CN113217719A

CN113217719A - Low-temperature transmission pipeline device

Info

Publication number: CN113217719A
Application number: CN202110642666.7A
Authority: CN
Inventors: 倪东升; 朱丽; 王旭东; 王力实; 程月
Original assignee: Institute of Modern Physics of CAS
Current assignee: Institute of Modern Physics of CAS
Priority date: 2021-06-09
Filing date: 2021-06-09
Publication date: 2021-08-06

Abstract

The invention discloses a low-temperature transmission pipeline device, which comprises an outer pipe, at least one inner pipe and two end supporting plates, wherein the inner pipe is provided with a bending compensator without a corrugated pipe expansion joint, the inner pipe penetrates through the inner part of the outer pipe, and a plurality of inner pipes are separated from the outer pipe through the end supporting plates and are integrated; the bending compensator is in a bending or bending state at normal temperature, and can provide cooling compensation for the inner pipe in a low-temperature environment. According to the low-temperature transmission pipeline device disclosed by the invention, the bending compensator can provide cooling compensation for the inner pipe in a low-temperature environment so as to reduce the thermal stress of the pipeline, and further avoid the inner pipe and the welding line thereof from being pulled to crack; in addition, because the corrugated pipe expansion joint is not used, the noise and the vibration are smaller, the reliability is higher, the manufacturing cost is lower, and the corrugated pipe expansion joint is not easy to break after being deformed for many times.

Description

Low-temperature transmission pipeline device

Technical Field

The invention relates to the technical field of low-temperature transmission, in particular to a low-temperature transmission pipeline device.

Background

Cryogenic liquids such as liquid helium, liquid hydrogen, liquid nitrogen, liquid oxygen, liquefied natural gas, and liquid argon are gasified if excessive heat is absorbed during transmission, so that the cryogenic liquids need to be transmitted in cryogenic transmission pipelines. The low-temperature transmission pipeline adopts a heat insulation design, so that heat in the environment can be effectively reduced to be transferred into the low-temperature liquid, and the temperature rise and vaporization of the low-temperature liquid are reduced. The low-temperature transmission pipeline is widely applied to the fields of low-temperature or ultralow-temperature engineering such as gas engineering, scientific research, medical treatment and the like.

The existing low-temperature transmission pipeline mostly adopts a mode that an inner pipe is sleeved by an outer pipe, and because the inner pipe contracts after being reduced from room temperature to low-temperature fluid temperature and generates great thermal stress with the outer pipe, one section or a plurality of sections of corrugated pipe expansion joints (also called as metal corrugated pipe expansion joints or wave compensators, and the like, see the national standard 'metal corrugated pipe expansion joint general technical conditions' (GB/T12777-. However, as one of the compensators common to the equipment and pipeline thermal compensation technology in modern industrial production, the existence of the bellows expansion joint brings a series of problems to the existing low-temperature transmission technology:

firstly, the corrugated pipe expansion joint has an undulating corrugated structure, and when fluid passes through the corrugated pipe, the fluid is interfered by the corrugated pipe expansion joint to cause unstable flow and cause vibration and noise;

secondly, because the compensation amount of a single bellows expansion joint is limited, a plurality of bellows are required to be used in a long low-temperature transmission pipeline, so that the workload of welding and leakage detection is increased, and certain hidden troubles are left for the reliability and durability of the low-temperature transmission pipeline due to the existence of a plurality of welding lines;

thirdly, the wall thickness of the corrugated pipe is generally thin and generally less than 1 mm, so that certain influence is caused on the pressure resistance of the low-temperature transmission pipeline and the reliability of long-time work under the conditions of pressure bearing and pressure change, and the corrugated pipe has high rupture risk after being deformed for many times, which can cause the damage of the low-temperature transmission pipeline;

finally, the cost of the corrugated pipe expansion joint is higher than that of a common straight pipe, and the welding and leakage detection process of the low-temperature transmission pipe with the corrugated pipe expansion joint is more complicated, so that the cost of the low-temperature transmission pipe is increased.

