WO2020222420A1

WO2020222420A1 - Valve for cryogenic liquid gas

Info

Publication number: WO2020222420A1
Application number: PCT/KR2020/003355
Authority: WO
Inventors: 최동준
Original assignee: 최동준
Priority date: 2019-04-29
Filing date: 2020-03-11
Publication date: 2020-11-05
Also published as: KR102172696B1

Abstract

The present invention relates to a valve for a cryogenic liquid gas and, more specifically, to a valve provided in a use line (a gas use line and a liquid use line) of a storage tank for liquid helium or liquid hydrogen which is a cryogenic liquefied gas having a temperature less than or equal to the critical temperature of -253℃, to control a fluid flow. Particularly, the present invention relates to a valve for a cryogenic liquid gas, which has an improved structure to prevent the valve from coming into a non-operational state due to freezing or performance degradation of the valve due to a repetition of expansion and contraction in cryogenic circumstances.

Description

Valve for cryogenic liquid gas

The present invention relates to a valve for cryogenic liquid gas, and more particularly, provided in a use line (gas use line and liquid use line) of a liquid helium or liquid hydrogen storage tank, which is a cryogenic liquefied gas having a critical temperature of -253°C or less, A valve for controlling the flow of a fluid, in particular, relates to a valve for cryogenic liquid gas having an improved structure to prevent deterioration of performance or becoming inoperable due to freezing as expansion and contraction are repeated in a low temperature environment.

In general, liquefied gas refers to a state in which a gas is cooled or compressed to become a liquid, and liquefied gas is a gas that becomes a liquid by compressing a gas at room temperature and a compressed gas that is cooled and pressurized below a critical temperature other than room temperature to be liquefied. Includes.

Examples of cryogenic liquefied gases include natural gas, methane, neon, argon, helium, and hydrogen.Since these liquefied gases are stored and transported in cryogenic conditions, stable operation should be performed even in cryogenic and high-pressure gas conditions. For example, cryogenic liquid helium or liquid hydrogen is stored and transported below -253°C, and liquefied natural gas is stored and transported at cryogenic conditions below -196°C, so to store and transport these liquefied gases in high pressure or cryogenic conditions. For this, a storage tank and valve for cryogenic liquefied gas specialized in this are required.

Valves for general use are not developed to be used in conditions of high pressure and cryogenic conditions, so frequent gas leakage accidents and valve damage or damage occur, and in serious cases, explosion accidents due to high pressure expansion of the outflow liquefied gas occur. Therefore, the cryogenic liquefied gas valve used in combination with a storage tank for storing and transporting cryogenic liquefied gas such as liquid helium or liquid hydrogen or liquefied natural gas as described above is a high-pressure cryogenic environment through a handle and valve shaft that can be operated at room temperature. It is configured to effectively control the flow of liquefied gas while opening and closing operation.

Since such a valve for cryogenic liquefied gas expands not only in a cryogenic state, but also becomes an ultra-high pressure state due to intrusion of external heat, a valve that can operate while maintaining a stable airtightness even at a working pressure of 250 bar is required.

As an example of the prior art of such a valve for cryogenic liquid gas, there are Korean Utility Model Publication No. 20-0466162 (hereinafter referred to as Document 1) and Korean Registered Patent Publication No. 10-1294138 (hereinafter referred to as Document 2).

As shown in the accompanying drawings FIGS. 1 and 2, the document 1 includes an inlet chamber 10 connected to an inlet pipe having a built-in check valve that determines the inflow direction of the cryogenic fluid, and is inserted into the inlet chamber to filter impurities. In the cryogenic liquefied gas multi-valve comprising an inner filter 20 and an outlet valve 50 symmetrically formed on both sides of the inlet chamber to control the flow of cryogenic fluid passing through the filter with a valve handle, the check The valve 300 is formed of a cylindrical body having a plurality of through holes formed on the side surfaces, a push type seat 310 is formed outside the check valve, and the push type seat 310 is parallel to the connection direction of the inlet pipe. The restoring spring 320 that moves and elastically supports the check valve is installed inside the inlet chamber and fixedly formed outside the push-type seat 310, and outlet valves 50-1 formed on both sides of the inlet chamber, The valve handle of 50-2) is a multi-valve for cryogenic liquefied gas, characterized in that the valve handles are formed at different heights and do not interfere with mutual operation.

