Damage-resistant self-repairing heat-insulating flexible composite pipe for oil gathering and transportation and manufacturing method thereof

Abstract

The invention belongs to the technical field of petroleum composite pipes, and particularly relates to an anti-damage self-repairing heat-preservation flexible composite pipe for oil gathering and transportation and a manufacturing method of the anti-damage self-repairing heat-preservation flexible composite pipe. An anti-damage self-repairing heat-preservation flexible composite pipe for oil gathering and transportation comprises a lining layer, a reinforcing layer, a self-repairing heat-preservation anti-impact layer, an outer protection layer, a functional layer and an anti-damage outer protection sleeve which are sequentially connected from inside to outside, the self-repairing heat-preservation anti-impact layer comprises a polyurethane foam layer, and a polyethylene film is arranged on the side, close to the outer protection layer, of the polyurethane foam layer. A plurality of heating cables are arranged between the surface of the polyurethane foam layer and the polyethylene film, and a plurality of optical fibers and a camera are arranged in the functional layer. By arranging the self-repairing heat-preservation impact-resistant layer, the functional layer and the damage-resistant outer protective sleeve in the flexible composite pipe, the flexible composite pipe has good external force damage resistance during ground water injection, oil-water gathering and transportation and oil-water mixed transportation installation and laying, visual and effective detection can be achieved, the service safety performance can be improved, and meanwhile the heat preservation function and effective detection of the pipeline can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of oil composite pipes, and particularly relates to a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation and a manufacturing method thereof. Background Art

[0002] With the mass production of flexible composite pipes in the fields of water injection and methanol injection, due to their advantages such as corrosion resistance, low friction resistance, quick installation, and convenient transportation, they have attracted the attention of oilfields. The oilfield operation areas are widely distributed, with complex mountain terrains. It is difficult to carry out construction operations on the pipes coiled into whole rolls. There is a lack of professional construction equipment and standardized construction operation processes in the operation areas. During the installation and laying of flexible composite pipes, such as dragging, trench excavation, and pipe hoisting, the outer protective layer is often damaged. The damaged parts cannot be quickly and effectively detected. After backfilling, the damaged parts of the outer protective layer often become weak points in the pipeline operation. After 3 - 4 years of operation, large-area rupture and failure occur, bringing great risks to the safe service of the pipeline and the environment.

[0003] At present, during the construction process of existing flexible composite pipe materials in the operation areas, due to operations such as trenching and dragging in mountainous areas, and the use of operation tools such as cranes, forklifts, hoes, etc., the outer protective layer is damaged and cracked. On-site, only visual inspection can be used to observe the degree of damage to the outer protective layer. Limited by on-site operation environments, pipe section repair tools, fittings, etc., it is relatively difficult to repair the frequently damaged outer protective layer pipes on-site. Therefore, for pipes with visually and intuitively judged not serious damage to the outer protective layer, after passing the short-term pressure test, pipe section laying and backfilling are carried out, which often poses potential safety hazards for later safe operation. Summary of the Invention

[0004] Aiming at the above problems, the purpose of the present invention is to provide a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation and a manufacturing method thereof. By setting a self-repairing heat-insulating impact-resistant layer, a functional layer, and an anti-damage outer protective sleeve in the flexible composite pipe, it has better anti-external force damage ability during ground water injection, oil-water gathering and transportation, and oil-water mixed transportation installation and laying, and can achieve intuitive and effective detection, greatly improving the service safety performance of the flexible composite pipe. At the same time, the heat-insulating function of the pipeline and effective detection can be realized.

[0005] The technical solution of the present invention lies in: A flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation, which includes, from the inside to the outside, a lining layer, a reinforcing layer, a self-repairing heat-insulating impact-resistant layer, an outer protective layer, a functional layer, and an anti-damage outer protective sleeve connected in sequence. The self-repairing heat-insulating impact-resistant layer includes a polyurethane foam layer. A polyethylene film is provided on one side of the polyurethane foam layer close to the outer protective layer. A plurality of heating cables are provided between the surface of the polyurethane foam layer and the polyethylene film. A plurality of optical fibers and a plurality of cameras are provided in the functional layer. The cameras are connected to the optical fibers.

