A reinforced seal structure for a stopcock valve stem

Abstract

The utility model discloses a kind of reinforcing sealing structure for cock valve stem, including pressure ring, inner sealing ring, outer sealing ring, pressure disc and jacking bolt, inner cavity is formed between valve stem and bonnet, pressure ring, inner sealing ring, outer sealing ring and pressure disc are set on valve stem, and are placed in inner cavity;Jacking bolt is set on bonnet and acts on pressure disc, the upper surface of pressure ring is provided with convex part, first slope and second slope are set between pressure ring and convex part, outer sealing ring and inner sealing ring are respectively set in first sealing cavity and second sealing cavity, outer sealing ring is provided with the third slope matched with first slope, inner sealing ring is provided with the fourth slope matched with second slope. By setting inner sealing ring and outer sealing ring, and setting slope in the connecting portion of pressure ring and convex part, the downward jacking force of jacking screw is partially converted into radial force by slope cooperation, so that first sealing surface and second sealing surface are tightly attached, and sealing performance is improved.

Description

Technical Field

[0001] This utility model relates to the field of plug valves, and in particular to an enhanced sealing structure for the valve stem of a plug valve. Background Technology

[0002] There is a space between the valve stem and the inner cavity of the valve cover. A pressure ring, packing, and pressure disc are installed in this space. The sealing pressure comes from an external force pressing down on the pressure disc, which in turn squeezes the packing downwards. The packing deforms under this pressure, thus generating radial pressure on the sealing surface. However, the radial pressure generated by this method is limited because the lower end of the pressure ring is not a solid, rigid surface, but rather a stopcock and valve gasket. Therefore, it is impossible to press the packing with excessive force, as this would cause the stopcock to be pushed down and displaced, resulting in insufficient sealing pressure on the sealing surface and thus a relatively limited sealing effect. Utility Model Content

[0003] To address the shortcomings of existing technologies, the main objective of this utility model is to overcome these deficiencies by disclosing an enhanced sealing structure for a plug valve stem. The structure includes a pressure ring, an inner sealing ring, an outer sealing ring, a pressure plate, and a tightening bolt. An inner cavity is formed between the valve stem and the valve cover. The pressure ring, the inner sealing ring, the outer sealing ring, and the pressure plate are fitted onto the valve stem and placed within the inner cavity. The tightening bolt is mounted on the valve cover and acts on the pressure plate. A protrusion is provided on the upper surface of the pressure ring, dividing the inner cavity into a first sealing cavity and a second sealing cavity. A first inclined surface and a second inclined surface are provided between the pressure ring and the protrusion. The outer sealing ring and the inner sealing ring are respectively disposed within the first sealing cavity and the second sealing cavity. The outer sealing ring has a third inclined surface that mates with the first inclined surface, and the inner sealing ring has a fourth inclined surface that mates with the second inclined surface.

[0004] Furthermore, the angle between the first inclined surface, the second inclined surface and the upper surface of the pressure ring is 30°-75°.

[0005] Furthermore, the surface of the pressure plate is provided with a protruding extrusion part, and a clearance groove is formed between the extrusion parts, the size of which is smaller than the protrusion part.

[0006] Furthermore, the upper surface dimensions of the outer sealing ring and the inner sealing ring are larger than the dimensions of the extrusion portion.

[0007] Furthermore, the outer sealing ring and the inner sealing ring are made of PTFE.

[0008] Furthermore, at least two tightening bolts are provided, and they are distributed circumferentially around the valve stem.

[0009] The beneficial effects achieved by this utility model are as follows:

[0010] This invention features an inner sealing ring and an outer sealing ring, and an inclined surface at the connection between the pressure ring and the protrusion. Through the engagement of the inclined surface, the downward tightening force of the tightening screw is converted into a radial force, which makes the first sealing surface and the second sealing surface fit tightly together, thereby improving the sealing performance. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the appearance of a reinforced sealing component structure for a plug valve stem and the plug valve after assembly, according to the present invention.

[0012] Figure 2 This is a schematic diagram of the reinforced sealing component structure for the valve stem of a plug valve according to the present invention and the internal structure of the plug valve after assembly.

[0013] Figure 3 for Figure 2 Enlarged view of A in the middle;

[0014] Figure 4 for Figure 2 A schematic diagram of the structure without the inner and outer sealing rings assembled.

[0015] Figure 5 This is a schematic diagram of the outer sealing ring.

[0016] Figure 6 This is a schematic diagram of the inner sealing ring.

[0017] Figure 7 This is a schematic diagram of the pressure ring structure;

[0018] The attached figures are labeled as follows:

