CN112709872A

CN112709872A - Double-layer pipe

Info

Publication number: CN112709872A
Application number: CN202011561142.7A
Authority: CN
Inventors: 吴敏; 彭杰峰; 徐宁; 付新
Original assignee: Zhejiang Qier Electromechanical Technology Co ltd
Current assignee: Zhejiang Qier Electromechanical Technology Co ltd
Priority date: 2020-12-25
Filing date: 2020-12-25
Publication date: 2021-04-27

Abstract

The present invention relates to a double-walled pipe. In the invention, a fluid conveying channel is formed in the inner pipe, and a heat preservation channel is formed in the space between the inner pipe and the outer pipe; the conveying channel and the heat preservation channel are communicated at the upstream end by a flow path, so that the fluid is divided into the conveying channel and the heat preservation channel; a liquid outlet is arranged at the downstream of the heat preservation channel; the fluid in the conveying channel is conveyed to a downstream user unit continuously, and the fluid in the heat preservation channel is discharged out of the double-layer pipe through the liquid outlet; the heat preservation channel is internally provided with a support body which plays a role in supporting the space height between the outer side surface of the inner pipe and the inner side surface of the outer pipe. The invention improves the capability of resisting environmental thermal interference of the conveyed fluid and is beneficial to maintaining the temperature precision in the fluid conveying process. The double-layer pipe uses fluid which is the same as the conveying fluid as a heat insulating material; the support body is arranged in the heat preservation channel, so that the uniform extension of the section of the heat preservation channel is favorably kept; is beneficial to maintaining the heat preservation performance of the heat preservation fluid.

Description

Double-layer pipe

Technical Field

The invention belongs to the technical field of fluid conveying, and relates to a double-layer pipe.

Background

In the field of precision manufacturing of semiconductors and the like, precise temperature control of fluids is often required. For example, an immersion lithography machine needs to continuously supply ultrapure water with a temperature fluctuation range of less than 0.01 ℃ to an exposure space to ensure that the optical properties of water are uniform; for another example, immersion lithography machines also use fluid flow for temperature control of the internal environment and components of the apparatus, including supplying a constant temperature water flow to the stage to maintain the stage at a temperature near 22 ℃, and supplying a lower temperature inert gas flow to the projection objective system to cool the lens. In these applications, it may be desirable for the fluid stream to have a high degree of temperature accuracy, for example, the temperature of the fluid stream fluctuates less than 0.1 ℃ or even less than 0.01 ℃ over time. Thermal disturbances in the environment during fluid delivery can reduce the temperature accuracy of the fluid, resulting in an inability to meet usage requirements after delivery of the fluid from the fluid source to the user unit.

One of the methods for solving the problem that the fluid is subjected to thermal disturbance in the conveying process is to take heat preservation measures on a fluid pipeline to reduce heat exchange between the fluid and the environment. The existing technical scheme for insulating the fluid pipeline is that the exterior of the fluid pipeline is coated with foaming materials such as polyurethane, but the coating of the foaming materials is easy to generate debris pollutants and is unfavorable in the semiconductor industry with high cleanliness; and the coating operation is easy to have the problems of uneven coating thickness, unreliable attachment and the like, and the heat insulation reliability of the fluid pipeline is reduced. An improved pipeline heat insulation scheme is that a layer of pipeline is arranged outside a fluid pipeline, and an interlayer space between the two layers of pipelines is filled with a heat insulation material (for example, a Chinese utility model patent with an authorization publication number of CN 203585592U), the method can ensure the uniformity of the heat insulation material coated outside the fluid pipeline, but the heat insulation material is usually customized, the cost is relatively high, and the method is limited by the heat insulation performance, the volume and other factors of the heat insulation material, and the occasion with high fluid temperature precision requirement can still be difficultly met.

The Chinese patent application with the publication number of CN105465554A discloses a heat-insulating double-layer pipe pipeline device for material conveying, which adopts a double-layer pipeline arrangement, wherein the inner layer pipeline is used for conveying heat-insulating materials, and circulating steam is supplied to a space between the inner layer pipeline and the outer layer pipeline to realize heat insulation of the materials. This solution improves the uniformity of the insulation performance and allows to adjust the steam supply parameters according to the insulation requirements. However, this solution requires an additional steam preparation and circulation system, and is costly.

