Anticorrosive grease coated steel-cored aluminum stranded wire and preparation method thereof

Abstract

The application relates to the technical field of cables, and discloses a kind of anticorrosive grease coated steel-cored aluminum stranded wire and a preparation method thereof.A kind of anticorrosive grease coated steel-cored aluminum stranded wire, comprising a steel core, an aluminum stranded wire layer twisted outside the steel core and an anticorrosive coating;The aluminum stranded wire layer is twisted by aluminum wire, and the outer periphery of the aluminum stranded wire layer is coated with an anticorrosive coating;The raw materials of the anticorrosive coating include the following components by weight: 75-85 parts of base oil, 6-10 parts of isocyanate, 5-10 parts of organic amine, 0.5-1.5 parts of fatty alcohol, 1.5-3 parts of anticorrosive additive;The organic amine includes p-phenylenediamine and straight-chain aliphatic diamine with a carbon chain length of C6-C12 in a mass ratio of 1:2-3.Through the above technical solution, the problem of low salt mist resistance of the steel-cored aluminum stranded wire in the related art is solved.

Description

Technical Field

[0001] This invention relates to the field of cable technology, specifically to a steel-cored aluminum stranded wire coated with anti-corrosion grease and its preparation method. Background Technology

[0002] Steel-cored aluminum stranded wire is the core load-bearing and conductive component of overhead transmission lines, widely used in power grid transmission, long-span crossings across rivers, coastal ports, and industrial corrosive areas. Steel-cored aluminum stranded wire consists of a galvanized steel core and an outer layer of aluminum strands. The potential difference between the steel and aluminum metals makes them highly susceptible to galvanic corrosion in outdoor environments with high humidity, salt spray, condensation, and industrial pollution. In particular, the high concentration of chloride ions in coastal areas has a strong penetrating and activating corrosion ability, easily inducing pitting corrosion in the aluminum layer and rusting in the steel core. This leads to conductor cross-sectional loss, decreased mechanical strength, and increased contact resistance, severely affecting the operational safety and service life of the transmission line.

[0003] Currently, the industry generally uses anti-corrosion grease to coat the surface of steel-cored aluminum stranded wire to achieve protection. The grease coating relies on the physical barrier effect to isolate water vapor, oxygen and salt spray media, and delay metal corrosion failure. However, in actual applications, its salt spray resistance performance cannot meet the high requirements of use.

[0004] Therefore, it is necessary to develop anti-corrosion grease-coated aluminum stranded wire with high salt spray resistance to extend operational safety and service life. Summary of the Invention

[0005] This invention proposes a corrosion-resistant grease-coated steel-cored aluminum stranded wire and its preparation method to solve or alleviate at least one of the above-mentioned problems.

[0006] The technical solution of the present invention is as follows: This invention proposes a corrosion-resistant grease-coated steel-core aluminum stranded wire, comprising a steel core, an aluminum stranded wire layer stranded around the steel core, and a corrosion-resistant coating; the aluminum stranded wire layer is formed by stranding aluminum wires, and the outer periphery of the aluminum stranded wire layer is coated with the corrosion-resistant coating; the raw materials of the corrosion-resistant coating include the following components in parts by weight: 75-85 parts base oil, 6-10 parts isocyanate, 5-10 parts organic amine, 0.5-1.5 parts fatty alcohol, and 1.5-3 parts corrosion-resistant additive; the organic amine includes p-phenylenediamine in a mass ratio of 1:2-3 and straight-chain aliphatic diamine with a carbon chain length of C6-C12.

[0007] Preferably, the straight-chain aliphatic diamine with a carbon chain length of C6 to C12 includes 1,6-hexanediamine and 1,12-dodecanediamine in a mass ratio of 1:1 to 2.

[0008] Preferably, the corrosion inhibitor includes modified silica, the raw materials of which include silica and a modifier, and the modifier includes silane coupling agent KH-550 and silane coupling agent KH-792 in a mass ratio of 5:1~2.

[0009] Preferably, the amount of the modifier added is 4% to 6% of the mass of silicon dioxide.

[0010] Preferably, the average particle size of the silicon dioxide is 20~40nm.

[0011] Preferably, the method for preparing the modified silica includes the following steps: dispersing the modifier in water, then adding silica and mixing, followed by drying to obtain the modified silica.

[0012] Preferably, the base oil comprises mineral oil.

[0013] Preferably, the isocyanate includes one or more of toluene diisocyanate, dimethyl diphenylmethane diisocyanate, and diphenylmethane diisocyanate.

[0014] Preferably, the fatty alcohol includes palmitol.

[0015] This invention also proposes a method for preparing anti-corrosion grease-coated steel-cored aluminum stranded wire, which includes the following steps: S1. Twist aluminum wires around a steel core to form an aluminum stranded wire layer; S2. After mixing the raw materials of the anti-corrosion coating, apply it to the outer surface of the aluminum stranded wire layer and cure it to form an anti-corrosion coating, thus obtaining anti-corrosion grease coated steel core aluminum stranded wire.