[0006] The thickness of the inner lining layer is 3 mm to 6 mm, and the inner lining layer is made of one of polyethylene, polyvinylidene fluoride, polypropylene, polyvinyl chloride, polyamide, and polyetheretherketone by extrusion molding.

[0007] The thickness of the reinforcing layer is 2 to 3 mm, and the reinforcing layer is made of one of polyester fiber, ultra-high molecular weight polyethylene fiber, aramid fiber, glass fiber prepreg tape, and carbon fiber prepreg tape by winding, and the winding angle is 25 to 75°.

[0008] The thickness of the polyurethane foam layer is 3 to 5 mm, the thickness of the polyethylene film is 0.5 to 1 mm, and the number of heating cables is 6 to 32, which are evenly distributed on the surface of the polyurethane foam layer.

[0009] The thickness of the outer protective layer is 4 mm to 4.5 mm. The outer protective layer includes an inner protective layer, a middle protective layer, and an outer protective layer from inside to outside. The thickness of the inner protective layer is 2 mm, the thickness of the middle protective layer is 1 mm, and the thickness of the outer protective layer is 1 to 1.5 mm. The inner protective layer, the middle protective layer, and the outer protective layer have different colors, which are red, yellow, and black in sequence.

[0010] The number of optical fibers is 8 to 16, and the optical fibers are evenly distributed on the outer surface of the outer protective layer.

[0011] The wall thickness of the anti-damage outer sheath is 1 to 2 mm. The anti-damage outer sheath is made by winding a metal strip on the outer surface of the functional layer, and the material of the metal strip is one of iron, aluminum, stainless steel, and copper.

[0012] A manufacturing method of a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation, which manufactures a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation as described above, includes the following steps: S1: Processing the inner lining layer. According to the inner diameter of the flexible composite pipe to be manufactured, one of polyethylene, polyvinylidene fluoride, polypropylene, polyvinyl chloride, and polyamide is made into the inner lining layer by extrusion molding. The extrusion molding parameters are: extrusion temperature 180 to 250 °C, melt pressure 10 to 80 MPa, and extrusion current 20 to 80 A; S2: Winding the reinforcing layer on the inner lining layer. It is made by winding one of polyester fiber, ultra-high molecular weight polyethylene fiber, aramid fiber, glass fiber prepreg tape, and carbon fiber prepreg tape on the outer side of the inner lining layer, and the winding angle is 25 to 75°; S3: Setting a self-repairing heat-insulating and impact-resistant layer outside the reinforcing layer. Specifically, a polyurethane foam layer is set on the reinforcing layer. The polyurethane foam layer forms a nano-porous structure by rapid cooling of supercritical fluid. A heating cable and a polyethylene film are set outside the polyurethane foam layer; S4: An outer protective layer is provided outside the self-healing heat-insulating and impact-resistant layer. The outer protective layer is divided into three layers, which are, from the inside out, a red inner protective layer, a yellow middle protective layer, and a black outer protective layer, with thicknesses of 2 mm, 1 mm, and 1 - 1.5 mm respectively. The outer protective layer is formed by co-extrusion of high-density polyethylene with red color powder, yellow color powder, and carbon black. The ratio of high-density polyethylene to color powder is 95:5 respectively, and different colors are distinguished through multi-layer co-extrusion. S5: A functional layer is provided outside the outer protective layer. An optical fiber is provided outside the outer protective layer. A tiny camera is connected to the optical fiber, and an IP address is set for the camera to observe the appearance of the outer protective layer. S6: An anti-damage outer protective sleeve is provided outside the functional layer. A metal thin strip is spirally wound on the outer surface of the outer protective layer to complete the manufacture of the flexible composite pipe.

[0013] In step S2, the reinforcing layer is one of polyester fiber, ultra-high molecular weight polyethylene fiber, and aramid fiber, and is wound and strengthened through a non-bonding structure. The fiber filaments of polyester fiber, ultra-high molecular weight polyethylene fiber, or aramid fiber are at least 2 even layers with opposite winding directions. The winding tension of each layer is 3 - 50 N, the winding angle is 25 - 75°, and the winding tension decreases by 5% from the inside to the outside.