In addition, the existing heat-insulating double-layer pipe capable of filling fluid in the heat-insulating layer generally adopts a hard pipeline with a fixed shape, and the pipeline and a corresponding joint are usually required to be customized, so that the cost is higher; and is inconvenient to use in the case of an equipment internal space or a field assembly site where the requirement for flexibility of the arrangement of the pipeline is high.

Disclosure of Invention

The invention aims to provide a double-layer pipe, wherein the double-layer fluid pipeline uses a soft pipeline, an inner pipe and an outer pipe are separated, the double-layer pipe can be conveniently assembled into the double-layer pipe according to the field condition, and the double-layer pipe is further used for heat insulation application of long-distance fluid conveying.

The heat-insulation pipe comprises an inner pipe and an outer pipe, wherein the inner pipe is positioned in the outer pipe, a fluid conveying channel is formed in the inner pipe, and a heat-insulation channel is formed in a space between the inner pipe and the outer pipe; the conveying channel and the heat preservation channel are communicated at the upstream end by a flow path, so that the fluid is divided into the conveying channel and the heat preservation channel; a liquid outlet is arranged at the downstream of the heat preservation channel; the fluid in the conveying channel is conveyed to a downstream user unit continuously, and the fluid in the heat preservation channel is discharged out of the double-layer pipe through the liquid outlet; the heat preservation channel is internally provided with a support body which plays a role in supporting the space height between the outer side surface of the inner pipe and the inner side surface of the outer pipe.

The inner tube and the outer tube are made of soft materials.

The inner and outer tube materials comprise fluoroplastic.

The outer side wall surface of the inner pipe extends outwards to form the supporting bodies, the supporting bodies are provided with intervals in the circumferential direction, and the intervals between the supporting bodies extend in the axial direction to form through spaces.

And a gap is formed between the outer side surface of the support body and the inner side surface of the appearance.

The radial inner width of the support body is greater than the radial outer width.

The support body is discontinuous in the axial direction.

The support body is in a trapezoidal boss structure with a wide radial inner side and a narrow radial outer side.

The supporting bodies are connected by the connectors to form supporting pipes, and the supporting pipes are arranged in the space between the inner pipe and the outer pipe.

The connector includes weft connector and warp connector, and the supporter is connected and keeps certain interval through the weft connector in circumference, and the supporter is connected and keeps certain interval through the warp connector in the axial.

By using the double-layer pipe provided by the invention, the insulating layer is arranged to wrap the outside of the conveyed fluid, so that the capability of resisting environmental thermal interference of the conveyed fluid can be improved, and the temperature precision in the fluid conveying process can be kept. The double-layer pipe uses fluid which is the same as the conveying fluid as a heat insulation material, and does not need additional heat insulation fluid and a matched supply system; the heat preservation fluid is continuously updated, so that the heat preservation fluid has the temperature closest to the temperature of the conveying fluid, and the heat preservation performance of the heat preservation fluid is favorably maintained. The support body is arranged in the heat preservation channel, so that the section of the heat preservation channel at the bent part of the double-layer pipe cannot be obviously changed, the uniform extension of the section of the heat preservation channel is favorably kept, and the heat preservation performance of heat preservation fluid is favorably maintained.

Drawings

FIG. 1 is a schematic structural diagram according to a first embodiment of the present invention;

FIG. 2 is a schematic right-view structural diagram according to a first embodiment of the present invention;

FIG. 3 is a schematic structural diagram according to a second embodiment of the present invention;

FIG. 4 is a schematic view of an A-tube joint structure according to a third embodiment of the present invention;

FIG. 5 is a schematic view of a joint structure of a B-type pipe according to a third embodiment of the present invention;

FIG. 6 is a schematic view of a joint structure of a B-type pipe according to a third embodiment of the present invention;

fig. 7 is a method of mounting a pipe joint according to a third embodiment of the present invention;

FIG. 8 is a schematic view showing the contact of the soft double-layer tube at the bending position;

FIG. 9 is a schematic structural diagram of a fifth embodiment of the present invention;

FIG. 10 is an assembled view of a fifth embodiment of the present invention;

FIG. 11 is an assembled view of a fifth embodiment of the present invention;

FIG. 12 is a schematic structural diagram of a sixth embodiment of the present invention;

FIG. 13 is a schematic structural view of a support according to a sixth embodiment of the present invention;

fig. 14 is a schematic structural diagram of a seventh embodiment of the present invention.

