Valve packing structure

Abstract

The utility model relates to a valve packing structure which comprises a valve cover provided with a cavity for containing a valve rod. The valve rod extends into the valve main body along the cavity; the sealing filler is arranged in the cavity; the sealing filler is arranged around the valve rod; the pressing assembly is arranged on the valve rod extending out of the valve cover in a sleeving manner; the pressing assembly is arranged on the side, away from the valve body, of the valve deck. The pressing assembly is connected with the valve cover; the heat insulation lining is arranged in the cavity; the heat insulation bush is arranged on the valve rod on the side, far away from the packing gland, of the sealing packing in a sleeving manner; and the pressing assembly is in contact with the sealing filler. The gap between the valve rod and the cavity is sealed through the heat insulation lining, contact between a medium in the valve and the sealing filler is effectively reduced, direct heat exchange between the medium and the sealing filler is avoided, and therefore the influence of the temperature of the medium on the temperature of the sealing filler is reduced, and fluctuation of the temperature of the sealing filler is effectively reduced.

Description

Technical Field

[0001] This utility model relates to the field of valve equipment technology, and in particular to valve packing structure. Background Technology

[0002] The sealing packing is the core component of the dynamic seal between the valve cover and the valve stem. It fills the tiny gap between the valve stem and the stuffing box through elastic deformation to prevent media leakage.

[0003] Temperature is a crucial parameter affecting the performance of sealing packings, as the temperature of the medium easily influences the temperature of the sealing packings. Excessively high temperatures reduce the elastic modulus of the sealing packings, causing them to lose their ability to deform within gaps. High temperatures can also damage the surface structure of some sealing packings; for example, the surface lubrication layer of graphite packings is destroyed in a high-temperature oxidizing environment, exacerbating wear between the sealing packings and the valve stem. Furthermore, the different coefficients of thermal expansion between the valve stem and the sealing packings mean that temperature changes can increase the gap between them. At low temperatures, packing freezing can lead to valve jamming and seal leakage.

[0004] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Utility Model Content

[0005] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a valve packing structure to reduce the temperature variation of the sealing packing.

[0006] The technical solution of this utility model is as follows:

[0007] The valve packing structure includes:

[0008] A valve cover has a cavity to accommodate a valve stem; the valve stem extends into the valve body along the cavity.

[0009] A sealing packing is disposed within the cavity; the sealing packing is arranged around the valve stem.

[0010] A clamping assembly is sleeved on the valve stem extending from the valve cover; the clamping assembly is located on the side of the valve cover away from the valve body; the clamping assembly is connected to the valve cover;

[0011] A heat-insulating bushing is disposed within the cavity; the heat-insulating bushing is fitted onto the valve stem on the side of the sealing packing away from the clamping assembly;

[0012] The clamping assembly contacts the sealing packing.

[0013] A further technical solution is that heat dissipation holes are provided on the valve cover; at least two heat dissipation holes are provided on the valve cover around the axis of the valve stem; and at least two heat dissipation holes are provided on the valve cover along the axis of the valve stem.

[0014] A further technical solution is that the heat dissipation holes on the valve stem are misaligned along the axis of the valve stem.

[0015] A further technical solution is that the closer to the sealing filler, the smaller the distance between the adjacent heat dissipation holes.

[0016] A further technical solution is that the clamping assembly includes a packing gland and a packing sleeve fitted on the valve stem; the packing gland is connected to the valve cover; the packing sleeve is disposed between the packing gland and the valve cover; and the packing sleeve extends into the cavity.

[0017] A further technical solution is that a first inclined surface is provided on the side of the packing gland close to the packing sleeve; a second inclined surface is provided on the packing sleeve to contact the first inclined surface; the first inclined surface is parallel to the second inclined surface; and the side of the first inclined surface away from the valve stem is close to the valve cover.

[0018] A further technical solution is that a first hole and a second hole are coaxially formed on the packing sleeve; the valve stem passes through the packing sleeve along the first hole and the second hole; the diameter of the second hole is larger than the diameter of the first hole; the second hole is located on the side of the first hole near the packing gland.

[0019] A further technical solution is that the packing sleeve is provided with an extension portion extending radially near the end of the packing gland.

