CN115346713A

CN115346713A - Marine light fire-resistant flexible data transmission shielding cable and preparation method thereof

Info

Publication number: CN115346713A
Application number: CN202210955970.1A
Authority: CN
Inventors: 李永江; 洪永飞; 杨佳昱; 任帅
Original assignee: Nanjing Quanxin Cable Technology Co Ltd
Current assignee: Nanjing Quanxin Cable Technology Co Ltd
Priority date: 2022-08-10
Filing date: 2022-08-10
Publication date: 2022-11-15

Abstract

The invention relates to the technical field of marine power cables, and particularly provides a marine light fire-resistant flexible data transmission shielding cable which comprises cable cores, wherein every two of the four cable cores are tangent and twisted with each other; the plurality of filling ropes are arranged among the four wire cores and are fixedly formed into cable cores with circular sections by the shielding layers together with the four cable cores; the outer sheath is extruded on the outer wall of the shielding layer; the shielding layer comprises a double-layer shielding layer formed by a lapping shielding layer lapped and wrapped on the outer wall of the cable core and a braided shielding layer wrapped on the outer wall of the lapping shielding layer, and a drainage wire is arranged between the braided shielding layer and the lapping shielding layer; the cable can simultaneously realize digital signal transmission and fire resistance on the basis of not changing the size of an insulating structure; the flexible twisted structure conductor is matched with double-layer composite insulation, so that the bending radius of a finished cable product is 4 times of the outer diameter of the cable, and the requirement of the minimum 10 times of the outer diameter of the cable specified by YD/T1019 is far less.

Description

Marine light fire-resistant flexible data transmission shielding cable and preparation method thereof

Technical Field

The invention relates to the technical field of marine power cables, in particular to a marine light fire-resistant flexible data transmission shielding cable and a preparation method thereof.

Background

With the development of shipbuilding and fire safety considerations, more and more special area cabling on ships are required to have fire-resistant characteristics, so that the ship fire-resistant data cable is required. The traditional cable is generally used for realizing fire resistance by wrapping mica tapes outside conductors, but because the signal transmission of the data cable is realized by an insulated wire pair, the transmission performance of the product can be influenced by wrapping the mica tapes on the conductors. Therefore, the existing fire-resistant data cable generally realizes fire resistance by arranging a plurality of fire-resistant layers, oxygen barriers, fire-resistant frameworks and the like outside the cable core or the line pair.

The fire-resistant data cables disclosed in patent documents with patent numbers CN202022770745.X, CN201921366603.8, CN201720545194.2, CN201520095000.4, CN201310370369.7 and CN201510070143.4 realize fire resistance by arranging a fire-resistant oxygen-insulating layer outside a cable body;

the technical scheme disclosed by the patent document with the patent number of CN201710863025.8 realizes fire resistance by arranging a fire-resistant material between the inside of the shielding aluminum plastic composite belt and the insulation on line;

the technical scheme disclosed in patent document CN201610363745.3 is that fire resistance is realized by arranging a foaming fire-resistant framework and arranging an oil-resistant layer, a fire-resistant fiber layer and a water-resistant layer outside a cable core.

However, the fire-resistant data cable has significant disadvantages, and the addition of the fire-resistant layer causes the problems of increased outer diameter, increased weight, increased hardness, increased bending radius and the like of the cable, so that the cable cannot meet the laying requirements of a ship in a narrow space.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a light fire-resistant flexible data transmission shielded cable for a ship, which comprises:

the cable cores are tangent to each other and are twisted with each other;

the wire core comprises a conductor, a filling layer and a wrapping tape, an insulating layer is extruded on the outer wall of the conductor to form an insulating conductor, the two insulating conductors are twisted in pairs to form a twisted pair, and the twisted pair and the filling layer distributed on the outer side of the twisted pair are fixed by the wrapping tape to form a circular section;

the plurality of filling ropes are arranged among the four wire cores and are fixedly formed into a cable core with a circular section together with the four wire cores by the shielding layer;

the outer sheath is extruded on the outer wall of the shielding layer;

the insulating layer is of a double-layer extrusion composite structure, the inner layer comprises a high-density polyethylene insulating layer, and the outer layer comprises a ceramic molding silicon rubber insulating layer;