Detailed Description

Example one

As shown in fig. 1 and 2, a double tube 1A includes an inner tube 13 and an outer tube 15, the inner tube 13 being located inside the outer tube 15, the inner tube 13 and the outer tube 15 being substantially equal in length; a conveying channel 14 for fluid is formed inside the inner pipe 13, and a heat preservation channel 16 is formed in the space between the inner pipe 13 and the outer pipe 15; the heat preservation channel 16 is provided with a conveying inlet 11 at the upstream and a conveying outlet 12 at the downstream; the upstream of the inner pipe 13 is provided with an inner through hole 161 and an outer through hole 161, and the inner through hole 161 is communicated with the conveying channel 14 and the heat preservation channel 16; a drain 162 is provided downstream of the incubation passage 16, and the drain 162 has a drain opening 163 for discharging the fluid in the incubation passage 16 to the outside of the pipe.

After the conveyed fluid enters the double-layer pipe 1A through the conveying inlet 11, a part of the fluid flows downstream along the conveying channel 14 and flows out of the double-layer pipe 1A through the conveying outlet 12; the other part of the fluid enters the heat preservation channel 16 through the inner and outer through holes 161, flows downstream along the heat preservation channel 16 and is discharged out of the heat preservation channel 16 through the liquid discharge port 163. The fluid in the heat-preserving channel 16 is subjected to a thermal disturbance from the external environment to generate a temperature change, the amplitude of the temperature change gradually decreases inwards along the radial direction of the pipeline, so that the fluid in the heat-preserving channel 16 close to the inner pipe 13 has a smaller temperature change amplitude; because the inner pipe obstructs convection between the fluids in the conveying channel 14 and the heat preservation channel 16, the path of the environmental thermal disturbance influencing the temperature of the fluid in the conveying channel 14 through thermal convection is weakened, and the temperature maintenance of the fluid in the conveying channel 14 is facilitated; downstream of the double tube 1A, the fluid in the insulated channel 16 has a lower temperature accuracy than the fluid in the delivery channel 14, and the fluid in the delivery channel 14 is delivered to the downstream user unit, and the fluid in the insulated channel 16 is discharged. The fluid in the heat preservation channel 16 is enabled to be continuously updated, the situation that the fluid in the heat preservation channel 16 continuously accumulates environmental thermal interference to form temperature drift can be avoided, the temperature difference of the fluid in the heat preservation channel 16 and the fluid in the conveying channel 14 can be reduced, and the heat preservation of the fluid in the conveying channel 14 can be facilitated. Since the fluid in the incubation channel 16 and the delivery channel 14 are from the same source, no additional incubation fluid supply circulation system is required; the temperature of the holding channel 16 is the same temperature as the fluid in the transfer channel 14 upstream of the double tube 1A, with minimal thermal interference with the fluid in the transfer channel 14, and without the need to match the temperature of the holding fluid and the transfer fluid. Therefore, the invention obtains good heat preservation performance to the conveying fluid and improves the capability of resisting external heat interference under the condition of not configuring an additional heat preservation fluid supply system.

The sizes and the numbers of the openings of the upstream inner and outer through holes 161 and the downstream liquid discharge port 163 of the double-layer pipe 1A and the sectional area of the heat preservation channel 16 are changed, so that the proportion of the flow rates of the fluids in the heat preservation channel 16 and the conveying channel 14 can be changed, and different heat preservation performances of the conveyed fluids can be obtained.