[0020] A further technical solution is that the cavity also includes an expansion section with an enlarged inner diameter; a step is formed between the expansion section and the cavity without an enlarged inner diameter; the end of the heat insulation bushing away from the sealing packing contacts the step.

[0021] A further technical solution is that a first threaded hole is formed on the clamping assembly; a second threaded hole is formed on the valve cover; and a threaded connector is threadedly connected to the clamping assembly and the valve cover through the first threaded hole and the second threaded hole.

[0022] The beneficial technical effects of this utility model are as follows:

[0023] (1) The valve packing structure of this utility model includes a heat-insulating bushing fitted on the valve stem. The heat-insulating bushing seals the gap between the valve stem and the cavity, effectively reducing the contact between the medium inside the valve and the sealing packing, avoiding direct heat exchange between the medium and the sealing packing, thereby reducing the influence of the medium's temperature on the temperature of the sealing packing, and effectively reducing the temperature fluctuation of the sealing packing. The reduced temperature fluctuation of the sealing packing prevents temperature changes from affecting the elastic modulus, surface structure, and volume of the sealing packing, thus ensuring the normal operation of the sealing packing and guaranteeing its service life. In addition, the sealing packing and the clamping assembly cooperate to fix the position of the sealing packing, ensuring the stability of the entire valve packing structure.

[0024] (2) Furthermore, heat dissipation holes are provided on the valve stem. While hindering the heat transfer of the valve cover, the heat dissipation holes effectively increase the heat dissipation surface area of ​​the valve cover, further reducing the influence of the medium temperature on the temperature of the sealing packing.

[0025] (3) Further, the packing sleeve extends into the gap between the valve cover and the valve stem, restricting the position of the sealing packing while ensuring the sealing performance between the valve cover and the valve stem, and preventing leakage of the sealing packing. Attached Figure Description

[0026] Figure 1 A vertical cross-sectional view of a valve packing structure according to an embodiment of the present disclosure is shown when it is assembled on a valve.

[0027] Figure 2 A partially enlarged view of a valve packing structure according to an embodiment of the present disclosure is shown at point A.

[0028] Figure 3 A vertical cross-sectional schematic diagram of the packing gland and packing sleeve in a valve packing structure according to an embodiment of the present disclosure is shown.

[0029] Marked in the attached diagram:

[0030] 1. Valve body; 11. Valve cover; 111. Cavity; 112. Expansion section; 113. Step; 114. Second threaded hole; 12. Heat dissipation hole; 2. Sealing packing; 3. Insulating bushing; 4. Packing gland; 41. Threaded connector; 42. First inclined surface; 43. First threaded hole; 5. Packing sleeve; 51. First hole; 52. Second hole; 53. Second inclined surface; 54. Extension; 6. Valve stem. Detailed Implementation

[0031] To make the objectives, features, and advantages of this utility model more apparent and understandable, please refer to the accompanying drawings. It should be noted that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes and to aid those skilled in the art in understanding and reading the content disclosed herein. They are not intended to limit the implementation conditions of this utility model and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by this utility model, should still fall within the scope of the technical content disclosed in this utility model.

[0032] In the description of this utility model, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this utility model.

[0033] The valve packing structure includes a valve cover 11 with a cavity 111 to accommodate a valve stem 6. The valve stem 6 extends into the valve body 1 along the cavity 111. A sealing packing 2 is disposed within the cavity 111 and surrounds the valve stem 6. The sealing packing 2 seals the gap between the valve cover 11 and the valve stem 6, preventing leakage of the medium within the valve body 1. A clamping assembly is fitted onto the valve stem 6 extending from the valve cover 11. The clamping assembly is located on the side of the valve cover 11 away from the valve body 1. The clamping assembly connects to the valve cover 11 and contacts the sealing packing 2. The clamping assembly restricts the movement of the sealing packing 2 away from the valve body 1 and prevents leakage of the sealing packing 2 from the cavity 111. A heat-insulating bushing 3 is disposed within the cavity 111 and is fitted onto the valve stem 6 on the side of the sealing packing 2 away from the packing gland 4. The gap between the heat-insulating bushing 3, the sealing valve stem 6, and the cavity 111 effectively reduces the contact between the medium inside the valve and the sealing packing 2, avoiding direct heat exchange between the medium and the sealing packing 2. This reduces the impact of the medium's temperature on the temperature of the sealing packing 2, effectively reducing temperature fluctuations in the sealing packing 2. Reduced temperature fluctuations in the sealing packing 2 prevent temperature changes from affecting its elastic modulus, surface structure, and volume, thus ensuring the normal operation of the sealing packing 2 and guaranteeing its service life. Simultaneously, the sealing packing 2, in conjunction with the clamping assembly, fixes its position, ensuring the stability of the entire valve packing structure.

