CN108758118A - A kind of deep-sea flexible composite pipe - Google Patents

Abstract

The invention discloses a deep-sea flexible composite pipe. The deep-sea flexible composite pipe is a comprehensive flexible composite pipe. Compared with the traditional reinforced thermoplastic composite pipe, a metal bellows inner liner, a compression-resistant outer reinforcement layer and a tensile strength are added. Among them, the former can effectively prevent the inner pipe from collapsing caused by high-temperature medium and negative pressure inside the pipe, the middle one can provide higher hoop stiffness for the composite pipe to resist high external pressure load in deep sea, and the latter can withstand dynamic loads such as wind, wave and current; at the same time, according to The structural characteristics of each layer optimize the connection mode between layers to ensure that the functions of each layer are fully utilized, ensuring that the deep-sea flexible composite pipe of the present invention not only has the ability to be suitable for deep-sea operations, but also meets the minimum bending radius and minimum bending radius of traditional reinforced thermoplastic composite pipes. Performance requirements for coilability.

Description

A deep-sea flexible composite pipe

technical field

The invention relates to a reinforced thermoplastic composite pipe, in particular to a deep-sea flexible composite pipe suitable for deep-sea operations.

Background technique

Reinforced Thermoplastic Pipe (RTP) is a newly developed plastic pipe in the world in recent years. Its main feature is that it can withstand high working pressure while maintaining a certain flexibility of polyethylene pipe. Advantages, it can be made into a coil (coiled tubing), and the length of each coil ranges from tens of meters to nearly a thousand meters. It has been widely used in land and some shallow sea oil and natural gas exploitation, high-pressure long-distance natural gas transmission and various high-pressure transmission Medium pipeline field. The main feature of reinforced thermoplastic composite pipe is that the pipe wall is composed of three layers. Usually, the inner layer is a corrosion-resistant and wear-resistant polyolefin inner pipe (mostly PE at present); the middle layer is a reinforcing material layer, and various high-strength materials can be used. Synthetic fibers (such as aramid fibers), inorganic fibers (such as glass fibers, basalt fibers), steel wires, etc. are first made into reinforcing belts or steel belts are used directly, and reinforced by winding; the outer layer is generally polyolefin (mostly PE at present). Protective layer (such as anti-scratch, antistatic, flame retardant, etc.) to meet different application requirements; but for deep sea environment and dynamic working conditions of marine risers, conventional reinforced thermoplastic composite pipes cannot meet the high external pressure and high temperature medium in deep sea , Operating requirements under strong axial load and dynamic load.

Contents of the invention

In order to solve the above technical problems, the present invention designs a deep-sea flexible composite pipe suitable for deep-sea operations.

The present invention adopts following technical scheme:

A deep-sea flexible composite pipe, its structure includes an inner lining layer, a functional layer, an inner lining sealing layer, a compression outer reinforcement layer, a functional layer, a compression inner reinforcement layer, an anti-wear layer, a tensile layer, and a functional layer from the inside to the outside. Layer, outer protective layer; each layer is spirally wound or bonded to form a composite pipe, the inner lining layer is a metal bellows structure, and the compressive outer reinforcement layer is a spiral winding lock structure. The inner lining is a metal bellows structure with anti-corrosion properties, which can not only effectively prevent the inner pipe from collapsing caused by high-temperature medium and negative pressure in the pipe, but also meet the bending performance requirements of the composite pipe and have a long service life; Provide high hoop stiffness, so that the flexible composite pipe has a strong ability to resist external pressure; and meet the minimum bending radius and coilable performance requirements of reinforced thermoplastic composite pipes.

Preferably, the cross-section of the metal bellows structure of the inner liner is U-shaped or Ω-shaped.

Preferably, the functional layer is formed by winding multiple parallel layers of polyester tapes with sealing properties. The functional layer mainly assists the setting of adjacent thermoplastic pipes; at the same time, it can isolate the metal layer (compressive reinforcement layer, tensile layer) and reduce the friction between adjacent layers to improve the fatigue life of the flexible composite pipe.