Example two

As shown in fig. 3, a double tube 1B, the upstream of the inner tube 13 extends to a position further than the outer tube 15; a drainage end 165 is arranged at the upstream of the inner pipe 13, a drainage port 166 is arranged in the drainage end 165, and the drainage end 165 can be a structural feature of the inner pipe 13 or a structural feature which is added to the inner pipe 13 in the form of a tee joint and the like; the inner and outer through holes 161 are not directly connected to the conveyance path 14 and the heat-insulating path 16; the drainage port 166 communicates with the inner and outer through holes 161 through a drainage tube 167 to drain the fluid in the transfer passage 14 to the warming passage 16. The remaining embodiments are the same as the first double tube embodiment.

This embodiment allows for more flexibility in placing the vents 166, as compared to the first dual tube embodiment, facilitating assembly of the dual tube; meanwhile, the structure of the inner pipe is simpler, and the double-layer pipe is convenient to manufacture.

EXAMPLE III

As shown in fig. 4 and 5, a double pipe is assembled by connecting an inner pipe 13 and an outer pipe 15 using a coupling 2; specifically, an a-type pipe joint 2A is used at the upstream end, and a B-type pipe joint 2B is used at the downstream end.

Fig. 4 shows an a-type pipe joint 2A, the a-type pipe joint 2A has an external joint 21, an internal pipe joint 22 and an external pipe joint 23 extending from the base body, and respectively connects the upstream pipe 131, the internal pipe 13 and the external pipe 15, the internal pipe joint 22 is located at the radial inner side of the external pipe joint 23, and the internal and external through holes 161 are formed on the wall surface of the internal pipe joint 22 to communicate with the conveying channel 14 and the heat preservation channel 16; the connection mode of each joint and each pipe can adopt the existing pipe connection technology, for example, in the embodiment, the external joint 21, the internal pipe joint 22 and the external pipe joint 23 are all provided with a zigzag structure to form a pagoda head 24; and sleeving hoses such as PP pipes on the pagoda head 24, applying pressure or applying pressure after heating to enable the hoses to be subjected to plastic deformation and be nested with the pagoda head 24, and completing connection and sealing of the pipes and the joints.

FIGS. 5 and 6 show a type B pipe joint 2B, wherein one drainage joint 25 is arranged on the type B pipe joint 2B relative to the type A pipe joint 2B for connecting with a drainage pipe 167; a drainage channel 251 is arranged in the B-shaped pipe joint 2B, and the drainage pipe 167 is communicated with the inner through hole 161, the outer through hole 161 and the heat preservation channel 16; the inner and outer through holes 161 may be provided in the form of circumferentially uniformly distributed openings; the inner tube fitting 22 is arranged to extend further relative to the base than the outer tube fitting 23, with the pagoda head of the inner tube fitting 22 exposed beyond the outer tube fitting 23.

By adopting the pipe joint 2A and the pipe joint 2B of the embodiment, the drainage joint 25 of the pipe joint 2B of the B type is used for draining liquid, and the simple single-layer pipeline is connected in the above manner, so that the double-layer pipe equivalent to the first embodiment of the double-layer pipe of the invention can be obtained.

When the pipe joint is connected to the pipe as shown in fig. 7, the inner pipe 13 is placed inside the outer pipe 15 as shown in fig. 7(a), the inner pipe 13 is moved so that its end portion protrudes from the inside of the outer pipe 15, and the inner pipe joint 22 and the inner pipe 13 are connected; moving the outer pipe 15 to enable the end part of the outer pipe to be sleeved on the outer pipe joint 23, and connecting the outer pipe joint 23 and the outer pipe 15; connecting the upstream pipe 131 and the external joint 131; and completing the connection of the A-type pipe joint 2A and the pipeline. The connection method of the B-type pipe joint 2B to the pipeline is similar to that of the a-type pipe joint 2A.

The double-layer pipes with different lengths can be conveniently assembled by adopting the connection mode of the pipe joint and the single-layer pipe, the double-layer pipe can be conveniently assembled in site construction, the special double-layer pipe does not need to be customized, and the use is more convenient.

