An environmentally friendly cable sheath insulated medium voltage power cable

Abstract

The present invention relates to the technical field of power cables, and proposes an environmentally friendly cable sheath insulated medium-voltage power cable, which consists of four layers, including a conductor, an insulating layer, an armor layer and a sheath layer from the inside to the outside, and the sheath layer includes the following component raw materials by weight: 60-80 parts of high-density polyethylene, 10-15 parts of fillers, 1-3 parts of antioxidants, 8-10 parts of flame retardants, 3-5 parts of plasticizers, and 1-2 parts of vulcanizers; the filler is modified silica, and the modifier of the modified silica is an aminoalkane sulfonic acid compound. Through the above technical solution, the problem of medium-voltage power cables being not environmentally friendly and having poor insulation performance in the related art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of power cables, and in particular to an environmentally friendly cable sheath insulated medium-voltage power cable. Background Art

[0002] Medium voltage power cable refers to power cable with voltage level between 1kV and 35kV, which is widely used in urban power grid construction, industrial field and large commercial facilities. Environmentally friendly cable is a cable product with less impact on the environment during production, use and disposal. With the increasing awareness of environmental protection, the use of environmentally friendly cables has become an inevitable trend. Non-environmentally friendly cables may produce a large amount of harmful substances, such as heavy metals, in the production process, which pollutes the soil and water sources; they also release toxic gases when burned, which endangers human health and the environment. In terms of insulation performance, some old insulation materials may not be able to adapt well to the electrical performance requirements under medium voltage environment. For example, under long-term voltage, some insulation materials are prone to corona discharge, local overheating and other phenomena, resulting in reduced insulation performance, thereby affecting the service life and power supply reliability of power cables. Therefore, how to improve the insulation performance of medium voltage power cables is an urgent problem to be solved. Summary of the invention

[0003] The present invention provides an environmentally friendly cable sheath insulated medium-voltage power cable, which solves the problems of the medium-voltage power cable in the related art being environmentally unfriendly and having poor insulation performance.

[0004] The technical solution of the present invention is as follows: The present invention proposes an environmentally friendly cable sheath insulated medium-voltage power cable, which comprises, from the inside to the outside, a conductor, an insulating layer, an armor layer and a sheath layer, wherein the sheath layer comprises the following component raw materials in parts by weight: 60 to 80 parts of high-density polyethylene, 10 to 15 parts of filler, 1 to 3 parts of antioxidant, 8 to 10 parts of flame retardant, 3 to 5 parts of plasticizer, and 1 to 2 parts of vulcanizer; The filler is modified silicon dioxide, and the modifier of the modified silicon dioxide is an aminoalkane sulfonic acid compound.

[0005] As a further technical solution, the conductor is made of copper.

[0006] As a further technical solution, the insulating layer is a cross-linked polyethylene insulating layer.

[0007] As a further technical solution, the material of the armor layer is steel strip.

[0008] As a further technical solution, the aminoalkane sulfonic acid compound includes one or more of 2-methyl-1-oxydodecylaminoethanesulfonic acid sodium, 2-[(1-oxooctadecyl)amino]-ethanesulfonic acid, and 4-(cyclohexylamino)-1-butanesulfonic acid.

[0009] As a further technical solution, the mass ratio of the modifier to silicon dioxide is 1~2:50.

[0010] As a further technical solution, the preparation method of the modified silicon dioxide comprises the following steps: dissolving the modifier in a solvent, adding silicon dioxide and dispersing the mixture evenly, heating and stirring the mixture for reaction, and filtering and drying the mixture to obtain the modified silicon dioxide.

[0011] As a further technical solution, the raw materials also include 10 to 15 parts of ethylene propylene rubber.

[0012] As a further technical solution, the EPDM rubber includes one or both of EPDM dipolymer rubber and EPDM terpolymer rubber.

[0013] As a further technical solution, the EPDM rubber includes one or more of ethylidene norbornene type EPDM rubber, dicyclopentadiene type EPDM rubber, and ENB-DCPD mixed type EPDM rubber.

[0014] In the present invention, the EPDM rubber is preferably EPDM rubber, and the ENB-DCPD mixed EPDM rubber is preferred. The ENB-DCPD mixed EPDM rubber has better compatibility with high-density polyethylene and modified silica, and the formed cross-linked network is more perfect, which can effectively limit the movement of molecular chains, reduce the movement channels of electrons, prevent current leakage, and help improve the insulation performance of medium-voltage power cables.

