Weather-proof high-strength tensile aerial insulated cable and preparation method thereof

Abstract

The invention relates to the technical field of cables, and discloses a weather-proof high-strength tensile aerial insulated cable and a preparation method thereof.The weather-proof high-strength tensile aerial insulated cable comprises a cable conductor, a protection mechanism is arranged outside the cable conductor, a supporting mechanism is arranged inside the protection mechanism, and an outer sheath is connected to the outside of the protection mechanism through a cushioning mechanism; the exterior of the cable conductor is fixedly connected with a force bearing layer, the exterior of the force bearing layer is provided with a repairing layer, the exterior of the repairing layer is fixedly connected with a heat insulation fireproof layer, the cushioning mechanism comprises an elastic rubber layer, and the inner side of the elastic rubber layer is fixedly connected to the exterior of the heat insulation fireproof layer. According to the invention, through the hollow bionic structure with the diaphragm in the core tubular bearing layer, the self weight is greatly reduced, and excellent bending resistance and torsional rigidity are provided at the same time; when the bearing layer is accidentally impacted, the internal diaphragm can effectively prevent longitudinal spreading of microcracks like a firewall, and damage is limited locally.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cables, in particular to a weather-resistant high-strength tensile overhead insulated cable and a preparation method thereof. BACKGROUND

[0002] Overhead insulated cables have been invented as early as the 1960s, and then put into use in France, Japan, the United States and other countries. The wire material covers copper, aluminum or aluminum alloy, and the insulation material uses weather-resistant polyvinyl chloride or weather-resistant polyethylene. As an overhead cable with an insulating layer wrapped outside the conductor, it has some characteristics of overhead wires and underground cables, and is a new power transmission method. It is widely used in urban and rural power distribution network projects, especially in areas with many trees, serious pollution, harsh environment and high population density. Its advantages are obvious. It not only shortens the line-to-line distance and saves the line corridor, but also reduces the incidence of phase-to-phase short circuit and ground fault, and improves the safety and reliability of the line.

[0003] The main structure of the overhead insulated cable takes the conductor as the core, usually uses copper, aluminum or aluminum alloy materials with high electrical conductivity, and wraps the outer layer with weather-resistant polyvinyl chloride or weather-resistant polyethylene insulation. Some models also have a protective layer to enhance mechanical protection. Its working principle is to use the excellent electrical conductivity of the conductor to transmit electrical energy, and the outer insulation layer effectively isolates the conductor from the outside world to prevent electrical leakage, short circuit and other situations. At the same time, it adapts to the overhead environment with its structural characteristics, realizing safe and stable power transmission.

[0004] Some existing overhead insulated cables have a solid or simply composite core, which generally has the contradiction that the weight and strength are difficult to balance, and is prone to overall damage under accidental damage. At the same time, the smooth surface contact between the multiple layers of the cable is prone to relative slipping under torsional load, resulting in insufficient overall torsional stiffness and stress concentration risk. In addition, traditional cables lack active protection and repair capabilities, and external physical micro-damage will continue to expand, and strong sunlight will heat the cable core, limit the current-carrying capacity and accelerate material aging. Therefore, a weather-resistant high-strength tensile overhead insulated cable and a preparation method thereof are proposed. SUMMARY

[0005] In view of the shortcomings of the prior art, the present application provides a weather-resistant high-strength tensile overhead insulated cable and a preparation method thereof, which solves the problems of difficulty in balancing weight and strength and insufficient torsional stiffness.

[0006] To achieve the above object, the application is implemented by the following technical scheme: a weather-resistant high-strength tensile overhead insulated cable, comprising a cable conductor, the outer part of the cable conductor is provided with a protection mechanism, the inner part of the protection mechanism is provided with a supporting mechanism, the outer part of the protection mechanism is connected with an outer sheath through a shock absorption mechanism, the outer part of the cable conductor is fixedly connected with a load-bearing layer, the outer part of the load-bearing layer is provided with a repair layer, and the outer part of the repair layer is fixedly connected with a heat-insulating fireproof layer.

[0007] Preferably, the shock absorption mechanism comprises an elastic rubber layer, the inner side of the elastic rubber layer is fixedly connected to the outer part of the heat-insulating fireproof layer, and the inner part of the elastic rubber layer is fixedly connected with a plurality of spiral wings.

