JP2000018498A - Pressure control device for cryogenic container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To bring airtightness into full play even after cryogenic gas has blown off. SOLUTION: In this pressure control device for a cryogenic container 13, which opens a valve element 29 closing a discharge port 26a at the side of a valve seat 26 and makes the gas of a cryogenic fluid so as to be discharged out of the discharge port 26a when pressure in the cryogenic container 13 wherein this cryogenic fluid is stored, has exceeded the setting pressure, each ridge line part, whose section is quadrilateral and existing in a diagonal line, is made so as to become the axial direction, for example, a ring seal member 33 is made up with high polymer resin having flexibility at a temperature of, e.g. 200 deg.C, and the ridge line part at the axial one end side of the seal member 33 is made to come into contact with the valve seat 26 around the discharge port 26a, and another ridge line part at the other end side is made so as to be contacted with the valve element 29.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure control device for a cryogenic container for adjusting the pressure in a cryogenic container for storing liquid helium, liquid nitrogen or the like.

[0002]

2. Description of the Related Art FIG. 7 is a sectional view showing a conventional pressure adjusting device for a cryogenic container. In FIG. 7, a pipe 3 connects between a low-temperature container 1 in which liquid helium, liquid nitrogen and the like are stored and a main body 2. Then, the spring seat 5 having the through hole 5 a is fixed by the valve seat 4 screwed to the main body 2, and the space between the main body 2 and the valve seat 4 is hermetically sealed by the seal member 6. Further, the valve body 9 is pressed against the valve seat 4 by the spring 8 compressed to a predetermined pressure between the spring seat 5 and the spring seat 7. The hermetic sealing is performed by deforming the sealing member 10 having a doughnut-shaped cross section disposed between the valve seat 4 and the valve element 9. In the above configuration, when the spring force FS is determined by the spring constant of the spring 8 and the compression amount of the spring, and the gas pressure FG is determined by the gas pressure in the low-temperature container 1 and the pressure receiving area of the valve element 9, the inside of the low-temperature container 1 When the pressure rises and FS <FG, the valve body 9 moves against the spring force FS, and the airtightness between the valve body 9 and the seal member 10 is lost. The pressure FG decreases. When FS> FG, the airtightness is again exerted between the valve body 9 and the seal member 10 by the spring force FS, so that the gas pressure in the low-temperature container 1 can be maintained at a predetermined value.

[0003]

Since the conventional pressure adjusting device for a cryogenic container is constructed as described above, when the valve element 9 is actuated and gas in the cryogenic container 1 is blown out, the pressure is reduced by -10.
Since the temperature is 0 ° C. or less, if the amount of gas blowout becomes large or the gas blows out frequently, the seal member 10 may be cooled and freeze.
Therefore, when the gas pressure in the low temperature vessel 1 decreases,
Even if the valve body 9 presses the sealing member 10 again, the sealing member 1
Since 0 freezes and does not deform, there is a problem that it is difficult to exhibit sufficient airtightness. The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a pressure adjusting device for a low-temperature container that can exhibit airtightness even after a low-temperature fluid is blown out. It is.

[0004]