[0019] 1. Pressure ring, 2. Inner sealing ring, 3. Outer sealing ring, 4. Pressure plate, 5. Tightening bolt, 6. Valve stem, 7. Valve cover, 1. Protrusion, 12. First sealing cavity, 13. Second sealing cavity, 14. First inclined surface, 15. Second inclined surface, 21. Fourth inclined surface, 31. Third inclined surface, 41. Extrusion part, 42. Clearance groove. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0021] An enhanced sealing structure for the stem of a plug valve, such as Figures 1-7As shown, the valve includes a pressure ring 1, an inner sealing ring 2, an outer sealing ring 3, a pressure plate 4, and a tightening bolt 5. An inner cavity is formed between the valve stem 6 and the valve cover 7. The pressure ring 1, inner sealing ring 2, outer sealing ring 3, and pressure plate 4 are sleeved on the valve stem 6 and placed inside the inner cavity. The tightening bolt 5 is set on the valve cover 7 and acts on the pressure plate 4. A protrusion 11 is provided on the upper surface of the pressure ring 1, which divides the inner cavity into a first sealing cavity 12 and a second sealing cavity 13. A first inclined surface 14 and a second inclined surface 15 are provided between the pressure ring 1 and the protrusion 11. The outer sealing ring 3 and the inner sealing ring 2 are respectively set in the first sealing cavity 12 and the second sealing cavity 13. The outer sealing ring 3 is provided with a third inclined surface 31 that cooperates with the first inclined surface 14, and the inner sealing ring 2 is provided with a fourth inclined surface 21 that cooperates with the second inclined surface 15. The inner ring of the inner sealing ring 2 forms a first sealing surface with the valve stem 6. The second inclined surface 15 and the fourth inclined surface 21 cooperate. When the tightening bolt 5 drives the pressure plate 4 to press down, the force acting on the inner sealing ring 2 will decompose part of the radial force, making the inner sealing ring 2 tightly adhere to the valve stem 6, thus achieving the first sealing surface seal. Similarly, the outer ring of the outer sealing ring 3 forms a second sealing surface with the valve cover 7. The first inclined surface 14 and the third inclined surface 31 cooperate. When the tightening bolt 5 drives the pressure plate 4 to press down, the force acting on the outer sealing ring 3 will decompose part of the radial force, making the outer sealing ring 3 tightly adhere to the valve cover 7, thus achieving the second sealing surface seal. Furthermore, when the pressure of the pressure plate 4 remains constant, a portion of the non-separation force of the tightening bolt 5 will be applied radially, resulting in a better sealing effect for both the first and second sealing surfaces.

[0022] In one embodiment, such as Figures 1-7 As shown, the angle between the first inclined plane 4, the second inclined plane 15 and the upper surface of the pressure ring 1 is 30°-75°.

[0023] In one embodiment, such as Figures 1-7 As shown, the surface of the pressure plate 4 has protruding pressing portions 41, and clearance grooves 42 are formed between the pressing portions 41. The size of the clearance grooves 42 is smaller than that of the protrusions 11. This provides the pressure plate 4 with sufficient downward pressing space and avoids being blocked by the protrusions 11.

[0024] In the above embodiments, such as Figures 1-7 As shown, the upper surface dimensions of the outer sealing ring 3 and the inner sealing ring 2 are larger than the dimensions of the extrusion part 41 to ensure that the extrusion part 41 can stably apply downward pressure to the outer sealing ring 3 and the inner sealing ring 2. Because the inner sealing ring 2 and the outer sealing ring 3 are engaged with the pressure ring 1 through an inclined surface, their relative positions with the extrusion part 41 will change as the inner sealing ring 2 radially contracts and the outer sealing ring 3 radially expands. Increasing the upper surface dimensions of the inner sealing ring 2 and the outer sealing ring 3 ensures stable contact between them and the extrusion part 41.

[0025] In one embodiment, such as Figures 1-7As shown, the outer sealing ring 3 and the inner sealing ring 2 are made of PTFE. This increases the service life of the sealing rings.

[0026] In one embodiment, such as Figures 1-7 As shown, at least two tightening bolts 5 are provided, and they are distributed circumferentially around the valve stem. Preferably, three tightening bolts 5 are provided.

[0027] When using this utility model, such as Figures 1-7 As shown, by rotating the tightening bolt 5, a compressive force is applied to the pressure plate 4. The pressure plate 4 then transmits the force to the inner sealing ring 2 and the outer sealing ring 3. Due to the inclined plane, a portion of the force is distributed into radially inward and radially outward tightening forces, improving the sealing performance between the first and second sealing surfaces. If the sealing performance deteriorates due to wear or other reasons during subsequent use, simply tighten the tightening bolt 5 again.

[0028] The above are merely preferred embodiments of the present utility model and are not intended to limit the scope of implementation of the present utility model. Any modifications or equivalent substitutions to the present utility model without departing from the spirit and scope thereof should be covered within the protection scope of the claims of the present utility model.

Claims

1. A reinforced sealing structure for the stem of a plug valve, characterized in that, The valve includes a pressure ring, an inner sealing ring, an outer sealing ring, a pressure plate, and a tightening bolt. An inner cavity is formed between the valve stem and the valve cover. The pressure ring, the inner sealing ring, the outer sealing ring, and the pressure plate are sleeved on the valve stem and placed within the inner cavity. The tightening bolt is disposed on the valve cover and acts on the pressure plate. A protrusion is provided on the upper surface of the pressure ring, which divides the inner cavity into a first sealing cavity and a second sealing cavity. A first inclined surface and a second inclined surface are provided between the pressure ring and the protrusion. The outer sealing ring and the inner sealing ring are respectively disposed within the first sealing cavity and the second sealing cavity. The outer sealing ring is provided with a third inclined surface that mates with the first inclined surface, and the inner sealing ring is provided with a fourth inclined surface that mates with the second inclined surface.

2. The enhanced sealing structure for a plug valve stem according to claim 1, characterized in that, The angle between the first inclined plane, the second inclined plane and the upper surface of the pressure ring is 30°-75°.

3. The enhanced sealing structure for a plug valve stem according to claim 1, characterized in that, The surface of the pressure plate is provided with a protruding extrusion part, and a clearance groove is formed between the extrusion parts. The size of the clearance groove is smaller than that of the protrusion.

4. The enhanced sealing structure for a plug valve stem according to claim 3, characterized in that, The upper surface dimensions of the outer sealing ring and the inner sealing ring are larger than the dimensions of the extrusion section.

5. The enhanced sealing structure for a plug valve stem according to claim 1, characterized in that, The outer sealing ring and the inner sealing ring are made of PTFE.

6. The enhanced sealing structure for a plug valve stem according to claim 1, characterized in that, At least two tightening bolts are provided, and they are distributed circumferentially around the valve stem.

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