[0008] Preferably, the plurality of spiral wings are distributed in a spiral array in the inner part of the elastic rubber layer, and the shape of the spiral wings is wing-shaped.

[0009] Preferably, the supporting mechanism comprises an outer wall, the outer part of the outer wall is arranged in the inner part of the load-bearing layer, the inner side of the outer wall is fixedly connected with a plurality of diaphragms, the proximal side of the plurality of diaphragms is fixedly connected with an inner wall, and the outer part of the outer wall is fixedly connected with a plurality of protrusions.

[0010] Preferably, the plurality of diaphragms are distributed in a circumferential array on the proximal side of the outer wall and the inner wall, and the proximal side of two diaphragms is in a cavity structure.

[0011] Preferably, the inner part of the repair layer is provided with a plurality of sliding grooves, and the outer part of the protrusion is slidingly connected in the inner part of the sliding groove.

[0012] Preferably, the outer part of the elastic rubber layer is fixedly connected to the inner side of the outer sheath, and the outer part of the elastic rubber layer is fixedly connected to the inner side of the outer sheath.

[0013] A preparation method of a weather-resistant high-strength tensile overhead insulated cable, On the outer part of the cable conductor, a hollow and integrally formed tubular load-bearing layer with internal diaphragms and external longitudinal protrusions is prepared by using a three-dimensional weaving process and using carbon fiber or aramid fiber composite materials; On the outer surface of the load-bearing layer, a repair layer composed of a thermoplastic elastomer containing self-repairing microcapsules is coated by a melt extrusion process, which fills the repair layer material into the grooves between the protrusions, thereby forming a mechanical interlocking structure.

[0014] On the outer surface of the repair layer, a heat-insulating fireproof layer composed of aerogel composite ceramic fiber material is coated; On the outer surface of the heat-insulating fireproof layer, a damping structure composed of an elastic rubber layer and a plurality of spiral wings fixed on the layer is arranged; An outer sheath is prepared by an extrusion process outside the damping structure; Finally, the outer surface of the outer sheath is subjected to laser micro-texturing treatment to form a bionic surface with super-hydrophobic and self-cleaning functions.

[0015] Preferably, the step of coating the repair layer is specifically to control the pressure and temperature of the extrusion die, so that the molten thermoplastic elastomer material is accurately and gaplessly filled into the grooves on the surface of the load-bearing layer, and after cooling and solidification, the protruding blocks formed on the inner wall of the repair layer are fully shape-fitted and locked with the grooves of the load-bearing layer.

[0016] Preferably, the step of setting the damping structure and the outer sheath specifically includes first laying the elastic rubber layer on the heat-insulating fireproof layer; Then a plurality of preformed spiral fin strips are arranged and fixed on the elastic rubber layer according to the preset pitch and rotation direction; Finally, through an outer layer extrusion process, the material of the outer sheath is integrally coated outside the spiral fin strips and the elastic rubber layer to form a composite outer layer with integrated structure and function.

[0017] The application provides a weather-resistant high-strength tensile overhead insulated cable and a preparation method thereof. 1、The application realizes the high optimization of structure and multiple protection through the precise cooperation of the internal functional layers. The core tubular load-bearing layer has a hollow bionic structure containing a diaphragm inside, which greatly reduces the self-weight while providing excellent bending and torsional stiffness; when the load-bearing layer is subjected to accidental impact, the internal diaphragm effectively prevents the longitudinal spread of micro-cracks like a firewall, limiting the damage to a local area. More importantly, the longitudinal protrusions on the outer wall of the load-bearing layer and the inner wall grooves of the repair layer form a toothed mechanical interlocking, which firmly locks the inner and outer layers when the cable is subjected to torsional load, so that they resist torsion as a single whole and eliminate interlayer slip. At the same time, the repair layer absorbs external impact in an instant, and if micro-cracks occur, the microcapsules inside will immediately rupture and release the repair agent to actively heal the wound and prevent damage from being transmitted inward. The outermost heat-insulating fireproof layer can continuously reflect external heat radiation to provide a mild working environment for the internal structure, thereby improving the load capacity and delaying material aging.

