Cryogenic container

Abstract

To protect an exterior of a stationary tank or an exterior of a movable semitrailer from overpressure in a space between walls.SOLUTION: A cryogenic container 1 comprises an inner wall 2 defining a storage volume, and an outer wall 3 having a space 4 between vacuum insulation walls, and disposed around the inner wall. A pressure-control valve 5 configured so as to discharge excessive pressure in the space between the walls is disposed on the outer wall. The pressure-control valve can move between a first position and a second position thereof, and is guided in a vertical direction via a guide system located inside an opening. A cap is configured to be moved toward the second position by overpressure greater than a threshold determined in the space between the walls, and to be returned toward the first position by gravity when the overpressure greater than the determined threshold is stopped.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to cryogenic containers, and particularly to tanks for storing cryogenic fluids.

[0002] More specifically, the present invention relates to a cryogenic container, particularly a tank for storing cryogenic fluids, comprising an inner wall defining a storage volume and an outer wall disposed around the inner wall with a vacuum insulation wall space therebetween, wherein the outer wall is provided with an overpressure valve configured to discharge excess pressure in the wall space, and the overpressure valve includes a cap attached so as to be movable between a first position closing an opening communicating with the wall space and a second position opening the opening.

[0003] In particular, the present invention relates to an overpressure valve for any cryogenic container or cryogenic device (stationary or movable), and particularly to an overpressure valve for a tank for storing flammable cryogenic liquids (particularly hydrogen).

Background Art

[0004] In particular, the present invention makes it possible to protect the exterior (wall) of a stationary tank or the exterior (wall) of a movable semi-trailer from overpressure in the wall space (between an inner wall forming an inner tank and a wall forming the exterior).

[0005] Specifically, in the case of a fault or overpressure in the wall space, it is necessary to be able to discharge this overpressure and then avoid pumping ambient air when returning to a vacuum again.

[0006] In particular, in the case of leakage of flammable liquids, it is important to avoid generating an explosive gas volume.

[0007] However, known overpressure valves (generally called "vacuum plugs") are generally difficult to handle, expensive, and unsatisfactory. In particular, their automatic opening and closing mechanisms are large and / or not very reliable. [Overview of the project]

[0008] The object of the present invention is to overcome all or some of the above-mentioned drawbacks of the prior art.

[0009] For this purpose, otherwise according to the comprehensive definition given in the above preface, the container according to the present invention is characterized in that the cap is movable and guided vertically between a first position and a second position via a guide system located inside the opening, and the cap is configured to move toward the second position when an overpressure greater than a determined threshold in the interwall space is exceeded, and to return toward the first position by gravity when the overpressure greater than the aforementioned determined threshold is exceeded.

[0010] Furthermore, embodiments of the present invention may have one or more of the following features: - The cap and / or opening is provided with a sealing member such as a seal to ensure that the opening is tightly closed in its first position. - The sealing member is compressed between the wall defining the opening and the cap at its first position. - The guide system comprises a shaft fixed to the cap and a guide for the shaft fixedly mounted within the opening. - The shaft guide comprises a tubular section that slides to receive the shaft, and the aforementioned shaft guide is held within the opening via a pair of support arms fastened to a wall defining the opening. - The shaft guides the shaft along a vertical length equal to at least twice the transverse dimension of the shaft. - The shaft includes a transverse blocking member that forms a stop portion that limits the vertical position of the bottom of the shaft. - The cap and / or guide system is equipped with a flyweight to bias the cap toward a first position by gravity. - The fly weight is fixed to the shaft. - The flyweight is located at the lower end of the shaft and forms a stopper that limits the vertical position of the cap's top. - The opening is defined by a tubular wall section connected to the outer wall. - The tubular wall section is vertical and connected to the side (flank) of the outer wall via a bend. - The end of the vertical tubular wall section is located at the same height as or below the upper end of the outer wall. - The device is a cryogenic fluid storage tank, and its inner wall defines the storage volume for the fluid. - The device is a cold box for cryogenic equipment that houses cryogenic components.

