Deep sea flexible coiled tubing structure

Abstract

The utility model provides a deep-sea flexible continuous pipe structure which solves the technical problems that due to the fact that the direction and size of ocean current waves are uncertain, the pipe is usually bent into a C shape or an S shape in the side direction under the action of surge and water flow impact force, and the influence on a pipeline is serious, and can be widely applied to the field of deep-sea transportation. The pipe wall of the pipe is sequentially provided with a lining layer, a compensation enhancement layer, a framework layer, an isolation layer, a spiral enhancement layer and an outer protection layer from inside to outside. The lining layer is made of ultra-high molecular weight polyethylene, and the compensation reinforcing layer is formed by curing a front layer of equal-thickness high-strength high-modulus fiber and a back layer of equal-thickness high-strength high-modulus fiber and resin and is continuously wound on the outer side of the lining layer; the framework layer is formed by curing high-strength high-modulus fibers and resin, and the isolating layer is made of polyethylene; the spiral reinforcing layer is made of glass fiber reinforced plastics or aramid fibers, the outer protective layer is made of PE or PU plastics, optical fibers and optical fiber sensors are further arranged in the pipe wall, and the optical fiber sensors are arranged at intervals and connected through the optical fibers.

Description

Technical Field

[0001] The invention belongs to the technical field of deep-sea transportation, and in particular relates to a deep-sea flexible continuous pipe structure. Background Art

[0002] Since the design standards of deep-sea pipelines are much higher than those of land pipelines, and because the environment of submarine pipelines is more complex and difficult to control than that of land, it is necessary to consider not only the buoyancy of the pipeline and the external pressure of deep-sea water, but also the dynamic effects of ocean currents, waves, and tides on the pipeline. The "Research on Key Technologies of Non-metallic Non-adhesive Flexible Mixed Pipes for Deep-sea Mining" project, a key special project of the "14th Five-Year Plan" National Key R&D Program "Key Technologies and Equipment for Deep Sea and Polar Regions" undertaken by China University of Petroleum (Beijing), has been approved and established, with the project number 2022YFC2803700, which has far-reaching significance for the exploration of deep-sea pipelines.

[0003] Due to the uncertain direction and size of ocean current waves, and the impact of surges and water flow, the pipes are often arched into C-shaped or S-shaped laterally, which has a serious impact on the pipeline. Flexible pipelines have complex structures and are subject to a variety of loads, making it difficult to detect structural damage in a timely manner; extreme loads have a great impact on the safety of pipeline structures, and it is difficult to monitor the location of pipeline leaks. Among them, the transportation of minerals in mining causes severe wear and tear on the inside of the pipe, and even excessive wear and tear, bumps or leaks, which will cause irreversible damage to the pipe and even lead to the scrapping of the pipe. Summary of the invention

[0004] The purpose of the present invention is to solve the deficiencies of the above-mentioned technology and provide a deep-sea flexible continuous pipe structure.

[0005] To this end, the present invention provides a deep-sea flexible continuous pipe structure, wherein the pipe wall is composed of an inner lining layer, a compensation reinforcement layer, a skeleton layer, an isolation layer, a spiral reinforcement layer, and an outer protective layer from the inside to the outside;

[0006] The material of the inner lining layer is ultra-high molecular weight polyethylene, the compensation reinforcement layer is made of high-strength and high-modulus fibers of equal thickness and resin solidified on both sides, and is circumferentially and continuously wound around the outside of the inner lining layer at an angle of 45-60 degrees; the skeleton layer is made of high-strength and high-modulus fibers and resin solidified, and is circumferentially and continuously wound around the outside of the reinforcement layer at an angle of 40-70 degrees; the isolation layer is made of polyethylene, and the spiral reinforcement layer is made of fiberglass or aramid, and is circumferentially and continuously wound around the outside of the isolation layer at an angle of 30-50 degrees, and is distributed in a left and right double spiral. The outer protective layer is made of PE or PU plastic;

[0007] Optical fibers and optical fiber sensors are also arranged inside the pipe wall. The optical fiber sensors are arranged at intervals and connected by optical fibers to detect whether the pipe wall is broken.

