Novel valve rod packing sealing structure and valve adopting same

Abstract

The utility model relates to the technical field of valves, in particular to a novel valve rod packing sealing structure and a valve with the novel valve rod packing sealing structure, the novel valve rod packing sealing structure comprises a gland, a packing pressing ring and a packing assembly, the gland is provided with a packing cavity, and the packing pressing ring and the packing assembly are arranged in the packing cavity from top to bottom. The packing assembly has elasticity, and the packing pressing ring is used for applying pressure to the packing assembly; the packing cavity comprises an inclined section, the inner wall of the inclined section is inclined, the inclined section corresponds to a packing assembly, the distance between the inner wall of the inclined section and the valve rod is d, and the distance d is gradually reduced in the direction from the packing assembly to the packing pressing ring. According to the novel valve rod packing sealing structure and the valve adopting the novel valve rod packing sealing structure, when medium pressure fluctuation or impact occurs in the valve body, frequent and violent pressure fluctuation repeatedly impacts the packing assembly, the packing assembly can make contact with the inner wall of the packing cavity and the valve rod more tightly, and then the sealing performance of the packing assembly is improved.

Description

Technical Field

[0001] This utility model relates to the field of valve technology, specifically to a novel valve stem packing sealing structure and a valve using this structure. Background Technology

[0002] A valve stem sealing structure typically refers to a sealing device between the valve body and the valve stem that prevents fluid leakage from the valve body through the gap between the valve stem and the valve body. The valve stem is a major component of the valve, and its sealing performance directly affects the valve's performance and lifespan.

[0003] Currently, when sealing valve stems, the commonly chosen sealing method is stuffing box sealing. Specifically, by compressing the packing, it causes radial expansion, thereby filling the gap between the valve body and the valve stem to achieve a seal. However, when there are pressure fluctuations or impacts in the valve body, such as frequent and severe pressure fluctuations repeatedly impacting the packing, the packing will move up and down within the packing cavity, causing the packing to rub against the inner wall of the packing cavity and the valve stem simultaneously. Since this friction is usually quite intense, it can easily lead to complete failure of the packing seal in a short period of time, resulting in serious leakage.

[0004] Therefore, how to improve the sealing performance of packing is a technical problem that urgently needs to be solved. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of current valve stem sealing structures in practical use by providing a novel valve stem packing sealing structure and a valve using this structure, thereby improving the sealing performance of the packing.

[0006] To achieve the above-mentioned objectives, this utility model provides the following technical solution:

[0007] A novel valve stem packing seal structure includes a gland, a packing ring, and a packing assembly. The gland is used to mate with the valve stem and has a packing cavity. The packing ring and the packing assembly are disposed in the packing cavity from top to bottom. The packing assembly is elastic. The packing ring applies pressure to the packing assembly so that the outer wall of the packing assembly fits against the inner wall of the packing cavity, and the inner wall of the packing assembly fits against the side wall of the valve stem, thereby sealing the gap between the gland and the valve stem.

[0008] The packing cavity includes an inclined section with an inclined inner wall. The inclined section corresponds to a packing assembly. The distance d between the inner wall of the inclined section and the valve stem gradually decreases in the direction from the packing assembly to the packing ring.

[0009] As a preferred technical solution of this application, the packing cavity further includes a vertical section, the inner wall of which is vertical, and a packing pressure ring is corresponding to the vertical section.

[0010] As the preferred technical solution of this application, the packing assembly includes a V-shaped upper pressure block, a V-shaped middle pressure block and a V-shaped lower pressure block, which are arranged sequentially from top to bottom;

[0011] The bottom cross-section of the upper V-shaped pressure block is a concave arc; the top cross-section of the middle V-shaped pressure block is a convex arc, and the bottom cross-section of the middle V-shaped pressure block is a concave arc; the top cross-section of the lower V-shaped pressure block is a convex arc.

[0012] As the preferred technical solution of this application, the V-shaped intermediate pressure block has several components.

[0013] As the preferred technical solution of this application, the curvature of the arc at the bottom cross-section of the upper V-shaped pressure block is greater than the curvature of the arc at the top cross-section of the middle V-shaped pressure block;

[0014] The curvature of the arc at the bottom cross-section of the V-shaped middle pressure block is greater than that at the top cross-section of the V-shaped middle pressure block;

[0015] The curvature of the arc at the bottom cross-section of the V-shaped middle pressure block is greater than that at the top cross-section of the V-shaped lower pressure block.