[0034] A heat dissipation hole 12 is provided on the valve cover 11. At least two heat dissipation holes 12 are provided on the valve cover 11 around the axis of the valve stem 6. At least two heat dissipation holes 12 are provided on the valve cover 11 along the axis of the valve stem 6. The heat dissipation holes 12 hinder the heat transfer of the valve cover 11 while effectively increasing the heat dissipation surface area of ​​the valve cover 11, further reducing the influence of the medium temperature on the temperature of the sealing packing 2.

[0035] Preferably, the heat dissipation holes 12 on the valve stem 6 are staggered along the axis of the valve stem 6. The staggered hole positions disperse stress and improve the structural strength of the valve cover 11.

[0036] More preferably, the closer to the sealing packing 2, the smaller the spacing between adjacent heat dissipation holes 12, so as to increase the density of the heat dissipation holes 12, that is, the closer to the sealing packing 2, the better the heat dissipation effect of the valve cover 11. This arrangement reduces the number of heat dissipation holes 12 in non-critical areas and saves processing costs.

[0037] The clamping assembly includes a packing gland 4 and a packing sleeve 5 fitted onto the valve stem 6. The packing gland 4 is connected to the valve cover 11. The packing sleeve 5 is positioned between the packing gland 4 and the valve cover 11. The packing sleeve 5 extends into the cavity 111. The packing sleeve 5 extends into the gap between the valve cover 11 and the valve stem 6, restricting the position of the sealing packing 2 while ensuring the sealing performance between the valve cover 11 and the valve stem 6, preventing leakage of the sealing packing 2.

[0038] In this embodiment, the packing gland 4 and the packing sleeve 5 are two independent components. In other embodiments, the packing gland 4 and the packing sleeve 5 may also be two parts of an integral, independent component.

[0039] Preferably, a first inclined surface 42 is provided on the side of the packing gland 4 near the packing sleeve 5. A second inclined surface 53 is provided on the packing sleeve 5 to contact the first inclined surface 42. The first inclined surface 42 and the second inclined surface 53 are parallel. The side of the first inclined surface 42 away from the valve stem 6 is close to the valve cover 11. When the packing gland 4 presses the packing sleeve 5 against the valve cover 11, the first inclined surface 42 and the second inclined surface 53 interact, converting the axial force of the packing gland 4 along the valve stem 6 into a radial force along the valve stem 6, thereby balancing the radial force applied by the valve stem 6 and improving the assembly stability of the packing sleeve 5.

[0040] More preferably, a first hole 51 and a second hole 52 are coaxially formed on the packing sleeve 5. The valve stem 6 passes through the packing sleeve 5 along the first hole 51 and the second hole 52. The diameter of the second hole 52 is larger than the diameter of the first hole 51. The second hole 52 is located on the side of the first hole 51 near the packing gland 4. At the location of the second hole 52, the gap between the packing sleeve 5 and the valve stem 6 is enlarged, reducing the contact area between the packing sleeve 5 and the valve stem 6, and reducing the friction between the packing sleeve 5 and the valve stem 6.

[0041] In some embodiments, the packing sleeve 5 is provided with an extension 54 extending radially near the end of the packing gland 4. A second inclined surface 53 is provided on the extension 54. The extension 54 increases the contact area between the packing gland 4 and the packing sleeve 5, reduces local pressure concentration, and facilitates the packing gland 4 to press the packing sleeve 5 tightly.

