CN112927848B

CN112927848B - Copper clad aluminum conductor low-smoke halogen-free A-class flame-retardant power cable

Info

Publication number: CN112927848B
Application number: CN202110095919.3A
Authority: CN
Inventors: 郭智昊
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-01-25
Filing date: 2021-01-25
Publication date: 2022-05-17
Anticipated expiration: 2041-01-25
Also published as: CN112927848A

Abstract

The invention relates to the technical field of cable equipment, and discloses a copper-clad aluminum conductor low-smoke halogen-free A-class flame-retardant power cable which comprises a cable body, wherein the cable body comprises an outer protective sleeve and a cable core, the outer protective sleeve comprises a first insulating layer, a metal shielding layer, a second insulating layer, a flame-retardant layer, a corrosion-resistant layer and an outer protective layer from inside to outside, the cable core is arranged in the first insulating layer, flame-retardant filler is filled in the flame-retardant layer, and the flame-retardant filler comprises the following components in parts by weight: 3-10 parts of aluminum hydroxide, 1-5 parts of magnesium chloride, 1-5 parts of basalt fiber, 1-3 parts of zinc borate, 1-3 parts of talcum powder, 1-5 parts of polyphosphoric acid and 5-10 parts of silicate.

Description

Copper clad aluminum conductor low-smoke halogen-free A-class flame-retardant power cable

Technical Field

The invention relates to the technical field of cable equipment, in particular to a copper-clad aluminum conductor low-smoke halogen-free class-A flame-retardant power cable.

Background

At present, along with the continuous improvement of science and technology level, middling pressure flame retarded cable range of application is more and more, lays the place more and more, and middling pressure flame retarded cable mostly adopts fire-retardant and reaches flame retardant efficiency around covering and sheath in the past, but this kind of effect can not be applicable to present development trend far away.

The combustion of the electric wire and cable is due to the generation of combustible gas by external heating, and three factors causing the combustion, namely combustible gas, heat and oxygen, must be suppressed in order to achieve the purpose of flame retardance. Therefore, flame-retardant electric wires and cables generally employ a method of adding halogen-containing halides and metal oxides to the sheath material, which is an excellent method in view of flame retardancy, but since these materials contain halides, they release a large amount of smoke and hydrogen halide gas when burned, so that visibility during fire is low, which causes a great hindrance to safe evacuation of people and fire fighting, and people are more suffocated to death by toxic gases.

With the increasing technological level, the flame retardant problem has been further developed from the conventional halogen flame retardant to the low halogen and halogen-free flame retardant. At present, the inner structure of a general low-smoke halogen-free fire-resistant power cable mainly adopts a fire-resistant layer wrapped outside a conductor, and an outer sheath adopts a low-smoke halogen-free material to achieve the performances of fire resistance, low smoke and no toxicity. However, the existing cable is often too short in fire resistance, cannot better adapt to the requirement of a high-temperature environment, and cannot send out combustion alarm information in time when the existing power cable is combusted.

Disclosure of Invention

Therefore, the copper clad aluminum conductor low-smoke halogen-free A-class flame-retardant power cable needs to be provided, and the problem that the existing flame-retardant cable is low in fire resistance is solved.

In order to achieve the purpose, the invention provides a copper-clad aluminum conductor low-smoke halogen-free class-A flame-retardant power cable which comprises a cable body, wherein the cable body comprises an outer protective sleeve and a cable core, the cable core comprises a conductor and an inner insulating layer extruded on the outer side surface of the conductor, and the conductor is formed by stranding a plurality of copper-clad aluminum single wires;

the outer protective sleeve comprises a first insulating layer, a metal shielding layer, a second insulating layer, a flame-retardant layer, an anti-corrosion layer and an outer protective layer from inside to outside, the cable core is arranged in the first insulating layer, and flame-retardant filler is filled in the flame-retardant layer;

the flame-retardant filler comprises the following components in parts by weight: 3-10 parts of aluminum hydroxide, 1-5 parts of magnesium chloride, 1-5 parts of basalt fiber, 1-3 parts of zinc borate, 1-3 parts of talcum powder, 1-5 parts of polyphosphoric acid and 5-10 parts of silicate.