[0016] As a preferred technical solution of this application, a groove is provided on the inner wall of the packing cavity. The length direction of the groove is the same as the length direction of the gland. The groove is used to limit the packing assembly to constrain the rotation of the packing assembly relative to the packing cavity about the central axis of the packing cavity.

[0017] As the preferred technical solution of this application, the groove has a plurality of grooves, which are distributed around the central axis of the packing cavity.

[0018] As a preferred technical solution of this application, the packing assembly further includes a rectangular packing, which is ring-shaped and has a rectangular cross-section. The rectangular packing is located between the packing pressure ring and the V-shaped upper pressure block.

[0019] As the preferred technical solution of this application, the gland and the packing ring are detachably connected by a stud and nut structure;

[0020] The stud and nut structure can adjust the pressure applied by the packing pressure ring to the packing assembly.

[0021] This utility model also provides a valve, including a novel valve stem packing seal structure as described above.

[0022] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0023] 1. In the scheme of this application, the gland is part of the valve body. By setting an inclined section, the inner wall of the inclined section is inclined, and the distance d gradually decreases in the direction from the packing assembly to the packing ring. When the packing ring presses on the packing assembly, the inner wall of the packing assembly contacts the valve stem, and the outer wall of the packing assembly contacts the inner wall of the packing cavity. The packing assembly can be deformed under pressure, so that the cross-section of the packing assembly is trapezoidal with a narrow top and a wide bottom. In this way, when there are medium pressure fluctuations or impacts in the valve body, frequent and violent pressure fluctuations repeatedly impact the packing assembly. The pressure acts on the bottom of the packing assembly, which can make the packing assembly subject to pressure from bottom to top. With the inclined section, the packing assembly can contact the inner wall of the packing cavity and the valve stem more tightly, thereby improving the sealing performance of the packing assembly.

[0024] 2. By setting up V-shaped upper pressure block, V-shaped middle pressure block and V-shaped lower pressure block, the V-shaped upper pressure block, V-shaped middle pressure block and V-shaped lower pressure block are stacked and arranged. The V-shaped upper pressure block, V-shaped middle pressure block and V-shaped lower pressure block are collectively referred to as V-shaped pressure blocks. When the V-shaped pressure blocks are compressed, they can be deformed and extended along the width direction. This can further improve the tightness of the contact between the V-shaped pressure blocks and the inner wall of the packing cavity and the valve stem, thereby further improving the sealing performance of the packing assembly.

[0025] 3. By limiting the curvature of the V-shaped pressure block, the two adjacent V-shaped pressure blocks are not completely fitted together, and there is a gap between the two adjacent V-shaped pressure blocks. The existence of this gap is more conducive to the deformation of the V-shaped pressure block under pressure.

[0026] 4. By setting grooves on the inner wall of the packing cavity, the packing assembly can deform when the packing ring applies pressure to it, causing the grooves to be filled. This results in the outer wall of the packing assembly becoming non-circular, thus limiting the packing assembly's movement relative to the packing cavity. This increases the resistance to the packing assembly's rotation relative to the packing cavity, thereby constraining the rotation of the packing assembly relative to the central axis of the packing cavity. As a result, during valve stem rotation, the wear between the packing assembly and the inner wall of the packing cavity is reduced, thereby improving the service life of the packing assembly. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of one embodiment of a novel valve stem packing sealing structure according to this application;

[0028] Figure 2 This is a schematic diagram of the structure located at the packing assembly in one embodiment of a novel valve stem packing sealing structure according to this application;

[0029] Figure 3 This is a schematic diagram of the packing cavity in one embodiment of a novel valve stem packing sealing structure according to this application;

[0030] Figure 4 This is a schematic diagram of one embodiment of a valve according to this application;

[0031] The diagram shows: 1-Glander, 2-Packing ring, 3-Packing assembly, 4-Valve stem, 5-Packing cavity, 6-Inclined section, 7-Vertical section, 8-V-shaped upper pressure block, 9-V-shaped middle pressure block, 10-V-shaped lower pressure block, 11-Groove, 12-Rectangular packing, 13-Stud, 14-Nut. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model.

