A low leakage graphite packing ring for valves

Abstract

The utility model relates to the field of valve technology, specifically a low-leakage graphite packing ring for valves, comprising a plurality of intermediate sealing rings, which are stacked and assembled from top to bottom to form a main structure, an upper packing ring is installed at the upper end of the main structure, and a lower packing ring is installed at the lower end of the main structure, the intermediate sealing ring comprises a die-pressing ring, a first upper end face cover ring is installed at the upper end of the die-pressing ring, and a first lower end face cover ring is installed at the lower end of the die-pressing ring, the die-pressing ring is formed by winding and die-pressing a flat belt, a sandwich layer is arranged on the surface of the flat belt, and the upper packing ring comprises a cut packing ring. In the low-leakage graphite packing ring for the valve, inorganic fibers with high rebound modulus, such as carbon fibers and ceramic fibers, are added to the graphite material, which effectively solves the rigidity problem of pure graphite materials, provides a certain buffer zone for friction, and thus reduces friction heat and wear. This design not only improves the sensitivity of the seal, but also significantly enhances the mechanical strength and anti-permeability of the product.

Description

Technical Field

[0001] The utility model relates to the technical field of valves, in particular to a low-leakage graphite packing ring for valves. Background Art

[0002] The sealing performance of the valve stem is the key to ensure the normal operation of the valve and prevent the leakage of the medium. Traditional valve packing rings are mostly made of pure graphite material, but pure graphite material has some obvious defects in practical applications due to its rigidity.

[0003] During the friction process, pure graphite materials tend to generate high heat, which leads to increased wear of the sealing surface, thus affecting the sealing performance and limiting the service life of the valve. In addition, the mechanical properties of pure graphite materials are relatively weak, making it difficult to meet the sealing requirements under harsh working conditions such as high pressure and high temperature. Utility Model Content

[0004] The purpose of the utility model is to provide a low-leakage graphite packing ring for valves, so as to solve the problem that pure graphite materials are prone to generate high heat during the friction process, which leads to increased wear of the sealing surface, thereby affecting the sealing performance and limiting the service life of the valve. In addition, the mechanical properties of pure graphite materials are relatively weak, and it is difficult to meet the sealing requirements under harsh working conditions such as high pressure and high temperature.

[0005] To achieve the above-mentioned purpose, the utility model provides a low-leakage graphite packing ring for valves, including a plurality of intermediate sealing rings, which are stacked and combined from top to bottom to form a main structure, an upper packing ring is installed at the upper end of the main structure, and a lower packing ring is installed at the lower end of the main structure, the intermediate sealing ring includes a molded ring, a first upper end face cover ring is installed at the upper end of the molded ring, a first lower end face cover ring is installed at the lower end of the molded ring, the molded ring is formed by winding and molding a flat strip, and a sandwich layer is provided on the surface of the flat strip, the upper packing ring includes a cut packing ring, a second upper end face cover ring is installed at the upper end of the cut packing ring, and a second lower end face cover ring is installed at the lower end of the cut packing ring.

[0006] Preferably, the flat belt of the molded ring is molded using graphite paper, mica paper, vermiculite paper, PTFE film or metal platinum sheet.

[0007] Preferably, the sandwich layer is made of inorganic fiber, specifically glass fiber, carbon fiber, ceramic fiber or basalt fiber.

[0008] Preferably, the upper packing ring and the lower packing ring have the same structure.

[0009] Preferably, the first upper end face cover ring, the first lower end face cover ring, the second upper end face cover ring and the second lower end face cover ring have the same structure and are all made of graphite paper, mica paper, vermiculite paper, PTFE film or metal platinum sheet material.

[0010] Preferably, the cut packing ring adopts a main body of a metal wire or a PTFE wire molded into an annular structure, and the gaps in the main body are filled with mica, vermiculite or graphite material.

[0011] Preferably, a plurality of first notches are disposed on the outer sides of the first upper end face cover ring and the first lower end face cover ring, and a plurality of second notches are disposed on the outer sides of the second upper end face cover ring and the second lower end face cover ring.

[0012] Preferably, a plurality of first notches are disposed on the outer sides of the first upper end face cover ring and the first lower end face cover ring, and a plurality of second notches are disposed on the outer sides of the second upper end face cover ring and the second lower end face cover ring.

[0013] Compared with the prior art, the utility model has the following beneficial effects:

[0014] The low-leakage graphite packing ring of this valve adopts sandwich layer technology, adding inorganic fibers with high rebound modulus, such as carbon fiber and ceramic fiber, to the graphite material, effectively solving the rigidity problem of pure graphite material, providing a certain buffer zone for friction, thereby reducing friction heat and wear. This design not only improves the sensitivity of the seal, but also significantly enhances the mechanical strength and anti-permeability of the product. By adopting a design with cutouts in the upper and lower packing rings, and selecting metal wire or PTFE wire as the main material, and filling mica, vermiculite or graphite materials, the adaptability and tightness of the packing ring are further improved, so that it can better adapt to the shape and movement of the valve stem, and improve the stability and reliability of the seal. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0016] Figure 2 This is a schematic diagram of the structure of the upper root ring in the utility model;

[0017] Figure 3 It is a structural schematic diagram of the middle sealing ring in the utility model;

[0018] Figure 4 It is a schematic diagram of the top view of the structure of the middle sealing ring in the utility model;

[0019] Figure 5 Schematic diagrams of four forms of the molded ring in the utility model.

