CN112821161A - Manufacturing method of maintenance-free high-voltage cable hot-melting T-shaped joint - Google Patents
Manufacturing method of maintenance-free high-voltage cable hot-melting T-shaped joint Download PDFInfo
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- 238000004519 manufacturing process Methods 0.000 title claims abstract description 16
- 238000003466 welding Methods 0.000 claims abstract description 84
- 238000009413 insulation Methods 0.000 claims abstract description 39
- 238000001816 cooling Methods 0.000 claims abstract description 38
- 238000000034 method Methods 0.000 claims abstract description 38
- 238000011084 recovery Methods 0.000 claims abstract description 21
- 238000005219 brazing Methods 0.000 claims abstract description 19
- 239000012943 hotmelt Substances 0.000 claims abstract description 18
- 239000000498 cooling water Substances 0.000 claims abstract description 16
- 239000004020 conductor Substances 0.000 claims abstract description 14
- 238000010438 heat treatment Methods 0.000 claims abstract description 13
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R43/00—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors
- H01R43/02—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors for soldered or welded connections
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R43/00—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors
- H01R43/20—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors for assembling or disassembling contact members with insulating base, case or sleeve
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Abstract
The invention discloses a manufacturing method of a maintenance-free high-voltage cable hot-melting T-shaped joint, which comprises the following steps: 1) and (3) cable welding: welding the wire cores of the three cables in a T shape in a silver-based brazing manner; 2) and (3) recovering the conductor shielding: wrapping a semi-conductive hot melt tape on the surface of a cable core; 3) and (3) insulation recovery: wrapping a main insulating layer on the outer layer of the semi-conductive hot melting belt, heating and welding, and rapidly cooling by adopting a cooling water jacket; 4) and (3) recovering the insulation shielding: after cooling the main insulating layer, wrapping a semi-conductive self-adhesive tape on the surface of the main insulating layer; 5) recovering the metal shield and the isolation sleeve, and then sticking and lapping copper shield layers at two ends by using a copper foil tape; 6) and (4) recovering the armor and the outer sheath. The invention initiates a three-cable welding method, accords with the national standard, reduces the use of the intermediate joint of two cables, reduces the complexity of a cable line, indirectly reduces the fault rate of the intermediate joint of the cables, and provides a new development direction for laying the power cable line.
Description
Technical Field
The invention relates to the technical field of cable connection, in particular to a manufacturing method of a maintenance-free high-voltage cable hot-melting T-shaped joint.
Background
With the increasing demand of urban power and the continuous improvement of urban power grids in the ground, the consumption of power cables is larger and larger. However, the number of faults of a cable line is also rising in sections, and in 2010, a survey report on the fault rate of a 10kV distribution network power cable in a certain city in China indicates that the fault rate of a cable middle joint is 45.3%, the fault rate of a terminal head is 6.6%, and the fault rate of a cable body is 4.4%. Therefore, traditional medium voltage cable accessories still have some problems in the use, especially 6 ~35 kV medium voltage power cable circuit in south area, because the environment is complicated along the cable, the rainwater is more, and a lot of cable circuit all soaks in the aquatic for a long time, traditional medium voltage cable connects because lack reliable dampproofing and waterproofing protection, moisture or moisture invade the cable, leads to medium voltage power cable circuit to connect the position fault rate higher, consequently, the melting joint technique begins to be applied to the more regional land power line use of rainwater in south. However, since the fusion is only used in the land cable in recent years, and only the fusion joints of the cables at two ends exist, the preparation process of the fusion joints in the land cable is quite immature, the prepared fusion joints need to be checked and maintained regularly, great inconvenience is brought to the use of the fusion joints used in the land, the fusion joints of the three cables cannot be successfully prepared by the existing fusion joint technology, and even if the three cables are welded together in a rigid manner, the stability and the resistance of the fusion joints of the three cables cannot reach the actual use standards of normal cable joints, so that the preparation process capable of welding the three cables together in a fusion manner is not found at present.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a manufacturing method of a maintenance-free high-voltage cable hot-melting T-shaped joint which is suitable for a land cable, has a novel process and can be used for welding three cables.
