CN115431575A

CN115431575A - Continuously-produced narrow-band structure fiber reinforced plastic composite pipe and manufacturing method thereof

Info

Publication number: CN115431575A
Application number: CN202211056612.3A
Authority: CN
Inventors: 孔德彬; 孙之状; 汤毅; 倪奉尧; 胡召元; 王国利
Original assignee: Shandong Donghong Pipe Industry Co Ltd
Current assignee: Shandong Donghong Pipe Industry Co Ltd
Priority date: 2022-08-30
Filing date: 2022-08-30
Publication date: 2022-12-06

Abstract

The invention belongs to the technical field of fiber reinforced composite pipelines, and provides a fiber reinforced plastic composite pipe with a continuous production narrow-band structure and a manufacturing method thereof, wherein the manufacturing method comprises the following steps: performing combined co-extrusion on the multi-type functional materials to prepare a multi-layer co-extrusion structure; cooling and forming the multilayer co-extrusion structure, preheating, and winding the narrow-band prepreg reinforced fibers and the core pipe at an angle of 54.7-60 degrees to form a composite structure, wherein two adjacent narrow-band prepreg reinforced fiber layers are bonded by hot melting; and after the fiber reinforced layer is compounded, extruding the outer layer structure of the pipe by using an extruder, cooling, cutting and sealing to obtain the composite pipe. The invention adopts narrow bands, realizes continuous production without shutdown, reduces production cost and improves efficiency at the same time. The winding machine is a special winding machine. The narrow-band structure can adopt multilayer compounding before being put into production, so that the total investment of equipment is reduced, and the additional energy consumption of heating and winding machine operation caused by the overall investment is reduced.

Description

Continuously-produced narrow-band structure fiber reinforced plastic composite pipe and manufacturing method thereof

Technical Field

The invention belongs to the technical field of fiber reinforced composite pipelines, and particularly relates to a narrow-band structure fiber reinforced plastic composite pipe and a manufacturing method thereof capable of realizing continuous production.

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

The existing fiber reinforced plastic composite pipeline structure mainly comprises a wide fiber band and (silk) linear fibers which are presoaked, and the two product structures are different from the aspects of implementation modes and product performance.

Composite pipes with pre-impregnated broad fiber tapes as reinforcement often have the following disadvantages: 1. the equipment investment is large, the equipment is complex, and the one-time investment is high. 2. Because the manufacturing equipment limits the pipeline production continuity and is limited by the length of the single-disk fiber belt and the overall design of the equipment, the single-disk fiber belt needs to be stopped and replaced after being consumed, and long-time continuous production cannot be realized. 3. The production cost is high, the efficiency is low, the starting and stopping frequency of the pipeline is increased because the pipeline cannot realize long-time continuous production, the production cost of the pipeline is increased, and the production efficiency is influenced. But it has advantages in terms of product quality: 1. the pressure-bearing is stable: because the inner fiber surface of the adopted fiber belt-shaped structure is completely pre-soaked, under the condition of bearing the same pipeline circumferential stress, the contact area of the fiber and the pre-soaked resin material (mainly polyolefin) is large, the pipeline structure is more stable when the composite pipeline bears pressure, the problem of pressure bearing capacity attenuation does not exist after long-term use, and the composite structure among fibers is good. 2. The application range is wide: the contact area between the fiber material and the pre-impregnated resin material is large, so that the problem of shear failure of fiber reinforcement or other reinforced structures and pre-impregnated resin caused by pipeline pressure bearing at high temperature is solved, the temperature resistance of the composite pipeline can be improved, the composite pipeline is suitable for conveying media with the temperature of more than 40 ℃, and the composite pipeline has better performance in conveying oil, halogen, hot spring water, high-temperature water and the like.

The composite pipe taking the pre-impregnated (silk) linear fiber as the reinforcement has the following advantages: 1. the pipe can realize continuous production, the single preimpregnated (silk) linear fiber can be manually supplemented to realize continuous production after consumption is finished, and the pipe has high production efficiency and low cost. 2. The overall input of the pipe production line is lower than that of a ribbon fiber reinforced pipeline. However, such pipes also have the following disadvantages: 1. the stability of the pressure-bearing structure is poor: because the surfaces of the preimpregnated (silk) linear fibers are mostly preimpregnated on the surfaces of the fasciculate fibers, the insides of the fasciculate fibers are not in direct contact with the preimpregnated materials, but the whole fasciculate fibers are used as a design basis when the pipeline pressure bearing is calculated, the phenomenon that the pipeline bursting pressure cannot reach the bursting pressure before the pipeline pressure bearing after the pipeline is subjected to long-term pressure bearing often occurs, the problem of long-term pressure-resistant attenuation exists, and the performance of the composite structure problem of the pipeline is poor particularly when the pipeline is subjected to high temperature. 2. The production process needs filling materials: because the pipeline fiber reinforced layer is in a (silk) thread shape, gaps exist after the reinforced layer is wound, and in order to ensure the structural integrity of the pipeline, an extruder is required to be added to extrude materials (resin or modified bonding resin) to fill the gaps, so that the stability of the overall structure of the pipeline can be ensured.