[0014] In step S2, when the reinforcing layer is one of glass fiber pre-impregnated tape and carbon fiber pre-impregnated tape, the glass fiber pre-impregnated tape or carbon fiber pre-impregnated tape is prepared by resin compression molding. The weight ratio of resin to glass fiber or carbon fiber is 1:3. The resin is heated to a viscous flow state at 180 - 250 °C, the fiber bundle is traction-compressed into a tape, and then cooled and formed through a refrigeration tunnel. The fiber filaments of the glass fiber pre-impregnated tape or carbon fiber pre-impregnated tape are at least 2 even layers with opposite winding directions. The winding tension of each layer is 3 - 50 N, the winding angle is 25 - 75°, and the winding tension decreases by 5% from the inside to the outside. The glass fiber pre-impregnated tape or carbon fiber pre-impregnated tape is preheated before and after winding through tunnel heating, and the preheating temperature is 250 °C - 300 °C.

[0015] The technical effects of the present invention are as follows: 1. A self-healing heat-insulating and impact-resistant layer is provided between the reinforcing layer and the outer protective layer of the present invention. There is a polyurethane foam layer inside, which realizes the heat-insulating function during the process of transporting the medium. At the same time, the polyurethane foam layer can be heated through a cable to self-repair the cracks generated by damage, achieving self-healing; 2. The outer protective layer of the present invention is divided into three layers and can be distinguished by multiple different colors, so as to judge whether the flexible composite pipe can operate normally; 3. By arranging optical fibers on the outside of the outer protective layer of the present invention, and connecting a tiny camera to the optical fibers, the appearance of the outer protective layer can be observed through the camera, realizing the implementation monitoring of the outer protective layer; 4. By setting a metal thin strip as the outer protective sleeve, on the one hand, it can effectively avoid cracks and damages generated during on-site operations due to the low hardness of the outer protective layer. At the same time, when using a hoe, a shovel, or a crane to dig a trench, the sound generated by metal collision can play an effective reminder role, and the damage to the outer protective layer can be effectively reduced.

[0016] The following will be further described in conjunction with the accompanying drawings. Brief Description of the Drawings

[0017] Figure 1 It is a schematic structural diagram of a flexible composite pipe for anti-damage self-healing heat-insulating oil gathering and transportation according to an embodiment of the present invention.

[0018] Figure 2 It is a schematic structural diagram of the self-healing heat-insulating and impact-resistant layer according to an embodiment of the present invention.

[0019] Figure 3 It is a schematic structural diagram of the outer protective layer according to an embodiment of the present invention.

[0020] Figure 4 It is a schematic diagram of the monitoring process of the functional layer according to an embodiment of the present invention Reference numerals: 1 - inner lining layer, 2 - reinforcing layer, 3 - self-healing heat-insulating and impact-resistant layer, 4 - outer protective layer, 5 - functional layer, 6 - anti-damage outer protective sleeve, 31 - polyurethane foam layer, 32 - heating cable, 33 - polyethylene film, 41 - inner layer protective layer, 42 - middle layer protective layer, 43 - outer layer protective layer, 50 - detection point, 51 - camera, 52 - optical fiber, 53 - remote video server, 54 - remote optical fiber switch, 55 - memory, 56 - transmission cable, 57 - monitoring terminal. Detailed Embodiments Embodiment 1

[0021] As Figures 1 to 4As shown in the figure, a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation includes, from the inside to the outside, a lining layer 1, a reinforcing layer 2, a self-repairing heat-insulating and anti-impact layer 3, an outer protective layer 4, a functional layer 5, and an anti-damage outer protective sleeve 6 that are connected in sequence. The self-repairing heat-insulating and anti-impact layer 3 includes a polyurethane foam layer 31. A polyethylene film 33 is provided on one side of the polyurethane foam layer 31 close to the outer protective layer 4. A plurality of heating cables 32 are provided between the surface of the polyurethane foam layer 31 and the polyethylene film 33. A plurality of optical fibers 51 and a plurality of cameras 52 are provided in the functional layer 5. The cameras 52 are connected to the optical fibers 51.

[0022] During actual use, 53-, 54-remote optical fiber switch, 55-storage, 56-wire, 57-monitoring terminal.