Disclosure of Invention

The invention aims to provide a low-temperature transmission pipeline device, which is used for solving a series of problems of vibration/noise, low reliability, high fracture risk and the like caused by the use of a corrugated pipe in the existing low-temperature transmission technology.

The invention provides a low-temperature transmission pipeline device which comprises an outer pipe, at least one inner pipe and two end supporting plates, wherein the inner pipe is provided with a bending compensator without a corrugated pipe expansion joint, the inner pipe penetrates through the inner part of the outer pipe, and a plurality of inner pipes are separated from the outer pipe through the end supporting plates and are integrated; the bending compensator is in a bending or bending state at normal temperature, and can provide cooling compensation for the inner pipe in a low-temperature environment.

Preferably, still include the heat radiation screen, the heat radiation screen is the pipe tubular structure, the heat radiation screen is worn to locate a plurality of just the cover of the inboard of outer tube is located the outside of inner tube.

Preferably, the inner tube is one or more.

Preferably, each inner tube is provided with at least one bending compensator.

Preferably, the bending compensator is of an arc bending type or a straight bending type.

Preferably, the two end supporting plates are respectively fixed at two ends of the outer pipe and are in sealing connection with the end part of the inner pipe; the diameter of the end supporting plates is equal to the inner diameter of the outer pipe, the two end supporting plates are respectively and transversely sealed at two ends of the outer pipe to form annular sealing spaces, and the plurality of inner pipes are longitudinally arranged in the annular sealing spaces.

Preferably, a plurality of inner pipe holes are arranged on the end supporting plate, and the ends of a plurality of inner pipes are respectively and transversely sealed and penetrated in the inner pipe holes of the end supporting plate.

Preferably, when the pipeline of the cryogenic transfer pipeline device is too long, the cryogenic transfer pipeline device further comprises a plurality of sliding support plates, and the plurality of sliding support plates are arranged between the outer pipe and the inner pipe between the two end support plates at intervals.

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention discloses a low-temperature transmission pipeline device, which is characterized in that an inner pipe is provided with a bending compensator which is in a bending or bending state at normal temperature, when the inner pipe is cooled, the bending compensator precools and contracts, at the moment, an outer pipe applies reverse tension to the inner pipe to slightly straighten the inner pipe, and the bending compensator reduces the degree of arc bending or straight bending in the process of converting from a nonlinear arc bending or straight bending state to a linear state.

(2) The low-temperature transmission pipeline device disclosed by the invention has the advantages that the manufacturing process and the working procedure of the low-temperature transmission pipeline are simpler and the reliability is higher because the expansion joint of the corrugated pipe is not used.

(3) The low-temperature transmission pipeline device disclosed by the invention reduces the disturbance of the pipe wall to the fluid due to no use of the corrugated pipe expansion joint, so that the fluid flows more stably, and the noise and the vibration are smaller.

(4) The low-temperature transmission pipeline device disclosed by the invention does not need to be welded and leak-detected for many times because a corrugated pipe expansion joint is not used, the process is simpler, and the manufacturing cost is lower.

(5) Compared with the existing corrugated pipe, the low-temperature transmission pipeline device disclosed by the invention has the advantages that the inner pipe with thicker pipe wall is made of metal materials, the inner pipe is not easy to crack after being deformed for many times, and the reliability of the low-temperature transmission pipeline is improved.

Drawings

Fig. 1 is a schematic structural diagram of a cryogenic transfer pipeline apparatus according to embodiment 1 of the present invention;

FIG. 2 is a cross-sectional longitudinal view of a cryogenic transfer pipeline apparatus according to embodiment 1 of the present invention;

fig. 3 is a schematic structural view of an inner tube bending compensator according to embodiment 1 of the present invention, which is of an arc bending type;

fig. 4 is a schematic structural view of the bending compensator of the inner tube according to embodiment 1 of the present invention, which is a straight-line bending type.