Disclosure of Invention

In order to solve the problems, the invention provides a narrow-band structure fiber reinforced plastic composite pipe capable of being continuously produced and a manufacturing method thereof. According to the structural design of an integral product, the pipe adopts the continuous production steps of a production line, and is divided into main process routes of core pipe extrusion, core pipe cooling forming, reinforced fiber winding, outer layer extrusion compounding, cooling, cutting and sealing according to the integral production process route.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect of the present invention, there is provided a method for manufacturing a fiber reinforced plastic composite pipe with a continuously producible narrow-band structure, comprising:

performing combined co-extrusion on the multi-type functional materials to prepare a multi-layer co-extrusion structure;

cooling and forming the multilayer co-extrusion structure, preheating, and winding the narrow-band prepreg reinforced fibers and the core pipe pipeline at 54.7-60 degrees to form a composite structure, wherein two adjacent narrow-band prepreg reinforced fiber layers are bonded by hot melting;

and after the fiber reinforced layer is compounded, extruding the outer layer structure of the pipe by using an extruder, cooling, cutting and sealing to obtain the composite pipe.

In a second aspect of the invention, a narrow-band structure fiber reinforced plastic composite pipe manufactured by the method is provided.

In a third aspect of the present invention, the above-mentioned narrow-band fiber reinforced plastic composite pipe is provided, which can satisfy conventional fluid transportation, in pipelines with temperature requirements, such as: the oil transportation, the brine transportation, the hot spring water transportation and the high-temperature water transportation also have good application prospects.

The invention has the advantages of

(1) The invention provides a fiber reinforced plastic composite pipe with a narrow-band structure and a manufacturing method thereof, which can be continuously produced, and provides a new idea and a new method for a fiber reinforced composite pipeline.

(2) The invention mainly provides a novel structure of a fiber reinforced composite pipeline and a processing method thereof, wherein the type of fibers before presoaking can be selected in various ways.

(3) The composite pipeline core tube material can be adjusted according to the use working condition and functional requirements, and the application condition and the field of products are expanded.

(4) The invention adopts the narrow-band structure, which not only maintains the reinforcing effect of the wide-band structure, but also avoids the pipeline pressure-bearing defect that the fiber material of the line (silk) -shaped structure is not completely impregnated.

(5) The invention adopts the narrow-band structure to facilitate the operation and the replacement, realizes the continuous production of the ribbon-shaped fiber reinforced composite pipe with excellent performance, reduces the production cost and improves the production efficiency of the pipeline.

(6) The narrow-band structure can adopt multilayer compounding before being put into production, so that the design and processing compounding times of subsequent products are reduced, and the equipment input and processing cost are reduced.

(7) The narrow-band structure hot-melt combination can realize the continuity of the fiber layer in the production process of the reinforced fiber layer, so that the fiber bearing continuity of the pipeline is maintained in the process of replacing and using the fiber reinforced layer, and the pressure bearing effect of the pipeline is ensured.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention, and together with the description, serve to explain the invention and not to limit the invention.

FIG. 1 is a block diagram of several primary reinforcing fibers;

fig. 2 is a schematic structural diagram of a fiber reinforced plastic composite pipe with a narrow-band structure, wherein the structure comprises 1, a core pipe, 2, a narrow-band prepreg reinforced fiber layer and 3, an outer layer.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

A narrow-band structure fiber reinforced plastic composite pipe and a manufacturing method thereof capable of realizing continuous production are disclosed, wherein the pipe adopts production line continuous production steps according to the structural design of an integral product, and is divided into main process routes of core pipe extrusion, core pipe cooling forming, reinforced fiber winding, outer layer extrusion compounding, cooling, cutting and sealing according to the integral production process route.

In some embodiments, the core tube extrusion is a traditional process, the material extruded by the core tube is mainly polyolefin, and the material of the core tube can be extruded and processed by materials such as polybutylene, polyethylene (including crosslinked polyethylene and heat-resistant polyethylene), polypropylene and the like according to different use conditions and fields. Meanwhile, the core pipe is manufactured into a multi-layer co-extrusion structure according to the functional requirements of customers, and functional pipe types such as wear resistance, antibiosis, crack growth resistance and the like are manufactured.