the shielding layer comprises a double-layer shielding layer formed by a lapping shielding layer lapped on the outer wall of the cable core in an overlapping manner and a braided shielding layer coated on the outer wall of the lapping shielding layer, and a drainage wire is arranged between the lapping shielding layer and the braided shielding layer;

the wrapping shielding layer is formed by coating graphene, high-heat-conductivity metal and high-conductivity metal on a polyester film serving as a base material after chemical plating treatment to form a black conductive shielding belt;

the braided shielding layer comprises a tinned copper wire braided layer, and the included angle between the braided wires in the tinned copper wire braided layer and the axial direction of the cable is 45-60 degrees.

Preferably, the polyester film comprises a polyester fiber film, and the chemical components of the polyester fiber film comprise 60-65% of polyester fiber, 10-15% of carbon element, 5-10% of high-thermal-conductivity metal and 5-10% of high-electrical-conductivity metal.

Preferably, the thickness of the shielding tape is 41 +/-5 mu m, the tensile strength is not less than 6kg/mm < 2 >, and the plane resistance is not more than 0.1 omega.

Preferably, the lapping overlapping rate of the shielding tape is ≧ 20%, and the number of lapping layers is 2-3.

Preferably, the four wire cores are distributed in a rectangular shape, wherein the twisted pairs of the two wire cores on the diagonal are parallel to each other, and the twisted pairs of the two wire cores on the same side are perpendicular to each other.

Preferably, the high thermal conductivity metal and the high electrical conductivity metal include metallic copper, metallic nickel, and metallic silver.

Preferably, the diameter of the weaving wire in the tinned copper wire weaving layer is 0.1-0.15mm, and the weaving density of the tinned copper wire weaving layer is not less than 88%.

Preferably, the conductor is in a twisted structure formed by a regular twisting mode of 1+6+12, and the twisting pitch-diameter ratio is 8-12 times.

Preferably, the total thickness of the insulating layer is 0.8-1.5mm, and the thickness ratio of the inner layer to the outer layer is 1:1-1.

Preferably, the wrapping tape comprises a polyester tape, the wrapping covering rate of the polyester tape is 30-50%, and the number of wrapping layers is 2-3.

Preferably, the filling rope comprises a ceramic silicon rubber fire-resistant filling strip with a circular or prefabricated cross section.

Preferably, the plurality of filling ropes are divided into a first part and a second part, wherein the first part is positioned in a gap between the four wire cores, and the second part is positioned in a gap between the periphery of the four wire cores and the shielding layer.

Preferably, the outer sheath comprises a halogen-free flame retardant polyolefin sheath layer.

The invention provides another technical scheme, and a preparation method of a marine light fire-resistant flexible data transmission shielded cable comprises the following steps:

step 1, preparing a wire core, comprising the following steps:

step 1.1, preparing a conductor: the conductors are stranded by adopting tinned copper wires, the number of the conductors is 19, the wire diameter is 0.18mm, the conductors are arranged in a mode of 1 inner layer, 6 secondary outer layers and 12 outer layers, and the stranding pitch is 8-12 times of the outer diameter of the conductors;

step 1.2, preparing an insulated wire core: extruding an insulating layer on the outer side of the conductor stranded with the tinned copper wires by using an extruder, wherein the thickness of the insulating layer is 0.8-1.5mm;

step 1.3, preparing an insulated wire pair: twisting every two insulated wire cores to form an insulated wire pair, wherein four insulated wire pairs are formed, and the twisting pitch of each insulated wire pair is not more than 15mm;

step 1.4, filling hemp ropes on the outer sides of the insulated wire pairs, and simultaneously wrapping polyester tapes with a wrapping machine to fix the insulated wire pairs into a circular section, wherein the wrapping and covering rate of the polyester tapes is 30-50%;

step 2, preparing a cable core: arranging four wire cores in a pairwise tangent manner, filling gaps between every two adjacent wire cores with ceramic silicon rubber refractory filling strips, and meanwhile, wrapping a graphene shielding tape by using a wrapping machine, wherein the wrapping overlapping rate of the graphene shielding tape is not less than 20%;

