Anti-clogging gate valve

Abstract

The utility model discloses a prevent stifled gate valve belongs to the technical field of gate valve. The prevent stifled gate valve of the present application is vertically installed in the flue or pipeline, and the valve stem is driven to drive the valve plate to lift through the actuating mechanism, so that the valve plate enters or exits the flow channel of the valve body under the guidance of the valve plate groove, and the cutting edge of the scraper is attached to or keeps the preset gap with the two side guide surfaces of the valve plate, so that the scraper removes the adherend attached to the surface of the valve plate during the lifting movement of the valve plate. The prevent stifled gate valve of the present application can be suitable for high tar, easy caking and bad working conditions, and the tar agglomerates adhered to the valve plate are directly and actively removed through the mechanical scraping mode, which ensures that the valve can continuously and normally operate in the flue gas with high tar content, and fundamentally replaces the easily blocked traditional butterfly valve. The prevent stifled gate valve can effectively solve the blockage and jamming problem caused by tar adhesion and agglomeration, and ensure that the valve realizes automatic control stably and reliably for a long time.

Description

Technical Field

[0001] This application relates to the field of gate valve technology, and in particular to an anti-clogging gate valve. Background Technology

[0002] Gate valves, a common type of shut-off valve, are widely used in fluid pipeline systems in industries such as petroleum, chemical, and metallurgy due to their advantages such as low flow resistance and good sealing performance. Their working principle involves opening and closing the passage through the vertical movement of the valve plate.

[0003] In the carbon materials manufacturing industry, the flue gas produced by anode carbon roasting furnaces has a complex composition, containing a large amount of high-temperature volatiles and viscous tar. As this flue gas flows through subsequent exhaust ducts and treatment systems, the tar components in the flue gas condense and adhere to the inner walls of the ducts and valves as the temperature decreases.

[0004] Currently, in such operating conditions, ordinary gate valves or butterfly valves are mostly used for flow regulation and shut-off. However, both of these valves have significant limitations in practical applications:

[0005] 1. Disadvantages of ordinary gate valves:

[0006] Although ordinary gate valves offer superior sealing performance compared to butterfly valves, the gap between their valve plate and body is narrow. Under conditions of high-tar flue gas, viscous tar easily condenses and accumulates within this gap, on the valve plate surface, and inside the valve cavity, forming hard lumps. These lumps cause significant resistance during valve plate movement, and can even completely jam the valve, rendering it unable to operate. Furthermore, tar lumps can damage the sealing surface between the valve plate and the valve seat, leading to incomplete valve closure and internal leakage. Maintenance personnel must frequently shut down the machine for high-temperature steam purging or manual cleaning using mechanical methods, resulting in harsh working conditions, high maintenance intensity, and severely impacting production continuity and automation levels.

[0007] 2. Disadvantages of butterfly valves:

[0008] Although butterfly valves are simple in structure and low in cost, their valve plates are constantly positioned in the center of the flow channel, directly exposed to the continuous impact of high-speed, tar-laden fumes, making them more prone to contaminant adhesion. Furthermore, the gaps between the valve plate and the valve body, as well as the sealing area around the valve shaft, are high-risk areas for tar buildup. This buildup leads to a sharp increase in valve rotation torque, ultimately causing overload of the actuator and valve blockage, thus preventing reliable closure and precise automated control. Utility Model Content

[0009] To address the aforementioned issues, a solution is provided that can adapt to harsh working conditions characterized by high tar content and easy agglomeration, effectively solving the blockage and jamming problems caused by tar adhesion and agglomeration, and ensuring long-term stable and reliable automated control of the valve.