However, Document 1 has a problem in that the insulating structure for the valve is insufficient, so that the insulating effect is extremely weak, and thus, a lot of vaporization loss due to external heat occurs.

In addition, since Document 1 does not have a separate structure for isolating the valve from the outside, including the insulating structure for the valve, there is a problem in that the valve portion is easily damaged or deformed due to an external shock, resulting in an inoperable state.

On the other hand, the document 2 is a technology previously applied and registered by the applicant, as shown in the accompanying drawings, the housing 11; A lower pipe 12 accommodated in the housing 11; An upper pipe 13 fixed to an upper portion of the lower pipe 12; A stem 15 installed to be elevating through the lower pipe 12 and the upper pipe 13; A flow path opening/closing disk 17 fixed to a lower portion of the stem 15; And a first flow path 18a and a second flow path 18b that are opened and closed by the flow path opening/closing disk 17 as the stem 15 moves up and down, and forming a flow path accommodated in the housing 11. A body 18; and a vacuum is formed inside the housing 11, so that the flow path forming body 18 and the lower pipe 12 accommodated in the housing 11 are transferred to the housing 11 ) Can be insulated against the external environment, a packing is disposed between the inner surface of the upper pipe 13 and the outer surface of the stem 15, and the inner diameter of the upper end of the lower pipe 12 is the upper By being formed larger than the outer diameter of the lower end of the pipe 13, when the lower end of the upper pipe 13 is inserted into the upper end of the lower pipe 12, the outer peripheral surface of the lower end of the upper pipe 13 and the lower pipe It is a valve for cryogenic fluid in which an O-ring is interposed between the inner peripheral surface of the upper end of (12).

Document 2 describes that by creating a vacuum environment inside the housing 11, the flow path forming body 18 and the lower pipe 12 accommodated in the housing 11 are transferred to the external environment of the housing 11. Since it can insulate against, it is a technology that secures a thermal insulation effect and stability against external impacts compared to Document 1 above.

However, since Document 2 merely creates a vacuum environment inside the housing 11, there is a problem in that the insulation efficiency is low, and thus, there is a limit in completely preventing vaporization loss due to external heat.

Prior literature related to the valve for cryogenic liquid gas as described above is as follows.

Document 1: Republic of Korea Utility Model Publication No. 20-0466162 (Name: Multi-valve for cryogenic liquefied gas; filing date: December 15, 2010)

Document 2: Korean Registered Patent Publication No. 10-1294138 (Name: valve for cryogenic fluid; filing date: October 7, 2011)

The present invention was created to solve the problems of the prior art as described above, and is provided in the use line (gas use line and liquid use line) of a liquid helium or liquid hydrogen storage tank, which is a cryogenic liquefied gas having a critical temperature of -253°C or less. An object of the present invention is to provide a valve for a cryogenic liquid gas having an improved structure to prevent deterioration of performance or becoming inoperable due to freezing as a result of repeated expansion and contraction in a low temperature environment.

In the present invention for achieving the above object, the valve body 11 is provided with an opening/closing portion 11a inside, and liquid gas pipes 1'and 1'at both ends thereof being connected; the opening/closing portion 11a ) Corresponding to the vertical pipe portion 12 fixed in communication above the valve body portion 11; in a state inserted into the vertical pipe portion 12, opening and closing while ascending and descending by a rotation operation with respect to the opening and closing portion 11a Operation unit 13 provided with rotation knobs 13a and openings 13b at both ends to operate; airtight holding unit that maintains airtightness of the portion through which the operation unit 13 passes while being coupled to the front end of the vertical tube unit 12 A pearlite vacuum insulation unit 15 forming a pearlite vacuum insulation structure for a portion of the liquid gas pipes 1 ′ and 1 ″ at both ends of the valve body 11 and a part of the vertical pipe 12; It characterized in that it includes; a pipe vacuum insulation unit 16 forming a vacuum insulation structure for the liquid gas pipes (1') (1") from both ends of the pearlite vacuum insulation unit (15).