In order to achieve the purpose, the invention is realized by the following technical scheme: a manufacturing method of a maintenance-free high-voltage cable hot-melting T-shaped joint comprises the following steps:
(1) and (3) cable welding: welding the wire cores of the three cables in a T shape in a silver-based brazing manner;
(2) and (3) recovering the conductor shielding: wrapping a semi-conductive hot melt tape on the surface of a cable core;
(3) and (3) insulation recovery: wrapping a main insulating layer on the outer layer of the semi-conductive hot-melt belt, heating and welding, and rapidly cooling for not more than 2 h;
(4) and (3) recovering the insulation shielding: after cooling the main insulating layer, wrapping a semi-conductive self-adhesive tape on the surface of the main insulating layer;
(5) recovering the metal shielding and the isolating sleeve; then, the copper foil tape is used for sticking and lapping the copper shielding layers at two ends;
(6) and (3) restoring the armor and the outer sheath: wrapping a first layer of waterproof composite tape, and completely overlapping the outer sheaths of the ports of the cable; the ground wire is lapped on the steel armor at each port: and wrapping a second layer of waterproof composite tape, and completely overlapping the cable port outer sheath layer.
According to the technical scheme, the welding method of the three cables is initiated, and the welding spots are more complex and have higher resistance compared with the welding spots welded by the two cables due to the fact that the three cables are welded together, so that the resistance of a connector welded by the traditional two cables through exothermic welding is too large and cannot reach the national standard (GB/T1270), and the insulation protection method of the two cables cannot be applied due to the fact that the resistance is too large, the electric heat generated after the two cables are electrified, and the risk of ignition is extremely high. Therefore, the main technical points of the technical scheme are as follows:
firstly, the welding angles of the three cable joints are finally measured through a large number of experiments, the three cable joints are welded together in a T-shaped mode, the resistance at the welding point is minimum under the condition that the stability is ensured, and the welding difficulty is relatively low;
secondly, the three cable joints are welded in a layered silver-based brazing mode, and compared with the welding modes of heat-release welding, layered argon arc welding, layered silver brazing and brazing of common conductors, the welding point resistance of the welding position is lowest, and the national standard can be basically met;
thirdly, after the welding is finished, the structure of the welding spot of the three resistors is complex, and the resistors at the welding spot are still slightly higher than the welding mode of the two cables, so that in the insulation recovery process, the solidification effect of the insulating layer is enhanced by adopting a rapid cooling mode, the density, the stretching degree and the breaking tensile strain percentage of the insulating layer are improved, and the insulation requirement of the welding spot at the welding spot of the three cables is met.
In order to better implement the method of the present invention, further, in step (1), the specific process of cable welding is as follows:
(1.1) pretreating the wire cores of three cables needing to be connected, and customizing a T-shaped graphite mold;
(1.2) placing the wire cores of the three cables in a customized T-shaped graphite die, and adding brazing filler metal with the silver content of 25-35% and brazing powder for brazing; the type of the welding powder is QJ 101;
and (1.3) welding the wire cores by adopting a resistance welding machine in a layered welding mode, and processing the welding points of the wire cores to be smooth, free of bulges and free of burrs.
In order to better implement the method of the present invention, further, in step (1.1), the process of core pretreatment of the cable is as follows: and (3) eliminating the main insulation of the wire core to form a pencil stub of 50-60 mm, and polishing to leak the inner semi-conducting layer by 10-20 mm.
In order to better implement the method of the present invention, further, in (1.2), before the cores of the three cables are placed in the customized T-shaped graphite mold, the graphite mold and the cable cores to be welded need to be heated and dehumidified separately, the time for heating and dehumidifying graphite is 5 minutes, and the time for heating and dehumidifying cable cores is 1 minute.
In order to better implement the method of the present invention, further, in the step (2), the specific process of recovering the conductor shield is as follows: two layers of semi-conductive hot melting tapes are wrapped on the surface of a cable core, and the inner semi-conductive layer which is ground by completely lapping the cable core is 5-8 mm.
