Butterfly valve shaft sealing structure

Abstract

The utility model is suitable for valve sealing technical field provides a butterfly valve valve shaft sealing structure, including valve body, the valve shaft body is rotationally arranged in the valve body inside, the surface of valve shaft body is provided with the packing gland that slides, it is provided in the flexible sealing cover of valve body inner wall lower extreme, the inside of flexible sealing cover is equipped with the cavity, the through -hole that penetrates flexible sealing cover outside is equipped with in the cavity inner bottom wall equidistance, the valve body inner wall fixedly connected with copper alloy support of flexible sealing cover top end, the valve body inner wall of copper alloy support top is provided with the packing ring, the top of packing ring is provided with graphite packing. The butterfly valve valve shaft sealing structure provided by the scheme utilizes the flexible sealing cover that can expand, makes the flexible sealing cover when medium leak will expand further improve the sealing, utilizes the oil pressure sealing of copper alloy support again, utilizes graphite packing and seal ring further physical sealing simultaneously, and then passes through three -fold sealing, great improvement its sealing effect.

Description

Technical Field

[0001] This utility model belongs to the field of valve sealing technology, and in particular relates to a butterfly valve shaft sealing structure. Background Technology

[0002] A butterfly valve is a type of valve that controls the flow of fluid or regulates its flow rate by rotating a disc-shaped butterfly plate around its axis. It can be used for the on / off control of low-pressure pipeline media. The valve shaft is the core transmission component of the butterfly valve, and its sealing performance directly affects the valve's working efficiency and service life.

[0003] Chinese patent CN214500219U discloses a sealing structure for a butterfly valve shaft. The paper states that it "comprises a valve body and a valve shaft. The lower end of the valve shaft is connected to a valve plate inside the valve body, and the upper end of the valve shaft extends from the shaft hole of the valve body and is connected to a drive mechanism. A packing seal and a hydraulic seal are provided between the upper end of the valve shaft and the shaft hole of the valve body. This sealing structure, combining packing and hydraulic seals, overcomes the leakage defects between the valve shaft and valve body in existing technologies. Combined with the use of graphite packing, it achieves easy valve opening and closing, good sealing performance, and high reliability. Furthermore, the overall structure is scientifically sound, simple, and compact, making installation and use convenient, resulting in significant economic and social benefits. It is widely applicable for use in pipeline media interception."

[0004] However, the above solution does not have multiple seals, which may lead to leakage during use. At the same time, the large opening and closing torque makes it difficult for the valve shaft to rotate smoothly. Therefore, it is necessary to design a butterfly valve shaft sealing structure. Utility Model Content

[0005] This utility model provides a butterfly valve shaft sealing structure, which aims to solve the problem that some currently used sealing structures are inconvenient for multiple sealing.

[0006] This utility model is implemented as follows: a butterfly valve shaft sealing structure includes a valve body; a valve shaft body rotatably disposed inside the valve body, a packing gland slidably sleeved on the surface of the valve shaft body, the packing gland being fixedly connected to the top of the valve body by bolts; a flexible sealing sleeve disposed at the lower end of the inner wall of the valve body, the flexible sealing sleeve having a cavity inside, through holes penetrating the outside of the flexible sealing sleeve being equally spaced on the bottom wall of the cavity, a copper alloy bracket fixedly connected to the inner wall of the valve body at the top of the flexible sealing sleeve, a packing ring disposed on the inner wall of the valve body above the copper alloy bracket, and graphite packing disposed at the top of the packing ring.

[0007] Preferably, the two sides of the bottom wall of the cavity are inclined, and the top end of the flexible sealing sleeve is in close contact with the bottom end of the copper alloy bracket.

[0008] Preferably, the inner wall of the copper alloy bracket is fixedly connected with sealing rings at equal intervals, and the sealing rings are O-shaped.

[0009] Preferably, the upper and lower ends of the inner wall of the copper alloy bracket are provided with spiral oil grooves, which are distributed in a spiral shape.

[0010] Preferably, the bottom end of the packing gland extends into the interior of the valve body, and the top end of the graphite packing is pressed and fixed by the bottom end of the packing gland.