Further, 5 parts of aluminum hydroxide, 4 parts of magnesium chloride, 2 parts of basalt fiber, 2 parts of zinc borate, 1 part of talcum powder, 3 parts of polyphosphoric acid and 8 parts of silicate.

Further, be equipped with first insulating layer and second insulating layer between first insulating layer and the second insulating layer, have the space between first insulating layer and the second insulating layer, form the nitrogen gas passageway, the both ends of cable body are equipped with nitrogen gas import and nitrogen gas export respectively, nitrogen gas import and nitrogen gas export all communicate with the nitrogen gas passageway, are equipped with the spliced pole in the nitrogen gas passageway, first insulating layer and second insulating layer are connected at the both ends of spliced pole. The connecting column supports the first insulating layer and the second insulating layer.

Further, be equipped with outside convex instruction shell on the second insulating layer, instruct the middle part that the shell extends to fire-retardant layer, it is connected with a connecting pipe to instruct the shell, the connecting pipe radially runs through second insulating layer, metallic shield and second insulating layer along the cable body, instruct the shell to pass through the connecting pipe and be connected with nitrogen gas passageway, be equipped with the high temperature indicator in instructing the shell, nitrogen gas outlet department is equipped with detecting element, the high temperature indicator is used for producing cable body combustion signal, detecting element is used for detecting cable body combustion signal.

Further, the high temperature indicator is sodium bicarbonate, and the detection unit comprises a carbon dioxide detector and a humidity detector. The sodium bicarbonate is heated and decomposed to generate carbon dioxide and water, and the carbon dioxide detector and the humidity detector perform double detection, so that the result is more accurate.

Further, still include cable joint, the quantity of cable body is a plurality of, be equipped with cooling channel on the cable body, two adjacent cable bodies are connected to cable joint's both sides, and the nitrogen gas import and the nitrogen gas export of two cable bodies are linked together through cooling channel, nitrogen gas import department is equipped with the air pump.

Further, the cable joint includes interior casing and shell body, interior casing sets up in the shell body, the space has between interior casing and the shell body, forms cooling channel, be equipped with the air vent on the shell body, air vent and cooling channel intercommunication, be provided with support piece in the cooling channel, interior casing and shell body are connected to support piece, the relative both sides face of shell body all is equipped with first interface, the relative both sides face of interior casing all is equipped with the second connector, first interface and second connector position are corresponding, and two adjacent cable bodies are interior electric connection including the casing, first interface and second connector have the adapter sleeve, be equipped with the blow vent on the adapter sleeve, nitrogen gas import and nitrogen gas export are linked together with cooling channel through the blow vent on two adapter sleeves respectively. Cooling channel surrounds interior casing, and when logical nitrogen gas, nitrogen gas also can cool down to interior casing, is favorable to the temperature of casing electric connection including the cable core.

Further, cable joint still including the adsorption unit, the separation of adsorption unit sets up in cooling channel, the adsorption unit includes carbon dioxide adsorption ring and drying ring, carbon dioxide adsorption ring and drying ring overlap in proper order on interior casing along the flow direction of nitrogen gas, carbon dioxide adsorption ring intussuseption is filled with the carbon dioxide adsorbent, drying ring intussuseption is filled with the drier. The normal use of the next section of cable body is prevented from being influenced by carbon dioxide and water generated by the decomposition of the high-temperature indicator of the section of cable body.

