Deep sea flexible composite pipe with integrated multilayer structure

Abstract

The utility model relates to the technical field of composite pipeline terminal, specifically relates to integrated multilayer structure's deep sea flexible composite pipeline, deep sea flexible composite pipeline includes the inner layer, first reinforcing layer, metal shielding layer, second reinforcing layer and outer layer that are sequentially compounded from inside to outside along the radial direction, the inner layer is used for directly contacting and conveying deep sea oil gas or special fluid, first reinforcing layer is used for bearing the internal pressure of conveying medium, metal shielding layer is used for blocking the invasion of external medium and auxiliary pressure bearing, second reinforcing layer is used for bearing deep sea external pressure and guaranteeing flexibility, the outer layer is used for external environment protection, and the targeted reinforcement hoop extrusion resistance extrusion strength is greater than or equal to 120MPa, guarantee pipeline minimum bending radius less than or equal to 10 times pipe diameter simultaneously, adapt reel laying, realize high pressure resistance under the premise, still keep higher curling capacity.

Description

Technical Field

[0001] This utility model relates to the field of composite pipeline terminal technology, specifically to a deep-sea flexible composite pipeline with an integrated multi-layer structure. Background Technology

[0002] As deep-sea oil and gas exploration and development advances to deeper waters, flexible composite pipelines have become one of the core equipment for deep-sea fluid transportation due to their advantages such as flexible laying and adaptability to complex seabed topography. Existing deep-sea flexible composite pipelines typically adopt a basic composite structure of inner layer-reinforcement layer-outer layer. The inner layer is mostly made of ordinary polyolefin or fluoroplastic to contact the transported medium, the reinforcement layer is mostly made of glass fiber or ordinary carbon fiber to bear the internal or external pressure requirements, and the outer layer is mainly made of ordinary polyethylene to achieve basic environmental protection. However, the deep-sea environment presents multiple harsh conditions such as high pressure, strong corrosion and dynamic loads, which puts forward extremely high requirements for the coordinated performance of each layer of the pipeline.

[0003] In existing technologies, the fiber weaving angle, pitch and material specifications of the reinforcing layer lack specificity, making it difficult to balance internal pressure bearing capacity, external pressure resistance and flexibility at the same time. This leads to some pipelines experiencing local overload fractures under high pressure, or being unable to adapt to the roll-up of pipelaying vessels due to excessive rigidity. Therefore, an integrated multi-layer deep-sea flexible composite pipeline has been proposed. Utility Model Content

[0004] In order to solve the technical problems existing in the prior art, the present invention provides an integrated multi-layer deep-sea flexible composite pipeline.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution: an integrated multi-layer deep-sea flexible composite pipeline, the deep-sea flexible composite pipeline comprising an inner layer, a first reinforcing layer, a metal shielding layer, a second reinforcing layer, and an outer layer arranged radially from the inside to the outside; the inner layer is used to directly contact and transport deep-sea oil and gas or special fluids; the first reinforcing layer is used to withstand the internal pressure of the transported medium; the metal shielding layer is used to block the intrusion of external media and assist in pressure bearing; the second reinforcing layer is used to withstand the external external pressure and ensure flexibility; the outer layer is used for external environmental protection.

[0006] Preferably, the inner layer of the deep-sea flexible composite pipeline is formed by extrusion of perfluoroalkoxyalkane (PFA), and the thickness of the inner layer is 2-5 mm with a thickness tolerance of ≤ ±0.2 mm.

[0007] Preferably, the first reinforcing layer of the deep-sea flexible composite pipeline is formed by weaving T800 grade carbon fiber along the pipeline axis at an angle of ±45°, the carbon fiber weaving pitch of the first reinforcing layer is 1.2-1.5 times the outer diameter of the pipeline, and the carbon fiber thickness of the first reinforcing layer is 5-8 mm.

[0008] Preferably, the metal shielding layer of the deep-sea flexible composite pipeline is made of Hastelloy C276 strip spirally wound, the strip width of the metal shielding layer is 20-50mm, and the strip thickness of the metal shielding layer is 0.5-1mm.

[0009] Preferably, the second reinforcing layer of the deep-sea flexible composite pipeline is woven from Kevlar 129 aramid fiber at an angle of ±30° along the circumference of the pipeline, the weaving density of the second reinforcing layer is 10-15 strands per centimeter, and the thickness of the second reinforcing layer is 3-6 mm.

[0010] Preferably, the outer layer of the deep-sea flexible composite pipeline is made of cross-linked polyethylene (XLPE) injection molding, the degree of cross-linking of the outer layer is ≥70%, and the thickness of the outer layer is 3-5mm.