The present invention according to the problem solving means as described above is a pearlite vacuum insulation structure for a part of the liquid gas pipe (1') (1") at both ends of the valve body part 11 and a part of the vertical pipe part 12 The liquid gas pipe (1') is formed by forming a vacuum insulating part 16 which is a vacuum insulating structure with respect to the liquid gas pipe 1'(1") from both ends of the part 15 and the pearlite vacuum insulating part 15. In addition to preventing the liquid gas flowing along (1") from being vaporized by external heat, the valve 10 part is prevented from deteriorating performance or becoming inoperative due to freezing due to repeated expansion and contraction in a low temperature environment. Get the effect.

In addition, the present invention is provided in a vertical direction with respect to the opening and closing portion (11a) by forming the pearlite vacuum insulation portion 15, which is a pearlite vacuum insulation structure, up to the vertical tube portion 12 communicating with the valve body portion 11, An effect of preventing the operation portion 13 that passes through the vertical tube portion 12 and moves up and down by a rotation operation is prevented from becoming inoperative due to freezing.

In addition, in the present invention, the liquid gas pipe (1') (1") and the operation part 13 connected to the valve body part 11 are double wrapped around the pearlite vacuum insulation part 15 and the vertical pipe part 12 By consisting of a structure to protect, the effect of improving the durability, safety and stability of the valve 10 is obtained.

In addition, in the present invention, the valve body 11 and the liquid gas pipe (1') (1") are connected to each other by double-insulating treatment with the pearlite vacuum insulation section 15 and the valve vacuum insulation section 17, It is possible to provide a multi-faceted and three-dimensional insulation and high vacuum environment for the valve 10, and thereby, an effect of minimizing the occurrence of natural vaporization is obtained by suppressing the vaporization increase pressure of the liquid gas.

1 is a cross-sectional view showing an example of a conventional liquefied gas valve.

Figure 2 is a cross-sectional view showing an example of a conventional liquefied gas valve.

3 is a cross-sectional view showing another example of a conventional liquefied gas valve.

4 is a cross-sectional view showing an example of the configuration or structure of the present invention.

5 is a cross-sectional view showing another example of the configuration or structure of the present invention.

6 and 7 are partial cross-sectional views showing the valve opening and closing operation of the present invention.

The present invention will be described with reference to the accompanying drawings presented as described above.

As shown in the accompanying drawings, the valve 10 for cryogenic liquid gas 10 is a valve in which an opening and closing portion 11a is provided inside, and a liquid gas pipe 1 ′ and 1 ″ is connected at both ends thereof, as shown in FIG. 4. Main body 11; A vertical pipe portion 12 fixed in communication above the valve body 11 in correspondence with the opening and closing portion 11a; The opening and closing portion 12 in a state of being inserted into the vertical pipe portion 12 ( The operation unit 13 provided with a rotation knob 13a and an opening/closing hole 13b at both ends, respectively, so as to open and close by rotating operation for 11a); the operation unit 13 is coupled to the front end of the vertical tube part 12 Airtightness maintenance part 14 to keep the airtightness of the penetrating part; Pearlite vacuum insulation structure for part of the liquid gas pipe (1') (1") at both ends of the valve body part 11 and part of the vertical pipe part 12 Pearlite vacuum insulation unit 15 to form a; It may include a pipe vacuum insulation unit 16 forming a vacuum insulation structure for liquid gas pipes 1 ′ and 1 ″ from both ends of the pearlite vacuum insulation unit 15.

Here, the valve 10 for cryogenic liquid gas according to the present invention may be installed and applied to a gas or liquid gas use line of a cryogenic liquid gas storage tank.

Meanwhile, in the present invention, the liquid gas may be a cryogenic to cryogenic gas including oxygen, nitrogen, carbonic acid, nitrous oxide, natural gas, methane, neon, argon, helium, and hydrogen.

On the other hand, in the present invention, the valve body 11 is a three-way open space in which a liquid gas pipe (1') (1") is connected to each of both ends, and the vertical pipe portion 12 is fixed by a perforation in the upper middle It can be a sieve.

In the above, the opening/closing portion 11a may be formed by dividing both ends to which the liquid gas pipes (1') (11") are connected, a partition wall having a horizontal hole formed in the middle of the space of the valve body (11). have.

In addition, the valve body 11 is a three-way open type in which the liquid gas pipes 1'and 1" are respectively connected to each other in a horizontal direction, and the upper middle is perforated to fix the vertical pipe 12 It can also be block.