[0008] A spiral groove is provided on the outer surface of the inner lining layer, and the optical fiber and the optical fiber sensor are arranged inside the spiral groove and then fixed by a flexible resin.

[0009] The optical fiber and the optical fiber sensor may also be arranged in the compensation enhancement layer.

[0010] Furthermore, in the winding process of the compensation reinforcement layer, space is reserved to wind the optical fiber and the optical fiber sensor into the compensation reinforcement layer.

[0011] Furthermore, each layer structure adopts a non-bonding process.

[0012] The present invention provides a deep-sea flexible continuous pipe structure, which has the following beneficial effects:

[0013] The present invention has a non-bonded continuous pipe structure with the advantages of small bending radius, corrosion resistance, large design space and light weight. It has low cost and can work in deep sea conditions within 6000m. The non-metallic design greatly reduces the overall weight of the pipeline.

[0014] By setting up optical fiber and optical fiber sensor, liquid can be detected to send out alarm signals, and then the location of pipeline rupture can be determined and the pipeline can be repaired. By setting up spiral grooves, the bending radius of the pipe can be increased. When the pipe is transported, the harder pipe can be coiled and placed to reduce storage space. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a diagram of the interior of the tube wall of Example 1 of the present invention;

[0016] Figure 2 is a diagram of the interior of the tube wall of Example 2 of the present invention;

[0017] Figure 3 is a cross-sectional view of a tube wall of Example 2 of the present invention;

[0018] Markings in the figure: 1. lining layer; 2. compensation reinforcement layer; 3. skeleton layer; 4. isolation layer; 5. spiral reinforcement layer; 6. outer protective layer; 7. optical fiber; 8. spiral groove. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments to help understand the content of the present invention. The methods used in the present invention are all conventional methods unless otherwise specified; the raw materials and devices used are all conventional commercial products unless otherwise specified.

[0020] The present invention provides a deep-sea flexible continuous pipe structure, wherein the pipe wall comprises an inner lining layer 1, a compensation reinforcement layer 2, a skeleton layer 3, an isolation layer 4, a spiral reinforcement layer 5, and an outer protective layer 6 from the inside to the outside.

[0021] The material of the inner lining layer 1 is ultra-high molecular weight polyethylene. As the inner wall of the pipeline in direct contact with the mineral medium transported by the pipeline, the material has high strength and good wear resistance, and can effectively extend the service life of the inner lining layer 1.

[0022] The compensation reinforcement layer 2 is made of high-strength and high-modulus fibers of equal thickness and solidified with resin in both positive and negative directions, and is continuously wound around the outer side of the inner lining layer 1 in a small pitch of 50 degrees, so as to protect the inner lining layer 1, increase the strength of the inner lining layer 1, and withstand the circumferential stress.

[0023] The skeleton layer 3 is the force-bearing basis of the entire flexible pipe. It is made of high-strength and high-modulus fibers and solidified resin. It is continuously wound around the outside of the reinforcement layer with a small pitch of 55 degrees to bear the radial force of the entire flexible pipe.

[0024] The isolation layer 4 is made of polyethylene. Because deep-sea operations are dynamic conditions, the layers of the pipe are in a state of mutual squeezing due to the multiple effects of waves, deep-sea pressure and its own weight. The dynamic conditions also cause a certain amount of sliding friction between the layers, resulting in local heating. The use of polyethylene material can reduce the friction coefficient and play a good role in isolation and lubrication.

[0025] The spiral reinforcement layer 5 is made of glass fiber reinforced plastics or aramid fiber, and is continuously wound around the outside of the isolation layer with a large pitch of 40 degrees, and is distributed in a left and right double helix to balance the axial torsion and withstand the axial tension.

[0026] The outer protective layer 6 is made of a polymer corrosion-resistant material, such as PE, PU plastic, and has the functions of anti-corrosion, wear resistance, anti-external penetration, and protection of the pipe.

[0027] Each layer of the structure is manufactured using a non-bonding process, distributing the functions to the corresponding layers. While ensuring the functions, the non-bonding process can also achieve the flexibility of the tube for easy coiling and storage.

