Cryogenic storage tank

Abstract

The present invention provides a low-temperature storage tank, comprising: an outer shell, which is placed vertically and is hollow inside; a delivery pipe, which is used to deliver a first low-temperature medium; the delivery pipe extends along the axial direction of the outer shell, is fixedly penetrated through the top of the outer shell and extends into the inner part of the outer shell; a lower gallbladder body, which has a hollow inner cavity for storing the first low-temperature medium, is located inside the outer shell, is fixedly connected to the delivery pipe and communicates with the delivery pipe; an upper gallbladder body is located above the lower gallbladder body at intervals, is sleeved on the delivery pipe and is heat-conductingly connected to the delivery pipe, and the upper gallbladder body is formed with a gallbladder cavity for storing a second low-temperature medium; the boiling point temperature of the second low-temperature medium is not higher than the boiling point temperature of the first low-temperature medium. The upper gallbladder body is closer to the outer side of the outer shell than the lower gallbladder body. The heat outside the storage tank will first be transferred to the upper gallbladder body through the delivery pipe, and the low temperature of the second low-temperature medium inside it will absorb part of the heat, thereby reducing the heat transferred to the lower gallbladder body and increasing the effective storage time of the first low-temperature medium.

Description

Technical Field

[0001] The invention relates to the field of cryogenic liquid containers, and in particular to a cryogenic storage tank. Background Art

[0002] Currently, the market demand for cryogenic containers for containing cryogenic media such as liquid hydrogen has begun to increase. Most companies are still in the R&D and design stage for the manufacture and use of ultra-high vacuum multi-layer insulated cryogenic containers.

[0003] It is particularly difficult to design a small container structure for liquid hydrogen. How to reduce its heat leakage to maintain the state of liquid hydrogen is a pain point that needs to be solved urgently. Specifically, at present, liquid hydrogen containers are generally composed of an outer cylinder and an inner cylinder located in the outer cylinder. The inner cylinder is fixed in the outer cylinder by support structures at both ends. Since the support structure is generally made of metal structure and the support structure is short due to the distance between the inner and outer cylinders, the external heat can be easily transferred to the inner cylinder through the support structure, making the low-temperature medium easy to evaporate. Summary of the invention

[0004] The object of the present invention is to provide a low-temperature storage tank to solve the problems of heat leakage of the supporting structure and difficulty in storing the medium in the low-temperature container in the prior art.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A low-temperature storage tank comprises: an outer shell, which is placed vertically and is hollow inside; a delivery pipe, which is used to deliver a first low-temperature medium; the delivery pipe extends along the axial direction of the outer shell, is fixedly penetrated through the top of the outer shell and extends into the inner part of the outer shell; a lower bladder body, which has a hollow inner cavity for storing the first low-temperature medium, is located inside the outer shell, is fixedly connected to the delivery pipe and communicates with the delivery pipe; an upper bladder body is located above the lower bladder body at an interval, is sleeved on the delivery pipe and is heat-conductingly connected to the delivery pipe, and the upper bladder body is formed with a bladder cavity for storing a second low-temperature medium; the boiling point temperature of the second low-temperature medium is not higher than the boiling point temperature of the first low-temperature medium.

[0007] According to one embodiment of the present invention, the upper gallbladder body comprises a gallbladder shell and a neck tube penetrating the gallbladder shell; the gallbladder cavity is formed between the gallbladder shell and the neck tube; the neck tube is detachably sleeved on the delivery tube and connected and fixed.

[0008] According to one embodiment of the present invention, the upper end of the neck tube is connected and fixed to the tube wall of the delivery tube, and the lower end of the neck tube is a free end; the free end of the neck tube can move axially along the delivery tube when the upper bile body contracts when cooled.

[0009] According to one embodiment of the present invention, the circumferential edge of the upper end of the neck tube is folded toward the inside of the neck tube to form a hook portion, and the opening of the hook portion faces downward; a latching protrusion is provided on the outer peripheral wall of the conveying tube along the circumferential direction, and the latching protrusion is bent and extended upward to form a latching groove with the outer wall of the conveying tube; the latching groove is for the hook portion to extend into, so that the neck tube can be hung on the conveying tube through the hook portion.