In the fourth embodiment, a B-type pipe joint 2B is used at the upstream and downstream of the pipeline, the drainage joint 25 of the upstream B-type pipe joint 2B is used for drainage, the drainage joint 25 of the downstream B-type pipe joint 2B is used for drainage, and the inner pipe 13 and the outer pipe 15 are connected to obtain the double-layer pipe corresponding to the second embodiment of the double-layer pipe of the invention. Compared to the third embodiment, this embodiment can reduce one kind of pipe joint configuration.

EXAMPLE five

The double-layer pipe according to the present invention may be formed by using a hard material that is not easily twisted and bent as the material of the inner pipe 13 and the outer pipe 15, or may be formed by using a soft material that is easily twisted and bent as the material of the inner pipe 13 and the outer pipe 15. The use of the soft material pipeline allows the pipeline to be twisted and bent, and is particularly convenient to use in equipment with small space size or when a pipeline system is assembled and built on site. In addition, in the field of semiconductor industry and the like, it is often required to introduce as few contaminants as possible when transporting fluids, and fluoroplastics such as fusible Polytetrafluoroethylene (PFA) are piping materials that meet such high cleanliness requirements, and many piping made of fluoroplastics are soft.

As shown in fig. 8, in the double-layer pipe assembled by using soft materials, the bending curvatures of the inner pipe 13 and the outer pipe 15 may be inconsistent at the bending position 40, and further, the wall surface of the outer pipe 15 may be close to or even contact with the wall surface of the inner pipe 13, so that the cross section of the heat preservation channel 16 changes along the fluid flow direction. The cross section of the heat preservation channel 16 changes, on one hand, the flow resistance to the heat preservation fluid is increased, and on the other hand, the heat preservation function of the heat preservation fluid on the side of the wall surface contact is weakened due to the fact that the thickness of the heat preservation fluid is reduced, so that the double-layer pipe formed by assembling soft materials possibly has the problem that the heat preservation performance of conveyed fluid is reduced due to the fact that the pipeline is bent.

As shown in fig. 9, in an embodiment of the double tube according to the present invention, the inner tube 13 has a structure shown in fig. 9(a), and the outer tube 15 has a structure shown in fig. 9 (b); the outer side wall surface of the inner pipe 13 extends outwards to form supporting bodies 30, the supporting bodies 30 are provided with intervals in the circumferential direction, and the intervals between the supporting bodies 30 extend in the axial direction to form through spaces; as shown in fig. 10 and 11, the inner tube 13 is placed in the outer tube 15 to obtain a double-layer tube, the outer side surface 301 of the support body is close to or in contact with the inner side surface of the outer tube 15, and preferably, a narrow gap is formed between the outer side surface 301 of the support body and the inner side surface of the outer tube 15 to facilitate the sleeved assembly of the inner tube and the outer tube; the support bodies 30 support the inner pipe 13 and the outer pipe 15, so that the outer side surface of the inner pipe 13 is prevented from contacting with the inner side surface of the outer pipe 15 at the bent position, and the interval between the support bodies 30 allows the heat preservation fluid to flow. The arrangement of the supporting body 30 ensures that the cross section of the heat-insulating channel 16 does not change basically along the pipeline path, which is beneficial to ensuring the heat-insulating performance of the double-layer pipe. The other embodiments are the same as any one of the first to fourth embodiments.

Preferably, the supporting body 30 is a trapezoidal boss structure with a radial inner width L1 greater than a radial outer width L2, which is beneficial to maintaining the upright state of the supporting body 30, reducing the stress concentration phenomenon at the corners of the structure, and simultaneously reducing the width of the outer side surface 301 of the supporting body so as to reduce the assembling resistance.

EXAMPLE six

As shown in fig. 12, in the double tube, the support body 30 of the inner tube 13 is discontinuous in the axial direction, so that the tensile stress of the support body 30 in the axial direction when the inner tube 13 is bent is reduced, and the bending of the inner tube 13 is facilitated. Preferably, as shown in fig. 13, the supporting body 30 has a trapezoidal boss structure with a radially inner side being wide and a radially outer side being narrow, which is beneficial to reducing the stress concentration phenomenon at the corner of the structure and also beneficial to reducing the flow resistance of the heat preservation fluid. The other implementation modes are the same as the fifth embodiment.