[0010] This application discloses an anti-clogging gate valve, vertically installed in a flue or pipeline, comprising: a valve body, a valve plate disposed within a flow channel of the valve body, a valve stem connected to the valve plate, and an actuator for driving the valve stem to move the valve plate up and down, so that the valve plate enters or exits the flow channel of the valve body under the guidance of the valve plate groove, and further comprising:

[0011] A scraper is located on the inner wall of the valve body and is symmetrically arranged at the entrance of the valve plate groove. The cutting edge of the scraper is in contact with or maintains a preset gap with the guide surfaces on both sides of the valve plate so that the scraper removes the adhering substances on the surface of the valve plate during the lifting and lowering movement of the valve plate.

[0012] Optionally, the blade surface of the scraper is coated with a polytetrafluoroethylene coating or a hard chrome plating.

[0013] Optionally, the blade of the scraper is a mirror-polished blade.

[0014] Optionally, the blade of the scraper is inclined at an angle relative to the direction of movement of the valve plate to form an inclined surface that guides the scraped-off deposits to slide down.

[0015] Optionally, the blade bevel of the scraper is inclined from top to bottom away from the valve plate.

[0016] Optionally, the scraper is engaged with the valve plate groove.

[0017] Optional, also includes:

[0018] A packing groove is provided in the area above the valve plate groove for the valve stem to pass through;

[0019] A sealing packing is provided inside the packing groove;

[0020] A packing gland is disposed on the outside of the sealing packing and is fixed to the upper end of the packing groove. The packing gland has a through hole that matches the cross-section of the valve plate.

[0021] Optionally, the sealing packing includes a first packing and a second packing, with the first packing located above the second packing.

[0022] Optionally, the first packing is graphite packing, and the second packing is packing wrapped with metal wire.

[0023] Optionally, a hard seal is formed between the valve plate and the valve body.

[0024] The beneficial effects of the above technical solution are as follows:

[0025] In this technical solution, the anti-clogging gate valve is vertically installed in the flue or pipeline. An actuator drives the valve stem to raise and lower the valve plate, allowing it to enter or exit the flow channel of the valve body under the guidance of the valve plate groove. The scraper's cutting edge is in contact with or maintains a preset gap with the guide surfaces on both sides of the valve plate, thus removing adhering substances from the valve plate surface during its raising and lowering motion. This anti-clogging gate valve is suitable for harsh working conditions with high tar content and easy agglomeration. Through mechanical scraping, it directly and actively removes tar clumps adhering to the valve plate, ensuring continuous normal operation of the valve in flue gas with high tar content (such as in the exhaust gas conditions of an anode carbon roasting furnace), fundamentally replacing the easily clogged traditional butterfly valve. It effectively solves the problems of clogging and jamming caused by tar adhesion and agglomeration, ensuring long-term stable and reliable automated control of the valve. Attached Figure Description

[0026] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0027] Figure 1 This is a front view of one embodiment of the anti-clogging gate valve described in this application;

[0028] Figure 2 for Figure 1 The left view;

[0029] Figure 3 for Figure 1 Top view;

[0030] Figure 4 for Figure 1 A three-dimensional image. Detailed Implementation

[0031] The advantages of this application are further illustrated below with reference to the accompanying drawings and specific embodiments.

[0032] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0033] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0034] It should be understood that although the terms first, second, third, etc., may be used in this disclosure to describe various information, such information should not be limited to these terms. These terms are used only to distinguish information of the same type from one another. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0035] In the description of this application, it should be understood that the numerical labels before the steps do not indicate the order of the steps, but are only used to facilitate the description of this application and to distinguish each step, and therefore should not be construed as a limitation of this application.

[0036] See Figures 1-4 As shown, this embodiment provides an anti-clogging gate valve, vertically installed in a flue or pipeline, including: a valve body 6, a valve plate 3 disposed in the flow channel of the valve body 6, a valve stem 2 connected to the valve plate 3, and an actuator 1 that drives the valve stem 2 to move the valve plate 3 up and down, so that the valve plate 3 enters or exits the flow channel of the valve body 6 under the guidance of the valve plate groove, and further includes:

[0037] The scraper 5 is located on the inner wall of the valve body 6 and is symmetrically arranged at the entrance of the valve plate groove. The cutting edge of the scraper 5 is in contact with or maintains a preset gap with the guide surfaces on both sides of the valve plate 3, so that during the lifting and lowering movement of the valve plate 3, the scraper 5 scrapes off the adhering material on the surface of the valve plate 3, which falls off under the action of gravity and is carried away by the flowing air.