[0010] According to one embodiment of the present invention, the neck tube includes a tube body, and an inclined tube segment and a bent tube segment that are bent upward and extended from the upper end of the tube body in sequence; the inclined tube segment gradually deviates radially outward from the axis of the tube body in a direction from bottom to top; the bent tube segment further extends upward from the upper end of the inclined tube segment, and the end of the bent tube segment is bent toward the inside of the inclined tube segment to form the hook portion.

[0011] According to one embodiment of the present invention, the wall thickness of the inclined pipe section is greater than the wall thickness of the pipe body.

[0012] According to one embodiment of the present invention, the cryogenic storage tank further comprises a conductive member; the conductive member is made of a heat-conductive material and is sandwiched between the delivery pipe and the neck pipe.

[0013] According to one embodiment of the present invention, the conductive member includes a heat-conducting tube and a plurality of fins protruding from the outer circumference of the heat-conducting tube and circumferentially spaced apart; the heat-conducting tube is sleeved on the outer circumference of the delivery tube, and the fins elastically abut and support the inner wall of the neck tube.

[0014] According to an embodiment of the present invention, the fin is a sheet-like structure extending along the axial direction of the conductive member, and one end of the fin away from the heat-conducting tube is bent.

[0015] According to an embodiment of the present invention, the gallbladder shell is spherical; the axial direction of the neck tube is consistent with the radial direction of the gallbladder shell.

[0016] According to one embodiment of the present invention, it further includes a bottom support member; the bottom support member is located at the bottom of the lower liner body, and two ends of the bottom support member are respectively connected and fixed to the bottom outer wall of the lower liner body and the inner wall of the outer shell.

[0017] It can be seen from the above technical solution that the low-temperature storage tank provided by the present invention has at least the following advantages and positive effects:

[0018] The delivery pipe extends into the interior of the outer shell and is connected and fixed to the top of the outer shell as a supporting structure to bear the weight of the lower gall body and the upper gall body. The lower gall body mainly stores the first low-temperature medium to be stored, and the upper gall body is sealed with the second low-temperature medium. The boiling point of the second low-temperature medium is not higher than the boiling point of the first low-temperature medium. In addition, the upper gall body is closer to the outside of the outer shell than the lower gall body. Based on the principle of heat conduction, the heat outside the storage tank will first be conducted to the upper gall body through the delivery pipe, and the low temperature of the second low-temperature medium inside it will absorb part of the heat, reducing the heat conducted to the lower gall body, thereby reducing the evaporation of the first low-temperature medium and increasing the effective storage time of the first low-temperature medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the internal structure of a cryogenic storage tank in an embodiment of the present invention.

[0020] Figure 2 Schematic diagram of the structure of the upper gallbladder body in an embodiment of the present invention.

[0021] Figure 3 Schematic diagram of the structure of the lower gallbladder body in an embodiment of the present invention.

[0022] Figure 4 for Figure 1 Enlarged view of point B.

[0023] Figure 5 for Figure 1 AA section view.

[0024] Figure 6 Schematic diagram of the structure of the conductive member in an embodiment of the present invention.

[0025] The following are the descriptions of the reference numerals:

[0026] 1-shell, 10-cylinder, 11-top head, 12-bottom head,

[0027] 2-transmission pipe, 21-card protrusion,

[0028] 3- Lower gallbladder,

[0029] 4-upper gallbladder body, 41-gallbladder shell, 43-neck tube, 431-tube body, 432-inclined tube section, 433-bent tube section, 45-hook part,

[0030] 5-conducting part, 51-heat conducting tube, 52-fin,

[0031] 6-Bottom support. DETAILED DESCRIPTION

[0032] Typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations therein are essentially used for illustration purposes rather than for limiting the present invention.

[0033] This embodiment provides a cryogenic storage tank, which is mainly used to store cryogenic media such as liquid hydrogen.

