Stranded conductor and cable

Abstract

The invention discloses a stranded wire and a cable, and relates to the technical field of electric power facilities, the stranded wire comprises a core wire and a plurality of first molded wires, the radial cross section of the core wire is circular, the plurality of first molded wires with the radial cross section in a sector ring shape are stranded on the peripheral surface of the core wire, and the radius of the inner arc surface of each first molded wire is matched with the radius of the core wire; the gap between the first molded wires and the core wire is effectively filled, the sum of the arc center angles of the inner arc surfaces of the multiple first molded wires is smaller than 360 degrees, the problem of radial twisting increment of the twisted wire caused by mutual extrusion of the adjacent first molded wires in the twisting process is avoided, and the outer diameter of the twisted wire is reduced under the same current-carrying capacity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power facilities, in particular to a stranded conductor and cable. BACKGROUND

[0002] In the field of power transmission, power cables are usually made of multiple thin metal wires stranded to meet the requirements of electrical conductivity and mechanical strength.

[0003] In the manufacturing process of traditional stranded cables, the thin metal wires are generally designed in a circular cross-section. During the stranding process, a large gap is formed between adjacent wires, resulting in a low filling rate of the overall cable and an increased outer diameter. On the one hand, this increases the difficulty of transportation and storage, and on the other hand, due to the large gap between the wires, more space is occupied during laying or installation, which is not conducive to the design of compact power systems, and excessive gaps may cause uneven stress on the cable when bending or under pressure, affecting its mechanical stability and service life. SUMMARY

[0004] The purpose of the present application is to provide a stranded conductor and cable, which is stranded by a first type wire with a special shape and a core wire with a circular cross-section, and the sum of the central angles of the inner arcs of the multiple first type wires is less than 360°, thereby reducing the outer diameter of the cable while meeting the requirements of cable use.

[0005] To achieve the above-mentioned purpose, the present application provides the following solutions:

[0006] The present application provides a stranded conductor, comprising:

[0007] a core wire, the radial cross-section of the core wire being circular;

[0008] a first type wire, the first type wire being provided in multiple, the multiple first type wires being stranded on the outer peripheral surface of the core wire, the radial cross-section of the first type wire being fan ring-shaped, the radius of the inner arc of the first type wire matching the radius of the core wire, and the sum of the central angles of the inner arcs of the multiple first type wires being less than 360°.

[0009] As an embodiment, a second type wire is further included, the second type wire being provided in multiple, the multiple second type wires being stranded on the outer arc surface of the first type wire, the radial cross-section of the second type wire being fan ring-shaped, the inner arc surface of the second type wire matching the outer arc surface of the first type wire, the sum of the central angles of the inner arcs of the multiple second type wires being less than 360°, and the material of the first type wire being different from that of the second type wire.

[0010] As an embodiment, the material of the first type wire is aluminum alloy, and the material of the second type wire is copper.

[0011] As an embodiment, the first type line is provided with 5 wires, and the central angle of the inner arc surface of the first type line is 65-72°.

[0012] As an embodiment, the stranding pitch of the first type line is controlled between 165mm-185mm.

[0013] As an embodiment, the second type line is provided with 11 wires, and the central angle of the inner arc surface of the second type line is 30-32.7°.

[0014] As an embodiment, the stranding pitch of the second type line is controlled between 287mm-322mm.

[0015] As an embodiment, the outer surface of the first type line and / or the second type line is provided with a tin metal layer.

[0016] The application further provides a cable, which applies the above-mentioned stranded wire, and comprises at least three of the stranded wires, and the outer surface of the stranded wire is provided with an insulation layer.

[0017] As an embodiment, the cable comprises, from inside to outside, a tape layer, an inner lining layer, a braided armor layer and an outer sheath layer, and the tape layer is wrapped on the outside of the three stranded wires.