[0038] As an example, not a limitation, the scraper 5 is semi-circular to match the movement trajectory of the valve plate 3, achieving scraping without dead angles. During the raising and lowering of the gate valve's valve plate 3, the guide surfaces on both sides move vertically. A semi-circular scraper 5, with its cutting edge curve, can maintain optimal contact or a constant gap with the valve plate 3 throughout its entire raising and lowering stroke from fully closed to fully open. In contrast, a straight rectangular scraper 5 only achieves ideal contact with the valve plate 3 when it reaches a specific position. At other positions, the contact effect deteriorates, easily leaving cleaning dead angles. The semi-circular design ensures uniform, efficient, and thorough scraping throughout the entire stroke of the valve plate 3.

[0039] In this embodiment, the anti-clogging gate valve is vertically installed in the flue or pipeline. The actuator 1 drives the valve stem 2 to raise and lower the valve plate 3, allowing the valve plate 3 to enter or exit the flow channel of the valve body 6 under the guidance of the valve plate groove. The cutting edge of the scraper 5 is in contact with or maintains a preset gap with the guide surfaces on both sides of the valve plate 3, thereby scraping away the deposits adhering to the surface of the valve plate 3 during its raising and lowering motion. The anti-clogging gate valve of this application is suitable for harsh working conditions with high tar content and easy agglomeration. Through mechanical scraping, it directly and actively removes tar deposits adhering to the valve plate 3, ensuring continuous normal operation of the valve in flue gas with high tar content (such as the exhaust gas from an anode carbon roasting furnace), fundamentally replacing the easily clogged traditional butterfly valve.

[0040] In a preferred embodiment, the cutting edge surface of the scraper 5 is coated with a polytetrafluoroethylene (PTFE) coating or a hard chrome plating.

[0041] By adopting the above coating, the problem of secondary adhesion of tar and other contaminants on the surface of the scraper 5 after scraping can be effectively solved, ensuring the scraper's long-lasting and efficient scraping ability.

[0042] When using a polytetrafluoroethylene (PTFE) coating, its main advantages are: Extreme non-stickiness: PTFE has the lowest surface energy of all solid materials, making it extremely difficult for sticky substances such as tar to wet and adhere to its surface. Even if scraped-off tar comes into contact with the blade edge, it cannot adhere firmly and can automatically fall off under gravity or airflow, effectively preventing the scraper itself from becoming a clogging point and achieving a self-cleaning function. Reduced friction and drag: The PTFE coating has an extremely low coefficient of friction, which can significantly reduce the frictional resistance between the scraper edge 5 and the valve plate 3 surface, reducing the load on the actuator 1 and mitigating wear on both. Chemical corrosion resistance: PTFE is inert to most chemicals, resisting corrosive components such as sulfides and acidic condensates that may be present in the flue gas, protecting the base material, and extending the coating's shelf life.

[0043] When using hard chrome plating, its main advantages are: high hardness and wear resistance: the Vickers hardness of hard chrome can reach HV900-1200, which can withstand the strong scraping and wear of hard particles in tar agglomerates, greatly extending the service life of the scraper and preventing the cutting edge from becoming dull. Good surface properties: the chrome-plated surface is smooth and dense, achieving a near-mirror finish with low porosity, which not only reduces the coefficient of friction but also reduces tar adhesion, making it easy to remove, thus meeting both wear resistance and anti-sticking requirements.

[0044] This embodiment improves the adaptability, durability and reliability of the scraper 5 under harsh working conditions through targeted surface treatment, which is one of the key designs to ensure the long-term stable operation of the valve.

