阅读说明：本技术 一种低温液体传输管线装置 (Low-temperature liquid transmission pipeline device ) 是由 郝镇齐 张磊 于 2021-08-17 设计创作，主要内容包括：本发明公开了一种低温液体传输管线装置,用于向低温设备输送低温液体,包括传输管主体以及设置在传输管主体中的低温液体传输管路,所述低温液体传输管路包括：主管路,设置在传输管主体中心,用于向低温设备输送低温液体；支路,与所述主管路连通,且在主管路长度的至少一部分上围绕主管路布置,用于吸收从外界进入传输管主体的热量,以将主管路内的低温液体保持在基本恒定的低温状态。本发明能够减少低温液体的传输损耗,节约资源,使得输送至低温设备目标区域的低温液体为纯液态,不含气泡。此外,利用散热支路形成多级预冷触点,能够简化低温设备的冷却结构。(The invention discloses a cryogenic liquid transmission pipeline device, which is used for transmitting cryogenic liquid to cryogenic equipment, and comprises a transmission pipeline main body and a cryogenic liquid transmission pipeline arranged in the transmission pipeline main body, wherein the cryogenic liquid transmission pipeline comprises: the main pipeline is arranged in the center of the transmission pipe main body and used for transmitting low-temperature liquid to low-temperature equipment; a branch communicating with and arranged around the main conduit for at least a portion of its length for absorbing heat from the outside into the transfer conduit body to maintain cryogenic liquid within the main conduit at a substantially constant cryogenic state. The invention can reduce the transmission loss of the low-temperature liquid, saves resources, and ensures that the low-temperature liquid delivered to the target area of the low-temperature equipment is in a pure liquid state and does not contain bubbles. In addition, a multi-stage precooling contact is formed by utilizing the radiating branch, so that the cooling structure of the low-temperature equipment can be simplified.)

1. A cryogenic liquid transfer line assembly for transferring cryogenic liquid to cryogenic equipment, comprising a transfer line body and a cryogenic liquid transfer line disposed in the transfer line body, wherein the cryogenic liquid transfer line comprises: the main pipeline is arranged in the center of the transmission pipe main body and used for transmitting low-temperature liquid to low-temperature equipment; a branch communicating with and arranged around the main conduit for at least a portion of its length for absorbing heat from the outside into the transfer conduit body to maintain cryogenic liquid within the main conduit at a substantially constant cryogenic state.

2. The cryogenic liquid transfer pipeline assembly of claim 1 further comprising a distributor disposed within the transfer pipeline body, the distributor including an input port connected to the main pipeline for receiving the input cryogenic liquid, a first output port connected to the main pipeline for transferring a portion of the input cryogenic liquid to cryogenic equipment, and at least one second output port connected to one end of the branch pipeline for transferring another portion of the input cryogenic liquid to the branch pipeline.

3. The cryogenic liquid transfer pipeline apparatus of claim 2 wherein the transfer pipeline body is provided with a recovery port connected to the other end of the branch for delivering vaporized cryogenic liquid to a recovery unit.

4. The cryogenic liquid transfer pipeline apparatus of claim 1, wherein the legs are folded back a plurality of times along the length of the main pipeline over the at least a portion of the length of the main pipeline to form a plurality of successive folded back leg sections, the main pipeline being spaced apart from radially adjacent folded back leg sections and the radially adjacent folded back leg sections by an insulating material.

5. The cryogenic liquid transmission pipeline device according to claim 4, wherein the transmission pipeline main body comprises a central pipe and a plurality of outer pipes concentrically arranged outside the central pipe, the pipe walls of the central pipe and each outer pipe comprise a radiation shielding layer arranged at an inner layer and a heat insulating material layer superposed outside the radiation shielding layer, the main pipeline is arranged in the central pipe, and the turn-back branch sections are correspondingly arranged in annular cavities between the central pipe and the innermost outer pipe and between adjacent outer pipes.

6. The cryogenic liquid transfer line assembly of claim 5, wherein the reentrant legs are arranged in a spiral loop along the length of the pipe in the corresponding annular cavity.

7. The cryogenic liquid transfer line assembly of claim 6, wherein the helical turns of radially adjacent reentrant legs are in opposite directions.

8. The cryogenic liquid transfer line assembly of claim 1, wherein the transfer line body comprises an input port for connection to a cryogenic liquid supply and an output port for connection to cryogenic equipment, the output port comprising a pre-cool contact, the branch being connected to the pre-cool contact by a thermal connection.