Furthermore, indicate shell and connecting pipe and be metal shielding material, the metal shielding layer is connected with the lateral surface of connecting pipe, the junction of instructing shell and connecting pipe is equipped with the interception net. In the nitrogen gas passageway was dropped to surperficial high temperature indicator, plugged up the nitrogen gas passageway, and instruct shell and connecting pipe to be metal shield material, avoided leading to the metal shielding effect of cable to weaken because the connecting pipe runs through the metal shielding layer.

Further, the first insulating layer is to being equipped with the connecting rod that the protrusion set up, the one end that the first insulating layer was kept away from to the connecting rod is equipped with solid fixed ring, and it has the buffering filler to fill between cable core and the first insulating layer. For the fixation of the cable core.

Further, the corrosion-resistant layer is made of carbon fiber composite resin, and the first insulating layer and the second insulating layer are made of cross-linked polyethylene.

The technical scheme has the following beneficial effects:

1. according to the invention, the flame-retardant material is filled with the inorganic compound, so that the requirements of no low smoke and no halogen can be met, the flame-retardant grade of the cable reaches A grade, and compared with the existing flame-retardant filler, the formula of the flame-retardant filler disclosed by the invention has a better flame-retardant effect.

2. The cable core protection sheath is also provided with the nitrogen channel, nitrogen enters the nitrogen channel from the nitrogen inlet, and heat generated by the load current of the cable core is continuously taken away in the flowing process of the nitrogen in the nitrogen channel, so that the service life of the outer protection sheath is prevented from being influenced by the high temperature generated by the cable core.

3. The high-temperature indicator is arranged in the flame-retardant layer, when the outside of the cable is in a combustion environment or the outside environment is too high, the high-temperature indicator can send a combustion signal and is detected by a detector at a nitrogen outlet, so that an alarm sound is sent, and a worker can determine a cable section to be combusted in time according to alarm information.

Drawings

Fig. 1 is a cross-sectional view of a cable body according to an embodiment.

Fig. 2 is a partial sectional view taken along line a-a of fig. 1.

Fig. 3 is a cross-sectional view of a cable connector according to an embodiment.

Description of the reference numerals:

1. a cable core; 11. a conductor; 12. an inner insulating layer;

2. an outer protective sheath; 21. a first insulating layer; 211. a connecting rod; 212. a fixing ring; 213. buffering the filler; 22. a metal shielding layer; 23. a second insulating layer; 231. an indicator housing; 232. a connecting pipe; 24. A flame retardant layer; 25. a corrosion-resistant layer; 26. an outer protective layer; 27. a nitrogen channel; 271. a first insulating layer; 272. a second insulating layer; 273. connecting columns; 28. a nitrogen outlet; 281. a carbon dioxide detector; 282. A moisture detector; 29. a nitrogen inlet;

3. a cable joint; 31. an outer housing; 311. a vent hole; 32. an inner housing; 33. a cooling channel; 331. A support member; 332. an air pump; 333. an adsorption unit; 3331. a carbon dioxide adsorption ring; 3332. drying the ring; 34. connecting sleeves; 341. and (4) a vent.

Detailed Description

To explain technical contents, structural features, and objects and effects of the technical solutions in detail, the following detailed description is given with reference to the accompanying drawings in conjunction with the embodiments.

Example 1

Referring to fig. 1-3, a copper clad aluminum conductor 11 low smoke zero halogen class a flame retardant power cable includes a cable body, the cable body includes an outer protective sleeve 2 and a cable core 1, the cable core 1 includes a conductor 11 and an inner insulating layer 12 extruded on an outer side surface of the conductor 11, the conductor 11 is formed by twisting a plurality of copper clad aluminum single wires;