[0018] The application has the following technical effects relative to the prior art:

[0019] In the stranded wire disclosed by the application, the core wire with a circular radial section is used as a baseline, and the first type line with a fan ring-shaped radial section is used as a stranding wire, the radius of the inner arc surface of the first type line matches the radius of the core wire, the gap between the first type line and the core wire is effectively filled, the sum of the central angles of the inner arc surfaces of the multiple first type lines is less than 360°, that is, after the multiple first type lines are laid parallel to the outer surface of the core wire before stranding, there is a certain gap between the adjacent first type lines, the problem that the stranded wire produces a radial stranding increment due to mutual extrusion of the adjacent first type lines during stranding is avoided, and the outer diameter of the stranded wire is reduced under the same load flow. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort.

[0021] Fig. 1 It is a structural schematic diagram of the stranded wire in the embodiments of the application.

[0022] Fig. 2 The structure diagram of the cable in the embodiment of the present application is shown in the figure;

[0023] 1, core wire; 2, first type wire; 3, second type wire; 4, tape layer; 5, inner lining layer; 6, braided armor layer; 7, outer sheath layer; 8, PP filling rope; 9, insulation layer. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0025] The purpose of the present application is to provide a stranded conductor and a cable to solve the problems existing in the prior art, by radially cross-sectioning the first type wire into a fan ring shape and the core wire into a circular shape, and arranging the adjacent first type wires in a spaced-apart form, the technical effect of reducing the diameter of the stranded conductor is achieved.

[0026] In order to make the above-mentioned purposes, features and advantages of the present application more apparent and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0027] Please refer to Figs. 1-2 The stranded conductor disclosed in the embodiments of the present application comprises a core wire 1 and a first type wire 2. The radial cross-section of the core wire 1 is circular, and the radial cross-section of the first type wire 2 is fan ring-shaped. The radius of the inner arc surface of the first type wire 2 matches the radius of the core wire 1. The first type wire 2 is provided with a plurality of first type wires 2, which are stranded on the outer peripheral surface of the core wire 1. The sum of the arc center angles of the inner arc surfaces of the plurality of first type wires 2 is less than 360°. Since the radial cross-section of the first type wire 2 is fan ring-shaped, the first type wire 2 and the core wire 1, and the first type wire 2 and the first type wire 2 are more closely fitted, reducing the gap between the wires. At the same time, since the sum of the arc center angles of the inner arc surfaces of the plurality of first type wires 2 is less than 360°, when the first type wire 2 is parallelly spliced to the outer surface of the core wire 1 without being stranded, there is a certain gap between the adjacent first type wires 2. The existence of the gap can avoid the mutual extrusion of the adjacent first type wires 2 during the stranding process, thereby avoiding the problem of large radial increment of the first type wire 2 due to mutual extrusion. Therefore, under the condition that the sum of the radial cross-sectional areas of the core wire 1 and the first type wire 2 is unchanged, the outer diameter of the stranded conductor is reduced, i.e. under the same load current, the outer diameter of the stranded conductor is reduced, the floor space occupied by the stranded conductor is reduced, and the internal stress is optimized.

[0028] It can be understood that the radial direction herein refers to the direction perpendicular to the extension direction of the core wire 1 or the first type wire 2; and the fan ring shape is the shape obtained by cutting a ring along any two radial directions.

[0029] In this embodiment, the stranded wire further comprises a second type wire 3, the second type wire 3 is provided with a plurality of second type wires 3, the plurality of second type wires 3 are stranded on the outer arc surface of the first type wire 2, the radial cross section of the second type wire 3 is a fan ring shape, the inner arc surface of the second type wire 3 matches the outer arc surface of the first type wire 2, the sum of the arc center angles of the inner arc surfaces of the plurality of second type wires 3 is less than 360°, and the material of the first type wire 2 is different from that of the second type wire 3. Those skilled in the art can use two kinds of conductive metals with different weights, or two kinds of conductive metals with different conductive properties, or two kinds of conductive metals with different prices as the first type wire 2 and the second type wire 3 according to actual needs, so as to make stranded wires with the same weight but different wire properties or costs, stranded wires with the same conductive property but different weights or costs, and stranded wires with the same cost but different weights or conductive properties.