In some embodiments, the core tube extrusion is cooled and sized by a vacuum box, and a cooling water tank can be added according to different extrusion output and thickness of the pipe to accelerate the cooling of the pipe.

In some embodiments, after the core tube is pulled by the tractor, the core tube passes through the wind ring to remove residual moisture from the pipe and clean the surface of the pipe. The core tube is preheated, and the main purpose is to provide composite heat support for reinforcing the narrow-band structure fibers and compounding the core tube, so that interlayer compounding is facilitated.

In some embodiments, narrow tape prepreg reinforcing fibers are wound in a disk shape and mounted onto a dedicated winder shaft. The production speed of the special winding machine is matched with that of the core tube, so that the winding angle of the narrow-band prepreg reinforced fiber and the pipeline is 54.7-60 degrees, the special winding machine is designed in an even number, every two special winding machines are one reinforcing unit, and the winding direction of one reinforcing unit is opposite. The number of the reinforcing units is related to the required model pressure and the used material of the pipe, and multi-unit compounding can be adopted. The whole surface of the pipe body has no gap in the winding process of the narrow-band-shaped reinforced fiber material.

In some embodiments, the narrow-band reinforcing fiber material may be a fiber type selected from glass fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, polyester fiber, carbon fiber, and the like, and the fiber material is pre-impregnated with polyolefin resin, and the type of pre-impregnated resin material is generally the same as the core tube material.

In some embodiments, the thickness of the single layer of the narrow-band-shaped preimpregnation reinforcing fiber is generally 0.15-0.6mm according to different fiber types, the width of the narrow band is selected from 5-30mm according to different product designs, and the design of different types and pressure pipes is determined according to the design tensile strength, the thickness, the width and the number of the narrow-band-shaped preimpregnation reinforcing fiber. Meanwhile, the narrow-band prepreg reinforced fiber layer can realize multi-layer compounding before production, the number of winding total layers in the production process can be reduced by directly using the narrow-band prepreg reinforced fiber layer after multi-layer compounding, the design defect that the higher thickness cannot be realized due to the prepreg reinforced fiber layer is overcome, and the equipment investment and the production cost are reduced. The original thick structure can not be achieved before production, and the fiber layer can be used after being compounded, so that the compounding times of the fiber layer on production equipment are reduced, and meanwhile, the investment of a special winding machine unit of the equipment is reduced.

In some embodiments, each disk of narrow tape-shaped prepreg reinforcing fiber layers has a relatively small size due to light weight, and the single disk can be conveniently installed on a winder shaft to be replaced in the production process production line operation process without stopping the machine. In addition, before the consumption of the single-disc narrow-band-shaped preimpregnated reinforced fiber layer is completed, the disc tail can be taken out to be thermally fused with a new disc head, so that the continuous production of the pipeline is realized, the hot-melt joint belongs to a hot-melt overlapping structure, the overlapping length is determined according to the maximum length of the used reinforced fiber so as to ensure the bearing continuity of the reinforcement, and the weak point of the bearing of the pipe is avoided. The prepreg reinforced fiber layer can be replaced without stopping when the production line runs and the consumed reinforced layer is replaced, meanwhile, the prepreg reinforced fiber layer can be welded by adopting special welding equipment to ensure the production continuity, and the welding overlapping length is determined according to the maximum length of the used reinforced fiber to ensure that the problem of pressure-bearing weak points caused by fiber discontinuity does not exist in the pipe.

In some embodiments, after winding of each narrow strip-shaped prepreg reinforcing fiber layer is completed, the surface is heated, the heating temperature and the heating time are determined according to the softening and melting temperature of the used materials, so that the surface of the prepreg narrow strip is melted, the prepreg narrow strip is well compounded with the previous process, and the integrity of the reinforcing layer is ensured.

In some embodiments, according to the product design, after the compounding of each unit of the fiber reinforced layer is completed according to the product design, the outer layer structure of the pipe is extruded through a lateral extruder, and after the outer layer of the pipe is shaped through a vacuum box and a cooling water tank, the length is fixed or the pipe is coiled and cut.

In some embodiments, after the pipeline is produced, the end face of the pipe is sealed to avoid the problem of failure of the pipe under pressure.

The present invention is described in further detail below with reference to specific examples, which are intended to be illustrative of the invention and not limiting.

Example 1

Taking dn160 × 3.5MPa core tube and outer layer made of high density polyethylene resin for PE100 grade pipeline as an example, and glass fiber as a reinforcing material, the product is mainly applied to municipal water conservancy water supply engineering, and the product is manufactured and designed as follows:

1. the raw material requirements are as follows:

polyethylene resin: PE100 grade pipeline grade high-density polyethylene resin is adopted.