outer protective sheath 2 is from inside to outside including first insulating layer 21, metal shielding layer 22, second insulating layer 23, fire-retardant layer 24, corrosion-resistant layer 25 and outer protective layer 26, cable core 1 sets up in first insulating layer 21, and fire-retardant layer 24 intussuseption is filled with fire-retardant filler, is equipped with first insulating layer 271 and second insulating layer 272 between first insulating layer 21 and the second insulating layer 23, has the space between first insulating layer 271 and the second insulating layer 272, forms nitrogen gas passageway 27, the both ends of cable body are equipped with nitrogen gas inlet 29 and nitrogen gas outlet 28 respectively, nitrogen gas inlet 29 and nitrogen gas outlet 28 all communicate with nitrogen gas passageway 27, are equipped with the spliced pole 273 in the nitrogen gas passageway 27, first insulating layer 271 and second insulating layer 272 are connected at the both ends of spliced pole 273. The connection posts 273 support the first and second insulation layers 271 and 272. Specifically a first insulation layer 271 and a second insulation layer 272.

The first insulating layer 21 is provided with a protruding connecting rod 211, a fixing ring 212 is arranged at one end, away from the first insulating layer 21, of the connecting rod 211, and a buffer filler 213 is filled between the cable core 1 and the first insulating layer 21. The cable core 1 is fixed, the corrosion-resistant layer 25 is made of carbon fiber composite resin, and the first insulating layer 21 and the second insulating layer 23 are made of cross-linked polyethylene.

Be equipped with outside convex instructing shell 231 on the second insulating layer 23, instruct the middle part that shell 231 extends to fire-retardant layer 24, it is connected with a connecting pipe 232 to instruct shell 231, connecting pipe 232 radially runs through second insulating layer 23, metallic shield layer 22 and second insulating layer 272 along the cable body, it is connected with nitrogen gas passageway 27 through connecting pipe 232 to instruct shell 231, be equipped with the high temperature indicator in instructing shell 231, nitrogen gas outlet 28 department is equipped with detecting element, the high temperature indicator is used for producing cable body combustion signal, detecting element is used for detecting cable body combustion signal. The high temperature indicator may be calcium oxalate, calcium carbonate, sodium bicarbonate or sodium carbonate, etc., and the choice of different compounds may be used to indicate different temperatures.

Indicate shell 231 and connecting pipe 232 to be metal shielding material, metal shielding layer 22 is connected with the lateral surface of connecting pipe 232, the junction of instructing shell 231 and connecting pipe 232 is equipped with the interception net. The surface high temperature indicator drops into the nitrogen channel 27 to block the nitrogen channel 27, and the indicating shell 231 and the connecting pipe 232 are made of metal shielding materials, so that the metal shielding effect of the cable caused by the fact that the connecting pipe 232 penetrates through the metal shielding layer 22 is prevented from being weakened. In this embodiment, the metal shielding layer 22 is a copper wire mesh grid, and the indicating shell 231 and the connecting pipe 232 are made of a steel material with a copper-plated surface.

In this embodiment, the high temperature indicator is sodium bicarbonate, and the detection unit includes a carbon dioxide detector 281 and a humidity detector 282. The sodium bicarbonate is heated and decomposed to generate carbon dioxide and water, and the carbon dioxide detector 281 and the humidity detector 282 perform double detection, so that the result is more accurate. Compared with the conventional electric signal connection detection, the method avoids the use of signal connection wires, and the carbon dioxide detector 281 and the humidity detector 282 can detect whether the increase amounts of carbon dioxide and water are in a 1:1 relationship when detecting the increase amounts of carbon dioxide and water, so that the sodium bicarbonate is heated and decomposed.

Specifically, the model of the carbon dioxide detector 281 is JSA5-CO2-IR, the model of the humidity detector 282 is THT-N163A, and the carbon dioxide detector 281 and the humidity detector 282 are connected with an alarm or a control center.