[0011] Preferably, an oil injection nozzle is fixedly connected to the upper end of one side of the valve body, and an oil injection groove is opened on one side of the interior of the valve body. One end of the oil injection groove is connected to the upper end and the lower end of the interior of the copper alloy bracket, respectively, and the other end of the oil injection groove is connected to one end of the oil injection nozzle.

[0012] Preferably, a reserved groove is provided on one side of the oil injection nozzle, and an internal thread is provided inside the oil injection nozzle on the inner wall of the reserved groove. A threaded sealing plug that is threadedly connected to the reserved groove is threadedly engaged with the internal thread.

[0013] Preferably, friction plates are fixedly connected to the inner wall of the reserved groove at equal angles, and the friction plates are arc-shaped.

[0014] Compared with related technologies, the butterfly valve shaft sealing structure provided by this utility model has the following beneficial effects: The flexible sealing sleeve effectively blocks media leakage. Simultaneously, as the media pressure increases, some media enters the cavity through the through-hole, causing the flexible sealing sleeve to expand further and adhere tightly to the valve shaft body and the inner wall of the valve body, improving the sealing effect and achieving an adaptive seal. Furthermore, the spiral oil groove allows the injected lubricant to form a stable oil film, serving both lubrication and forming a liquid sealing barrier. An O-ring seal further enhances the sealing effect. The graphite packing and packing rings provide auxiliary sealing; the graphite packing is self-lubricating, heat-resistant, and has a low coefficient of friction, effectively reducing the rotational resistance of the valve shaft body. Thus, the flexible sealing sleeve effectively blocks media leakage, while the graphite packing, packing rings, and sealing rings form a second line of defense. The lubricant injection system inside the copper alloy bracket creates a liquid seal, achieving triple sealing protection and significantly improving the sealing effect and effectiveness. Attached Figure Description

[0015] Figure 1 This is a frontal cross-sectional view of the present invention. Figure 2 This is a front view of the exploded structure of this utility model; Figure 3 This is a front view structural diagram of the present utility model; Figure 4This is a magnified structural diagram of the present invention viewed from below; Figure 5 This is an exploded magnified structural diagram of the oil nozzle of this utility model; Figure 6 For the present utility model Figure 1 Enlarged structural diagram at point A in the middle.

[0016] In the diagram: 1. Valve shaft body; 2. Packing gland; 3. Oil injection nozzle; 4. Valve body; 5. Copper alloy bracket; 6. Graphite packing; 7. Spiral oil groove; 8. Packing ring; 9. Sealing ring; 10. Flexible sealing sleeve; 11. Internal thread; 12. Threaded sealing plug; 13. Friction plate; 14. Reserved groove; 15. Oil injection groove; 16. Through hole; 17. Cavity. Detailed Implementation

[0017] 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 application belongs; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, not to describe a particular order.

[0018] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0019] Example 1 A preferred embodiment of the butterfly valve shaft sealing structure provided by this utility model is, for example... Figures 1 to 6 As shown: A butterfly valve shaft sealing structure includes a valve body 4; a valve shaft body 1 rotatably disposed inside the valve body 4, a packing gland 2 slidably sleeved on the surface of the valve shaft body 1, the packing gland 2 being fixedly connected to the top of the valve body 4 by bolts; a flexible sealing sleeve 10 disposed at the lower end of the inner wall of the valve body 4, the flexible sealing sleeve 10 having a cavity 17 inside, through holes 16 being equally spaced on the bottom wall of the cavity 17 penetrating the outside of the flexible sealing sleeve 10, a copper alloy bracket 5 being fixedly connected to the inner wall of the valve body 4 at the top of the flexible sealing sleeve 10, a packing ring 8 being disposed on the inner wall of the valve body 4 above the copper alloy bracket 5, and a graphite packing 6 being disposed at the top of the packing ring 8.

[0020] It should be noted that some existing butterfly valve shaft sealing structures still have certain shortcomings in actual use. They do not have multiple seals, which makes leakage possible during use. At the same time, the opening and closing torque is large, which makes it difficult for the valve shaft to rotate smoothly.

