CN116504453A - High-voltage cable, high-voltage cable preparation method and vertical combustion test device - Google Patents

Abstract

The application provides a high-voltage cable, a high-voltage cable preparation method and a vertical combustion test device, wherein the high-voltage cable comprises a conductor, an insulating layer arranged outside the conductor, a semiconductive water blocking tape layer arranged outside the insulating layer, a metal sleeve arranged outside the semiconductive water blocking tape layer and a sheath layer arranged outside the metal sleeve; the metal sleeve is a smooth copper sleeve, the inner peripheral surface of the metal sleeve is a smooth curved surface, and the smooth curved surface is abutted with the outer peripheral surface of the semiconductive water blocking tape layer; the high-voltage cable further comprises a temperature measuring optical fiber, wherein the temperature measuring optical fiber is wrapped in the conductor and is used for monitoring the temperature of the conductor. The high-voltage cable preparation method comprises the steps of blowing a cable core into a smooth copper sleeve through an air blowing process, and fixing the smooth copper sleeve outside the cable core through a necking device. The vertical combustion test device comprises a fixing frame and at least two combustion components, wherein the fixing frame enables the high-voltage cable to be arranged along the vertical direction; at least two burning components set up along the vertical direction, and burning component sets up in the one side of high voltage cable along the horizontal direction for burn high voltage cable.

Description

High-voltage cable, high-voltage cable preparation method and vertical combustion test device

Technical Field

The application relates to the technical field of cables, in particular to a high-voltage cable, a high-voltage cable preparation method and a vertical combustion test device.

Background

In pumped storage power stations and hydropower station projects, high-voltage cables with high flame retardance are increasingly used for ensuring safe and stable transportation of high-voltage electricity. In this project, the high-voltage cable generally includes a conductor, an insulating layer, a semiconductive water-blocking tape layer, a metal sleeve and a sheath layer, which are disposed from inside to outside, and although the flame retardance of the cable is improved to a certain extent, the safety of the cable operation cannot be ensured, and the temperature state of the inner cable core during the cable operation cannot be monitored. Meanwhile, these high-voltage cables are mostly in a vertically laid state of high drop. However, most of the metal sleeves of the high-voltage cables adopt corrugated copper sleeves or corrugated aluminum sleeves, gaps exist between the metal sleeves and the semiconductive water blocking tape layers, so that the slippage between the metal sleeves and the semiconductive water blocking tape layers is large, the vertical laying of the cables is not facilitated, and meanwhile, the gaps between the metal sleeves and the semiconductive water blocking tape layers enable contact surfaces of the metal sleeves and the semiconductive water blocking tape layers to be insufficiently contacted, so that a discharge phenomenon occurs after potential difference occurs. Meanwhile, when the copper sleeve or the aluminum sleeve is connected with the cable core, a welding or extrusion process is mostly adopted, a welding line can be generated in the welding process, sand holes can be generated in the extrusion process, and the safe operation of the cable is not facilitated.

In addition, the high-voltage cable most needs to be subjected to vertical combustion test before leaving the factory, and at present, most vertical combustion test devices can only carry out combustion test on a single point position of the high-voltage cable and can not carry out combustion test on two or more point positions of the cable, so that the reliability of final test data is not high.

How to solve the above problems, it is needed to provide a high-voltage cable capable of monitoring the internal temperature environment of the cable core in real time and reducing the slippage between the metal sleeve and the semiconductive water blocking tape layer, and a method for manufacturing the high-voltage cable capable of improving the operation safety of the cable, and a vertical combustion test device capable of simultaneously performing combustion tests on a plurality of positioning of the high-voltage cable, which are considered by those skilled in the art.

Disclosure of Invention

The embodiment of the application provides a high-voltage cable, which comprises a conductor, an insulating layer arranged outside the conductor, a semiconductive water-blocking tape layer arranged outside the insulating layer, a metal sleeve arranged outside the semiconductive water-blocking tape layer and a sheath layer arranged outside the metal sleeve; the metal sleeve is a smooth copper sleeve, the inner circumferential surface of the metal sleeve is a smooth curved surface, and the smooth curved surface is abutted with the outer circumferential surface of the semiconductive water blocking tape layer; the high-voltage cable further comprises a temperature measuring optical fiber, wherein the temperature measuring optical fiber is arranged in the conductor in a wrapping mode and is used for monitoring the temperature of the conductor.

