阅读说明：本技术 一种铝合金导体交联聚乙烯绝缘联锁铠装阻燃电力电缆 (Aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable ) 是由 余宇 田德鑫 吴俊德 申进 潘刚 吴明超 于 2021-08-18 设计创作，主要内容包括：本发明涉及一种铝合金导体交联聚乙烯绝缘联锁铠装阻燃电力电缆,属于电缆技术领域。该铝合金导体交联聚乙烯绝缘联锁铠装阻燃电力电缆,包括线芯,所述线芯包括铝合金导体,所述铝合金导体外侧挤包有绝缘层,所述线芯之间填充有填充层,所述填充层外侧设置有绕包层,所述绕包层外侧挤包有内衬层,所述内衬层外侧覆有联锁铠装层,所述联锁铠装层外侧设置有外护套。通过使用铝合金导体,与铜导体的电缆相比铝合金导体电缆具有更轻便、更柔韧、更节能、经济性超过铜缆的特点,而和铝芯电缆相比,铝合金电缆克服了铝芯电缆机械性能、弯折性能、抗蠕变性能、耐腐蚀性能不好的缺点,从而变得更安全。(The invention relates to an aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable, and belongs to the technical field of cables. This fire-retardant power cable of insulating interlocking armor of aluminum alloy conductor crosslinked polyethylene, including the sinle silk, the sinle silk includes aluminum alloy conductor, the crowded package in the aluminum alloy conductor outside has the insulating layer, it has the filling layer to fill between the sinle silk, the filling layer outside is provided with around the covering, it has the inner liner to wrap around the crowded package in the covering outside, the inner liner outside covers there is the interlocking armor, the interlocking armor outside is provided with the oversheath. Through using the aluminum alloy conductor, compared with the cable of a copper conductor, the aluminum alloy conductor cable has the characteristics of being lighter, more flexible, more energy-saving and more economical than the copper cable, and compared with the aluminum core cable, the aluminum alloy cable overcomes the defects of poor mechanical property, bending property, creep resistance and corrosion resistance of the aluminum core cable, so that the aluminum alloy conductor cable is safer.)

1. The utility model provides an aluminum alloy conductor crosslinked polyethylene insulation interlocking armor flame retardant power cable which characterized in that: the cable core comprises a cable core body, the sinle silk includes aluminum alloy conductor (1), aluminum alloy conductor (1) outside crowded package has insulating layer (2), it has filling layer (3) to fill between the sinle silk, filling layer (3) outside is provided with around covering (4), crowded package has inner liner (5) around covering (4) outside, the cover has interlocking armor (6) in the inner liner (5) outside, interlocking armor (6) outside is provided with oversheath (7).

2. The aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable according to claim 1, wherein: the outer sheath (7) comprises the following raw materials in parts by weight: 45-60 parts of polyethylene, 10.6-12.5 parts of flame retardant, 2.3-3.6 parts of antioxidant and 1.4-2.7 parts of cross-linking agent;

the outer sheath (7) is made by the following steps: adding polyethylene and a flame retardant into a double-roll open mill, milling for 5-15min at 90 ℃, carrying out melt mixing, adding an antioxidant and a crosslinking agent, mixing uniformly, and then milling for 15-25 min at 150 ℃ of 120-; and feeding the mixed materials into a double-screw extruder, extruding and granulating, heating, melting, extruding and wrapping the interlocked armor layer (6) at the outer side.

3. The aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable according to claim 2, wherein: the flame retardant is prepared by the following steps:

s1: vacuumizing the reaction kettle, introducing nitrogen, adding magnesium powder and tetrahydrofuran into the reaction kettle, adjusting the temperature to be 15-5 ℃ below zero, slowly dropwise adding (chloromethyl) trichlorosilane and tetrahydrofuran, heating to 55-65 ℃ after dropwise adding is finished, and reacting for 2.5-3 hours to obtain an intermediate A;

s2: slowly dripping an ethynyl magnesium bromide solution into the intermediate A, keeping the temperature at 0-5 ℃, heating to 65-68 ℃ after dripping, stirring and reacting for 14-18h, cooling to-10 ℃ -5 ℃, adding lithium aluminum hydride, stirring and reacting for 12-14h, finally dripping a hydrochloric acid solution, standing for 5-6h, centrifugally washing for 5-6 times, and drying to obtain an intermediate B;

s3: adding the dried intermediate B and a xylene solution into a reaction kettle, uniformly stirring, heating to 95-100 ℃ under the protection of nitrogen, adding tetramethyl divinyl disilazane, performing reflux reaction for 5-6h, heating to 125-115 ℃ for reaction for 15-18h, performing rotary evaporation on the residual solvent after the reaction is finished, and cooling to 110-115 ℃ for heat preservation for 2-2.5h to obtain an intermediate C;

s4: and adding the intermediate C into a dimethylbenzene solution, uniformly stirring, adding the modified magnesium hydroxide, stirring for reacting for 15-45min, and then putting into a vacuum drying oven for drying for 5-7h to obtain the flame retardant.