[0021] In a further preferred embodiment of this utility model, the two sides of the bottom wall of the cavity 17 are inclined, and the top of the flexible sealing sleeve 10 is in close contact with the bottom of the copper alloy bracket 5.

[0022] In this embodiment, the cavity 17 with its inclined inner bottom wall facilitates a more thorough and rapid discharge of the medium that enters the cavity 17.

[0023] In a further preferred embodiment of this utility model, sealing rings 9 are fixedly connected at equal intervals to the inner wall of the copper alloy bracket 5, and the sealing rings 9 are O-shaped.

[0024] In this embodiment, the sealing performance between the inner wall of the copper alloy bracket 5 and the surface of the valve shaft body 1 is further improved by using the O-ring seal 9.

[0025] In a further preferred embodiment of this utility model, spiral oil grooves 7 are provided at the upper and lower ends of the inner wall of the copper alloy bracket 5, and the spiral oil grooves 7 are distributed in a spiral shape.

[0026] In this embodiment, the lubricant inside the spiral oil groove 7 is used to form a stable oil film, which serves both as a lubricant and as a liquid-sealed barrier.

[0027] In a further preferred embodiment of the present invention, the bottom end of the packing gland 2 extends into the interior of the valve body 4, and the top end of the graphite packing 6 is pressed and fixed by the bottom end of the packing gland 2.

[0028] Example 2 Based on Embodiment 1, a preferred embodiment of the butterfly valve shaft sealing structure provided by this utility model is, for example... Figures 1 to 6 As shown: An oil injection nozzle 3 is fixedly connected to the upper end of one side of the valve body 4. An oil injection groove 15 is opened on one side inside the valve body 4. One end of the oil injection groove 15 is connected to the upper end and the lower end of the copper alloy bracket 5 respectively, and the other end of the oil injection groove 15 is connected to one end of the oil injection nozzle 3.

[0029] In this embodiment, the lubricant is conveniently injected into the gap between the surface of the valve shaft body 1 and the inner wall of the copper alloy bracket 5 through the oil injection nozzle 3 and the oil injection groove 15.

[0030] In a further preferred embodiment of the present invention, a reserved groove 14 is provided on one side of the oil nozzle 3, and an internal thread 11 is provided inside the oil nozzle 3 on the inner wall of the reserved groove 14. A threaded sealing plug 12 that is threadedly connected to the reserved groove 14 and is threadedly engaged with the internal thread 11 is provided inside the reserved groove 14.

[0031] In this embodiment, the threaded engagement between the threaded sealing plug 12 and the internal thread 11 is used to realize the disassembly and assembly of the threaded sealing plug 12 and the oil injection nozzle 3, so that the oil injection nozzle 3 can be completely blocked and sealed after the threaded sealing plug 12 is tightened.

[0032] In a further preferred embodiment of the present invention, a friction plate 13 is fixedly connected to the inner wall of the reserved groove 14 at equal angles, and the friction plate 13 is arc-shaped.

[0033] In this embodiment, the arc-shaped friction plate 13 is used to increase the friction between the nut of the threaded sealing plug 12 and the inner wall of the reserved groove 14, so as to avoid the threaded sealing plug 12 from accidentally loosening and causing the oil nozzle 3 to become blocked and the sealing performance to decrease.

[0034] In summary, the threaded sealing plug 12 can be loosened by using a screwdriver or other tools to open the oil injection nozzle 3. Then, the lubricant can be injected between the copper alloy bracket 5 and the valve shaft body 1 through the oil injection nozzle 3 and the oil injection groove 15. Finally, the threaded sealing plug 12 can be screwed into the oil injection nozzle 3 to achieve the sealing of the oil injection nozzle 3. At the same time, the flexible sealing sleeve 10 is used to block the leakage of the medium. When the medium pressure increases, some medium will enter the cavity 17 through the through hole 16, which will cause the flexible sealing sleeve 10 to expand further and fit tightly against the inner wall of the valve shaft body 1 and the valve body 4, thereby improving its sealing effect. In addition, the spiral oil groove 7 is used to allow the injected lubricant to form a stable oil film, which not only plays a lubricating role, but also forms a liquid sealing barrier. Furthermore, the O-ring seal 9 is set to provide a second sealing function, and the graphite packing 6 and packing ring 8 can provide auxiliary sealing. At the same time, the graphite packing 6 has self-lubricating and high temperature resistance, and a low coefficient of friction, which can effectively reduce the rotational resistance of the valve shaft body 1.