Further, the temperature measuring optical fiber and the conductor are coaxially arranged, and the conductor is uniformly wrapped on the periphery of the temperature measuring optical fiber.

Further, the thickness of the metal sleeve is 1 to 2mm.

Further, the metal sleeve is connected with the semiconductive water blocking tape layer in a necking mode.

Further, the sheath layer is made of polytetrafluoroethylene or polyvinyl chloride.

Further, the high-voltage cable further comprises a semiconductive belt layer, and the semiconductive belt layer is wrapped on the outer side of the conductor.

Further, the high-voltage cable further comprises a conductor shielding layer and an insulation shielding layer, wherein the conductor shielding layer is arranged between the semiconductive belt layer and the insulation layer, and the insulation shielding layer is arranged between the insulation layer and the semiconductive water blocking belt layer.

Further, the high-voltage cable further comprises an anti-corrosion layer and a flame-retardant semi-conductive layer, wherein the anti-corrosion layer is arranged between the metal sleeve and the sheath layer, and the flame-retardant semi-conductive layer is wrapped on the periphery of the sheath layer.

The embodiment of the application also provides a high-voltage cable preparation method, which is used for preparing the high-voltage cable and comprises the following steps:

s1, a conductor, a semi-conductive tape layer, a conductor shielding layer, an insulating shielding layer and a semi-conductive water blocking tape layer are arranged outside a temperature measuring optical fiber from inside to outside in a coating manner, so that a cable core is manufactured;

s2, blowing the cable core into the metal sleeve through high-speed compressed air equipment, and enabling the metal sleeve to be relatively fixed with the cable core after being necked through a necking device;

s3, coating an anti-corrosion layer, a sheath layer and a flame-retardant semi-conductive layer outside the metal sleeve from inside to outside.

The embodiment of the application also provides a vertical combustion test device for vertical combustion test of high-voltage cable, include:

the fixing frame is used for fixing the high-voltage cable and enabling the high-voltage cable to be arranged in the vertical direction;

the burning assembly is arranged along the vertical direction, the burning assembly is arranged on one side of the high-voltage cable along the horizontal direction, and the burning assembly is used for burning the high-voltage cable.

Compared with the prior art, the high-voltage cable has the advantages that the temperature measuring optical fiber is wrapped in the conductor, the temperature inside the conductor can be monitored in real time, the use safety of the high-voltage cable is guaranteed, the metal sleeve is arranged to be a smooth copper sleeve, the structure of the whole high-voltage cable is more compact, the slippage between the metal sleeve and the semiconductive water blocking tape layer is reduced, and the high-voltage cable is more suitable for a vertically laid place with high drop. Meanwhile, no gap exists between the smooth copper sleeve and the semiconductive water blocking tape layer, so that the contact surfaces of the smooth copper sleeve and the semiconductive water blocking tape layer can be ensured to be fully contacted, and the phenomenon of discharge after potential difference is generated due to insufficient contact of the contact surfaces is avoided. According to the high-voltage cable preparation method, the cable core is blown into the metal sleeve by adopting the air blowing process, the metal sleeve and the cable core are fixed by the necking device, and compared with the welding process and the extrusion process, inert gas is not required to be used as protective gas, a high-power welding machine and an aluminum extruder are not required to be used, so that materials and electric energy are saved, and the production cost of the whole high-voltage cable is greatly reduced. The vertical combustion test device can simultaneously carry out combustion test on a plurality of points of the high-voltage cable by arranging a plurality of combustion assemblies along the vertical direction, so that the reliability of data of the high-voltage cable combustion test is improved.

Drawings

Fig. 1 is a schematic cross-sectional view of a high voltage cable according to an embodiment of the present application.

Fig. 2 is a schematic structural view of a metal sleeve of a high-voltage cable according to an embodiment of the present application.

Fig. 3 is a schematic structural diagram of a semiconductive water blocking tape layer of a high voltage cable according to an embodiment of the present application.

Fig. 4 is a schematic structural view of a vertical combustion test apparatus according to an embodiment of the present application.