EXAMPLE seven

As shown in fig. 13, a double-walled tube includes an inner tube 13, an outer tube 15, and a support tube 31; the supporting tube 31 and the outer tube 15 are sleeved outwards in sequence along the radial direction of the inner tube 13; the inner and

outer tubes

13, 15 are simple straight tubes; the support tube 31 includes support bodies 30 and connectors 32, the support bodies 30 are disposed in a space between the inner tube 13 and the outer tube 15, and the connectors 32 connect a plurality of the support bodies 30 and keep the support bodies 30 at certain intervals; preferably, the support bodies 30 are maintained at intervals in both the circumferential and axial directions. The other embodiments are the same as any one of the first to fourth embodiments.

Preferably, the supporting bodies 30 are connected and kept at a certain interval by the weft connecting bodies 321 in the circumferential direction and connected and kept at a certain interval by the warp connecting bodies 322 in the axial direction, so that the space occupied by the connecting bodies 32 can be reduced, the space occupied by the heat-insulating fluid can be increased, the flow of the heat-insulating fluid is facilitated, and the heat-insulating performance can be improved; and the weight of the double-layer pipe is reduced, which is beneficial to the assembly of the double-layer pipe.

The supporting tube 31 is adopted to support the space between the inner tube 13 and the outer tube 15, so that the inner tube 13 is separated from the supporting body 30, various types of inner tubes 13 and outer tubes 15 can be assembled conveniently according to actual assembly conditions to obtain a double-layer tube, and assembly is facilitated.

In the positional relationship description of the present invention, the appearance of terms such as "inner", "outer", "upper", "lower", "left", "right", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the drawings is merely for convenience of describing the embodiments and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation and operation, and thus, is not to be construed as limiting the present invention.

The foregoing summary and structure are provided to explain the principles, general features, and advantages of the product and to enable others skilled in the art to understand the invention. The foregoing examples and description have been presented to illustrate the principles of the invention and are intended to provide various changes and modifications within the spirit and scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A double-layer pipe comprises an inner pipe and an outer pipe, and is characterized in that: the inner pipe is positioned in the outer pipe, a fluid conveying channel is formed in the inner pipe, and a heat preservation channel is formed in a space between the inner pipe and the outer pipe; the conveying channel and the heat preservation channel are communicated at the upstream end by a flow path, so that the fluid is divided into the conveying channel and the heat preservation channel; a liquid outlet is arranged at the downstream of the heat preservation channel; the fluid in the conveying channel is conveyed to a downstream user unit continuously, and the fluid in the heat preservation channel is discharged out of the double-layer pipe through the liquid outlet; the heat preservation channel is internally provided with a support body which plays a role in supporting the space height between the outer side surface of the inner pipe and the inner side surface of the outer pipe.

2. The double-walled tube of claim 1, wherein: the inner tube and the outer tube are made of soft materials.

3. The double-walled tube of claim 1, wherein: the inner and outer tube materials comprise fluoroplastic.

4. The double-walled tube of claim 1, wherein: the outer side wall surface of the inner pipe extends outwards to form the supporting bodies, the supporting bodies are provided with intervals in the circumferential direction, and the intervals between the supporting bodies extend in the axial direction to form through spaces.

5. The double-walled tube of claim 4, wherein: and a gap is formed between the outer side surface of the support body and the inner side surface of the appearance.

6. The double-walled tube of claim 4, wherein: the radial inner width of the support body is greater than the radial outer width.

7. The double-walled tube of claim 4, wherein: the support body is discontinuous in the axial direction.

8. The double-walled tube of claim 7, wherein: the support body is in a trapezoidal boss structure with a wide radial inner side and a narrow radial outer side.

9. The double-walled tube of claim 1, wherein: the supporting bodies are connected by the connectors to form supporting pipes, and the supporting pipes are arranged in the space between the inner pipe and the outer pipe.

10. The double-walled tube of claim 9, wherein: the connector includes weft connector and warp connector, and the supporter is connected and keeps certain interval through the weft connector in circumference, and the supporter is connected and keeps certain interval through the warp connector in the axial.