Preferably, the inner lining sealing layer, wear-resistant layer and outer protective layer are thermoplastic pipes. Thermoplastic pipes have the functions of corrosion resistance, wear resistance, scratch resistance, weather resistance, flame retardant, antistatic, etc. Materials with specific functions can be selected according to the characteristics of the conveying medium or the external environment, such as polyethylene (PE), polypropylene ( PP), heat-resistant polyethylene (PERT), POK, PVDF, nylon (PA), etc.

Preferably, the cross-section of the helically wound locking structure may be a double-layer interlocking U-shaped structure or a single-layer self-locking lying Z-shaped structure.

Preferably, each layer of the helically wound locking structure is helically wound along the axial direction of the tube leaving a certain gap for sliding.

Preferably, the pressure-resistant internal reinforcement layer is a solid pipe bonded by glass fibers.

Preferably, the glass fiber bonded solid pipe can be formed by direct winding and bonding of glass fibers, or can be formed by winding and bonding layer by layer of glass fiber prepreg tapes.

Preferably, the tensile layer is formed by helically winding even layers of flat steel bars, the winding directions of adjacent layers are opposite, and each layer of flat steel bars is helically wound along the pipe axis leaving a gap. The single-layer coverage rate of the flat steel bar is greater than 75%, the winding angle is determined according to geometric mechanics, and the single-layer thickness, width and number of winding layers are determined according to the axial load requirements.

As a preference, each structural layer of the deep-sea flexible composite pipe can be increased or decreased according to actual working conditions. For dynamic standpipes or pipelines with axial strength requirements, the tensile layer and its adjacent layers—wear layer and functional layer must be added; for high-temperature media or negative pressure conditions, the inner lining and its relative Neighboring layers—functional layers must also be added.

The beneficial effects of the present invention are: a deep-sea flexible composite pipe of the present invention is a multifunctional flexible composite pipe. Compared with the traditional reinforced thermoplastic composite pipe, a metal Tensile layers, the former can effectively prevent the high-temperature medium and the negative pressure inside the pipe from causing the inner pipe to collapse, the middle one can provide the composite pipe with higher hoop stiffness and resist high external pressure loads in deep sea, and the latter can withstand dynamic loads such as wind, waves and currents; at the same time According to the structural characteristics of each layer, the connection mode between layers is optimized to ensure that the functions of each layer are fully utilized, and the deep-sea flexible composite pipe of the present invention not only has the ability to be suitable for deep-sea operations, but also meets the minimum bending radius of traditional reinforced thermoplastic composite pipes and coilability performance requirements.

Description of drawings

Fig. 1 is a kind of cross-sectional view of the present invention;

Fig. 2 is a kind of structural representation of the present invention;

Fig. 3 is another kind of structural representation of the present invention;

Fig. 4 is a kind of structural representation of the lying Z-shaped lock structure of the compressive outer reinforcing layer in the present invention;

Fig. 5 is a kind of structural representation of the U-shaped buckle structure of the compressive outer reinforcement layer in the present invention;

Fig. 6 is a kind of structural representation of tensile layer in the present invention;

Fig. 7 is a schematic structural view of a dynamic riser suitable for transporting non-high-temperature medium in deep sea according to the present invention;

Fig. 8 is a schematic structural view of a static pipe used for conveying high-temperature medium in deep sea according to the present invention;

Fig. 9 is a schematic structural view of a static pipe suitable for conveying non-high-temperature medium in deep sea according to the present invention;

In the figure: 1. Inner lining layer, 2. Functional layer, 3. Lining sealing layer, 4. Compression-resistant outer reinforcement layer, 4-1. Locking structure, 4-2. Locking gap, 5. Functional layer, 6. Compression inner reinforcing layer, 7. Anti-wear layer, 8. Tensile layer, 8-1. Flat steel bar, 9. Functional layer, 10. Outer protective layer.

