CN215215176U

CN215215176U - Low-temperature joint

Info

Publication number: CN215215176U
Application number: CN202121122413.9U
Authority: CN
Inventors: 杨少柒; 潘薇; 谢秀娟; 薛瑞; 龚领会
Original assignee: Technical Institute of Physics and Chemistry of CAS
Current assignee: Technical Institute of Physics and Chemistry of CAS
Priority date: 2021-05-24
Filing date: 2021-05-24
Publication date: 2021-12-17
Anticipated expiration: 2031-05-24

Abstract

The utility model is suitable for a liquid hydrogen field of carrying discloses low temperature joint, including adiabatic pipe, core and fastener, adiabatic pipe includes the same first part of structure and second part, first part includes first inner tube, first outer tube and sets up the flange in the one end of first part, the flange outwards extends from first inner tube, and protrusion first outer tube, the core includes two guide blocks, sealing block, second inner tube and second outer tube, two guide blocks one-to-one are installed on the both sides end of second outer tube, the sealing block ring is established in second outer tube periphery, be formed with the second vacuum chamber between second inner tube and the second outer tube, the both sides end of second inner tube is provided with the core head that is used for sealing the second vacuum chamber, the core assembly is in adiabatic pipe, the flange of the first part of adiabatic pipe and the flange of second part clamp are in sealing block both sides, first part and second part pass through the fastener and connect, the low-temperature joint can realize the quick connection, low heat leakage and low loss of the liquid hydrogen transmission pipeline.

Description

Low-temperature joint

Technical Field

The utility model relates to a liquid hydrogen carries the field, especially relates to a low temperature joint.

Background

Liquid hydrogen is one of the important forms of hydrogen energy utilization. The liquid hydrogen refueling station is a facility for effectively utilizing liquid hydrogen and can provide fuel for a hydrogen fuel automobile. In a mature process abroad, gaseous hydrogen is generally reduced to 20K for liquefaction in a liquid hydrogen plant, is conveyed to a liquid hydrogen tanker through a cryogenic transfer pipeline, is then conveyed to a hydrogenation station through the liquid hydrogen tanker, and is conveyed to a liquid hydrogen storage tank in the station through the cryogenic transfer pipeline again for storage. The saturated liquid hydrogen temperature under atmospheric pressure is 20.23K (-252.92 deg.C), which is far lower than normal temperature, and belongs to cryogenic fluid, and the transportation, storage and transportation process must be insulated and heat preserved to reduce loss.

The low-temperature joint is indispensable equipment for transmitting liquid hydrogen between different equipment, and the disassembly convenience and the low heat leakage performance of the low-temperature joint are the keys for reducing the disassembly loss of the liquid hydrogen when the disassembly is time-consuming. Currently available cryogenic joints include flanged direct connection forms and BNC joint forms. In the flange direct connection type low-temperature joint, the flange is directly contacted with the low-temperature fluid, so that heat leakage is very large, and the joint is seriously frosted. The low temperature joint in the BNC joint form can reduce heat leakage, but the two ends of the infusion tube need to be welded with the male and female heads of the BNC joint, the structure is complex, and the installation is special.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a low temperature joint, it is convenient to dismantle, can realize the high-speed joint of liquid hydrogen transmission pipeline and realize that low heat leak, low loss liquid hydrogen are carried.

In order to achieve the above purpose, the utility model provides a scheme is:

a low-temperature joint comprises a heat insulation pipe, a core body and a fastener, wherein the heat insulation pipe comprises a first component and a second component, the first component comprises a first inner pipe and a first outer pipe which are coaxially arranged and a flange arranged at one end of the first component, the flange extends outwards from the first inner pipe and protrudes out of the first outer pipe, the structure of the second component is the same as that of the first component, the core body comprises two guide blocks, a sealing block and a second inner pipe and a second outer pipe which are coaxially arranged, the two guide blocks are correspondingly arranged at the two side ends of the second outer pipe one by one, the sealing block is annularly arranged at the periphery of the second outer pipe, a second vacuum cavity is formed between the second inner pipe and the second outer pipe, and core body end sockets extending from the second inner pipe to the guide blocks are arranged at the two side ends of the second inner pipe, the core head is used for sealing a second vacuum cavity, the core body is assembled in the heat insulation pipe, the flange of the first component and the flange of the second component are clamped on two sides of the sealing block, the first component and the second component are connected through the fastener, and the sealing block is respectively connected with the flange of the first component and the flange of the second component in a sealing mode.