[0023] The self-repairing heat-insulating and anti-impact layer 3 of the present invention includes a polyurethane foam layer 31, which has a heat-insulating function. Heating cables 32 are arranged outside the polyurethane foam layer 31. By heating the polyurethane foam layer, the temperature is controlled at 50~80°C to self-repair the cracks generated by damage. A plurality of optical fibers 51 and a plurality of cameras 52 are provided in the functional layer 5. The cameras 52 are connected to the optical fibers 51. The cameras 52 can realize visual inspection of the video at the detection point 50 and transmit it to the remote video server 53 through the optical fibers 51, and are respectively stored in the memory 55 through the remote optical fiber switch 54 and transmitted to the monitoring terminal 57 through the transmission cable 56. By arranging a self-repairing heat-insulating and anti-impact layer, a functional layer, and an anti-damage outer protective sleeve in the flexible composite pipe, the present invention has good anti-external force damage ability during ground water injection, oil-water gathering and transportation, and oil-water mixed transportation installation and laying, and can realize intuitive and effective detection, greatly improving the service safety performance of the flexible composite pipe. At the same time, the heat-insulating function of the pipeline and effective detection can be realized. Example 2

[0024] Preferably, on the basis of Example 1, in this embodiment, the thickness of the lining layer 1 is 3mm~6mm, and the lining layer 1 is made of one of polyethylene, polyvinylidene fluoride, polypropylene, polyvinyl chloride, polyamide, and polyether ether ketone by extrusion molding.

[0025] During actual use, the lining layer 1 of the present invention is made of one of polyethylene, polyvinylidene fluoride, polypropylene, polyvinyl chloride, polyamide, and polyether ether ketone by extrusion molding, and the lining layer 1 is used to transport the medium. Example 3

[0026] Preferably, on the basis of Example 1 or Example 2, in this embodiment, the thickness of the reinforcing layer 2 is 2~3mm, and the reinforcing layer 2 is made of one of polyester fiber, ultra-high molecular weight polyethylene fiber, aramid fiber, glass fiber prepreg, and carbon fiber prepreg by winding, and the winding angle is 25~75°.

[0027] In actual use, the reinforcing layer 2 of the present invention is made by winding with one of polyester fiber, ultra-high molecular weight polyethylene fiber, aramid fiber, glass fiber prepreg tape, and carbon fiber prepreg tape. The winding angle is 25-75°, and the reinforcing layer 2 provides the main pressure-bearing mode of the pipeline, achieving a strength of 10-90 MPa for pressure-bearing. Example 4

[0028] Preferably, on the basis of Example 1 or Example 3, in this embodiment, the thickness of the polyurethane foam layer 31 is 3-5 mm, the thickness of the polyethylene film 33 is 0.5-1 mm, and the number of the heating cables 32 is 16-32, which are evenly distributed on the surface of the polyurethane foam layer 31.

[0029] In actual use, the thickness of the polyurethane foam layer 31 of the present invention is 3-5 mm, the thickness of the polyethylene film 33 is 0.5-1 mm, the number of the heating cables 32 is 16-32, which are evenly distributed on the surface of the polyurethane foam layer 31. The polyurethane foam layer 31 forms a nano-porous structure through rapid cooling by supercritical fluid to achieve the heat preservation function. A heating cable 32 is arranged outside the polyurethane foam layer 31, and by heating the polyurethane foam layer, the temperature is controlled at 50-80 °C to perform self-repair on the cracks generated by damage. Example 5

[0030] Preferably, on the basis of Example 1 or Example 4, in this embodiment, the thickness of the outer protective layer 4 is 4 mm-4.5 mm. The outer protective layer 4 includes an inner protective layer 41, a middle protective layer 42, and an outer protective layer 43 from inside to outside. The thickness of the inner protective layer 41 is 2 mm, the thickness of the middle protective layer 42 is 1 mm, and the thickness of the outer protective layer 43 is 1-1.5 mm. The inner protective layer 41, the middle protective layer 42, and the outer protective layer 43 have different colors, which are red, yellow, and black in sequence.