According to the present invention, there is provided a pressure adjusting device for a cryogenic container, wherein a valve closing a discharge port on a valve seat side when a pressure of a cryogenic container storing a cryogenic fluid exceeds a set pressure. In a pressure adjusting device for a cryogenic container in which the body is opened to release the gas of the cryogenic fluid from the discharge port, the cryogenic fluid is controlled so that each of the diagonal ridges having a cross-section is in the axial direction. An annular seal member is formed of a polymer resin having flexibility even in a temperature range, and the ridge portion at one end in the axial direction of the seal member is brought into contact with the valve seat around the discharge port, and the ridge at the other end is formed. The part is brought into contact with the valve body. Also, a pair of seals formed in a ring shape from a polymer resin having flexibility even in the temperature range of the low-temperature fluid is formed by a pair of seals so that each ridge portion present on a diagonal line having a cross section in a diagonal line is in the axial direction. The sealing member is formed by integrating the facing ridge portions with each other in the direction, and the ridge portion at one end in the axial direction of the sealing member is brought into contact with the valve seat around the discharge port, and the ridge at the other end is formed. The part is brought into contact with the valve body. In addition, a pair of seals formed concentrically with a polymer resin having flexibility even in the temperature range of the low-temperature fluid are concentrically arranged so that each of the ridges present on a diagonal line having a cross section of a quadrangle is in the axial direction. The sealing member is formed by integrating the opposed ridge portions, and each ridge portion on one end side in the axial direction of the sealing member is brought into contact with the valve seat around the discharge port, and the other end portion is formed. Each ridge portion is brought into contact with the valve body. Furthermore, a pair of seals formed in a ring shape from a polymer resin having flexibility even in the temperature range of the low-temperature fluid, so that each of the ridges present on a diagonal line having a cross-section in a quadrilateral form is in the axial direction. In the direction, and form a pair of sealing body groups by integrating the facing ridge parts, and a ridge part present on the inner peripheral side of one of the sealing body groups by arranging the sealing body groups concentrically, A sealing member is formed by integrating the ridges existing on the outer peripheral side of the other seal body group, and each ridge at one axial end of the sealing member is brought into contact with the valve seat around the discharge port, The ridges on the other end are brought into contact with the valve body.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a configuration diagram showing a low-temperature fluid storage device using the low-temperature container pressure adjusting device of the first embodiment, FIG. 2 is a cross-sectional view showing the low-temperature fluid pressure adjusting device of the first embodiment, and FIG. FIG. 3 is a sectional view illustrating a main part of FIG. 2. 1 to 3, reference numeral 11 denotes an inner tank, which stores a low-temperature fluid 14 described later. Reference numeral 12 denotes an outer tank that covers the inner tank 11 and is configured so that the space between the outer tank and the inner tank 11 is evacuated. In addition, inner tank 1
1. The low temperature container 13 is constituted by the outer tank 12.
Reference numeral 14 denotes a low-temperature fluid stored in the inner tank 11, such as liquid helium or liquid nitrogen. An injection port 15 for filling the low-temperature fluid 14 is provided with an on-off valve 16. Reference numeral 17 denotes an outlet for the low-temperature fluid 14, which is provided with an on-off valve 18.
Reference numeral 19 denotes a gas release valve for discharging gas in the inner tank 11. A heater 20 heats the gas in the inner tank 11 and takes out the low-temperature fluid 14 by the pressure of the gas. 21
Is a pressure holding valve, which operates so as to maintain the gas pressure in the inner tank 11 at a predetermined value. Reference numeral 22 denotes a safety valve that operates when the gas pressure in the inner tank 11 rises abnormally, and includes the following 23, 26 to 33.

Reference numeral 23 denotes a cylindrical main body fixed to the low-temperature container 13, which is connected to the inner tank 11 via a mounting seat 24 and a pipe 25. Reference numeral 26 denotes a cylindrical valve seat, one end of which is screwed into the main body 23 and the other end of which is formed with a discharge port 26a. Reference numeral 27 denotes a spring receiving seat arranged to be in contact with the valve seat 26, and has a plurality of through holes 27a formed therein. 28 is a seal member arranged between the main body 23 and the valve seat 26,
The inside of the main body 23 is hermetically sealed. 29 is a spring seat 27
The opening 26a of the valve seat 26 can be closed by a valve body having a spring support portion 29a which slidably penetrates through the opening. Numeral 30 is a nut screwed to the support portion 29a, numeral 31 is a spring seat,
Reference numeral 32 denotes a compression spring fitted to the support portion 29a. The compression spring 32 is supported by the spring seat 27 and the spring seat 31 to move the valve body 29 to the valve seat 2.
6 is pressed. Reference numeral 33 denotes a seal member disposed between the valve seat 26 and the valve body 29, and is formed so that ridges 33a and 33b having a quadrangular cross section and existing diagonally are in the axial direction. The seal member 33 is formed of a polymer resin, such as ethylene tetrafluoride, which is cooled when the low-temperature fluid 14 blows out and has flexibility up to a temperature around -200 ° C. One ridge 33a of the seal member 33 is in contact with the valve seat 26 around the discharge port 26a, and the other ridge 33b is in contact with the valve body 29. The ridges 33a and 33b have a radius of, for example, 0.5 mm.
An arc-shaped chamfer of about 5 mm is formed. Holding pressure valve 21
Has the same configuration as the safety valve 22.