In order to better realize the method of the invention, further, in the step (3), the main insulating layer in the insulation recovery process mainly comprises an innermost polyethylene hot melt tape, an intermediate silicon rubber self-melt tape and an outer aluminum foil tape, and the winding strength of the main insulating layer is 280N/cm2No air gap is generated in the wrapping process.
In order to better realize the method, the lapping thickness of the polyethylene hot-melt tape is 2-3 mm, the width of the silicon rubber self-melt tape is 100mm, and the thickness of the aluminum foil tape is 0.5 mm.
In order to better implement the method of the present invention, in the step (3), the temperature for heating and welding the main insulating layer is 160 to 200 ℃ in the insulation recovery process.
In order to better implement the method of the present invention, in the step (3), in the insulation recovery process, the rapid cooling mode is that a cooling water bag is sleeved outside the main insulation layer, a water inlet and a water outlet are arranged in the cooling water bag, and the main insulation layer is cooled by the cooling water continuously flowing in the cooling water bag.
In order to better implement the method of the present invention, further, in the step (5), during the recovery process of the metal shielding and the isolation sleeve, the thickness of the copper foil strip is 0.5 mm.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) the invention provides a welding method of fusion joints of three cables, which comprehensively considers two aspects of a welding angle and a welding mode, so that the stability and the resistance of the fusion joints of the three cables all accord with national standards, and the fusion welding of the three cables is realized;
(2) in the insulation recovery process, the main insulation layer is rapidly cooled, so that the physical properties of the main insulation layer are remarkably improved, the insulation shielding main insulation layer can meet the insulation protection work of three cable fusion joints, in addition, the main insulation layer is rapidly cooled, the overall time of cable welding operation can be shortened, and positive reference significance is provided for welding two cable fusion joints;
(3) the invention initiates a welding method of three cable joints, the three-cable fusion joint prepared by the method meets the national standard, the use of the middle joint of two cables can be greatly reduced, the complexity of a cable line is reduced, the fault rate of the middle joint of the cable is indirectly reduced, and a new development direction is provided for laying a power cable line.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:
FIG. 1 is a schematic view of three cable joints of the present invention at different welding angles;
FIG. 2 is a linear relationship between different welding angles of three cable joints and the resistance of a fusion joint in the present invention;
Detailed Description
The present invention will be described in further detail with reference to the following examples for the purpose of making clear the objects, process conditions and advantages of the present invention, but the embodiments of the present invention are not limited thereto, and various substitutions and modifications can be made according to the common technical knowledge and the conventional means in the art without departing from the technical idea of the present invention described above, and the specific examples described herein are only for explaining the present invention and are not intended to limit the present invention.
Example 1:
the embodiment provides a manufacturing method of a maintenance-free high-voltage cable hot-melting T-shaped joint, which specifically comprises the following steps:
(1) and (3) cable welding: welding the wire cores of the three cables in a T shape in a silver-based brazing manner;
(2) and (3) recovering the conductor shielding: wrapping a semi-conductive hot melt tape on the surface of a cable core;
(3) and (3) insulation recovery: wrapping a main insulating layer on the outer layer of the semi-conductive hot-melt belt, heating and welding, and rapidly cooling for not more than 2 h;
(4) and (3) recovering the insulation shielding: after cooling the main insulating layer, wrapping a semi-conductive self-adhesive tape on the surface of the main insulating layer;
(5) recovering the metal shielding and the isolating sleeve: then, the copper foil tape is used for sticking and lapping the copper shielding layers at two ends;
(6) and (3) restoring the armor and the outer sheath: wrapping a first layer of waterproof composite tape, and completely overlapping the outer sheaths of the ports of the cable; the ground wire is lapped with the steel armor at each port; and wrapping a second layer of waterproof composite tape, and completely overlapping the cable port outer sheath layer.
