CN115614561A - A high temperature resistant non-bonded flexible composite pipeline and its manufacturing method - Google Patents

Abstract

The invention discloses a high-temperature-resistant non-bonding flexible composite pipeline and a manufacturing method. The pipeline is sequentially provided with a skeleton layer, a sacrificial layer, an internal pressure sealing layer, a pressure-resistant armor layer, a first auxiliary layer, and a second auxiliary layer. A tensile armor layer, a second auxiliary layer, a second tensile armor layer, a third auxiliary layer, and an outer cladding layer, each layer is non-adhesively connected, and is produced layer by layer from the inside to the outside; the present invention uses The PTFE high temperature resistant tape is used as a sacrificial layer to replace the sacrificial layer made of extruded polyvinylidene fluoride material, which reduces a vinylidene fluoride extrusion process in pipeline production, because the thickness of the PTFE high temperature resistant tape is thin , so that the overall shrinkage of each layer of the pipeline means that the overall cross-sectional area of the pipeline is reduced, thereby further reducing the weight of the pipeline and reducing the cost of pipeline materials. Cost of production of flexible composite pipelines.

Description

A high temperature resistant non-bonded flexible composite pipeline and its manufacturing method

technical field

The invention relates to a pipeline and a manufacturing method, in particular to a high-temperature-resistant non-bonding flexible composite pipeline and a manufacturing method, belonging to the technical field of marine oil and gas medium transportation.

Background technique

Submarine pipeline is the main carrier of offshore oil and gas transportation. As an upgraded product of steel pipe, flexible pipeline has the characteristics of high flexibility, low construction cost, strong corrosion resistance, strong terrain adaptability and reusability, and is suitable for offshore oil and gas exploitation. Various pipeline applications such as mixed transportation, oil transportation, gas transportation, water injection, chemical agents, deep-sea risers and jumper pipes. At present, more and more oilfield developments will consider the use of unbonded flexible pipelines instead of steel pipes. Because flexible pipelines are easier and quicker to install than steel pipes, if flexible pipelines are used instead of steel pipes in oilfield development, it will save a lot of offshore construction costs.

The conventional internal pressure sealing layer material of the marine flexible pipeline is a non-metallic material. The selection of this material is affected by the temperature of the medium transported inside the pipeline. The non-metallic material commonly used for high-temperature medium transmission is polyvinylidene fluoride. Due to the particularity of this material, When selecting the material of this layer, in order to ensure the safety of the pipeline, it is necessary to design a two-layer structure, one of which is used as a sacrificial layer. Due to the high cost of polyvinylidene fluoride material, the sacrificial layer of polyvinylidene fluoride material increases the length of the entire pipeline. pipeline cost.

It is against this background that this patent application proposes a high temperature resistant non-bonding flexible composite pipeline and its manufacturing method.

Contents of the invention

The main purpose of the present invention is to overcome the above-mentioned shortcomings existing in the prior art, and provide a high-temperature-resistant non-bonding flexible composite pipeline and a manufacturing method.

The present invention is achieved by the following technical solutions:

A high temperature resistant non-bonded flexible composite pipeline, comprising a skeleton layer, a sacrificial layer, an internal pressure sealing layer, a compressive armor layer, a first auxiliary layer, a first tensile armor layer, a second auxiliary layer, a second Tensile armor layer, third auxiliary layer, outer cladding layer;

The skeleton layer is located at the innermost part of the pipeline, and the skeleton layer is made of S-shaped interlocking stainless steel strips. The width of the skeleton layer can be adjusted within the range of 20-60 mm, and the winding angle of the skeleton layer is 90 degrees;

The sacrificial layer is non-bonded and wound on the outside of the skeleton layer. The sacrificial layer is made of polytetrafluoroethylene high temperature resistant tape. The width of the sacrificial layer can be adjusted within the range of 50-90 mm. The thickness of the sacrificial layer Adjustable in the range of 0.4~2mm;

The internal pressure sealing layer is coated on the outside of the sacrificial layer through extrusion non-bonding, and the internal pressure sealing layer is made of polyvinylidene fluoride;