Description of main reference numerals:

high voltage cable 100

Temperature measuring optical fiber 1

Conductor 2

Wire 201

Semiconductive belt layer 3

Conductor shielding layer 4

Insulating layer 5

Insulating shielding layer 6

Semiconductive water-blocking tape layer 7

Semiconductive substrate 701

Water-blocking substrate 702

Metal sleeve 8

Smooth curved surface 801

Anticorrosive layer 9

Sheath layer 10

Flame retardant semiconductive layer 11

Vertical combustion test apparatus 200

Fixing frame 210

Combustion assembly 220

The following detailed description will further illustrate the application in conjunction with the above-described figures.

Detailed Description

The following description will refer to the accompanying drawings in order to more fully describe the present application. Exemplary embodiments of the present application are illustrated in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. These exemplary embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the application to those skilled in the art. Like reference numerals designate identical or similar components.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, as used herein, "comprises" and/or "comprising" and/or "having," integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, and/or groups thereof.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Furthermore, unless the context clearly defines otherwise, terms such as those defined in a general dictionary should be construed to have meanings consistent with their meanings in the relevant art and the present application, and should not be construed as idealized or overly formal meanings.

The following detailed description of specific embodiments of the present application refers to the accompanying drawings.

Referring to fig. 1 and 2, a high voltage cable 100 of the present application includes a conductor 2, an insulating layer 5 disposed outside the conductor 2, a semiconductive water blocking tape layer 7 disposed outside the insulating layer 5, a metal sheath 8 disposed outside the semiconductive water blocking tape layer 7, and a sheath layer 10 disposed outside the metal sheath 8. The metal sleeve 8 is a smooth copper sleeve, the inner circumferential surface of the metal sleeve 8 is a smooth curved surface 801, and the smooth curved surface 801 is abutted with the outer circumferential surface of the semiconductive water blocking tape layer 7; the high-voltage cable 100 further comprises a temperature measuring optical fiber 1, wherein the temperature measuring optical fiber 1 is wrapped in the conductor 2 and is used for monitoring the temperature of the conductor 2.

Specifically, the metal sleeve 8 is arranged in a circular ring structure and is sleeved on the periphery of the semiconductive water blocking tape layer 7. The metal sleeve 8 is made of copper material, has higher fire resistance than the aluminum sleeve, and has excellent resistivity (resistivity not more than 0.01707 Ω·mm) ² /m). Compared with the metal sleeve 8 made of aluminum, the metal sleeve 8 made of copper can reach 50kA-200kA under the short-circuit time of 1s, and when the metal sleeve 8 made of copper bears the same short-circuit current, the wall thickness of the metal sleeve 8 made of copper can be smaller than that of the metal sleeve 8 made of aluminum, so that the thickness of the metal sleeve 8 is reduced, the outer diameter of the whole high-voltage cable 100 is further reduced, the transportation cost is reduced, and the bending performance of the high-voltage cable 100 is improved. In addition, the stability of the copper material is better than that of the aluminum material, when the aluminum material is adopted, the aluminum material is easy to react with the semiconductive water blocking tape layer 7 electrochemically, aluminum ions are separated out, and metal is causedThe jacket 8 is corroded, affecting the service life of the high voltage cable 100.

Meanwhile, the metal sleeve 8 adopts a smooth copper sleeve, the inner peripheral surface of the smooth copper sleeve is a smooth curved surface 801, so that the metal sleeve 8 is in surface contact with the outer peripheral wall of the semiconductive water blocking tape layer 7, and compared with a corrugated copper sleeve, on one hand, the smooth copper sleeve enables the structure of the whole high-voltage cable 100 to be more compact, and the slippage between the metal sleeve 8 and the semiconductive water blocking tape layer 7 is reduced, so that the high-voltage cable 100 is more suitable for a vertically laid place with high drop. On the other hand, no gap exists between the smooth copper sleeve and the semiconductive water blocking tape layer 7, so that the contact surfaces of the smooth copper sleeve and the semiconductive water blocking tape layer 7 can be ensured to be fully contacted, and the phenomenon of discharge after potential difference is generated due to insufficient contact of the contact surfaces is avoided.

Referring to fig. 1 again, the temperature measuring optical fiber 1 and the conductor 2 are coaxially arranged, and the conductor 2 is uniformly wrapped on the outer side of the temperature measuring optical fiber 1. In some embodiments, the conductor 2 is stranded with a plurality of wires 201, capable of carrying an electrical current. The section of the single wire 201 is circular, and the section of the whole conductor 2 formed by twisting the plurality of wires 201 is circular. The conductor 2 may be made of copper or aluminum.