Example 2:
on the basis of the foregoing embodiment, the present embodiment further defines a specific process of cable welding in step (1), specifically:
(1.1) pretreating the wire cores of three cables needing to be connected, and customizing a T-shaped graphite mold;
(1.2) placing the wire cores of the three cables in a customized T-shaped graphite die, and adding brazing filler metal with the silver content of 25-35% and brazing powder for brazing; the type of the welding powder is QJ 101;
and (1.3) welding the wire cores by adopting a resistance welding machine in a layered welding mode, and processing the welding points of the wire cores to be smooth, free of bulges and free of burrs.
In the step (1.1), the cable core pretreatment process comprises the following steps: eliminating the main insulation of the wire core to form a pencil stub of 50-60 mm, and polishing to leak the inner semi-conducting layer by 10-20 mm; in (1.2), before the sinle silk of three cables was arranged in the T shape graphite mould of customization in, need heat respectively except that the tide graphite mould and the cable core that needs the welding, the graphite heating time of removing the tide was 5 minutes, and the cable core heating time of removing the tide was 1 minute. Other parts of this embodiment are the same as those of the above embodiment, and are not described herein.
Example 3:
on the basis of the foregoing embodiment, the present embodiment further defines a specific process of recovering the conductor shield in step (2), specifically: two layers of semi-conductive hot melting tapes are wrapped on the surface of a cable core, and the inner semi-conductive layer which is ground by completely lapping the cable core is 5-8 mm. Other parts of this embodiment are the same as those of the above embodiment, and are not described herein.
Example 4:
on the basis of the above embodiment, the specific content of the step (3) is further defined, wherein the main insulating layer in the insulation recovery process is mainly composed of an innermost polyethylene hot melt tape, an intermediate silicone rubber self-melt tape, and an outer aluminum foil tape, and the winding strength of the main insulating layer is 280N/cm2No air gap is generated in the wrapping process; the wrapping thickness of the polyethylene hot-melt tape is 2-3 mm, the width of the silicon rubber self-melt tape is 100mm, and the thickness of the aluminum foil tape is 0.5 mm; in the insulation recovery process, the temperature for heating and welding the main insulation layer is 160-200 ℃. Other parts of this embodiment are the same as those of the above embodiment, and are not described herein.
Example 5:
in this embodiment, on the basis of the above embodiment, in the step (3), the rapid cooling mode in the insulation recovery process is water cooling, specifically: and a cooling water bag is sleeved outside the main insulating layer, a water inlet and a water outlet are formed in the cooling water bag, and the main insulating layer is cooled by the cooling water which continuously flows in the cooling water bag. Other parts of this embodiment are the same as those of the above embodiment, and are not described herein.
Example 6:
in this embodiment, specific content of the step (5) is further defined on the basis of the above embodiment, and in the process of recovering the metal shielding and the isolation sleeve, the thickness of the copper foil strip is 0.5 mm. Other parts of this embodiment are the same as those of the above embodiment, and are not described herein.
Example 7:
in order to verify the influence of the welding angles of the three cable joints on the resistance of the welding point, the following experiment is specially performed:
three cable joints are welded at 30 degrees, 45 degrees, 60 degrees and 90 degrees, as shown in figure 1, a conductor direct current resistance test is carried out according to GB/T12706, the resistance of fusion joints at different welding angles is measured respectively, the welding mode is the traditional heat release welding, and an expansion test is carried out, namely the influence of various welding angles on the resistance of the conductor is verified. The test results are shown in table 1:
TABLE-melt joint resistance test results table (unit: omega/km)
As can be seen from the table, the welding angle has a significant effect on the resistance of the molten joint, but the resistance of the molten joint and the welding angle do not have a significant regular linear relationship, and in order to find the optimal welding angle, 30 welding angles (i.e., 3 ° and 6 ° … … 90 °) were tested in the actual operation process, and the test results are shown in fig. 2.
As can be seen from fig. 2, the welding angle optimized according to the current test results is 90 °, and the resistance of the welded fusion splice at 90 ° does not satisfy the national standard, and thus it cannot be used as a conventional cable splice.