[0045] In a preferred embodiment, the cutting edge of the scraper 5 is mirror-polished. This treatment gives the cutting edge an extremely high degree of smoothness, offering the following advantages:

[0046] Anti-stick and self-cleaning: The extremely low surface roughness reduces the adhesion anchor points of sticky substances such as tar, effectively preventing the scraped material from adhering to the blade edge again, and ensuring the continuous self-cleaning ability of scraper 5.

[0047] Friction reduction and wear reduction: The highly smooth cutting edge significantly reduces the coefficient of friction with the surface of the valve plate 3, which reduces the movement resistance of the valve plate 3, reduces the load on the actuator 1, reduces wear on both, and extends service life.

[0048] Corrosion resistance and durability: Polishing eliminates microscopic surface defects, reduces the accumulation and erosion of corrosive media, and enhances the cutting edge's resistance to acidic components in flue gas.

[0049] Highly efficient scraping: The smooth and hard blade makes the scraping action smoother and more efficient, and can more completely remove tar clumps on the surface of valve plate 3, reduce residue, and help maintain valve sealing stability.

[0050] This mirror polishing process, through physical surface optimization, comprehensively improves the anti-sticking, wear-resistant, and corrosion-resistant properties of scraper 5, and is one of the key designs for its adaptability to harsh working conditions with high tar content.

[0051] In a preferred embodiment, the blade of the scraper 5 is inclined at an angle relative to the direction of movement of the valve plate 3 to form an inclined surface that guides the scraped-off attachment to slide down.

[0052] In this embodiment, the inclined surface provides a clear, downward guiding path for the scraped-off tar chunks. This structure makes full use of gravity, causing the contaminants to slide naturally down the inclined surface, effectively preventing the accumulation of contaminants on the back of the scraper 5 and at the bottom of the cavity of the valve body 6, and eliminating secondary blockages caused by poor slag discharge.

[0053] Furthermore, the beveled edge of the scraper 5 is inclined from top to bottom away from the valve plate 3.

[0054] In this embodiment, the valve plate 3 adopts a directional inclined design. The inclined blade can effectively decompose the vertical force of the valve plate 3 during the scraping process, generating a component force perpendicular to the adhesion surface. This is more conducive to cutting into and prying hard tar clumps. Compared with a vertical blade, scraping is more labor-saving and thorough, thus optimizing the scraping force direction and improving scraping efficiency. The arrangement of the blade from top to bottom away from the valve plate 3 (usually a negative rake angle structure) makes the blade edge thicker, enhancing its strength and rigidity. This allows it to withstand greater impact force and bending moment when scraping hard clumps, and its wear resistance and impact resistance are significantly better than a thin and sharp vertical blade, thereby extending the overall replacement cycle of the scraper 5.

[0055] In a preferred embodiment, the scraper 5 is engaged with the valve plate groove.

[0056] In this embodiment, the scraper 5 is installed on the valve plate groove using a snap-fit ​​method, which facilitates disassembly, replacement, and subsequent maintenance. During operation, the valve experiences temperature changes and airflow impacts, resulting in thermal expansion and contraction and slight vibrations. The snap-fit ​​method provides sufficient installation rigidity while allowing for a small amount of adaptive displacement between the scraper 5 and the mounting groove. This avoids thermal stress concentration or fatigue fracture at the connection point that may occur with a rigid connection, thus improving long-term operational reliability.

[0057] In a preferred embodiment, the anti-clogging gate valve may further include:

[0058] A packing groove is provided in the area above the valve plate groove through which the valve stem 2 passes;

[0059] A sealing packing is provided inside the packing groove;

[0060] The packing gland 4 is located on the outside of the sealing packing and is fixed to the upper end of the packing groove. The packing gland 4 has a through hole that matches the cross-section of the valve plate 3. The packing gland 4 is connected to the packing box by screws and threads.

