Crosslinked polyethylene insulated power cable

Abstract

The invention relates to the technical field of cables, and provides a cross-linked polyethylene insulated power cable which sequentially comprises a wire, a cross-linked polyethylene insulating layer, a shielding layer, an armor layer and a sheath layer from inside to outside. The wire comprises a reinforcing core and a conductive aluminum wire layer, and the conductive aluminum wire layer is formed by twisting a plurality of conductors. The cross-linked polyethylene insulating layer comprises the following raw material components in parts by weight: 70-90 parts of low-density polyethylene, 8-12 parts of a plasticizer, 2-4 parts of a cross-linking agent, 15-20 parts of a flame retardant, 8-10 parts of a reinforcing agent, 1-3 parts of a lubricant and 0.5-1 part of an antioxidant. According to the technical scheme, the problem of low flame retardance of the crosslinked polyethylene insulated power cable in the related technology is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cable, in particular, to a kind of crosslinked polyethylene insulated power cable. BACKGROUND

[0002] Crosslinked polyethylene insulated power cable is a kind of power cable using crosslinked polyethylene as insulation layer, mainly applied to distribution network or industrial device fixed laying scene, both kinds of scenes have high correlation, power cable once fires, not only will directly damage equipment, but also cause power interruption, personnel casualty problem.Therefore, it is necessary to improve the flame retardancy of power cable, improve the safety of power cable in use.

[0003] In order to improve the flame retardancy of power cable, the prior art often increases the proportion of flame retardant in the raw material of insulation layer to increase the flame retardancy of insulation layer, and the flame retardant is mostly aluminum hydroxide and magnesium hydroxide.However, magnesium hydroxide and aluminum hydroxide have poor compatibility with the base material of insulation layer, and are not uniformly dispersed, which can not improve the flame retardancy of insulation layer well. SUMMARY

[0004] The present application provides a kind of crosslinked polyethylene insulated power cable, solve the problem of low flame retardancy of crosslinked polyethylene insulated cable in the related art.

[0005] The technical scheme of the present application is as follows: The present application provides a kind of crosslinked polyethylene insulated power cable, from inside to outside, it includes wire, crosslinked polyethylene insulation layer, shielding layer, armored layer, sheath layer;The wire includes reinforcing core and conductive aluminum wire layer, the conductive aluminum wire layer is twisted by multiple conductors;The raw material of the crosslinked polyethylene insulation layer includes the following components by weight: low density polyethylene 70~90 parts, plasticizer 8~12 parts, crosslinking agent 2~4 parts, flame retardant 15~20 parts, reinforcing agent 8~10 parts, lubricant 1~3 parts, antioxidant 0.5~1 part.

[0006] As a further technical scheme, the sheath layer is a polyethylene sheath layer.

[0007] As a further technical scheme, the gap between the crosslinked polyethylene insulation layer and the shielding layer is filled with a filling material.

[0008] As a further technical scheme, the armored layer is obtained by wrapping a steel belt outside the shielding layer.

[0009] As a further technical scheme, the material of the shielding layer is copper wire.

[0010] As a further technical scheme, the raw material of the flame retardant includes aluminum hydroxide, magnesium hydroxide and p-chloroacetanilide.

[0011] In the present application, the addition of p-chloroacetanilide in the raw material of the cross-linked polyethylene insulation power cable insulation layer flame retardant not only improves the flame retardant performance of the insulation layer, but also improves the mechanical properties of the insulation layer, thereby improving the flame retardation of the cross-linked polyethylene insulation power cable and prolonging the service life of the cross-linked polyethylene insulation power cable.

[0012] As a further technical solution, the mass ratio of aluminum hydroxide, magnesium hydroxide and p-chloroacetanilide is 50:50:6-10.

[0013] As a further technical solution, the flame retardant in the magnesium hydroxide is modified magnesium hydroxide, and the modified magnesium hydroxide is obtained by modifying magnesium hydroxide with (aminoethyl aminomethyl) phenethyl trimethoxysilane and 2,4-dichlorobenzoic acid.

[0014] As a further technical solution, the mass of (aminoethyl aminomethyl) phenethyl trimethoxysilane and 2,4-dichlorobenzoic acid is 4%-6% of the mass of magnesium hydroxide.

[0015] As a further technical solution, the mass ratio of (aminoethyl aminomethyl) phenethyl trimethoxysilane and dimethyldimethoxysilane is 5:1-2.