9. The cryogenic liquid transfer line assembly of claim 8, wherein the pre-cooling contacts comprise a first pre-cooling contact and a second pre-cooling contact, the first pre-cooling contact is connected to a first portion of the branch via a first thermal connection, the second pre-cooling contact is connected to a second portion of the branch via a second thermal connection, and the first portion and the second portion of the branch are at different temperatures.

10. The cryogenic liquid transfer pipeline apparatus of any one of claims 1 to 9 wherein the branches comprise a first branch and a second branch connected in series to the main pipeline.

Technical Field

The invention relates to the technical field of low-temperature fluid medium transmission, in particular to a low-temperature liquid transmission pipeline device for transmitting low-temperature liquid for refrigeration to low-temperature equipment.

Background

Cryogenic equipment (generally referred to as a cryogenic device having a temperature below 100K) is generally not isolated from the use of cryogenic liquids, typically liquid nitrogen (atmospheric boiling point 77K) and liquid helium (atmospheric boiling point 4.2K). It is most common to provide cryogenic refrigeration by maintaining a cryogenic liquid at a boiling temperature in a vessel so that a stable cryogenic environment is achieved. Since the cryogenic liquid always receives heat from the outside and is finally volatilized and consumed, it is necessary to frequently replenish the cryogenic liquid in the vessel, for example, via a cryogenic liquid transfer line, during the operation of the cryogenic device.

Cryogenic liquid transfer lines are essentially pipes with good thermal insulation capabilities that allow cryogenic liquid to flow through the pipe and maintain the liquid at a relatively low temperature without absorbing too much heat and vaporizing it by providing a layer of thermal insulation (e.g., a vacuum layer) between the outer wall of the pipe and the inner wall of the pipe through which the liquid flows. A cryogenic liquid transfer line as shown in figure 1 comprises hard pipe sections at both ends and a hose section in the middle. The hard pipe part is used for being matched with different cryogenic equipment interfaces, the hose part is used for providing adjustable room in the pipe inserting process, and the length of the hose part is usually 1-5 meters.

However, the above-described transfer lines do not meet the use requirements for small flow, long cryogenic liquid transfers. For example, in the case of a cryogenic device for Continuous flow (Continuous flow) refrigeration, the source of cryogenic liquid is constantly flowing from the transfer line to the target refrigeration area, but the flow rate required is so small that a significant proportion of the cryogenic liquid has vaporized before it reaches the target area, making refrigeration inefficient. Meanwhile, the low-temperature liquid is gasified to generate bubbles, which affects the stable operation of the low-temperature equipment. Also, the longer the transfer line, the more pronounced the above-mentioned problems appear.

Disclosure of Invention

The invention provides a low-temperature liquid transmission pipeline device, which aims to solve the problem that low-temperature liquid absorbs heat from the outside and is gasified under the condition of small flow and reduce the loss of the low-temperature liquid in the transmission process.

According to an aspect of an embodiment of the present invention, there is provided a cryogenic liquid transfer pipeline apparatus for transferring cryogenic liquid to cryogenic equipment, including a transfer pipeline main body and a cryogenic liquid transfer pipeline disposed in the transfer pipeline main body, the cryogenic liquid transfer pipeline including: the main pipeline is arranged in the center of the transmission pipe main body and used for transmitting low-temperature liquid to low-temperature equipment; a branch communicating with and arranged around the main conduit for at least a portion of its length for absorbing heat from the outside into the transfer conduit body to maintain cryogenic liquid within the main conduit at a substantially constant cryogenic state.

In some other examples of the present invention, the transfer pipe further comprises a distributor disposed in the transfer pipe main body, the distributor including an input port connected to the main pipe for receiving the input cryogenic liquid, a first output port connected to the main pipe for transferring a portion of the input cryogenic liquid to the cryogenic equipment, and at least one second output port connected to one end of the branch for transferring another portion of the input cryogenic liquid to the branch.

In some other examples of the present invention, the main transfer pipe body is provided with a recycling port connected to the other end of the branch for transferring the gasified cryogenic liquid to a recycling device.

In some other examples of the invention, the legs are folded a plurality of times along the length of the main pipeline over the at least a portion of the length of the main pipeline to form a plurality of successive folded leg sections, the main pipeline being spaced apart from radially adjacent folded leg sections and the radially adjacent folded leg sections by a thermally insulating material.