[0042] The cavity 111 also includes an expansion section 112 with an enlarged inner diameter. A step 113 is formed between the expansion section 112 and the cavity 111, which has no enlarged inner diameter. The end of the heat insulation bushing 3 away from the sealing packing 2 contacts the step 113. The step 113 abuts against the heat insulation bushing 3, restricting the position of the heat insulation bushing 3.

[0043] In some embodiments, a first threaded hole 43 is provided on the clamping assembly. A second threaded hole 114 is provided on the valve cover 11. The threaded connector 41 connects the clamping assembly and the valve cover 11 by means of the first threaded hole 43 and the second threaded hole 114. The threaded connection is easy to install and disassemble, convenient for maintenance, and has excellent tensile and shear resistance, and can withstand large loads. The threaded connector 41 can be a bolt, stud, screw, etc.

[0044] Preferably, at least two of the first threaded hole 43 and the second threaded hole 114 are evenly arranged around the valve stem 6.

[0045] The specific workflow of this utility model is as follows:

[0046] When the valve is in operation, the heat of the medium inside the valve body 1 is directly transferred to the sealing packing 2 or indirectly along the valve cover 11. The heat insulation bushing 3 fills the gap between the valve cover 11 and the valve stem 6, restricting direct contact between the medium inside the valve body 1 and the sealing packing 2. When the heat of the medium is transferred along the valve cover 11, the heat dissipation holes 12 impede this heat transfer and increase the surface area of ​​the valve cover 11, enhancing its heat dissipation performance. This reduces the influence of the medium's temperature on the temperature of the sealing packing 2.

[0047] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0048] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A valve packing structure, characterized in that, The valve packing structure includes: A valve cover has a cavity to accommodate a valve stem; the valve stem extends into the valve body along the cavity; A sealing packing is disposed within the cavity; the sealing packing is arranged around the valve stem. A clamping assembly is sleeved on the valve stem extending from the valve cover; the clamping assembly is located on the side of the valve cover away from the valve body; the clamping assembly is connected to the valve cover; A heat-insulating bushing is disposed within the cavity; the heat-insulating bushing is fitted onto the valve stem on the side of the sealing packing away from the clamping assembly; The clamping assembly contacts the sealing packing.

2. The valve packing structure as described in claim 1, characterized in that: The valve cover has heat dissipation holes; around the axis of the valve stem, the valve cover has at least two heat dissipation holes; along the axis of the valve stem, the valve cover has at least two heat dissipation holes.

3. The valve packing structure as described in claim 2, characterized in that: The heat dissipation holes on the valve stem are misaligned along the axis of the valve stem.

4. The valve packing structure as described in claim 2, characterized in that: The closer to the sealing filler, the smaller the distance between the adjacent heat dissipation holes.

5. The valve packing structure as described in claim 1, characterized in that: The clamping assembly includes a packing gland and a packing sleeve fitted on the valve stem; the packing gland is connected to the valve cover; the packing sleeve is disposed between the packing gland and the valve cover; the packing sleeve extends into the cavity.

6. The valve packing structure as described in claim 5, characterized in that: The packing gland has a first inclined surface on the side near the packing sleeve; the packing sleeve has a second inclined surface that contacts the first inclined surface; the first inclined surface is parallel to the second inclined surface; the side of the first inclined surface away from the valve stem is close to the valve cover.

7. The valve packing structure as described in claim 5, characterized in that: The packing sleeve has a first hole and a second hole coaxially formed; the valve stem passes through the packing sleeve along the first hole and the second hole; the diameter of the second hole is larger than the diameter of the first hole; the second hole is located on the side of the first hole near the packing gland.

8. The valve packing structure as described in claim 5, characterized in that: The packing sleeve is provided with an extension portion extending radially from the end near the end of the packing gland.

9. The valve packing structure as described in claim 1, characterized in that: The cavity also includes an expansion section with an enlarged inner diameter; a step is formed between the expansion section and the cavity without an enlarged inner diameter; the end of the heat insulation bushing away from the sealing packing contacts the step.

10. The valve packing structure as described in claim 1, characterized in that: The clamping assembly has a first threaded hole; the valve cover has a second threaded hole; the threaded connector connects the clamping assembly and the valve cover through the first threaded hole and the second threaded hole.

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