Example 8:
in order to verify the welding manner of the three cable joints, according to the above embodiments, it can be known that the resistance of the fusion joint is the smallest when the three cable joints are welded at 90 °, therefore, in this embodiment, all the three cable joints are welded at 90 °, the welding manners of exothermic welding, layered argon arc welding, layered silver brazing and brazing are respectively adopted to perform group welding, then the cable body conductor and the resistance of the fusion joint are respectively measured, and an expansion test is performed, that is, the influence of various welding manners on the resistance of the fusion joint is verified. The test results are shown in table 2:
TABLE II melt joint resistance test result table (unit: omega/km)
According to the second table, the direct current resistance of the conductor is increased to different degrees after the conductor is welded, wherein the layered silver brazing is best, the resistance of the fused joint basically meets the national standard, and the fused joint can be used as the actual operation of a cable joint. Further, the heat radiation welding effect is the worst, and the reason for this is that a large amount of impurities in the flux are introduced into the conductor after welding, resulting in an increase in resistance.
Example 9:
because the structure of the welding spot of the three resistors is complex, and the resistor at the welding spot is still slightly higher than the welding mode of the two cables, the requirement on the physical parameters of the insulating layer is relatively high in the insulation recovery process, the technical principle that the density and the tensile strength can be improved after the high-heat polyethylene is cooled is utilized, the three cooling modes of water cooling, air cooling and natural cooling are respectively used, and the influence of the three cooling modes on the density and the tensile strength of the polyethylene is explored.
The test cases are specifically as follows:
(1) experimental materials:
the method is characterized in that cross-linked polyethylene is adopted to prepare a cylindrical bar (an insulating layer in the process of simulating insulation recovery), the hot pressing temperature is 180 ℃, the prediction is carried out for 10 minutes, and the pressing (the pressure is 10Mpa) is carried out for 5 minutes.
(2) Experiment grouping
A first group: natural cooling (air slow cooling);
second group: air cooling (air quenching);
third group: water cooling (water quench).
(3) The experimental process comprises the following steps:
natural cooling (air slow cooling): keeping the pressure at 10MPa, slowly cooling the material to 25 ℃, wherein the cooling time is 3 hours;
air cooling (air quench): under the condition of keeping the pressure of 10MPa, blowing the outside of the material by wind power at the wind speed of 5-10 m/s, accelerating cooling to 25 ℃, and cooling for 2 hours;
natural cooling (air slow cooling): under the condition of keeping the pressure of 10MPa, sleeving a cooling water bag outside the material, rapidly cooling the material by using cooling water continuously flowing in the cooling water bag to 25 ℃, wherein the cooling time is 1 hour;
(4) the experimental results are as follows:
the results are shown in table three:
influence of the cooling method on physical properties of the insulating layer (crosslinked polyethylene)
| Cooling method | Density (g/cm)3) | Tensile Strength (MPa) | Tensile strain at break (%) |
| Natural cooling (air slow cooling) | 0.935 | 33.1 | 861.8 |
| Air cooling (air quench) | 0.957 | 35.9 | 908.8 |
| Water cooling (Water quench) | 0.979 | 38.4 | 967.4 |
The data in table three show that: the fact that the tensile strength, the breaking tensile strain and the density of the sample are obviously higher than those of the slowly-cooled sample in the process of rapid cooling during rapid cooling indicates that the physical properties of the insulating layer can be obviously improved by rapidly cooling the insulating layer in the process of insulation recovery, so that the insulating layer can better protect the internal cable.
While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.
Claims (10)
1. A manufacturing method of a maintenance-free high-voltage cable hot-melting T-shaped joint is characterized by comprising the following steps:
(1) and (3) cable welding: welding the wire cores of the three cables in a T shape in a silver-based brazing manner;
(2) and (3) recovering the conductor shielding: wrapping a semi-conductive hot melt tape on the surface of a cable core;
(3) and (3) insulation recovery: wrapping a main insulating layer on the outer layer of the semi-conductive hot-melt belt, heating and welding, and rapidly cooling for not more than 2 h;
(4) and (3) recovering the insulation shielding: after cooling the main insulating layer, wrapping a semi-conductive self-adhesive tape on the surface of the main insulating layer;
(5) recovering the metal shielding and the isolating sleeve: then, the copper foil tape is used for sticking and lapping the copper shielding layers at two ends;
(6) and (3) restoring the armor and the outer sheath: wrapping a first layer of waterproof composite tape, and completely overlapping the outer sheaths of the ports of the cable; the ground wire is lapped with the steel armor at each port; and wrapping a second layer of waterproof composite tape, and completely overlapping the cable port outer sheath layer.
