CN218625899U

CN218625899U - Rotary joint device for ultralow-temperature medium conveying

Info

Publication number: CN218625899U
Application number: CN202223203659.6U
Authority: CN
Inventors: 杨亮; 宋坤; 许佳伟; 肖立; 盖小刚; 范嘉堃; 邱灶杨; 郝思佳; 张彧; 李鑫
Original assignee: CNOOC Gas and Power Group Co Ltd
Current assignee: CNOOC Gas and Power Group Co Ltd
Priority date: 2022-12-01
Filing date: 2022-12-01
Publication date: 2023-03-14
Anticipated expiration: 2032-12-01

Abstract

The utility model relates to a rotary joint device that ultra-low temperature medium was carried and was used, including upper portion rotary joint and lower part rotary joint, the upper portion rotary joint internal fixation has vertical first upper chamber wall, the lower part rotary joint internal fixation has vertical first lower chamber wall, upper portion rotary joint and lower part rotary joint rotate to be connected, first upper chamber wall and first lower chamber wall interconnection constitute first inner wall, constitute low temperature liquid phase fluid passageway in the first inner wall, and the outside of first inner wall forms low temperature gaseous phase fluid passageway, upper portion rotary joint's top is formed with liquid phase fluid import, lower part rotary joint's bottom is formed with liquid phase fluid export, be equipped with gaseous phase fluid import on lower part rotary joint, and be equipped with gaseous phase fluid export on upper portion rotary joint. The utility model discloses a rotary joint device just can accomplish low temperature liquid phase fluid and gaseous phase fluid and carry simultaneously to can realize the nimble adjustment of the direction of admitting air and the direction of giving vent to anger place pipeline direction.

Description

Rotary joint device for ultralow-temperature medium conveying

Technical Field

The utility model relates to a low temperature medium carries technical field, concretely relates to ultra-low temperature medium is carried and is used rotary joint device.

Background

A Floating Production Storage and offloading Unit (FLNG) is a Floating Production device for offshore Natural Gas field development, which is positioned at sea by a mooring system, has functions of exploiting, processing, liquefying, storing, and offloading Natural Gas, and realizes the exploitation and Natural Gas transportation of an offshore Natural Gas field by being used in combination with a Liquefied Natural Gas (LNG) ship. The development of the offshore gas field by using the FLNG ends the single mode that the offshore gas field can only be transported to the shore by adopting a pipeline, saves the transportation cost and does not occupy land space.

The LNG unloading arm is a rigid hinged pipeline system which is arranged on a wharf or FLNG and used for LNG unloading, and the main structure of the LNG unloading arm comprises a rotary joint, an outer arm, an inner arm, a base vertical pipe, a rotary joint connecting the inner arm and the base vertical pipe, and other process pipelines, supporting structures and accessories thereof. Large-scale LNG unloading arm stands at LNG receiving station wharf area foremost, connects LNG boats and ships and land pipeline and storage facility's key core equipment as the receiving station, "throat" of whole receiving station. When the LNG carrier arrives at a special wharf of a receiving station, LNG is sent into a storage tank of the receiving station by using a cryogenic pump on the LNG carrier through a liquid-phase discharge arm and a discharge pipeline, and meanwhile Boil-off gas (BOG) gas in the storage tank returns to the LNG carrier through a gas return pipeline and a gas-phase gas return arm. In the LNG unloading arm operation process, the end part of the unloading arm is guided to be interconnected with the LNG ship receiving end through the traction line, so that accurate butt joint can be realized under the condition of relative motion, a hydraulic system of the unloading arm is controlled, and the unloading arm can bear the influence of speed and acceleration caused by ship motion.

Aiming at the severe sea condition conditions of south China sea, if the problem of differential motion between an FLNG floating platform and a carrier of a transport ship is difficult to effectively solve by the existing mooring technology and the traditional rigid discharge arm, a specially designed low-temperature outward-conveying discharge system needs to be adopted to meet the severe requirements of low temperature and shaking working conditions. The advantages of low temperature hose conveying system in aspects such as weight, pliability, corrosion resistance, heat-proof quality are obvious, and during FLNG exports the operation, the effective mode of going is to adopt the cluster to lean on the mooring, is connected with the LNG transport ship through mooring cable promptly to use the low temperature hose to realize LNG and unload, when requiring the low temperature hose to bear the ultra-low temperature, still need overcome the influence of relative motion between FLNG and the LNG transport ship.