[0031] In actual use, the outer protective layer 4 of the present invention includes an inner protective layer 41, a middle protective layer 42, and an outer protective layer 43 from inside to outside. The differentiation of different colors of the outer protective layer 4 is realized through coextrusion of multiple layers, and it can be judged whether the flexible composite pipe can operate normally. Oilfield users can judge accordingly that when the damage of the outer protective layer shows black, the flexible composite pipe can still operate normally; when the damage of the outer protective layer shows yellow, the flexible composite pipe should be marked and replaced within 3-6 months; when the damage of the outer protective layer shows red, it should be replaced within 1 month. Example 6

[0032] Preferably, on the basis of Embodiment 1 or Embodiment 5, in this embodiment, the number of the optical fibers 51 is 8 to 16, and the optical fibers 51 are evenly distributed on the outer surface of the outer protective layer 4.

[0033] During actual use, the number of the optical fibers 51 of the present invention is 8 to 16, and the optical fibers 51 are evenly distributed on the outer surface of the outer protective layer 4. Tiny cameras 52 are connected to the optical fibers 51, and IP addresses are set for the cameras 52. The appearance of the outer protective layer can be observed through the cameras 52 to realize the implementation monitoring of the outer protective layer. Embodiment 7

[0034] Preferably, on the basis of Embodiment 1 or Embodiment 6, in this embodiment, the wall thickness of the anti-damage outer sheath 6 is 1 to 2 mm. The anti-damage outer sheath 6 is made by winding a metal strip on the outer surface of the functional layer 5, and the material of the metal strip is one of iron, aluminum, stainless steel, and copper.

[0035] During actual use, the wall thickness of the anti-damage outer sheath 6 of the present invention is 1 to 2 mm. The anti-damage outer sheath 6 is made by winding a metal strip on the outer surface of the functional layer 5, and the material of the metal strip is one of iron, aluminum, stainless steel, and copper. By setting the metal strip as the outer protective sleeve, on the one hand, cracks and damages caused by the low hardness of the outer protective layer during on-site operations can be limitedly avoided. At the same time, when using a hoe, a shovel, or a crane to dig a trench, the sound generated by metal collision can play an effective reminder role, and the damage to the outer protective layer can be effectively reduced. Embodiment 8

[0036] A manufacturing method of a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation, for manufacturing a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation as described above, includes the following steps: S1: Processing the inner liner layer 1. According to the inner diameter size of the flexible composite pipe to be manufactured, one of polyethylene, polyvinylidene fluoride, polypropylene, polyvinyl chloride, and polyamide is made into the inner liner layer 1 by extrusion molding. The extrusion molding parameters are: extrusion temperature 180 to 250 °C, melt pressure 10 to 80 MPa, and extrusion current 20 to 80 A; S2: Winding the reinforcing layer 2 on the inner liner layer 1, which is made by winding one of polyester fiber, ultra-high molecular weight polyethylene fiber, aramid fiber, fiberglass prepreg tape, and carbon fiber prepreg tape on the outer side of the inner liner layer 1, and the winding angle is 25 to 75 °; S3: Setting the self-repairing heat-insulating and impact-resistant layer 3 outside the reinforcing layer 2. Specifically, a polyurethane foam layer is set on the reinforcing layer 2. The polyurethane foam layer forms a nano-porous structure through rapid cooling of supercritical fluid. A heating cable 32 and a polyethylene film 33 are set outside the polyurethane foam layer; S4: An outer protective layer 4 is arranged outside the self-healing heat-insulating and impact-resistant layer 3. The outer protective layer 4 is divided into three layers, which are, from the inside out, a red inner protective layer 41, a yellow middle protective layer 42, and a black outer protective layer 43, with thicknesses of 2 mm, 1 mm, and 1 - 1.5 mm respectively. The outer protective layer 4 is formed by co-extrusion of high-density polyethylene with red color powder, yellow color powder, and carbon black. The ratio of high-density polyethylene to color powder is 95:5 respectively, and different colors are distinguished through multi-layer co-extrusion. S5: A functional layer 5 is arranged outside the outer protective layer 4. An optical fiber 51 is arranged on the outside of the outer protective layer 4. A tiny camera 52 is connected to the optical fiber 51, and an IP address is set for the camera 52 to observe the appearance of the outer protective layer. S6: An anti-damage outer protective sleeve 6 is arranged outside the functional layer 5. A metal thin strip is spirally wound on the outer surface of the outer protective layer to complete the manufacture of the flexible composite pipe.

