Composite pipeline

Abstract

The utility model provides a composite pipeline. The composite pipeline sequentially comprises an inner pipe and an outer pipe from inside to outside, the outer framework layer comprises a steel wire wound outside the inner pipe in a spiral mode, and the steel wire and the inner pipe are connected through an embedded material in a hot melting bonding mode; the steel belt winding layer is wound on the outer side of the outer framework layer in a spiral mode; and the outer side of the steel belt winding layer is coated with the coating layer. The outer framework layer and the inner pipe are connected through the embedding material in a hot melting bonding mode, the embedding material enables the steel wires to be firmly attached to the inner pipe in the hot melting bonding mode, the high bonding strength between layers is ensured through the hot melting bonding connection mode, sliding or separation between the layers is avoided, and the internal pressure resistance and the external pressure resistance are enhanced. Meanwhile, the outer framework layer is matched with the steel belt winding layer, so that the internal pressure resistance and the external pressure resistance of the composite pipeline are remarkably enhanced, the dynamic stability is improved, and the composite pipeline has the technical effects of high strength, dynamic stability and corrosion resistance.

Description

TECHNICAL FIELD

[0001] The utility model relates to pipeline technical field especially, relate to a kind of composite pipeline. BACKGROUND

[0002] With the increasing requirements of industrial pipeline system on pressure resistance, corrosion resistance, flexibility and life performance, traditional single-layer metal pipe or plastic pipe has been difficult to meet the use demand under high strength, high load and high corrosive environment. For this reason, composite material pipeline technology gradually becomes the hotspot of research and application.

[0003] Composite pipeline is usually composed of multiple materials, and its structure usually includes inner pipe, intermediate reinforcing layer and outer coating layer. The inner pipe plays a role in fluid transportation, the intermediate reinforcing layer is used to improve the mechanical strength of the pipeline, and the outer coating layer is used to protect against external environmental erosion.

[0004] Among them, how to enhance the overall mechanical properties of composite pipeline through the intermediate reinforcing layer to meet its environmental pressure requirements is a subject that the industry needs to consider.

[0005] It should be noted that the information disclosed in the above background section is only used to strengthen the understanding of the background of the utility model, and therefore can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0006] In view of the problems in the prior art, the purpose of the utility model is to provide a composite pipeline, which overcomes the difficulties of the prior art and can solve the technical problem of insufficient mechanical properties of composite pipeline in related technology.

[0007] The disclosed embodiment provides a composite pipeline, which comprises the following layers in order from inside to outside:

[0008] An inner pipe;

[0009] An outer skeleton layer comprising steel wires wound in a spiral manner outside the inner pipe, the steel wires and the inner pipe being connected by an embedding material in a hot melt adhesive manner;

[0010] A steel belt winding layer wound in a spiral manner outside the outer skeleton layer;

[0011] A coating layer coated outside the steel belt winding layer.

[0012] In an optional embodiment, the outer skeleton layer comprises a copper plating layer outside the steel wires, and the steel wires and the inner pipe are connected by the embedding material in a hot melt adhesive manner through the copper plating layer.

[0013] In an optional embodiment, the spiral winding angle of at least one of the outer skeleton layer and the steel belt winding layer is 35°-80°.

[0014] In an optional embodiment, the outer skeleton layer comprises a plurality of steel wires wound in a spiral manner outside the inner tube, and adjacent two of the steel wires are connected by the embedding material in a hot melt adhesive manner.

[0015] In an optional embodiment, the outer skeleton layer is a multi-layer structure, and adjacent two layers from inside to outside are connected by the embedding material in a hot melt adhesive manner.

[0016] In an optional embodiment, the steel belt winding layer is wound outside the outer skeleton layer by winding tension.

[0017] In an optional embodiment, the steel belt winding layer is a multi-layer structure, and adjacent two layers from inside to outside are cross-wound in a spiral manner; or the multi-layer structure comprises an inner layer group and an outer layer group outside the inner layer group, wherein each side layer group comprises at least two layers and has the same spiral winding direction, and the inner layer group and the outer layer group are arranged to have opposite spiral winding directions.

[0018] In an optional embodiment, the thickness of each layer in the multi-layer structure is 0.3-3 mm.