[0011] The present invention may also relate to any alternative apparatus or method comprising any combination of the above or below features of the claims.

[0012] Other specific features and advantages will become apparent by reading the following description, which is given with reference to the drawings. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 shows schematic and partial views of a vertical and longitudinal cross-section illustrating an example of a container that implements the present invention. [Figure 2] Figure 2 shows a schematic and partial view of the details of the overpressure valve of the vessel in Figure 1 in a vertical cross-section. [Figure 3] Figure 3 shows a schematic, partial, and transparent perspective view of the valve details. [Figure 4] Figure 4 shows a schematic and partial perspective view of a half-section of the overpressure valve mentioned above. [Modes for carrying out the invention]

[0014] Figure 1 shows a cryogenic container composed of a cryogenic fluid storage tank. This tank includes an inner wall or interior 2, for example, of a cylindrical shape that defines a storage volume for the fluid, and an outer wall 3 disposed with a vacuum insulation wall space 4 around the inner wall 2.

[0015] The tank conventionally includes a valve / a circuit provided with a plurality of valves, which is not described in detail for the sake of brevity.

[0016] The outer wall 3 includes an opening 7 that is closed by an overpressure valve 5 configured to discharge excess pressure in the wall space 4 in case of a malfunction. The opening 7 is defined, for example, by a tubular wall portion 13 connected to the outer wall 3.

[0017] As illustrated, the overpressure valve 5 can be formed at the end of the tubular wall portion 13, which is vertical in the usage configuration and is connected, for example, via a bend, to the side surface of the outer wall 3.

[0018] The overpressure valve 5 includes, for example, a disk-shaped cap 6, which is attached so as to be movable with respect to a circular opening 7 communicating with the wall space 4.

[0019] The cap 6 is movable between a first position closing the opening 7 and a second position opening the opening 7.

[0020] More precisely, the cap 6 is attached and vertically guided to be movable between its first and second positions via guide systems 9, 10 located inside the opening 7 (or the tubular portion 13).

[0021] The cap 6 is configured to be freely moved towards the second position by an overpressure greater than a determined threshold value in the wall space 4. That is, when the pressure in the wall space exceeds the determined threshold value, this pressure lifts the cap to open the opening 7.

[0022] Similarly, once this overpressure subsides, cap 6 automatically returns to its first position due to gravity.

[0023] A sealing member 8, such as an O-ring seal, may be provided on the edge of the opening 7 to ensure that the opening 7 is tightly closed. Thus, the seal 8 is compressed when the cap 6 is in its first position, creating a closure under vacuum.

[0024] In the illustrated example, the guide system comprises a shaft 10 fixed to the cap 6 and a guide 9 for the shaft 10 mounted within the opening 7. The guide 9 is preferably fixed to the opening. For example, the upper end of the shaft 10 is screwed into the cap 6.

[0025] The shaft guide 9 may have a tubular section that receives the shaft 10 in a vertical sliding manner. The guide 9 is held within the opening 7 (preferably centered in the tubular section 13) via, for example, a pair of support arms 11 fastened to a wall defining the opening 7. In the example illustrated in Figure 3, for example, three support arms 11 are provided around the guide, distributed at 120-degree angles. One end of each arm may be welded to the guide 9, and the other end of each arm may be welded to the inner wall of the tubular section 13.

[0026] The shaft 10 is, for example, cylindrical in shape with a disc-shaped cross-section. The guide 9 is preferably sized to guide the shaft 10 along a vertical length equal to at least twice the transverse dimension (diameter) of the shaft 10.

[0027] Preferably, a flyweight 12 is provided to contribute to closing the cap 6. Preferably, the flyweight 12 is located at the height of the second lower end of the shaft 10. The flyweight 12 and / or the shaft may form projections that abut against the guide 9 (or similar) to limit the top position of the cap 6 and prevent it from detaching from the orifice and the container.