step 3, preparing a shielding layer: weaving a tinned copper wire into a closed net cylinder on the outer side of the graphene shielding belt by using a weaving machine, and coating the net cylinder on the outer side of the graphene shielding belt to form the woven shielding layer, wherein the axial included angle between a woven wire of the tinned copper wire woven net cylinder and a cable is 45-60 degrees, and the weaving density of the tinned copper wire woven wire is not less than 88%;

step 4, preparing an outer sheath: extruding and wrapping halogen-free flame-retardant polyolefin outside the braided shielding layer by using an extruder to form an outer sheath;

the graphene shielding belt is formed by coating graphene, high-thermal-conductivity metal and high-electrical-conductivity metal on a polyester fiber film serving as a base material after chemical plating treatment.

Compared with the prior art, the marine light fire-resistant flexible data transmission shielded cable has the remarkable advantages that:

1. the cable simultaneously realizes digital signal transmission and fire resistance on the basis of not changing the size of an insulating structure;

2. the flexible twisted structure conductor is matched with double-layer composite insulation to ensure that the bending radius of a finished cable product is 4 times of the outer diameter of the cable and is far less than the minimum 10 times of the requirement of the outer diameter of the cable specified by YD/T1019;

3. the graphene shielding tape is lapped and the tinned copper wire is woven to form double-layer shielding, so that the data transmission cable is prevented from being influenced by strong current when the data transmission cable is applied in a narrow space of a ship, the electromagnetic interference is effectively reduced, and the reliability of the transmission performance is ensured;

4. the weight of the cable is reduced by about 15%, the outer diameter is reduced by 1-2 mm, the bending life is prolonged to more than 30000 times, and the production efficiency is improved by more than 20% compared with the existing fire-resistant data cable.

Drawings

The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing.

Fig. 1 is a view showing a light fire-resistant flexible data transmission shielded cable for a ship according to an embodiment of the present invention.

Fig. 2 is an axial view schematically showing a light fire-resistant flexible data transmission shielded cable for a ship according to an embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a wire core according to an embodiment of the present invention.

In the figure, 1, a wire core; 11. a conductor; 12. an insulating layer; 13. a filling layer; 14. wrapping a covering; 2. filling a rope; 3. a shielding layer; 31. wrapping a shielding layer; 32. weaving a shielding layer; 33. a drainage wire; 4. an outer sheath.

Detailed Description

In order to better understand the technical content of the present invention, specific embodiments are described below with reference to the accompanying drawings.

The invention discloses a light fire-resistant flexible data transmission shielded cable for ships, which aims to set an insulating layer extruded on the periphery of a conductor into a double-layer extrusion composite structure, wherein the inner layer adopts high-density polyethylene, the outer layer adopts ceramic-molded silicon rubber, and double-layer insulation is constructed by compounding the two layers of insulation, so that the transmission performance and the fire resistance of the cable are ensured on the basis of not changing the size of the insulation structure, the advantages of reducing the weight and the outer diameter of the cable, prolonging the bending life, improving the production capacity and the like of the cable are realized, and the cable meets the laying requirement of a ship in a narrow space.

The marine light fire-resistant flexible data transmission shielded cable according to the embodiment shown in fig. 1-3 comprises a core 1, a filling rope 2, a shielding layer 3 and an outer sheath 4.

Wherein, a plurality of sinle silk 1 are two-by-two tangent and intertwist each other. In the illustrated embodiment, 4 cores 1 are taken as an example for explanation.

The core 1 comprises a conductor 11, a filling layer 13 and a wrapping tape 14.

The conductor 11 is formed by twisting tinned copper wires, and the copper wires are low in resistivity, good in ductility, high in strength, anti-fatigue, good in stability, large in current-carrying capacity, good in oxidation resistance and corrosion resistance, and good in flexibility and mechanical strength. A twisting structure is formed by adopting a regular twisting mode of 1+6+12, and the twisting pitch-diameter ratio is 8-12 times, so that the resistance of the conductor 11 is ensured, the bending stress is reduced, and small-outer-diameter bending is realized.

Furthermore, the outer wall of the conductor 11 is extruded with an insulating layer 12 to form an insulated conductor.