In some other examples of the present invention, the main pipe body includes a central pipe and a plurality of outer pipes concentrically disposed outside the central pipe, the walls of the central pipe and each outer pipe include a radiation shielding layer disposed on an inner layer and a thermal insulation material layer stacked outside the radiation shielding layer, the main pipeline is disposed inside the central pipe, and the turn-back branch sections are correspondingly disposed in annular cavities between the central pipe and the innermost outer pipe and between adjacent outer pipes.

In other examples of the invention, the reentrant legs are arranged in a spiral loop along the length of the pipe in the corresponding annular cavity. In particular, the spiral winding directions of radially adjacent return branches are opposite.

In some other examples of the invention, the transfer tube body includes an input port for connection to a cryogenic liquid supply and an output port for connection to cryogenic equipment, the output port including a pre-cooling contact, the branch being connected to the pre-cooling contact by a thermal connection.

Furthermore, the pre-cooling contact comprises a first pre-cooling contact and a second pre-cooling contact, the first pre-cooling contact is connected with the first part of the branch circuit through a first thermal connection, the second pre-cooling contact is connected with the second part of the branch circuit through a second thermal connection, and the temperature of the first part of the branch circuit is different from that of the second part of the branch circuit.

In some other examples of the invention, the branch comprises a first branch and a second branch connected in series to the main conduit.

According to the invention, the heat dissipation branch communicated with the main cryogenic liquid transmission pipeline is arranged, so that the transmission loss of cryogenic liquid can be reduced, and the cryogenic liquid transmitted to the target area of the cryogenic equipment is in a pure liquid state and does not contain bubbles.

In addition, the invention utilizes the heat dissipation branch to form a multi-stage precooling contact, thereby simplifying the cooling structure of the low-temperature equipment.

In addition, the recovery interface is arranged at the outlet of the heat dissipation branch, so that the volatile part of the low-temperature liquid can be completely recovered, the totally-enclosed circulation is supported, and the resources are saved.

Drawings

FIG. 1 is a schematic view of an external structure of a conventional cryogenic liquid transfer line;

FIG. 2 is a schematic view of a cryogenic liquid transfer line assembly according to embodiment 1 of the present invention;

FIG. 3 is a schematic view of a cryogenic liquid transfer line assembly according to embodiment 2 of the present invention;

FIG. 4 is a schematic structural view of a cryogenic liquid transfer line assembly according to embodiment 3 of the present invention;

FIG. 5 is a schematic view of a cryogenic liquid transfer line assembly according to embodiment 4 of the present invention;

fig. 6 is a schematic cross-sectional view of a cryogenic liquid transfer line according to an embodiment of the invention.

Detailed Description

Hereinafter, a cryogenic liquid transfer line assembly according to the present disclosure will be described in detail with reference to the accompanying drawings and examples, but the present disclosure is not limited to these examples.

Further, it should be noted that in the description using the following drawings, the drawings are schematic, ratios of respective dimensions and the like are different from actual ones, and illustration other than components necessary in the description will be appropriately omitted for easy understanding.

Normal operation of cryogenic equipment typically relies on periodic or continuous supply of cryogenic cooling medium, such as the cooling system of a Magnetoencephalography (MEG) system, which requires periodic replenishment of liquid helium to the dewar. The invention provides a transfer pipeline device for transferring cryogenic liquid to such cryogenic equipment.

Fig. 2 is a schematic structural diagram of a cryogenic liquid transfer pipeline apparatus 100 according to embodiment 1 of the present invention, where the cryogenic liquid transfer pipeline apparatus 100 is used for transferring cryogenic liquid, such as liquid nitrogen, liquid helium, etc., to cryogenic equipment (not shown). As shown in fig. 2, the cryogenic liquid transfer line assembly 100 includes a transfer line body 11 and a cryogenic liquid transfer line disposed in the transfer line body 11. Illustratively, In fig. 2, the left end is an input port In of the cryogenic liquid transfer line device, the input port In is used for connecting with a cryogenic liquid supply source, and the right end is an output port Out of the cryogenic liquid transfer line device, the output port is used for connecting with a cryogenic device, so that the cryogenic liquid entering from the input port In is conveyed to the cryogenic device through the cryogenic liquid transfer line device.

In the embodiment shown in fig. 2, the cryogenic liquid transfer line assembly 100 is a linear structure, i.e., the input port and the output port extend along substantially the same line or two parallel lines. It will be appreciated that in other usage scenarios, the cryogenic liquid transfer line assembly may be configured in other shapes, such as an L-shape or a semi-frame shape as shown in fig. 1.