Preferably, the sealing block and the flange of the first component and the sealing block and the flange of the second component are sealed through an inner sealing ring and an outer sealing ring, two sealing grooves are formed in the side face, in contact with the flange, of the sealing block, the inner sealing ring is installed on one of the sealing rings, and the outer sealing ring is installed on the other sealing ring.

Preferably, a first vacuum chamber is formed between the first inner tube and the first outer tube.

Preferably, the side wall of the first inner pipe opposite to the first outer pipe is wrapped with an insulating wrapping layer.

Preferably, the flanges are welded to the first inner pipe and the first outer pipe, respectively, as a single body.

Preferably, the sealing block, the second inner pipe, the second outer pipe and the core body end socket are welded into a whole.

Preferably, the tail ends of the two sides of the second outer pipe are provided with step positions, and the two guide blocks are correspondingly arranged on the step positions one by one.

Preferably, the guide block is an annular body made of polytetrafluoroethylene.

Preferably, the side wall of the second inner pipe opposite to the second outer pipe is wrapped with an insulating wrapping layer.

Preferably, the second vacuum chamber is filled with a porous material.

The utility model provides a low temperature joint inserts the first part of heat-insulating pipe with the core that assembles when assembling, and under the guide of guide block, the core inserts first part approximately concentrically until the sealing block contacts the flange; then, the second part of the heat-insulating pipe is sleeved on the other side of the core body, under the guide of the guide block, the flange of the second part is in contact with the other side of the sealing block, and finally the flanges on the two sides are locked by the fastening piece, so that the assembly of the low-temperature joint is completed, the assembly is convenient and fast, the disassembly is convenient, and the quick connection of the liquid hydrogen transmission pipeline can be realized. In addition, the heat insulation pipe and the core body of the low-temperature joint both adopt double-layer pipe bodies, so that the low-temperature joint has excellent heat insulation performance and can realize low-heat-leakage and low-loss liquid hydrogen transportation. Furthermore, the utility model discloses a low temperature joint sets up the guide block so that the core inserts the first part and the second part of adiabatic pipe approximately concentrically at the both sides end of second outer pipe, and then can improve the assembly precision.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a schematic structural view of a cryogenic connector according to a first embodiment of the present invention;

FIG. 2 is a schematic structural view of a cryogenic connector according to a second embodiment of the present invention;

FIG. 3 is a schematic structural view of a cryogenic connector according to a third embodiment of the present invention;

fig. 4 is a schematic structural view of a cryogenic coupling according to a fourth embodiment of the present invention.

The reference numbers illustrate:

1. a heat-insulating pipe; 11. a flange; 12. a first outer tube; 13. a first inner tube; 14. a first vacuum chamber; 15. a heat-insulating bundling layer;

2. a core body; 21. a guide block; 22. a second outer tube; 23. an inner seal ring; 24. an outer sealing ring; 25. a sealing block; 26. sealing a core body end; 27. a second inner tube; 28. a second vacuum chamber; 29. a gap;

3. a fastener.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that all the directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

It will also be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit ly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

As shown in fig. 1 to 4, which are cryogenic couplings according to an embodiment of the present invention, low heat leakage and low liquid hydrogen transportation can be achieved.