[0033] Therefore, the following detailed description of the embodiments of this utility model is not intended to limit the scope of the claimed utility model, but merely to illustrate some embodiments of the utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0034] It should be noted that, unless otherwise specified, the embodiments and features and technical solutions in the present invention can be combined with each other.

[0035] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0036] In the description of this utility model, it should be noted that the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use, or the orientation or positional relationship commonly understood by those skilled in the art. These terms are only for the convenience of describing this utility model and 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, and therefore should not be construed as a limitation on this utility model. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0037] Example 1: This example provides a novel valve stem packing seal structure, see [link to example]. Figures 1-3 As shown, the device includes a gland 1, a packing ring 2, and a packing assembly 3. The gland 1 is used to cooperate with the valve stem 4. The gland 1 is provided with a packing cavity 5. The packing ring 2 and the packing assembly 3 are arranged from top to bottom in the packing cavity 5. The packing assembly 3 is elastic. The packing ring 2 is used to apply pressure to the packing assembly 3 so that the outer wall of the packing assembly 3 fits against the inner wall of the packing cavity 5, and the inner wall of the packing assembly 3 fits against the side wall of the valve stem 4, so that the packing assembly 3 seals the gap between the gland 1 and the valve stem 4.

[0038] The packing cavity 5 includes an inclined section 6, the inner wall of which is inclined, and the inclined section 6 corresponds to the packing assembly 3. The distance d between the inner wall of the inclined section 6 and the valve stem 4 is d, and the distance d gradually decreases in the direction from the packing assembly 3 to the packing pressure ring 2.

[0039] In this application, the gland 1 is part of the valve body. By setting the inclined section 6, the inner wall of the inclined section 6 is inclined, and the distance d gradually decreases in the direction from the packing assembly 3 to the packing ring 2. When the packing ring 2 presses on the packing assembly 3, the inner wall of the packing assembly 3 contacts the valve stem 4, and the outer wall of the packing assembly 3 contacts the inner wall of the packing cavity 5. The packing assembly 3 can be deformed under pressure, so that the cross-section of the packing assembly 3 is trapezoidal with a narrow top and a wide bottom. In this way, when there are medium pressure fluctuations or impacts in the valve body, the frequent and violent pressure fluctuations repeatedly impact the packing assembly 3. The pressure acts on the bottom of the packing assembly 3, so that the packing assembly 3 is subjected to pressure from bottom to top. With the inclined section 6, the packing assembly 3 can contact the inner wall of the packing cavity 5 and the valve stem 4 more tightly, thereby improving the sealing performance of the packing assembly 3.

[0040] In a preferred embodiment, based on the above method, the packing cavity 5 further includes a vertical section 7, the inner wall of the vertical section 7 is vertical, and the vertical section 7 corresponds to the packing pressure ring 2.

[0041] Furthermore, by setting a vertical section 7, such that a packing pressure ring 2 is positioned corresponding to the vertical section 7, the stability of the packing pressure ring 2 within the packing cavity 5 can be improved after it is placed inside the packing cavity 5.

[0042] In a preferred embodiment, based on the above method, the packing assembly 3 further includes a V-shaped upper pressure block 8, a V-shaped middle pressure block 9, and a V-shaped lower pressure block 10, which are arranged sequentially from top to bottom.

[0043] The bottom cross-section of the upper V-shaped pressure block 8 is a concave arc shape; the top cross-section of the middle V-shaped pressure block 9 is a convex arc shape, and the bottom cross-section of the middle V-shaped pressure block 9 is a concave arc shape; the top cross-section of the lower V-shaped pressure block 10 is a convex arc shape.

[0044] Furthermore, by setting up an upper V-shaped pressure block 8, a middle V-shaped pressure block 9, and a lower V-shaped pressure block 10, the upper V-shaped pressure block 8, the middle V-shaped pressure block 9, and the lower V-shaped pressure block 10 are stacked together. The upper V-shaped pressure block 8, the middle V-shaped pressure block 9, and the lower V-shaped pressure block 10 are collectively referred to as V-shaped pressure blocks. When the V-shaped pressure blocks are compressed, they can be deformed and extended along the width direction. This can further improve the tightness of the contact between the V-shaped pressure blocks and the inner wall of the packing cavity 5 and the valve stem 4, thereby further improving the sealing performance of the packing assembly 3.