4. The aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable according to claim 3, wherein: in step S1, the ratio of the magnesium powder to the tetrahydrofuran to the amount of (chloromethyl) trichlorosilane is 1.25 g: 25mL of: 3.62 mL.

5. The aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable according to claim 3, wherein: in the step S2, the dosage ratio of the intermediate A, the ethynyl magnesium bromide solution, the lithium aluminum hydride and the hydrochloric acid solution is 2.65 g: 6mL of: 1.36 g: 30 mL.

6. The aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable according to claim 3, wherein: the intermediate B, the xylene solution and the tetramethyl divinyl disilazane in the step S3 are used in a ratio of 0.65 mol: 4.5 mL: 16 mL.

7. The aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable according to claim 3, wherein: the dosage ratio of the intermediate C, the xylene solution and the modified magnesium hydroxide in the step S4 is 2.36: 7.6 mL: 3.47 g.

8. The aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable according to claim 3, wherein: in step S4, the drying condition is that hot air with the temperature of 80-85 ℃ is used for flowing drying.

Technical Field

The invention belongs to the technical field of cables, and relates to an aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable.

Background

The aluminum alloy low-voltage power cable is mainly applied to the field of buildings, industrial engineering and new energy engineering. Compared with copper cables, the aluminum alloy cable has the characteristics of being lighter, more flexible, more energy-saving and far more economical than the copper cables. Compared with the aluminum core cable, the aluminum alloy cable overcomes the defects of poor mechanical property, bending property, creep resistance and corrosion resistance of the aluminum core cable, thereby being safer and being popular with users.

However, when the existing cable is used, the flame retardant effect of the electric wire is poor, so that the electric wire and the cable are short-circuited and fire-caught in use.

Disclosure of Invention

The invention aims to provide an aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable.

The purpose of the invention can be realized by the following technical scheme:

the utility model provides an aluminum alloy conductor crosslinked polyethylene insulation interlocking armor flame retardant power cable, includes the sinle silk, the sinle silk includes aluminum alloy conductor, the crowded package in the aluminum alloy conductor outside has the insulating layer, it has the filling layer to fill between the sinle silk, the filling layer outside is provided with around the covering, it has the inner liner to wrap around the crowded package in the covering outside, the inner liner outside covers there is the interlocking armor, the interlocking armor outside is provided with the oversheath.

Further, the outer sheath comprises the following raw materials in parts by weight: 45-60 parts of polyethylene, 10.6-12.5 parts of flame retardant, 2.3-3.6 parts of antioxidant and 1.4-2.7 parts of cross-linking agent;

the outer sheath is made by the following steps: adding polyethylene and a flame retardant into a double-roll open mill, milling for 5-15min at 90 ℃, carrying out melt mixing, adding an antioxidant and a crosslinking agent, mixing uniformly, and then milling for 15-25 min at 150 ℃ of 120-; and feeding the mixed materials into a double-screw extruder, extruding and granulating, heating, melting, extruding and wrapping the interlocked armor layer.

Further, the flame retardant is prepared by the following steps:

s1: vacuumizing the reaction kettle, introducing nitrogen, adding magnesium powder and tetrahydrofuran into the reaction kettle, adjusting the temperature to be 15-5 ℃ below zero, slowly dropwise adding (chloromethyl) trichlorosilane and tetrahydrofuran, heating to 55-65 ℃ after dropwise adding is finished, and reacting for 2.5-3 hours to obtain an intermediate A;

s2: slowly dripping an ethynyl magnesium bromide solution into the intermediate A, keeping the temperature at 0-5 ℃, heating to 65-68 ℃ after dripping, stirring for reacting for 14-18h, cooling to-10 ℃ to-5 ℃ after reacting, adding lithium aluminum hydride, stirring for reacting for 12-14h, finally dripping a hydrochloric acid solution, standing for 5-6h, centrifugally washing for 5-6 times after reacting, and drying to obtain an intermediate B;