As shown in fig. 2, the cryogenic liquid transfer line includes: a main pipeline 12 arranged at the center of the transmission pipe main body 11 and used for transmitting cryogenic liquid to cryogenic equipment; a branch 14, communicating with said main conduit 12 and arranged around the main conduit 12 for at least a portion of the length of the main conduit 12, is intended to absorb heat entering the transfer conduit body 11 from the outside, so as to maintain the cryogenic liquid inside the main conduit 12 in a substantially constant cryogenic state.

In an embodiment of the present invention, the main pipeline 12 is a single pipeline. However, it will be understood by those skilled in the art that the main pipeline 12 may be provided in multiple ways to provide multiple ways of the same or different cryogenic liquids to one or more cryogenic devices, depending on the application.

In the present invention, the communication between the main conduit 12 and the branch conduit 14 is achieved by a distributor 13, which may be, for example, a tee joint, a multi-way joint, or the like. In another embodiment, the distributor may also be a control valve, and the control valve is in signal connection with the control unit through a wired or wireless mode, and the on-off control and/or the flow rate regulation of the flow path are performed according to the control signal.

As shown in fig. 2, the distributor 13 is arranged in the transfer tube body and comprises an input port, a first output port and at least one second output port. The distributor 13 is connected in series to a main pipeline 13, and the input port is connected to one end of the main pipeline 12 and is configured to receive an input cryogenic liquid. The first output port is connected to the other end of the main pipeline 12, and is used for transmitting a part of the input cryogenic liquid to cryogenic equipment. The second outlet is connected to one end (inlet end) of the branch 14 for delivering another portion of the input cryogenic liquid to the branch.

In this embodiment of the present invention, the distributor 13 is disposed near the output port Out of the cryogenic liquid transmission pipeline device, that is, after the cryogenic liquid enters the main pipeline 12 through the input port In, the cryogenic liquid first passes through the main pipeline 12 of substantially the entire length, and then enters the distributor 13, the distributor 13 divides the cryogenic liquid, and a part (for example, 70% to 85% of the cryogenic liquid) enters the downstream main pipeline 12 through the first output port, and is continuously transmitted to the cryogenic equipment through the output port Out 1; another portion (for example, 15% to 30% of the cryogenic liquid) enters the inlet end of the branch 14 through the second outlet of the distributor 13.

With continued reference to FIG. 2, the legs 14 are folded a plurality of times along the length of the main conduit 12 over the at least a portion of the entire length of the main conduit 12 to form a plurality of successive folded leg segments 14-1, 14-2, 14-3, 14-4. In the illustrated embodiment, each of the reentry legs has a length that is close to or substantially the same as the overall length of the main conduit 12, i.e., the legs 14 are reentrant a plurality of times along the length of the main conduit 12 over the entire length of the main conduit 12. In another embodiment, the branch passage 14 may be formed with the folded branch passage only in a part of the entire length of the main pipe 12, for example, 1/2 to 4/5 of the entire length of the main pipe 12.

In the present invention, the term "continuous branch sections of the folded branches" refers to the sections of the same branch which are folded along the length direction of the main pipeline for a plurality of times, and the sections of the branches are connected integrally. Here, "integrally connected" also includes a case where the branch links are integrally connected by joints.

In the embodiment shown in FIG. 2, leg 14 extends from divider 13 along main conduit 12 and makes up 4 leg segments 14-1, 14-2, 14-3, 14-4 through 3 turns, i.e., including a first leg segment 14-1 before no turn, a second leg segment 14-2 made up of a 1 st turn, a third leg segment 14-3 made up of a 2 nd turn, and a fourth leg segment 14-4 made up of a 3 rd turn. Each leg segment has a different radial distance relative to the main leg 12 and the main leg 12 is spaced from a radially adjacent turnaround leg 14-1 and radially adjacent turnaround legs 14-1, 14-2, 14-3, 14-4 by an insulating material.

In the embodiment of the invention, a thin pipe branch is led out from a low-temperature liquid transmission pipe (main pipeline) to form a cooling branch, the cooling branch shuttles back and forth in a heat insulation material layer between the inner wall and the outer wall of the transmission pipeline, the inner layer of the transmission pipeline gradually flows to the outer layer, and the liquid/gas temperature in the branch is gradually raised by absorbing heat from the outside in the flowing process, so that a heat insulation material layer of the transmission pipeline keeps a stable temperature gradient from inside to outside, the maximum heat which can be absorbed in the process of gasifying and heating the low-temperature liquid is fully utilized, the influence of the outside temperature on the low-temperature liquid in the main pipeline is furthest reduced, the low-temperature liquid in the main pipeline is kept in a basically constant low-temperature state, and the phenomenon that bubbles generated by gasifying the low-temperature liquid influence the stable work of low-temperature equipment is avoided.

