Transmission pipe

Abstract

The utility model relates to the technical field of pipelines, and provides a transmission pipe. The conveying pipe comprises an anti-corrosion layer, a heat preservation layer and a wrapping layer. Wherein the heat preservation layer is arranged outside the anti-corrosion layer, the heat preservation layer comprises a special-shaped spiral band aerogel layer and a special-shaped spiral framework, and the special-shaped spiral band aerogel layer and the special-shaped spiral framework are arranged in a mutual limiting mode; and the coating layer is arranged outside the thermal insulation layer. The carbon dioxide conveying pipe overcomes the defects that in the prior art, a carbon dioxide conveying pipe is poor in heat preservation performance, and the influence of the temperature of the external environment on liquid carbon dioxide is prone to being caused, the heat preservation performance is good, the influence of the external environment on the liquid carbon dioxide in the conveying pipe is avoided, and normal transportation of the liquid carbon dioxide is guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of pipelines, in particular to a transmission pipe. Background Art

[0002] Liquid carbon dioxide can be used to increase oil field production because it can effectively increase the efficiency of extracting crude oil from oil reservoirs. Liquid carbon dioxide is injected into the oil reservoir through injection wells and mixed with the crude oil, which can reduce the viscosity of the crude oil and make it easier to flow.

[0003] The transmission of liquid carbon dioxide needs to be carried out at a temperature below zero degrees Celsius. Normally, the transmission of liquid carbon dioxide needs to be carried out at a temperature of about -20 degrees Celsius to maintain its liquid state. Therefore, in order to ensure the normal transportation of liquid carbon dioxide, it is very important to reduce the impact of external temperature on it. However, the existing carbon dioxide transmission pipe has poor thermal insulation performance, which easily leads to the impact of the temperature of the external environment on the liquid carbon dioxide. Utility Model Content

[0004] The utility model provides a transmission pipe, which is used to solve the defect that the heat preservation performance of the carbon dioxide transmission pipe in the prior art is poor, which easily causes the temperature of the external environment to affect the liquid carbon dioxide, and achieves a good heat preservation performance, thereby avoiding the influence of the external environment on the liquid carbon dioxide inside the transmission pipe, and ensuring the normal transportation of the liquid carbon dioxide.

[0005] The utility model provides a transmission pipe, comprising:

[0006] Anti-corrosion layer;

[0007] A heat-insulating layer is arranged outside the anti-corrosion layer, the heat-insulating layer comprises a special-shaped spiral belt aerogel layer and a special-shaped spiral skeleton, and the special-shaped spiral belt aerogel layer and the special-shaped spiral skeleton are mutually limited;

[0008] The covering layer is arranged outside the thermal insulation layer.

[0009] According to a transmission pipe provided by the utility model, the anti-corrosion layer includes a first polymer material layer, a first steel wire layer is provided on the inner side of the first polymer material layer, and a second steel wire layer is provided on the outer side, the first steel wire layer and the second steel wire layer are both coated with the second polymer material layer on the outside, and the structures of the first steel wire layer and the second steel wire layer both include a first spiral structure.

[0010] According to a transmission tube provided by the utility model, the first steel wire layer and the second steel wire layer are staggered.

[0011] According to a transmission tube provided by the utility model, the first polymer material layer is provided with a sealing layer, a tensile layer and a structural bearing layer in sequence from the inside to the outside, the sealing layer is arranged on a side close to the first steel wire layer, and the structural bearing layer is arranged on a side close to the second steel wire layer.

[0012] According to a transmission tube provided by the utility model, the special-shaped spiral belt aerogel layer is in a second spiral structure and is arranged outside the first polymer material layer, and the special-shaped spiral skeleton is limited to the outside of the second steel wire layer.

[0013] According to a transmission tube provided by the utility model, the special-shaped spiral skeleton is a third spiral structure, the third spiral structure is arranged at a hollowed-out portion of the second spiral structure, and a cavity is arranged inside the special-shaped spiral skeleton.

[0014] According to a transmission tube provided by the utility model, the end surface of the special-shaped spiral skeleton is a plane.