[0019] In an optional embodiment, the cladding layer extends axially from one end of the composite pipe to the other end.

[0020] In an optional embodiment, the composite pipe further comprises an isolation layer arranged between the steel belt winding layer and the cladding layer, for limiting the steel belt winding layer from protruding radially outward along the composite pipe.

[0021] In an optional embodiment, the isolation layer adopts a plastic tape layer.

[0022] The composite pipe according to the embodiments of the present disclosure has the following advantages:

[0023] The composite pipe comprises, from inside to outside, an inner pipe, an outer framework layer comprising steel wires wound in a spiral manner outside the inner pipe, the steel wires being connected to the inner pipe by an embedded material in a hot melt adhesive manner, a steel belt winding layer wound in a spiral manner outside the outer framework layer, and a cladding layer cladded outside the steel belt winding layer.

[0024] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0025] Other features, objects, and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments read in conjunction with the accompanying drawings.

[0026] Figure 1 A partial cross-sectional view of the composite pipe according to an embodiment of the present disclosure.

[0027] Figure 2 An axial projection view of the composite pipe according to an embodiment of the present disclosure, which corresponds to the partial cross-sectional view shown in FIG. 1; Figure 1

[0028] Figure 3 Another axial projection view of another composite pipe according to an embodiment of the present disclosure.

[0029] REFERENCE NUMERALS

[0030] 1, inner pipe; 2, outer framework layer; 20, steel wire; 3, 3', steel belt winding layer; 30, steel belt; 4, cladding layer; 5, isolation layer. DETAILED DESCRIPTION

[0031] ​Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations can be implemented in any

[0032] Moreover, the drawings are not necessarily to scale. Like numbers refer to like, similar or analogous items and steps throughout the drawings and text. Some of the blocks in the drawings can be functional building blocks, and can not necessarily correspond to a physical or logical entity. These functional building blocks can be implemented in software, or in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0033] In the existing pipe reinforcement technology, a single reinforcement material or a simple winding structure is usually used, such as a large-angle hoop reinforcement or an outer winding steel belt. However, these structures face many challenges under high pressure and dynamic environment. First, the structural coverage of the reinforcement structure in the conventional pipe is low, which leads to insufficient mechanical properties and makes it difficult to withstand high internal pressure, high external pressure and buoyancy at the same time. Second, the existing reinforcement structure is mostly non-composite design, directly wound or fixed by mechanical means, lacking a stable connection mechanism, and is prone to failure under dynamic load (such as sea waves, vortex-induced vibration).

[0034] To solve these problems, the present disclosure provides a new type of composite pipe, which overcomes the shortcomings of the prior art through the synergistic reinforcement design of a multi-layer structure, combined with hot melt bonding and non-fixed steel belt winding, and has significant advantages in structural complexity, mechanical properties and environmental adaptability compared to the prior art.

[0035] As shown in FIGS. 1A and 1B, the composite pipe of the present disclosure comprises the following layers from inside to outside: Figure 1 and Figure 2 As shown in FIGS. 1A and 1B, the composite pipe of the present disclosure comprises the following layers from inside to outside:

[0036] An inner pipe 1;

[0037] An outer framework layer 2 comprising steel wires 20 wound in a spiral manner outside the inner pipe 1, the steel wires 20 and the inner pipe 1 being connected by hot melt bonding through the embedding material;

[0038] A steel belt winding layer 3 wound in a spiral manner outside the outer framework layer 2;

[0039] A cladding layer 4 cladded outside the steel belt winding layer 3.

[0040] The inner tube 1 is the innermost layer of the composite pipe and directly contacts the conveying medium, providing initial sealing and corrosion resistance to ensure the safety and stability of the medium during transportation. The inner tube 1 can be made of polymer materials such as polyethylene (PE), cross-linked polyethylene (XLPE), heat-resistant polyethylene, nylon, polyvinylidene fluoride (PVDF), or polyphenylene sulfide (PPS) to ensure excellent chemical stability and wear resistance.

