CN209688240U - A kind of cryogenic valve fugacity composite filling structure - Google Patents

Abstract

A kind of cryogenic valve fugacity composite filling structure, including valve deck, valve rod are formed with clearance space, are successively arranged the first resealing, the second resealing in clearance space from the bottom up between the valve rod and the inner cavity of valve deck；First resealing is spring energy-storage sealing ring, and spring energy-storage sealing ring is mounted on first of sleeveless jacket at valve deck；Second resealing includes the V-type PCTFE filler of the upper half and the leaching asbestos PTFE filler of lower half.A kind of cryogenic valve fugacity composite filling structure provided by the utility model, good seal performance, security level are high.

Description

A fugitive composite packing structure for ultra-low temperature valves

technical field

The utility model relates to an ultra-low temperature valve, in particular to a fugitive combined packing structure for an ultra-low temperature valve.

Background technique

With the continuous development of science and technology and the chemical industry, the application of cryogenic valves in the cryogenic industry is becoming more and more extensive. At present, the research work on cryogenic valves at home and abroad is also constantly advancing to meet the rapid development of modern industrialization. Now the country implements the localization policy on major industrial equipment and key devices, and the demand for domestic low-temperature valves in many low-temperature projects is increasing year by year, so the requirements for their safety performance are also getting higher and higher. This requires special design of the sealing packing structure and special selection of sealing packing materials in the design process of cryogenic valves to meet the sealing requirements of cryogenic valves. Only in this way can the safe operation of the system be guaranteed, and the working condition requirements of cryogenic valves in terms of function, reliability and safety performance can be met. At the same time, it can also reduce pollution and harm to the environment and personal injury, and reduce the possibility of dangerous accidents. Therefore, high requirements are placed on the sealing performance of cryogenic valves.

Utility model content

The technical problem to be solved by the utility model is to provide a fugitive combined packing structure for ultra-low temperature valves, which has good sealing performance and high safety level, and overcomes the problem of leakage of packing glands of existing ultra-low temperature valves.

In order to solve the problems of the technologies described above, the technical solution adopted in the utility model is:

A fugitive composite packing structure for an ultra-low temperature valve, including a valve cover and a valve stem. A space is formed between the valve stem and the inner cavity of the valve cover, and the first seal, The second heavy seal; the first heavy seal is a spring energy storage seal ring, and the spring energy storage seal ring is installed on the first shoulder of the valve cover; the second heavy seal includes a V-shaped PCTFE packing in the upper half and asbestos-impregnated PTFE packing in the lower half.

A T-shaped guide sleeve is provided between the spring energy storage sealing ring and the asbestos-impregnated PTFE packing, and a packing pressure sleeve is provided at the top of the V-shaped PCTFE packing.

The upper end of the packing gland is sequentially provided with a first disc spring and a packing pressing plate, wherein the packing pressing plate is connected with the valve cover through a fastening component.

The fastening assembly includes a stud and a nut, and a second disc spring is sleeved on the stud between the nut and the packing pressure plate.

The utility model is a fugitive combined packing structure for ultra-low temperature valves, which has the following technical effects:

1) The spring energy storage sealing ring adopts high-performance seals with springs in the PCTFE jacket, which can be used in most chemical fluids, solvents, and hydraulic oil dynamic seals, static seals, single-acting and double-acting and other occasions . The elastic compensation provided by the spring can overcome the slight eccentricity of the metal mating surface and the wear of the sealing lip, and continue to maintain the expected sealing performance. PCTFE material has excellent gas barrier ability, good chemical stability and heat resistance, and is suitable for long-term use under low temperature conditions of -196°C.

2) The combination structure of V-type PCTFE packing installed on the upper half and impregnated PCTFE asbestos packing installed on the lower half is used as the second seal of the valve. This structure is suitable for low-temperature conditions such as flammable media and low density.

3) A set of first disc spring is added between the packing pressure plate and the packing sleeve. When the packing is worn out, the packing will be re-pressed by the force of the disc spring to make it seal.

4) Add a set of second disc springs under the nuts of the fasteners to prevent the nuts from loosening, so that the safety and practicability of the valve are more guaranteed.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described:

Fig. 1 is a sectional view of the utility model.

In the figure: valve cover 1, spring energy storage sealing ring 2, T-shaped guide sleeve 3, asbestos-impregnated PTFE packing 4, V-shaped PCTFE packing 5, packing pressure sleeve 6, first disc spring 7, packing pressure plate 8, second disc Spring 9, stud 10, nut 11, valve stem 12.

Detailed ways

As shown in Figure 1, a fugitive composite packing structure for ultra-low temperature valves includes a valve cover 1 and a valve stem 12. A space is formed between the valve stem 12 and the side wall of the inner cavity of the valve cover 1, and the spring stores energy. Sealing ring 2, T-shaped guide sleeve 3, asbestos-impregnated PTFE packing 4, V-shaped PCTFE packing 5, packing pressure sleeve 6, disc spring 7, and packing pressure plate 8 pass through the valve stem 12 in sequence to complete the filling and sealing of the interval space. The packing pressing plate 8 and the valve cover 1 are integrally connected by studs 10 and nuts 11 .

A method for sealing an ultra-low temperature valve. An interval space is provided between the valve cover 1 and the valve stem 12, and two vestibules are provided on the side wall of the inner cavity of the valve cover 1. The first vestibule is provided with a first heavy seal, and the second A second seal is provided outside the vest; the first seal is sealed with a spring energy-storage seal ring 2, and the second seal is sealed with a combined structure of V-shaped PCTFE packing 5 in the upper part and asbestos-impregnated PTFE packing 4 in the lower part. When the packing is worn out, the packing will be pressed again due to the force of the first disc spring to make it seal.

Claims (4)

1. A fugitive composite packing structure for an ultra-low temperature valve, including a valve cover (1) and a valve stem (12), characterized in that: a valve stem (12) and the inner cavity of the valve cover (1) are formed with In the interval space, the first heavy seal and the second heavy seal are arranged sequentially from bottom to top; the first heavy seal is a spring energy storage sealing ring (2), and the spring energy storage sealing ring (2) is installed on the valve On the first waistcoat at the cover (1); the second seal includes V-shaped PCTFE packing (5) on the upper half and asbestos-impregnated PTFE packing (4) on the lower half. 2. A fugitive combined packing structure for ultra-low temperature valves according to claim 1, characterized in that: a T-shaped guide sleeve is provided between the spring energy storage sealing ring (2) and asbestos-impregnated PTFE packing (4) (3), V-shaped PCTFE packing (5) is provided with a packing gland (6) at the top. 3. A fugitive combined packing structure for ultra-low temperature valves according to claim 2, characterized in that: the upper end of the packing gland (6) is provided with a first disc spring (7) and a packing pressing plate (8) in sequence, Wherein, the packing pressing plate (8) is connected with the valve cover (1) through a fastening component. 4. A fugitive composite packing structure for ultra-low temperature valves according to claim 3, characterized in that: the fastening assembly includes studs (10), nuts (11), and the nuts (11) are located on the studs (10) 11) There is a second disc spring (9) between the packing plate (8).