The anti-compression armor layer is made of carbon steel strip, and the anti-compression armor layer is wound on the outside of the internal pressure sealing layer by alternating positive and negative helical non-bonded carbon steel strips, and the anti-compression armor layer The layer winding angle can be adjusted in the range of 80~90 degrees, the width of the compressive armor layer can be adjusted in the range of 20~90 mm, and the thickness of the compressive armor layer can be adjusted in the range of 0.5~1.5 mm;

The first auxiliary layer is spirally and non-adhesively wound on the outside of the pressure-resistant armor layer, the first auxiliary layer is made of plastic tape, and the width of the first auxiliary layer can be adjusted within the range of 60-90 mm. The thickness of the first auxiliary layer is adjustable within the range of 0.1-1 mm, and the winding angle of the first auxiliary layer is adjustable within the range of 50-90 degrees;

The first tensile armor layer is made of a flat steel strip, and the first tensile armor layer is wound on the outside of the first auxiliary layer by a flat steel strip, which is alternately helical and non-adhesive. The width of the first tensile armor layer is adjustable within the range of 5-15 mm, the thickness of the first tensile armor layer is adjustable within the range of 2-7 mm, and the winding angle of the first tensile armor layer is between Adjustable within the range of 20~55 degrees;

The second auxiliary layer is non-adhesively wound on the outside of the first tensile armor layer, the second auxiliary layer is made of any one of glass fiber tape, polyester tape and aramid tape, and the second The width of the auxiliary layer is adjustable within the range of 60-90 mm, the thickness of the second auxiliary layer is adjustable within the range of 0.3-1 mm, and the winding angle of the second auxiliary layer is adjustable within the range of 50-90 degrees;

The second tensile armor layer is made of a flat steel strip, and the second tensile armor layer is wound on the outside of the second auxiliary layer by a flat steel strip, which is alternately helical and non-bonding. The width of the second tensile armor layer is adjustable within the range of 5-15 mm, the thickness of the second tensile armor layer is adjustable within the range of 2-7 mm, and the winding angle of the second tensile armor layer is between Adjustable within the range of 20~55 degrees;

The third auxiliary layer is non-bonded and wound on the outside of the second tensile armor layer. The third auxiliary layer is made of any one of glass fiber tape, polyester tape and aramid tape. The third The width of the auxiliary layer is adjustable within the range of 60-90 mm, the thickness of the third auxiliary layer is adjustable within the range of 0.3-1 mm, and the winding angle of the third auxiliary layer is adjustable within the range of 50-90 degrees;

The outer cladding layer is coated on the outside of the third auxiliary layer through extrusion non-bonding, and the outer cladding layer is made of any one of medium density polyethylene, high density polyethylene and nylon.

The present invention also relates to a method for manufacturing a high-temperature-resistant non-bonding flexible composite pipeline. The manufacturing method includes the following steps:

Step S1: High temperature resistant non-bonded flexible composite pipeline is produced layer by layer from inside to outside;

Step S2: The skeleton layer is made of stainless steel strips, and the manufacturing is realized by pressing and interlocking forming with a locking machine;

Step S3: The sacrificial layer is made of polytetrafluoroethylene high-temperature-resistant tape, and after the production process of the skeleton layer, the polytetrafluoroethylene high-temperature-resistant tape is spirally wound to the outside of the skeleton layer by a high-temperature tape winding machine;

Step S4: The internal pressure sealing layer is made of polyvinylidene fluoride pellets. After the production process of the sacrificial layer, the polyvinylidene fluoride pellets are melted through an extruder, and the polyvinylidene fluoride is coated on the polyvinylidene fluoride through a mold. outside the sacrificial layer;

Step S5: The compressive armor layer is made of carbon steel strips, and after the production process of the internal pressure sealing layer, the carbon steel strips are alternately helically wound to the outside of the internal pressure sealing layer by a steel strip winding machine;

Step S6: The first auxiliary layer is made of plastic tape, and after the production process of the compressive armor layer, the plastic tape is spirally wound to the outside of the compressive armor layer by a wrapping machine;

Step S7: The first tensile armor layer is made of flat steel strips, and after the production process of the first auxiliary layer, the flat steel strips are alternately helically wound to the first auxiliary layer by a flat steel winding machine outside;