[0061] Furthermore, the sealing packing includes a first packing and a second packing, with the first packing located above the second packing.

[0062] Specifically, the first packing is made of graphite, and the second packing is made of packing wrapped with metal wire.

[0063] In this embodiment, a dual-sealing structure achieves comprehensive protection for both dynamic and static conditions. The upper first packing (graphite packing) possesses excellent self-lubricating properties and thermal stability, ensuring smooth movement of the valve plate during frequent lifting and lowering, a low coefficient of friction, and resistance to the high temperatures of flue gas without failure due to heat. It primarily performs dynamic sealing and high-temperature resistance functions. The lower second packing (outer wire packing), where "outer wire" typically refers to an inner layer of flexible materials such as graphite or asbestos, covered with an outer layer of metal wire (such as stainless steel wire or Monel alloy wire), provides extremely high structural strength and pressure resistance. This allows the packing to effectively resist system pressure fluctuations and impacts, preventing it from being squeezed out of the stuffing box by the high-pressure medium, and providing robust back support for the main seal. It focuses more on static sealing and pressure resistance. This combination forms a gradient sealing system. The lower metal wire packing acts as a robust "shield" to withstand the main pressure, while the upper graphite packing acts as a flexible "barrier" to ensure dynamic sealing and temperature resistance. The two work together to achieve a sealing effect greater than the sum of their parts, far exceeding that of packing made of a single material.

[0064] In a preferred embodiment, a hard seal is formed between the valve plate 3 and the valve body 6.

[0065] In this embodiment, the hard seal provides unparalleled durability, temperature resistance, erosion resistance, and sealing reliability compared to the soft seal, and works in conjunction with the scraper system to fundamentally ensure that the valve can achieve long-term, stable, maintenance-free automated operation throughout its entire life cycle.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An anti-clogging gate valve, vertically installed in a flue or pipe, comprising: The valve body, a valve plate disposed within the flow channel of the valve body, a valve stem connected to the valve plate, and an actuator for driving the valve stem to raise or lower the valve plate, so that the valve plate enters or exits the flow channel of the valve body under the guidance of the valve plate groove, characterized in that it further includes: A scraper is located on the inner wall of the valve body and is symmetrically arranged at the entrance of the valve plate groove. The cutting edge of the scraper is in contact with or maintains a preset gap with the guide surfaces on both sides of the valve plate so that the scraper removes the adhering substances on the surface of the valve plate during the lifting and lowering movement of the valve plate.

2. The anti-clogging gate valve according to claim 1, characterized in that, The blade surface of the scraper is coated with a polytetrafluoroethylene coating or a hard chrome plating.

3. The anti-clogging gate valve according to claim 1, characterized in that, The blade of the scraper has a mirror-polished edge.

4. The anti-clogging gate valve according to claim 1, characterized in that, The blade of the scraper is inclined at an angle relative to the direction of movement of the valve plate, so as to form an inclined surface that guides the scraped-off attachment to slide down.

5. The anti-clogging gate valve according to claim 4, characterized in that, The blade of the scraper slopes from top to bottom away from the valve plate.

6. The anti-clogging gate valve according to claim 1, characterized in that, The scraper is engaged with the valve plate groove.

7. The anti-clogging gate valve according to claim 1, characterized in that, Also includes: A packing groove is provided in the area above the valve plate groove for the valve stem to pass through; A sealing packing is provided inside the packing groove; A packing gland is disposed on the outside of the sealing packing and is fixed to the upper end of the packing groove. The packing gland has a through hole that matches the cross-section of the valve plate.

8. The anti-clogging gate valve according to claim 7, characterized in that, The sealing packing includes a first packing and a second packing, with the first packing located above the second packing.

9. The anti-clogging gate valve according to claim 8, characterized in that, The first packing is made of graphite, and the second packing is made of metal wire.

10. The anti-clogging gate valve according to claim 1, characterized in that, A hard seal is formed between the valve plate and the valve body.

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