CN112821300A - Hollow cable sheath pipe wound by continuous fiber prepreg tape - Google Patents
Hollow cable sheath pipe wound by continuous fiber prepreg tape Download PDFInfo
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- CN112821300A CN112821300A CN202011579942.1A CN202011579942A CN112821300A CN 112821300 A CN112821300 A CN 112821300A CN 202011579942 A CN202011579942 A CN 202011579942A CN 112821300 A CN112821300 A CN 112821300A
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- pipe
- layer
- prepreg tape
- plastic pipe
- continuous fiber
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G3/00—Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
- H02G3/02—Details
- H02G3/04—Protective tubing or conduits, e.g. cable ladders or cable troughs
- H02G3/0462—Tubings, i.e. having a closed section
- H02G3/0481—Tubings, i.e. having a closed section with a circular cross-section
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G3/00—Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
- H02G3/02—Details
- H02G3/06—Joints for connecting lengths of protective tubing or channels, to each other or to casings, e.g. to distribution boxes; Ensuring electrical continuity in the joint
Abstract
The invention discloses a hollow cable sheath pipe wound by a continuous fiber prepreg tape, which comprises an inner-layer plastic pipe, an outer-layer pipe, trapezoidal support ribs, arc trapezoidal hollow holes and an electric melting connector, wherein the trapezoidal support ribs are equidistantly distributed between the inner-layer plastic pipe and the outer-layer pipe, and the arc trapezoidal hollow holes are positioned between the adjacent trapezoidal support ribs; the trapezoidal support ribs, the inner layer plastic pipe and the outer layer pipe are fused into a whole under the action of isomorphous structure molecular bonds. The continuous fiber prepreg tape wound hollow cable sheath pipe has the advantages of high strength, high corrosion resistance, high stability and long service life.
Description
Technical Field
The invention relates to the field of continuous fiber prepreg tape reinforced composite pipes, in particular to a hollow cable sheath pipe wound by a continuous fiber prepreg tape.
Background
The continuous fiber prepreg tape reinforced composite pipe has the advantages of high strength, thin wall, light weight, corrosion resistance, long service life and the like, and is widely applied to oil field technical pipe networks, industrial and chemical pipe networks, oil and gas long-distance pipeline networks, municipal water supply and heat supply pipe networks, cable sheath pipes and the like.
In the manufacturing process of the composite pipe, the continuous fiber prepreg tape is additionally arranged in general to bear the hoop and axial stress of the pipeline, the high tensile mechanical property of the prepreg tape is fully utilized to achieve the purpose of saving plastic materials, and the economy of the manufactured pipeline is realized so as to improve the competitiveness and the added value of products.
In general, the continuous fiber prepreg tape reinforced composite pipe is manufactured by adopting a three-layer structure of a plastic inner layer, a prepreg tape middle layer and a plastic surface layer, the manufacturing process of the structure is simple, the material composition is single, and the structure is used by a large number of pipeline manufacturing enterprises. A pipe-line system for cable sheathing pipe, its pipeline is inside not bearing pressure and belongs to non-bearing pipeline, the very important technical indicator of this pipeline just can bear outside high pressure both high ring rigidity and prevent that the pipeline from excessively bearing and warping, cause pre-buried pipeline can't pass through the circular cable of laying, consequently, should satisfy the bearing requirement in the many cable high loads of multilayer overlapping sleeve pipe built-in cable as cable sheathing pipe high rigidity's mechanical properties, so this pipeline needs to use high strength's continuous fibers preimpregnation area, realize as the outer reinforcing material of pipeline that the tubular product of preparation increases rigidity, the reinforcing, then satisfy the operation requirement in cable sheathing pipe high rigidity. The pipe joint is used for the cable sleeve, the inside of the cable sleeve is not communicated with flowing media but is internally provided with solid matters, so that the fiber exposed out of the pipe fitting interface can meet the use requirement of the cable sleeve without being technically sealed, and after the pipeline system interface is sealed by fusion welding, external muddy water can be prevented from entering the pipeline to meet the use requirement, so that in a pipeline system with a large-opening pipe ditch for laying the cable sleeve, the pipeline joint adopts a fusion welding sealing form as a pipeline interface to meet the use requirement. The cable sheath pipe is laid in a non-excavation traction crossing method, a pipeline interface needs to be sealed to prevent muddy water from entering the inner wall of a pipeline, and meanwhile the pipeline interface needs to meet the requirement of the interface strength in a long-distance pipeline crossing process by meeting the pipeline traction force, so that in a pipeline system using the non-excavation traction cable sheath pipe, the pipe joint adopts a sleeve pipe joint and pipe port integral hot melting welding mode to meet the use requirement of a high-strength interface.