Next, the operation will be described. 1 to 3, when the low-temperature fluid 14 is stored in the low-temperature container 13, the low-temperature fluid 14 is injected from an injection port 15 connected to external equipment (not shown). When removing the low-temperature fluid 14 from the low-temperature container 13, the gas of the gasified low-temperature fluid 14 is heated by the heater 20, and the pressure of the gas is applied to the outlet 17.
Remove from In addition, the cryogenic container 13
When the internal pressure increases, the gas of the low-temperature fluid 14 blows out from the pressure holding valve 21 to maintain the gas pressure in the low-temperature container 13 at a predetermined pressure. Further, when the gas pressure in the low temperature container 13 rises abnormally, the safety valve 22 operates to lower the gas pressure in the low temperature container 13. When the gas pressure in the low-temperature container 13 reaches a set predetermined value for both the pressure holding valve 21 and the safety valve 22, each ridge 33 of the seal member 33 is again turned on.
The a and 33b are in contact with the valve seat 26 and the valve body 29, respectively, and operate to stop blowing of gas.

As described above, the seal member 33 is
Since the low-temperature fluid 14 can be prevented from freezing when blown out by being formed of a polymer resin having flexibility up to a temperature around 200 ° C., sufficient airtightness can be achieved even when airtight sealing is performed again. Can be stopped. further,
The sealing member 33 is formed in a quadrilateral shape, and one ridge 33a of the sealing member 33 is brought into contact with the valve seat 26 around the discharge port 26a, and the other ridge 33b is brought into contact with the valve body 29, thereby achieving airtightness. Since the area of the contact surface of the sealing member 33 for stopping is reduced and the surface pressure is increased, the effect of hermetic sealing can be improved.

Embodiment 2 FIG. 4 is a sectional view showing a main part of the second embodiment. In the second embodiment, the seal member 33 in FIG. 2 of the first embodiment is replaced with a seal member 34 described later. Reference numeral 34 denotes a sealing member disposed between the valve seat 26 and the valve element 29, and has ridges 35a, 35b and ridges 36a, 36a,
6b is formed so as to be in the axial direction.
36. The seals 35 and 36 are cooled when the low-temperature fluid 14 blows out, for example, -2.
It is formed of a polymer resin such as ethylene tetrafluoride having flexibility up to a temperature around 00 ° C. A pair of annular seal bodies 35 and 36 are axially opposed to each other, and the opposed ridge portions 35b and 36b are integrated. Then, the ridge 35a at one end in the axial direction of the seal member 34
Is in contact with the valve seat 26 around the discharge port 26a, and the ridge 36a on the other end is in contact with the valve body 29. The ridges 35a and 36a are chamfered in an arc shape having a radius of, for example, about 0.5 mm.

As described above, the sealing member 34 is, for example,
Since the low-temperature fluid 14 can be prevented from freezing when blown out by being formed of a polymer resin having flexibility up to a temperature around 200 ° C., sufficient airtightness can be achieved even when airtight sealing is performed again. Can be stopped. further,
The ridge 35a on the diagonal line of the integrated ridges 35b, 36b is brought into contact with the valve seat 26 around the discharge port 26a, and the ridge 36a is brought into contact with the valve body 29, so that the sealing member 34 is formed. And the effect of hermetic sealing can be further improved.

Embodiment 3 FIG. 5 is a sectional view showing a main part of the third embodiment. In the third embodiment, the seal member 33 in FIG. 2 of the first embodiment is replaced with a seal member 37 described later. Reference numeral 37 denotes a seal member disposed between the valve seat 26 and the valve body 29. The seal member 37 has ridges 38a, 38b and ridges 39a, 39a,
9b is formed of seal bodies 38 and 39 formed in an annular shape so as to be in the axial direction. The seals 38, 3
Numeral 9 is formed of a polymer resin such as ethylene tetrafluoride, which is cooled when the low-temperature fluid 14 blows out and has a flexibility up to a temperature around -200 ° C. A pair of seal bodies 38 and 39 formed in an annular shape are concentrically opposed to each other, and the opposed ridge portions 38c and 39c are integrated. The ridges 38a, 39a on one end in the axial direction of the seal member 37 are in contact with the valve seat 26 around the discharge port 26a, and the ridges 38b, 39b on the other end are in contact with the valve body 29. ing. In addition, each ridgeline part 38a, 38b, 39
For example, a and 39b are chamfered in an arc shape having a radius of about 0.5 mm.

As described above, the sealing member 37 is
Since the low-temperature fluid 14 can be prevented from freezing when blown out by being formed of a polymer resin having flexibility up to a temperature around 200 ° C., sufficient airtightness can be achieved even when airtight sealing is performed again. Can be stopped. further,
By integrating the ridges 38c and 39c, the ridges 38a and 39a at one end in the axial direction are brought into contact with the valve seat 26, and the ridges 38b and 39b at the other end are brought into contact with the valve body 29. The ridges 38a, 39a and the ridges 38b, 39b respectively perform double sealing with respect to the direction of gas leakage, so that the effect of hermetic sealing can be further improved.