The insulating layer 12 is of a double-layer extrusion composite structure, the inner layer comprises a high-density polyethylene insulating layer, the outer layer comprises a ceramic molding silicon rubber insulating layer, the total thickness is 0.8-1.5mm, the thickness ratio of the inner layer to the outer layer is 1:1-1.2, and the total thickness meets the specification of YD/T1019-2013 polyolefin insulating horizontal twisted pair cable for digital communication.

Specifically, the high-density polyethylene material of the inner layer has excellent electrical properties but does not have fire resistance; the outer ceramic molding silicon rubber material is a novel high-molecular refractory material, has excellent characteristics of fire prevention, flame retardance, low smoke, no toxicity and the like, residues after combustion are hard ceramic shells, the ceramic shells are calcined by high-temperature flame to generate silicon dioxide hard ceramics which can resist the temperature of not lower than 1100 ℃, flame is isolated and blocked to continue to burn, the hard shells are not melted and do not drip in a fire environment, and the firm protection effect is achieved in the condition of fire, so that the ceramic shell is widely applied to an insulating layer of a high-voltage refractory cable, the density of the ceramic shell is (1.24 +/-0.02) g/cm < 3 >, the dielectric loss tangent value is 0.006 +/-0.002, the relative dielectric constant is 3.2 +/-0.05, the relative dielectric constant is larger, the ceramic shell is mainly used for the insulating layer of the high-voltage refractory cable, the insulating layer which is independently used as a high-frequency data transmission cable can influence the transmission performance, and the ceramic shell cannot be independently used as the insulating layer.

In the embodiment, the high-density polyethylene material and the ceramic molding silicon rubber material are compounded to construct double-layer insulation, so that the equivalent relative dielectric constant is 2.72 +/-0.05, the dielectric loss tangent value is 0.0034 +/-0.002, the equivalent dielectric constant is reduced, the insulation loss is reduced, and the cable has the transmission performance and the fire resistance on the basis of not changing the thickness and the size of an insulation structure.

Furthermore, the two insulated conductors are twisted to form a twisted pair, and are fixed together with the filling layer 13 distributed on the outer side by the wrapping tape 14 to form a circular cross section.

In combination with the drawings, in a specific embodiment, the four wire cores 1 are distributed in a rectangular shape, wherein the twisted pairs of the two wire cores 1 on the diagonal are parallel to each other, and the twisted pairs of the two wire cores 1 on the same side are perpendicular to each other, so that the cable is more flexible and easy to bend.

The filling layer 13 is made of hemp ropes and filled in the outer sides and gaps of the twisted pairs, so that the cross section of the twisted pairs is more round when the twisted pairs are wrapped by the wrapping tape 14.

The wrapping tape 14 comprises a polyester tape, the wrapping overlapping rate of the polyester tape is 30-50%, the number of wrapping layers is 2-3, and the wrapping tape is mainly used for fixing the cable core 1, so that the cable core 1 is more round and neat integrally.

Furthermore, a plurality of filling ropes 2 are arranged among the four wire cores 1 and are fixedly formed into a cable core with a circular section together with the four cable cores 1 by the shielding layer 3.

It is specific, the packing rope 2 includes that the cross-section is circular or the fire-resistant packing strip of pottery silicon rubber of prefabricated shape, many fire-resistant packing strips of pottery silicon rubber divide into first portion and second part, wherein, first portion is located in the clearance in the middle of four sinle silks 1, the second part is located the periphery of four sinle silks 1 and the clearance between 3 on the shielding layer, not only can play the filling effect, make the cross-section of cable core more round, and can play fire-resistant effect when the conflagration takes place, receive the high temperature burning to be ablated into the inside sinle silk 1 of ceramic hard shell further separation flame burning cable, extension cable conductor's circular telegram time.

In this embodiment, the shielding layer 3 comprises a double-layer shielding layer by overlapping the wrapping shielding layer 31 wrapped on the outer wall of the cable core and the braided shielding layer 32 wrapped on the outer wall of the wrapping shielding layer 31, and the braided shielding layer 32 and the wrapping shielding layer 31 are provided with a drainage wire 33 for shielding grounding.