The temperature measuring optical fiber 1 is arranged at the center of the conductor 2 and keeps consistent with the extending direction and the extending length of the conductor 2, so that the actual running temperature of the conductor 2 can be monitored in real time, and the use safety of the high-voltage cable 100 is ensured. In addition, the temperature measuring optical fiber 1 is directly wrapped in the conductor 2, so that the monitored temperature data of the conductor 2 can be more visual and accurate.

Referring to fig. 1 again, the high voltage cable 100 further includes a semiconductive belt layer 3, and the semiconductive belt layer 3 is wrapped around the outer side of the conductor 2. In one embodiment, the semiconductive belt layer 3 is disposed in a circular structure and is wrapped around the outer periphery of the conductor 2, so as to uniformly apply the electric field to the conductor 2.

Referring to the drawings again, the insulating layer 5 is made of crosslinked polyethylene. In one embodiment, the insulating layer 5 is disposed in a ring structure and is wrapped around the outer periphery of the semiconductive belt layer 3, so as to insulate the conductor 2. The insulating layer 5 is made of crosslinked polyethylene, so that the insulating layer has excellent insulativity, can well shield an electric field, has good bending property, and is convenient for bending when the high-voltage cable 100 is routed.

In particular, in other embodiments, the material of the insulating layer 5 may be natural rubber, silicone rubber, polyvinyl chloride or polyethylene.

Referring to fig. 1 again, the high voltage cable 100 further includes a conductive shielding layer 4, and the conductive shielding layer 4 is disposed between the semiconductive belt layer 3 and the insulating layer 5. In one embodiment, the conductive shielding layer 4 is made of a conductive material or a semiconductive material with low resistivity, so as to further uniformly generate the electric field by the conductor 2. The conductor shielding layer 4 is arranged in a circular ring structure and is respectively in surface contact with the semiconductive belt layer 3 and the insulating layer 5, so that the phenomenon of partial discharge caused by air gap between the conductor 2 and the insulating layer 5 can be avoided.

Referring to fig. 3 again and referring to fig. 1, the high voltage cable 100 further includes an insulation shielding layer 6, wherein the insulation shielding layer 6 is disposed between the insulation layer 5 and the semiconductive water blocking tape layer 7. In one embodiment, the semiconductive water blocking tape layer 7 includes two semiconductive substrates 701 and a water blocking substrate 702, and the water blocking substrate 702 is sandwiched between the two semiconductive substrates 701, which can play a role in longitudinal and radial water blocking. The semiconductive substrate 701 is made of a semiconductive compound, and the water-blocking substrate 702 is made of powdery high-molecular water-absorbing material and conductive carbon black.

The insulating shielding layer 6 is made of a semiconductive material with low resistivity, and is in surface contact with the insulating layer 5 and the semiconductive water blocking tape layer 7, so that the phenomenon of partial discharge caused by gaps between the insulating layer 5 and the semiconductive water blocking tape layer 7 can be avoided.

Referring again to fig. 1, the thickness of the metal sleeve 8 is 1 to 2mm. In one embodiment, the thickness of the metal sleeve 8 may be one of 1.1mm,1.2mm,1.3mm,1.4mm,1.5mm,1.6mm,1.7mm,1.8mm,1.9 mm. The metal sleeve 8 is sleeved on the periphery of the semiconductive water blocking tape layer 7, so that the insulating layer 5 coated by the semiconductive water blocking tape layer 7 can be prevented from being damaged, and the metal sleeve 8 can also shield an electric field. The metal sleeve 8 is made of copper, and when the high-voltage cable 100 has a ground fault and short-circuit current occurs, the short-circuit current allowed to pass through the metal sleeve 8 of the copper is larger than that of aluminum.

In particular, the metal sleeve 8 is attached to the semiconductive water-blocking tape layer 7 by means of a constriction.

Referring to fig. 1 again, the high voltage cable 100 further includes an anti-corrosion layer 9 and a flame retardant semiconductive layer 11, wherein the anti-corrosion layer 9 is disposed between the metal sleeve 8 and the sheath layer 10, and the flame retardant semiconductive layer 11 is wrapped around the sheath layer 10. In an embodiment, the anti-corrosion layer 9 is made of a flame retardant material, such as a flame retardant hot melt adhesive, and the anti-corrosion layer 9 is sleeved on the outer periphery of the metal sleeve 8, so that the metal sleeve 8 can be protected and the metal sleeve 8 is prevented from being corroded.

