the valve seat 9 may be made of fire-resistant material or anti-static material.

[0033] Implementation process: When using this invention, the valve body 1 is first installed in the oil and gas pipeline or the corresponding pipeline on the offshore platform. The valve body 1 is used to form a medium flow channel and to provide an installation and bearing base for the various sealing components and opening and closing components inside the valve.

[0034] The bracket 2 is connected above the valve body 1 to support the valve stem 3, handwheel 4 and valve stem nut body 5, and to keep the valve operating part in a stable relative position with the valve body 1.

[0035] As the main transmission component in the valve opening and closing process, the valve stem 3 is threadedly engaged with the valve stem nut body 5. When relative rotation occurs between the valve stem 3 and the valve stem nut body 5, the rotational motion can be converted into corresponding axial motion through the threaded transmission, thereby realizing the opening or closing of the gate 8.

[0036] The handwheel 4 is connected to the valve stem 3. The operator can input the opening and closing power to the valve stem 3 by turning the handwheel 4. Therefore, the handwheel 4 plays the role of manually applying torque and controlling the opening and closing of the valve.

[0037] The valve stem nut body 5 is used to form a threaded transmission engagement with the valve stem 3 and to transmit and guide the movement of the valve stem 3. At the same time, the valve stem nut body 5 also serves as the mounting base for the valve torque reduction mechanism.

[0038] When the valve is opened or closed by operating the handwheel 4, the valve stem nut body 5, in the process of transmitting axial load, forms a fit with the adjacent structure on the upper and lower sides of its horizontal section through the upper spherical surface 6 and the lower spherical surface 7 of the valve stem nut, respectively.

[0039] The spherical surface 6 on the valve stem nut is located on the top wall of the horizontal section of the valve stem nut body 5. Its spherical structure can form a smoother contact and load transmission when the valve stem nut body 5 is subjected to an upper force, reducing the local resistance caused by factors such as installation deviation and force skew. The lower spherical surface 7 of the valve stem nut is located on the bottom wall of the horizontal section of the valve stem nut body 5. It supports the valve stem nut body 5 when it is subjected to an axial force in another direction, and improves the stress state through the spherical fit. The upper spherical surface 6 and the lower spherical surface 7 of the valve stem nut form a fit from the upper and lower sides of the valve stem nut body 5, respectively. This ensures that the valve stem nut body 5 can obtain corresponding support when transmitting opening and closing loads in both positive and negative directions, reducing the additional friction caused by off-center loading at the contact points. This makes the movement of the valve stem 3 by the handwheel 4 smoother, thereby reducing the valve opening and closing torque and reducing operating energy consumption.

[0040] When the valve is opened or closed, the valve stem 3 drives the associated gate plate 8 to move, gradually opening or closing the medium passage inside the valve body 1. When the valve is closed, the main seal is formed by the cleaning and soft-hard composite sealing mechanism at the valve seat 9.

[0041] The valve seat 9 is connected inside the valve body 1 and is used to form a sealing support surface and sealing installation base when the valve is closed. It also supports components such as the grease injection hole 10, graphite ring 11, O-ring 12, soft sealing ring 13, hard surface part 14, and elastic part 16, so that the above components can form a multi-stage sealing and cleaning structure around the valve seat 9.

[0042] The grease injection hole 10 is located on the valve seat 9 and is used to replenish sealing grease or lubricating grease to the corresponding sealing area of ​​the valve seat 9. After the valve has been running for a long time, the corresponding medium can be injected into the sealing part through the grease injection hole 10, allowing the sealing grease to enter the mating area near the valve seat 9. On the one hand, this lubricates the relatively moving and contacting parts, reducing friction and wear during opening and closing. On the other hand, when the sealing components experience a certain degree of wear or a decrease in sealing performance, the injected sealing grease can help fill local small gaps, thereby helping to maintain the valve's sealing performance. The grease injection hole 10 also allows for lubrication and maintenance of the valve without complete disassembly, facilitating later inspection and maintenance.

[0043] A graphite ring 11 is disposed between the valve seat 9 and the valve body 1 to form a high-temperature resistant seal in the connection area between the valve seat 9 and the valve body 1. Graphite material has good high-temperature resistance. Under normal operating conditions, the graphite ring 11 can help prevent the medium from leaking from the mating gap between the valve seat 9 and the valve body 1. When the valve is in an environment with high temperatures or even a fire, the graphite ring 11 can still continue to perform its corresponding sealing function, thereby improving the safety and sealing reliability of the valve in oil and gas and offshore platform applications.

[0044] O-ring 12 is also disposed between valve seat 9 and valve body 1 to provide an elastic seal for the connection gap between valve seat 9 and valve body 1. Under normal operating conditions, O-ring 12 can conform to the corresponding mating surface through its own elastic deformation, sealing the mating gap and reducing the possibility of media leakage outward along the periphery of valve seat 9. O-ring 12 and graphite ring 11 form a mutually mating sealing relationship, so that valve seat 9 and valve body 1 do not rely on a single sealing element for sealing, which helps to improve the sealing reliability of this part.