Referring to fig. 1 to 4, a cryogenic coupling according to an embodiment of the present invention includes a thermal insulation pipe 1, a core 2 and a fastening member 3, the thermal insulation pipe 1 is a double-layered thermal insulation pipe including a first member and a second member, the first member includes a first inner pipe 13 and a first outer pipe 12 coaxially disposed, and a flange 11 disposed at one end of the first member, the flange 11 extends outward from the first inner pipe 13 and protrudes out of the first outer pipe 12, that is, the flange 11 is an annular structure capable of connecting the first inner pipe 13 and the first outer pipe 12 into a whole, the second member has a structure identical to that of the first member, the core 2 includes two guide blocks 21, a sealing block 25, and a second inner pipe 27 and a second outer pipe 22 coaxially disposed, the two guide blocks 21 are installed at both ends of the second outer pipe 22 in one-to-one correspondence, the sealing block 25 is annularly disposed at the periphery of the second outer pipe 22, a second vacuum chamber 28 is formed between the second inner pipe 27 and the second outer pipe 22, the gap of the second vacuum chamber 28 is determined according to the design, the core body end sockets 26 extending from the second inner tube 27 to the guide block 21 are arranged at the tail ends of two sides of the second inner tube 27, the core body end sockets 26 are used for sealing the second vacuum chamber 28, a hydrogen gas column is formed in the second vacuum chamber 28, the heat conduction performance of the second inner tube 27 is reduced, and the heat insulation effect is further improved. The core body 2 is fitted in the thermal insulation piping 1, and the flange 11 of the first member and the flange 11 of the second member of the thermal insulation piping 1 are clamped on both sides of the sealing block 25, the first member and the second member are connected by the fastening member 3, and the sealing block 25 is sealingly connected with the flange 11 of the first member and the flange 11 of the second member, respectively.

It should be noted that, the first outer tube 12 and the first inner tube 13 may be made of a metal hard tube, such as stainless steel with poor thermal conductivity, or may be made of a part of a metal hose, that is, a joint is changed into a metal hose, or may be made of a whole metal hose, and the joint is lined with a metal hard tube. The outer diameter and the wall thickness of the first inner tube 13 are designed in accordance with the pressure and the flow rate. The diameter and wall thickness of the first outer tube 12 are selected based on the heat leak requirement per unit length, the thickness of the insulating wrap 15 and the gap design of the second vacuum chamber 28. The flange 11 has its inside and outside diameter determined by the first outer pipe 12 and the first inner pipe 13, and the thickness and the number of bolt holes are checked according to the liquid hydrogen pressure.

Except for the core heads 26 at both ends, there is no contact between the second inner tube 27 and the second outer tube 22. The second inner pipe 27 is a metal hard pipe, such as a stainless steel pipe, the second outer pipe 22 is a metal hard pipe, the outer diameter of the metal hard pipe is matched with the first inner pipe 13 in the heat insulation pipe 1, a gap 29 of not less than 1mm is generally reserved, and the wall thickness meets the requirement of liquid hydrogen pressure, namely the thickness of the guide block 21 is larger than that of the second outer pipe 22. The guide block 21 is separated from the other parts of the core body 2, the inner diameter of the guide block is consistent with the outer diameter of the end socket of the second outer pipe 22, the outer diameter of the guide block is consistent with the inner diameter of the second inner pipe 27, the guide block 21 is made of polytetrafluoroethylene or other low-temperature materials, is installed at the tail end of the second outer pipe 22, and is provided with a through hole or a groove along the axial direction. The outer diameter of the sealing block 25 is matched with the flange 11, the outer diameter of the sealing block can be smaller than the minimum value of the distance between a bolt hole of the flange 11 and the center of the flange 11, the outer diameter of the sealing block can also be consistent with the outer diameter of the flange 11, through holes with the same size are processed on the sealing block 25 for bolts to pass through, and the wall thickness of the sealing block 25 is determined by pressure checking.

It will be appreciated that the portion of the sealing block 25 projecting beyond the second outer tube 22 may be flush with the portion of the flange 11 projecting beyond the first outer tube 12 (as shown in figure 1), with the fastener 3 being secured through the flange 11 of the first part, the sealing block 25 and the flange 11 of the second part. There is a height difference between the sealing block 25 and the flange 11 (as shown in fig. 2), and the fastening member 3 is fixed after passing through the flange 11 of the first member and the flange 11 of the second member.