[0015] According to a transmission tube provided by the utility model, a contact surface between the special-shaped spiral skeleton and the second steel wire layer is provided with a limiting portion, and the second steel wire layer is limited at the limiting portion.

[0016] According to a transmission tube provided by the utility model, the special-shaped spiral skeleton comprises a carbon fiber special-shaped spiral skeleton.

[0017] According to a transmission tube provided by the utility model, the coating layer is a third polymer material layer.

[0018] The above one or more technical solutions in the embodiments of the utility model have at least one of the following technical effects:

[0019] The utility model arranges the special-shaped spiral aerogel layer outside the first polymer material layer. The special-shaped spiral aerogel layer is a material with low thermal conductivity and excellent thermal insulation performance, thereby effectively isolating the influence of the temperature of the external environment on the transmission pipe, improving the thermal insulation effect, and keeping the liquid carbon dioxide in a low temperature state, which is convenient for its transportation.

[0020] Furthermore, the special-shaped spiral aerogel layer has an extremely low density, is light and soft, and is easy to construct and install. The special-shaped spiral aerogel layer is arranged on the outside of the insulation pipe without adding additional load, which is conducive to construction and transportation. The special-shaped spiral aerogel layer is also an environmentally friendly material, does not contain harmful substances, and is more green and environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 It is an exploded view of the transmission tube provided by the utility model;

[0023] Figure 2 It is an assembly diagram of the transmission pipe provided by the utility model;

[0024] Figure 3 yes Figure 2 Enlarged view of point A in the middle;

[0025] Figure 4 This is an exploded view of the anti-corrosion layer of the transmission pipe provided by the utility model;

[0026] Figure 5 It is a cross-sectional view of the first polymer material layer of the transmission tube provided by the utility model;

[0027] Figure 6 It is an exploded view of the support layer of the transmission pipe provided by the utility model;

[0028] Figure 7 yes Figure 6 Enlarged view of point B in the middle.

[0029] Reference numerals:

[0030] 100: anti-corrosion layer; 110: first steel wire layer; 120: first polymer material layer; 121: sealing layer; 122: tensile layer; 123: structural bearing layer; 130: second steel wire layer;

[0031] 200: insulation layer; 210: special-shaped spiral belt aerogel layer; 220: special-shaped spiral skeleton; 221: cavity; 222: limit part;

[0032] 300: Coating layer. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be described clearly and completely in conjunction with the drawings in the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0034] In the description of the embodiments of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "first" and "second" are numbered for the purpose of clearly explaining the product components and do not represent any substantial difference. The directions of "upper" and "lower" shall be based on the directions shown in the accompanying drawings. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to the specific circumstances. In addition, the meaning of "multiple" is two or more. In the specification, "and / or" means at least one of the connected objects, and the character " / " generally indicates that the related objects before and after are in an "or" relationship.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] Figure 1 An exploded view of a transmission tube provided by an embodiment of the utility model is illustrated; Figure 2 An assembly diagram of a transmission tube provided by an embodiment of the utility model is illustrated; Figure 3 Example Figure 2 Enlarged view of point A in the middle; Figure 6 An exploded view of a support layer of a transmission tube provided in an embodiment of the utility model is illustrated.

[0037] Reference Figure 1 , Figure 2 , Figure 3 and Figure 6 The transmission pipe provided by the embodiment of the utility model includes an anti-corrosion layer 100, a heat-insulating layer 200 and a coating layer 300. The heat-insulating layer 200 is arranged outside the anti-corrosion layer 100, and the heat-insulating layer 200 includes a special-shaped spiral belt aerogel layer 210 and a special-shaped spiral skeleton 220, and the special-shaped spiral belt aerogel layer 210 and the special-shaped spiral skeleton 220 are mutually limited; the coating layer 300 is arranged outside the heat-insulating layer 200.

[0038] In the above structure, the anti-corrosion layer 100, the heat-insulating layer 200 and the coating layer 300 are all arranged as a tubular structure. The anti-corrosion layer 100, the heat-insulating layer 200 and the coating layer 300 are arranged in sequence from the inside to the outside, and the three are connected in sequence. The connection between the three can be connected by a thermoplastic process or by bonding with glue. It is only necessary to make the three form a complete pipe body.