[0011] Preferably, an adhesive layer is provided between the inner layer and the first reinforcing layer, and between the first reinforcing layer and the metal shielding layer of the deep-sea flexible composite pipeline, and the adhesive layer is made of modified ethylene-vinyl acetate copolymer (EVA).

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows: 1. In this utility model, the first reinforcing layer is made of T800 grade carbon fiber with ±45° weaving, and the combination of 1.2-1.5 times the outer diameter pitch and 5-8mm thickness can efficiently transmit and disperse the radial force generated by internal pressure. The tensile strength is ≥5000MPa, which meets the requirements of high pressure transmission. The second reinforcing layer is made of Kevlar 129 aramid fiber with ±30° weaving and a density design of 10-15 strands per centimeter. It specifically strengthens the circumferential compression resistance, with a compression strength of ≥120MPa. At the same time, it ensures that the minimum bending radius of the pipeline is ≤10 times the pipe diameter, which is suitable for roll laying. Under the premise of high pressure resistance, it still maintains a high bending capacity. Attached Figure Description

[0013] Figure 1 This is a three-dimensional hierarchical diagram of the present invention.

[0014] The numbers in the diagram represent: 1. Inner layer; 2. First reinforcement layer; 3. Metal shielding layer; 4. Second reinforcement layer; 5. Outer layer. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments, highlighting the above and other technical features and advantages of the present invention. However, the following embodiments are merely preferred embodiments of the present invention and are not exhaustive. Example

[0016] like Figure 1As shown, an integrated multi-layered deep-sea flexible composite pipeline comprises an inner layer, a first reinforcing layer, a metal shielding layer, a second reinforcing layer, and an outer layer arranged radially from the inside out. The inner layer is used to directly contact and transport deep-sea oil and gas or special fluids. The inner layer of the deep-sea flexible composite pipeline is extruded from perfluoroalkoxyalkane (PFA). PFA material itself has excellent oil resistance and chemical corrosion resistance, and can directly withstand corrosive media such as sulfides, acids, and alkalis in deep-sea oil and gas. The thickness of the inner layer is 2-5mm. The 2-5mm thickness design ensures the structural strength of the transport cavity while avoiding excessive thickness that would increase the rigidity of the pipeline. The thickness tolerance of the inner layer is ≤±0.2mm. The thickness tolerance of ≤±0.2mm ensures that the inner layer and the first reinforcing layer are tightly bonded, reducing interlayer gaps and avoiding the risk of local stress concentration or media leakage caused by gaps under deep-sea high pressure.

[0017] The first reinforcing layer is used to withstand the internal pressure of the transported medium. The first reinforcing layer of the deep-sea flexible composite pipeline is formed by weaving T800 grade carbon fiber at an angle of ±45° along the pipeline axis. Weaving at an angle of ±45° can simultaneously resist the radial force generated by the internal pressure of the transported medium and the shear force when the pipeline is bent, which is suitable for high-pressure transportation scenarios in deep-sea oil and gas extraction. The carbon fiber weaving pitch of the first reinforcing layer is 1.2-1.5 times the outer diameter of the pipeline. The weaving pitch of 1.2-1.5 times the outer diameter balances the uniformity of the stress on the fiber bundle and the flexibility of the pipeline, avoiding excessive rigidity due to too small a pitch or insufficient strength due to too large a pitch. The carbon fiber thickness of the first reinforcing layer is 5-8mm. The 5-8mm thickness design can ensure that the first reinforcing layer provides sufficient internal pressure bearing capacity, while coordinating with other layers to control the overall weight of the pipeline, which is convenient for deep-sea laying. The metal shielding layer is used to block the intrusion of external media and assist in pressure bearing. The metal shielding layer of the deep-sea flexible composite pipeline is made of Hastelloy C276 tape spirally wound. Hastelloy C276 has extremely strong corrosion resistance to seawater and deep-sea microbial secretions, which can effectively block the intrusion of external media into the inner layer. The tape width of the metal shielding layer is 20-50mm. The tape width of 20-50mm and the overlap of 15%-20% can form a leak-free physical barrier through continuous winding, while avoiding the increase of pipeline bending resistance caused by excessive overlap. The tape thickness of the metal shielding layer is 0.5-1mm. The thickness of 0.5-1mm ensures auxiliary pressure bearing while taking into account the flexibility of the metal layer, adapting to the requirements of pipeline coiling and laying. The second reinforcing layer is used to withstand deep-sea external pressure and ensure flexibility. The second reinforcing layer of the deep-sea flexible composite pipeline is woven with Kevlar 129 aramid fiber at a ±30° angle along the circumference of the pipeline. Weaving at a ±30° angle can effectively resist the circumferential force generated by deep-sea water pressure and prevent the pipeline from being crushed. The weaving density of the second reinforcing layer is 10-15 strands per centimeter. The weaving density of 10-15 strands per centimeter ensures that the fiber bundles are evenly distributed and reduces weak points. The thickness of the second reinforcing layer is 3-6mm. The 3-6mm thickness design provides sufficient resistance to external pressure while ensuring that the minimum bending radius of the pipeline is ≤10 times the pipe diameter through the flexible weaving structure, which is suitable for pipelaying vessel drum storage and underwater robot operation. The outer layer is used for external environmental protection. The outer layer of the deep-sea flexible composite pipeline is made of cross-linked polyethylene (XLPE) injection molding. The cross-linking degree of the outer layer is ≥70%. The cross-linking degree of ≥70% can make XLPE form a stable three-dimensional network structure, which significantly improves its resistance to environmental stress cracking. The thickness of the outer layer is 3-5mm. The thickness of 3-5mm can effectively isolate the internal structure from the erosion of seawater and silt, and will not affect the overall flexibility of the pipeline due to excessive thickness.