Step S8: The second auxiliary layer is made of a high-strength plastic tape of any one of glass fiber tape, polyester tape and aramid tape. After the production process of the first tensile armor layer, the high-strength plastic tape is wrapped by a wrapping machine. helically wound to the outside of the first tensile armor layer;

Step S9: The second tensile armor layer is made of flat steel strips, and after the production process of the second auxiliary layer, the flat steel strips are alternately helically wound to the second auxiliary layer by a flat steel winding machine outside;

Step S10: The third auxiliary layer is made of a high-strength plastic tape of any one of glass fiber tape, polyester tape and aramid tape. After the second tensile armor layer production process, the high-strength plastic tape is wrapped by a wrapping machine. helically wound onto the outside of said second tensile armor layer;

Step S11: The outer cladding layer is made of polymer material pellets of any one of medium-density polyethylene, high-density polyethylene and nylon, and after the third auxiliary layer production process, the The high-molecular polymer pellets are melted, and the high-molecular polymer is coated on the outside of the third auxiliary layer through the mold.

Beneficial effects of the present invention:

The invention discloses a high-temperature-resistant non-bonding flexible composite pipeline and its manufacturing method, using a spirally wound polytetrafluoroethylene high-temperature-resistant tape as a sacrificial layer instead of a sacrificial layer made of extruded polyvinylidene fluoride material, reducing A polyvinylidene fluoride extrusion process in the pipeline production process is introduced. At the same time, due to the thin thickness of the PTFE high temperature resistant belt, the overall shrinkage of each layer of the pipeline, that is, the overall cross-sectional area of the pipeline is reduced, and the weight of the pipeline is further reduced. The cost of materials, on the basis of ensuring the safety and effectiveness of the pipeline's high-temperature medium underwater transportation, effectively reduces the production cost of the submarine non-bonded flexible composite pipeline.

The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Description of drawings

Fig. 1 is a schematic diagram of the pipeline of the preferred embodiment of the present invention.