Specifically, the wrapping shielding layer 31 includes a graphene shielding tape, the wrapping overlapping rate of the graphene shielding tape is not less than 20%, the number of wrapping layers is 2-3, and the thickness of the graphene shielding tape is (41 ± 5) μm. In optional embodiment, the shielding area is 2 layers around the package number of piles, and the first layer left side is around the package, and the second floor right side is around the package, and it is 50% to take the lid percentage around the package, and like this, the shielding area double-deck is overlapped and is reversely around the package at the outer wall of filling rope 2, makes the cross-section after the cable stranding more round.

The graphene shielding belt is formed by taking a polyester fiber film as a base material, coating graphene, high-heat-conductivity metal and high-conductivity metal after chemical plating treatment to form a black conductive shielding belt, in a specific embodiment, the high-heat-conductivity metal and the high-conductivity metal are prepared by mixing metal copper, metal nickel and metal silver powder, and the graphene shielding belt is coated on the surface of the polyester fiber film base material after chemical plating treatment, has the characteristics of electric conduction, heat conduction, softness, toughness, low smoke, zero halogen, environmental protection and high and low temperature resistance, is suitable for shielding and isolating electromagnetic signal interference during cable high-frequency signal transmission, and also has the effect of efficient heat conduction.

Further, in the chemical components of the shielding tape in the embodiment, the polyester fiber is 60% to 65%, the carbon element is 10% to 15%, the high thermal conductivity metal is 5% to 10%, and the high electrical conductivity metal is 5% to 10%.

In an alternative embodiment, the thickness of the shielding tape is (41 ± 5) μm. The shielding belt formed by the chemical components has the tensile strength of not less than 6kg/mm < 2 >, and the plane resistance of not more than 0.1 omega; through the impact cycle test at the temperature of between 40 ℃ below zero and 120 ℃, the shielding tape strip does not have the defects of color change, pulverization, corrosion, dyeing, peeling and the like, is still intact after 20 ten thousand times of high-strength swinging, can ensure the reliability and stability of the transmission performance of the cable when applied to a cable wrapping shielding layer, and prolongs the bending life of the cable.

Further, weave shielding layer 32 including the tinned copper wire weaving layer, adopt the tinned copper wire to weave the net formation, the cladding is at the outer wall around package shielding layer 31, constitutes double-deck shielding layer with around package weaving layer 31 together, mainly plays electromagnetic shield's effect, avoids outside electromagnetic signal to influence inner conductor 11's signal transmission.

Wherein the angle between the knitting wire of the tinned copper wire knitting layer and the axial direction of the cable is 45-60 degrees, and the knitting density of the tinned copper wire knitting wire is not less than 88 percent; in an alternative embodiment, the diameter of the braided filaments is 0.12mm, the number of the spindles is 32, the number of the spindles is 8, and the pitch is not more than 95mm.

In this embodiment, adopt graphite alkene shielding tape to overlap to weave around package and tinned copper wire and constitute double-deck shielding layer, the lining that outer shielding (tinned copper wire was woven) can be regarded as to the inlayer shielding (graphite alkene shielding tape), and the braided wire joint stabbing of tinned copper wire braided mesh when avoiding whole cable bending is insulating, and outer shielding tinned copper wire braided mesh has good mechanical properties, can provide the mechanical protection when the cable is crooked.

The double-layer shielding can avoid the influence of strong electricity on the cable in the application of a narrow and small space of a ship during data transmission, the shielding efficiency reaches 60dB (far higher than the 40dB shielding efficiency requirement of the existing ship cable), the electromagnetic interference is effectively reduced, and the reliability of the transmission performance of the cable is ensured.

As shown in fig. 1 and 2, in order to reduce the outer diameter of the cable, only one outer sheath 4 is provided in this embodiment, and is wrapped around the outer wall of the braided shield 32 to reduce the outer diameter of the finished product.