In order to increase the rigidity of the protecting pipe body, the protecting pipe manufactured by the solid wall generally adopts the method of improving the total wall thickness of the pipe body to improve the section inertia moment of the pipe body so as to improve the ring rigidity of the pipe body; or the elastic modulus of the material for manufacturing the pipe body is improved, so that the ring stiffness of the pipe body is improved.
Chinese patent 201911353582.0 discloses a continuous fiber prepreg tape reinforced cable sheath, which comprises a plastic inner layer and a continuous fiber prepreg tape reinforced combination layer, wherein the continuous fiber prepreg tape reinforced combination layer comprises a transition layer, a reinforced stiffening layer and a cladding surface layer, and the transition layer is clad on the outer wall of the plastic inner layer and is fused with the plastic inner layer to form a whole. The two continuous fiber prepreg tape reinforced cable sheath pipes are connected together through a rubber sealing pipe joint or an electric smelting pipe joint, two ends of the rubber sealing pipe joint are respectively sleeved on the continuous fiber prepreg tape reinforced cable sheath pipes, a concave rubber sealing ring is sleeved at a position which is in contact with the continuous fiber prepreg tape reinforced cable sheath pipes, two ends of the electric smelting pipe joint are sleeved on the ends of the continuous fiber prepreg tape reinforced cable sheath pipes, and a plurality of resistance wires are arranged on the inner wall of the electric smelting pipe joint. The port of the rubber closed pipe joint is arranged at the groove of the concave rubber sealing ring, so that external muddy water can be prevented from entering the pipeline, the muddy water prevention effect is good, and the connection strength is high. In addition, although this protecting pipe includes inlayer plastic tubing and continuous fibers preimpregnation area reinforcing combined layer, the produced huge axial tensile stress problem of non-excavation traction process is not solved in this technical pipeline application, and non-hollow solid wall pipe can not reach natural draft rapid cooling's effect, produces many multiple cables and piles up self heat-generating body accumulative heating problem, seriously influences the life of built-in cable outsourcing insulator, leads to cable life's reduction then.
Disclosure of Invention
The invention aims to provide a hollow cable sheath pipe wound by a continuous fiber prepreg tape, which solves the problems that the strain of a high axial tensile pipeline of a non-excavation traction pipe is applied, the accumulated temperature of a cable is reduced by cable heat storage, and the service life is to be prolonged.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention relates to a hollow cable sheath pipe wound by a continuous fiber prepreg tape, which comprises an inner-layer plastic pipe, an outer-layer pipe, trapezoidal support ribs, circular-arc trapezoidal hollow holes and solid-wall plastic pipe connectors; the trapezoid supporting ribs are distributed between the inner-layer plastic pipe and the outer-layer pipe at equal intervals, and the arc trapezoid hollow holes are positioned between the adjacent trapezoid supporting ribs; the trapezoidal support ribs, the inner-layer plastic pipe and the outer-layer pipe are fused into a whole under the action of isomorphous structure molecular bonds; the electric smelting connector both can be used for connecting inlayer plastic tubing also can connect outer pipe and form confined butt fusion mouth, prevents that outside earth from getting into circular arc trapezoidal hollow hole and protecting pipe.
Furthermore, the outer layer pipe is firstly overlapped on the outer wall of the trapezoidal support rib in a multi-layer mode through a unidirectional prepreg tape with a forward winding angle (pipe shaft) of 15-30 degrees to form a first stirrup ring layer, then the unidirectional prepreg tape with a reverse winding angle (pipe shaft) of 15-30 degrees is overlapped in a multi-layer mode, wound and stuck on the outer wall of the first stirrup ring layer to form a second stirrup ring layer, and the first stirrup ring layer and the second stirrup ring layer jointly form a high-axial-tensile-resistance stress layer.