The marks of the components in the drawings are as follows: 1. Skeleton layer; 2. Sacrificial layer; 3. Internal pressure sealing layer; 4. Compression-resistant armor layer; 5. First auxiliary layer; 6. First tensile armor layer ; 7, the second auxiliary layer; 8, the second tensile armor layer; 9, the third auxiliary layer; 10, the outer cladding layer.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in Figure 1, a high temperature resistant non-bonded flexible composite pipeline includes a skeleton layer 1, a sacrificial layer 2, an internal pressure sealing layer 3, a compressive armor layer 4, a first auxiliary layer 5, a first tensile The armor layer 6, the second auxiliary layer 7, the second tensile armor layer 8, the third auxiliary layer 9, and the outer cladding layer 10, the above layers are non-adhesively connected; the skeleton layer 1 is located in the innermost part of the pipeline, and this layer It plays the role of supporting the overall structure of the pipeline. The skeleton layer 1 is made of S-shaped interlocking stainless steel strips. The width of the skeleton layer 1 can be adjusted within the range of 20-60 mm. The winding angle of the skeleton layer 1 is 90 degrees; the sacrificial layer 2 is non-adhesive The knot is wound on the outside of the skeleton layer 1. In order to reduce the stress concentration effect of the internal pressure sealing layer during extrusion, the sacrificial layer 2 is made of polytetrafluoroethylene high temperature resistant tape. The width of the sacrificial layer 2 can be within the range of 50-90 mm. Adjustable, the thickness of the sacrificial layer 2 can be adjusted within the range of 0.4~2 mm; the internal pressure sealing layer 3 is coated on the outside of the sacrificial layer 2 through extrusion and non-adhesive, this layer plays a role in sealing the conveying medium, and the internal pressure sealing layer 3 It is made of polyvinylidene fluoride; the compressive armor layer 4 is made of carbon steel strips, which play the role of bearing internal and external pressure, and the compressive armor layer 4 is made of carbon steel strips with alternating positive and negative spirals. Bonded and wound on the outside of the internal pressure sealing layer 3, the winding angle of the compression armor layer 4 can be adjusted within the range of 80~90 degrees, the width of the compression armor layer 4 can be adjusted within the range of 20~90 mm, and the compression armor layer 4 The thickness of layer 4 can be adjusted within the range of 0.5~1.5 mm; the first auxiliary layer 5 is helically and non-adhesively wound on the outside of the pressure-resistant armor layer 4, and this layer acts as a restraint on the inner layer structure, and at the same time, avoids the production and transshipment process In order to prevent wear and tear on the inner layer structure, the first auxiliary layer 5 is made of plastic tape, the width of the first auxiliary layer 5 can be adjusted within the range of 60-90 mm, and the thickness of the first auxiliary layer 5 can be adjusted within the range of 0.1-1 mm , the winding angle of the first auxiliary layer 5 can be adjusted within the range of 50~90 degrees; the first tensile armor layer 6 is made of flat steel strips, and the first tensile armor layer 6 is made of flat steel strips alternately Spiral non-adhesive winding on the outside of the first auxiliary layer 5, this layer bears the axial tension, the width of the first tensile armor layer 6 can be adjusted within the range of 5-15 mm, and the thickness of the first tensile armor layer 6 is 2 It can be adjusted in the range of ~7mm, and the winding angle of the first tensile armor layer 6 can be adjusted in the range of 20~55 degrees; the second auxiliary layer 7 is non-adhesively wound on the outside of the first tensile armor layer 6, and the second The auxiliary layer 7 is made of any one of glass fiber tape, polyester tape and aramid tape, and this layer plays the role of binding the first tensile armor layer to prevent the first tensile armor layer from buckling or "bird cage” failure, the width of the second auxiliary layer 7 can be adjusted within the range of 60-90 mm, the thickness of the second auxiliary layer 7 can be adjusted within the range of 0.3-1 mm, and the winding angle of the second auxiliary layer 7 can be adjusted within the range of 50-90 degrees Adjustable; the second tensile armor layer 8 is made of flat steel strips, and the second tensile armor layer 8 is wound on the outside of the second auxiliary layer 7 by alternating positive and negative spirals of flat steel strips. Undertake the axial tension, the width of the second tensile armor layer 8 can be adjusted within the range of 5-15 mm, and the thickness of the second tensile armor layer 8 is 2-15 mm. It can be adjusted within the range of 7 mm, and the winding angle of the second tensile armor layer 8 can be adjusted within the range of 20~55 degrees; the third auxiliary layer 9 is non-adhesively wound on the outside of the second tensile armor layer 8, and the third auxiliary layer Layer 9 is made of any one of glass fiber tape, polyester tape and aramid tape, and this layer plays the role of binding the second tensile armor layer to prevent the second tensile armor layer from buckling or "bird "cage" fails, the width of the third auxiliary layer 9 can be adjusted within the range of 60-90 mm, the thickness of the third auxiliary layer 9 can be adjusted within the range of 0.3-1 mm, and the winding angle of the third auxiliary layer 9 can be adjusted within the range of 50-90 degrees Adjustable; the outer cladding layer 10 is coated on the outside of the third auxiliary layer 9 by extrusion molding non-bonding, and the outer cladding layer 10 is made of any one of medium-density polyethylene, high-density polyethylene and nylon. It can isolate the external seawater from the internal armor layer and prevent seawater from corroding the armor layer material.

A method for manufacturing a high-temperature resistant non-bonding flexible composite pipeline, the steps are as follows:

High temperature resistant non-bonded flexible composite pipelines are produced layer by layer from inside to outside;

Skeleton layer 1 is made of stainless steel strips, which are manufactured by locking machine pressing and interlocking forming;

The sacrificial layer 2 is made of polytetrafluoroethylene high temperature resistant tape. After the skeleton layer production process, the polytetrafluoroethylene high temperature resistant tape is spirally wound to the outside of the skeleton layer 1 by a high temperature tape winding machine;

The internal pressure sealing layer 3 is made of polyvinylidene fluoride pellets. After the sacrificial layer production process, the polyvinylidene fluoride pellets are melted by an extruder, and the polyvinylidene fluoride is coated on the outside of the sacrificial layer 2 through a mold;

The compression armor layer 4 is made of carbon steel strips, and after the production process of the internal pressure sealing layer, the carbon steel strips are alternately spirally wound to the outside of the internal pressure sealing layer 3 by a steel strip winding machine;

The first auxiliary layer 5 is made of plastic tape, and after the production process of the compressive armor layer, the plastic tape is spirally wound to the outside of the compressive armor layer 4 by a wrapping machine;