s3: putting the intermediate B into a vacuum drying oven, vacuumizing, heating to 140 ℃, and drying for 8 hours to obtain a dried intermediate B; adding the dried intermediate B and a xylene solution into a reaction kettle, uniformly stirring, heating to 95-100 ℃ under the protection of nitrogen, adding tetramethyl divinyl disilazane, uniformly stirring, performing reflux reaction for 5-6h, heating to 125-130 ℃ for reaction for 15-18h, performing rotary evaporation to remove residual solvent after the reaction is finished, cooling to 110-115 ℃, and preserving heat for 2-2.5h to obtain an intermediate C;

s4: adding magnesium hydroxide and stearic acid into water, mixing and stirring uniformly, performing ultrasonic dispersion for 1.5-2h at room temperature, filtering, extracting with toluene for 8-10h, and drying to obtain modified magnesium hydroxide;

s5: and adding the intermediate C into a dimethylbenzene solution, uniformly stirring, adding the modified magnesium hydroxide, stirring for reacting for 15-45min, and then putting into a vacuum drying oven for drying for 5-7h to obtain the flame retardant.

Further, in step S1, the ratio of the magnesium powder, tetrahydrofuran, and (chloromethyl) trichlorosilane is 1.25 g: 25mL of: 3.62 mL.

Further, in step S2, the dosage ratio of the intermediate a, the ethynylmagnesium bromide solution, the lithium aluminum hydride and the hydrochloric acid solution is 2.65 g: 6mL of: 1.36 g: 30 mL.

Further, the intermediate B, the xylene solution and the tetramethyldivinyldisilazane in step S3 were used in a ratio of 0.65 mol: 4.5 mL: 16 mL.

Further, the intermediate C, the xylene solution and the modified magnesium hydroxide in the step S4 are used in a ratio of 2.36: 7.6 mL: 3.47 g.

Further, the drying condition in step S4 is flow drying using hot air at 80 to 85 ℃.

Further, the preparation method of the aluminum alloy conductor crosslinked polyethylene insulated interlocked armored flame-retardant power cable comprises the following steps:

the method comprises the following steps: drawing an aluminum alloy into an aluminum alloy thin wire, then stranding the aluminum alloy thin wire into a plurality of strands to form an aluminum alloy conductor, putting the aluminum alloy conductor into an annealing furnace for annealing, and extruding an insulating layer on the outer layer of the aluminum alloy conductor to prepare a wire core;

step two: and filling a filling layer between the wire cores, wrapping the lining layer, wrapping the interlocking armor layer outside the lining layer, and extruding the outer sheath outside the interlocking armor layer to obtain the aluminum alloy conductor crosslinked polyethylene insulated interlocking armored flame-retardant power cable.

Further, the insulating layer is a crosslinked polyethylene insulating layer; the filling layer is a water-blocking yarn filling layer; the inner liner is a non-woven fabric inner liner; the interlocking armor layer is an aluminum alloy belt interlocking armor layer.

The invention has the beneficial effects that:

(1) through using the aluminum alloy conductor, compared with the cable of a copper conductor, the aluminum alloy conductor cable has the characteristics of being lighter, more flexible, more energy-saving and more economical than the copper cable, and compared with the aluminum core cable, the aluminum alloy cable overcomes the defects of poor mechanical property, bending property, creep resistance and corrosion resistance of the aluminum core cable, so that the aluminum alloy conductor cable is safer.

(2) The magnesium hydroxide is grafted with an alkyl chain, and the alkyl chain segment is diffused to the interface of polyethylene and is physically wound with a macromolecular chain thereof, so that the compatibility between the magnesium hydroxide and the polyolefin is improved, and the mechanical property of the material is improved.

(3) Reacting (chloromethyl) trichlorosilane with magnesium powder to generate a synthetic intermediate A, reacting with unreacted Si-Cl and ethynyl magnesium bromide on the (chloromethyl) trichlorosilane, introducing-C ≡ CH into the intermediate A, reducing with lithium aluminum hydride to obtain an intermediate B, reacting the intermediate B with tetramethyl divinyl disilazane to obtain polycarbosilane, reacting the polycarbosilane with modified magnesium hydroxide to obtain a flame retardant, grafting the polycarbosilane into the magnesium hydroxide to enable the flame retardant to carry out ceramic reaction during combustion, transferring the polycarbosilane to the surface from the inside of a cable and enriching the polycarbosilane, decomposing the magnesium hydroxide into magnesium oxide, reacting the polycarbosilane with the magnesium oxide to generate a magnesium silicate ceramic phase, forming a compact and continuous ceramic protective layer on the surface of a carbon layer, and playing a role of a binder in a carbonization process, the polyethylene can form a carbon layer in the combustion process, so that the barrier effect of the carbon layer can be improved, and the flame retardance of the cable is improved.