[0030] In this embodiment, the conductive metal includes but is not limited to silver, copper, aluminum, and aluminum alloy.

[0031] In this embodiment, the first type wire 2 and the second type wire 3 are stranded in opposite directions.

[0032] In this embodiment, the material of the first type wire 2 is aluminum alloy, and the material of the second type wire 3 is copper, forming an aluminum alloy core composite copper stranded wire. Compared with pure aluminum, aluminum alloy has good creep resistance, corrosion resistance and tensile strength, and copper has relatively better conductive performance. Using this manufacturing method, the stranded wire has high strength and stability while ensuring good conductive performance, and has strong use stability under the same load flow.

[0033] In this embodiment, the first type wire 2 is provided with 5 first type wires 2, the arc center angle of the inner arc surface of the first type wire 2 is 65°-72°, and the core wire 1 and the first type wire 2 are stranded to the right in a 1+5 manner to form a stranded wire.

[0034] Preferably, the arc center angle of the inner arc surface of the first type wire 2 is 71.3°.

[0035] In this embodiment, the diameter of the core wire 1 is 2.4 mm, and the thickness of the first type wire 2 along the radial direction is 1.65 mm.

[0036] Further, it can be understood that the first type wire 2 includes an outer arc surface, an inner arc surface and two side surfaces, the first type wire 2 is a symmetrical structure, one radius of the first type wire 2 can be used as the symmetry axis of the first type wire 2, and the farthest distance between the two side surfaces of the first type wire 2 is 3.25 mm and the closest distance is 1.4 mm in the direction perpendicular to the above symmetry axis.

[0037] In the embodiment, the stranding pitch of the first type wire 2 is controlled between 165mm and 185mm.

[0038] In the embodiment, the diameter of the sizing area of the stranding die is greater than the calculated outer diameter of the stranding wire, so that the stranding is performed in a way of slightly compacting the stranding, so that the stranding of the stranding wire is more compact. It can be understood that the sizing area refers to an area capable of controlling the diameter of the stranding wire, also referred to as a die, a forming port, etc.

[0039] In the embodiment, the stranding calculated outer diameter of the stranding wire stranding by the core wire 1 and the first type wire 2 is 5.6+3.05*2=11.7mm, and the sizing area of the stranding die adopts 11.5mm.

[0040] In the embodiment, the second type wire 3 is provided with 11, the central angle of the inner arc surface of the second type wire 3 is 30°-32.7°, and the second type wire 3 is stranding to the left on the outer arc surface of the first type wire 2 to form a stranding wire.

[0041] Preferably, the central angle of the inner arc surface of the second type wire 3 is 32.4°.

[0042] In the embodiment, the thickness of the second type wire 3 in the radial direction is 3.05mm.

[0043] Further, one radius of the second type wire 3 can be used as the symmetry axis of the second type wire 3, and the farthest distance between the two side surfaces of the second type wire 3 in the direction perpendicular to the symmetry axis is 3.2mm, and the closest distance is 1.56mm.

[0044] In the embodiment, the stranding pitch of the second type wire 3 is controlled between 287mm and 322mm.

[0045] In the embodiment, the stranding calculated outer diameter of the stranding wire stranding by the core wire 1, the first type wire 2 and the second type wire 3 is 5.6+3.05*2=11.7mm, and the sizing area of the stranding die adopts 11.5mm.

[0046] In the embodiment, the outer surface of the first type wire 2 and / or the second type wire 3 is provided with a tin metal layer, which avoids the electrochemical corrosion phenomenon caused by the direct contact between the aluminum alloy single wire and the copper single wire, and also solves the problem that the aluminum metal is easy to oxidize in the air, avoiding the safety hidden trouble.

[0047] In the embodiment, the first type wire 2 is a tin-plated aluminum alloy, and the second type wire 3 is a tin-plated copper.

[0048] In the embodiment, the core wire 1 is a tin-plated aluminum alloy.