[0045] A soft sealing ring 13 is disposed between the valve seat 9 and the gate 8, and the soft sealing ring 13 is made of PTFE. Utilizing the sealing adaptability of PTFE, the soft sealing ring 13 can form a tight seal with the mating surfaces after the corresponding components are compressed, thus constituting a soft seal. The soft sealing ring 13 is mainly used to compensate for small gaps on the mating surfaces, enabling a better sealing effect when the valve is closed and reducing the possibility of media leakage through the sealing contact area. At the same time, the PTFE material also reduces friction at the sealing contact points, which helps to reduce wear on the soft sealing ring 13 during the movement of the corresponding components.

[0046] The hardened component 14 is connected to the valve seat 9 and located between the valve seat 9 and the gate 8. Made of hard metal, the hardened component 14 forms a hard-seal contact area distinct from the soft-seal ring 13. When the valve is closed, the hardened component 14 forms a sealing fit with the corresponding moving parts through its hard surface, further forming a hard seal on top of the soft seal created by the soft-seal ring 13, thus constituting a dual-seal structure. Even when the sealing capacity of the soft-seal ring 13 decreases due to long-term use, temperature changes, or other factors, the hardened component 14 can still provide a corresponding sealing effect, thereby improving the reliability of the overall valve sealing structure.

[0047] The hardened component 14 is provided with a scraper groove 15, which has a sharp edge. When the valve operates for extended periods in oil or gas media, particles, dirt, scale, or other deposits may adhere to the corresponding moving surfaces. During valve opening and closing, the moving parts move relative to the hardened component 14. When the deposits pass the location of the scraper groove 15, the sharp edge of the scraper groove 15 can scrape the deposits on the moving surfaces, causing them to detach from the sealing mating surfaces. Therefore, the scraper groove 15 not only reduces the entry of dirt into the main sealing contact area between the soft sealing ring 13 and the hardened component 14, but also reduces the possibility of particles or deposits being trapped between the sealing surfaces, causing scratches, localized lifting, and incomplete closure. Thus, the hardened component 14 simultaneously provides both a hard seal and cleans the sealing surface.

[0048] The elastic element 16 connects the valve seat 9 and the valve body 1. The elastic element 16 can be a spring coil. The elastic element 16 uses its own elasticity to apply a corresponding elastic force to the valve seat 9, so that the valve seat 9 can maintain a certain pre-tightening tendency in the sealing mating direction. When the valve is closed, the elastic element 16 can make the valve seat 9 and the soft sealing ring 13 and hard surface member 14 provided on the valve seat 9 more reliably fit against the corresponding sealing mating surface, so as to maintain the contact pressure required by the sealing structure. When the sealing components undergo a certain degree of wear after long-term operation or there are small changes in the assembly dimensions, the elastic element 16 can also use its own elastic deformation to compensate for the corresponding displacement, thereby reducing the problem of sealing pressure drop caused by wear or dimensional changes.

[0049] When the valve needs to be closed, the operator turns the handwheel 4, which transmits torque to the valve stem 3. The valve stem 3 and the valve stem nut body 5 generate a corresponding transmission action through threaded engagement. During this process, the upper spherical surface 6 and the lower spherical surface 7 of the valve stem nut support the valve stem nut body 5 according to the direction of force, enabling the valve stem nut body 5 to transmit the load relatively stably and reducing the additional friction caused by off-center loading. As the valve stem 3 continues to move, the corresponding opening and closing structure inside the valve gradually enters the closed position. When approaching the fully closed position, the scraper groove 15 first scrapes and cleans the mating surfaces passing by it, either directly or with relative movement, removing or removing any dirt that may be attached to the sealing area from the main sealing position. Subsequently, the soft sealing ring 13 fits into the corresponding mating surface, forming a soft seal through its own material properties, while the hard surface part 14 forms a hard seal through its hard contact surface, thus creating a dual sealing effect of soft and hard seals working together.

[0050] Meanwhile, the elastic element 16 continuously provides elastic force to the valve seat 9, enabling the valve seat 9 to maintain a pressing tendency towards the sealing mating surface, thereby ensuring that the soft sealing ring 13 and the hard surface element 14 have corresponding sealing contact pressure. The valve seat 9 and the valve body 1 are further sealed by the O-ring 12 and the graphite ring 11. The O-ring 12 mainly provides elastic sealing under normal operating conditions, while the graphite ring 11 further provides corresponding temperature-resistant sealing protection, thereby further reducing the possibility of media leakage from the periphery of the valve seat 9.

[0051] When the valve needs to be opened, turn the handwheel 4 in the opposite direction, causing the valve stem 3 to move in the opposite direction to the closing process. This gradually releases the pressure on the sealing parts, opening the medium passage. During the opening process, the scraper groove 15 on the hardened part 14 can still scrape away any adhering material passing by as the relative movement occurs, thus the opening and closing motion itself also has a certain cleaning effect on the sealing surface. After multiple openings and closings, if the sealing area requires maintenance, grease or lubricating grease can be added to the corresponding area of ​​the valve seat 9 through the grease injection hole 10 to improve the lubrication of the mating parts and assist in the sealing condition, reducing wear caused by long-term operation.