[0028] It also includes an optical fiber 7 and an optical fiber sensor. The optical fiber sensor is arranged at a certain distance on the inner wall of the pipe and connected by the optical fiber 7. When the inner wall of the pipe is severely worn and penetrated, seawater penetrates into the inner compensation reinforcement layer 2 under the action of pressure. The optical fiber sensor in the spiral groove 8 senses the salinity of the seawater and collects the signal feedback. The damaged position can be known and an alarm can be issued to prevent further losses.

[0029] The optical fiber sensor uses a detection probe with a volume similar to that of the optical fiber. In one embodiment, the detection probe uses a salinity detection probe, which has a detection range of more than 1.0 mol / L by outputting different light intensities in different salinity environments. Based on this characteristic, the detection probe can output light of different intensities after seawater intrusion to determine whether it has been invaded by seawater.

[0030] It should be noted that the detection probe of the optical fiber sensor can measure different parameters in the pipe wall according to actual needs, such as a temperature detection probe and a pressure detection probe.

[0031] Embodiment 1:

[0032] like Figure 1 As shown, a spiral groove 8 is provided on the outer surface of the inner lining layer 1, and the optical fiber 7 and the optical fiber sensor are arranged inside the spiral groove 8 and then fixed by a flexible resin. By providing the spiral groove 8, the bending radius of the pipe can be increased, and when the pipe is transported, the relatively hard pipe can be coiled and placed to reduce the storage space.

[0033] Embodiment 2:

[0034] like Figure 2 , as shown in FIG3 , the optical fiber 7 and the optical fiber sensor are arranged in the compensation reinforcement layer 2. In the winding process of the compensation reinforcement layer 2, a space is reserved to wind the optical fiber 7 and the optical fiber sensor in the compensation reinforcement layer 2. By arranging the optical fiber 7 in the compensation reinforcement layer 2, the loss of the structural strength of the inner lining layer 1 when the groove is opened can be avoided, and the service life is longer.

[0035] In the description of the present invention, it should be understood that the terms "left", "right", "up", "down", "top", "bottom", "front", "back", "inside", "outside", "back", "middle", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0036] However, what is described above is only a specific embodiment of the present invention and should not be used to limit the scope of implementation of the present invention. Therefore, the replacement of equivalent components, or equivalent changes and modifications made according to the scope of protection of the present invention should still fall within the scope covered by the claims of the present invention.

Claims

1. A deep-sea flexible continuous pipe structure, characterized in that: The pipe wall from inside to outside is composed of inner lining layer, compensation reinforcement layer, skeleton layer, isolation layer, spiral reinforcement layer and outer protective layer. The material of the inner lining layer is ultra-high molecular weight polyethylene, the compensation reinforcement layer is made of high-strength and high-modulus fibers of equal thickness and resin solidified on both sides, and is circumferentially and continuously wound around the outside of the inner lining layer at an angle of 45-60 degrees; the skeleton layer is made of high-strength and high-modulus fibers and resin solidified, and is circumferentially and continuously wound around the outside of the reinforcement layer at an angle of 40-70 degrees; the isolation layer is made of polyethylene, and the spiral reinforcement layer is made of fiberglass or aramid, and is circumferentially and continuously wound around the outside of the isolation layer at an angle of 30-50 degrees, and is distributed in a left and right double spiral. The outer protective layer is made of PE or PU plastic; Optical fibers and optical fiber sensors are also arranged inside the pipe wall. The optical fiber sensors are arranged at intervals and connected by optical fibers to detect whether the pipe wall is broken.

2. A deep-sea flexible continuous pipe structure according to claim 1, characterized in that: A spiral groove is provided on the outer surface of the inner lining layer, and the optical fiber and the optical fiber sensor are arranged inside the spiral groove.

3. A deep-sea flexible continuous pipe structure according to claim 1, characterized in that: The optical fiber and the optical fiber sensor are arranged in the compensation enhancement layer.

4. A deep-sea flexible continuous pipe structure according to any one of claims 1 to 3, characterized in that: Each layer of the structure adopts a non-bonded process.

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