Detailed Description

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

Example 1

Embodiment 1 provides a cryogenic transfer pipeline apparatus, and the structure thereof will be described in detail below.

Referring to fig. 1 and 2, the cryogenic transmission pipeline device comprises an outer pipe 1, at least one inner pipe 2 and two end support plates 3, wherein the inner pipe 2 is provided with a bending compensator 5 without a corrugated pipe expansion joint, the inner pipe 2 is arranged inside the outer pipe 1 in a penetrating manner, and the inner pipes 2 and the outer pipe 1 are separated by the end support plates 3 and are integrated. The bending compensator 5 is in a bending or bending state at normal temperature, and can provide cooling compensation for the inner pipe 2 in a low-temperature environment.

In order to prevent the outer tube to the too much heat radiation of the fluid transmission in the inner tube 2, this cryogenic transfer piping installation can also include heat radiation screen 4, and heat radiation screen 4 is the pipe tubular structure, and heat radiation screen 4 is located between outer tube 1 and the inner tube 2, specifically, heat radiation screen 4 wears to locate the inboard of outer tube 1 and the outside that a plurality of inner tubes 2 were located to the cover, heat radiation screen 4 also can with a certain inner tube between have thermal connection, provide cold volume by the inner tube and cool off.

The inner tube 2 can be one or more according to the requirement of industrial production.

According to the length of the cryogenic transfer pipeline, one bending compensator 5 can be arranged on each inner pipe 2, and a plurality of bending compensators 5 can be arranged.

As shown in fig. 3, the bend compensator 5 is of a bow type 6, i.e. the inner tube 2 located in the bend compensator 5 is of a bow type 6.

As shown in fig. 4, the bending compensator 5 is a straight bending type 7, i.e. the inner pipe 2 located in the bending compensator 5 is bent straight, i.e. the straight bending type 7.

More specifically, the bending compensator 5 is arranged on the inner tube 2, and the two end support plates 3 are respectively fixed at two ends of the outer tube 1 and are hermetically connected with the end of the inner tube 2; the diameter of the end supporting plates 3 is equal to the inner diameter of the outer pipe 1, the two end supporting plates 3 are respectively and transversely sealed at two ends of the outer pipe 1 to form annular sealing spaces, and the plurality of inner pipes 2 are longitudinally arranged in the annular sealing spaces.

In order to connect the end supporting plate 3 and the inner pipe 2, a plurality of inner pipe holes are arranged on the end supporting plate 3, and the ends of the inner pipes 2 are transversely sealed and penetrated in the inner pipe holes of the end supporting plate 3 respectively.

When the pipeline of the low-temperature transmission pipeline device is too long, the low-temperature transmission pipeline device also comprises a plurality of sliding support plates which are arranged between the outer pipe 1 and the inner pipe 2 between the two end support plates 3 at intervals.

The effect of sliding support plate is between horizontal isolation inner tube 2 and outer tube 1 and inner tube 2, avoids inner tube 2 and outer tube 1 or other inner tube 2 direct contact, reduces the conduction heat leakage between inner tube 2 and the outer tube 1 or between inner tube 2 and the inner tube 2, and wherein, sliding support plate does not play sealed effect, only plays the supporting role, if pipeline length is shorter, need not to set up sliding support plate in inside.

The inner pipe 2 can be wrapped with a plurality of layers of heat insulating materials, and the heat insulating materials are arranged on the outer side of the single inner pipe 2 or the plurality of inner pipes 2, so that the radiation heat transfer can be reduced; the two end supporting plates 3 are respectively transversely sealed at the two ends of the outer tube 1 to form annular sealing spaces which are vacuumized to be beneficial to forming a high-vacuum environment, and the convection heat transfer can be blocked by the vacuum; the end supporting plate 3 can effectively reduce heat conduction through structural optimization and selection of proper materials, so that the cryogenic transmission pipeline device is suitable for a rigid high-vacuum multilayer insulated cryogenic transmission pipeline with a single inner pipe 2 or a plurality of inner pipes 2, and the inner pipes 2 partially utilize the self rigidity of the bending compensator 5 to provide compensation.