[0016] As a further technical solution, the preparation method of the modified magnesium hydroxide comprises the following steps: After (aminoethyl aminomethyl) phenethyl trimethoxysilane is added to the ethanol aqueous solution and mixed uniformly, magnesium hydroxide is added and mixed, then 2,4-dichlorobenzoic acid is added and mixed, and then dried to obtain modified magnesium hydroxide.

[0017] As a further technical solution, the mass-volume ratio of magnesium hydroxide and ethanol aqueous solution is 1g:8mL.

[0018] As a further technical solution, the ethanol aqueous solution is composed of anhydrous ethanol and water in a volume ratio of 3:1.

[0019] As a further technical solution, the plasticizer includes one or both of dibutyl phthalate and dioctyl phthalate.

[0020] As a further technical solution, the cross-linking agent includes dicumyl peroxide.

[0021] As a further technical solution, the reinforcing agent includes one or more of kaolin, white carbon black and talc powder.

[0022] As a further technical solution, the lubricant includes one or both of stearic acid and calcium stearate.

[0023] As a further technical solution, the antioxidant includes one or more of antioxidant 1010, antioxidant 168, and antioxidant 1076.

[0024] The working principle and beneficial effects of the present application are as follows: In the present application, the crosslinked polyethylene insulated power cable sequentially comprises a conductor, a crosslinked polyethylene insulation layer, a shielding layer, an armored layer, and a sheath layer from inside to outside, wherein the shielding layer can resist external electromagnetic interference to ensure stable transmission of current; the armored layer acts as a physical barrier to resist direct burning of the insulation layer by external flames and slow down the pyrolysis speed of the insulation layer; the outer sheath layer as the outermost layer of the power cable can resist physical damage to ensure the structural integrity of the cable; and the addition of the flame retardant in the polyethylene insulation layer can better improve the flame retardancy of the crosslinked polyethylene insulated power cable. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0026] In the following examples and comparative examples: The conductor is composed of a reinforcing core and 13 aluminum wires twisted outside the reinforcing core, and the reinforcing core is composed of 7 aluminum wires; Low-density polyethylene: model D110, purchased from Shanghai Petrochemical; Talc: particle size 800 mesh; Magnesium hydroxide: particle size 1250 mesh; Aluminum hydroxide: particle size 1250 mesh.

[0027] Example 1 A preparation method of a crosslinked polyethylene insulated power cable, comprising the following steps: S1, uniformly mix 70 parts of low-density polyethylene, 8 parts of dibutyl phthalate, 15 parts of a flame retardant, 8 parts of talc, 1 part of stearic acid, and 0.5 parts of antioxidant 1010, then add 2 parts of dicumyl peroxide and mix again, extrude and coat on the outside of the conductor, crosslink at 165℃ and 15MPa for 25min to form a crosslinked polyethylene insulation layer; wherein the flame retardant is composed of magnesium hydroxide and aluminum hydroxide in a mass ratio of 1:1; S2, spiral wrap copper wire on the outside of the crosslinked polyethylene insulation layer to form a shielding layer; wherein the gap between the crosslinked polyethylene insulation layer and the shielding layer is filled with a filling material (fine sand); S3, wrap steel tape on the outside of the shielding layer to form an armored layer; S4, extruding polyethylene material outside the armored layer to form a sheath layer, to obtain the crosslinked polyethylene insulated power cable.

[0028] Example 2 A preparation method of a crosslinked polyethylene insulated power cable, comprising the following steps: S1, mixing low density polyethylene 80 parts, dioctyl phthalate 9 parts, flame retardant 18 parts, talcum powder 9 parts, stearic acid 2 parts, antioxidant 1010 0.8 parts uniformly, then adding dicumyl peroxide 3 parts and mixing again, then extruding outside the conductor, crosslinking at 165℃, 15MPa for 25min to form a crosslinked polyethylene insulation layer; wherein the flame retardant is composed of magnesium hydroxide and aluminum hydroxide with a mass ratio of 1:1; S2, spirally winding copper wire outside the crosslinked polyethylene insulation layer to form a shielding layer; wherein the gap between the crosslinked polyethylene insulation layer and the shielding layer is filled with a filling material (fine sand); S3, wrapping steel tape outside the shielding layer to form an armored layer; S4, extruding polyethylene material outside the armored layer to form a sheath layer, to obtain the crosslinked polyethylene insulated power cable.