[0034] The cryogenic storage tank is a vertical storage tank, which includes a delivery pipe extending into the tank, an upper gallbladder body and a lower gallbladder body placed in the tank. Among them, the upper gallbladder body and the lower gallbladder body are both supported by the delivery pipe and are arranged in an upper and lower interval. The lower gallbladder body is connected to the delivery pipe to store the first cryogenic medium (liquid hydrogen), the upper gallbladder body is sleeved on the delivery pipe and is heat-conductingly connected to the delivery pipe, and the upper gallbladder body is formed with a gallbladder cavity for storing the second cryogenic medium. The boiling point temperature of the second cryogenic medium is not higher than the boiling point temperature of the first cryogenic medium. Therefore, the heat outside the storage tank will first be conducted to the upper gallbladder body through the delivery pipe, and the low temperature of the second cryogenic medium inside it will absorb part of the heat, thereby reducing the heat leakage caused by the delivery pipe as a supporting structure, reducing the evaporation of the first cryogenic medium, and increasing the effective storage time of the first cryogenic medium.

[0035] Please refer to Figure 1 , Figure 1 The specific structure of a low-temperature storage tank provided in this embodiment is shown, which mainly includes an outer shell 1, a delivery pipe 2 penetrating the outer shell 1, and a lower tank body 3 and an upper tank body 4 built into the outer shell 1.

[0036] The shell 1 is placed vertically, and its interior is hollow and can be evacuated to form an ultra-high vacuum low-temperature container. The shell 1 includes a cylinder 10 and a top head 11 and a bottom head 12 arranged at the upper and lower ends of the cylinder 10.

[0037] The delivery pipe 2 extends along the axial direction of the shell 1 , is fixedly installed in the top head 11 of the shell 1 and extends into the interior of the shell 1 .

[0038] One end of the delivery pipe 2 exposed outside the shell 1 is used for connecting to an external storage tank, and the inner end thereof is communicated with the lower gallbladder body 3 for delivering the first cryogenic medium to be stored, such as liquid hydrogen, to the lower gallbladder body 3 .

[0039] The delivery pipe 2 is fixed to the top end cap 11 by welding to maintain a vertical state, and is the main supporting structure for supporting the lower gallbladder body 3 and the upper gallbladder body 4.

[0040] The lower liner body 3 is a hollow spherical shell and is located at the inner lower end of the outer shell 1. The top of the lower liner body 3 is welded and fixed to the delivery pipe 2 and communicates with the delivery pipe 2 to receive and store the first low-temperature medium.

[0041] The upper bladder body 4 is spaced above the lower bladder body 3, sleeved on the delivery pipe 2 and thermally connected to the delivery pipe 2. The upper bladder body 4 forms a bladder cavity for storing a second cryogenic medium such as liquid helium, mainly for absorbing external heat.

[0042] The purpose of setting the upper gallbladder body 4 is that the external heat is conducted to the lower gallbladder body 3 at the bottom through the conveying pipe 2, which will increase the temperature of the first low-temperature medium in the spherical container of the lower gallbladder body 3 and affect the storage of the first low-temperature medium in the container. Therefore, the low temperature of the second low-temperature medium in the upper gallbladder body 4 is used to absorb the external temperature and conduct it to the temperature of the lower gallbladder body 3, thereby increasing the storage time of the first low-temperature medium.

[0043] Furthermore, the boiling point of the second low-temperature medium is not higher than the boiling point of the first low-temperature medium.

[0044] In this embodiment, the first cryogenic medium to be stored is liquid hydrogen (abbreviated as LH2), and its boiling point is -253°C. Preferably, the second cryogenic medium is liquid helium (abbreviated as LHe), and its boiling point is -269°C, which is lower than that of liquid hydrogen. In this way, based on the principle of heat conduction, the heat from the outside of the tank will be transferred from the object with high temperature to the object with low temperature along the delivery pipe 2, that is, the liquid helium with low temperature will absorb part of the heat, thereby reducing the heat transferred to the liquid hydrogen, so that the liquid hydrogen can be kept at low temperature for a long time.

[0045] In this embodiment, the outer shell 1 of the storage tank is made of stainless steel, specifically S30408. The upper tank body 4 and the lower tank body 3 are made of the same stainless steel material, both of which are 316L.