In this case, the opening/closing portion 11a may have a circular space formed at an intermediate portion penetrating in the horizontal direction in the space of the valve body 11.

On the other hand, in the present invention, one end of the vertical pipe part 12 is fixed in a state in communication with the upper part of the valve body part 11, and the other end extending in the vertical direction may be a pipe having a flange.

On the other hand, in the present invention, the operation part 13 is provided with a rotation knob 13a at one end exposed to the outside, and a through hole corresponding to the opening/closing part 11a at the other end of the valve body 11 An opening and closing opening (13b) for opening and closing is provided, and a part of the outer diameter located in the vertical pipe portion 12 may be a stem that is engaged by an inner diameter of the vertical pipe portion 12 and a screw thread, and lifts and descends by a rotation operation.

In this case, the opening/closing opening 13b may be a blocking member that is in close contact with or detaches from the through hole, which is the opening/closing part 11a.

In addition, the operation unit 13 may be a stem that is rotated limited to a 90 degree angle in a state in close contact with the inner diameter of the vertical tube unit 12.

In this case, the opening/closing opening 13b may be a ball valve body that communicates or blocks both ends of the valve body 11 while limited rotation within a 90 degree angle in a state in close contact with the circular space of the opening/closing portion 11a.

On the other hand, in the present invention, the airtight holding part 14 is a pipe body having a flange formed at one end, and protruding through while being coupled to the front end of the vertical pipe part 12 to maintain airtightness while supporting the operation part 13 I can.

The flange of the airtight holding part 14 may be in close contact with the flange of the vertical tube part 12 through screw coupling.

On the other hand, in the present invention, the pearlite vacuum insulation unit 15 surrounds a part of the outer diameter of the liquid gas pipe 1'(1") and vertically fixed vertical pipe 12 coupled to both ends of the valve body 11 approximately 5 × 10 ^- a vacuum enclosure (15a) for forming a vacuum in the closed space ² Torr; may be the hayeoseo including; perlite (15b) that is filled in the vacuum housing (15a).

The vacuum enclosure 15a may be further provided such that a path in which pearlite is charged and an air intake path are connected to the outside in order to create a vacuum environment.

On the other hand, in the present invention, the pipe vacuum insulator 16 is provided along the liquid gas pipe 1') (1") from the pearlite vacuum insulator 15 at the liquid gas pipe (1') (1") side. As an external pipe, it may be to create a high vacuum environment of about 10 ^-3 Torr.

The pipe vacuum insulation unit 16 is alternately wound in several layers using silver foil as a reflective material and a special insulation paper as a shielding material on the surface located in the space between the liquid gas pipes (1') (1") and the external pipes, and then about 10 ^It can also consist of a super-insulation insulation treatment structure that creates a high vacuum environment of ^-3 Torr.

And, the present invention, as shown in the accompanying drawings Figure 5, by forming a double space between the pearlite vacuum insulation unit 15 and the liquid gas pipe (1') (1") including the valve body (11) , It may be made by further providing the valve vacuum insulation unit 17.

The valve vacuum insulator 17 is a pipe surrounding the valve body 11 and the liquid gas pipes 1 ′ and 1 ″ and may create a high vacuum environment of about 10 ^-3 Torr.

In this case, the valve vacuum insulator 17 may be further provided with an air intake path connected to the outside to create a vacuum environment.

The operation of the present invention will be described as follows.

In the present invention, the valve body 11 is provided with an opening and closing portion 11a therein, and liquid gas pipes 1'and 1'at both ends thereof are connected; the valve body portion corresponding to the opening and closing portion 11a Vertical tube part 12 fixed in communication above the upper part of (11); each rotated at both ends so as to open and close by rotating operation with respect to the opening/closing part 11a while being inserted into the vertical tube part 12 An operation part 13 provided with a knob 13a and an opening/closing hole 13b; An airtight holding part 14 coupled to the front end of the vertical tube part 12 to maintain airtightness of a portion through which the operation part 13 passes; the valve body A pearlite vacuum insulation unit 15 for forming a pearlite vacuum insulation structure for a portion of the liquid gas pipes 1 ′ and 1 ″ at both ends of the unit 11 and a part of the vertical pipe 12; It is a valve 10 for cryogenic liquid gas including a pipe vacuum insulation unit 16 forming a vacuum insulation structure from both ends of the pearlite vacuum insulation unit 15 to the liquid gas pipes 1 ′ and 1 ″. .