In this embodiment, two cable bodies are connected through a cable joint 3, further, the cable joint 3 includes an inner housing 32 and an outer housing 31, the inner housing 32 is disposed in the outer housing 31, a space is provided between the inner housing 32 and the outer housing 31 to form a cooling channel 33, an air vent 311 is disposed on the outer housing 31, the air vent 311 is communicated with the cooling channel 33, a support member 331 is disposed in the cooling channel 33, the support member 331 is connected with the inner housing 32 and the outer housing 31, two opposite side surfaces of the outer housing 31 are both provided with first connection ports, two opposite side surfaces of the inner housing 32 are both provided with second connection ports, the first connection ports and the second connection ports are corresponding in position, two adjacent cable bodies are electrically connected in the inner housing 32, the first connection ports and the second connection ports are provided with connection sleeves 34, the connection sleeves 34 are provided with air vents 341, the nitrogen inlet 29 and the nitrogen outlet 28 are respectively communicated with the cooling channel 33 through the air vents 341 on the two connecting sleeves 34, and the air pump 332 is arranged at the nitrogen inlet 29. The cooling channel 33 surrounds the inner shell 32, and when nitrogen is introduced, the nitrogen can also cool the inner shell 32, which is favorable for the electric connection temperature of the cable core 1 in the inner shell 32.

The vent hole 311 may be used to supplement nitrogen gas into the cable, or may be used as an outlet for nitrogen gas, and when the cable is not used, the vent hole 311 is blocked by a plug.

First interface is used for holding the cable body and passes through, the second connector is used for holding cable core 1 and passes through, it is concrete, the inside of interior casing 32 can be provided with multiunit linkage element, in this embodiment, the cable body has three cable core 1, be equipped with three group linkage element in the interior casing 32, linkage element includes the connection piece of two relative elastic sheets that set up and two elastic sheets of one connection, the cable core 1 of two cable bodies stretches into interior casing 32 back, the conductor 11 can be pushed down to the elastic sheet, realize two cable body's electricity from this and connect.

The cable joint 3 further comprises an adsorption unit 333, the adsorption unit 333 is arranged in the cooling channel 33 in a blocking mode, the adsorption unit 333 comprises a carbon dioxide adsorption ring 3331 and a drying ring 3332, the carbon dioxide adsorption ring 3331 and the drying ring 3332 are sequentially sleeved on the inner shell 32 along the flowing direction of nitrogen, a carbon dioxide adsorbent is filled in the carbon dioxide adsorption ring 3331, and a drying agent is filled in the drying ring 3332. The normal use of the next section of cable body is prevented from being influenced by carbon dioxide and water generated by the decomposition of the high-temperature indicator of the section of cable body.

In this embodiment, the carbon dioxide adsorbent is calcium hydroxide, and the desiccant is silica gel particles, so that the outer shell 31 may be configured as a detachable structure (not shown in the drawings) in order to facilitate installation of the internal structure of the circuit connector.

In the embodiment, the flame-retardant filler comprises the following components in parts by weight: 5 parts of aluminum hydroxide, 4 parts of magnesium chloride, 2 parts of basalt fiber, 2 parts of zinc borate, 1 part of talcum powder, 3 parts of polyphosphoric acid and 8 parts of silicate.

Example 2

The difference from the embodiment 1 is that the flame-retardant filler comprises the following components in parts by weight: 3 parts of aluminum hydroxide, 1 part of magnesium chloride, 1 part of basalt fiber, 1 part of zinc borate, 3 parts of talcum powder, 5 parts of polyphosphoric acid and 10 parts of silicate.

Example 3

The difference from the embodiment 1 is that the flame-retardant filler comprises the following components in parts by weight: 10 parts of aluminum hydroxide, 5 parts of magnesium chloride, 5 parts of basalt fiber, 3 parts of zinc borate, 1 part of talcum powder, 1 part of polyphosphoric acid and 5 parts of silicate.

The flame retardant grade in the market is the highest, namely the flame retardant grade A, the non-metallic substance capacity is 7L/m, the flame temperature is 815 ℃, the burning time is 40min, the carbonization height is not more than 2.5m,

the results of the flame retardant tests performed on the circuits of examples 1-3 are shown in Table 1:

TABLE 1 flame retardant performance of examples 1-3.