In addition, the liquid hydrogen shipping test is successfully implemented, a more economic and safe mode is provided for the liquid hydrogen industrial chain, and the method has positive significance for the popularization and the use of hydrogen energy in the global range and has stronger development potential in the future. The liquid hydrogen has the characteristics of ultralow temperature, easy volatilization, flammability and explosiveness, and the liquid hydrogen ship has large loading, unloading and conveying difficulty, high safety requirement and many technical barriers. The liquid hydrogen ship shore loading and unloading system has the advantages of severe operation condition, strict requirement on action precision and complex coordination of electromechanical systems, not only has the functions of quick butt joint, emergency separation, automatic closing and the like, but also can bear the long-time-253 ℃ ultralow temperature test and automatically adapt to the influence of tide fall.

In conclusion, key technologies of ultra-low temperature fluid conveying systems such as an LNG rigid unloading arm, an LNG low-temperature hose conveying system, a liquid hydrogen ship shore loading and unloading system and the like all relate to various links such as low-temperature material selection, molding manufacturing, sealing, test verification and the like. The material selection and structural design difficulty is large, the processing and manufacturing and performance testing work are difficult, the ultra-low temperature sealing, connecting and leakage monitoring difficulty is high, the whole set of low temperature conveying system has a complex structure, and the safety requirement is high. The rotary joint is used as a key component, and the performance of the rotary joint directly influences the safe and stable operation of the ultralow-temperature fluid conveying system. The rotary joint is used as a key structural component for low-temperature medium overflowing and steering, and is required to be capable of preventing low-temperature medium leakage, bearing high-strength load and pressure and having low friction loss during rotation under the ultralow-temperature dynamic working condition.

At present, when the rotary joint device adopted in the prior art conveys ultralow temperature media, liquid phase and gas phase are respectively carried out, namely, the liquid phase pipeline is provided with a corresponding rotary joint, and the same is true for the gas phase pipeline, so that the ultralow temperature conveying system is more complex. Taking the above LNG rigid unloading arm as an example, in the process of loading and unloading the LNG ship shore, LNG is transported from the carrier to the LNG storage facility on the shore through the liquid phase pipeline where the rotary joint is located, and in this process, BOG boil-off gas generated by LNG vaporization is also transported into the carrier along the pipeline in the opposite direction to balance the operating pressure between the ship shore. Therefore, a plurality of liquid phase pipeline rotary joints and gas phase pipeline rotary joints are arranged on corresponding low-temperature conveying pipelines respectively, so that the whole system is complex in structure, and system resources are not optimally configured.

Disclosure of Invention

The utility model aims at providing an ultra-low temperature medium is carried and is used rotary joint device to solve among the prior art because liquid phase attitude and gaseous phase are gone on respectively and lead to the problem that whole system architecture is complicated when adopting rotary joint device to carry ultra-low temperature medium.

In order to achieve the purpose, the utility model adopts the following technical proposal:

the utility model provides a rotary joint device for conveying ultralow temperature media, which comprises an upper rotary joint and a lower rotary joint, wherein a vertical first upper cavity wall is fixed in the upper rotary joint, and a vertical first lower cavity wall is fixed in the lower rotary joint;

the upper rotary joint is rotatably connected with the lower rotary joint, the first upper cavity wall and the first lower cavity wall are interconnected to form a first inner wall, a low-temperature liquid-phase fluid channel is formed in the first inner wall, an annular and closed low-temperature gas-phase fluid channel is formed outside the first inner wall, a liquid-phase fluid inlet is formed in the position, located at the top of the upper rotary joint, of the low-temperature liquid-phase fluid channel, a liquid-phase fluid outlet is formed in the position, located at the bottom of the lower rotary joint, of the low-temperature liquid-phase fluid channel, a gas-phase fluid inlet communicated with the interior of the low-temperature gas-phase fluid channel is formed in the outer wall of the lower rotary joint, and a gas-phase fluid outlet communicated with the interior of the low-temperature gas-phase fluid channel is formed in the outer wall of the upper rotary joint.

Furthermore, a rotating assembly is arranged between the upper rotating joint and the lower rotating joint and comprises a bearing, a first bearing jacket and a second bearing jacket, the first bearing jacket is annularly fixed at the bottom of the upper rotating joint, the second bearing jacket is annularly fixed at the top of the lower rotating joint, the first bearing jacket is arranged on the inner side of the second bearing jacket, and the bearing is arranged between the first bearing jacket and the second bearing jacket.