In particular, the outer peripheral surface of the metal sleeve 8 may be provided as a smooth curved surface 801 or a corrugated curved surface. When the outer peripheral surface of the metal sleeve 8 is formed into the smooth curved surface 801, the outer peripheral surface of the metal sleeve 8 is brought into surface contact with the inner peripheral surface of the anticorrosive layer 9, and the amount of slippage therebetween is reduced. When the outer peripheral surface of the metal sleeve 8 is formed into a corrugated curved surface, the outer peripheral gap of the metal sleeve 8 may be filled with the anti-corrosive layer 9, so that the outer peripheral surface of the metal sleeve 8 is in surface contact with the inner peripheral surface of the anti-corrosive layer 9.

The flame-retardant semiconductive layer 11 is a composite structure formed by semiconductive material and flame-retardant material, the flame-retardant material can be polyimide coating, etc., and the semiconductive material can be semiconductive graphite, etc. The flame-retardant semiconductive layer 11 is coated on the outer periphery of the sheath layer 10 by a coating process or an extrusion process, and can be used as an external electrode of the sheath layer 10 of the high-voltage cable 100 when a voltage withstand test is performed, and can reduce the capacitive discharge of the high-voltage cable 100. In addition, the flame retardant semiconductive layer 11 has good crusting performance when burning, thereby improving the flame retardant performance of the entire high voltage cable 100.

Referring to fig. 1 again, the material of the sheath layer 10 is polytetrafluoroethylene or polyvinyl chloride. In one embodiment, the sheath layer 10 is sleeved on the outer periphery of the anti-corrosion layer 9, and has waterproof, flame-retardant and insulating properties, so as to protect the internal structure of the high-voltage cable 100. When polytetrafluoroethylene is adopted as the material of the sheath layer 10, the sheath layer also has oil resistance, can be compatible with the material of the internal insulating oil of the wiring end of the high-voltage cable 100, ensures the safe operation of the high-voltage cable 100, ensures that the high-voltage cable 100 can burn for 90min under high-temperature flame of not lower than 750 ℃ and the optical fiber is continuous for 30min after the fire is stopped, and can meet the requirement that the optical fiber can still continue to work when the high-voltage cable 100 breaks out of fire.

In summary, the high-voltage cable 100 of the present application sequentially comprises, from inside to outside, the temperature measuring optical fiber 1, the conductor 2, the semiconductive tape layer 3, the conductor shielding layer 4, the insulating layer 5, the insulating shielding layer 6, the semiconductive water blocking tape layer 7, the metal sleeve 8, the anti-corrosion layer 9, the sheath layer 10 and the flame retardant semiconductive layer 11. The metal sleeve 8 adopts a smooth copper sleeve, so that the structure of the whole high-voltage cable 100 is more compact, the slippage between the metal sleeve 8 and the semiconductive water blocking tape layer 7 is reduced, the high-voltage cable 100 is more suitable for a vertically laid place with high drop, the outer diameter of the metal sleeve 8 is reduced, the flexibility of the high-voltage cable 100 is improved, and the high-voltage cable 100 has better mechanical properties. And no gap exists between the smooth copper sleeve and the semiconductive water blocking tape layer 7, so that the contact surfaces of the smooth copper sleeve and the semiconductive water blocking tape layer 7 can be fully contacted, the phenomenon of discharge after potential difference caused by insufficient contact of the contact surfaces is avoided, and the operation safety of the high-voltage cable 100 is improved.

Meanwhile, the temperature measuring optical fiber 1 can monitor the temperature inside the conductor 2 in a whole line, and the operation safety of the high-voltage cable 100 is ensured. The conductor shielding layer 4 and the insulating shielding layer 6 can be used for homogenizing an electric field, and avoiding the phenomenon of partial discharge, and further ensuring the operation safety of the high-voltage cable 100. The anti-corrosion layer 9, the sheath layer 10 and the flame-retardant semi-conductive layer 11 which are externally arranged on the metal sleeve 8 can greatly improve the flame retardance of the high-voltage cable 100, so that the high-voltage cable 100 meets the A-class bunching combustion requirement, and the corrosion resistance and the oil resistance of the high-voltage cable 100 are improved. Therefore, through the combined use of the temperature measuring optical fiber 1, the conductor 2, the semiconductive belt layer 3, the conductor shielding layer 4, the insulating layer 5, the insulating shielding layer 6, the semiconductive water blocking belt layer 7, the metal sleeve 8, the anti-corrosion layer 9, the sheath layer 10 and the flame-retardant semiconductive layer 11, the molded high-voltage cable 100 not only has excellent safety, flame retardance, corrosion resistance and oil resistance, but also meets the A-class bundled combustion requirement.