Further, 70-90% of polypropylene material and 30-10% of talcum powder are compounded to form the gear-shaped melt at the high temperature of 160-230 ℃ under the cooperation of an extruder and a circular sawtooth-shaped die, and the gear-shaped melt is subjected to vacuum spray cooling and shaping by a built-in sizing sleeve to form the high-modulus inner-layer plastic pipe and the trapezoid supporting ribs.
Furthermore, the trapezoid supporting ribs adopt an isosceles trapezoid structure; the upper bottom of the isosceles trapezoid structure is fused with the inner layer plastic pipe, and the lower bottom of the isosceles trapezoid structure is fused with the outer layer plastic pipe.
Compared with the prior art, the invention has the beneficial technical effects that:
the continuous fiber prepreg tape is wound on the trapezoidal support ribs of the hollow cable sheath pipe, the inner-layer plastic pipe and the outer-layer pipe and fused into a whole through the action of isomorphous structure molecular bonds, so that the structural stability of the sheath pipe is improved, and the cost of raw materials is saved; the trapezoidal support ribs adopt an isosceles trapezoid structure, so that the combination fastness of the protective sleeve and the stability of a structural body as well as the radial and axial tensile strength and shear strength of the pipe body are greatly improved; the inner layer plastic pipe adopts a high-modulus inner layer plastic pipe, the strength is improved by more than 60% compared with that of a common plastic material, and then the elastic modulus and the ring stiffness performance of the composite pipe body are improved; the bidirectional prepreg tape tube improves the structural strength of the tape surface layer, and further ensures that the sheath tube surface layer material can bear external impact and cannot crack and break; the arc trapezoid hollow holes form a large air circulation channel in the body of the protective sleeve, so that heat generated by the cable can be rapidly extracted out of the protective sleeve, the insulating sleeve of the external cable is prevented from being influenced by temperature, and the service life of the cable is prolonged; the same inner plastic pipe and the same outer plastic pipe are connected together by the electric melting connector, so that the pipe end is sealed, muddy water is prevented from entering the pipe, and the requirements of traction and dragging of a trenchless laying pipeline can be met. In a word, the continuous fiber prepreg tape winding hollow cable sheath pipe has the advantages of high strength, high corrosion resistance, high stability, long service life and wide application.
Drawings
The invention is further illustrated in the following description with reference to the drawings.
FIG. 1 is a cross-sectional view of a continuous fiber prepreg tape wrapped around a hollow cable sheath according to the present invention;
FIG. 2 is a connection structure diagram of the electrofusion connector and the inner plastic pipe;
FIG. 3 is a drawing showing the connection structure of the electrofusion couplings and the outer pipes;
FIG. 4 is a view showing the structure of an outer tube;
FIG. 5 is a view showing the structure of a circular saw-tooth-shaped mold;
description of reference numerals: 1. an inner plastic pipe; 1-1, trapezoidal support ribs; 2. an outer tube; 2-1, a first stirrup ring layer; 2-2, a stirrup ring layer II; 3. circular arc trapezoid hollow holes; 4. an electric melting connector.
Detailed Description
As shown in fig. 1, the hollow cable sheath pipe wound with the continuous fiber prepreg tape comprises an inner plastic pipe 1, an outer pipe 2, trapezoidal support ribs 1-1, circular-arc trapezoidal hollow holes 3 and electric melting connectors 4, wherein the trapezoidal support ribs 1-1 are equidistantly distributed between the inner plastic pipe 1 and the outer pipe 2. The arc trapezoid hollow holes 3 are located between the adjacent trapezoid support ribs 1-1, and one of the purposes is to achieve the effects of ventilating and cooling, dredging the heat in the sheath tube and preventing the built-in cable from heating, and the other purpose is to save more than 30% of raw materials by arranging the arc trapezoid hollow holes, and also to improve the rigidity of the cable sheath tube body so as to meet the use requirements of high-strength and large-span support.
The trapezoidal support ribs 1-1, the inner plastic pipe 1 and the outer pipe 2 are fused into a whole under the action of isomorphous molecular bonds, so that the stability of a three-layer structure to the maximum extent is realized, and then the effect of high external force impact load bearing capacity of the protective sleeve is realized.