The embodiment of the utility model provides a low temperature joint inserts the first part of heat-insulating pipe 1 with assembled core 2 when assembling, and under the guide of guide block 21, core 2 inserts first part approximately concentrically, until seal block 25 contacts flange 11; then, the second part of the heat insulation pipe 1 is sleeved on the other side of the core body 2, under the guide of the guide block 21, the flange 11 of the second part is in contact with the other side of the sealing block 25, and finally the flanges 11 on the two sides are locked by the fastening piece 3, so that the assembly of the low-temperature joint is completed, the assembly is convenient, the disassembly is convenient, and the quick connection of the liquid hydrogen transmission pipeline can be realized. In addition, the heat insulation pipe 1 and the core body 2 of the low-temperature joint both adopt double-layer pipe bodies, have excellent heat insulation performance, and can realize low heat leakage and low loss liquid hydrogen transportation. Furthermore, the cryogenic coupling of the embodiment of the present invention provides the guide blocks 21 at both ends of the second outer pipe 22 so that the core 2 is inserted approximately concentrically into the first member and the second member of the thermal insulation pipe 1, and thus the assembly accuracy can be improved.

Optionally, the sealing block 25 and the flange 11 are sealed by a sealing ring, the number of the sealing rings may be set as required, and the installation manner of the sealing rings also needs to be set as required. As shown in fig. 1 and 2, two seal grooves are used between the single-side seal block 25 and the flange 11, two seal grooves are provided on the side surface of the seal block 25 contacting the flange 11 for installing the inner seal ring 23 and the outer seal ring 24, and the inner seal ring 23 and the outer seal ring 24 may be rubber O rings or other sealing gaskets. It is understood that the sealing groove may be provided on the sealing block 25 or on the flange 11, as shown in fig. 3, and two sealing grooves are provided on the flange 11. As shown in fig. 4, a sealing groove is used between the sealing block 25 and the flange 11 on one side, and a sealing groove is provided on the side of the flange 11 contacting the sealing block 25 for installing a sealing ring, which may be a rubber O-ring or other sealing gasket.

Preferably, a first vacuum chamber 14 is formed between the first inner tube 13 and the first outer tube 12, and the low temperature joint of the embodiment of the present invention can reduce heat leakage from the first inner tube 13 to the first outer tube 12 by providing the first vacuum chamber 14.

Preferably, the side wall (outer surface) of the first inner pipe 13 opposite to the first outer pipe 12 is wrapped with a heat insulation wrapping layer 15, and the heat insulation wrapping layer 15 can further improve the heat insulation effect.

It will be appreciated that the outer surface of the first inner pipe section 13 may or may not be wrapped with insulation.

Optionally, the flange 11 is welded with the first inner pipe 13 and the first outer pipe 12 as a whole, so as to further improve the sealing performance and reduce heat leakage.

Preferably, the second vacuum chamber 28 can be filled with a small amount of porous material such as activated carbon for absorbing heat.

Preferably, the sealing block 25, the second inner pipe 27, the second outer pipe 22 and the core head 26 are welded into a whole, which is beneficial to improving the assembly efficiency of the low-temperature joint.

Preferably, the ends of the two sides of the second outer tube 27 are provided with step positions (not shown), and the two guide blocks 21 are correspondingly mounted on the step positions one by one, so that the mounting manner is simple and reliable.

Preferably, the side wall (outer surface) of the second inner pipe 27 opposite to the second outer pipe 22 is wrapped with the heat insulation wrapping layer 15, the outer surface of the heat insulation material is not in contact with the inner surface of the second outer pipe 22 during wrapping, and the heat insulation wrapping layer 15 is arranged to further improve the heat insulation effect.

It will be appreciated that the outer surface of the second inner pipe section 27 may or may not be wrapped with insulation.

The utility model discloses thermal resistance is big on the whole heat transfer path of low temperature joint, and it is little to leak heat, can effectively less liquid hydrogen loss.