Here, the valve 10 for cryogenic liquid gas according to the present invention is installed and applied to a gas or liquid gas use line of a cryogenic liquid gas storage tank.

Meanwhile, in the present invention, the liquid gas is a cryogenic to cryogenic gas including oxygen, nitrogen, carbonic acid, nitrous oxide, natural gas, methane, neon, argon, helium, and hydrogen, and in the present invention, cryogenic liquid helium and liquid hydrogen are used. Let it be an Example.

On the other hand, in the present invention, the valve body 11 is a space body in which liquid gas pipes 1 ′ and 1 ″ are respectively connected to both ends, and the vertical pipe part 12 is fixed by perforating the upper middle.

In the above, the connection portion between the valve body 11 and the liquid gas pipe (1') (1") and the fixed portion of the vertical pipe portion 12 may be sealed to be kept airtight, and the outer diameter of each connection portion It is preferable that a screw thread is formed on the inner diameter and is helically coupled or welded to each other.

In addition, in the above, the opening and closing portion 11a is formed by dividing both ends to which the liquid gas pipes (1') (11") are connected by a partition wall formed with a through hole in the horizontal direction in the middle portion of the space of the valve body (11). Thus, in the state where the opening/closing opening 13b of the operation part 13 is separated from the block due to the elevation, the liquid gas pipe 1 ′ is connected to the liquid gas pipe 1 ″ in the discharge direction. Communicate or block.

On the other hand, in the present invention, one end of the vertical pipe part 12 is fixed in a state in communication with the upper end of the valve body part 11, and the other end extending in the vertical direction is a flanged pipe body. The operation part 13 is provided with a rotation knob 13a at one end exposed to the outside, and an opening/closing opening 13b for opening and closing the through hole corresponding to the opening/closing part 11a at the other end of the valve body 11 Is provided, and a part of the outer diameter located in the vertical pipe portion 12 is a stem that is engaged by the inner diameter of the vertical pipe portion 12 and a screw thread, and is raised and lowered by a rotation operation, and the airtight holding portion 14 of the present invention Is a pipe body having a flange formed at one end thereof, and protrudes through while being coupled to the front end of the vertical pipe part 12 to maintain airtightness while supporting the operation part 13.

As shown in the accompanying drawings Figures 6 and 7, the present invention, when rotating the rotation knob (13a), when the opening (13b) is in close contact with the opening and closing portion (11a) while elevating It blocks or allows the flow of liquid gas while leaving.

In addition, the operation part 13 is made of a stem that is rotated limited to a 90 degree angle in a state in close contact with the inner diameter of the vertical tube part 12, and the opening 13b is in close contact with the circular space which is the opening and closing part 11a. In this state, it is also preferable that the ball valve body communicates or blocks both ends of the valve body 11 while limited rotation within a 90 degree angle.

In addition, the present invention rotates and moves up and down in the vertical pipe portion 12 in a state in which the operation portion 13 vertically drawn into the vertical pipe portion 12 is isolated from the outside, and the airtight holding portion 14 The flange and the flange at the front end of the vertical pipe portion 12 are closely coupled, so that airtightness is maintained with respect to the portion through which the operation portion 13 passes.

In the above, the flange of the airtight holding portion 14 is in close contact with the flange of the vertical pipe portion 12 through screwing, and it is preferable that an O-ring and an airtight holding pad are stacked on the contact surface.

On the other hand, in the present invention, the pearlite vacuum insulation unit 15 surrounds a part of the outer diameter of the liquid gas pipe 1'(1") and vertically fixed vertical pipe 12 coupled to both ends of the valve body 11 approximately 5 × 10 ^- a vacuum enclosure (15a) for forming a vacuum in the closed space ² Torr; would include the hayeoseo; perlite (15b) that is filled in the vacuum housing (15a).

It is preferable that the liquid gas pipe (1') (1") and the vacuum enclosure (15a) in contact with the vertical pipe portion (12) are welded to maintain airtightness.

In addition, the vacuum enclosure (15a) is further provided with a path for filling pearlite and an air intake path to create a vacuum environment.