As shown in fig. 4, the outer layer pipe 2 is firstly formed by multilayer superposition of the unidirectional prepreg tape of the forward 15-30-degree winding angle pipe shaft on the outer wall of the trapezoidal support rib 1-1 to form a first hoop layer 2-1, and then formed by multilayer superposition of the unidirectional prepreg tape of the reverse 15-30-degree winding angle pipe shaft on the outer wall of the first hoop layer 2-1 to form a second hoop layer 2-2, and the first hoop layer 2-1 and the second hoop layer 2-2 jointly form a high axial tension resistance stress layer, so that the purpose that the manufactured cable sheath pipe can be used for a non-excavation traction pipe and the effect of high axial tension resistance are achieved.
The inner-layer plastic pipe 1 and the trapezoidal support ribs 1-1 are prepared by compounding 70-90% of polypropylene material and 30-10% of talcum powder at the high temperature of 160-230 ℃, extruding and molding a gear-shaped melt under the cooperation of an extruder and a circular sawtooth-shaped die (shown in figure 5), and carrying out vacuum spray cooling and shaping on the gear-shaped melt by a built-in sizing sleeve to prepare the high-modulus inner-layer plastic pipe 1 and the trapezoidal support ribs 1-1. The high-rigidity high-heat-resistance sheath pipe has the characteristics of high bending modulus more than 1800MPa and Vicat softening point more than 157 ℃, so that the sheath pipe has the characteristics of high rigidity and high heat deformation temperature, and further meets the use requirements of high buried depth and high heat resistance of the sheath pipe. The inner plastic pipe 1 is designed into a long through type arc trapezoid hollow hole pipe, the space thickness of the inner pipe body is greatly increased, the inertia moment value of the pipe body is further improved, and on the basis of saving 30% of raw materials, the ring stiffness of the pipe body is further improved to 24-40 kN/m2。
The trapezoid supporting ribs 1-1 are of isosceles trapezoid structures, the inner inclination angle alpha of the isosceles trapezoid structures is 30-45 degrees, the upper bottoms of the isosceles trapezoid structures are fused with the inner-layer plastic pipe 1, and the lower bottoms of the isosceles trapezoid structures are fused with the outer-layer pipe 2, so that the area of the trapezoid supporting ribs 1-1 can be increased, more contact surfaces with the outer-layer pipe 2 are achieved, and the combination fastness and the stability of a structure body are improved; on the other hand, the outer layer tube 2 is fused and the compressive strength effect of the outer layer tube is improved.
Electric smelting connector 4 is used for connecting inlayer plastic tubing 1, outer pipe 2 form confined butt fusion mouth, prevent that outside earth from getting into circular arc trapezoidal hollow hole 3 and protective casing, satisfy the requirement that the pipeline was drawn and is dragged is laid in the non-excavation. The structure diagram of the fusion of the electrofusion connector 4 and the inner plastic pipe 1 is shown in fig. 2, and the outer peripheries of the outer pipe 2 and the capacitance connector 4 are ensured to be on the same horizontal plane. The structure of the fusion with the outer tube 2 is shown in fig. 3, which ensures the tightness of the connection.
The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.
Claims (4)
1. A hollow cable protective sleeve wound by a continuous fiber prepreg tape comprises an inner plastic pipe (1), an outer pipe (2), a trapezoidal support rib (1-1), an arc trapezoidal hollow hole (3) and a solid wall plastic pipe connector (4); the method is characterized in that: the trapezoid supporting ribs (1-1) are distributed between the inner layer plastic pipe (1) and the outer layer pipe (2) at equal intervals, and the arc trapezoid hollow holes (3) are positioned between the adjacent trapezoid supporting ribs (1-1); the trapezoidal support ribs (1-1), the inner plastic pipe (1) and the outer plastic pipe (2) are fused into a whole through the action of isomorphous structure molecular bonds; electric smelting connector (4) both can be used for connecting inlayer plastic tubing (1), also can connect outer pipe (2) and form confined butt fusion mouth, prevent that outside earth from getting into circular arc trapezoidal hollow hole (3) and protective sheath pipe.