[0018] An adhesive layer is provided between the inner layer and the first reinforcing layer, and between the first reinforcing layer and the metal shielding layer of the deep-sea flexible composite pipeline. The adhesive layer is made of modified ethylene-vinyl acetate copolymer (EVA). Modified EVA has excellent bonding properties, which can ensure a tight bond between the inner layer and the first reinforcing layer, and between the first reinforcing layer and the metal shielding layer, avoiding interlayer separation in the dynamic environment of the deep sea. EVA material has good compatibility with PFA, carbon fiber and Hastelloy, and the bonding strength will not decrease due to interfacial reaction when immersed in seawater for a long time, thus ensuring the integrity and strength stability of the pipeline structure.

[0019] The above description is merely a preferred embodiment of the present utility model and is illustrative rather than restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present utility model, all of which will fall within the protection scope of the present utility model.

Claims

1. An integrated multi-layered deep-sea flexible composite pipeline, characterized in that, The deep-sea flexible composite pipeline comprises an inner layer, a first reinforcing layer, a metal shielding layer, a second reinforcing layer, and an outer layer arranged radially from the inside to the outside. The inner layer is used to directly contact and transport deep-sea oil and gas or special fluids. The first reinforcing layer is used to withstand the internal pressure of the transported medium. The metal shielding layer is used to block the intrusion of external media and assist in bearing pressure. The second reinforcing layer is used to withstand the external pressure in deep sea and ensure flexibility. The outer layer is used for external environmental protection.

2. The integrated multi-layer deep-sea flexible composite pipeline as described in claim 1, characterized in that, The inner layer of the deep-sea flexible composite pipeline is formed by extrusion of perfluoroalkoxyalkane (PFA), and the thickness of the inner layer is 2-5 mm with a thickness tolerance of ≤ ±0.2 mm.

3. The integrated multi-layer deep-sea flexible composite pipeline as described in claim 1, characterized in that, The first reinforcing layer of the deep-sea flexible composite pipeline is formed by weaving T800 grade carbon fiber along the pipeline axis at an angle of ±45°. The carbon fiber weaving pitch of the first reinforcing layer is 1.2-1.5 times the outer diameter of the pipeline, and the carbon fiber thickness of the first reinforcing layer is 5-8 mm.

4. The integrated multi-layer deep-sea flexible composite pipeline as described in claim 1, characterized in that, The metal shielding layer of the deep-sea flexible composite pipeline is made of Hastelloy C276 strip spirally wound, the strip width of the metal shielding layer is 20-50mm, and the strip thickness of the metal shielding layer is 0.5-1mm.

5. The integrated multi-layer deep-sea flexible composite pipeline as described in claim 1, characterized in that, The second reinforcing layer of the deep-sea flexible composite pipeline is made of Kevlar 129 aramid fiber woven along the circumference of the pipeline at an angle of ±30°. The weaving density of the second reinforcing layer is 10-15 strands per centimeter, and the thickness of the second reinforcing layer is 3-6 mm.

6. The integrated multi-layer deep-sea flexible composite pipeline as described in claim 1, characterized in that, The outer layer of the deep-sea flexible composite pipeline is made of cross-linked polyethylene (XLPE) injection molding, the degree of cross-linking of the outer layer is ≥70%, and the thickness of the outer layer is 3-5mm.

7. The integrated multi-layer deep-sea flexible composite pipeline as described in claim 1, characterized in that, An adhesive layer is provided between the inner layer and the first reinforcing layer of the deep-sea flexible composite pipeline, and between the first reinforcing layer and the metal shielding layer. The adhesive layer is made of modified ethylene-vinyl acetate copolymer (EVA).

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