[0028] As illustrated in Figure 4, the shaft 10 may include a transverse blocking member 14 that forms a stopper limiting the vertical position of the bottom of the shaft 10. This blocking member 14, which may include a (preferably elastic) pin mounted through the shaft 10, prevents the shaft 10 from falling into the inter-wall space 4 if the cap 6 comes off. Any other transverse blocking member is conceivable.

[0029] Therefore, the guide, return, and mounting mechanisms for cover 6 can be fully integrated within the orifice 7.

[0030] As illustrated in Figure 1, in particular, in the case of a movable cryogenic horizontal tank (semi-trailer or similar), the end of the vertical tubular wall section 13 is located at the same height as or below the upper end of the outer wall 3.

[0031] Naturally, the present invention can also be applied to other containers, particularly cold boxes in cryogenic (e.g., liquefaction) facilities. The following is a direct reproduction of the claims as originally filed. [1] A cryogenic container (1), more particularly a tank for storing cryogenic fluids, comprising an inner wall (2) defining the storage volume and an outer wall (3) arranged around the inner wall (2) with a vacuum-insulated inter-wall space (4), The outer wall (3) is provided with an overpressure valve (5) configured to discharge excess pressure in the inter-wall space (4). The overpressure valve (5) includes a cap (6) attached to an opening (7) that communicates with the wall space (4), such that the cap (6) is movable between a first position that closes the opening (7) and a second position that opens the opening (7). The cap (6) is movable between a first position and a second position and is guided vertically via a guide system (9, 10) located inside the opening (7). In a cryogenic container (1), the cap (6) is configured to move toward the second position when an overpressure greater than a determined threshold in the inter-wall space (4) is exceeded, and to return toward the first position by gravity when the overpressure greater than the determined threshold is eliminated. A cryogenic container characterized in that the guide system (9, 10) comprises a shaft (10) fixed to the cap (6) and a guide (9) for the shaft (10) installed inside the opening (7). [2] The cryogenic container according to [1], characterized in that the cap (6) and / or the opening (7) are provided with a sealing member (8) such as a seal that ensures the opening (7) is tightly closed in its first position. [3] The cryogenic container according to [2], characterized in that the sealing member (8) is compressed between the wall defining the opening and the cap (6) at its first position. [4] The cryogenic container according to any one of [1] to [3], characterized in that the guide (9) of the shaft (10) has a tubular portion that slidably receives the shaft (10), and the guide (9) of the shaft (10) is held in the opening via a pair of support arms (11) fastened to a wall defining the opening (7). [5] The cryogenic vessel according to any one of [1] to [4], characterized in that the guide (9) of the shaft (10) guides the shaft (10) along a vertical length equal to at least twice the transverse dimension of the shaft (10). [6] The cryogenic container according to any one of [1] to [5], characterized in that the shaft (10) is provided with a transverse blocking member (14) that forms a stop portion that limits the vertical position of the bottom of the shaft (10). [7] The cryogenic vessel according to any one of [1] to [6], characterized in that the cap (6) and / or the guide system (9, 10) comprises a flyweight (12) to bias the cap (6) toward the first position by gravity. [8] The cryogenic container according to [7], characterized in that the flyweight (12) is fixed to the shaft (10). [9] The cryogenic container according to [8], characterized in that the flyweight (12) is located at the lower end of the shaft (10) and forms a stopper that limits the vertical position of the top of the cap (6).

[10] The cryogenic container according to any one of [1] to [9], characterized in that the opening (7) is defined by a tubular wall portion (13) connected to the outer wall (3).

[11] The cryogenic container according to any one of [1] to

[10] , characterized in that the tubular wall portion (13) is vertical and connected to the side surface of the outer wall (3) via a bend.