[0029] Example 3 A preparation method of a crosslinked polyethylene insulated power cable, comprising the following steps: S1, mixing low density polyethylene 90 parts, dioctyl phthalate 12 parts, flame retardant 20 parts, talcum powder 10 parts, stearic acid 3 parts, antioxidant 1010 1 part uniformly, then adding dicumyl peroxide 4 parts and mixing again, then extruding outside the conductor, crosslinking at 165℃, 15MPa for 25min to form a crosslinked polyethylene insulation layer; wherein the flame retardant is composed of magnesium hydroxide and aluminum hydroxide with a mass ratio of 1:1; S2, spirally winding copper wire outside the crosslinked polyethylene insulation layer to form a shielding layer; wherein the gap between the crosslinked polyethylene insulation layer and the shielding layer is filled with a filling material (fine sand); S3, wrapping steel tape outside the shielding layer to form an armored layer; S4, extruding polyethylene material outside the armored layer to form a sheath layer, to obtain the crosslinked polyethylene insulated power cable.

[0030] Example 4 Compared with example 1, the flame retardant in this embodiment is composed of aluminum hydroxide, magnesium hydroxide and p-chloroacetanilide with a mass ratio of 50:50:6.

[0031] Example 5 Compared with example 1, the flame retardant in this embodiment is composed of aluminum hydroxide, magnesium hydroxide and p-chloroacetanilide with a mass ratio of 50:50:8.

[0032] Example 6 Compared with Example 1, the flame retardant in this example is composed of aluminum hydroxide, magnesium hydroxide and p-chloroacetanilide with a mass ratio of 50:50:10.

[0033] Example 7 Compared with Example 5, the magnesium hydroxide in the flame retardant in this example is modified magnesium hydroxide, and the preparation method of the modified magnesium hydroxide comprises the following steps: (aminoethyl aminomethyl) phenethyl trimethoxysilane is added to an aqueous ethanol solution (composed of anhydrous ethanol and water with a volume ratio of 3:1) and mixed uniformly, then magnesium hydroxide is added and mixed at 40℃ for 3h, and then dried to obtain modified magnesium hydroxide; wherein the mass of (aminoethyl aminomethyl) phenethyl trimethoxysilane is 5% of the mass of magnesium hydroxide, and the mass-volume ratio of magnesium hydroxide to the aqueous ethanol solution is 1g:8mL.

[0034] Example 8 Compared with Example 5, the magnesium hydroxide in the flame retardant in this example is modified magnesium hydroxide, and the preparation method of the modified magnesium hydroxide comprises the following steps: (aminoethyl aminomethyl) phenethyl trimethoxysilane is added to an aqueous ethanol solution (composed of anhydrous ethanol and water with a volume ratio of 3:1) and mixed uniformly, then magnesium hydroxide is added and mixed at 40℃ for 1.5h, then 2,4-dichlorobenzoic acid is added and mixed at 40℃ for 1.5h, and then dried to obtain modified magnesium hydroxide; wherein the mass of (aminoethyl aminomethyl) phenethyl trimethoxysilane and 2,4-dichlorobenzoic acid is 5% of the mass of magnesium hydroxide, and the mass ratio of (aminoethyl aminomethyl) phenethyl trimethoxysilane to 2,4-dichlorobenzoic acid is 5:1.5; the mass-volume ratio of magnesium hydroxide to the aqueous ethanol solution is 1g:8mL.

[0035] Example 9 Compared with Example 5, the magnesium hydroxide in the flame retardant in this example is modified magnesium hydroxide, and the preparation method of the modified magnesium hydroxide comprises the following steps: 2,4-dichlorobenzoic acid is added to an aqueous ethanol solution (composed of anhydrous ethanol and water with a volume ratio of 3:1) and mixed uniformly, then magnesium hydroxide is added and mixed at 40℃ for 1.5h, then (aminoethyl aminomethyl) phenethyl trimethoxysilane is added and mixed at 40℃ for 1.5h, and then dried to obtain modified magnesium hydroxide; wherein the mass of (aminoethyl aminomethyl) phenethyl trimethoxysilane and 2,4-dichlorobenzoic acid is 5% of the mass of magnesium hydroxide, and the mass ratio of (aminoethyl aminomethyl) phenethyl trimethoxysilane to 2,4-dichlorobenzoic acid is 5:1.5; the mass-volume ratio of magnesium hydroxide to the aqueous ethanol solution is 1g:8mL.

[0036] Example 10 Compared with Example 5, in the present example, the magnesium hydroxide in the flame retardant is modified magnesium hydroxide, and the preparation method of the modified magnesium hydroxide comprises the following steps: 2,4-dichlorobenzenacetic acid is added into an ethanol aqueous solution (consisting of anhydrous ethanol and water in a volume ratio of 3:1) and mixed uniformly, then magnesium hydroxide is added and mixed at 40℃ for 3h, and then dried to obtain the modified magnesium hydroxide; wherein the mass of 2,4-dichlorobenzenacetic acid is 5% of the mass of magnesium hydroxide, and the mass-volume ratio of magnesium hydroxide to the ethanol aqueous solution is 1g:8mL.