(4) Although polycarbosilane can generate methane combustible gas, the combustible concentration is increased, and the combustion is intensified, a continuous and compact protective layer is formed on the surface, so that the mass transfer process between condensed opposite gas phases can be effectively blocked, a certain expansion is generated in an area in the degradation process inside the cable after decomposition products are limited by a surface compact carbon layer, the heat transfer process of gas to the inside can be effectively blocked, and the degradation of the internal material of the cable due to heat is protected.

Drawings

In order to facilitate understanding for those skilled in the art, the present invention will be further described with reference to the accompanying drawings.

FIG. 1 is a schematic structural diagram of an aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable according to the invention;

in the figure: 1. an aluminum alloy conductor; 2. an insulating layer; 3. a filling layer; 4. wrapping a covering; 5. an inner liner layer; 6. an interlocking armor layer; 7. an outer sheath.

Detailed Description

To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description of the embodiments, structures, features and effects according to the present invention will be made with reference to the accompanying drawings and preferred embodiments.

Referring to fig. 1, the aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable comprises a cable core, wherein the cable core comprises an aluminum alloy conductor 1, an insulating layer 2 is extruded on the outer side of the aluminum alloy conductor 1, filling layers 3 are filled among the cable cores, a wrapping layer 4 is arranged on the outer side of each filling layer 3, an inner liner 5 is extruded on the outer side of each wrapping layer 4, an interlocking armor layer 6 covers the outer side of each inner liner 5, and an outer sheath 7 is arranged on the outer side of each interlocking armor layer 6.

Example 1

Preparing a flame retardant:

s1: vacuumizing the reaction kettle, introducing nitrogen, adding magnesium powder and tetrahydrofuran into the reaction kettle, adjusting the temperature to-15 ℃, then slowly dropwise adding (chloromethyl) trichlorosilane and tetrahydrofuran, and controlling the dosage ratio of the magnesium powder, the tetrahydrofuran and the (chloromethyl) trichlorosilane to be 1.25 g: 25mL of: 3.62mL, after the dropwise addition, heating to 55 ℃, and reacting for 2.5h to obtain an intermediate A;

s2: slowly dropwise adding an ethynyl magnesium bromide solution into the intermediate A, keeping the temperature at 0-5 ℃, heating to 65-68 ℃ after dropwise adding, stirring for reacting for 14h, cooling to-10 ℃ after the reaction is finished, adding lithium aluminum hydride, stirring for reacting for 12h, and finally dropwise adding a hydrochloric acid solution, wherein the dosage ratio of the intermediate A, the ethynyl magnesium bromide solution, the lithium aluminum hydride and the hydrochloric acid solution is controlled to be 2.65 g: 6mL of: 1.36 g: standing for 5 hours by 30mL, centrifugally washing for 5 times after the reaction is finished, and drying to obtain an intermediate B;

s3: putting the intermediate B into a vacuum drying oven, vacuumizing, heating to 140 ℃, and drying for 8 hours to obtain a dried intermediate B; adding the dried intermediate B and the xylene solution into a reaction kettle, uniformly stirring, heating to 95 ℃ under the protection of nitrogen, adding tetramethyl divinyl disilazane, and controlling the dosage ratio of the intermediate B, the xylene solution and the tetramethyl divinyl disilazane to be 0.65 mol: 4.5 mL: 16mL, stirring uniformly, performing reflux reaction for 5h, heating to 125 ℃ for reaction for 15h, performing rotary evaporation on residual solvent after the reaction is finished, cooling to 110 ℃, and keeping the temperature for 2h to obtain an intermediate C;

s4: adding magnesium hydroxide and stearic acid into water, mixing and stirring uniformly, performing ultrasonic dispersion for 1.5-2h at room temperature, filtering, extracting with toluene for 8h, and drying to obtain modified magnesium hydroxide;

s5: adding the intermediate C into a dimethylbenzene solution, uniformly stirring, adding modified magnesium hydroxide, and controlling the dosage ratio of the intermediate C to the dimethylbenzene solution to be 2.36: 7.6 mL: 3.47g, stirring and reacting for 15min, and then putting into a vacuum drying oven to dry for 5h to obtain the flame retardant.