Although the embodiment shows that the branch 14 passes 3 times of switchback from the distributor 13 along the main pipeline to form 4 branch sections, those skilled in the art will understand that the number of switchback can be increased or decreased according to actual conditions. Meanwhile, the cooling branches led out from the distributor 13 can also be multi-path.

Fig. 6 shows the sectional structure of the cryogenic liquid transfer line in this embodiment, which is used to represent the structure of the transfer line body 11, and the arrangement of the branch sections of the main line 12 and the branch line 14 in the transfer line body 11.

As shown in fig. 6, the transfer tube body 11 includes a central tube and a plurality of outer tubes (4 outer tubes are shown) concentrically disposed outside the central tube. The pipe wall of the central pipe and the pipe wall of each outer layer pipe respectively comprise a radiation shielding layer 111 arranged at the inner layer and a heat insulating material layer 112 superposed outside the radiation shielding layer, the main pipeline 12 is arranged in the central pipe, and the turn-back branch road sections 14-1, 14-2, 14-3 and 14-4 are correspondingly arranged in annular cavities between the central pipe and the innermost layer outer layer pipe and between adjacent outer layer pipes.

In the present invention, the radiation shielding layer 111 in the thermal insulation material layer may be an aluminum film, and the thermal insulation film 112 may be a high-density foam or a plastic mesh. The outermost layer of the conveying pipe body 11 is a corrugated pipe outer wall 113.

As can be seen in FIG. 6, each of the leg segments 14-1, 14-2, 14-3, 14-4 has a different radial distance from the main pipeline 12, and the main pipeline 12 is spaced from the radially adjacent return leg segments 14-1 and from the radially adjacent return leg segments 14-1, 14-2, 14-3, 14-4 by a radiation shield layer 111 and a layer of thermal insulation material 112 overlying the radiation shield layer. Furthermore, the first branch portion 14-1 connected to the distributor (i.e. not turned back) is located at the radially innermost layer, i.e. at the smallest radial distance from the main line, and then the branch portions 14-2, 14-3, 14-4 formed by the turn back are located at increasing radial layers as the number of turns increases. Therefore, the temperature-reducing branch flows from the inner layer of the transmission pipeline to the outer layer gradually, and absorbs heat from the outside in the flowing process, so that the temperature of liquid/gas in the branch is gradually increased, and the heat insulation material layer of the transmission pipeline keeps a stable temperature gradient from inside to outside.

In the embodiment of the invention, each turn-back branch section is arranged in a spiral surrounding manner in the corresponding annular cavity along the length direction of the pipe, so that heat from all directions of the pipeline can be absorbed, and the temperature of the fluid in the branch section is uniformly increased.

More preferably, the spiral winding directions of radially adjacent reentrant branches are opposite. For example, the branch portion 14-2 located in the 2 nd annular cavity is spirally wound in the left-hand direction, and the branch portion 14-1 located in the 1 st annular cavity and the branch portion 14-3 located in the 3 rd annular cavity are spirally wound in the right-hand direction. By arranging the branch road sections in the mode, the influence of temperature rise between the adjacent branch road sections is avoided to the maximum extent, and the uniform absorption of heat entering the pipeline from the outside is further improved.

With reference to fig. 2, the transfer pipe main body 11 is provided with a recovery interface Out2 connected to the other end (tail end) of the branch for transferring the gasified medium of the cryogenic liquid to a recovery device, and the gasified medium is liquefied again by the recovery device and then supplied to the cryogenic liquid supply source. The recovery interface Out2 may be located at the end of the output port of the pipeline apparatus, or may be located on the side wall of the pipeline apparatus adjacent to the output port or elsewhere.

In the present invention, the output port of the transmission tube main body 11 is further provided with at least one pre-cooling contact, and the branch 14 is connected with the pre-cooling contact through a thermal connection.

Since general cryogenic equipment has different temperature regions, such as several heat shields from the outer shell to the coldest region, and the temperature gradually decreases from outside to inside, good heat insulation effect can be achieved. Wherein thermal shields in different locations need to be connected to pre-cooled contacts of different temperatures in order to have their temperature "anchored" at a particular temperature. The transmission pipeline is provided with the multistage precooling contacts at the tail end, and the transmission pipeline is in good thermal connection with the precooling contacts at the tail end by utilizing the characteristic that the temperature of different positions of the cooling branch is different, so that the transmission pipeline can not only transmit low-temperature liquid, but also provide one or more precooling contacts at one temperature.