[0049] In the embodiment, the stranded conductor is twisted by the core wire 1, the first type wire 2 and the second type wire 3, the core wire 1 is tinned aluminum alloy, the first type wire 2 is tinned aluminum alloy, and the second type wire 3 is tinned copper. The above stranded conductor data is obtained through repeated tests, and the direct current resistance at 20 DEG C is not more than 0.195 ohm / km, which meets the requirement of GB / T3956-2008 for tinned copper single wire stranded copper conductor.

[0050] The application further discloses a cable comprising at least three stranded conductors, and an insulation layer 9 arranged on the outer surface of the stranded conductors.

[0051] In the embodiment, the twisting direction of the three stranded conductors is opposite to the twisting direction of the second type wire 3, and specifically, the second type wire 3 is twisted to the left, and the stranded conductors are twisted to the right.

[0052] In the embodiment, the material of the insulation layer 9 is modified polypropylene, and the modified polypropylene insulation material is used to replace the cross-linked polyethylene insulation in the prior art. The polypropylene material is a thermoplastic material, and does not need to use a high-temperature cross-linking process, thereby reducing the production time and energy consumption. The polypropylene material can be completely recycled, thereby reducing the influence on the environment, and the waste material can be reused. The thermoplastic polypropylene insulated cable can better solve the environmental protection treatment after the product life ends, and simultaneously reduce the energy consumption in the product production process, and realizes green environmental protection.

[0053] Preferably, the 90 DEG C polypropylene insulation with a nominal thickness of 1.1 mm is arranged outside the stranded conductor in the form of extrusion.

[0054] In the embodiment, the cable comprises a tape wrapping layer 4, an inner lining layer 5, a braided armor layer 6 and an outer sheath layer 7 which are sequentially sleeved from inside to outside, and the tape wrapping layer 4 is wrapped on the outer side of the three stranded conductors.

[0055] In the embodiment, the tape wrapping layer 4 can preliminarily fix the three stranded conductors, so that the connection is more stable, and the tape wrapping layer 4 can be used as a mechanical protection layer to resist radial pressure and bending fatigue.

[0056] Preferably, the tape wrapping layer 4 is a halogen-free oxygen barrier tape.

[0057] In the embodiment, the inner lining layer 5 is produced in the form of extrusion to ensure the roundness of the cable. Preferably, the inner lining layer 5 is a low-smoke halogen-free polyolefin inner lining layer 5.

[0058] In the embodiment, the braided armor layer 6 is made of tinned copper with a nominal diameter of 0.30 mm, and the braiding density is not less than 80%. The braided armor layer 6 can further improve the tensile strength, compression resistance and torsional resistance of the cable, and the braided armor layer 6 forms electromagnetic shielding.

[0059] In this embodiment, the low-smoke halogen-free sheath material is used to extrude a 2.0 mm thick outer sheath. The outer sheath is produced by extrusion to ensure the roundness of the cable.

[0060] In this embodiment, the pitch ratio of the cable is controlled between 25-30 times.

[0061] Preferably, the voids between the stranded conductors are filled with a PP filling rope 8 to fill the cable core.

[0062] In this embodiment, the aluminum alloy is of grade 8030.

[0063] In this embodiment, the cable is used for power supply in a ship, which has a smaller weight, reducing the impact of the cable on the carrying capacity of the ship.

[0064] In this embodiment, the stranded conductor and the tinned copper single wire stranded copper conductor are compared, wherein the stranded conductor is an aluminum alloy core composite copper conductor, and the tinned copper single wire stranded copper conductor is composed of 19 2.49 mm tinned copper single wires stranded in 1+6+12 layers.

[0065] a. Outer diameter comparison:

[0066] The outer diameter of the aluminum alloy core composite copper conductor is 11.5 mm, and the outer diameter of the tinned copper single wire stranded copper conductor is 2.49*5=12.45 mm, and the outer diameter of the aluminum alloy core composite copper conductor is smaller.