	Flame temperature/. degree.C	Burning time/min	Carbonization height/m	Oxygen index/%
					Example 1	850	60	0.8	45.3
Example 2	850	60	1.2	36.1
					Example 3	850	60	1.4	39.7

As can be seen from Table 1, the flame-retardant filler of the invention has good flame-retardant property, strong thermal stability and thermal decomposition resistance, and is suitable for cables at high temperature.

The invention is suitable for the cable connection environment with high temperature and complicated connection circuit, when in use, the power cable can be the structure of the cable body in the invention, the cable of the invention can also be used in the high temperature section, the other sections use the conventional cable, and the cable body of the invention can be connected through the cable joint 3.

The use process of the invention is as follows:

the plurality of cable bodies are connected by the cable joint 3 to form a cable line.

The vent holes 311 on the cable joint 3 at the head end of the cable line are used for ventilating nitrogen to the cooling channel 33, under the action of the air pump 332, the nitrogen channel 27 is used for feeding air, the nitrogen channel 27 continuously takes away heat dissipated due to current load of the cable core 1 in the flowing process, the nitrogen cools the inner shell 32 when flowing through the cooling channel 33 of the cable joint 3 in the middle of the cable line, the stability of connection with the cable core 1 is facilitated, the vent holes 311 on the cable joint 3 in the middle play a role in supplementing nitrogen, and the nitrogen finally flows out of the cable joint 3 at the tail end of the cable line;

when the environment outside the cable burns, the flame-retardant layer 24 of the invention can play a good flame-retardant role, meanwhile, due to the high temperature outside, the sodium bicarbonate in the indicating shell 231 is decomposed to generate carbon dioxide and water, the carbon dioxide and the water flow out from the nitrogen outlet 28 along with the nitrogen, the carbon dioxide detector 281 and the humidity detector 282 can accurately and frequently come out, and an alarm indication is sent out to inform the working personnel to check and extinguish the fire in time, thereby effectively avoiding the further expansion of the combustion condition.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or terminal that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or terminal. Without further limitation, an element defined by the phrases "comprising … …" or "comprising … …" does not exclude the presence of additional elements in a process, method, article, or terminal that comprises the element. Further, herein, "greater than," "less than," "more than," and the like are understood to exclude the present numbers; the terms "above", "below", "within" and the like are to be understood as including the number.

Although the embodiments have been described, once the basic inventive concept is obtained, other variations and modifications of these embodiments can be made by those skilled in the art, so that the above embodiments are only examples of the present invention, and not intended to limit the scope of the present invention, and all equivalent structures or equivalent processes using the contents of the present specification and drawings, or any other related technical fields, which are directly or indirectly applied thereto, are included in the scope of the present invention.

Claims

1. A low-smoke halogen-free A-class flame-retardant power cable with a copper-clad aluminum conductor is characterized by comprising a cable body, wherein the cable body comprises an outer protective sleeve and a cable core, the cable core comprises a conductor and an inner insulating layer extruded on the outer side surface of the conductor, and the conductor is formed by stranding a plurality of copper-clad aluminum single wires;

the flame-retardant filler comprises the following components in parts by weight: 3-10 parts of aluminum hydroxide, 1-5 parts of magnesium chloride, 1-5 parts of basalt fiber, 1-3 parts of zinc borate, 1-3 parts of talcum powder, 1-5 parts of polyphosphoric acid and 5-10 parts of silicate,

a first isolation layer and a second isolation layer are arranged between the first insulation layer and the second insulation layer, a space is arranged between the first isolation layer and the second isolation layer to form a nitrogen channel, a nitrogen inlet and a nitrogen outlet are respectively arranged at two ends of the cable body, the nitrogen inlet and the nitrogen outlet are both communicated with the nitrogen channel, a connecting column is arranged in the nitrogen channel, the two ends of the connecting column are connected with the first isolation layer and the second isolation layer,