[0018] 2. This invention uses surface laser microtexturing to create a biomimetic superhydrophobic surface. When rain, snow, or fog contacts the sheath, this microstructure prevents water droplets from spreading and infiltrating, causing them to form rolling spheres. This process has a dual effect: first, in the severe cold conditions of winter, the difficult-to-attach liquid water fundamentally prevents the formation of severe ice, greatly reducing the pressure of ice and snow loads on the entire line; second, in everyday environments, the rolling water droplets act like miniature cleaning balls, easily removing dust and contaminants from the surface, achieving self-cleaning of the cable. This design, combined with the corrosion and UV resistance of the sheath material itself, provides the cable with maintenance-free, long-lasting ultimate external protection.

[0019] 3. The present invention is composed of an elastic rubber layer and multiple spiral wing strips embedded therein. When wind flows through the cable, the special airfoil cross-section of the spiral wing strips will actively destroy the formation of regular vortices, thereby suppressing the generation of vibrations from an aerodynamic perspective. When vibrations do occur, a tiny relative movement will occur between the larger cable body and the lighter spiral wing strips. This movement will continuously stretch and shear the elastic rubber layer between the two, and through internal friction, the harmful vibration mechanical energy will be efficiently converted into harmless heat energy and dissipated. This dual aerodynamic and mechanical vibration reduction process continues along the entire length of the cable, providing dynamic and stable protection without dead angles. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A perspective view of the present invention; Figure 2 Schematic diagram of the structure of the elastic rubber layer of the present invention; Figure 3 Schematic diagram of the structure of the load-bearing layer of the present invention; Figure 4 Schematic diagram of the structure of the elastic rubber layer of the present invention; Figure 5 for Figure 4 Enlarged view of point A in the middle; Figure 6 Schematic diagram of the structure of the outer wall layer of the present invention.

[0021] Among them, 1. Outer sheath; 2. Shock-absorbing mechanism; 21. Elastic rubber layer; 22. Spiral wing strip; 3. Protection mechanism; 31. Heat insulation and fireproof layer; 32. Repair layer; 33. Load-bearing layer; 4. Support mechanism; 41. Outer wall layer; 42. Diaphragm; 43. Inner wall layer; 44. Protrusion; 5. Cable conductor. DETAILED DESCRIPTION

