Butterfly valve capable of reducing negative pressure in valve rod area

Abstract

The utility model relates to the technical field of butterfly valves, in particular to a butterfly valve capable of reducing negative pressure in a valve rod area. The butterfly valve capable of reducing the negative pressure in the valve rod area comprises a valve body, a valve rod and a butterfly plate assembly, a valve cavity is formed in the valve body, the valve rod penetrates through the valve cavity in the radial direction of the valve cavity, the butterfly plate assembly is connected to the valve rod, the valve rod is used for driving the butterfly plate assembly to close or open the valve cavity, and the butterfly plate assembly comprises a butterfly plate body and a flow stabilizing plate; the flow stabilizing plate is arranged on the face, connected with the valve rod, of the butterfly plate body, the side, connected with the valve rod, of the flow stabilizing plate is flush with the top face, protruding out of the butterfly plate body, of the valve rod, and the flow stabilizing plate is used for preventing flowing media from making contact with the valve rod in the flowing direction. According to the technical scheme, the negative pressure area on the side of the valve rod can be transferred, negative pressure generated by rapid flowing of fluid can be reduced, and a series of electrical faults caused by the fact that air continuously enters equipment and is gradually accumulated due to poor sealing performance of the valve rod are prevented.

Description

Technical Field

[0001] This disclosure relates to the field of butterfly valve technology, and in particular to a butterfly valve that reduces negative pressure in the valve stem region. Background Technology

[0002] Butterfly valves have a wide range of applications, including power, metallurgy, heating, and petroleum industries. They are used to regulate and control fluid flow in pipelines. The flow is controlled by rotating a butterfly plate within the pipeline. When the butterfly plate rotates to a position perpendicular to the pipeline axis, the fluid flow can be completely cut off, enabling pipeline isolation or maintenance.

[0003] For example, in a transformer, due to the protrusion of the valve stem inside the butterfly valve, the flow velocity of the transformer oil suddenly increases when passing through the valve stem. According to Bernoulli's principle, the pressure is lower where the flow velocity is higher. Therefore, a negative pressure area is formed near the valve stem. If the valve stem is not properly sealed, air will enter the transformer oil due to the negative pressure. This continuous influx of air into the transformer can easily lead to a decrease in the insulation performance of the transformer oil, causing a transformer accident. Furthermore, air will gradually accumulate in the gas relay. When the amount of gas reaches a certain level, it will cause the transformer gas relay to trip, triggering an alarm. If the cause of the trip is not addressed in time, the gas may continue to accumulate, eventually leading to a high-pressure trip, causing the transformer to trip and resulting in more serious equipment damage. Therefore, it is evident that the negative pressure problem generated by the transformer butterfly valve under high-speed oil flow can easily lead to serious consequences. Utility Model Content

[0004] This disclosure aims to address at least one of the technical problems existing in the prior art or related technologies.

[0005] Therefore, in a first aspect of this disclosure, a butterfly valve for reducing negative pressure in the valve stem region is provided, comprising a valve body, a valve stem, and a butterfly plate assembly. A valve cavity is formed within the valve body, and the valve stem passes radially through the valve cavity. The butterfly plate assembly is connected to the valve stem, and the valve stem is used to actuate the butterfly plate assembly to close or open the valve cavity. The butterfly plate assembly includes a butterfly plate body and a flow stabilizer plate. The flow stabilizer plate is disposed on the side of the butterfly plate body connected to the valve stem, and the side of the flow stabilizer plate connected to the valve stem is flush with the top surface of the valve stem protruding from the butterfly plate body. The flow stabilizer plate is used to prevent the flowing medium from contacting the valve stem along the flow direction.

[0006] In one feasible implementation, the valve stem defines the butterfly plate body as a first plate and a second plate, and the flow stabilizer is respectively disposed on the first plate and the second plate, wherein...

[0007] The width of the flow stabilizer plate disposed on the first plate is half the width of the first plate.

[0008] The width of the current stabilizer plate disposed on the second plate is half the width of the second plate.

[0009] In one possible implementation, the flow stabilizer slopes from one side of the valve stem toward the side away from the valve stem.

[0010] In one possible implementation, the thickness of the flow stabilizer plate gradually decreases from both ends of the valve stem toward the middle.

[0011] In one possible implementation, the valve stem is arranged along the central axis of the butterfly plate body.