Furthermore, the outer edge of the bottom of the upper rotary joint extends outwards horizontally to form an upper connecting plate, the first bearing jacket is fixed on the upper connecting plate through a plurality of first pins, the outer edge of the top of the lower rotary joint extends outwards horizontally to form a lower connecting plate, the second bearing jacket is fixed on the lower connecting plate through a plurality of second pins, the outer ring wall of the first bearing jacket is arranged in a manner of clinging to the inner ring wall of the second bearing jacket, a first clamping groove is formed in the outer ring wall of the first bearing jacket, a second clamping groove corresponding to the first clamping groove is formed in the inner ring wall of the second bearing jacket, and the bearing is arranged in the first clamping groove and the second clamping groove.

Furthermore, a vertical second upper cavity wall is fixed in the upper rotary joint, the second upper cavity wall is sleeved outside the first upper cavity wall, a vertical second lower cavity wall is fixed in the lower rotary joint, the second lower cavity wall is sleeved outside the first lower cavity wall, the second upper cavity wall and the second lower cavity wall are interconnected to form a second inner wall, an annular and closed low-temperature gas-phase fluid channel is formed between the second inner wall and the outer wall of the rotary joint device, and a vacuum layer is formed between the second inner wall and the first inner wall.

Furthermore, first go up the chamber wall with between the first chamber wall down, the second go up the chamber wall with connect through seal assembly respectively between the chamber wall down, seal assembly includes sealing ring and pressure spring first go up the chamber wall with annular seal groove has been seted up on the bottom face on the chamber wall on the second respectively, the inslot bottom surface of seal groove has been seted up annular and has been accomodate the groove, the sealing ring cooperation assembly is in the seal groove, and it sets up a plurality of to accomodate the inslot along the circumferencial direction pressure spring.

Further, a plurality of sealing assemblies are arranged on the first inner wall and the second inner wall respectively along the horizontal direction.

The utility model discloses owing to take above technical scheme, it possesses following beneficial effect:

through carrying out the structural innovation design to traditional rotary joint, set up the rotary joint device that constitutes by upper portion rotary joint and lower part rotary joint combination, utilize and constitute low temperature liquid phase fluid passageway in the first inner wall, and constitute low temperature gaseous phase fluid passageway outside the first inner wall, thereby realize adopting a rotary joint device, just can accomplish low temperature liquid phase fluid and gaseous phase fluid and carry simultaneously, have characteristics such as integration and compact structure, simple to operate is nimble, and set up through the rotation of upper portion rotary joint and lower part rotary joint, realize that upper portion rotary joint and lower part rotary joint two parts can the rotation in a circumferential direction, can realize the nimble adjustment of the direction of the pipeline that admit air direction and give vent to anger the place of direction from this.

Drawings

Various additional advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Like parts are designated with like reference numerals throughout the drawings. In the drawings:

fig. 1 is a schematic view of an overall structure of a rotary joint device according to an embodiment of the present invention;

fig. 2 is an enlarged schematic view of the structure a in fig. 1.

The reference symbols in the drawings denote the following:

1. an upper swivel joint; 11. a first upper chamber wall; 12. a liquid phase fluid inlet; 13. a gas phase fluid outlet; 14. a first connecting flange; 15. a fourth connecting flange; 16. an upper connecting plate; 17. a first pin; 18. a second upper chamber wall; 2. a lower rotary joint; 21. a first lower chamber wall; 22. a liquid phase fluid outlet; 23. a gas phase fluid inlet; 24. a second connecting flange; 25. a third connecting flange; 26. a lower connecting plate; 27. a second pin; 28. a second lower chamber wall; 3. a low temperature liquid phase fluid channel; 4. a low temperature gas phase fluid channel; 5. a rotating assembly; 51. a bearing; 52. a first bearing cartridge; 53. a second bearing cartridge; 6. a vacuum layer; 7. a seal assembly; 71. a seal ring; 72. a compression spring; 8. a sealing groove; 9. a receiving groove.