[0041] In this embodiment, to improve the resistance to external pressure and the ability to partially withstand internal pressure of the inner tube 1, a steel wire framework layer is added outside the inner tube 1 as an outer framework layer 2 to share the structural strength. The steel wire 20 is spirally wound outside the inner tube 1, and the steel wire 20 is connected with the inner tube 1 by hot melt bonding of the embedded material. The embedded material firmly attaches the steel wire 20 to the inner tube 1 by hot melt bonding, and the hot melt bonding connection ensures high interlayer bonding strength. The outer framework layer 2 and the inner tube 1 form an integral structure, significantly improving the hoop and axial strength of the inner tube 1, avoiding interlayer sliding or separation, enhancing the resistance to internal and external pressure, and improving dynamic stability. In this way, the outer framework layer 2 enables the inner tube 1 to withstand high internal and external pressure, ensuring the stability and safety of the composite pipe in a high-pressure environment and maintaining structural integrity under dynamic load (such as vortex-induced vibration), reducing the risk of failure in a dynamic environment.

[0042] The steel belt winding layer 3 is spirally installed outside the outer framework layer 2, further enhancing the overall rigidity, stability, and external pressure resistance of the pipe, while increasing the weight of the pipe to improve underwater stability, especially in deep water environments against buoyancy and vortex-induced vibration.

[0043] The coating layer 4 is wrapped outside the steel belt winding layer 3 as the outermost layer, providing external protection for the composite pipe, preventing environmental erosion (such as seawater corrosion) and mechanical damage, and prolonging the service life of the pipe.

[0044] Therefore, the disclosed embodiment has the technical effects of significantly enhancing the resistance to internal and external pressure of the composite pipe, improving dynamic stability, and making the composite pipe have high strength, dynamic stability, and corrosion resistance through the reasonable design and connection method of the above multi-layer composite structure, the cooperation of the outer framework layer 2 and the steel belt winding layer 3, and the hot melt bonding between the outer framework layer 2 and the inner tube 1.

[0045] In this embodiment, the outer framework layer 2 includes a plurality of steel wires 20, which can be a single steel wire or a steel cord composed of two or more steel wires.

[0046] In the disclosed embodiment, the outer framework layer 2 is wound outside the inner tube 1 by the following method:

[0047] The inner tube 1 (for example, high density polyethylene HDPE (High Definition Polyethylene) is selected) is fixed on the rotating mandrel of the winding device to provide a stable winding base and ensure the surface of the inner tube is clean and free of impurities.

[0048] A plurality of high-strength steel wires 20 are selected, and polymer resin is embedded between the steel wires 20. The plurality of steel wires 20 are arranged side by side and embedded with the polymer resin to form a unidirectional tape. Optionally, the surface of the steel wires 20 is coated with copper to form a copper plating layer (not shown in the figure) to enhance corrosion resistance and adhesion. The polymer resin is at least one of polyethylene, cross-linked polyethylene, and nylon, which is the same as or compatible with the material of the inner tube 1, to ensure the effect of hot melt adhesion.

[0049] Next, the steel wires 20 and the polymer resin are embedded by an extrusion or calendering process using a special device to form a unidirectional tape with uniform width. Optionally, the tape is stored in a constant temperature environment before winding to avoid changes in material properties and ensure that the tape has sufficient strength, toughness, and adhesion performance to meet the requirements of spiral winding.

[0050] Subsequently, the parameters of the winding device are adjusted, including the winding angle, rotation speed, pulling force, and preheating temperature. For example, the winding angle is set to 35°-80° according to design requirements to optimize the mechanical properties in the hoop and axial directions, and 50°-60° can be used as the initial angle, and the specific angle is determined by mechanical calculation. The rotation speed of the mandrel is set according to the diameter of the inner tube 1 and the width of the tape to ensure uniform winding of the steel wires 20. The pulling force is used to control the tension of the tape to avoid over-tightening that causes deformation of the inner tube or over-looseness that causes poor adhesion. The preheating temperature of the surface of the inner tube is preheated to near the melting point of the polymer resin to prepare for hot melt adhesion.

[0051] After that, the composite tape composed of the steel wires 20 and the polymer resin is wound in a spiral manner on the outside of the inner tube 1, and hot melt adhesion is achieved by heating.