[0012] In one feasible implementation, the flow stabilizer is detachably connected to the butterfly plate body.

[0013] In one feasible implementation, the valve body is configured as a clamp-type valve body, and the valve body is provided with a plurality of bolt positioning holes, which are evenly distributed along the circumferential direction of the plate surface of the valve body.

[0014] Compared with the prior art, this disclosure includes at least the following beneficial effects:

[0015] The flow stabilizer plate disclosed herein is disposed on the side of the butterfly plate body connected to the valve stem, and the side of the flow stabilizer plate connected to the valve stem is flush with the top surface of the valve stem protruding from the butterfly plate body, so that the flowing medium cannot contact the valve stem along the flow direction. The flow stabilizer plate significantly reduces the negative pressure area of ​​the flowing medium in the valve stem area, and the negative pressure area is transferred from the valve stem to the butterfly plate and the pressure stabilizer plate, preventing air from continuously entering the equipment due to poor sealing performance of the valve stem, gradually accumulating, and causing a series of electrical faults. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0017] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of exemplary embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0019] Figure 1 This is a front view structural diagram of the present disclosure;

[0020] Figure 2 This is a schematic diagram of the butterfly plate assembly and valve stem disclosed herein.

[0021] in, Figures 1 to 2 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0022] 1-Valve body; 11-Bolt positioning hole; 2-Valve stem; 3-Butterfly plate assembly; 31-Butterfly plate body; 311-First plate; 312-Second plate; 32-Flow stabilizer plate. Detailed Implementation

[0023] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0024] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0025] In equipment requiring butterfly valves, such as transformers, the raised valve stem causes a sudden increase in oil velocity as the oil flows past it. According to Bernoulli's principle, higher velocity results in lower pressure, creating a negative pressure zone near the valve stem. If the valve stem seal is faulty, air can enter the transformer oil due to this negative pressure. This continuous influx of air into the transformer can lead to reduced insulation performance and transformer failure. Furthermore, air will gradually accumulate in the gas relay. When the gas level reaches a certain point, it will trigger a light gas alarm. If the cause of the light gas alarm is not addressed promptly, the gas may continue to accumulate, eventually triggering a heavy gas alarm, causing the transformer to trip and resulting in more severe equipment damage. Therefore, the negative pressure generated by the butterfly valve under high-speed oil flow can have serious consequences.

[0026] Based on this, the present disclosure provides a butterfly valve that reduces the negative pressure in the valve stem region. The flow stabilizing plate of the present disclosure is disposed on the side of the butterfly plate body connected to the valve stem, and the side of the flow stabilizing plate connected to the valve stem is flush with the top surface of the valve stem protruding from the butterfly plate body, so that the flowing medium cannot contact the valve stem along the flow direction. The flow stabilizing plate significantly reduces the negative pressure area of ​​the flowing medium in the valve stem region, and the negative pressure area is transferred from the valve stem to the butterfly plate and the pressure stabilizing plate, preventing air from continuously entering the transformer due to poor sealing performance of the valve stem, gradually accumulating in the gas relay, and causing a series of electrical faults.

[0027] The butterfly valve that reduces negative pressure in the valve stem region will be described in detail below through specific embodiments:

[0028] Reference Figures 1 to 2 As shown, a first aspect of this disclosure provides a butterfly valve for reducing negative pressure in the valve stem region, including a valve body 1, a valve stem 2, and a butterfly plate assembly 3. A valve cavity is formed within the valve body 1, and the valve stem 2 passes through the valve cavity radially. The butterfly plate assembly 3 is connected to the valve stem 2, and the valve stem 2 is used to drive the butterfly plate assembly 3 to close or open the valve cavity. The butterfly plate assembly 3 includes a butterfly plate body 31 and a flow stabilizing plate 32. The flow stabilizing plate 32 is disposed on the side of the butterfly plate body 31 connected to the valve stem 2, and the side of the flow stabilizing plate 32 connected to the valve stem 2 is flush with the top surface of the valve stem 2 protruding from the butterfly plate body 31. The flow stabilizing plate 32 is used to prevent the flowing medium from contacting the valve stem 2 along the flow direction.