On the other hand, in the present invention, the pipe vacuum insulator 16 is provided along the liquid gas pipe 1') (1") from the pearlite vacuum insulator 15 at the liquid gas pipe (1') (1") side. As an external piping, it creates a high vacuum environment of about 10 ^-3 Torr.

It is preferable that a portion in contact with the pearlite vacuum insulation unit 15 is welded to maintain airtightness.

In addition, in the above, the pipe vacuum insulation unit 16 is alternately wound in several layers using silver foil as a reflective material and special insulation paper as a shielding material on the surface located in the space between the liquid gas pipe (1') (1") and the external pipe. , It is also preferable to have a super-insulation heat-insulating treatment structure that creates a high vacuum environment of about 10 ^-3 Torr.

For reference, assuming that the annual average temperature in Korea is 20℃, the temperature inside and outside the path where liquid gas is stored or flowed is 216℃ for nitrogen with a boiling point of -196℃, and 182℃ for LNG at -162℃ and 79℃. Phosphorus liquid carbonic acid has a significant difference at 99°C. When a vacuum through insulation cannot be secured due to this phenomenon, the liquid gas is vaporized due to an increase in temperature and changes to a gaseous state. In the case of nitrogen or LNG, the volume increases approximately 600 to 700 times, resulting in an enormous increase in the storage tank 10. A pressure increase occurs.

The heat conductivity of vacuum in the pearlite pearlite vacuum insulation, but vary slightly depending on the filling density of the perlite, ideal thermal conductivity in the charge density is at atmospheric pressure cryogenic 2x10 ^- when about ² Kcal / m2h ℃. However, since the temperature difference between the ambient temperature and the cryogenic temperature can be around 200℃ or higher, an absolutely effective and economical insulation construction must be performed.

Therefore, in order to solve the above problems and to more effectively use the thermal conductivity of 2×10-2Kcal/m2h°C, the pearlite-filled thermal insulation space is vacuum-treated, and the pearlite vacuum insulation method is applied.

The higher the degree of vacuum in the insulated space, the slower the diffusion rate of air molecules in the vacuum and the lower the heat conduction. However, too high a degree of vacuum is less economical and has little meaning as a vacuum.

According to the results of several experiments, in the case of the pearlite vacuum insulating structure, the thermal conductivity of pearlite is dominated below a certain degree of vacuum, but the thermal conductivity of a certain value is obtained at higher vacuum degree. To economically degree of vacuum 5 × 10 ^-2 Torr valid under this condition, wherein the perlite of the thermal conductivity of the vacuum insulation is 2.4 × 10 ^- ² is in Kcal / m2h ℃, perlite vacuum insulation is by a factor of 10 compared with the normal pressure pearlitic heat intrusion Is reduced.

In addition, the vacuum insulation structure, in particular, the super insulation insulation structure is suitable for cryogenic storage containers such as liquid helium (LHe) and liquid hydrogen (LH2), or when the ratio of the surface area to the inner volume is large.

Super Insulation Insulation method is designed to minimize heat transfer due to conduction, convection, and radiation. It is about 1/10 of the thickness of pearlite vacuum insulation, so it is suitable for light weight and miniaturization, so it is combined with pearlite vacuum insulation. It is desirable to apply.

In order to block convective heat generated by using air as a medium, the super insulation insulation method is made of a higher vacuum than pearlite vacuum insulation. Insulation is a multi-layered insulator instead of pearlite, which is wrapped around the outer surface of a liquid gas pipe (1') (1") in several layers. This reflector only contacts the liquid gas pipe (1') (1") and contacts the inner wall of the outer pipe. It is more preferable not to contact with. These reflectors are effective in greatly reducing radiant heat entering the inner tank from the outside by reducing the temperature of the radiant heat from the outside by each layer of the reflector. Radiant heat from the outside is reduced by each layer of the reflector, greatly reducing the radiant heat from the outside to the inner tank.

And, the present invention, as shown in the accompanying drawings Figure 5, by forming a double space between the pearlite vacuum insulation unit 15 and the liquid gas pipe (1') (1") including the valve body (11) , as a pipe wrap to be hayeoseo valves further include a vacuum thermal insulating unit 17, the valve vacuum adiabatic portion 17 of the valve body portion 11 and the liquid gas pipe (1 ') (1 "), about 10 ^{- 3} Torr high vacuum environment is created.