[0039] The utility model arranges the special-shaped spiral aerogel layer 210 on the outside of the first polymer material layer 120. The special-shaped spiral aerogel layer 210 is a material with low thermal conductivity and excellent thermal insulation performance, which can effectively reduce the transmission of heat, reduce heat loss, and improve the thermal insulation effect, so that the liquid carbon dioxide can be in a low-temperature state, which is convenient for its transportation. Secondly, the special-shaped spiral aerogel layer 210 has an extremely low density, is light and soft, and is easy to construct and install. Arranging the special-shaped spiral aerogel layer 210 on the outside of the insulation pipe will not add additional load, which is beneficial to construction and transportation. Furthermore, the special-shaped spiral aerogel layer 210 is an environmentally friendly material, does not contain harmful substances, and is more green and environmentally friendly.

[0040] In the above structure, the special-shaped spiral skeleton 220 limits the special-shaped spiral belt aerogel layer 210. Since the aerogel is relatively soft, it cannot be accurately fixed on the pipeline. In addition, when the vulcanization layer is coated with rubber or the polymer material is coated by an extruder, the aerogel will be deformed due to external pressure, resulting in uneven thickness of the aerogel and loss of thermal insulation effect. At this time, the special-shaped spiral skeleton 220 can effectively limit the deformation of the aerogel.

[0041] It should be noted that the shaped spiral aerogel layer 210 and the shaped spiral skeleton 220 are cross-set, and the outer sides of the two are flush. By setting the outer sides of the shaped spiral aerogel layer 210 and the shaped spiral skeleton 220 flush, the thickness and coverage area of ​​the thermal insulation layer can be effectively increased, thereby improving the thermal insulation effect and reducing heat loss. Secondly, it can also ensure that the shaped spiral aerogel layer 210 and the shaped spiral skeleton 220 are uniformly stressed, avoiding deformation or damage of the thermal insulation layer due to excessive local stress, and improving the stability and durability of the thermal insulation system. Furthermore, the flush setting can reduce the unevenness of the thermal insulation layer 200, thereby reducing the gap between the thermal insulation layer 200 and the coating layer 300, making the connection between the thermal insulation layer 200 and the coating layer 300 tighter.

[0042] Figure 4 An exploded view of the anti-corrosion layer of the transmission pipe provided by an embodiment of the utility model is illustrated.

[0043] Reference Figure 4 In some embodiments of the utility model, the anti-corrosion layer 100 includes a first polymer material layer 120, a first steel wire layer 110 is provided on the inner side of the first polymer material layer 120, and a second steel wire layer 130 is provided on the outer side. The first steel wire layer 110 and the second steel wire layer 130 are both coated with the second polymer material layer on the outside, and the structures of the first steel wire layer 110 and the second steel wire layer 130 are both first spiral structures.

[0044] This embodiment provides a first polymer material layer 120, thereby improving the corrosion resistance of the inner wall of the transmission pipe, thereby preventing the corrosion of the transmission pipe by carbon dioxide and extending the service life of the transmission pipe. The first steel wire layer 110 and the second steel wire layer 130 are respectively provided on both sides of the first polymer material layer 120, thereby increasing the strength and rigidity of the pipeline, improving the pressure resistance and deformation recovery ability of the pipeline, and reducing the risk of deformation and breakage of the pipeline during transportation and use. Secondly, the first steel wire layer 110 and the second steel wire layer 130 can also increase the tensile and compression resistance of the pipeline, so that the pipeline can maintain a stable shape when subjected to external tension or pressure, reducing the risk of breakage. Furthermore, the utility model is coated with a second polymer material layer on the outside of the first steel wire layer 110 and the second steel wire layer 130, which can further enhance the corrosion resistance of the utility model.

[0045] It should be noted that when the first steel wire layer 110 and the second steel wire layer 130 are coated with the second polymer material layer, it can be coated by a thermoplastic tube or a vulcanization process. The first polymer material layer and the second polymer material layer mentioned above can be the same polymer material or different polymer materials. The polymer materials of the first polymer material layer and the second polymer material layer include polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyester, polycarbonate, polyether, polyamide, polyimide, polyurethane, etc. Through these materials, the utility model can have excellent physical and chemical properties, including high hardness, high strength, high toughness, high heat resistance, corrosion resistance, insulation, etc., thereby greatly extending the service life of the utility model.