The first tensile armor layer 6 is made of flat steel strips, and after the production process of the first auxiliary layer, the flat steel strips are alternately helically wound to the outside of the first auxiliary layer 5 by a flat steel winding machine;

The second auxiliary layer 7 is made of a high-strength plastic tape of any one of glass fiber tape, polyester tape and aramid tape. A tensile armor layer 6 outside;

The second tensile armor layer 8 is made of flat steel strips, and after the production process of the second auxiliary layer, the flat steel strips are alternately helically wound to the outside of the second auxiliary layer 7 by a flat steel winding machine;

The third auxiliary layer 9 is made of a high-strength plastic tape of any one of glass fiber tape, polyester tape and aramid tape. After the production process of the second tensile armor layer, the high-strength plastic tape is spirally wound to the first The outer side of the secondary tensile armor layer 8;

The outer cladding layer 10 is made of high-molecular polymer material pellets of any one of medium-density polyethylene, high-density polyethylene and nylon. After the third auxiliary layer production process, the high-molecular polymer The pellets are melted, and the high molecular polymer is coated on the outside of the third auxiliary layer 9 through the mold.

The above descriptions are only examples of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the description of the present invention, or directly or indirectly used in other related technical fields, shall be The same reasoning is included in the patent protection scope of the present invention.

Claims (2)

1. The high-temperature-resistant non-bonding flexible composite pipeline is characterized by comprising a framework layer (1), a sacrificial layer (2), an internal pressure sealing layer (3), a compression-resistant armor layer (4), a first auxiliary layer (5), a first tensile armor layer (6), a second auxiliary layer (7), a second tensile armor layer (8), a third auxiliary layer (9) and an outer cladding layer (10);

the framework layer (1) is located at the innermost part of the pipeline, the framework layer (1) is made of S-shaped interlocking stainless steel bands, the width of the framework layer (1) is adjustable within the range of 20-60 mm, and the winding angle of the framework layer (1) is 90 degrees;

the sacrificial layer (2) is wound on the outer side of the framework layer (1) in a non-bonding mode, the sacrificial layer (2) is made of polytetrafluoroethylene high-temperature-resistant tape, the width of the sacrificial layer (2) is adjustable within the range of 50-90 mm, and the thickness of the sacrificial layer (2) is adjustable within the range of 0.4-2 mm;

the inner pressure sealing layer (3) is coated on the outer side of the sacrificial layer (2) in a non-bonding mode through extrusion molding, and the inner pressure sealing layer (3) is made of polyvinylidene fluoride;

the compression-resistant armor layer (4) is made of a carbon steel strip, the compression-resistant armor layer (4) is formed by spirally and non-adhesively winding the carbon steel strip on the outer side of the inner pressure sealing layer (3) in a forward and reverse alternating mode, the winding angle of the compression-resistant armor layer (4) is adjustable within the range of 80 to 90 degrees, the width of the compression-resistant armor layer (4) is adjustable within the range of 20 to 90 millimeters, and the thickness of the compression-resistant armor layer (4) is adjustable within the range of 0.5 to 1.5 millimeters;

the first auxiliary layer (5) is spirally and non-adhesively wound on the outer side of the pressure-resistant armor layer (4), the first auxiliary layer (5) is made of plastic tapes, the width of the first auxiliary layer (5) is adjustable within the range of 60-90 mm, the thickness of the first auxiliary layer (5) is adjustable within the range of 0.1-1 mm, and the winding angle of the first auxiliary layer (5) is adjustable within the range of 50-90 degrees;

the first tensile armor layer (6) is made of flat steel strips, the first tensile armor layer (6) is spirally and non-adhesively wound outside the first auxiliary layer (5) by the flat steel strips in a positive and negative alternating mode, the width of the first tensile armor layer (6) is adjustable within the range of 5-15 mm, the thickness of the first tensile armor layer (6) is adjustable within the range of 2~7 mm, and the winding angle of the first tensile armor layer (6) is adjustable within the range of 20-55 degrees;

the second auxiliary layer (7) is wound on the outer side of the first tensile armor layer (6) in a non-bonding mode, the second auxiliary layer (7) is made of any one of a glass fiber tape, a polyester tape and an aramid tape, the width of the second auxiliary layer (7) is adjustable within the range of 60-90 mm, the thickness of the second auxiliary layer (7) is adjustable within the range of 0.3-1 mm, and the winding angle of the second auxiliary layer (7) is adjustable within the range of 50-90 degrees;