Example 2

Preparing a flame retardant:

s1: vacuumizing the reaction kettle, introducing nitrogen, adding magnesium powder and tetrahydrofuran into the reaction kettle, adjusting the temperature to minus 10 ℃, then slowly dropwise adding (chloromethyl) trichlorosilane and tetrahydrofuran, and controlling the dosage ratio of the magnesium powder, the tetrahydrofuran and the (chloromethyl) trichlorosilane to be 1.25 g: 25mL of: 3.62mL, after the dropwise addition, heating to 60 ℃, and reacting for 2.7h to obtain an intermediate A;

s2: slowly dropwise adding an ethynyl magnesium bromide solution into the intermediate A, keeping the temperature at 3 ℃, heating to 66.5 ℃ after dropwise adding, stirring for reacting for 16h, cooling to minus 7 ℃ after the reaction is finished, adding lithium aluminum hydride, stirring for reacting for 13h, and finally dropwise adding a hydrochloric acid solution, wherein the dosage ratio of the intermediate A, the ethynyl magnesium bromide solution, the lithium aluminum hydride and the hydrochloric acid solution is controlled to be 2.65 g: 6mL of: 1.36 g: standing for 5-6h after 30mL, centrifugally washing for 5 times after the reaction is finished, and drying to obtain an intermediate B;

s3: putting the intermediate B into a vacuum drying oven, vacuumizing, heating to 140 ℃, and drying for 8 hours to obtain a dried intermediate B; adding the dried intermediate B and the xylene solution into a reaction kettle, uniformly stirring, heating to 97 ℃ under the protection of nitrogen, adding tetramethyl divinyl disilazane, and controlling the dosage ratio of the intermediate B, the xylene solution and the tetramethyl divinyl disilazane to be 0.65 mol: 4.5 mL: 16mL, stirring uniformly, performing reflux reaction for 5-6h, heating to 128 ℃ for 17h, performing rotary evaporation on residual solvent after the reaction is finished, cooling to 113 ℃, and keeping the temperature for 2.3h to obtain an intermediate C;

s4: adding magnesium hydroxide and stearic acid into water, mixing and stirring uniformly, performing ultrasonic dispersion for 1.5-2h at room temperature, filtering, extracting for 9h by using toluene, and drying to obtain modified magnesium hydroxide;

s5: adding the intermediate C into a dimethylbenzene solution, uniformly stirring, adding modified magnesium hydroxide, and controlling the dosage ratio of the intermediate C to the dimethylbenzene solution to be 2.36: 7.6 mL: 3.47g, stirring and reacting for 30min, and then putting into a vacuum drying oven to dry for 6h to obtain the flame retardant.

Example 3

Preparing a flame retardant:

s1: vacuumizing the reaction kettle, introducing nitrogen, adding magnesium powder and tetrahydrofuran into the reaction kettle, adjusting the temperature to-5 ℃, then slowly dropwise adding (chloromethyl) trichlorosilane and tetrahydrofuran, and controlling the dosage ratio of the magnesium powder, the tetrahydrofuran and the (chloromethyl) trichlorosilane to be 1.25 g: 25mL of: 3.62mL, after the dropwise addition, heating to 65 ℃, and reacting for 3 hours to obtain an intermediate A;

s2: slowly dropwise adding an ethynyl magnesium bromide solution into the intermediate A, keeping the temperature at 5 ℃, heating to 68 ℃ after dropwise adding, stirring for reacting for 18 hours, cooling to-5 ℃ after the reaction is finished, adding lithium aluminum hydride, stirring for reacting for 14 hours, and finally dropwise adding a hydrochloric acid solution, wherein the dosage ratio of the intermediate A, the ethynyl magnesium bromide solution, the lithium aluminum hydride and the hydrochloric acid solution is controlled to be 2.65 g: 6mL of: 1.36 g: standing for 6 hours by 30mL, centrifugally washing for 6 times after the reaction is finished, and drying to obtain an intermediate B;