[0046] It can be understood that the first steel wire layer 110 and the second steel wire layer 130 are springs made of steel wire, and the parameters of the two can be the same or different, and can be specifically designed accordingly according to the actual situation. In this embodiment, by setting the first steel wire layer 110 and the second steel wire layer 130 to a spiral structure, on the one hand, the spiral structure can increase the pressure resistance of the conveying pipe, so that it can withstand greater pressure and maintain the stability of the pipeline. Secondly, the spiral structure can enable the conveying pipe to maintain a certain flexibility, adapt to different bending and torsion conditions, reduce the deformation and fatigue damage of the conveying pipe during use, and then design the utility model as a hose, so as to facilitate laying and use. Furthermore, the spiral structure can enhance the tensile resistance of the conveying pipe and prevent the conveying pipe from breaking or deforming when subjected to tension. Reduce the risk of bursting of the conveying pipe due to pressure and improve the safety of the conveying pipe.

[0047] The method of fixing the first steel wire layer 110 and the second steel wire layer 130 on both sides of the first polymer material layer 120 can use a special adhesive to bond the first steel wire layer 110 and the second steel wire layer 130 to both sides of the first polymer material layer 120. It should be noted that this method requires the selection of a suitable adhesive to ensure that the structural layer is firmly bonded to the first polymer material layer 120, thereby increasing the overall strength of the hose. Furthermore, the first steel wire layer 110 and the second steel wire layer 130 can also be fixed to the first polymer material layer 120 by hot pressing. This method can ensure that the structural layer is firmly adhered to the first polymer material layer 120, so that the structural layer is tightly combined with the first polymer material layer 120, is not easy to fall off or shift, and forms a solid overall structure.

[0048] Reference Figure 4 In some embodiments of the present invention, the first steel wire layer 110 and the second steel wire layer 130 are staggered.

[0049] It is understandable that since both the first steel wire layer 110 and the second steel wire layer 130 are spiral structures, they are provided with hollow parts, and the first steel wire layer 110 and the second steel wire layer 130 are staggered, that is, the first steel wire layer 110 and the hollow parts of the second steel wire layer 130 are arranged correspondingly, and the second steel wire layer 130 and the hollow parts of the first steel wire layer 110 are arranged correspondingly. By staggering the first steel wire layer 110 and the second steel wire layer 130, the overall structure of the pipeline can be made more uniform, and the stability and bearing capacity of the pipeline can be increased. The pipeline is made more flexible when subjected to bending and torsion, and the risk of deformation and fatigue damage of the pipeline is reduced. Secondly, the staggered spiral structure can also improve the tensile resistance of the pipeline, reducing the risk of the pipeline breaking or deforming when subjected to tension.

[0050] Figure 5 A cross-sectional view of the first polymer material layer of the transmission tube provided by an embodiment of the utility model is illustrated.

[0051] Reference Figure 5 In some embodiments of the utility model, the first polymer material layer 120 is provided with a sealing layer 121, a tensile layer 122 and a structural bearing layer 123 from the inside to the outside, the sealing layer 121 is arranged on the side close to the first steel wire layer 110, and the structural bearing layer 123 is arranged on the side close to the second steel wire layer 130.

[0052] The first polymer material layer 120 is provided with a sealing layer 121, a tensile layer 122 and a structural bearing layer 123 from the inside to the outside. Among them, the sealing layer 121 can effectively prevent the leakage of liquid carbon dioxide, improve the sealing performance of the transmission pipe, thereby reducing the risk of leakage and ensuring the safe operation of the transmission pipe. The tensile layer 122 can enhance the tensile resistance of the pipeline, so that it can withstand greater tension, reducing the risk of fracture or deformation of the transmission pipe during transportation and use. The structural bearing layer 123 can disperse the stress inside the pipeline, reduce the stress concentration generated when the pipeline is under pressure, and improve the stability and pressure resistance of the pipeline.