the second tensile armor layer (8) is made of flat steel strips, the second tensile armor layer (8) is spirally and non-adhesively wound outside the second auxiliary layer (7) by the flat steel strips in a forward and reverse alternating mode, the width of the second tensile armor layer (8) is adjustable within the range of 5-15 mm, the thickness of the second tensile armor layer (8) is adjustable within the range of 2~7 mm, and the winding angle of the second tensile armor layer (8) is adjustable within the range of 20-55 degrees;

the third auxiliary layer (9) is wound on the outer side of the second tensile armor layer (8) in a non-bonding mode, the third auxiliary layer (9) is made of any one of a glass fiber tape, a polyester tape and an aramid tape, the width of the third auxiliary layer (9) is adjustable within the range of 60-90 mm, the thickness of the third auxiliary layer (9) is adjustable within the range of 0.3-1 mm, and the winding angle of the third auxiliary layer (9) is adjustable within the range of 50-90 degrees;

the outer coating layer (10) is coated on the outer side of the third auxiliary layer (9) in an extrusion molding non-bonding mode, and the outer coating layer (10) is made of any one of medium-density polyethylene, high-density polyethylene and nylon.

2. A method for manufacturing a high-temperature-resistant non-bonded flexible composite pipeline, which comprises the steps of claim 1: the manufacturing method of the high-temperature-resistant non-bonding flexible composite pipeline comprises the following steps:

step S1: producing the high-temperature-resistant non-bonded flexible composite pipeline layer by layer from inside to outside;

step S2: the framework layer (1) is made of stainless steel bands and is manufactured by profiling and interlocking of a locker;

and step S3: the sacrificial layer (2) is made of a polytetrafluoroethylene high-temperature resistant belt, and after the production process of the framework layer, the polytetrafluoroethylene high-temperature resistant belt is spirally wound to the outer side of the framework layer (1) through a high-temperature belt winding machine;

and step S4: the internal pressure sealing layer (3) is made of polyvinylidene fluoride granules, after the production process of the sacrificial layer, the polyvinylidene fluoride granules are melted through an extruding machine, and the polyvinylidene fluoride is coated to the outer side of the sacrificial layer (2) through a mould;

step S5: the pressure-resistant armor layer (4) is made of a carbon steel strip, and after the production process of the internal pressure sealing layer, the carbon steel strip is spirally wound to the outer side of the internal pressure sealing layer (3) in a positive and negative alternate mode through a steel strip winding machine;

step S6: the first auxiliary layer (5) is made of a plastic tape, and after the production process of the compression-resistant armor layer, the plastic tape is spirally wound to the outer side of the compression-resistant armor layer (4) through a winding machine;

step S7: the first tensile armor layer (6) is made of a flat steel strip, and after the first auxiliary layer production process, the flat steel strip is spirally wound to the outer side of the first auxiliary layer (5) in a positive and negative alternating mode through a flat steel winding machine;

step S8: the second auxiliary layer (7) is made of a high-strength plastic tape of any one of a glass fiber tape, a polyester tape and an aramid tape, and after the production process of the first tensile armor layer, the high-strength plastic tape is spirally wound to the outer side of the first tensile armor layer (6) through a winding machine;

step S9: the second tensile armor layer (8) is made of a flat steel strip, and after the production process of the second auxiliary layer, the flat steel strip is spirally wound to the outer side of the second auxiliary layer (7) in a positive and negative alternating mode through a flat steel winding machine;

step S10: the third auxiliary layer (9) is made of a high-strength plastic tape of any one of a glass fiber tape, a polyester tape and an aramid tape, and after the production process of the second tensile armor layer, the high-strength plastic tape is spirally wound to the outer side of the second tensile armor layer (8) through a winding machine;

step S11: the outer coating layer (10) is made of high polymer material granules of any one of medium-density polyethylene, high-density polyethylene and nylon, after the production process of the third auxiliary layer, the high polymer granules are melted through a plastic extruding machine, and the high polymer is coated to the outer side of the third auxiliary layer (9) through a die.

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