2. The manufacturing method of the maintenance-free high-voltage cable hot melt T-shaped joint as claimed in claim 1, wherein in the step (1), the cable welding specifically comprises:
(1.1) pretreating the wire cores of three cables needing to be connected, and customizing a T-shaped graphite mold;
(1.2) placing the wire cores of the three cables in a customized T-shaped graphite die, and adding brazing filler metal with the silver content of 25-35% and brazing powder for brazing;
and (1.3) welding the wire cores by adopting a resistance welding machine in a layered welding mode, and processing the welding points of the wire cores to be smooth, free of bulges and free of burrs.
3. The manufacturing method of the maintenance-free high-voltage cable hot-melt T-shaped joint as claimed in claim 2, wherein in the step (1.1), the cable core pretreatment process comprises the following steps: and (3) eliminating a pencil stub of 50-60 mm from the main insulation of the wire core, and polishing to leak out the inner semi-conducting layer by 10-20 mm.
4. The manufacturing method of the maintenance-free high-voltage cable hot-melting T-shaped joint as claimed in claim 3, wherein in the step (1.2), before the wire cores of the three cables are placed in the customized T-shaped graphite mold, the graphite mold and the cable cores to be welded need to be heated and dehumidified respectively, the heating and dehumidifying time of the graphite is 5 minutes, and the heating and dehumidifying time of the cable cores is 1 minute.
5. The manufacturing method of the maintenance-free high-voltage cable hot-melt T-shaped joint as claimed in any one of claims 1 to 4, wherein in the step (2), the specific process of conductor shield recovery is as follows: two layers of semi-conductive hot melting tapes are wrapped on the surface of a cable core, and the inner semi-conductive layer which is ground by completely lapping the cable core is 5-8 mm.
6. The manufacturing method of the maintenance-free high-voltage cable hot melt T-shaped joint as claimed in any one of claims 1 to 4, wherein in the step (3), the main insulating layer in the insulation recovery process mainly comprises an innermost polyethylene hot melt tape, an intermediate silicone rubber self-melt tape and an outer aluminum foil tape, the winding force of the main insulating layer is 280N/cm, and no air gap is generated in the lapping process.
7. The manufacturing method of the maintenance-free hot-melting T-shaped joint of the high-voltage cable according to claim 6, wherein the wrapping thickness of the polyethylene hot-melting tape is 2-3 mm, the width of the silicon rubber self-melting tape is 100mm, and the thickness of the aluminum foil tape is 0.5 mm.
8. The method for manufacturing the maintenance-free hot-melt T-shaped joint of the high-voltage cable according to claim 6, wherein in the step (3), the temperature for heating and hot-melting the main insulating layer in the insulation recovery process is 160-200 ℃.
9. The method according to claim 6, wherein in the step (3), the insulation recovery process is performed by rapidly cooling the main insulation layer by sleeving a cooling water bag outside the main insulation layer, the cooling water bag is provided with a water inlet and a water outlet, and the main insulation layer is cooled by the cooling water flowing in the cooling water bag.
10. The manufacturing method of the maintenance-free high-voltage cable hot-melt T-shaped joint as claimed in any one of claims 1 to 4, wherein in the step (5), the thickness of the copper foil strip in the recovery process of the metal shielding and isolating sleeve is 0.5 mm.
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| CN115441295A (en) * | 2022-09-15 | 2022-12-06 | 包头钢铁（集团）有限责任公司 | Welding and hot melting manufacturing method for aluminum alloy power cable intermediate joint |
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| CN204423965U (en) * | 2014-12-26 | 2015-06-24 | 江苏双登电力科技有限公司 | A kind of multicore aluminium alloy pre-branched cable |
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