[0037] Experimental example The flame retardancy and tensile strength of the crosslinked polyethylene insulation layer in Examples 1-10 were determined, and the determination method was as follows: (1) Flame retardancy: the oxygen index was tested according to GB / T 2406.2-2009 "Determination of the flammability of plastics - Part 2: test method in room temperature", wherein the sample type was I, and the ignition method was A; (2) Tensile strength: the tensile strength was tested according to the method in GB / T 2951.11-2008 "Cables and optical fibers - Determination of the mechanical and dimensional properties of the insulation and sheaths - Part 11: general test methods - Measurement of thickness and outer dimensions - Mechanical property tests", and the sample to be tested was a dumbbell test piece with a thickness of 3mm; The determination results are shown in Tables 1-2.

[0038] Table 1 Determination results of the flame retardancy of the crosslinked polyethylene insulation layer in Examples 1-8

[0039] Compared with Example 1, the flame retardant in Example 4 is composed of aluminum hydroxide, magnesium hydroxide and p-chloroacetanilide, and the results show that the flame retardancy of the crosslinked polyethylene insulation layer in Example 4 is higher than that in Example 1, indicating that the addition of p-chloroacetanilide in the raw materials of the flame retardant can improve the flame retardancy of the crosslinked polyethylene insulation layer.

[0040] Table 2 Determination results of the tensile strength of the crosslinked polyethylene insulation layer in Examples 1, 4-10

[0041] Compared with Example 1, the flame retardant in Example 4 is composed of aluminum hydroxide, magnesium hydroxide and p-chloroacetanilide, and the results show that the tensile strength of the crosslinked polyethylene insulation layer in Example 4 is higher than that in Example 1, indicating that the addition of p-chloroacetanilide in the flame retardant can also improve the tensile strength of the crosslinked polyethylene insulation layer.

[0042] The above is only a preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A crosslinked polyethylene insulated power cable, characterized in that, From inside to outside, the cable comprises a conductor, a cross-linked polyethylene insulation layer, a shielding layer, an armor layer and a sheath layer; the conductor comprises a reinforcing core and a conductive aluminum wire layer, the conductive aluminum wire layer is twisted by a plurality of conductors; the raw material of the cross-linked polyethylene insulation layer comprises the following components in parts by weight: low-density polyethylene 70-90 parts, plasticizer 8-12 parts, cross-linking agent 2-4 parts, flame retardant 15-20 parts, reinforcing agent 8-10 parts, lubricant 1-3 parts, antioxidant 0.5-1 part.

2. A crosslinked polyethylene insulated power cable according to claim 1, characterized in that The sheath layer is a polyethylene sheath layer.

3. A crosslinked polyethylene insulated power cable according to claim 1, characterized in that, The gap between the cross-linked polyethylene insulation layer and the shielding layer is filled by a filling material.

4. A crosslinked polyethylene insulated power cable according to claim 1, characterized in that The armor layer is obtained by wrapping a steel belt outside the shielding layer.

5. A crosslinked polyethylene insulated power cable according to claim 1, characterized in that, The material of the shielding layer is copper wire.

6. A crosslinked polyethylene insulated power cable according to claim 1, characterized in that The raw material of the flame retardant comprises aluminum hydroxide, magnesium hydroxide and p-chloroacetanilide.

7. A crosslinked polyethylene insulated power cable according to claim 6, characterized in that The mass ratio of the aluminum hydroxide, the magnesium hydroxide and the p-chloroacetanilide is 50:50:6-10.

8. A crosslinked polyethylene insulated power cable according to claim 1, characterized in that The magnesium hydroxide in the flame retardant is modified magnesium hydroxide, and the modified magnesium hydroxide is obtained by modifying the magnesium hydroxide with (aminoethyl aminomethyl) phenethyl trimethoxysilane and 2,4-dichlorobenzoic acid.

9. A crosslinked polyethylene insulated power cable according to claim 8, characterized in that The mass of the (aminoethyl aminomethyl) phenethyl trimethoxysilane and the 2,4-dichlorobenzoic acid is 4%-6% of the mass of the magnesium hydroxide.

10. A crosslinked polyethylene insulated power cable according to claim 8, characterized in that The mass ratio of the (aminoethyl aminomethyl) phenethyl trimethoxysilane and dimethyldimethoxysilane is 5:1-2.

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