[0045] Furthermore, after being pressed, the V-shaped upper pressure block 8, V-shaped middle pressure block 9, or V-shaped lower pressure block 10 of this application can all reach the point where one side contacts the inner wall of the packing cavity 5 and the other side contacts the valve stem 4; and the V-shaped upper pressure block 8, V-shaped middle pressure block 9, or V-shaped lower pressure block 10 are all annular.

[0046] As a preferred embodiment, based on the above method, the V-shaped pressure block 9 further comprises a plurality of blocks.

[0047] Furthermore, by setting several V-shaped intermediate pressure blocks 9, it is convenient to configure different numbers of V-shaped intermediate pressure blocks 9 in the packing assembly 3, thereby changing the height of the packing assembly 3 and adapting the packing assembly 3 to packing cavities 5 of different heights, thereby improving the adaptability of the packing assembly 3.

[0048] As a preferred embodiment, based on the above method, the curvature of the arc at the bottom cross-section of the upper V-shaped pressure block 8 is greater than the curvature of the arc at the top cross-section of the middle V-shaped pressure block 9.

[0049] The curvature of the arc at the bottom cross-section of the V-shaped middle pressure block 9 is greater than that at the top cross-section of the V-shaped middle pressure block 9.

[0050] The curvature of the arc at the bottom cross-section of the V-shaped middle pressure block 9 is greater than that at the top cross-section of the V-shaped lower pressure block 10.

[0051] Furthermore, by limiting the curvature of the V-shaped pressure block, the two adjacent V-shaped pressure blocks are not completely fitted together, and there is a gap between the two adjacent V-shaped pressure blocks. The existence of this gap is more conducive to the deformation of the V-shaped pressure block under pressure. The V-shaped pressure block of this application can be a graphite filler.

[0052] Example 2: Based on the technical solution of Example 1, further details are provided below. Figures 1-3 As shown, a groove 11 is provided on the inner wall of the packing cavity 5. The length direction of the groove 11 is the same as the length direction of the gland 1. The groove 11 is used to limit the packing assembly 3 to constrain the rotation of the packing assembly 3 relative to the packing cavity 5 around the central axis of the packing cavity 5.

[0053] Furthermore, by providing a groove 11 on the inner wall of the packing cavity 5, the packing assembly 3 can deform when the packing pressure ring 2 applies pressure to the packing assembly 3, causing the groove 11 to be filled. This results in the outer wall of the packing assembly 3 becoming non-circular, thereby limiting the packing assembly 3 by the groove 11 and increasing the resistance to the rotation of the packing assembly 3 relative to the packing cavity 5. This constrains the rotation of the packing assembly 3 relative to the packing cavity 5 in the central axial direction, thereby reducing the wear between the packing assembly 3 and the inner wall of the packing cavity 5 during the rotation of the valve stem 4, and thus improving the service life of the packing assembly 3.

[0054] As a preferred embodiment, based on the above method, the groove 11 is further provided as a plurality of grooves, which are distributed around the central axis of the packing cavity 5.

[0055] Furthermore, by setting several grooves 11, the resistance of the packing assembly 3 to rotation relative to the packing cavity 5 can be further increased, thereby further reducing the wear between the packing assembly 3 and the inner wall of the packing cavity 5 during the rotation of the valve stem 4.

[0056] As a preferred embodiment, based on the above method, the packing assembly 3 further includes a rectangular packing 12, which is ring-shaped and has a rectangular cross-section. The rectangular packing 12 is located between the packing pressure ring 2 and the V-shaped upper pressure block 8.

[0057] Furthermore, by setting a rectangular packing 12, the rectangular packing 12 is located between the packing pressure ring 2 and the V-shaped upper pressure block 8. When the packing pressure ring 2 applies pressure to the rectangular packing 12, the rectangular packing 12 can fit against the valve stem 4 and the inner wall of the packing cavity 5. The rectangular packing 12 is an elastic graphite packing, which further improves the sealing performance of the packing assembly 3.

[0058] As a preferred embodiment, based on the above method, the gland 1 and the packing ring 2 are further detachably connected by a stud and nut structure;

[0059] The stud and nut structure can adjust the pressure applied by the packing pressure ring 2 to the packing assembly 3.