Preferably, the outer sheath 4 is made of halogen-free flame-retardant polyolefin, has excellent flame-retardant performance, low smoke and low toxicity, overcomes the defect that a large amount of smoke generated during the combustion of the traditional halogen-containing polymer can suffocate people and corrode instruments and equipment, and accords with IEC60092-360:2021 the specification of SHF1 or SHF2 meets the environmental trend of green shipbuilding.

step 1, preparing a wire core 1, comprising the following steps:

1-1), preparing a conductor 11: the conductors 11 are twisted by adopting tinned copper wires, the number of the conductors is 19, the wire diameter is 0.18mm, the arrangement mode is that 1 inner layer, 6 secondary outer layers and 12 outer layers are arranged, and the twisting pitch is 10 times of the outer diameter of the conductors 11, so that the resistance of the conductors is ensured, the bending stress is reduced, small-outer-diameter bending is realized, the flexibility is high, and the cable laying is convenient;

1-2) preparing an insulated wire core: an extruder is adopted to extrude an insulating layer 12 outside a conductor 11 twisted by tinned copper wires, the insulating layer 12 adopts a double-layer co-extrusion extruder to extrude a double-layer composite structure, the inner layer adopts high-density polyethylene, the outer layer adopts ceramic-molded silicon rubber, the thickness ratio of the inner layer to the outer layer is 1.2, the total thickness of the insulating layer 12 is 1.5mm, the inner layer adopts a high-density polyethylene material, the electric performance is excellent, the insulating layer is coated on the outer wall of the conductor 11 and has good electric insulating property and safety, the outer layer adopts a ceramic-molded silicon rubber material which has a large relative dielectric constant and can not be independently used as an insulating layer of a high-frequency data transmission cable, the transmission performance can be influenced, but the insulating layer has the characteristics of excellent fire resistance, flame retardance, low smoke, no toxicity and the like, the residues after combustion are hard ceramic shells, the insulating layer can not melt and drip in a fire environment and can be coated on the outer wall of the high-density polyethylene insulating layer, and the firm and smooth protection effect can be ensured in power transmission under the fire condition;

in the embodiment, the high-density polyethylene material and the ceramic molding silicon rubber material are compounded to construct double-layer insulation, so that the cable has transmission performance and fire resistance on the basis of not changing the thickness and size of an insulation structure;

1-3), preparing an insulated wire pair: each two insulated wire cores are twisted and combined with one insulated wire pair, and four insulated wire pairs are formed, wherein the twisting pitch of each insulated wire pair is 10mm, so that the flexibility is realized to the maximum extent on the basis of ensuring that the direct-current resistance of the conductor is qualified, and the cable is convenient to bend in a narrow and small manner when being fixedly laid;

1-4) filling hemp ropes outside the insulated wire pairs, and simultaneously adopting a wrapping machine to wrap a polyester tape around the package to fixedly form a wire core 1 with a circular cross section, wherein the first layer of polyester tape is wrapped leftwards, the second layer of polyester tape is wrapped rightwards, and the wrapping and covering rate of the two layers of polyester tapes is 50%, so that the tightness of the internal structure of the wire core 1 can be ensured.

Step 2, preparing a cable core: the four wire cores 1 are arranged in a pairwise tangent mode, gaps are filled between every two adjacent wire cores 1 with ceramic silicon rubber fireproof filling strips, meanwhile, a wrapping machine is adopted to wrap graphene shielding belts to fixedly form cable cores with circular cross sections, the graphene shielding belts on the first layer are wrapped in the left direction, the graphene shielding belts on the second layer are wrapped in the right direction, and the wrapping overlapping rate of the graphene shielding belts on the two layers is 50%.

Step 3, preparing a shielding layer 3: the shielding layer 3 is a double-layer shielding layer, the inner layer is a wrapping shielding layer 31 formed by wrapping the graphene shielding tape in the step 2, the outer layer is a braided shielding layer 32 formed by braiding a tinned copper wire on the outer side of the graphene shielding tape by using a braiding machine in a weaving manner, the braided shielding layer 32 is coated on the outer side of the graphene shielding tape 31 and forms a double-layer shielding together with the wrapping shielding layer 31 formed by wrapping the graphene shielding tape 31;

the inner graphene shielding belt is made of a polyester fiber film as a base material, graphene is coated after chemical plating treatment, high-heat-conductivity metal and high-conductivity metal are coated, a black conductive belt material is formed, the inner graphene shielding belt can replace a traditional winding belt to wind the outer sides of the wire core 1 and the filling rope 2, a cable core is fixedly formed to be circular in cross section and arranged on the outer side of the outer braided shielding layer 32 and can also be used as a lining layer of outer shielding (braided by tinned copper wires), insulation is prevented from being stabbed by braided wire joints of a tinned copper wire braided net when the whole cable is bent, the inner graphene shielding belt has good electric conduction, heat conduction, softness, toughness, low smoke, zero halogen, environmental protection and high and low temperature resistance, electromagnetic signal interference and heat conduction are shielded and isolated when the whole cable is suitable for high-frequency signal transmission, the polyester fiber, the carbon element is 13%, the high-heat-conductivity metal is 6%, and the high-conductivity metal is 7% in the chemical composition, and the inner graphene shielding belt is applied to the cable winding shielding layer, so that the reliability and the stability of the cable winding transmission performance can be ensured, and the bending life of the cable is prolonged.