[0053] Among them, the sealing layer 121 is made of a material with good chemical corrosion resistance, wear resistance and good elastic recovery. Its materials include polytetrafluoroethylene, fluororubber, silicone rubber, etc. In the actual application process, the sealing layer 121 can be set as a single layer or multiple layers to ensure effective sealing performance. The tensile layer 122 is made of a material with high tensile strength and elastic modulus to enhance the tensile resistance of the pipeline. Its materials include polyester fiber, aramid fiber, carbon fiber, etc. The structure of the tensile layer 122 can be a woven structure, a grid structure or a laminated structure, which can improve its mechanical properties. The structural bearing layer 123 is made of a material with good pressure resistance and rigidity to disperse the stress inside the pipeline and improve the stability of the pipeline. Its materials include glass fiber reinforced materials, carbon fiber reinforced materials, etc. It should be noted that the structure of 133 can also be a composite material structure to improve its rigidity and pressure resistance.

[0054] The connection method between the sealing layer 121, the tensile layer 122 and the structural bearing layer 123 can be specifically: ① Bonding: Use appropriate high-strength adhesive or glue to bond the sealing layer 121, the tensile layer 122 and the structural bearing layer 123 to form a whole. This connection method can provide better connection strength and sealing. ② Hot melt: For some special polymer materials, hot melt can be used to connect the layers. It is partially melted by heating and then solidified by cooling, thereby achieving the connection between the layers.

[0055] Figure 7 Example Figure 6 Enlarged view of point B in the middle.

[0056] Reference Figure 6 and Figure 7 In some embodiments of the present invention, the special-shaped spiral belt aerogel layer 210 is in a second spiral structure and is arranged outside the first polymer material layer 120 , and the special-shaped spiral skeleton 220 is limited to the outside of the second steel wire layer 130 .

[0057] The special-shaped spiral skeleton 220 is a third spiral structure, and the third spiral structure is arranged in the hollowed-out part of the second spiral structure. A cavity 221 is arranged inside the special-shaped spiral skeleton 220 .

[0058] By setting a cavity 221 inside the special-shaped spiral skeleton 220, the special-shaped spiral skeleton 220 is constructed into a hollow structure, and the hollow structure can reduce heat conduction, because air is a poor heat conductor, making it difficult for heat to be conducted in the special-shaped spiral skeleton 220, thereby improving the thermal insulation effect. It is then complementary to the special-shaped spiral belt aerogel layer 210, and the areas that the special-shaped spiral belt aerogel layer 210 cannot cover are insulated. Secondly, the hollow design can reduce the weight of the special-shaped spiral skeleton 220, making the entire structure lighter and easier to construct and install. Compared with a solid structure, the hollow special-shaped spiral skeleton 220 can save materials while still maintaining sufficient strength and stability, thereby reducing costs.

[0059] Reference Figure 6 In some embodiments of the present invention, the end face of the special-shaped spiral skeleton 220 is a plane. It can be understood that the cross-street surface of the special-shaped spiral skeleton 220 is a rectangular structure, and its upper and lower sides are both flat structures. This design will make the final surface of the transmission tube relatively flat, which is convenient for the transportation of the transmission tube.

[0060] Reference Figure 7 In some embodiments of the present invention, the contact surface between the special-shaped spiral skeleton 220 and the second steel wire layer 130 is provided with a limiting portion 222, and the second steel wire layer 130 is limited at the limiting portion 222. By providing the limiting portion 222, it is ensured that the special-shaped spiral skeleton 220 and the second steel wire layer 130 maintain a relatively stable position when subjected to force, preventing the spring from unnecessary displacement during movement or vibration, thereby improving stability and reliability.