When the inner pipe 2 is cooled, the bending compensator 5 is precooled and contracted, then the outer pipe 1 applies reverse tension to the inner pipe 2, the inner pipe 2 is slightly straightened, and the bending compensator 5 is shifted to the position of the dotted line 100 in the process of converting from the nonlinear arc bending state or the linear bending state to the linear state, and the arc bending degree or the linear bending degree is reduced, as shown in fig. 2, the bending compensator 5 is substantially the contraction process from bending to straightening, so that the length difference of the low-temperature inner pipe 2 and the room-temperature outer pipe 1 along the pipeline direction after being cooled can be exactly compensated, the thermal stress of the pipeline is reduced, and the inner pipe 2 and the welding line thereof are prevented from being pulled and cracked.

In addition, because the expansion joint of the corrugated pipe is not used, the manufacturing process and the working procedure of the low-temperature transmission pipeline device are simpler, the reliability is higher, and the manufacturing cost is also greatly reduced.

Because the inner pipe 2 positioned inside is not provided with the bellows expansion joint, the disturbance of the pipe wall to the fluid is reduced, the flow of the fluid in the inner pipe 2 is more stable, the flow of the fluid is more stable, and the noise and the vibration are less.

Because the expansion joint of the corrugated pipe is not arranged, repeated welding and leakage detection are not needed, the process is simpler, and the manufacturing cost is lower.

The inner pipe with thicker pipe wall is made of metal materials, so that the inner pipe is not easy to crack after being deformed for many times, and the reliability of the low-temperature transmission pipeline device is improved.

In conclusion, the key point of the technical scheme is that the inner pipe 2 is not provided with a bellows expansion joint, but is provided with the bending compensator 5, and the bending compensator 5 can provide compensation amount during cooling.

Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims

1. A low-temperature transmission pipeline device is characterized by comprising an outer pipe (1), at least one inner pipe (2) and two end supporting plates (3),

the inner pipe (2) is provided with a bending compensator (5) without a corrugated pipe expansion joint, the inner pipe (2) penetrates through the inner part of the outer pipe (1), and a plurality of inner pipes (2) are separated from the outer pipe (1) through the end supporting plate (3) and are integrated;

the bending compensator (5) is in a bending or bending state at normal temperature, and can provide cooling compensation for the inner pipe (2) in a low-temperature environment.

2. The cryogenic transmission pipeline device according to claim 1, further comprising a heat radiation screen (4), wherein the heat radiation screen (4) is a tubular structure, and the heat radiation screen (4) is inserted into the inner side of the outer pipe (1) and is sleeved outside the plurality of inner pipes (2).

3. The cryogenic transfer pipeline apparatus of claim 1,

the number of the inner pipes (2) is one or more.

4. The cryogenic transfer pipeline apparatus of claim 3,

each inner pipe (2) is provided with at least one bending compensator (5).

5. The cryogenic transfer pipeline apparatus of claim 4,

the bending compensator (5) is of an arc bending type (6) or a straight line bending type (7).

6. The cryogenic transfer pipe assembly of claim 1, wherein two end support plates (3) are fixed to two ends of the outer pipe (1) and are hermetically connected to the ends of the inner pipe (2); the diameter of the end supporting plates (3) is equal to the inner diameter of the outer pipe (1), the two end supporting plates (3) are respectively and transversely sealed at two ends of the outer pipe (1) to form annular sealing spaces, and the plurality of inner pipes (2) are longitudinally arranged in the annular sealing spaces.

7. The cryogenic transfer pipeline apparatus of claim 6,

the end part supporting plate (3) is provided with a plurality of inner pipe holes, and the end parts of a plurality of inner pipes (2) are respectively and transversely sealed and penetrated in the inner pipe holes of the end part supporting plate (3).

8. The cryogenic transfer pipeline device of claim 7, further comprising a plurality of sliding support plates spaced between the outer pipe (1) and the inner pipe (2) between the two end support plates (3).