[0037] In the step S2, the reinforcing layer 2 is one of polyester fiber, ultra-high molecular weight polyethylene fiber, and aramid fiber, and is wound and strengthened through a non-bonding structure. The fiber filaments of polyester fiber, ultra-high molecular weight polyethylene fiber, or aramid fiber are at least 2 even layers with opposite winding directions. The winding tension of each layer is 3 - 50 N, the winding angle is 25 - 75°, and the winding tension decreases by 5% from the inside outwards.

[0038] In the step S2, when the reinforcing layer 2 is one of glass fiber prepreg tape and carbon fiber prepreg tape, the glass fiber prepreg tape or carbon fiber prepreg tape is prepared by resin compression molding. The weight ratio of resin to glass fiber or carbon fiber is 1:3. The resin is heated to a viscous flow state at 180 - 250 °C, the fiber bundle is traction-compressed into a tape, and then cooled and formed through a refrigeration tunnel. The fiber filaments of the glass fiber prepreg tape or carbon fiber prepreg tape are at least 2 even layers with opposite winding directions. The winding tension of each layer is 3 - 50 N, the winding angle is 25 - 75°, and the winding tension decreases by 5% from the inside outwards. The glass fiber prepreg tape or carbon fiber prepreg tape is preheated before and after winding through tunnel heating, and the preheating temperature is 250 °C - 300 °C.

[0039] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A flexible composite pipe for anti-damage self-repairing heat-insulated oil gathering and transportation, Characterized in that: It includes, from the inside to the outside, a lining layer (1), a reinforcing layer (2), a self-repairing heat-insulated anti-impact layer (3), an outer protective layer (4), a functional layer (5) and an anti-damage outer protective sleeve (6) that are connected in sequence. The self-repairing heat-insulated anti-impact layer (3) includes a polyurethane foam layer (31). A polyethylene film (33) is provided on one side of the polyurethane foam layer (31) close to the outer protective layer (4). A plurality of heating cables (32) are provided between the surface of the polyurethane foam layer (31) and the polyethylene film (33). A plurality of optical fibers (51) and a plurality of cameras (52) are provided in the functional layer (5). The cameras (52) are connected to the optical fibers (51).

2. The flexible composite pipe for anti-damage self-repairing heat-insulated oil gathering and transportation according to claim 1, Characterized in that: The thickness of the lining layer (1) is 3 mm to 6 mm, and the lining layer (1) is made by extrusion molding from one of polyethylene, polyvinylidene fluoride, polypropylene, polyvinyl chloride, polyamide, and polyether ether ketone.

3. The flexible composite pipe for anti-damage self-repairing heat-insulated oil gathering and transportation according to claim 1, Characterized in that: The thickness of the reinforcing layer (2) is 2 to 3 mm, and the reinforcing layer (2) is made by winding from one of polyester fiber, ultra-high molecular weight polyethylene fiber, aramid fiber, glass fiber prepreg, and carbon fiber prepreg, and the winding angle is 25 to 75°.

4. The flexible composite pipe for anti-damage self-repairing heat-insulated oil gathering and transportation according to claim 1, Characterized in that: The thickness of the polyurethane foam layer (31) is 3 to 5 mm, the thickness of the polyethylene film (33) is 0.5 to 1 mm, and the number of the heating cables (32) is 16 to 32, which are evenly distributed on the surface of the polyurethane foam layer (31).

5. The flexible composite pipe for anti-damage self-repairing heat-insulated oil gathering and transportation according to claim 1, Characterized in that: The thickness of the outer protective layer (4) is 4 mm to 4.5 mm. The outer protective layer (4) includes an inner protective layer (41), a middle protective layer (42) and an outer protective layer (43) from the inside to the outside. The thickness of the inner protective layer (41) is 2 mm, the thickness of the middle protective layer (42) is 1 mm, and the thickness of the outer protective layer (43) is 1 to 1.5 mm. The inner protective layer (41), the middle protective layer (42) and the outer protective layer (43) have different colors, which are red, yellow and black in sequence.

6. The flexible composite pipe for anti-damage self-repairing heat-insulated oil gathering and transportation according to claim 1, Characterized in that: The number of the optical fibers (51) is 8 to 16, and the optical fibers (51) are evenly distributed on the outer surface of the outer protective layer (4).