[0052] Then, one end of the tape is fixed at the starting position of the inner tube 1, and the tape is guided to wind at a set angle by the guiding device of the winding device. The tape is wound continuously and uniformly to ensure that there is no obvious gap or overlap between adjacent tapes. During the winding process, an infrared heater or a hot air device is used to locally heat the winding area to melt the polymer resin and form a firm hot melt adhesion with the surface of the inner tube 1, and also form a firmer hot melt adhesion between adjacent steel wires 20.

[0053] After winding one layer of the outer skeleton layer 2, the coverage and adhesion quality are checked, and the tension or temperature is adjusted as needed to form a uniform outer skeleton layer 2 to ensure the mechanical properties and interlayer bonding strength.

[0054] Optionally, if the outer skeleton layer 2 is designed as a multi-layer structure, the above winding step can be repeated to wind additional outer skeleton layers 2, and then the winding direction of the wound outer skeleton layer 2 can be the same as or opposite to the previous layer (cross winding) to enhance the overall mechanical properties. In this way, the compression and tensile properties of the pipeline are further improved through the multi-layer structure to meet the demand of high-pressure environment.

[0055] In addition, after winding each layer, the adhesive area is solidified by a cooling device (such as air cooling) to avoid the accumulation of thermal stress, and the mandrel is kept rotating during the cooling process to prevent the pipeline from deforming.

[0056] Finally, after the winding of the outer skeleton layer 2 is completed, the wound area is cooled to completely solidify the hot melt adhesive area to form a composite material that not only connects the inner tube 1 and the outer skeleton layer 2 in a hot melt adhesive manner, but also connects adjacent steel wires 20, and when the outer skeleton layer 2 is a multi-layer structure, it connects adjacent two layers from the inside to the outside of the multi-layer structure, ensuring the stability between the layers.

[0057] In this embodiment, if the outer skeleton layer 2 includes a copper plating layer outside the steel wire 20, the steel wire 20 is connected between the copper plating layer and the inner tube 1 by the composite material in a hot melt adhesive manner. The steel wire 20 with a copper plating layer improves corrosion resistance and adhesion, and the embedded polymer resin enhances strength and stability, improving overall performance.

[0058] The polymer resin embedded between the multiple steel wires during the manufacturing process melts and cools to form a composite material during the subsequent hot melt process, which actually wraps the multiple steel wires 20 to form a compact strip structure, and the compact structure enhances the reliability of hot melt adhesion, prevents the steel wires 20 from spreading or shifting, and improves its mechanical properties. Optionally, the steel wires 20 can also be partially wrapped or supported in a grid shape.

[0059] In the embodiments of the present disclosure, the spiral winding angle of the outer skeleton layer 2 is 35°-80°. This range is determined based on the optimization requirements of the circumferential and axial mechanical properties, which can provide good strength and stability under high internal and external pressure conditions, and adapt to the requirements of deep water marine environment.

[0060] In the embodiments of the present disclosure, the steel belt winding layer 3 is wound on the outside of the outer skeleton layer 2 by winding tension. At this time, the steel belt winding layer 3 is wound by winding tension, and the non-adhesive structure between the steel belt winding layer 3 and the outer skeleton layer 2, and the spiral winding of the steel belt 30 forms a tight external support using winding tension.

[0061] The gap between the steel belts 30 caused by the winding tension is the key to the dynamic adaptability of the steel belt winding layer 3, which supports the design goal of relying on the winding tension as mentioned above. The existence of the gap allows the steel belts 30 to have a certain degree of freedom during winding, and the non-fixed design of the winding tension allows the steel belts 30 to have a certain degree of adjustment under dynamic load, allowing limited interlayer slip, absorbing the stress caused by dynamic load (such as vortex-induced vibration), reducing stress concentration, thereby prolonging the service life of the pipeline and enhancing the performance of the pipeline in a dynamic environment.

[0062] Alternatively, the steel belt winding layer 3 can also be designed as tightly arranged steel belts, for example, adjusting the size of the gap or using different winding densities.