[0060] Furthermore, by setting a stud and nut structure, specifically, the stud 13 is set on the gland 1, and the packing ring 2 is provided with a through hole. The stud 13 passes through the through hole and then cooperates with the nut 14, thereby connecting the gland 1 and the packing ring 2. At the same time, by rotating the nut 14, the pressure applied by the packing ring 2 to the packing assembly 3 can be adjusted. In this way, when the packing assembly 3 experiences slight wear, the pressure can be increased to ensure the sealing performance of the packing assembly 3, thereby improving the stability of the sealing performance of the novel valve stem packing sealing structure of this application.

[0061] Example 3: This example provides a novel valve stem packing seal structure, see [link to example]. Figure 4 As shown, this includes a novel valve stem packing seal structure as described above.

[0062] The above embodiments are only used to illustrate the present utility model and are not intended to limit the technical solutions described in the present utility model. Although the present utility model has been described in detail with reference to the above embodiments, the present utility model is not limited to the specific embodiments described above. Therefore, any modifications or equivalent substitutions to the present utility model, and all technical solutions and improvements that do not depart from the spirit and scope of the utility model, are covered within the scope of the claims of the present utility model.

Claims

1. A novel valve stem packing seal structure, characterized in that: The device includes a gland, a packing ring, and a packing assembly. The gland is used to mate with a valve stem and has a packing cavity. The packing ring and the packing assembly are disposed in the packing cavity from top to bottom. The packing assembly is elastic. The packing ring applies pressure to the packing assembly so that the outer wall of the packing assembly fits against the inner wall of the packing cavity, and the inner wall of the packing assembly fits against the side wall of the valve stem, thereby sealing the gap between the gland and the valve stem. The packing cavity includes an inclined section with an inclined inner wall. The inclined section corresponds to a packing assembly. The distance d between the inner wall of the inclined section and the valve stem gradually decreases in the direction from the packing assembly to the packing ring.

2. The novel valve stem packing seal structure as described in claim 1, characterized in that: The packing cavity also includes a vertical section, the inner wall of which is vertical, and a packing pressure ring is corresponding to the vertical section.

3. The novel valve stem packing seal structure as described in claim 2, characterized in that: The packing assembly includes a V-shaped upper pressure block, a V-shaped middle pressure block, and a V-shaped lower pressure block, which are arranged sequentially from top to bottom. The bottom cross-section of the upper V-shaped pressure block is a concave arc; the top cross-section of the middle V-shaped pressure block is a convex arc, and the bottom cross-section of the middle V-shaped pressure block is a concave arc; the top cross-section of the lower V-shaped pressure block is a convex arc.

4. The novel valve stem packing seal structure as described in claim 3, characterized in that: The V-shaped pressure block has several components.

5. The novel valve stem packing seal structure as described in claim 4, characterized in that: The curvature of the arc at the bottom cross-section of the upper V-shaped pressure block is greater than that at the top cross-section of the middle V-shaped pressure block. The curvature of the arc at the bottom cross-section of the V-shaped middle pressure block is greater than that at the top cross-section of the V-shaped middle pressure block; The curvature of the arc at the bottom cross-section of the V-shaped middle pressure block is greater than that at the top cross-section of the V-shaped lower pressure block.

6. The novel valve stem packing seal structure as described in claim 5, characterized in that: A groove is provided on the inner wall of the packing cavity. The length direction of the groove is the same as the length direction of the gland. The groove is used to limit the packing assembly to constrain the rotation of the packing assembly relative to the packing cavity about the central axis of the packing cavity.

7. The novel valve stem packing seal structure as described in claim 6, characterized in that: The groove is of several kinds, and the grooves are distributed around the central axis of the packing cavity.

8. The novel valve stem packing seal structure as described in claim 7, characterized in that: The packing assembly also includes rectangular packing, which is ring-shaped and has a rectangular cross-section. The rectangular packing is located between the packing pressure ring and the V-shaped upper pressure block.

9. A novel valve stem packing seal structure as described in claim 8, characterized in that: The gland and the packing ring are detachably connected by a stud and nut structure. The stud and nut structure can adjust the pressure applied by the packing pressure ring to the packing assembly.

10. A valve, characterized in that: Including a novel valve stem packing seal structure as described in any one of claims 1-9.

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