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The liquid phase and the gas phase are respectively carried out when the traditional rotary joint device is adopted to convey the ultralow temperature medium, so that the whole system is complex in structure. The utility model provides a rotary joint device that ultra-low temperature medium carried usefulness, rotary joint device that ultra-low temperature medium carried usefulness include upper portion rotary joint and lower part rotary joint, and upper portion rotary joint and lower part rotary joint rotate to be connected, are equipped with first inner wall in the rotary joint device, constitute low temperature liquid phase fluid passageway in the first inner wall, and constitute annular and confined low temperature gaseous phase fluid passageway outside the first inner wall. The upper rotary joint and the lower rotary joint can rotate circumferentially, so that the flexible adjustment of the pipeline direction of the air inlet direction and the air outlet direction can be realized, the simultaneous conveying of low-temperature liquid phase fluid and gas phase fluid can be completed by adopting one rotary joint device, and the device has the characteristics of integration, compact structure and the like.

The embodiment of the present invention will be described in detail by way of examples.

Examples

As shown in fig. 1, the present invention provides a rotary joint device for transporting an ultra-low temperature medium, comprising an upper rotary joint 1 and a lower rotary joint 2. A first vertical upper cavity wall 11 is fixed in the upper rotary joint 1, and a first vertical lower cavity wall 21 is fixed in the lower rotary joint 2. The upper rotary joint 1 and the lower rotary joint 2 are rotatably connected, and the first upper cavity wall 11 and the first lower cavity wall 21 are interconnected to form a first inner wall. The first inner wall forms a low-temperature liquid phase fluid channel 3, and the outer side of the first inner wall forms an annular and closed low-temperature gas phase fluid channel 4. A liquid phase fluid inlet 12 is formed in the lower rotary joint 1 at the top of the lower rotary joint 3, and a liquid phase fluid outlet 22 is formed in the lower rotary joint 2 at the bottom of the lower rotary joint 3. The outer wall of the lower rotary joint 2 is provided with a gas phase fluid inlet 23 communicated with the low-temperature gas phase fluid channel 4, and the outer wall of the upper rotary joint 1 is provided with a gas phase fluid outlet 13 communicated with the low-temperature gas phase fluid channel 4.

Wherein, a first connecting flange 14 fixed at the top of the upper rotary joint 1 is arranged at the liquid phase fluid inlet 12 and used for being interconnected with an upstream liquid phase fluid pipeline; the liquid phase fluid outlet 22 is provided with a second connecting flange 24 fixed at the bottom of the lower swivel joint 2 for interconnecting with a downstream liquid phase fluid pipe, so that the low temperature liquid phase medium such as LNG or liquid hydrogen from upstream enters the interior of the swivel joint device along the low temperature liquid phase fluid channel 3 and enters the downstream pipe. In addition, a third connecting flange 25 fixed on the outer wall of the lower rotary joint 2 is arranged at the gas-phase fluid inlet 23 and is used for being interconnected with a return pipeline of the gas-phase medium in the low-temperature conveying system; the gas phase fluid outlet 13 is provided with a fourth connecting flange 15 fixed on the top of the upper rotary joint 1 for interconnecting with a downstream pipeline, so that the gas phase medium needing to be returned in the cryogenic conveying system enters the cryogenic gas phase fluid channel 4 inside the rotary joint device through the gas phase fluid inlet 23 and is discharged into a downstream pipeline connected with the cryogenic gas phase fluid channel through the gas phase fluid outlet 13. Therefore, the low-temperature liquid phase fluid and the gas phase fluid can be simultaneously conveyed by adopting one rotary joint device, and the device has the characteristics of integration, compact structure and the like.

Further, a rotating assembly 5 is arranged between the upper rotating joint 1 and the lower rotating joint 2, and the rotating assembly 5 comprises a bearing 51, a first bearing jacket 52 and a second bearing jacket 53. A first bearing collet 52 is fixed annularly at the bottom of the upper rotary joint 1 and a second bearing collet 53 is fixed annularly at the top of the lower rotary joint 2. The first bearing collet 52 is disposed inside the second bearing collet 53, and the bearing 51 is installed between the first bearing collet 52 and the second bearing collet 53. Specifically, an upper connection plate 16 is formed by horizontally extending an outer edge of a bottom portion of the upper rotary joint 1 outward, and the first bearing collet 52 is fixed to the upper connection plate 16 by a plurality of first pins 17. The outer edge of the top of the lower rotary joint 2 extends horizontally outward to form a lower connecting plate 26, and the second bearing collet 53 is fixed to the lower connecting plate 26 by a plurality of second pins 27. The outer ring wall of the first bearing jacket 52 is closely attached to the inner ring wall of the second bearing jacket 53, a first clamping groove is formed in the outer ring wall of the first bearing jacket 52, and a second clamping groove corresponding to the first clamping groove is formed in the inner ring wall of the second bearing jacket 53. The bearings 51 are preferably ball bearings and are disposed in the first and second clip grooves. Through the arrangement of the structure, the position of the bearing jacket is kept relatively stable through the pin, the upper rotary joint 1 and the lower rotary joint 2 can rotate in the circumferential direction through the bearing 51, and the gas-phase fluid inlet 23 and the gas-phase fluid outlet 13 are driven to rotate together in the rotating process, so that the flexible adjustment of the directions of pipelines in which the gas inlet direction and the gas outlet direction are located can be realized.