[0046] The upper gallbladder body 4 includes a gallbladder shell 41 and a neck tube 43 penetrating the gallbladder shell 41 .

[0047] The gallbladder shell 41 is spherical, and the axial direction of the neck tube 43 is consistent with the radial direction of the gallbladder shell 41. That is, the gallbladder shell 41 and the neck tube 43 are coaxial. A gallbladder cavity is formed between the gallbladder shell 41 and the neck tube 43, and the cross section of the gallbladder cavity includes two hemispherical shapes distributed symmetrically along the axial direction.

[0048] The neck tube 43 is detachably sleeved on the delivery tube 2 and connected and fixed, so as to facilitate installation and maintenance.

[0049] Specifically, the upper end of the neck tube 43 is connected and fixed to the tube wall of the delivery tube 2, and the lower end of the neck tube 43 passes through the delivery tube 2 to be a free end.

[0050] The free end of the neck tube 43 can move axially along the delivery tube 2 when the upper bile body 4 contracts when cooled.

[0051] During use, the delivery tube 2 and the lower gallbladder body 3 are both fixed, and the neck tube 43 can slide axially up and down relative to the fixed delivery tube 2, that is, it can allow the upper gallbladder body 4 connected thereto to effectively shrink along the axial direction under low temperature conditions and release stress under low temperature.

[0052] Please refer to Figure 2 The upper end periphery of the neck tube 43 is folded toward the inside of the neck tube 43 to form a hook portion 45 for hanging and fixing on the conveying tube 2.

[0053] The hook portion 45 is an annular structure, and the opening of the hook portion 45 faces downward, and the cross section of the opening is rectangular.

[0054] Please refer to Figure 3 Correspondingly, a clamping protrusion 21 is protruded circumferentially on the outer peripheral wall of the upper end of the delivery pipe 2, and the clamping protrusion 21 is also an annular structure. The clamping protrusion 21 is bent upward to form a clamping groove with an opening upward between the clamping protrusion 21 and the outer wall of the delivery pipe 2.

[0055] The hook portion 45 is inserted into the slot so that the neck tube 43 can be hung on the delivery tube 2 through the hook portion 45 .

[0056] Please refer to further Figure 4 , Figure 4 for Figure 1 Enlarged view of point B.

[0057] The neck tube 43 includes a tube body 431 and an inclined tube section 432 and a bent tube section 433 which are bent and extended upward from the upper end edge of the tube body 431 in sequence.

[0058] The inclined tube section 432 gradually deviates radially outward from the axis of the tube body 431 from bottom to top, which is manifested in that the inner diameter of the inclined tube section 432 is larger than the inner diameter of the tube body 431 and gradually increases in the upward direction, showing an expansion shape.

[0059] At the same time, the wall thickness of the inclined pipe section 432 is greater than the wall thickness of the pipe body 431, which increases the stress-bearing area. The advantage is that it can ensure the structural strength of the inclined pipeline and avoid breaking due to excessive stress on the connection.

[0060] The cross-sectional shape of one side portion of the inclined pipe section 432 along the axial direction is shuttle-shaped, wherein the wall thickness in the middle is the largest and gradually decreases from the middle to the two ends. The shuttle-shaped structural design can improve the stress state of the structure.

[0061] The bent tube section 433 further extends vertically upward from the upper end of the inclined tube section 432, and the end of the bent tube section 433 is bent toward the inner side of the inclined tube section 432 to form a hook portion 45. The inner diameter of the bent tube section 433 remains unchanged.

[0062] Preferably, the wall thickness of the bent tube section 433 is greater than the thickness of the tube body 431 . Furthermore, the wall thickness of the bent tube section 433 may be equal to or less than the wall thickness of the inclined tube section 432 .

[0063] Further, please refer to Figure 5 and Figure 6 , the cryogenic storage tank further includes a conductive member 5.

[0064] The conducting member 5 is made of a heat-conducting material and is sandwiched between the delivery tube 2 and the neck tube 43. Its purpose is to transfer the heat passing through the delivery tube 2 from the neck tube 43 and the gallbladder shell 41 in sequence to the second low-temperature medium inside the gallbladder shell 41, and most of the heat is absorbed by the second low-temperature medium.