Parameters of the narrow-band structure fiber reinforced layer: the width is 10mm, the thickness is 0.4mm, the glass fiber content is 60%, the average tensile strength is 900MPa (700 MPa is adopted for calculation), and HDPE pre-dipping treatment is adopted.

(layer number of the glass fiber tape is required to be calculated and confirmed according to the type of the pipe)

2. The product structure design:

core tube: the non-functional layer is integrally made of PE100 grade pipeline-grade high-density polyethylene resin. (the layer can adjust the material expansion field according to the functional requirements), and the design thickness of the core tube is 4.1mm.

Enhancement layer: the narrow-band structure compounding is adopted, the calculation requirement needs to reach 2.1mm, namely 6 layers of structures are needed to meet the design requirement, certain melting thickness reduction exists, 2.1mm is designed, if 3 winding unit sides (namely 3 units wound left and right and 6 layers of structures) are needed to realize pipe production according to a conventional method, 2 winding units can be adopted for replacing (namely 1 winding unit adopts 0.8mm pre-impregnated narrow-band production through pre-compounding, and the other winding unit adopts 0.4mm pre-impregnated narrow-band which is not compounded as 1 winding unit narrow-band production) to achieve the same effect.

Outer layer design: the whole body is made of PE100 grade pipeline grade high-density polyethylene resin, and the design thickness of the outer layer is 2.9mm.

3. The effect is achieved:

(1) and the narrow band is adopted, continuous non-stop production is realized, the production cost is reduced, and the efficiency is improved. The winding machine is a special winding machine.

(2) The pre-impregnated narrow belt needs 6 layers of structures and 3 winding units according to the original design, and can be replaced by a 4-layer structure form of 2 winding units, so that the total investment of equipment is reduced, and the additional energy consumption of heating and winding machine operation caused by the total investment is reduced.

(3) Important product properties:

compressive cracking stability: pipeline compression of 50% without cracking and delaminating

The burst pressure of the pipe is as follows: the pipe bursting pressure is 13.1MPa at the temperature of 20 ℃.

Hydrostatic test of the pipe: 1.2PN at 60 ℃ and 165h, and the pipeline is not damaged and leaked.

60 ℃,1.1PN,1000h, and no damage or leakage of the pipeline.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a fiber reinforced plastic composite pipe with a continuously producible narrow-band structure is characterized by comprising the following steps:

2. The method for manufacturing a fiber reinforced plastic composite pipe with a continuously producible narrow-band structure according to claim 1, wherein the material extruded from the core pipe is mainly polyolefin, and is selected based on different use conditions and fields.

3. The method for manufacturing a fiber reinforced plastic composite pipe with a continuously producible narrow band structure according to claim 1, wherein the fiber type of the narrow band-shaped reinforcing fiber material is at least one of glass fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, polyester fiber, and carbon fiber.

4. The method for manufacturing a continuously producible fiber reinforced plastic composite pipe with a narrow tape structure according to claim 1, wherein the thickness of the single layer of the narrow tape prepreg reinforcing fiber is between 0.15 and 0.6mm, and the width of the narrow tape is between 5 and 30 mm.

5. The method for manufacturing a fiber reinforced plastic composite pipe with a continuously producible narrow band structure according to claim 1, wherein different models and pressure pipe designs are determined by calculation according to the design tensile strength, thickness, width and number of the narrow band-shaped prepreg reinforced fibers.

6. The method for producing a continuously producible narrow band structure fiber reinforced plastic composite pipe according to claim 1, wherein the narrow band prepreg reinforcing fiber layers are subjected to multilayer compounding before production, and the narrow band prepreg reinforcing fiber layers subjected to multilayer compounding are directly used.

7. The method for producing a fiber-reinforced plastic composite pipe with a narrow tape structure capable of being continuously produced according to claim 1, wherein the prepreg reinforcing fiber layer is replaced without stopping the production line while replacing the consumed reinforcing layer, and the prepreg reinforcing fiber layer is welded to ensure the production continuity.

8. A method of manufacturing a continuously producible narrow band structural fiber reinforced plastic composite pipe according to claim 1, wherein the weld overlap length is determined according to the maximum length of the reinforcing fibers used to ensure that the pipe is free of pressure weak points due to fiber discontinuities.

9. A narrow-band structural fiber-reinforced plastic composite pipe manufactured by the method of any one of claims 1 to 8.

10. Use of the narrow band structural fiber reinforced plastic composite pipe of claim 9 in fluid transport, comprising: oil transportation, brine transportation, hot spring water transportation and high-temperature water transportation.