[0020] The meaning of each number in the figure is:

[0021] 1. middle sealing ring; 11. molded ring; 111. sandwich layer; 12. first upper end face cover ring; 13. first lower end face cover ring; 14. first notch; 2. upper packing ring; 21. notched packing ring; 22. second upper end face cover ring; 23. second lower end face cover ring; 3. lower packing ring; 24. second notch. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] The utility model provides a low-leakage graphite packing ring for a valve, such as Figure 1-Figure 5 As shown, it includes a plurality of intermediate sealing rings 1, which are stacked from top to bottom to form a main structure, an upper packing ring 2 is installed at the upper end of the main structure, and a lower packing ring 3 is installed at the lower end of the main structure. The intermediate sealing ring 1 includes a molded ring 11, a first upper end face cover ring 12 is installed at the upper end of the molded ring 11, and a first lower end face cover ring 13 is installed at the lower end of the molded ring 11. The molded ring 11 is formed by winding and molding a flat strip, and a sandwich layer 111 is arranged on the surface of the flat strip. The sandwich layer 111 has a high rebound modulus, which solves the rigidity of pure graphite, provides a certain buffer zone for friction, and reduces frictional heat and wear; the upper packing ring 2 includes a notched packing ring 21, a second upper end face cover ring 22 is installed at the upper end of the notched packing ring 21, and a second lower end face cover ring 23 is installed at the lower end of the notched packing ring 21, which improves the anti-permeability and has a higher sealing sensitivity.

[0024] In this embodiment, the flat belt of the molded ring 11 is molded by using graphite paper, mica paper, vermiculite paper, PTFE film or metal platinum sheet.

[0025] Specifically, the sandwich layer 111 uses inorganic fibers, specifically glass fibers, carbon fibers, ceramic fibers or basalt fibers. These inorganic fibers have high rebound modulus and excellent mechanical properties, which can effectively solve the problem of excessive rigidity of pure graphite materials. By adding the sandwich layer, a certain buffer space is provided for the packing ring during the friction process, thereby significantly reducing friction heat and wear, and increasing the service life of the sealing surface. At the same time, the reinforcing effect of the inorganic fiber further improves the overall mechanical properties of the packing ring, enabling it to better adapt to the sealing requirements under harsh working conditions such as high pressure and high temperature, ensuring the long-term stable operation of the valve.

[0026] Furthermore, the upper root ring 2 and the lower root ring 3 have the same structure, ensuring the bees on the upper and lower sides.

[0027] Furthermore, the first upper end face cover ring 12, the first lower end face cover ring 13, the second upper end face cover ring 22 and the second lower end face cover ring 23 have the same structure, and are all made of graphite paper, mica paper, vermiculite paper, PTFE membrane or metal platinum sheet materials. These rings are made of high-performance materials such as graphite paper, mica paper, vermiculite paper, PTFE membrane or metal platinum sheet, which not only ensures that the rings have good wear resistance and sealing properties, but also effectively improves the overall mechanical strength and anti-permeability of the packing rings. At the same time, due to the same structure of these rings, the packing rings are more convenient in the manufacturing and installation process, reducing production costs and installation difficulties. This design not only improves the service life of the valve, but also ensures the stable operation of the valve under harsh working conditions.

[0028] Furthermore, the cut packing ring 21 adopts a main body of a metal wire or PTFE wire molded into an annular structure, and the gap in the main body is filled with mica, vermiculite or graphite material. This design not only gives the ring body good elasticity and resilience, but also enables it to effectively adapt to the shape and movement of the valve stem, thereby improving the tightness and stability of the seal.

[0029] At the same time, high-performance materials such as mica, vermiculite or graphite are filled in the main body gap of the cut packing ring 21. These filling materials not only further enhance the sealing performance of the ring body, but also effectively improve its wear resistance and anti-permeability, so that the packing ring can still maintain excellent sealing effect under harsh working conditions.

[0030] Furthermore, a plurality of first notches 14 are disposed on the outer sides of the first upper end face cover ring 12 and the first lower end face cover ring 13 , and a plurality of second notches 24 are disposed on the outer sides of the second upper end face cover ring 22 and the second lower end face cover ring 23 .

[0031] Furthermore, a plurality of first notches 14 are provided on the outer sides of the first upper end face cover ring 12 and the first lower end face cover ring 13, and a plurality of second notches 24 are provided on the outer sides of the second upper end face cover ring 22 and the second lower end face cover ring 23. The notch design also helps to improve the sealing performance of the packing ring. When the packing ring is subjected to pressure, the notch portion can undergo elastic deformation to fill the small gap between the valve stem and the packing ring, thereby improving the tightness and stability of the seal. This design enables the packing ring to maintain an excellent sealing effect under harsh working conditions.