[0063] In the embodiments of the present disclosure, the helical winding angle of the steel belt winding layer 3 is 35°-80°. This angle range is coordinated with the design of the carcass layer 2, ensuring that the steel belts 30 enhance the dynamic stability and external pressure resistance of the pipeline while providing internal pressure resistance and counterweight functions, maintaining the overall stability of the pipeline. The angle is selected based on the optimized design of the aforementioned carcass layer 2, stabilizing the structure of the carcass layer 2, adapting to different load and depth conditions, for example, significantly improving stability under vortex-induced vibration.

[0064] In the embodiments of the present disclosure, the steel belt winding layer 3 is a multi-layer structure, and adjacent two layers from the inside to the outside are helically wound in a cross manner. This design is based on the extension of the aforementioned 35°-80° angle range, with different directions (for example, clockwise and counterclockwise) winding through the multi-layer structure, and the cross winding increases the interlayer interlacing strength, forming a mesh-like reinforcing structure, and the torsional and bending resistance is improved, thereby further improving the mechanical properties and maintaining the shape stability of the pipeline under dynamic load.

[0065] In the embodiments of the present disclosure, the thickness of each layer of steel belt in the multi-layer structure is 0.3-3.0mm, which ensures sufficient strength and weight.

[0066] The winding method of the steel belt winding layer 3 can refer to the description of the carcass layer 2, which will not be described in detail here.

[0067] In the embodiments of the present disclosure, the composite pipeline further comprises: a separation layer 5 arranged between the steel belt winding layer 3 and the cladding layer 4, for limiting the steel belt winding layer 3 from protruding outward along the radial direction of the composite pipeline. The separation layer 5 can not bear the mechanical structure requirements, and its function is to prevent the relative movement of the steel belts 30 during the bending process of the composite pipeline from generating shear force on the external cladding layer 4, protecting the cladding layer 4 from being broken.

[0068] In this embodiment, the isolation layer 5 is made of plastic tape, such as polyester plastic tape, which does not bear structural strength, preventing the relative movement of the steel belt 30 under the action of bending or dynamic load (such as sea waves, vortex-induced vibration) from causing shear to the outer polyethylene coating, resulting in the rupture of the coating layer 4. Among them, the material of the isolation layer 5 is usually PET film, including but not limited to tensile strength, tear strength and temperature resistance, to ensure stability in extreme environments.

[0069] In an alternative way, the isolation layer 5 can be a single-layer structure or a multi-layer structure, which ensures that it does not bear structural strength and can reduce direct contact between the steel belt 30 and the coating layer 4, protecting the coating layer 4 from mechanical damage and prolonging the service life of the pipeline, while improving the stability of the pipeline in a dynamic environment.

[0070] In an alternative way, the thickness of the isolation layer 5 is uniform, forming a physical barrier. This feature is a refinement of the protection function of the isolation layer 5, supporting the design goal of the single-layer structure. The uniform thickness ensures the consistency of the isolation layer 5 on the entire surface of the pipeline, forming a stable physical barrier, and the uniform thickness of the isolation layer prevents local failure or weak points, ensuring the overall stability of the pipeline in high pressure and dynamic environments, further enhancing the protection effect.

[0071] In the embodiments of the present disclosure, the coating layer 4 is used to effectively isolate the pipeline structure inside it from the external harsh environment (such as sea salt, ultraviolet rays), reduce corrosion and wear, and prolong the service life of the pipeline, while protecting the pipeline structure inside it from physical damage.

[0072] Optionally, the coating layer 4 is made of polymer materials such as high-density polyethylene, which has excellent weather resistance and mechanical protection performance.

[0073] In the embodiments of the present disclosure, the coating layer 4 extends axially (continuously) from one end of the composite pipeline to the other end, so that it forms a gapless coverage in the circumferential direction. The axial continuous extension and circumferential gapless coverage of this embodiment design is a refinement of the protection function of the coating layer 4, and the gapless coverage prevents seawater penetration, ensuring that the external protection has no leaks.

[0074] Optionally, the coating layer 4 can also use segmented coverage.

[0075] As shown in Figure 3 The embodiments of the present disclosure also provide another composite pipeline, in which the steel belt winding layer 3' is also designed as a multi-layer structure. Compared with Figure 1 , the difference between the composite pipeline shown in Figure 3 is that:

[0076] In the multi-layer structure, the adjacent two layers of steel strips on the inner side have the same spiral winding direction, the adjacent two layers of steel strips on the outer side have the same spiral winding direction, and the spiral winding direction of the adjacent two layers of steel strips on the inner side is opposite to that of the adjacent two layers of steel strips on the outer side.