[0065] The conductive member 5 includes a heat-conducting tube 51 and a plurality of fins 52 protruding from the outer circumference of the heat-conducting tube 51 .

[0066] The heat-conducting tube 51 is sleeved on the outer circumference of the delivery tube 2 , and a plurality of fins 52 are arranged at intervals along the circumference of the heat-conducting tube 51 . The fins 52 elastically abut against and support the inner wall of the neck tube 43 .

[0067] In this embodiment, the fin 52 is a sheet-like structure extending along the axial direction of the conductive member 5. The lateral spacing between two adjacent fins 52 is substantially equal. The end of the fin 52 away from the heat-conducting tube 51 is bent, and the end is used to abut against the inner wall of the neck tube 43.

[0068] In this embodiment, the conductive member 5 is entirely made of a heat-conducting material, which may be a metal material such as copper or aluminum alloy, or a non-metallic material made of a composite of other materials.

[0069] In this embodiment, the heat-conducting tube 51 and the fins 52 are brazed together to form the conducting member 5 .

[0070] The conductive member 5 is integrally inserted into the delivery pipe 2 and fixed by brazing, and is pressed into the neck tube 43 of the upper gallbladder body 4 through the elastic fins 52. The conductive member 5 utilizes the characteristic that the thermal conductivity of copper is nearly 1000 times higher than that of stainless steel at low temperatures, and can effectively transfer heat, allowing the second low-temperature medium in the upper gallbladder body 4 to absorb the external heat transferred from the delivery pipe 2, thereby reducing the heat conduction at the connection between the delivery pipe 2 and the lower gallbladder body 3, and increasing the storage time of the first low-temperature medium in the lower gallbladder body 3.

[0071] Please refer back to Figure 1 The low-temperature storage tank provided in this embodiment also includes a bottom support member 6.

[0072] There are multiple bottom support members 6 .

[0073] A plurality of bottom support members 6 are located at the bottom of the lower gallbladder body 3 (close to the bottom end cap 12), and are arranged at intervals along the outer circumference of the lower gallbladder body 3. The bottom support member 6 is horizontal, and its two ends are respectively connected and fixed to the bottom outer wall of the lower gallbladder body 3 and the inner wall of the cylinder 10 of the outer shell 1, so that the bottom of the lower gallbladder body 3 is fixed to the outer shell 1, ensuring that the lower gallbladder body 3 is in a stable state.

[0074] In order to enable those skilled in the art to further understand the various components of the cryogenic storage tank provided in this embodiment, the installation process of each component will be described in detail below.

[0075] The cryogenic storage tank mainly includes an outer shell 1, a delivery pipe 2, an upper gallbladder body 4, a lower gallbladder body 3 and a conductive part 5. First, the conductive part 5 is sleeved and welded to the upper end of the delivery pipe 2. At the same time, the lower gallbladder body 3 is welded to the lower end of the delivery pipe 2. The lower gallbladder body 3 is connected to the delivery pipe 2, and the three are installed together to form a combination. After that, the combination is passed through the neck tube 43 of the upper gallbladder body 4 from bottom to top, so that the hook part 45 on the neck tube 43 corresponds to the clamping protrusion 21 on the delivery pipe 2, so as to realize the connection and fixation between the upper gallbladder body 4 and the delivery pipe 2. Finally, the delivery pipe 2 is extended out of the top head 11 of the outer shell 1 and welded to be fixed.

[0076] The cryogenic storage tank provided in this embodiment is a liquid hydrogen container structure, which has a simple structural design, high economy and strong practicality. This device provides an excellent choice for liquid hydrogen ultra-high vacuum cryogenic containers.