[0029] In the operation of equipment, the butterfly valve controls the rotation angle of the butterfly plate body 31 by rotating the valve stem 2 through the action of a wrench. At a rotation of 90°, the flow rate of the medium through the valve chamber is at its maximum. According to Bernoulli's principle, the mechanical energy of an ideal fluid is conserved. For fluids of the same medium at the same height, the greater the flow velocity, the greater the kinetic energy and the smaller the pressure potential energy. Conversely, the smaller the flow velocity, the smaller the kinetic energy and the greater the pressure potential energy. When the butterfly plate rotates, the oil flow, passing the valve stem 2, protrudes from the butterfly plate body 31, causing a sudden increase in the oil flow velocity. This results in a sudden decrease in pressure near the valve stem 6, creating a negative pressure area. Based on the causes of the aforementioned problems, existing technologies can embed the valve stem 2 inside the butterfly plate body 31, preventing the oil from directly contacting the valve stem 2. However, this solution presents significant mechanical strength and sealing issues. For example, the valve stem 2 penetrating the butterfly plate body 31 inevitably creates an opening in the butterfly plate. The structure at this opening location is relatively weak and cannot meet the requirements of high-pressure applications such as transformers, leading to a substantial increase in the failure rate over long-term use. Secondly, the insertion of the valve stem 2 into the butterfly plate body 31 requires additional sealing components, making it difficult to guarantee a proper seal. Furthermore, if the butterfly plate body 31 and the valve stem 2 are integrally molded, the strength of the valve stem 2 is difficult to guarantee. If the valve stem 2 and the butterfly plate body 31 are not continuously aligned along the extension direction of the butterfly plate body 31, then breakage is likely to occur at the connection point between the valve stem 2 and the butterfly plate body 31.

[0030] This disclosure, while ensuring the structural strength of the valve stem 2 and the butterfly plate body 31, allows the flow stabilizer 32 to be either an independent structural component or an integrally formed component with the butterfly plate body 31. For example, the flow stabilizer 32 can be detachably connected to the butterfly plate body 31, serving as an independent structural component; or the flow stabilizer 32 can be welded to the butterfly plate body 31, or the butterfly plate body 31 and the flow stabilizer 32 can be integrally cast. In the integrally cast embodiment, if the fluid medium flows in a single direction, the flow stabilizer 32 is positioned on the fluid medium inlet side; if the fluid medium flows in both directions, two flow stabilizers 32 are provided, with the valve stem 2 mounted between them to ensure that both sides of the valve stem 2 are protected by the flow stabilizer 32, enabling the flow stabilizer 32 to function regardless of which side the material is introduced from. Specifically, the edge of the flow stabilizer 32 can adopt a streamlined design, such as an arc-shaped edge, which can transfer and disperse fluid pressure to both sides of the flow direction when in contact with the fluid medium, reducing the resistance of the flowing medium during flow. Furthermore, as the fluid medium flows, it passes through the flow stabilizer plate 32 and the valve stem 2 successively. Due to the flow stabilizer plate 32, a negative pressure area will no longer form near the valve stem 2; instead, the negative pressure area will be transferred from the vicinity of the valve stem 2 to the flow stabilizer plate 32 and the butterfly plate body 31. It should be noted that the size of the flow stabilizer plate 32, without affecting the normal opening and closing function of the butterfly valve, can be either fully covering the butterfly plate body 31 or partially covering it. In this disclosure, it is specifically set to partially cover the butterfly plate body 31, thereby ensuring the flow rate and velocity of the fluid medium when the butterfly valve is opened.

[0031] In some embodiments, the valve stem 2 defines the butterfly plate body 31 as a first plate 311 and a second plate 312, and the flow stabilizing plate 32 is respectively disposed on the first plate 311 and the second plate 312, wherein the width of the flow stabilizing plate 32 disposed on the first plate 311 is half the width of the first plate 311; and the width of the flow stabilizing plate 32 disposed on the second plate 312 is half the width of the second plate 312.

[0032] In this embodiment, the width of the flow stabilizer 32 disposed on the first plate 311 is half the width of the first plate 311; the width of the flow stabilizer 32 disposed on the second plate 312 is half the width of the second plate 312. The flow stabilizer 32 and the two plates of the butterfly plate body 31 form a stepped structure, so that the negative pressure zone generated by the fluid medium is concentrated on the flow stabilizer 32 and the butterfly plate body 31.