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the present specification. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] Example 1: Please see the attached Figure 1 To the attached Figure 3 The embodiment of the present invention provides a weather-resistant high-strength tensile-resistant overhead insulated cable, including a cable conductor 5. The cable conductor 5 is the core part of the cable for transmitting power, and its material and structure directly affect the conductive performance of the cable. A protective mechanism 3 is provided on the outside of the cable conductor 5, which provides multiple protections for the cable conductor 5 to resist erosion and physical damage from the external environment. A supporting mechanism 4 is provided inside the protective mechanism 3, which enhances the structural strength of the cable and improves its mechanical properties such as anti-bending and anti-torsion. The outside of the protective mechanism 3 is connected to the outer sheath 1 through a shock-absorbing mechanism 2. The shock-absorbing mechanism 2 can reduce the vibration and impact of the cable. The outer sheath 1 serves as the outermost barrier of the cable and provides comprehensive protection. The outside of the cable conductor 5 is fixedly connected to a load-bearing layer 33, which bears the main tension of the cable to ensure that the cable maintains structural stability in an overhead environment. A repair layer 32 is provided on the outside of the load-bearing layer 33, which can repair microcracks generated on itself and extend the service life of the cable. The outside of the repair layer 32 is fixedly connected to a heat-insulating and fire-proof layer 31, which effectively blocks heat transfer and protects the internal structure from high temperature. Please see the attached Figure 1 , Attachment Figure 4 and attached Figure 5 The shock absorbing mechanism 2 includes an elastic rubber layer 21. The inner side of the elastic rubber layer 21 is fixedly connected to the outside of the heat-insulating and fire-proof layer 31. The elastic rubber layer 21 has good elasticity and toughness, can absorb external vibrations and impacts, and plays a buffering role. A plurality of spiral wing strips 22 are fixedly connected to the inside of the elastic rubber layer 21. The plurality of spiral wing strips 22 are distributed in a spiral array inside the elastic rubber layer 21. The spiral structure of the spiral wing strips 22 can destroy air vortices and reduce vortex-induced vibrations. At the same time, energy is consumed through relative motion when vibration occurs. The shape of the spiral wing strips 22 is wing-shaped, which helps to optimize aerodynamic performance and further reduce the impact of vibration. The outside of the elastic rubber layer 21 is fixedly connected to the inner side of the outer sheath 1, so that the shock absorbing mechanism 2 is tightly combined with the outer sheath 1 to form a unified protection system. Please see the attached Figure 1 , Attachment Figure 3 and attached Figure 6The support mechanism 4 includes an outer wall layer 41. The outer portion of the outer wall layer 41 is arranged inside the bearing layer 33. The outer wall layer 41 provides an external frame for the support mechanism 4 to enhance the overall structural strength. The inner side of the outer wall layer 41 is fixedly connected to a plurality of diaphragms 42. The adjacent side of the plurality of diaphragms 42 is fixedly connected to an inner wall layer 43. The diaphragms 42 and the inner wall layer 43 together form a structure similar to a "bamboo node", which can effectively prevent the expansion of cracks and improve the damage tolerance of the cable. The outer wall layer 41 is fixedly connected to a plurality of protrusions 4 4. Multiple diaphragms 42 are distributed in a circular array on the adjacent side of the outer wall layer 41 and the inner wall layer 43. This distribution method makes the supporting force evenly distributed and enhances the structural stability. The adjacent side of the two diaphragms 42 forms a cavity structure, which can be used as an air convection heat dissipation channel to help the cable dissipate heat. The interior of the repair layer 32 is provided with multiple sliding grooves, and the outer part of the protrusion 44 is slidably connected to the inner part of the sliding groove. This toothed structure can prevent the inner and outer layers from rotating and slipping relative to each other, improve the torsional rigidity, and ensure uniform stress transmission. Example 2: The embodiment discloses a preparation method of a weather-resistant high-strength tensile overhead insulated cable, and the preparation method comprises the following steps: adopting a three-dimensional weaving process to prepare a tubular load-bearing layer 33 with a hollow structure, an internal diaphragm 42 and an external longitudinal protrusion 44 on the outside of a cable conductor 5, using carbon fiber or aramid fiber composite material, which can ensure that the load-bearing layer 33 is structurally stable, the components are tightly connected, and the tensile performance is improved; coating a repair layer 32 composed of a thermoplastic elastomer containing self-repairing microcapsules on the outer surface of the load-bearing layer 33 by a melting extrusion process, which can make the material of the repair layer 32 fill into the grooves between the protrusions 44, so as to form a mechanical interlocking structure, enhance the bonding force between the load-bearing layer 33 and the repair layer 32, and ensure effective stress transmission; coating a heat-insulating fireproof layer 31 composed of aerogel composite ceramic fiber material on the outer surface of the repair layer 32, which can fully exert the heat-insulating and fireproof performance and provide effective protection for the internal structure; and arranging a damping structure composed of an elastic rubber layer 21 and a plurality of spiral fin strips 22 fixed on the elastic rubber layer 21 on the outer surface of the heat-insulating fireproof layer 31, which can effectively reduce the influence of vibration on the cable. An outer sheath 1 is prepared on the outside of the damping structure by an extrusion molding process, and finally, laser micro-texturing treatment is performed on the outer surface of the outer sheath 1 to form a biomimetic surface with super-hydrophobic and self-cleaning functions, so as to improve the weather resistance and self-cleaning ability of the outer sheath 1. By controlling the pressure and temperature of the extrusion die, the molten thermoplastic elastomer material is accurately and gaplessly filled into the grooves on the surface of the load-bearing layer 33, and after cooling and solidification, the protruding blocks formed on the inner wall of the repair layer 32 are completely shape-fitted and locked with the grooves of the load-bearing layer 33, further strengthening the mechanical interlocking effect. The steps of arranging the damping structure and the outer sheath 1 specifically comprise the following steps: first, laying the elastic rubber layer 21 on the heat-insulating fireproof layer 31, then arranging and fixing a plurality of preformed spiral fin strips 22 on the elastic rubber layer 21 according to the preset pitch and rotation direction, and finally integrally coating the material of the outer sheath 1 outside the spiral fin strips 22 and the elastic rubber layer 21 by an outer layer extrusion process to form a composite outer layer with integrated structure and function, so as to ensure that the layers are tightly combined and play a synergistic role.