Furthermore, the included angle between the weaving wire of the outer tinned copper wire weaving net and the axial direction of the cable is 55 degrees, the weaving density of the tinned copper wire weaving wire is 90 percent, the woven tinned copper weaving net has good mechanical performance, mechanical protection when the cable is bent can be provided, double-layer shielding formed by rebuilding the inner graphene shielding belt and the outer tinned copper wire weaving net is adopted, the influence of strong current on the cable in the application of a narrow space of a ship during data transmission can be avoided, and the transmission stability of the cable is ensured.

Step 4, preparing an outer sheath 4: the extruder is utilized to extrude and wrap the halogen-free flame retardant polyolefin outside the braided shielding layer 32 to form an outer sheath, and in order to reduce the outer diameter of the finished cable, only one outer sheath is arranged.

Specifically, the sheath is extruded and is adopted the extruding machine, screw rod draw ratio 23, and extrusion compression ratio is 1.15, and the aircraft nose is equipped with deep runner flow divider, through crowded tubular mould package, and the die sleeve size is the same with the cable external diameter or slightly littleer, and the line length of holding is 2.5mm, and the die core die sleeve adopts two cone moulds, and stretch ratio is no more than 1.5, and the material runner of mould should be as gentle as possible to make mould core and die sleeve fully separate.

Furthermore, the temperature of each zone of the extruder during extrusion is controlled to be 155 ℃ in the 1 zone, 175 ℃ in the 2 zone, 185 ℃ in the 3 zone, 185 ℃ in the 4 zone, 190 ℃ in the 5 zone, 200 ℃ in the head and 200 ℃ in the die respectively.

Although the invention has been described with reference to preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention should be determined by the appended claims.

Claims

1. A marine light fire-resistant flexible data transmission shielded cable, comprising:

the cable comprises cable cores (1), wherein the cable cores (1) are tangent pairwise and are twisted with each other;

the cable core (1) comprises a conductor (11), a filling layer (13) and a wrapping tape (14), wherein an insulating layer (12) is extruded on the outer wall of the conductor (11) to form an insulating conductor, two insulating conductors are twisted in pairs to form a twisted-pair, and the twisted-pair and the filling layer (13) distributed on the outer side of the insulating conductor are fixed by the wrapping tape (14) to form a circular section;

the plurality of filling ropes (2) are arranged among the four wire cores (1) and are fixedly formed into a cable core with a circular section by the shielding layer (3) together with the four wire cores (1);

the outer sheath (4) is extruded on the outer wall of the shielding layer (3);

the insulating layer (12) is of a double-layer extrusion composite structure, the inner layer comprises a high-density polyethylene insulating layer, and the outer layer comprises a ceramic forming silicon rubber insulating layer;

the shielding layer (3) is a double-layer shielding layer formed by a wrapping shielding layer (31) which is overlapped on the outer wall of the cable core and a braided shielding layer (32) which is coated on the outer wall of the wrapping shielding layer (31), and a drainage wire (33) is arranged between the wrapping shielding layer (31) and the braided shielding layer (32);

the wrapping shielding layer (31) is formed by coating graphene, high-heat-conductivity metal and high-conductivity metal on a polyester fiber film serving as a base material after chemical plating treatment to form a black conductive shielding tape.

2. The marine light fire-resistant flexible data transmission shielded cable according to claim 1, wherein the shielding tape comprises 60% to 65% of polyester fiber, 10% to 15% of carbon, 5% to 10% of high thermal conductivity metal, and 5% to 10% of high electrical conductivity metal.

3. The marine light-duty fire-resistant flexible data transmission shielded cable according to claim 1, wherein the thickness of the shielding tape is 41 ± 5 μm, and the tensile strength is not less than 6kg/mm ² The plane resistance is less than or equal to 0.1 omega.