[0032] When the low-leakage graphite packing ring of the valve of the utility model is in use, the low-leakage graphite packing ring of the valve is composed of a plurality of intermediate sealing rings 1 stacked and combined from top to bottom to form a main structure. An upper packing ring 2 is installed at the upper end of the main structure, and a lower packing ring 3 is installed at the lower end. This structural design enables the packing ring to adapt to valve stems of different lengths and ensure the tightness of the seal. The core of the intermediate sealing ring 1 is a molded ring 11, which is molded by winding a flat belt. On the surface of the flat belt, a sandwich layer 111 is provided, which is made of inorganic fiber (such as glass fiber, carbon fiber, ceramic fiber or basalt fiber) and has a high rebound modulus and excellent mechanical properties. The addition of the sandwich layer 111 provides a certain buffer zone for the packing ring during the friction process, thereby significantly reducing friction heat and wear and increasing the service life of the sealing surface.

[0033] The upper and lower ends of the molded ring 11 are respectively installed with a first upper end face cover ring 12 and a first lower end face cover ring 13. Similarly, the upper packing ring 2 and the lower packing ring 3 are also composed of a cut packing ring (such as a cut packing ring 21) and a corresponding upper end face cover ring (such as a second upper end face cover ring 22) and a lower end face cover ring (such as a second lower end face cover ring 23). These rings are made of high-performance materials such as graphite paper, mica paper, vermiculite paper, PTFE film or metal platinum sheet, ensuring good wear resistance and sealing. In addition, a plurality of first notches 14 and second notches 24 are respectively arranged on the outside of the first upper end face cover ring 12, the first lower end face cover ring 13, the second upper end face cover ring 22 and the second lower end face cover ring 23. The design of these notches not only improves the convenience of installation of the packing ring, but also helps to improve the sealing performance. When the packing ring is subjected to pressure, the notch portion can undergo elastic deformation to fill the small gap between the valve stem and the packing ring.

[0034] The main body of the notched packing ring 21 is a metal wire or PTFE wire molded into an annular structure, and the main body gap is filled with high-performance materials such as mica, vermiculite or graphite. This design gives the ring body good elasticity and resilience, enabling it to effectively adapt to the shape and movement of the valve stem, thereby further improving the tightness and stability of the seal.

[0035] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the utility model and are not used to limit the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection of the utility model is defined by the attached claims and their equivalents.

Claims

1. A low-leakage graphite packing ring for a valve, comprising a plurality of intermediate sealing rings (1), characterized in that: The intermediate sealing ring (1) is stacked and assembled from top to bottom to form a main structure, an upper packing ring (2) is installed at the upper end of the main structure, and a lower packing ring (3) is installed at the lower end of the main structure. The intermediate sealing ring (1) comprises a die pressing ring (11), a first upper end face cover ring (12) is installed at the upper end of the die pressing ring (11), and a first lower end face cover ring (13) is installed at the lower end of the die pressing ring (11). The die pressing ring (11) is formed by winding and die pressing a flat strip, and a sandwich layer (111) is provided on the surface of the flat strip. The upper packing ring (2) comprises a cut packing ring (21), a second upper end face cover ring (22) is installed at the upper end of the cut packing ring (21), and a second lower end face cover ring (23) is installed at the lower end of the cut packing ring (21).

2. The low leakage graphite packing ring for valve according to claim 1, characterized in that: The flat belt of the molded ring (11) is molded using graphite paper, mica paper, vermiculite paper, PTFE film or metal platinum sheet.

3. The low leakage graphite packing ring for valve according to claim 1, characterized in that: The sandwich layer (111) is made of inorganic fibers, specifically glass fibers, carbon fibers, ceramic fibers or basalt fibers.

4. The low leakage graphite packing ring for valve according to claim 1, characterized in that: The upper packing ring (2) and the lower packing ring (3) have the same structure.

5. The low leakage graphite packing ring for valve according to claim 4, characterized in that: The first upper end face cover ring (12), the first lower end face cover ring (13), the second upper end face cover ring (22) and the second lower end face cover ring (23) have the same structure and are all made of graphite paper, mica paper, vermiculite paper, PTFE film or metal platinum sheet material.

6. The low leakage graphite packing ring for valve according to claim 1, characterized in that: The notched packing ring (21) has a main body made of metal wire or PTFE wire molded into an annular structure, and the gaps in the main body are filled with mica, vermiculite or graphite material.

7. The low leakage graphite packing ring for valve according to claim 5, characterized in that: A plurality of first notches (14) are arranged on the outer sides of the first upper end face cover ring (12) and the first lower end face cover ring (13), and a plurality of second notches (24) are arranged on the outer sides of the second upper end face cover ring (22) and the second lower end face cover ring (23).

8. The low leakage graphite packing ring for valve according to claim 5, characterized in that: A plurality of first notches (14) are arranged on the outer sides of the first upper end face cover ring (12) and the first lower end face cover ring (13), and a plurality of second notches (24) are arranged on the outer sides of the second upper end face cover ring (22) and the second lower end face cover ring (23).

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