[0015] As a further technical solution, at least one of the following technical features is also included: The antioxidant includes one or more of antioxidant 264, antioxidant 3114, and antioxidant 1520; The flame retardant includes one or both of ammonium polyphosphate and triphenyl phosphate.

[0016] As a further technical solution, the plasticizer includes one or more of dioctyl phthalate, dibutyl phthalate, and diisononyl phthalate; As a further technical solution, the vulcanizing agent includes one or more of dicumyl peroxide, tert-butyl perbenzoate, and tert-butyl cumyl peroxide.

[0017] The present invention also provides a method for preparing an environmentally friendly cable sheath insulated medium-voltage power cable, comprising the following steps: S1, mixing the raw materials of the sheath layer uniformly, and extruding to obtain a sheath layer; S2. Wrap the insulation layer, armor layer and sheath layer around the conductor in sequence to obtain a cable.

[0018] As a further technical solution, the extrusion temperature is 150-180°C.

[0019] The working principle and beneficial effects of the present invention are: In the present invention, the cable sheath layer uses high-density polyethylene as a raw material, silicon dioxide is added as a filler, and an aminoalkane sulfonic acid compound is used as a modifier to modify the silicon dioxide, thereby improving the dispersibility and compatibility of silicon dioxide in the system, effectively reducing the conductive channel formed by filler agglomeration, enhancing the bonding strength between the modified silicon dioxide and the high-density polyethylene matrix, forming a tighter interface structure between the two, hindering the movement and conduction path of charges, thereby improving the insulation resistance of the sheath layer, thereby reducing the risk of leakage, and improving the insulation performance of the medium-voltage power cable. DETAILED DESCRIPTION

[0020] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] In the following examples and comparative examples: Conductor: Material is copper; Insulation layer: cross-linked polyethylene insulation layer; Armor layer: material is steel belt; High-density polyethylene: model DMDA-8007; EPDM rubber: model J-0010; Ethylene norbornene EPDM rubber: model 3090EM; Dicyclopentadiene EPDM rubber: Model 1045, manufacturer: Mitsui Chemicals, Inc.; Silicon dioxide: particle size 30nm; ENB-DCPD mixed EPDM rubber: ENB content is 7.8wt%, DCPD content is 0.7wt%.

[0022] Example 1 The preparation method of modified silicon dioxide comprises the following steps: dissolving 0.4 parts of sodium 2-methyl-1-oxydodecylaminoethane sulfonate in 100 parts of water, adding 20 parts of silicon dioxide and dispersing the mixture evenly, heating the mixture to 60° C. and stirring the mixture for 5 hours, and filtering and drying the mixture to obtain the modified silicon dioxide.

[0023] A method for preparing an environmentally friendly cable sheath insulated medium-voltage power cable comprises the following steps: S1, weigh 60 parts of high-density polyethylene, 10 parts of modified silica, 1 part of antioxidant 264, 8 parts of ammonium polyphosphate, 3 parts of dioctyl phthalate, and 1 part of dicumyl peroxide, mix them evenly, and extrude them at 150°C to obtain a sheath layer; S2. Wrap the insulation layer, armor layer and sheath layer around the conductor in sequence to obtain a cable.

[0024] Example 2 The preparation method of modified silicon dioxide comprises the following steps: dissolving 0.4 parts of sodium 2-methyl-1-oxydodecylaminoethane sulfonate in 100 parts of water, adding 20 parts of silicon dioxide and dispersing the mixture evenly, heating the mixture to 60° C. and stirring the mixture for 5 hours, and filtering and drying the mixture to obtain the modified silicon dioxide.

[0025] A method for preparing an environmentally friendly cable sheath insulated medium-voltage power cable comprises the following steps: S1, weigh 70 parts of high-density polyethylene, 12 parts of modified silica, 2 parts of antioxidant 3114, 9 parts of ammonium polyphosphate, 4 parts of dibutyl phthalate, and 1.5 parts of tert-butyl perbenzoate, mix them evenly, and extrude them at 165°C to obtain a sheath layer; S2. Wrap the insulation layer, armor layer and sheath layer around the conductor in sequence to obtain a cable.

[0026] Example 3 The preparation method of modified silicon dioxide comprises the following steps: dissolving 0.4 parts of sodium 2-methyl-1-oxydodecylaminoethane sulfonate in 100 parts of water, adding 20 parts of silicon dioxide and dispersing the mixture evenly, heating the mixture to 60° C. and stirring the mixture for 5 hours, and filtering and drying the mixture to obtain the modified silicon dioxide.