Detailed ways

Below by specific embodiment, in conjunction with accompanying drawing, the technical solution of the present invention is described in further detail:

Embodiment 1: As shown in the accompanying drawings 1-3, a deep-sea flexible composite pipe of this embodiment has multi-functional performance, and is suitable for a dynamic riser for transporting high-temperature medium in deep sea. The structure includes inner lining layer 1, Functional layer 2, lining sealing layer 3, compressive outer reinforcing layer 4, functional layer 5, compressive inner reinforcing layer 6, wear-resistant layer 7, tensile layer 8, functional layer 9, outer protective layer 10; The reinforced thermoplastic composite pipe is formed by spiral winding or bonding; the inner lining layer 1 is a metal bellows structure with anti-corrosion performance and meets the bending requirements of the composite pipe, which can effectively prevent the inner pipe from collapsing caused by high-temperature medium and negative pressure inside the pipe. U-shaped or Ω-shaped cross-section is preferred; functional layer 2 is made of polyester tape with sealing properties and is wound in parallel in multiple layers to seal inner lining layer 1; inner lining sealing layer 3, wear-resistant layer 7 and outer protective layer 10 are thermoplastic pipes, which have the functions of corrosion resistance, wear resistance, scratch resistance, weather resistance, flame retardant, antistatic, etc. Materials with specific functions can be selected according to the characteristics of the conveying medium or the external environment, such as polyethylene (PE) , polypropylene (PP), heat-resistant polyethylene (PERT), nylon (PA), POK, PVDF, etc.; the external compression reinforcement layer is a spiral wound lock structure 4-1, which not only provides high hoop stiffness for the pipeline , so that the flexible composite pipe has a strong ability to resist external pressure; and meet the minimum bending radius and coilable performance requirements of the reinforced thermoplastic composite pipe, as shown in Figure 4 and Figure 5, the locking form includes double-layer Interlocking U-shaped structure and single-layer self-locking horizontal Z-shaped structure, and each layer of locking structure 4-1 is spirally wound along the tube axis to leave a certain locking gap 4-2, which can slide; functional layer 5, 8. Like the functional layer 2, it is made of polyester tapes with sealing properties, which are multi-layered in parallel and overlapped. The isolated metal layer (compressive reinforcement layer, tensile layer) reduces the friction between adjacent layers and improves the fatigue life of the flexible composite pipe; The compression inner reinforcement layer 6 is a solid pipe bonded by glass fibers, which can be formed by direct winding and bonding of glass fibers or by winding and bonding layer by layer of glass fiber prepreg tape; as shown in Figure 6 It shows that the tensile layer 9 is spirally wound by an even number of layers of flat steel bars 8-1, and the winding directions of adjacent layers are opposite, and each layer of flat steel bars is spirally wound along the tube axis to leave a gap; the coverage rate of a single layer is greater than 75%, The winding angle is determined according to geometric mechanics, and the thickness, width and number of winding layers of a single layer are determined according to the requirements of axial load; finally, a thermoplastic outer protective layer 10 is covered.

Embodiment 2: As shown in Figure 7, a deep-sea flexible composite pipe of this embodiment is suitable for a dynamic riser for deep-sea transportation of non-high-temperature media. The structure refers to Embodiment 1, and the inner liner 1 and functional layer 2 are removed. From inside to outside, it includes lining sealing layer 3, compression outer reinforcement layer 4, functional layer 5, compression inner reinforcement layer 6, wear-resistant layer 7, tensile layer 8, functional layer 9, outer protective layer 10, and each layer Helically wound or bonded to each other to form a reinforced thermoplastic composite pipe.

Embodiment 3: As shown in Figure 8, a deep-sea flexible composite pipe of this embodiment is suitable for static pipes transporting high-temperature media in deep sea, without the need to bear high axial loads; the structure refers to Embodiment 1, and the wear-resistant layer is removed 7. Tensile layer 8, functional layer 9, including inner lining layer 1, functional layer 2, inner lining sealing layer 3, compression outer reinforcement layer 4, functional layer 5, compression inner reinforcement layer 6, outer The protective layer 10 is spirally wound or bonded to each other to form a reinforced thermoplastic composite pipe.