The method for preparing the high-voltage cable is used for preparing the high-voltage cable 100, and comprises the following steps:

s1, a conductor 2, a semiconductive belt layer 3, a conductor shielding layer 4, an insulating layer 5, an insulating shielding layer 6 and a semiconductive water blocking belt layer 7 are coated outside the temperature measuring optical fiber 1 from inside to outside to manufacture a cable core.

In this step, a plurality of wires 201 are uniformly wrapped around the outer circumference of the temperature measurement optical fiber 1, the plurality of wires 201 are hinged to form a conductor 2, and finally, a semiconductive tape layer 3, a conductor shielding layer 4, an insulating layer 5, an insulating shielding layer 6, and a semiconductive water blocking tape layer 7 are wrapped around the outer circumference of the conductor 2 from inside to outside.

S2, blowing the cable core into the metal sleeve 8 through high-speed compressed air equipment, and fixing the metal sleeve 8 and the cable core relatively after necking through a necking device.

Wherein, step S2 includes the following steps:

s21, injecting water into the smooth copper sleeve, cleaning internal impurities of the smooth copper sleeve, sealing one end of the smooth copper sleeve through a sealing sleeve after cleaning is completed, then sealing the other end of the smooth copper sleeve after 5-10 MPa of compressed air is introduced into the smooth copper sleeve, and finally detecting the change of the internal air pressure of the smooth copper sleeve to judge whether the sealing performance of the smooth copper sleeve is abnormal.

S22, connecting the high-speed compressed air device into one end of the smooth copper sleeve, which is far away from the sealing sleeve, injecting 5000-10000 MPa compressed air into the smooth copper sleeve, and then pulling one end of the cable core into the smooth copper sleeve from one end of the smooth copper sleeve, which is far away from the sealing sleeve, through the cable core conveying device until the cable core is completely positioned in the smooth copper sleeve.

S23, pulling the smooth copper sleeve to pass through the necking device, and gradually clamping the smooth copper sleeve after the necking device acts, so that the outer diameter of the smooth copper sleeve is gradually reduced until the smooth copper sleeve is used for fixing the cable core covered by the smooth copper sleeve.

It is worth noting that, because of the larger linear expansion coefficient and shrinkage rate of copper, the dies adopted by the diameter reducing device are made of tungsten steel, and the apertures of the dies arranged from the initial end of the smooth copper sleeve are sequentially arranged from large to small.

S3, an anti-corrosion layer 9, a sheath layer 10 and a flame-retardant semiconductive layer 11 are coated outside the metal sleeve 8 from inside to outside.

Thus, according to the high-voltage cable preparation method, the cable core is blown into the metal sleeve 8 through the air blowing process, the metal sleeve 8 and the cable core are fixed through the necking device, and compared with the welding process and the extrusion process, inert gas is not required to be used as protective gas, a high-power welding machine and an aluminum extruder are not required to be used, so that materials and electric energy are saved, and the production cost of the whole high-voltage cable 100 is greatly reduced.

Referring to fig. 4, a vertical combustion test apparatus 200 of the present application is used for a vertical combustion test of a high-voltage cable 100, and includes a fixing frame 210 and at least two combustion assemblies 220, wherein the fixing frame 210 is used for fixing the high-voltage cable 100, and setting up the high-voltage cable 100 along a vertical direction; at least two combustion assemblies 220 are disposed along a vertical direction, and the combustion assemblies 220 are disposed along a horizontal direction at one side of the high voltage cable 100, the combustion assemblies 220 being used for burning the high voltage cable 100.

The combustion test is used as a part of a flame-retardant cable monitoring link, can simulate the combustion condition of the flame-retardant cable, and analyzes the performance of the flame-retardant cable according to the data such as the heat release rate and the total heat release amount when the flame-retardant cable burns.

Specifically, the fixing frame 210 is provided with a plurality of clamps (not shown in the figure), and the plurality of clamps are sequentially arranged along the vertical direction, so that different parts of the high-voltage cable 100 can be clamped, the high-voltage cable 100 is ensured to be laid along the vertical direction, and the state that the high-voltage cable 100 is vertically laid in the environment with high drop height is accurately simulated.