[0027] A method for preparing an environmentally friendly cable sheath insulated medium-voltage power cable comprises the following steps: S1, weigh 80 parts of high-density polyethylene, 15 parts of modified silica, 3 parts of antioxidant 1520, 10 parts of triphenyl phosphate, 5 parts of diisononyl phthalate, and 2 parts of tert-butyl isopropylbenzene peroxide, mix them evenly, and extrude them at 180°C to obtain a sheath layer; S2. Wrap the insulation layer, armor layer and sheath layer around the conductor in sequence to obtain a cable.

[0028] Example 4 Compared with Example 1, the difference in Example 4 is that the added amount of sodium 2-methyl-1-oxydodecylaminoethanesulfonate is 0.8 parts.

[0029] Example 5 Compared with Example 4, the difference of Example 5 is that sodium 2-methyl-1-oxydodecylaminoethanesulfonate is replaced by an equal amount of 2-[(1-oxooctadecyl)amino]-ethanesulfonic acid.

[0030] Example 6 Compared with Example 4, Example 6 is different in that sodium 2-methyl-1-oxydodecylaminoethanesulfonate is replaced by an equal amount of 4-(cyclohexylamino)-1-butanesulfonic acid.

[0031] Example 7 The preparation method of modified silicon dioxide comprises the following steps: dissolving 0.8 parts of sodium 2-methyl-1-oxydodecylaminoethane sulfonate in 100 parts of water, adding 20 parts of silicon dioxide and dispersing the mixture evenly, heating the mixture to 60° C. and stirring the mixture for 5 hours, and filtering and drying the mixture to obtain the modified silicon dioxide.

[0032] A method for preparing an environmentally friendly cable sheath insulated medium-voltage power cable comprises the following steps: S1, weigh 60 parts of high-density polyethylene, 10 parts of modified silica, 1 part of antioxidant 264, 8 parts of ammonium polyphosphate, 3 parts of dioctyl phthalate, 1 part of dicumyl peroxide, and 10 parts of EPDM rubber, mix them evenly, and extrude them at 150°C to obtain a sheath layer; S2. Wrap the insulation layer, armor layer and sheath layer around the conductor in sequence to obtain a cable.

[0033] Example 8 Compared with Example 7, the difference in Example 8 is that the added amount of EPDM rubber is 15 parts.

[0034] Example 9 Compared with Example 7, the difference of Example 9 is that the EPDM rubber is replaced by an equal amount of EPDM rubber, wherein the EPDM rubber is ethylidene norbornene type EPDM rubber.

[0035] Example 10 Compared with Example 9, Example 10 is different in that the ethylidene norbornene ethylene propylene diene monomer rubber is replaced with an equal amount of dicyclopentadiene ethylene propylene diene monomer rubber.

[0036] Embodiment 11 Compared with Example 9, Example 11 is different in that the ethylidene norbornene EPDM rubber is replaced with an equal amount of ENB-DCPD mixed EPDM rubber.

[0037] Comparative Example 1 Compared with Example 1, the difference in Comparative Example 1 is that the added silicon dioxide is not modified.

[0038] The sheath layer of the environmentally friendly cable sheath insulated medium voltage power cable prepared in Examples 1 to 11 and Comparative Example 1 was tested according to the following method: 1. Impulse voltage test: According to GB / T 12706.3-2020 "Rated voltage 1kV (U m =1.2kV) to 35kV (U m =40.5kV) extruded insulated power cables and accessories Part 3: Rated voltage 35kV (U m =40.5kV) cable》 to test the insulation performance of the sample.

[0039] 2. 4h voltage test (4U o ): According to GB / T 12706.3-2020 "Rated voltage 1kV (U m =1.2kV) to 35kV (U m =40.5kV) extruded insulated power cables and accessories Part 3: Rated voltage 35kV (U m =40.5kV) cable》 to test the insulation performance of the sample.

[0040] 3. Elongation at break: According to GB / T 12706.3-2020 "Rated voltage 1kV (U m =1.2kV) to 35kV (U m =40.5kV) extruded insulated power cables and accessories Part 3: Rated voltage 35kV (U m =40.5kV) cable" is used to test the elongation at break of the sample. The sheath layer is placed in an oven and aged at 100℃±2K for 3114h to obtain the elongation at break after aging.

[0041] The test results are shown in the following table: Table 1 Performance test results of the sheath layer of the environmentally friendly cable sheath insulated medium voltage power cable prepared in Examples 1 to 11 and Comparative Example 1

[0042] Compared with Comparative Example 1, Example 1 adds silica modified with an aminoalkane sulfonic acid compound. As a result, the insulation performance and elongation at break of Example 1 are better than those of Comparative Example 1, indicating that the addition of silica modified with an aminoalkane sulfonic acid compound can improve the insulation performance of the environmentally friendly cable sheath insulated medium-voltage power cable.