One preferred embodiment is: a vertical second upper cavity wall 18 is fixed in the upper rotary joint 1, and the second upper cavity wall 18 is sleeved outside the first upper cavity wall 11. A second vertical lower cavity wall 28 is fixed in the lower rotary joint 2, the second lower cavity wall 28 is sleeved outside the first lower cavity wall 21, and the second upper cavity wall 18 and the second lower cavity wall 28 are interconnected to form a second inner wall. An annular and closed low-temperature gas-phase fluid channel 4 is formed between the second inner wall and the outer wall of the rotary joint device, and a vacuum layer 6 is formed between the second inner wall and the first inner wall. Through the setting of this structure, make low temperature liquid phase fluid channel 3 and low temperature gaseous phase fluid channel 4 mutual independence to realize low temperature liquid phase fluid and gaseous phase fluid and carry simultaneously, and it is regional to utilize the annular region that forms between first inner wall and the second inner wall to be vacuum layer 6, realize through the adiabatic mode of vacuum heat preservation to the cold insulation of ultra-low temperature liquid phase medium, the vacuum is the most effective mode among the adiabatic mode of cold preservation, is particularly useful for the utility model relates to a technical operating mode, for example LNG temperature-163 ℃, liquid hydrogen temperature-253 ℃, can avoid the inside ultra-low temperature of rotary joint device to the outside conduction from this, reduce the gasification of low temperature liquid, effectively prevent the safety problem that inside superpressure leads to.

One preferred embodiment is: the first upper cavity wall 11 and the first lower cavity wall 21 are connected with each other, and the second upper cavity wall 18 and the second lower cavity wall 28 are connected with each other through the sealing assembly 7. The seal assembly 7 comprises a seal ring 71 and a compression spring 72. Seted up annular seal groove 8 on the bottom face of first upper chamber wall 11 and second upper chamber wall 18 respectively, seted up annular on the inslot bottom surface of seal groove 8 and accomodate groove 9, sealing ring 71 cooperation assembly is in seal groove 8 to set up a plurality of pressure spring 72 along the circumferencial direction in accomodating groove 9. By the arrangement of the structure, by using the sealing assembly 7 composed of the sealing ring 71 and the compression spring 72, after the upper rotary joint 1 and the lower rotary joint 2 are butted, the sealing ring 71 on the first upper cavity wall 11 is tightly abutted against the top end face of the first lower cavity wall 21 through the compression spring 72 at the top, and the sealing ring 71 on the second upper cavity wall 18 is tightly abutted against the top end face of the second lower cavity wall 28 through the compression spring 72 at the top, so that the fixation of the sealing assembly 7 and the sealing between the low-temperature liquid phase fluid channel 3 and the low-temperature gas phase fluid channel 4 are realized. Preferably, a plurality of seal assemblies 7 are respectively arranged on the first inner wall and the second inner wall along the horizontal direction, and two seal rings 71 are used for further improving the sealing performance. Wherein, the material of sealing ring 71 is preferably one of polytetrafluoroethylene, polyimide, the fluorinated ethylene propylene that gathers, can satisfy the sealed requirement of ultra-low temperature operating mode, and these sealing rings 71 constitute and to realize relative rotation and still guarantee sealed effect between upper chamber wall and the lower chamber wall.