The combustion assembly 220 is at least two and is capable of performing combustion testing on at least two points of the high voltage cable 100, thereby increasing the sampling points. The combustion assembly 220 is mounted on the fixing frame 210 and located at one side of the high-voltage cable 100 along the horizontal direction, so as to intensively burn the test points of the high-voltage cable 100. The combustion assembly 220 is preferably a torch that can fire the high-voltage cable 100 after spraying high-temperature flame, and the plurality of combustion assemblies 220 can fire different points of the high-voltage cable 100 at the same time. Thus, the vertical combustion test device 200 of the present application can perform combustion test on a plurality of points of the high-voltage cable 100 at the same time, thereby improving the reliability of data of the combustion test of the high-voltage cable 100.

When the vertical combustion test device 200 is used for carrying out the combustion test on the high-voltage cable 100, the test standard is according to the national standard GB/T18380.33-2022, the fire supply time is 40min, and the maximum carbonization height of the sample is measured to be less than or equal to 0.8m under two ignition sources (the standard is a single ignition source). It can be seen that the high voltage cable 100 of the present application is excellent in flame retardant performance.

Hereinabove, the specific embodiments of the present application are described with reference to the accompanying drawings. However, those of ordinary skill in the art will appreciate that various modifications and substitutions can be made to the specific embodiments of the present application without departing from the scope thereof. Such modifications and substitutions are intended to be within the scope of the present application.

Claims (10)

1. A high-voltage cable comprises a conductor, an insulating layer arranged outside the conductor, a semiconductive water blocking tape layer arranged outside the insulating layer, a metal sleeve arranged outside the semiconductive water blocking tape layer and a sheath layer arranged outside the metal sleeve; the metal sleeve is a smooth copper sleeve, the inner circumferential surface of the metal sleeve is a smooth curved surface, and the smooth curved surface is abutted with the outer circumferential surface of the semiconductive water blocking tape layer; the high-voltage cable further comprises a temperature measuring optical fiber, wherein the temperature measuring optical fiber is arranged in the conductor in a wrapping mode and is used for monitoring the temperature of the conductor.

2. The high voltage cable of claim 1, wherein the temperature sensing optical fiber is disposed coaxially with the conductor, and the conductor is uniformly wrapped around the outer circumference of the temperature sensing optical fiber.

3. The high voltage cable of claim 1, wherein the metal sleeve has a thickness of 1 to 2mm.

4. The high voltage cable of claim 1, wherein said metal jacket is attached to said semiconductive water blocking tape layer in a necked down fashion.

5. The high voltage cable of claim 1, wherein the jacket layer is made of polytetrafluoroethylene or polyvinyl chloride.

6. The high voltage cable of claim 1, further comprising a semiconductive tape layer wrapped around the outside of the conductor.

7. The high voltage cable of claim 1, further comprising a conductor shield layer disposed between the semiconductive tape layer and the insulation layer and an insulation shield layer disposed between the insulation layer and the semiconductive water blocking tape layer.

8. The high voltage cable of claim 1, further comprising a corrosion protection layer disposed between the metal jacket and the jacket layer and a flame retardant semiconductive layer disposed around the jacket layer.

9. A method for manufacturing a high voltage cable according to any one of claims 1 to 8, comprising the steps of:

s1, coating the conductor, the semiconductive belt layer, the conductor shielding layer, the insulating shielding layer and the semiconductive water blocking belt layer outside the temperature measuring optical fiber from inside to outside to manufacture a cable core;

s2, blowing the cable core into the metal sleeve through high-speed compressed air equipment, and enabling the metal sleeve to be relatively fixed with the cable core after being necked through a necking device;

and S3, coating the anti-corrosion layer, the sheath layer and the flame-retardant semiconductive layer outside the metal sleeve from inside to outside.

10. A vertical burn test apparatus for a vertical burn test of a high voltage cable according to any one of claims 1 to 8, comprising:

the fixing frame is used for fixing the high-voltage cable and enabling the high-voltage cable to be arranged in the vertical direction;

the burning assembly is arranged along the vertical direction, the burning assembly is arranged on one side of the high-voltage cable along the horizontal direction, and the burning assembly is used for burning the high-voltage cable.