[0077] The adjacent two layers of steel strips on the inner side have the same spiral winding direction, which can provide consistent circumferential reinforcement and preliminary resistance to internal pressure. The adjacent two layers of steel strips on the inner side have the same spiral winding direction, which can further enhance the rigidity and resistance to external pressure of the pipeline.

[0078] Further, the spiral winding direction of the adjacent two layers of steel strips on the inner side is opposite to that of the adjacent two layers of steel strips on the outer side, forming an inner-outer cross winding mode. This design optimizes the mechanical distribution of the pipeline under dynamic load by contrasting the inner-outer winding directions.

[0079] In the corresponding embodiments, the multi-layer structure of the steel strip winding layer 3' can be divided into an inner side layer group 3a and an outer side layer group 3b outside the inner side layer group 3a, each side layer group comprising at least two layers and having the same spiral winding direction (e.g., clockwise or counterclockwise), and the spiral winding direction of the inner side layer group 3a and the outer side layer group 3b is opposite, e.g., one side layer group is clockwise and the other side layer group is counterclockwise.

[0080] In another embodiment, the multi-layer structure of the steel strip winding layer can also be divided into more groups, and the winding direction of each group can be designed in other ways as needed, which is not limited here.

[0081] Other embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. The present disclosure is intended to cover any variations, uses, or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure that come within known or customary practice in the art to which the application pertains. The specification and examples are to be regarded as exemplary only, and the true scope and spirit of the application are indicated by the appended claims.

Claims

1. A composite pipe, characterized by, From inside to outside, the composite pipe comprises the following layers in sequence: an inner tube (1); an outer framework layer (2) comprising steel wires (20) spirally wound outside the inner tube (1), the steel wires (20) and the inner tube (1) being connected by an embedding material in a hot melt adhesive manner; a steel band winding layer (3) spirally wound outside the outer framework layer (2); a cladding layer (4) cladded outside the steel band winding layer (3).

2. The composite pipe of claim 1, wherein, The outer framework layer (2) comprises a copper plating layer outside the steel wires (20), the steel wires (20) and the inner tube (1) being connected by the embedding material in a hot melt adhesive manner through the copper plating layer.

3. The composite pipe of claim 1, wherein, The spiral winding angle of at least one of the outer framework layer (2) and the steel band winding layer (3) is 35°-80°.

4. The composite pipe of claim 1, wherein, The outer framework layer (2) comprises a plurality of the steel wires (20) spirally wound outside the inner tube (1), the adjacent two steel wires (20) being embedded and connected by the embedding material in a hot melt adhesive manner.

5. The composite pipe of claim 1, wherein, The outer framework layer (2) is a multi-layer structure, the adjacent two layers of the multi-layer structure being connected by the embedding material in a hot melt adhesive manner from inside to outside.

6. The composite pipe of claim 1, wherein, The steel band winding layer (3) is wound outside the outer framework layer (2) by winding tension.

7. The composite pipe of claim 1, wherein, The steel band winding layer (3) is a multi-layer structure, the adjacent two layers of the multi-layer structure being spirally wound in a cross manner from inside to outside; or, the multi-layer structure comprises an inner layer group and an outer layer group outside the inner layer group, each of the layer groups comprising at least two layers and having the same spiral winding direction, the inner layer group and the outer layer group being arranged to have opposite spiral winding directions.

8. The composite pipe of claim 7, wherein, The thickness of each layer of the multi-layer structure is 0.3-3mm.

9. The composite pipe of claim 1, wherein, The cladding layer (4) extends axially from one end of the composite pipe to the other end.

10. The composite pipe of claim 1, wherein, The composite pipe further comprises an isolation layer (5) arranged between the steel band winding layer (3) and the cladding layer (4) for limiting the steel band winding layer (3) from protruding radially outward along the composite pipe.

11. The composite pipe of claim 10, wherein, The isolation layer (5) is a plastic tape layer.

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