s3: putting the intermediate B into a vacuum drying oven, vacuumizing, heating to 140 ℃, and drying for 8 hours to obtain a dried intermediate B; adding the dried intermediate B and the xylene solution into a reaction kettle, uniformly stirring, heating to 100 ℃ under the protection of nitrogen, adding tetramethyl divinyl disilazane, and controlling the dosage ratio of the intermediate B, the xylene solution and the tetramethyl divinyl disilazane to be 0.65 mol: 4.5 mL: 16mL, stirring uniformly, performing reflux reaction for 6h, heating to 130 ℃ for 18h, performing rotary evaporation to remove residual solvent after the reaction is finished, cooling to 115 ℃, and keeping the temperature for 2.5h to obtain an intermediate C;

s4: adding magnesium hydroxide and stearic acid into water, mixing and stirring uniformly, performing ultrasonic dispersion for 1.5-2h at room temperature, filtering, extracting with toluene for 10h, and drying to obtain modified magnesium hydroxide;

s5: adding the intermediate C into a dimethylbenzene solution, uniformly stirring, adding modified magnesium hydroxide, and controlling the dosage ratio of the intermediate C to the dimethylbenzene solution to be 2.36: 7.6 mL: 3.47g, stirring and reacting for 45min, and then putting into a vacuum drying oven for drying for 7h to obtain the flame retardant.

Example 4

Preparing an outer sheath:

the outer sheath 7 comprises the following raw materials in parts by weight: 45 parts of polyethylene, 10.6 parts of flame retardant prepared in example 2, 2.3 parts of antioxidant and 1.4 parts of crosslinking agent;

the outer sheath 7 is made by the following steps: adding polyethylene and a flame retardant into a double-roll open mill, open milling for 5min at 90 ℃, carrying out melt mixing, adding an antioxidant and a crosslinking agent, mixing uniformly, and then mixing for 15min at 120 ℃ to obtain a mixed material; and feeding the mixed materials into a double-screw extruder, extruding and granulating, heating, melting, extruding and wrapping the interlocking armor layer 6.

Example 5

Preparing an outer sheath:

the outer sheath 7 comprises the following raw materials in parts by weight: 55 parts of polyethylene, 11.5 parts of the flame retardant prepared in example 2, 3 parts of antioxidant and 2 parts of crosslinking agent;

the outer sheath 7 is made by the following steps: adding polyethylene and a flame retardant into a double-roll open mill, milling for 10min at 90 ℃, carrying out melt mixing, adding an antioxidant and a crosslinking agent, mixing uniformly, and then mixing for 20 min at 130 ℃ to obtain a mixed material; and feeding the mixed materials into a double-screw extruder, extruding and granulating, heating, melting, extruding and wrapping the interlocking armor layer 6.

Example 6

Preparing an outer sheath:

the outer sheath 7 comprises the following raw materials in parts by weight: 60 parts of polyethylene, 12.5 parts of flame retardant prepared in example 2, 3.6 parts of antioxidant and 2.7 parts of crosslinking agent;

the outer sheath 7 is made by the following steps: adding polyethylene and a flame retardant into a double-roll open mill, milling for 15min at 90 ℃, carrying out melt mixing, adding an antioxidant and a crosslinking agent, mixing uniformly, and then mixing for 25 min at 150 ℃ to obtain a mixed material; and feeding the mixed materials into a double-screw extruder, extruding and granulating, heating, melting, extruding and wrapping the interlocking armor layer 6.

Example 7

The preparation method of the aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cable comprises the following steps:

the method comprises the following steps: drawing an aluminum alloy into an aluminum alloy thin wire, then stranding the aluminum alloy thin wire to form an aluminum alloy conductor 1, putting the aluminum alloy conductor 1 into an annealing furnace for annealing, and extruding an insulating layer 2 on the outer layer of the aluminum alloy conductor 1 to prepare a wire core;

step two: and filling a filling layer 3 between the wire cores, winding and wrapping the lining layer 5, wrapping the interlocking armor layer 6 outside the lining layer 5, and extruding the outer sheath 7 prepared in the embodiment 5 outside the interlocking armor layer 6 to obtain the aluminum alloy conductor 1 crosslinked polyethylene insulation interlocking armored flame-retardant power cable.

The aluminum alloy conductor crosslinked polyethylene insulation interlocking armored flame-retardant power cables prepared in the examples 5 to 7 and the comparative example are tested for flame-retardant performance by using a ZLT-UL94 vertical combustion tester according to a vertical combustion test standard UL94-2015, and the tensile strength and the elongation at break of the cable are detected according to GB/T1040, and the results are shown in the following table:

as can be seen from the table, the cable prepared by the above examples has excellent flame retardant property and good mechanical property.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.