[0024] Working Principle: During use, the cable conductor 5 is wrapped with a load-bearing layer 33, a hollow tubular structure containing multiple diaphragms 42. The load-bearing layer 33 is made of a three-dimensionally woven carbon fiber or aramid fiber composite material, while the diaphragms 42 are integrally formed during the weaving process. The hollow tube offers far superior bending and torsional resistance to a solid rod of the same weight. This structure reduces the weight of the load-bearing core while providing the same level of, or even higher, tensile strength. This further reduces the cable's deadweight, enabling longer spans or lowering tower requirements. The internal "bamboo-jointed" diaphragms 42 act as crack blockers. Even if a certain section of the core is subjected to an unexpected impact and produces microcracks, the diaphragm 42 can effectively prevent the cracks from extending longitudinally along the entire cable, limiting the damage to a very small range, greatly improving the damage tolerance and safety of the cable. The hollow channel can serve as a passive air convection heat dissipation duct. At the same time, the protrusion 44 will be inside the slide groove inside the repair layer 32 to achieve a toothing effect. When the cable is subjected to a torsional load, this toothing structure can firmly lock the inner and outer layers together to prevent relative rotation and slippage between them, which makes the entire cable behave like a whole, greatly improving its torsional stiffness. The interlocking structure ensures that under any load, stress can be efficiently and evenly transferred between the layers, avoiding stress concentration on a single smooth interface, thereby improving the overall structural reliability and durability of the cable.

[0025] The repair layer 32 is made of a thermoplastic elastomer containing self-repairing microcapsules. The TPE material is soft and elastic, and can absorb external physical shocks and vibrations, thus playing a buffering role. More importantly, when microcracks occur, the microcapsules will rupture and release repair agents to "heal" the cracks and prevent them from extending to the inner layer. The thermal insulation and fireproof layer 31 is made of a flexible felt or coating made of aerogel composite ceramic fiber. The white surface can reflect most of the sunlight radiation, and aerogel is the solid with the lowest known thermal conductivity. This combination can effectively block the external heat from transferring inward, and can significantly reduce the operating temperature of the cable conductor 5 in the hot summer, thereby increasing the current carrying capacity and slowing down the aging of the polymer materials of the load-bearing layer 33 and the repair layer 32. The outer sheath 1 is made of a fluorinated polymer or modified HDPE with a surface treated with laser microtexturing. This treatment forms microscopic grooves and protrusions on the surface of the sheath similar to shark skin or lotus leaves. This bionic surface has superhydrophobic and low adhesion properties, which can effectively resist the adhesion of rain, snow and ice, fundamentally reducing the ice and snow load, which directly reduces the burden on the load-bearing layer 33. At the same time, rainwater can easily wash away surface dirt, achieving self-cleaning. The fluorinated polymer itself is resistant to UV rays, acid and alkali corrosion, and high and low temperature resistance, providing ultimate protection for all internal layers.

[0026] The outer sheath 1 is connected to the heat-insulating and fire-proof layer 31 through an elastic rubber layer 21, and a plurality of spiral wing strips 22 are fixedly connected between the elastic rubber layers 21. The spiral shape of the spiral wing strips 22 can effectively destroy the regular eddies formed when air flows over the cable surface, and suppress the generation of vortex-induced vibrations from the aerodynamic level. When vibration does occur, a small relative movement will occur between the larger cable body and the lighter spiral wing strips 22. This movement will stretch and shear the viscoelastic material between them, and efficiently convert the vibration mechanical energy into heat energy and dissipate it. This built-in vibration absorber is distributed along the entire length of the cable, providing vibration protection without dead angles for the entire line, and is particularly suitable for areas with complex terrain and changeable wind conditions.

[0027] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A weather-resistant high-strength tensile-resistant overhead insulated cable, comprising a cable conductor (5), characterized in that: The cable conductor (5) is provided with a protective mechanism (3) on the outside, a supporting mechanism (4) is provided on the inside of the protective mechanism (3), the protective mechanism (3) is connected to an outer sheath (1) on the outside via a shock-absorbing mechanism (2), the cable conductor (5) is fixedly connected to a load-bearing layer (33) on the outside, a repair layer (32) is provided on the outside of the load-bearing layer (33), and the repair layer (32) is fixedly connected to a heat-insulating and fire-proof layer (31) on the outside.