[0067] b. Weight comparison:

[0068] The unit weight of the aluminum alloy core composite copper conductor is 5.6*5.6 / 4*3.14*2.703*0.99+

[0069] (11.5*11.5 / 4*3.14-5.6*5.6 / 4*3.14)*0.99*8.89=762.8 kg / km,

[0070] The theoretical calculation cross-sectional area of the tinned copper single wire stranded copper conductor is 2.49*2.49 / 4*3.14*19=92.5 mm 2 , the unit weight is 92.5*8.89=822.3 kg / km, and the unit weight of the aluminum alloy core composite copper conductor is smaller;

[0071] Take CJPF86 / SC, 0.6 / 1 kV, 3*95 mm 2 cable as an example:

[0072] Table 1 Size Comparison Table

[0073]

[0074] Table 2 Unit Weight Comparison Table

[0075]

[0076] As can be seen from Table 1 and Table 2, the marine power cable produced by using the stranded conductor disclosed in the application has a smaller outer diameter and a lighter weight compared with the traditional marine power cable.

[0077] The consumption of each raw material of the marine power cable produced by using the composite conductor of the present technology is lower than that of the traditional marine power cable, especially the consumption of copper, which is 2484.2+271.4=2755.6 kg / km for the traditional marine power cable and 2105.7+255.1=2360.8 kg / km for the marine power cable of the present technology, saving copper 2755.6-2360.8=394.8 kg / km, and if the price of copper is 70000 yuan / ton, the cost of pure copper consumption is 394.8*70 / 1000=27.636 yuan / m, so the economic value of the present technology is significant.

[0078] The principles and implementation manners of the present application are described by using specific examples in the present application, and the above examples are only used to help understand the method of the present application and its core idea; meanwhile, for those skilled in the art, the specific implementation manners and application ranges will be changed according to the idea of the present application. In conclusion, the content of the present specification should not be understood as a limitation of the present application.

Claims

1. A stranded wire, characterized in that, include: Core wire (1), the radial cross section of which is circular; The first type of wire (2) is provided with multiple first type of wires (2), which are twisted together on the outer circumferential surface of the core wire (1). The radial cross section of the first type of wire (2) is fan-shaped, and the radius of the inner arc surface of the first type of wire (2) matches the radius of the core wire (1). The sum of the arc center angles of the inner arc surfaces of the multiple first type of wires (2) is less than 360°.

2. The stranded conductor according to claim 1, characterized in that, It also includes a second type of line (3), which is provided with multiple second type of line (3). The multiple second type of line (3) are twisted together on the outer arc surface of the first type of line (2). The radial cross section of the second type of line (3) is fan-shaped. The inner arc surface of the second type of line (3) matches the outer arc surface of the first type of line (2). The sum of the arc center angles of the inner arc surfaces of the multiple second type of line (3) is less than 360°. The material of the first type of line (2) is different from the material of the second type of line (3).

3. The stranded conductor according to claim 2, characterized in that, The first profile (2) is made of aluminum alloy, and the second profile (3) is made of copper.

4. The stranded wire according to claim 2, characterized in that, The first profile (2) has 5 profiles, and the central arc angle of the inner arc surface of the first profile (2) is 65°-72°.

5. The stranded conductor according to claim 4, characterized in that, The twisting pitch of the first type of wire (2) is controlled between 165mm and 185mm.

6. The stranded conductor according to claim 2, characterized in that, The second profile (3) has 11 lines, and the central arc angle of the inner arc surface of the second profile (3) is 30°-32.7°.

7. The stranded conductor according to claim 6, characterized in that, The twisting pitch of the second type of wire (3) is controlled between 287mm and 322mm.

8. The stranded conductor according to claim 2, characterized in that, The outer surface of the first profile (2) and / or the second profile (3) is provided with a tin metal layer.

9. A cable, characterized in that, The stranded conductor according to any one of claims 1-7 comprises at least three stranded conductors, wherein the outer surface of the stranded conductors is provided with an insulating layer.

10. The cable according to claim 9, characterized in that, It includes a wrapping layer (4), an inner lining layer (5), a braided armor layer (6), and an outer sheath layer (7) arranged sequentially from the inside to the outside, with the wrapping layer (4) wrapping around the outside of the three stranded wires.

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