[0043] Compared with Example 4, Examples 5 and 6 added different types of aminoalkane sulfonic acid compounds to modify the silicon dioxide. As a result, the elongation at break of Example 4 was better than that of Examples 5 and 6, and the insulation performance remained good, indicating that when the aminoalkane sulfonic acid compound used was sodium 2-methyl-1-oxydodecylaminoethane sulfonate, the obtained environmentally friendly cable sheath insulated medium-voltage power cable had better mechanical properties and continuous and stable insulation performance.

[0044] Compared with Example 4, Examples 7 to 11 added ethylene propylene rubber. As a result, the elongation at break of Examples 7 to 11 was better than that of Example 4, and the insulation performance remained good, indicating that the addition of ethylene propylene rubber can improve the mechanical properties of environmentally friendly cable sheath insulated medium-voltage power cables.

[0045] Compared with Examples 7 and 8, Examples 9 to 11 add EPDM rubber, and the elongation at break of Examples 9 to 11 is better than that of Examples 7 and 8, indicating that the effect of EPDM rubber is better than that of EPDM rubber, and the obtained environmentally friendly cable sheath insulated medium-voltage power cable has better mechanical properties. In Examples 9 to 11, different types of EPDM rubber are added, and the elongation at break of Example 11 is better than that of Examples 9 and 10, indicating that when the added EPDM rubber is ENB-DCPD mixed EPDM rubber, the obtained shape-preserving cable sheath insulated medium-voltage power cable has better mechanical properties.

[0046] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An environmentally friendly cable sheath insulated medium voltage power cable, characterized in that: From the inside to the outside, it includes a conductor, an insulating layer, an armor layer and a sheath layer in sequence. The sheath layer includes the following component raw materials in parts by weight: 60-80 parts of high-density polyethylene, 10-15 parts of filler, 1-3 parts of antioxidant, 8-10 parts of flame retardant, 3-5 parts of plasticizer, and 1-2 parts of vulcanizer; the filler is modified silica, and the modifier of the modified silica is an aminoalkane sulfonic acid compound.

2. The environmentally friendly cable sheath insulated medium voltage power cable according to claim 1, characterized in that: The aminoalkane sulfonic acid compound includes one or more of sodium 2-methyl-1-oxydodecylaminoethanesulfonate, 2-[(1-oxooctadecyl)amino]-ethanesulfonic acid, and 4-(cyclohexylamino)-1-butanesulfonic acid.

3. The environmentally friendly cable sheath insulated medium voltage power cable according to claim 1, characterized in that: The mass ratio of the modifier to silicon dioxide is 1-2:

50.

4. The environmentally friendly cable sheath insulated medium voltage power cable according to claim 1, characterized in that: The preparation method of the modified silicon dioxide comprises the following steps: dissolving a modifier in a solvent, adding silicon dioxide and dispersing the mixture uniformly, heating and stirring the mixture for reaction, and filtering and drying the mixture to obtain the modified silicon dioxide.

5. An environmentally friendly cable sheath insulated medium voltage power cable according to any one of claims 1 to 4, characterized in that: The raw materials also include 10 to 15 parts of ethylene propylene rubber.

6. The environmentally friendly cable sheath insulated medium voltage power cable according to claim 5, characterized in that: The EPDM rubber includes one or both of EPDM rubber and EPDM rubber.

7. The environmentally friendly cable sheath insulated medium voltage power cable according to claim 6, characterized in that: When the EPDM rubber is EPDM rubber, the EPDM rubber includes one or more of ethylidene norbornene type EPDM rubber, dicyclopentadiene type EPDM rubber, and ENB-DCPD mixed type EPDM rubber.

8. The environmentally friendly cable sheath insulated medium voltage power cable according to claim 1, characterized in that: It also includes at least one of the following technical features: The antioxidant includes one or more of antioxidant 264, antioxidant 3114, and antioxidant 1520; The flame retardant includes one or both of ammonium polyphosphate and triphenyl phosphate.

9. The environmentally friendly cable sheath insulated medium voltage power cable according to claim 1, characterized in that: The plasticizer includes one or more of dioctyl phthalate, dibutyl phthalate, and diisononyl phthalate.

10. The environmentally friendly cable sheath insulated medium voltage power cable according to claim 1, characterized in that: The vulcanizing agent includes one or more of dicumyl peroxide, tert-butyl perbenzoate, and tert-butyl cumyl peroxide.

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