Embodiment 4 FIG. 6 is a sectional view showing a main part of the fourth embodiment. In the fourth embodiment, the seal member 33 is replaced with a seal member 40 described later in FIG. 2 of the first embodiment. Reference numeral 40 denotes a seal member disposed between the valve seat 26 and the valve body 29, and is constituted by the following 41 to 46. First, a pair of seal bodies formed of a flexible polymer resin in a ring shape such that ridges 41a and 41b and 42a and 42b each having a quadrangular cross section and present on a diagonal line are in the axial direction. 41 and 42 are opposed in the axial direction, and the opposed ridge portions 41b and 42b are integrated to form a seal body group 43. Further, diagonal ridges 44a and 44b, 45a and 45 are cross-sections having a quadrangular shape.
b, a pair of sealing bodies 44, 45 formed in an annular shape with a polymer resin are axially opposed to each other so that each of them is in the axial direction, and the opposed ridge portions 44b, 45b are integrated to form a seal. A body group 46 is formed. Each of the seals 41, 42, 44, and 45 is cooled when the low-temperature fluid 14 blows out, and is made of, for example, a polymer resin such as ethylene tetrafluoride having flexibility up to a temperature around -200 ° C. is there. Then, the sealing member groups 43 and 46 are arranged concentrically, and a ridge line portion 41c present on the inner peripheral side of the sealing member group 43,
42c and a ridge line portion 4 existing on the outer peripheral side of the seal body group 46.
4c and 45c are integrated. And the sealing member 4
Each ridge line portion 41a, 44a existing on one end side in the axial direction of 0
Is brought into contact with the valve seat 26, and each ridge 42 existing on the other end side is
a and 44a are brought into contact with the valve body 29. Each ridge 4
1a, 42a, 43a, and 45a have, for example, a radius of 0.5 m.
An arc-shaped chamfer of about m is formed.

As described above, the sealing member 40 is
Since the low-temperature fluid 14 can be prevented from freezing when blown out by being formed of a polymer resin having flexibility up to a temperature around 200 ° C., sufficient airtightness can be achieved even when airtight sealing is performed again. Can be stopped. further,
Each ridge line portion 41c and 44c of each seal body group 43, 46, 4
2c and 45c are integrated, respectively, and each ridge 41a,
44a is brought into contact with the valve seat 26, and each ridge 42a, 45a
Is brought into contact with the valve body 29, the flexibility in the pressing direction of the seal member 40 is increased, and the ridge portions 41a, 44a and the ridge portions 42a, 45a respectively double seal against the direction of gas leakage. As a result, the effect of hermetic sealing can be further improved. In the above configuration, each of the seal body groups 4
The same effect can be expected even if resin is filled in the hollow portion surrounded by 3, 46.

[0015]

According to the present invention, since the sealing member is formed of a polymer resin having flexibility even in the temperature range of the low-temperature fluid, it is possible to prevent the low-temperature fluid from freezing when it blows out. When airtight sealing is performed again, sufficient airtight sealing can be performed. In addition, the seal member has a quadrilateral cross section, and one ridge on the diagonal line of the seal member is brought into contact with the valve seat around the discharge port, and the other ridge is brought into contact with the valve body, thereby providing air-tight sealing. Since the area of the contact surface of the sealing member for stopping is reduced and the surface pressure is increased, the effect of hermetic sealing can be improved. Also,
The ridge on one end side of the seal member in which the seal member having a quadrangular cross section is integrated in the axial direction is brought into contact with the valve seat around the discharge port,
By bringing the other end of the seal member into contact with the valve body, the flexibility of the seal member is improved, and the effect of hermetic sealing can be further improved.

Also, a pair of seals are concentrically opposed to each other, and the opposed ridges are integrated to form a seal member. Each ridge at one axial end of the seal is formed around the discharge port. Airtight sealing because each ridge line is double-sealed in the direction of gas leakage by making contact with the valve seat and each ridge line on the other end side with the valve body Can be further improved. Further, a pair of seal members are arranged concentrically, and a ridge portion present on the inner peripheral side of one seal member group and a ridge portion present on the outer peripheral side of the other seal member group are integrated. By forming a seal member, each ridge at one axial end of the seal member is brought into contact with the valve seat around the discharge port, and each ridge at the other end is brought into contact with the valve body. Since the flexibility in the pressing direction of the seal member is increased, and each ridge portion is double-sealed in the direction of gas leakage, the effect of hermetic sealing can be further improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a low-temperature fluid storage device using a low-temperature container pressure adjusting device according to a first embodiment.