7. The flexible composite pipe for anti-damage self-repairing heat-insulated oil gathering and transportation according to claim 1, Characterized in that: The wall thickness of the anti-damage outer sleeve (6) is 1 to 2 mm, and the anti-damage outer sleeve (6) is made by winding a metal strip on the outer surface of the functional layer (5). The material of the metal strip is one of iron, aluminum, stainless steel, and copper.

8. A manufacturing method of a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation, manufacturing a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation as described in claim 1, Characterized in that: It includes the following steps: S1: Processing the inner lining layer (1), according to the inner diameter size of the flexible composite pipe to be manufactured, one of polyethylene, polyvinylidene fluoride, polypropylene, polyvinyl chloride, and polyamide is made into the inner lining layer (1) by extrusion molding. The extrusion molding parameters are: extrusion temperature 180~250°C, melt pressure 10~80 MPa, extrusion current 20~80 A; S2: Wrapping the reinforcing layer (2) on the inner lining layer (1), which is made by winding one of polyester fiber, ultra-high molecular weight polyethylene fiber, aramid fiber, glass fiber prepreg tape, and carbon fiber prepreg tape on the outer side of the inner lining layer (1), and the winding angle is 25~75°; S3: Setting the self-repairing heat-insulating and impact-resistant layer (3) outside the reinforcing layer (2). Specifically, a polyurethane foam layer is set on the reinforcing layer (2), and the polyurethane foam layer forms a nano-porous structure through rapid cooling by supercritical liquid. A heating cable (32) and a polyethylene film (33) are set outside the polyurethane foam layer; S4: Setting the outer protective layer (4) outside the self-repairing heat-insulating and impact-resistant layer (3). The outer protective layer (4) is divided into three layers, which are the red inner protective layer (41), the yellow middle protective layer (42), and the black outer protective layer (43) from the inside to the outside, with thicknesses of 2 mm, 1 mm, and 1~1.5 mm respectively. The outer protective layer (4) is formed by co-extrusion of high-density polyethylene with red color powder, yellow color powder, and carbon black respectively. The ratio of high-density polyethylene to color powder is 95:5, and different colors are distinguished through multi-layer co-extrusion; S5: Setting the functional layer (5) outside the outer protective layer (4). An optical fiber (51) is set outside the outer protective layer (4), a tiny camera (52) is connected to the optical fiber (51), and an IP address is set for the camera (52) to observe the appearance of the outer protective layer; S6: Setting the anti-damage outer protective sleeve (6) outside the functional layer (5), and setting the metal thin strip on the outer surface of the outer protective layer by spiral winding to complete the manufacture of the flexible composite pipe.

9. According to the manufacturing method of a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation as described in claim 1, Characterized in that: In the step S2, the reinforcing layer (2) is one of polyester fiber, ultra-high molecular weight polyethylene fiber, and aramid fiber, and is wound and strengthened through a non-bonding structure. The fiber filaments of polyester fiber, ultra-high molecular weight polyethylene fiber, or aramid fiber are at least 2 even layers with opposite winding directions. The winding tension of each layer is 3~50 N, the winding angle is 25~75°, and the winding tension decreases by 5% from the inside to the outside.

10. According to the manufacturing method of a flexible composite pipe for anti-damage self-repairing heat-insulating oil gathering and transportation as described in claim 1, Characterized in that: In the step S2, when the reinforcing layer (2) is one of a glass fiber prepreg tape and a carbon fiber prepreg tape, the glass fiber prepreg tape or the carbon fiber prepreg tape is prepared by resin compression molding. The weight ratio of the resin to the glass fiber or the carbon fiber is 1:

3. The resin is heated to a viscous flow state at 180 to 250 °C, the fiber bundle is traction-compressed into a tape, and then cooled and formed through a refrigeration tunnel. The fiber filaments of the glass fiber prepreg tape or the carbon fiber prepreg tape are even layers with at least two layers and opposite winding directions. The winding tension of each layer is 3 to 50 N, the winding angle is 25 to 75 °, and the winding tension decreases by 5% from the inside outwards. The glass fiber prepreg tape or the carbon fiber prepreg tape is preheated before and after winding through tunnel heating, and the preheating temperature is 250 °C to 300 °C.

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