The utility model discloses low temperature joint's theory of operation as follows: the first vacuum chamber 14 and the second vacuum chamber 28 are evacuated to a predetermined vacuum and then sealed; after the guide blocks 21 are installed at both ends of the second outer pipe 22 and the sealing rings are installed in the sealing grooves of the sealing blocks 25 (different installation methods of the sealing rings are applicable to different installation methods, which are only exemplified herein), the assembled core body 2 is inserted into the first component of the thermal insulation pipe 1, and the core body 2 is inserted into the first component approximately concentrically under the guidance of the guide blocks 21 until the sealing blocks 25 contact the flange 11; then, the second member of the thermal insulation piping 1 is fitted into the other side of the core body 2, and the flange 11 of the second member is brought into contact with the other side of the sealing block 25 under the guide of the guide block 21; the flanges 11 on both sides are locked by the fasteners 3, and the sealing ring isolates the inside of the joint from the external environment. And pumping air in the joint in a vacuumizing mode, replacing the air with helium, and after the operation is carried out for a plurality of times, introducing liquid hydrogen to start conveying, wherein the oxygen content reaches the standard.

The above only be the preferred embodiment of the utility model discloses a not consequently restriction the utility model discloses a patent range, all are in the utility model discloses a conceive, utilize the equivalent structure transform of what the content was done in the description and the attached drawing, or direct/indirect application all is included in other relevant technical field the utility model discloses a patent protection within range.

Claims

1. A cryogenic joint, comprising a thermal insulation pipe, a core and a fastener, wherein the thermal insulation pipe comprises a first component and a second component, the first component comprises a first inner pipe and a first outer pipe which are coaxially arranged, and a flange arranged at one end of the first component, the flange extends outwards from the first inner pipe and protrudes out of the first outer pipe, the structure of the second component is the same as that of the first component, the core comprises two guide blocks, a sealing block and a second inner pipe and a second outer pipe which are coaxially arranged, the two guide blocks are correspondingly arranged at the two ends of the second outer pipe one by one, the sealing block is annularly arranged at the periphery of the second outer pipe, a second vacuum cavity is formed between the second inner pipe and the second outer pipe, the two ends of the second inner pipe are respectively provided with a core sealing head extending from the second inner pipe to the guide blocks, the core head is used for sealing a second vacuum cavity, the core body is assembled in the heat insulation pipe, the flange of the first component and the flange of the second component are clamped on two sides of the sealing block, the first component and the second component are connected through the fastener, and the sealing block is respectively connected with the flange of the first component and the flange of the second component in a sealing mode.

2. The cryogenic joint of claim 1, wherein the sealing block and the flange of the first component and the sealing block and the flange of the second component are sealed by an inner sealing ring and an outer sealing ring, two sealing grooves are formed in the side face of the sealing block, which is in contact with the flange, the inner sealing ring is mounted on one of the sealing rings, and the outer sealing ring is mounted on the other sealing ring.

3. The cryogenic coupling of claim 1, wherein a first vacuum chamber is formed between the first inner tube and the first outer tube.

4. The cryogenic joint of claim 1, wherein a sidewall of the first inner pipe opposite the first outer pipe is wrapped with an insulating wrap.

5. The cryogenic joint of claim 1, wherein the flanges are welded integrally to the first inner pipe and the first outer pipe, respectively.

6. The cryogenic joint of claim 1, wherein the seal block, the second inner tube, the second outer tube, and the core head are welded together.

7. The cryogenic connector of claim 1, wherein the ends of the second outer pipe are provided with steps, and two of the guide blocks are mounted on the steps in a one-to-one correspondence.

8. The cryogenic connector of claim 1, wherein the guide block is an annular body made of polytetrafluoroethylene.

9. The cryogenic joint of claim 1, wherein the side wall of the second inner pipe opposite the second outer pipe is wrapped with an insulating wrap.

10. The cryogenic joint of claim 1, wherein the second vacuum chamber is filled with a porous material.