FIG. 2 is a cross-sectional view of the low-temperature fluid pressure adjusting device according to the first embodiment.

FIG. 3 is a sectional view showing a main part of FIG. 2;

FIG. 4 is a sectional view showing a main part of the second embodiment.

FIG. 5 is a sectional view showing a main part of a third embodiment.

FIG. 6 is a sectional view showing a main part of a fourth embodiment.

FIG. 7 is a sectional view showing a conventional pressure adjusting device for a cryogenic container.

[Explanation of symbols]

13 low temperature container, 14 low temperature fluid, 26 valve seat, 26a
Discharge port, 29 valve body, 33, 34, 37, 40 Sealing member, 33a, 33b, 35a, 35b, 36a, 3
6b, 38a, 38b, 38c, 39a, 39b, 39
c, 41a, 41b, 41c, 42a, 42b, 42
c, 44a, 44b, 44c, 45a, 45b, 45c
Ridge part, 35, 36, 38, 39, 41, 42, 4
4, 45 Seal body, 43, 46 Seal body group.

Claims (4)

[Claims] When the pressure of a low-temperature container storing a low-temperature fluid exceeds a set pressure, a valve element closing a discharge port on a valve seat side is opened to discharge gas of the low-temperature fluid from the discharge port. In the pressure adjusting device for a cryogenic container, a polymer resin having flexibility even in the temperature range of the cryogenic fluid so that each ridge portion present on a diagonal line in a cross section is in a quadrangular shape in the axial direction. An annular seal member is formed, and the ridge at one axial end of the seal member is brought into contact with the valve seat around the discharge port, and the ridge at the other end is brought into contact with the valve body. A pressure adjusting device for a cryogenic container, wherein the pressure is adjusted. 2. When the pressure of the cryogenic container storing the cryogenic fluid exceeds a set pressure, the valve element closing the discharge port on the valve seat side is opened to discharge the gas of the cryogenic fluid from the discharge port. In the pressure adjusting device of the cryogenic container, the cross section is a quadrilateral so that each ridge portion present on a diagonal line is in the axial direction, so that the polymer resin having flexibility even in the temperature range of the cryogenic fluid is used. A pair of seal bodies formed in an annular shape are axially opposed to each other, and the opposed ridges are integrated to form a seal member, and the ridge at one axial end of the seal member is connected to the discharge port. A pressure adjusting device for a low-temperature container, wherein the pressure-adjusting device is configured to contact the valve seat around the valve member and to contact the ridge portion at the other end with the valve body. 3. When the pressure of the low-temperature container storing the low-temperature fluid exceeds a set pressure, the valve element closing the discharge port on the valve seat side is opened to discharge the low-temperature fluid gas from the discharge port. In the pressure adjusting device of the cryogenic container, the cross section is a quadrilateral so that each ridge portion present on a diagonal line is in the axial direction, so that the polymer resin having flexibility even in the temperature range of the cryogenic fluid is used. A pair of annularly formed seals are concentrically opposed to each other, and the opposed ridges are integrated to form a seal member.The ridges at one axial end of the seal member are connected to the discharge port. A pressure adjusting device for a cryogenic container, wherein the ridge portion at the other end is brought into contact with the valve body. 4. When the pressure of the cryogenic container storing the cryogenic fluid exceeds a set pressure, the valve element closing the discharge port on the valve seat side is opened to discharge the gas of the cryogenic fluid from the discharge port. In the pressure adjusting device of the cryogenic container, the cross section is a quadrilateral so that each ridge portion present on a diagonal line is in the axial direction, so that the polymer resin having flexibility even in the temperature range of the cryogenic fluid is used. A pair of seals formed in an annular shape are axially opposed to each other, the opposed ridges are integrated to form a pair of seals, and the seals are arranged concentrically to one of the seals. A ridge line present on the inner peripheral side of the seal body group and a ridge line present on the outer peripheral side of the other seal body group are integrated to form a seal member, and one end in the axial direction of the seal member is formed. Each ridge portion is brought into contact with the valve seat around the discharge port. A pressure adjusting device for a cryogenic container, wherein the ridge portions on the other end side are brought into contact with the valve body.