In this case, the pipe constituting the valve vacuum insulation unit 17 may be a portion connected to the valve body 11 and the pearlite vacuum insulation unit 15 is welded to maintain airtightness.

In the present invention as described above, the liquid gas pipe (1') (1") and the operation part (13) connected to the valve body part (11) are doubled with the pearlite vacuum insulation part (15) and the vertical pipe part (12). By being made of a structure that wraps and protects, durability, safety and stability of the valve 10 are improved.

In addition, the valve body 11 and the liquid gas pipe (1') (1") are connected to each other by double-insulating treatment with pearlite vacuum insulation unit 15 and valve vacuum insulation unit 17, 10) It is possible to provide a multi-faceted and three-dimensional insulation and high vacuum environment, and through this, it is possible to minimize the occurrence of natural vaporization by suppressing the vaporization pressure of liquid gas.

As described above, the present invention has been described and illustrated in connection with a preferred embodiment for illustrating the principle of the present invention, but the present invention is not limited to the configuration and operation as illustrated and described as such.

In addition, it will be well understood by those skilled in the art that many changes and modifications can be made to the present invention without departing from the spirit and scope of the appended claims.

Accordingly, all such appropriate changes and modifications and equivalents should be considered to be within the scope of the present invention.

Claims

In the cryogenic liquid gas valve 10,

A valve body portion 11 provided with an opening and closing portion 11a therein, and to which liquid gas pipes 1'and 1'are connected at both ends;

A vertical pipe portion 12 fixed in communication above the valve body portion 11 corresponding to the opening/closing portion 11a;

An operation unit 13 provided with a rotation knob 13a and an opening and closing port 13b at both ends, respectively, so as to open and close while moving up and down by a rotation operation with respect to the opening/closing portion 11a in a state inserted into the vertical tube portion 12;

An airtight holding part 14 coupled to the front end of the vertical tube part 12 and maintaining airtightness of a portion through which the operation part 13 passes;

A pearlite vacuum insulation unit 15 for forming a pearlite vacuum insulation structure for a portion of the liquid gas pipes 1 ′ and 1 ″ at both ends of the valve body 11 and a portion of the vertical pipe 12;

Including a pipe vacuum insulation unit 16 forming a vacuum insulation structure for the liquid gas pipes 1'and 1'from both ends of the pearlite vacuum insulation unit 15,

Valve for cryogenic liquid gas, characterized in that.
The method according to claim 1,

The liquid gas is liquid helium or liquid hydrogen,

Valve for cryogenic liquid gas, characterized in that.
The method according to claim 1,

The perlite vacuum insulation unit 15 includes a valve body portion liquid gas pipe coupled to 11, two ends (1 ') (1 ") and about 5 × 10 enclosing a portion the outer diameter of the vertical tube 12 which is vertically fixed-2 A vacuum enclosure (15a) forming a vacuum sealed space of Torr;

Pearlite (15b) filled in the vacuum enclosure (15a); Including,

Valve for cryogenic liquid gas, characterized in that.
The method of claim 3,

The pipe vacuum insulator 16 is an external pipe provided along the liquid gas pipe 1') (1") from the pearlite vacuum insulator 15 at the liquid gas pipe (1') (1") side. To create a high vacuum environment of -3 Torr,

Valve for cryogenic liquid gas, characterized in that.
The method according to claim 1,

The pipe vacuum insulation unit 16 is alternately wound in several layers using silver foil as a reflective material and a special insulation paper as a shielding material on the surface located in the space between the liquid gas pipes (1') (1") and the external pipes, and then about 10 It is made of super-insulation insulation treatment structure that creates a high vacuum environment of -3 Torr,

Valve for cryogenic liquid gas, characterized in that.
The method according to claim 1,

By forming a double space between the pearlite vacuum insulation unit 15 and the liquid gas pipe (1') (1″) including the valve body unit 11, a valve vacuum insulation unit 17 is further provided,

Valve for cryogenic liquid gas, characterized in that.
The method according to claim 1,

The cryogenic liquid gas valve 10 is installed and applied to a gas or liquid gas use line of a cryogenic liquid gas storage tank,

Valve for cryogenic liquid gas, characterized in that.