Embodiment 4: As shown in Figure 9, a deep-sea flexible composite pipe of this embodiment is suitable for static pipes that transport non-high-temperature media in deep sea. The structure refers to Embodiment 1, and the inner lining layer 1, functional layer 2, and anti-corrosion pipe are removed. Abrasive layer 7, tensile layer 8, and functional layer 9, including lining sealing layer 3, compressive outer reinforcing layer 4, functional layer 5, compressive inner reinforcing layer 6, and outer protective layer 10 from the inside to the outside. Helically wound or bonded to each other to form a reinforced thermoplastic composite pipe.

The deep-sea flexible composite pipe of the present invention is a multifunctional flexible composite pipe. Compared with the traditional reinforced thermoplastic composite pipe, a metal bellows inner liner, a compression-resistant outer reinforcement layer and a tensile layer are added, wherein the former can effectively Prevent the high-temperature medium and negative pressure inside the pipe from causing the inner pipe to collapse. The middle one provides a higher hoop stiffness for the composite pipe and resists high external pressure loads in the deep sea. The latter can withstand dynamic loads such as wind, waves and currents; at the same time, optimize the interlayer according to the structural characteristics of each layer The connection mode ensures that the functions of each layer are fully utilized, and the deep-sea flexible composite pipe of the present invention not only has the ability to be suitable for deep-sea operations, but also meets the minimum bending radius and coilability performance requirements of traditional reinforced thermoplastic composite pipes ; At the same time, considering the design requirements and economy, the corresponding structural layers can be increased or decreased by design.

The embodiment described above is only a preferred solution of the present invention, and does not limit the present invention in any form. There are other variations and modifications on the premise of not exceeding the technical solution described in the claims.

Claims (10)

1. A deep-sea flexible composite pipe is characterized in that its structure includes an inner liner, a functional layer, a lining sealing layer, a compression outer reinforcement layer, a functional layer, a compression inner reinforcement layer, and an anti-wear layer from the inside to the outside. , Tensile layer, functional layer, and outer protective layer; each layer is spirally wound or bonded to form a composite pipe, the inner lining layer is a metal bellows structure, and the compressive outer reinforcement layer is a spiral wound lock structure. 2. A deep-sea flexible composite pipe according to claim 1, characterized in that, the cross-section of the metal bellows structure of the inner lining layer is U-shaped or Ω-shaped. 3. A deep-sea flexible composite pipe according to claim 1, characterized in that the functional layer is formed by parallel overlapping winding of multiple layers of polyester tape with sealing properties. 4. A deep-sea flexible composite pipe according to claim 1, characterized in that the inner lining sealing layer, wear-resistant layer and outer protective layer are thermoplastic pipes. 5. A deep-sea flexible composite pipe according to claim 1, characterized in that the cross-section of the helically wound locking structure can be a double-layer interlocking U-shaped structure or a single-layer self-locking horizontal Z-shaped structure . 6 . The deep-sea flexible composite pipe according to claim 1 , characterized in that, each layer of the helically wound locking structure is helically wound along the axial direction of the pipe to leave a certain gap, which can slide. 7. A deep-sea flexible composite pipe according to claim 1, characterized in that, the pressure-resistant internal reinforcement layer is a solid pipe bonded by glass fibers. 8. A deep-sea flexible composite pipe according to claim 7, characterized in that, the glass fiber bonded solid pipe can be formed by direct winding and bonding of glass fibers or by winding and bonding of multi-layer glass fiber prepreg tapes. Bonded in layers. 9. A deep-sea flexible composite pipe according to claim 1, characterized in that, the tensile layer is formed by helically winding even layers of flat steel bars, the winding directions of adjacent layers are opposite, and each layer of flat steel bars runs along the length of the pipe. The axial helical winding leaves a gap. 10. The deep-sea flexible composite pipe according to claim 1, characterized in that, each structural layer of the deep-sea flexible composite pipe can increase or decrease the corresponding structural layers according to actual working conditions.