2. The continuous fiber prepreg tape wound hollow cable sheath tubing of claim 1, wherein: the outer layer pipe (2) is firstly overlapped on the outer wall of the trapezoid support rib (1-1) in a multi-layer mode through a forward 15-30-degree winding angle (pipe shaft) unidirectional prepreg tape to form a first stirrup ring layer (2-1), then the reverse 15-30-degree winding angle (pipe shaft) unidirectional prepreg tape is overlapped, wound and welded on the outer wall of the first stirrup ring layer (2-1) in a multi-layer mode to form a second stirrup ring layer (2-2), and the first stirrup ring layer (2-1) and the second stirrup ring layer (2-2) jointly form a high axial tensile stress resistance layer.
3. The continuous fiber prepreg tape wound hollow cable sheath tubing of claim 1, wherein: the inner-layer plastic pipe (1) and the trapezoidal support ribs (1-1) are prepared by compounding 70-90% of polypropylene material and 30-10% of talcum powder at the high temperature of 160-230 ℃, extruding a gear-shaped melt under the cooperation of an extruder and a circular sawtooth-shaped die, and carrying out vacuum spray cooling and shaping on the gear-shaped melt by a built-in sizing sleeve to prepare the high-modulus inner-layer plastic pipe (1) and the trapezoidal support ribs (1-1).
4. The continuous fiber prepreg tape wound hollow cable sheath tubing of claim 1, wherein: the trapezoid supporting ribs (1-1) adopt isosceles trapezoid structures; the upper bottom of the isosceles trapezoid structure is fused with the inner layer plastic pipe (1), and the lower bottom of the isosceles trapezoid structure is fused with the outer layer plastic pipe (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011579942.1A CN112821300A (en) | 2020-12-28 | 2020-12-28 | Hollow cable sheath pipe wound by continuous fiber prepreg tape |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011579942.1A CN112821300A (en) | 2020-12-28 | 2020-12-28 | Hollow cable sheath pipe wound by continuous fiber prepreg tape |
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| Publication Number | Publication Date |
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| CN112821300A true CN112821300A (en) | 2021-05-18 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011579942.1A Pending CN112821300A (en) | 2020-12-28 | 2020-12-28 | Hollow cable sheath pipe wound by continuous fiber prepreg tape |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202360912U (en) * | 2011-11-22 | 2012-08-01 | 浙江伟星新型建材股份有限公司 | Reinforced composite tube wound by continuous fiber preimpregnation belts |
| CN203571242U (en) * | 2013-12-05 | 2014-04-30 | 浙江经纬集团环保工程有限公司 | Bilaterally-wound reinforced anti-cracking plastic structure wall pipe |
| CN107588286A (en) * | 2016-07-07 | 2018-01-16 | 林世平 | Hollow wall continuous fiber prepreg tape winding pipe |
| CN110932203A (en) * | 2019-12-25 | 2020-03-27 | 上海英泰塑胶股份有限公司 | Continuous fiber prepreg tape reinforced cable sheath pipe |
| CN111425672A (en) * | 2020-04-08 | 2020-07-17 | 上海英泰塑胶股份有限公司 | Heat-preservation integrated continuous fiber prepreg tape reinforced composite pipe and processing method |
-
2020
- 2020-12-28 CN CN202011579942.1A patent/CN112821300A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202360912U (en) * | 2011-11-22 | 2012-08-01 | 浙江伟星新型建材股份有限公司 | Reinforced composite tube wound by continuous fiber preimpregnation belts |
| CN203571242U (en) * | 2013-12-05 | 2014-04-30 | 浙江经纬集团环保工程有限公司 | Bilaterally-wound reinforced anti-cracking plastic structure wall pipe |
| CN107588286A (en) * | 2016-07-07 | 2018-01-16 | 林世平 | Hollow wall continuous fiber prepreg tape winding pipe |
| CN110932203A (en) * | 2019-12-25 | 2020-03-27 | 上海英泰塑胶股份有限公司 | Continuous fiber prepreg tape reinforced cable sheath pipe |
| CN111425672A (en) * | 2020-04-08 | 2020-07-17 | 上海英泰塑胶股份有限公司 | Heat-preservation integrated continuous fiber prepreg tape reinforced composite pipe and processing method |
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Application publication date: 20210518 |