[0077] In summary, the cryogenic storage tank provided by the present invention has at least the following advantages and positive effects:

[0078] The delivery pipe 2 extends into the interior of the outer shell 1 and is connected and fixed to the top of the outer shell 1, so as to serve as a supporting structure to bear the weight of the lower gall body 3 and the upper gall body 4. The lower gall body 3 mainly stores the first low-temperature medium to be stored, and the upper gall body 4 is sealed with the second low-temperature medium. Among them, the boiling point temperature of the second low-temperature medium is not higher than the boiling point temperature of the first low-temperature medium. In addition, the upper gall body 4 is closer to the outside of the outer shell 1 than the lower gall body 3. Based on the principle of heat conduction, the heat outside the storage tank will first be conducted to the upper gall body 4 through the delivery pipe 2, and the low temperature of the second low-temperature medium inside it will absorb part of the heat, reducing the heat conducted to the lower gall body 3, thereby reducing the evaporation of the first low-temperature medium and increasing the effective storage time of the first low-temperature medium.

[0079] Although the present invention has been described with reference to several typical embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Since the present invention can be embodied in a variety of forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims, so all changes and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A cryogenic storage tank, characterized in that: include: The shell is placed vertically and is hollow inside; A delivery pipe, used for delivering a first cryogenic medium; The delivery pipe extends along the axial direction of the shell, is fixedly arranged on the top of the shell and extends into the shell; A lower bladder body, which has a hollow inner cavity for storing the first low-temperature medium, is located inside the outer shell, is fixedly connected to the delivery pipe and communicates with the delivery pipe; The upper bladder body is located above the lower bladder body at a distance, is sleeved on the delivery pipe and is heat-conductingly connected to the delivery pipe, and the upper bladder body is formed with a bladder cavity for storing a second low-temperature medium; the boiling point temperature of the second low-temperature medium is not higher than the boiling point temperature of the first low-temperature medium; The upper gallbladder body comprises a gallbladder shell and a neck tube penetrating the gallbladder shell; the gallbladder cavity is formed between the gallbladder shell and the neck tube; the neck tube is detachably sleeved on the delivery tube and connected and fixed; The upper end of the neck tube is connected and fixed to the tube wall of the delivery tube, and the lower end of the neck tube is a free end; the free end of the neck tube can move axially along the delivery tube when the upper gallbladder body contracts when it is cooled.

2. The cryogenic storage tank according to claim 1, characterized in that: The upper end periphery of the neck tube is folded toward the inside of the neck tube to form a hook portion, and the opening of the hook portion faces downward; A latching protrusion is circumferentially protruding from the outer wall of the delivery tube, and the latching protrusion is bent upward to form a latching groove with the outer wall of the delivery tube; the latching groove is for the hook part to extend into, so that the neck tube can be hung on the delivery tube through the hook part.

3. The cryogenic storage tank according to claim 2, characterized in that: The neck tube comprises a tube body, and an inclined tube section and a bent tube section which are bent and extended upward from the upper end of the tube body in sequence; The inclined tube section gradually deviates radially outward from the axis of the tube body in a direction from bottom to top; the bent tube section further extends upward from the upper end of the inclined tube section, and the end of the bent tube section is bent toward the inside of the inclined tube section to form the hook portion.

4. The cryogenic storage tank according to claim 3, characterized in that: The wall thickness of the inclined pipe section is greater than the wall thickness of the pipe body.

5. The cryogenic storage tank according to claim 1, characterized in that: The low-temperature storage tank also includes a conductive member; the conductive member is made of a heat-conductive material and is sandwiched between the delivery pipe and the neck pipe.

6. The cryogenic storage tank according to claim 5, characterized in that: The conducting member comprises a heat-conducting tube and a plurality of fins protruding from the outer circumference of the heat-conducting tube and spaced circumferentially; the heat-conducting tube is sleeved on the outer circumference of the delivery tube, and the fins elastically abut and support the inner wall of the neck tube.

7. The cryogenic storage tank according to claim 6, characterized in that: The fin is a sheet-like structure extending along the axial direction of the conductive member, and one end of the fin away from the heat-conducting tube is bent.

8. The cryogenic storage tank according to claim 1, characterized in that: The gallbladder shell is spherical; the axial direction of the neck tube is consistent with the radial direction of the gallbladder shell.

9. The cryogenic storage tank according to claim 1, characterized in that: Also included is a bottom support member; The bottom support member is located at the bottom of the lower liner body, and two ends of the bottom support member are respectively connected and fixed to the bottom outer wall of the lower liner body and the inner wall of the outer shell.

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