[12] The cryogenic container according to

[11] , characterized in that the end portion of the vertical tubular wall portion (13) is located at the same height as or below the upper end portion of the outer wall (3).

[13] A cryogenic container according to any one of [1] to

[12] , characterized in that the cryogenic container (1) is a tank for storing cryogenic fluid, and the inner wall (2) defines the storage volume for the cryogenic fluid.

[14] A cryogenic container according to any one of [1] to

[13] , characterized in that the cryogenic container (1) is a cold box of a cryogenic facility that houses cryogenic components.

Claims

1. A cryogenic container (1), particularly a tank for storing cryogenic fluids, comprising an inner wall (2) defining the storage volume and an outer wall (3) arranged around the inner wall (2) with a vacuum-insulated inter-wall space (4), The outer wall (3) is provided with an overpressure valve (5) configured to discharge excess pressure in the inter-wall space (4). The overpressure valve (5) includes a cap (6) attached to an opening (7) that communicates with the wall space (4), such that the cap (6) is movable between a first position that closes the opening (7) and a second position that opens the opening (7). The cap (6) is movable between a first position and a second position and is guided vertically via a guide system (9, 10) located inside the opening (7). In a cryogenic container (1), the cap (6) is configured to move toward the second position when an overpressure greater than a determined threshold in the inter-wall space (4) is exceeded, and to return toward the first position by gravity when the overpressure greater than the determined threshold is eliminated. A cryogenic container characterized in that the guide system (9, 10) comprises a shaft (10) fixed to the cap (6) and a guide (9) for the shaft (10) installed inside the opening (7).

2. The cryogenic container according to claim 1, characterized in that the cap (6) and / or the opening (7) are provided with a sealing member (8) such as a seal that ensures the opening (7) is tightly closed in its first position.

3. The cryogenic container according to claim 2, characterized in that the sealing member (8) is compressed between the wall defining the opening and the cap (6) at its first position.

4. The cryogenic container according to any one of claims 1 to 3, characterized in that the guide (9) of the shaft (10) has a tubular portion that slidably receives the shaft (10), and the guide (9) of the shaft (10) is held in the opening via a pair of support arms (11) fastened to a wall defining the opening (7).

5. The cryogenic container according to any one of claims 1 to 3, characterized in that the guide (9) of the shaft (10) guides the shaft (10) along a vertical length equal to at least twice the transverse dimension of the shaft (10).

6. The cryogenic container according to any one of claims 1 to 3, characterized in that the shaft (10) is provided with a transverse blocking member (14) that forms a stop portion that limits the vertical position of the bottom of the shaft (10).

7. The cryogenic container according to any one of claims 1 to 3, characterized in that the cap (6) and / or the guide system (9, 10) are provided with a flyweight (12) to bias the cap (6) toward the first position by gravity.

8. The cryogenic container according to claim 7, characterized in that the flyweight (12) is fixed to the shaft (10).

9. The cryogenic container according to claim 8, characterized in that the flyweight (12) is located at the lower end of the shaft (10) and forms a stopper that limits the vertical position of the top of the cap (6).

10. The cryogenic container according to any one of claims 1 to 3, characterized in that the opening (7) is defined by a tubular wall portion (13) connected to the outer wall (3).

11. The cryogenic container according to claim 10, characterized in that the tubular wall portion (13) is vertical and connected to the side surface of the outer wall (3) via a bend.

12. The cryogenic container according to claim 11, characterized in that the end portion of the vertical tubular wall portion (13) is located at the same height as or below the upper end portion of the outer wall (3).

13. A cryogenic container according to any one of claims 1 to 3, characterized in that the cryogenic container (1) is a tank for storing cryogenic fluid, and the inner wall (2) defines the storage volume for the cryogenic fluid.

14. A cryogenic container according to any one of claims 1 to 3, characterized in that the cryogenic container (1) is a cold box of a cryogenic facility that houses cryogenic components.

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