4. The marine light-weight fire-resistant flexible data transmission shielding cable according to claim 1, wherein the lapping overlapping rate of the shielding tape is ≧ 20%, and the number of lapping layers is 2-3.

5. The marine light-duty fire-resistant flexible data transmission shielded cable of claim 1, characterized in that said braided shield (32) comprises a tinned copper braid, the braid filaments of said tinned copper braid being angled at 45 ° to 60 ° to the cable axis.

6. The marine light-weight fire-resistant flexible data transmission shielded cable of claim 1, wherein the diameter of the braid of the tinned copper wire braid is 0.1-0.15mm, and the braiding density of the tinned copper wire braid is ≧ 88%.

7. The marine light-duty fire-resistant flexible data transmission shielded cable of claim 1, characterized in that said conductor (11) is formed into a twisted structure in a regular twisting manner of 1+6+12, and the twist pitch ratio is 8-12 times.

8. The marine light fire-resistant flexible data transmission shielded cable according to any one of claims 1 to 7, wherein four of the wire cores (1) are arranged in a rectangular shape, wherein the twisted pair of the two wire cores (1) located at diagonal lines are parallel to each other, and the twisted pair of the two wire cores (1) located at the same side edge are perpendicular to each other.

9. The marine light fire-resistant flexible data transmission shielded cable according to claim 1, wherein the wrapping tape (14) comprises polyester tape, the wrapping coverage of the polyester tape is 30-50%, and the number of wrapping layers is 2-3.

10. Marine light-weight fire-resistant flexible data transmission shielded cable according to claim 1, characterized in that the filler rope (2) comprises a ceramic silicone rubber fire-resistant filler strip having a circular or prefabricated shape in cross-section.

11. Marine light-weight fire-resistant flexible data transmission shielded cable according to claim 1, characterized in that the outer sheath (4) comprises a halogen-free flame-retardant polyolefin sheath layer.

12. The method for preparing a marine light fire-resistant flexible data transmission shielded cable according to any one of claims 1 to 11, comprising the steps of:

step 1, preparing a wire core (1), comprising the following steps:

step 1.1, preparing a conductor (11): the conductors (11) are stranded by adopting tinned copper wires, the number of the conductors is 19, the wire diameter is 0.18mm, the conductors are arranged in an arrangement mode of 1 inner layer, 6 secondary outer layers and 12 outer layers, and the stranding pitch is 8-12 times of the outer diameter of each conductor (11);

step 1.2, preparing an insulated wire core: extruding an insulating layer (12) on the outer side of the conductor (11) stranded with the tinned copper wires by using an extruder, wherein the thickness of the insulating layer (12) is 0.8-1.5mm;

step 1.3, preparing an insulated wire pair: twisting every two insulated wire cores to form an insulated wire pair, wherein the total number of the insulated wire pairs is four, and the twisting pitch of each insulated wire pair is not more than 15mm;

step 1.4, filling hemp ropes at the outer sides of the insulated wire pairs, and simultaneously wrapping polyester tapes by a wrapping machine to fix the insulated wire pairs into a circular section, wherein the wrapping and covering rate of the polyester tapes is 30-50%;

step 2, preparing a cable core: arranging four wire cores (1) in a pairwise tangent mode, filling gaps between every two adjacent wire cores (1) with ceramic silicon rubber fire-resistant filling strips, and meanwhile, wrapping a graphene shielding tape by using a wrapping machine, wherein the wrapping overlapping rate of the graphene shielding tape is not less than 20%;

step 3, preparing a shielding layer (3): weaving a tinned copper wire into a closed mesh cylinder on the outer side of the graphene shielding belt by using a weaving machine, and coating the closed mesh cylinder on the outer side of the graphene shielding belt to form the woven shielding layer (32), wherein the angle between the weaving wire of the tinned copper wire woven mesh cylinder and the axial direction of the cable is 45-60 degrees, and the weaving density of the tinned copper wire woven wire is not less than 88%;

step 4, preparing an outer sheath (4): extruding halogen-free flame-retardant polyolefin outside the braided shielding layer (32) by using an extruder to form an outer sheath;