[0061] In some embodiments of the utility model, the special-shaped spiral skeleton 220 comprises a carbon fiber special-shaped spiral skeleton. Specifically, the special-shaped spiral skeleton 220 is made of carbon fiber material. Of course, the prepared material of the special-shaped spiral skeleton 220 is not limited to carbon fiber. By setting the special-shaped spiral skeleton 220 to a carbon fiber special-shaped spiral skeleton, since the carbon fiber has very high strength and rigidity and is very light in weight, the special-shaped spiral skeleton 220 can provide excellent structural strength and stability while also reducing the weight of the entire structure. Secondly, the carbon fiber has excellent corrosion resistance and is not easily corroded by moisture, chemicals or other environmental factors, so it can be used for a long time in harsh environments. Furthermore, compared with metal, carbon fiber has better fatigue characteristics, can withstand more cyclic loads and is not prone to fatigue damage, and then provides excellent rigidity and bending resistance, so that the special-shaped spiral skeleton 220 can withstand greater pressure and torque.

[0062] In some embodiments of the utility model, the coating layer 300 is a third polymer material layer. The coating layer 300 can be realized by coating the outermost side of the pipe with a vulcanized layer of rubber or a polymer material through an extruder. By setting the coating layer 300, it can not only isolate the erosion of the pipe by seawater when floating on the sea surface, but also help the pipe to improve its ability to withstand internal pressure, and also prevent abnormal wear and tear of the braided materials inside the pipe. The outermost layer of the original low-temperature pipe is a braided material, which will be worn by the ground, the coiling machine, etc. during in-situ operation, resulting in material damage, and then the pipe structure performance is damaged.

[0063] The transmission pipe provided by the utility model has good corrosion resistance, pressure resistance, heat preservation and light weight. It can not only be frequently put away and put on the disk machine, but also float on the sea surface, so as to realize the transportation of liquid carbon dioxide on the sea surface over long distances, and can meet the demand for low-temperature transmission of liquid carbon dioxide.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A transmission tube, characterized in that: include: Anti-corrosion layer (100); A thermal insulation layer (200) is arranged outside the anti-corrosion layer (100), the thermal insulation layer (200) comprising a special-shaped spiral belt aerogel layer (210) and a special-shaped spiral skeleton (220), the special-shaped spiral belt aerogel layer (210) and the special-shaped spiral skeleton (220) being arranged to limit each other; The coating layer (300) is arranged outside the thermal insulation layer (200).

2. The transmission tube according to claim 1, characterized in that: The anti-corrosion layer (100) comprises a first polymer material layer (120), a first steel wire layer (110) is provided on the inner side of the first polymer material layer (120), and a second steel wire layer (130) is provided on the outer side, the first steel wire layer (110) and the second steel wire layer (130) are both coated with the second polymer material layer on the outside, and the structures of the first steel wire layer (110) and the second steel wire layer (130) both comprise a first spiral structure.

3. The transmission tube according to claim 2, characterized in that: The first steel wire layer (110) and the second steel wire layer (130) are arranged in a staggered manner.

4. The transmission tube according to claim 2, characterized in that: The first polymer material layer (120) is provided with a sealing layer (121), a tensile layer (122) and a structural bearing layer (123) in sequence from the inside to the outside, the sealing layer (121) is provided on a side close to the first steel wire layer (110), and the structural bearing layer (123) is provided on a side close to the second steel wire layer (130).

5. The transmission tube according to claim 2, characterized in that: The special-shaped spiral belt aerogel layer (210) is in a second spiral structure and is arranged outside the first polymer material layer (120), and the special-shaped spiral skeleton (220) is limited to the outside of the second steel wire layer (130).

6. The transmission tube according to claim 5, characterized in that: The special-shaped spiral skeleton (220) is a third spiral structure, and the third spiral structure is arranged at a hollowed-out portion of the second spiral structure. A cavity (221) is arranged inside the special-shaped spiral skeleton (220).

7. The transmission tube according to claim 5, characterized in that: The end surface of the special-shaped spiral skeleton (220) is a plane.

8. The transmission tube according to claim 5, characterized in that: A contact surface between the special-shaped spiral skeleton (220) and the second steel wire layer (130) is provided with a limiting portion (222), and the second steel wire layer (130) is limited at the limiting portion (222).

9. The transmission tube according to any one of claims 5 to 8, characterized in that: The special-shaped spiral skeleton (220) comprises a carbon fiber special-shaped spiral skeleton.

10. The transmission tube according to claim 9, characterized in that: The coating layer (300) is a third polymer material layer.

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