[0035] It is worth noting that the circuits, electronic components, and modules involved in this utility model are all existing technologies, which can be fully implemented by those skilled in the art, and need not be elaborated upon. The content protected by this utility model does not involve any improvement to the software and methods.

[0036] It should be understood that the disclosed apparatus can be implemented in other ways, given the several embodiments provided in this application. For example, the apparatus embodiments described above are merely illustrative; the division of units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or communication connections shown or discussed may be through some interfaces; the indirect coupling or communication connections between devices or units may be telecommunications or other forms.

[0037] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit the scope of protection of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on these embodiments, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Although this utility model has been described in detail with reference to the above embodiments, those skilled in the art can still combine, add, delete, or otherwise adjust the features of the various embodiments of this utility model according to the circumstances without conflict or creative effort, thereby obtaining different technical solutions that do not fundamentally depart from the concept of this utility model. These technical solutions are also within the scope of protection of this utility model.

Claims

1. A butterfly valve shaft sealing structure, characterized in that, include: Valve body (4); The valve shaft body (1) is rotatably disposed inside the valve body (4). A packing gland (2) is slidably sleeved on the surface of the valve shaft body (1). The packing gland (2) is fixedly connected to the top of the valve body (4) by bolts. A flexible sealing sleeve (10) is provided at the lower end of the inner wall of the valve body (4). A cavity (17) is provided inside the flexible sealing sleeve (10). Through holes (16) penetrating the outside of the flexible sealing sleeve (10) are provided at equal intervals on the bottom wall of the cavity (17). A copper alloy bracket (5) is fixedly connected to the inner wall of the valve body (4) at the top of the flexible sealing sleeve (10). A packing ring (8) is provided on the inner wall of the valve body (4) above the copper alloy bracket (5). Graphite packing (6) is provided at the top of the packing ring (8).

2. The butterfly valve shaft sealing structure as described in claim 1, characterized in that, The two sides of the bottom wall of the cavity (17) are inclined, and the top of the flexible sealing sleeve (10) is in close contact with the bottom of the copper alloy bracket (5).

3. The butterfly valve shaft sealing structure as described in claim 1, characterized in that, The inner wall of the copper alloy bracket (5) is fixedly connected with sealing rings (9) at equal intervals, and the sealing rings (9) are O-shaped.

4. The butterfly valve shaft sealing structure as described in claim 1, characterized in that, The upper and lower ends of the inner wall of the copper alloy bracket (5) are provided with spiral oil grooves (7), which are distributed in a spiral shape.

5. The butterfly valve shaft sealing structure as described in claim 1, characterized in that, The bottom end of the packing gland (2) extends into the interior of the valve body (4), and the top end of the graphite packing (6) is pressed and fixed by the bottom end of the packing gland (2).

6. The butterfly valve shaft sealing structure as described in claim 1, characterized in that, An oil injection nozzle (3) is fixedly connected to the upper end of one side of the valve body (4). An oil injection groove (15) is opened on one side inside the valve body (4). One end of the oil injection groove (15) is connected to the upper end and the lower end of the copper alloy bracket (5) respectively. The other end of the oil injection groove (15) is connected to one end of the oil injection nozzle (3).

7. The butterfly valve shaft sealing structure as described in claim 6, characterized in that, A reserved groove (14) is provided on one side of the oil injection nozzle (3). An internal thread (11) is provided inside the oil injection nozzle (3) on the inner wall of the reserved groove (14). A threaded sealing plug (12) that is threadedly connected to the reserved groove (14) is threadedly engaged with the internal thread (11).

8. The butterfly valve shaft sealing structure as described in claim 7, characterized in that, The inner wall of the reserved groove (14) is fixedly connected with a friction plate (13) at equal angles, and the friction plate (13) is arc-shaped.

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