the indicating shell is connected with a connecting pipe, the connecting pipe radially penetrates through the second insulating layer, the metal shielding layer and the second insulating layer along the radial direction of the cable body, the indicating shell is connected with a nitrogen channel through the connecting pipe, a high-temperature indicator is arranged in the indicating shell, a detection unit is arranged at a nitrogen outlet, the high-temperature indicator is used for generating a cable body combustion signal, and the detection unit is used for detecting the cable body combustion signal,

the high temperature indicator is sodium bicarbonate, and the detection unit comprises a carbon dioxide detector and a humidity detector.

2. The copper-clad aluminum conductor low-smoke halogen-free A-class flame-retardant power cable as claimed in claim 1, wherein the flame-retardant filler comprises the following components in parts by weight: 5 parts of aluminum hydroxide, 4 parts of magnesium chloride, 2 parts of basalt fiber, 2 parts of zinc borate, 1 part of talcum powder, 3 parts of polyphosphoric acid and 8 parts of silicate.

3. The copper-clad aluminum conductor low-smoke zero-halogen A-type flame-retardant power cable as claimed in claim 1, further comprising a plurality of cable connectors, wherein the cable bodies are provided with cooling channels, two adjacent cable bodies are connected to two sides of each cable connector, nitrogen inlets and nitrogen outlets of the two cable bodies are communicated through the cooling channels, and an air pump is arranged at the nitrogen inlet.

4. The copper-clad aluminum conductor low-smoke zero-halogen A-class flame-retardant power cable of claim 3, the cable joint comprises an inner shell and an outer shell, the inner shell is arranged in the outer shell, a space is arranged between the inner shell and the outer shell to form the cooling channel, the outer shell is provided with a vent hole which is communicated with the cooling channel, a support piece is arranged in the cooling channel, the supporting piece is connected with the inner shell and the outer shell, the two opposite side surfaces of the outer shell are respectively provided with a first connecting port, two opposite side surfaces of the inner shell are respectively provided with a second connector, the first connector and the second connector are corresponding in position, two adjacent cable bodies are electrically connected in the inner shell, the first connecting port and the second connecting port are provided with connecting sleeves, air vents are arranged on the connecting sleeves, and the nitrogen inlet and the nitrogen outlet are respectively communicated with the cooling channel through the air vents on the two connecting sleeves.

5. The copper-clad aluminum conductor low-smoke zero-halogen A-type flame-retardant power cable as claimed in claim 4, wherein the cable joint further comprises an adsorption unit, the adsorption unit is arranged in the cooling channel in a blocking manner, the adsorption unit comprises a carbon dioxide adsorption ring and a drying ring, the carbon dioxide adsorption ring and the drying ring are sequentially sleeved on the inner shell along the flowing direction of nitrogen, the carbon dioxide adsorption ring is internally filled with a carbon dioxide adsorbent, and the drying ring is internally filled with a drying agent.

6. The copper-clad aluminum conductor low-smoke zero-halogen A-type flame-retardant power cable as claimed in claim 1, wherein the indicating shell and the connecting pipe are both made of metal shielding materials, the metal shielding layer is connected with the outer side surface of the connecting pipe, and an intercepting net is arranged at the joint of the indicating shell and the connecting pipe.

7. The copper-clad aluminum conductor low-smoke zero-halogen A-class flame-retardant power cable as claimed in claim 1, wherein the first insulating layer is provided with a protruding connecting rod, one end of the connecting rod, which is far away from the first insulating layer, is provided with a fixing ring, and a buffer filler is filled between the cable core and the first insulating layer.

8. The copper-clad aluminum conductor low-smoke zero-halogen A-type flame-retardant power cable as claimed in any one of claims 1 to 7, wherein the corrosion-resistant layer is made of carbon fiber composite resin, and the first insulating layer and the second insulating layer are made of cross-linked polyethylene.