[0033] In some embodiments, the flow stabilizer 32 slopes down from one side of the valve stem 2 to the side away from the valve stem 2. In this embodiment, because the flow stabilizer 32 is designed with a gradually decreasing slope, that is, the lowest point of the flow stabilizer 32 drops to be flush with the butterfly plate body 31, the generated negative pressure also gradually decreases.

[0034] In some embodiments, the thickness of the flow stabilizer 32 gradually decreases from both ends of the valve stem 2 toward the middle.

[0035] In this embodiment, the thickness described in this disclosure refers to the surface facing the direction of fluid medium flow. When the fluid medium flows into contact with the flow stabilizer plate 32, if the thickness surface of the flow stabilizer plate 32 protrudes from the butterfly plate body 31, the flow stabilizer plate 32 will affect the flow velocity of the fluid medium to a certain extent. If the thickness surface of the flow stabilizer plate 32 is set to be flush with the butterfly plate body 31, the flow velocity of the fluid medium will increase, and the flow velocity and pressure of the fluid medium at that position will be unstable due to the shape of the flow stabilizer plate 32. However, the thickness of the flow stabilizer plate 32 of this disclosure gradually decreases from both ends of the valve stem 2 towards the middle, so that the fluid velocity is the fastest and the pressure potential energy is the lowest at the middle position of the flow stabilizer plate 32, while the flow velocity and pressure potential energy gradually increase from the middle to both ends, so that the overall flow velocity and pressure of the fluid medium tend to be stable when passing through the flow stabilizer plate 32.

[0036] In some embodiments, the valve stem 2 is arranged along the central axis of the butterfly plate body 31. In this embodiment, the valve stem 2 is arranged along the central axis of the butterfly plate body 31 to facilitate the opening and closing of the butterfly plate body 31.

[0037] In some embodiments, the valve body 1 is configured as a clamp-type valve body, and the valve body 1 is provided with a plurality of bolt positioning holes 11, which are evenly distributed along the circumferential direction of the plate surface of the valve body 1.

[0038] In this embodiment, the valve body 1 is configured as a clip-on valve body. The clip-on valve body has a compact structure, making it particularly suitable for environments with limited space or short pipe spacing, and also making installation and maintenance relatively convenient. Multiple bolt positioning holes 11 are used for pipe connections.

[0039] In this disclosure, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise expressly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0040] In the description of this disclosure, it should be understood that the terms "upper," "lower," "left," "right," "front," "rear," 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 this disclosure and simplifying the description, and do not indicate or imply that the device or unit 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 this disclosure.

[0041] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0042] The above are merely preferred embodiments of this disclosure and are not intended to limit this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A butterfly valve for reducing negative pressure in a valve stem area, characterized by, The valve includes a valve body, a valve stem and a butterfly plate assembly, the valve body has a valve cavity formed therein, the valve stem is arranged along a radial direction of the valve cavity, the butterfly plate assembly is connected to the valve stem, and the valve stem is used to drive the butterfly plate assembly to close or open the valve cavity. The butterfly plate assembly includes a butterfly plate body and a flow stabilizing plate, the flow stabilizing plate is arranged on a side of the butterfly plate body connected to the valve stem, a side of the flow stabilizing plate connected to the valve stem is flush with a top surface of the butterfly plate body protruding from the valve stem, and the flow stabilizing plate is used to prevent a flow medium from contacting the valve stem along a flow direction.

2. The butterfly valve of claim 1, wherein, The valve stem defines the butterfly plate body as a first plate body and a second plate body, and the flow stabilizing plate is arranged on the first plate body and the second plate body, respectively. The flow stabilizing plate arranged on the first plate body has a width of one half of a width of the first plate body. The flow stabilizing plate arranged on the second plate body has a width of one half of a width of the second plate body.

3. The butterfly valve of claim 1, wherein, The flow stabilizing plate slopes from a side of the valve stem to a side away from the valve stem.

4. The butterfly valve of claim 1, wherein, The flow stabilizing plate gradually decreases in thickness from both ends of the valve stem to a middle part.

5. The butterfly valve of claim 1, wherein, The valve stem is arranged along a central axis of the butterfly plate body.

6. The butterfly valve of claim 1, wherein, The flow stabilizing plate is detachably connected to the butterfly plate body.

7. The butterfly valve of any one of claims 1 to 6, wherein, The valve body is arranged as a clamping valve body, and a plurality of bolt positioning holes are arranged on the valve body and are uniformly distributed along a plate surface of the valve body.

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