[0052] In addition, an O-ring 2 is connected to the valve stem nut body 5. The O-ring 2 is used to seal the corresponding connection position of the valve stem nut body 5, reducing the entry of external moisture, dust and other impurities into the corresponding mating area, and reducing the possibility of internal lubricating medium leaking out from this point. This helps to maintain a long-term stable mating state between the valve stem nut body 5 and related components.

[0053] The valve seat 9 is made of materials including fire-resistant and anti-static materials, so that in addition to undertaking the functions of sealing installation, support and sealing load transmission, the valve seat 9 can also meet the requirements of oil and gas and offshore platform environments for fire-resistant and anti-static performance, and improve the applicability of the valve in flammable and explosive media transportation environments.

[0054] Therefore, during the valve opening and closing process, this invention improves the force and transmission state of the valve stem nut body 5 by utilizing the upper spherical surface 6 and the lower spherical surface 7 of the valve stem nut to reduce valve torque. On the other hand, it forms a double seal of soft and hard by utilizing the soft sealing ring 13 and the hard surface part 14, and scrapes off the attached material in the sealing area during the opening and closing process by the scraping groove 15. At the same time, the elastic part 16 provides elastic pre-tightening and compensation for the valve seat 9. The O-ring 12, graphite ring 11 and grease injection hole 10 further improve the sealing, temperature resistance, lubrication and maintenance performance, so that the various structures cooperate with each other, thereby improving the sealing reliability and service life of the valve during long-term use.

[0055] The components, modules, mechanisms, and devices in this invention that are not described in detail are all general standard parts or components known to those skilled in the art. Their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A novel double-seal flat gate valve for oil and gas applications and offshore platforms, characterized in that, It includes a valve body (1) and a bracket (2). The valve body (1) is connected to the bracket (2). The bracket (2) is connected to a valve stem (3), a handwheel (4) and a valve stem nut body (5). The valve stem (3) and the valve stem nut body (5) are threaded together. The valve stem (3) and the handwheel (4) are connected. The valve stem nut body (5) is provided with a valve torque reduction mechanism. A gate (8) and a valve seat (9) are connected to the valve body (1). The gate (8) is connected to the valve stem (3). The valve seat (9) is equipped with a cleaning and soft-hard composite sealing mechanism.

2. The novel double-seal flat gate valve for oil and gas and offshore platforms according to claim 1, characterized in that, The valve torque reduction mechanism includes an upper spherical surface (6) of the valve stem nut and a lower spherical surface (7) of the valve stem nut. The upper spherical surface (6) of the valve stem nut is located on the top wall of the horizontal section of the valve stem nut body (5), and the lower spherical surface (7) of the valve stem nut is located on the bottom wall of the horizontal section of the valve stem nut body (5).

3. A novel double-seal flat gate valve for oil and gas and offshore platforms according to claim 2, characterized in that, The cleaning and soft-hard composite sealing mechanism includes a grease injection hole (10), a graphite ring (11), an O-ring (12), a soft sealing ring (13), and a hard surface part (14). The grease injection hole (10) is opened on the valve seat (9). The graphite ring (11) is connected between the valve seat (9) and the valve body (1). The O-ring (12) is connected between the valve seat (9) and the valve body (1). The soft sealing ring (13) is connected between the valve seat (9) and the gate (8). The hard surface part (14) is connected to the valve seat (9) and is located between the valve seat (9) and the gate (8). The hard surface part (14) is provided with a scraper groove (15).

4. A novel double-seal flat gate valve for oil and gas and offshore platforms according to claim 3, characterized in that, The hard surface component (14) is made of hard metal.

5. A novel double-seal flat gate valve for oil and gas and offshore platforms according to claim 3, characterized in that, The scraper groove (15) is provided with a sharp part.

6. A novel double-seal flat gate valve for oil and gas and offshore platforms according to claim 3, characterized in that, The valve stem nut body (5) is connected to an O-ring 2.

7. A novel double-seal flat gate valve for oil and gas and offshore platforms according to claim 3, characterized in that, The soft sealing ring (13) is made of PTFE.

8. A novel double-seal flat gate valve for oil and gas and offshore platforms according to claim 3, characterized in that, The valve seat (9) is connected to the valve body (1) via an elastic element (16).

9. A novel double-seal flat gate valve for oil and gas and offshore platforms according to claim 8, characterized in that, A valve stem nut cover (51) is connected to the bracket (2), and the valve stem nut cover (51) and the valve stem nut body (5) abut against each other.

10. A novel double-sealed flat gate and valve for oil and gas and offshore platforms according to any one of claims 1-9, characterized in that, The valve seat (9) is made of fireproof material and antistatic material.

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