2. A weather-resistant high-strength tensile overhead insulated cable according to claim 1, characterized in that: The shock absorbing mechanism (2) comprises an elastic rubber layer (21), the inner side of the elastic rubber layer (21) is fixedly connected to the outside of the heat-insulating and fire-proof layer (31), and a plurality of spiral wing strips (22) are fixedly connected to the inside of the elastic rubber layer (21).

3. The weather-resistant high-strength tensile overhead insulated cable according to claim 1, characterized in that: A plurality of spiral wing strips (22) are distributed in a spiral array inside the elastic rubber layer (21), and the spiral wing strips (22) are wing-shaped.

4. The weather-resistant high-strength tensile overhead insulated cable according to claim 1, characterized in that: The support mechanism (4) comprises an outer wall (41), the outer portion of the outer wall (41) is arranged inside the bearing layer (33), the inner side of the outer wall (41) is fixedly connected to a plurality of diaphragms (42), adjacent sides of the plurality of diaphragms (42) are fixedly connected to the inner wall (43), and the outer portion of the outer wall (41) is fixedly connected to a plurality of protrusions (44).

5. The weather-resistant high-strength tensile-resistant overhead insulated cable according to claim 4, characterized in that: The plurality of diaphragms (42) are distributed in a circumferential array on the adjacent side of the outer wall (41) and the inner wall (43), and the adjacent sides of the two diaphragms (42) form a cavity structure.

6. The weather-resistant high-strength tensile-resistant overhead insulated cable according to claim 4, characterized in that: A plurality of sliding grooves are provided inside the repair layer (32), and the outside of the protrusion (44) is slidably connected to the inside of the sliding grooves.

7. The weather-resistant high-strength tensile-resistant overhead insulated cable according to claim 2, characterized in that: The outside of the elastic rubber layer (21) is fixedly connected to the inside of the outer sheath (1), and the outside of the elastic rubber layer (21) is fixedly connected to the inside of the outer sheath (1).

8. The method for preparing a weather-resistant high-strength tensile-resistant overhead insulated cable according to claims 1-7, characterized in that: On the outside of the cable conductor (5), a hollow tubular bearing layer (33) integrally formed with an internal diaphragm (42) and an external longitudinal protrusion (44) is prepared using a three-dimensional weaving process and carbon fiber or aramid fiber composite material; A repair layer (32) composed of a thermoplastic elastomer containing self-repairing microcapsules is coated on the outer surface of the bearing layer (33) by a melt extrusion process, wherein the repair layer (32) material is filled into the grooves between the protrusions (44), thereby forming a mechanical interlocking structure; A heat-insulating and fire-proofing layer (31) composed of an aerogel composite ceramic fiber material is coated on the outer surface of the repair layer (32); On the outer surface of the heat-insulating and fire-proofing layer (31), a vibration-damping structure consisting of an elastic rubber layer (21) and a plurality of spiral wing strips (22) fixed on the layer is provided; On the outer side of the vibration damping structure, an outer sheath (1) is prepared by an extrusion molding process; Finally, the outer surface of the outer sheath (1) is subjected to laser microtexturing treatment to form a bionic surface with super-hydrophobic and self-cleaning functions.

9. The preparation method according to claim 8, characterized in that The step of coating the repair layer (32) is specifically to control the pressure and temperature of the extrusion die so that the molten thermoplastic elastomer material is accurately and gaplessly filled into the groove on the surface of the bearing layer (33), and after cooling and solidification, the protrusions formed on the inner wall of the repair layer (32) are completely locked in shape with the groove of the bearing layer (33).

10. The preparation method according to claim 8, characterized in that The steps of providing the vibration damping structure and the outer sheath (1) specifically include: firstly, laying the elastic rubber layer (21) on the heat insulation and fireproof layer (31); Then, a plurality of prefabricated spiral wing strips (22) are arranged according to a preset pitch and direction of rotation and fixed on the elastic rubber layer (21); Finally, through the outer layer extrusion process, the material of the outer sheath (1) is integrally covered outside the spiral wing strip (22) and the elastic rubber layer (21), forming a composite outer layer with integrated structure and function.

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