As shown in fig. 2, in this embodiment of the invention, the pre-cooling contacts comprise a first pre-cooling contact 151 and a second pre-cooling contact 152, which are axially spaced along the pipeline. The first pre-cooling contact 151 is connected to a first portion of the branch 14 (a branch turning point adjacent to the pre-cooling contact 151) by a first thermal connection 161, and the second pre-cooling contact 152 is connected to a second portion of the branch 14 (an end of a fourth branch segment 14-4) by a second thermal connection 162. The first part and the second part of the branch circuit are in different positions or belong to different branch circuit sections, so that the temperatures are different, and the two precooling contacts have different temperatures through thermal connection, namely, the two precooling contacts with different temperatures are provided through the structure.

In the present invention, the pre-cooling contact may be formed of, for example, an oxygen-free copper ring. The thermal connection can be made of, for example, a copper braid which is flexible and has high heat conduction efficiency, or other heat conduction materials.

Although the embodiments of the present invention are described in detail with reference to the drawings, although the above description uses "main pipeline" and "branch pipeline", those skilled in the art will understand that "main pipeline" and "branch pipeline" may be formed by independent solid pipes, or may be formed by forming a continuous cavity in the transfer pipe main body 11.

Furthermore, although not specifically illustrated, it will be understood by those skilled in the art that when the "main pipeline" and "branch" are formed of solid pipes, it may be necessary to provide the necessary support structures in the main transport pipe body 11 to support the pipes, such as support frames or baffles in the respective annular cavities. At the same time, relative movement between the pipe and the support structure should be possible, considering that the pipeline apparatus is often bent when in use.

In addition, when cryogenic liquids got into the pipeline, because expend with heat and contract with cold reason can lead to the pipeline to warp, for this reason the at least part position of main line and branch road sets up the flexion of reserving, for the pipeline shrinkage deformation provides the surplus, avoids the pipeline to receive low temperature to influence the damage.

Fig. 3 is a schematic structural diagram of a cryogenic liquid transfer pipeline apparatus 200 according to embodiment 2 of the present invention. The difference from embodiment 1 is that the distributor 13 is disposed near the input port In of the cryogenic liquid transfer pipeline assembly 200, and at this time, since the heat dissipation branch section adjacent to the main pipeline 12 is closer to the cryogenic liquid supply source and "synchronized" with the main pipeline, the influence on the temperature of the cryogenic liquid In the main pipeline is less.

In addition, in this embodiment, a pre-cool contact 251 is provided at the output port of cryogenic liquid transfer line assembly 200, which is connected to the adjacent turnaround point of branch 14 by a thermal connection 261.

Fig. 4 is a schematic structural diagram of a cryogenic liquid transfer pipeline apparatus 300 according to embodiment 3 of the present invention. The difference from embodiment 2 is that the branch 14 includes a first branch 141 and a second branch 142 connected in series to the main line 11. The first branch 141 is communicated with the main pipeline 12 through the first distributor 131, and the second branch 142 is communicated with the main pipeline 12 through the second distributor 132. The first distributor 131 and the second distributor 132 are connected in series to the main pipeline 12 in sequence.

Furthermore, a first pre-cooling contact 351 is provided on the outer wall of the transfer tube body 11 between the first branch 141 and the second branch 142, and is connected to the turning point of the adjacent branch 141 by a first thermal connection 361. At the output port of cryogenic liquid transfer line assembly 300 is provided a second pre-cooling contact 352 which is connected to the return point of adjacent branch 142 by a thermal connection 362.

Fig. 5 is a schematic structural diagram of a cryogenic liquid transfer pipeline apparatus 400 according to embodiment 4 of the present invention. The difference from embodiment 3 is that a pre-cooling contact 451 is provided on the outer wall of the transfer tube main body 11 near the input port In of the cryogenic liquid transfer tube line device 400, and is connected to the turn-back point of the adjacent branch 141 through a thermal connection 461.

Similarly, although the input port In of the cryogenic liquid transfer line assembly 400 is configured In a straight line In the embodiment shown In fig. 5, the design is not limited thereto, and the L-shaped configuration shown In fig. 3 and 4 is also applicable.

Although the present invention is described in the above 4 embodiments, it is understood by those skilled in the art that the technical means adopted by the above embodiments can be combined or replaced between different embodiments.

The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same. Although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.