The utility model discloses a rotary joint device for ultra-low temperature medium is carried through setting up the rotary joint device that comprises upper portion rotary joint 1 and 2 combinations of lower part rotary joint, utilize and constitute low temperature liquid phase fluid passage 3 in the first inner wall, and first inner wall constitutes low temperature gaseous phase fluid passage 4 outward, thereby realize adopting a rotary joint device, just can accomplish low temperature liquid phase fluid and gaseous phase fluid and carry simultaneously, have characteristics such as integrated integration and compact structure, it can vertically install, also can transverse arrangement, simple to operate is nimble, and can circumferential direction through upper portion rotary joint 1 and 2 two parts of lower part rotary joint, can realize the direction of admitting air and give vent to anger the nimble adjustment of direction place pipeline direction from this.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims

1. The utility model provides a rotary joint device that ultra-low temperature medium was carried and is used which characterized in that: the rotary joint device for conveying the ultralow-temperature medium comprises an upper rotary joint and a lower rotary joint, wherein a first vertical upper cavity wall is fixed in the upper rotary joint, and a first vertical lower cavity wall is fixed in the lower rotary joint;

the upper rotary joint is rotationally connected with the lower rotary joint, the first upper cavity wall and the first lower cavity wall are interconnected to form a first inner wall, a low-temperature liquid-phase fluid channel is formed in the first inner wall, an annular and closed low-temperature gas-phase fluid channel is formed on the outer side of the first inner wall, a liquid-phase fluid inlet is formed at the top of the upper rotary joint of the low-temperature liquid-phase fluid channel, the low-temperature liquid phase fluid channel is positioned at the bottom of the lower rotary joint to form a liquid phase fluid outlet, the outer wall of the lower rotary joint is provided with a gas phase fluid inlet communicated with the low-temperature gas phase fluid channel, and the outer wall of the upper rotary joint is provided with a gas phase fluid outlet communicated with the low-temperature gas phase fluid channel.

2. A rotary joint device for ultra-low temperature media transportation according to claim 1, wherein: a rotating assembly is arranged between the upper rotating joint and the lower rotating joint and comprises a bearing, a first bearing jacket and a second bearing jacket, the first bearing jacket is annularly fixed at the bottom of the upper rotating joint, the second bearing jacket is annularly fixed at the top of the lower rotating joint, the first bearing jacket is arranged on the inner side of the second bearing jacket, and the bearing is arranged between the first bearing jacket and the second bearing jacket.

3. A rotary joint device for ultra-low temperature medium transportation according to claim 2, wherein: the outer edge of the bottom of the upper rotary joint extends outwards horizontally to form an upper connecting plate, the first bearing jacket is fixed on the upper connecting plate through a plurality of first pins, the outer edge of the top of the lower rotary joint extends outwards horizontally to form a lower connecting plate, the second bearing jacket is fixed on the lower connecting plate through a plurality of second pins, the outer ring wall of the first bearing jacket is arranged in a manner of being tightly attached to the inner ring wall of the second bearing jacket, a first clamping groove is formed in the outer ring wall of the first bearing jacket, a second clamping groove corresponding to the first clamping groove is formed in the inner ring wall of the second bearing jacket, and the bearing is arranged in the first clamping groove and the second clamping groove.

4. A rotary joint device for ultra-low temperature medium transportation according to claim 3, wherein: the upper rotary joint is internally fixed with a vertical second upper cavity wall, the second upper cavity wall is sleeved on the outer side of the first upper cavity wall, the lower rotary joint is internally fixed with a vertical second lower cavity wall, the second lower cavity wall is sleeved on the outer side of the first lower cavity wall, the second upper cavity wall and the second lower cavity wall are interconnected to form a second inner wall, an annular and closed low-temperature gas-phase fluid channel is formed between the second inner wall and the outer wall of the rotary joint device, and a vacuum layer is formed between the second inner wall and the first inner wall.

5. The rotary joint device for ultra-low temperature medium transportation according to claim 4, wherein the rotary joint device comprises a first connecting plate and a second connecting plateIs characterized in that: the first mentioned An upper chamber wall and the first lower chamber wall, and the second upper chamber wall and the second lower chamber wallThe cavity walls are connected through a sealing assembly respectively, the sealing assembly comprises a sealing ring and a compression spring, an annular sealing groove is formed in the bottom end face of the first upper cavity wall and the second upper cavity wall respectively, an annular accommodating groove is formed in the bottom face of the groove in the sealing groove, the sealing ring is assembled in the sealing groove in a matched mode, and the compression spring is arranged in the accommodating groove in the circumferential direction.

6. A rotary joint device for ultra-low temperature media transportation according to claim 5, wherein: and a plurality of sealing components are arranged on the first inner wall and the second inner wall respectively along the horizontal direction.