[0016] The beneficial effects of this invention are as follows: This invention employs a composite organic amine system, combining p-phenylenediamine with a linear aliphatic diamine with a carbon chain length of C6-C12, which crosslinks with isocyanate to form a dense and stable polyurea network. This effectively solves the problems of numerous structural defects and easy penetration of salt spray media in traditional anti-corrosion oils, significantly improving the coating's salt spray resistance. Rigid p-phenylenediamine increases the coating's crosslinking density and structural rigidity, effectively blocking chloride ions and water vapor penetration; the long-chain linear aliphatic diamine with a carbon chain length of C6-C12 improves the dispersion uniformity of organic amines in the base oil, ensuring sufficient crosslinking and a dense structure. The synergistic effect of these two components gives the coating both rigidity and flexibility, effectively resisting salt spray corrosion and improving the corrosion resistance and service life of steel-cored aluminum stranded wire in salt spray environments. Detailed Implementation

[0017] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0018] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will be described through embodiments.

[0019] A specific embodiment of the first aspect of the present invention provides a steel-core aluminum stranded wire coated with anti-corrosion grease, comprising a steel core, an aluminum stranded wire layer stranded outside the steel core, and an anti-corrosion coating; the aluminum stranded wire layer is formed by stranding aluminum wires, and the outer periphery of the aluminum stranded wire layer is coated with an anti-corrosion coating; the raw materials of the anti-corrosion coating include the following components in parts by weight: 75-85 parts base oil, 6-10 parts isocyanate, 5-10 parts organic amine, 0.5-1.5 parts fatty alcohol, and 1.5-3 parts anti-corrosion additive; the organic amine includes p-phenylenediamine in a mass ratio of 1:2-3 and straight-chain aliphatic diamines with a carbon chain length of C6-C12, for example, any point value among 1:2, 1:2.2, 1:2.5, 1:3 and any range between any two point values.

[0020] In one embodiment of the present invention, the straight-chain aliphatic diamine with a carbon chain length of C6 to C12 includes 1,6-hexanediamine and 1,12-dodecanediamine in a mass ratio of 1:1 to 2, for example, any point value among 1:1, 1:1.2, 1:1.4, 1:1.5, 1:1.6, 1:1.8, and 1:2, and any range between any two point values.

[0021] In this invention, 1,6 is used. Hexamethylenediamine (a short-chain aliphatic diamine with a carbon chain length of C6~C12) and 1,12 Dodecanediamine (a long-chain aliphatic diamine with a carbon chain length of C6~C12) is compounded in a specific ratio of 1:1~2. Through the synergistic complementarity of long and short chain molecular structures, the polyurea crosslinking network structure is further optimized, improving the salt spray resistance of the coating. Among them, the short-chain 1,6-hexanediamine has short molecular segments, high reactivity, and dense crosslinking sites, which can quickly participate in the isocyanate crosslinking reaction, effectively increasing the overall crosslinking density of the coating, reducing the gaps between crosslinking network molecules, and reducing defects such as micropores and pinholes in the coating at the microscopic level. Meanwhile, the long-chain 1,12-dodecanediamine has… The long hydrophobic carbon chain structure possesses excellent oil-phase compatibility, significantly improving the dispersion uniformity of the organic amine system in the base oil, solving the problems of uneven crosslinking and component agglomeration, and ensuring a uniform and dense overall coating structure without localized weak points in corrosion protection. Furthermore, the long carbon chain exhibits extremely strong hydrophobic barrier properties. When these two components are compounded in a specific ratio, the drawbacks of 1,6-hexanediamine alone—such as brittleness, easy cracking, and poor resistance to humid heat—are avoided, while simultaneously compensating for the deficiencies of 1,12-dodecanediamine alone—such as insufficient crosslinking density, loose structure, and weak mechanical support. Under the specified ratios in this invention, the synergistic effect of long and short chain carbon chain lengths of C6~C12 straight-chain aliphatic diamines, combined with the rigid crosslinking structure of p-phenylenediamine, significantly improves the salt spray corrosion resistance of steel-cored aluminum stranded wire.

[0022] In one embodiment of the present invention, the anti-corrosion additive includes modified silica. The raw materials for the modified silica include silica and a modifier. The modifier includes silane coupling agent KH-550 and silane coupling agent KH-792 in a mass ratio of 5:1 to 2. For example, it can be any point value from 5:1, 5:1.2, 5:1.5, 5:1.8, 5:2 and any range between any two point values.

[0023] In this invention, KH-550 and KH-792 are compounded in a specific ratio of 5:1 to 2 as a modifier to modify the surface of silica, so that an appropriate amount of amino functional groups are grafted onto the surface of silica. This not only completely improves the problem of easy agglomeration and uneven dispersion of nano silica in oil-based anti-corrosion systems, but also achieves a strong bond between inorganic fillers and organic polyurea crosslinking networks through chemical bonding reactions between surface amino groups and isocyanates in the system. This improves the salt spray resistance of the coating in terms of filler dispersibility, interfacial bonding strength, and overall coating density.

[0024] In one embodiment of the present invention, the amount of modifier added is 4% to 6% of the mass of silicon dioxide, for example, it can be any point value among 4%, 4.5%, 5%, 5.5%, 6% and any range between any two point values.

[0025] In one embodiment of the present invention, the average particle size of silicon dioxide is 20~40nm, for example, it can be any point value among 20nm, 25nm, 30nm, 35nm, and 40nm, or any range between any two point values.

[0026] In one embodiment of the present invention, the method for preparing modified silica includes the following steps: dispersing a modifier in water, then adding silica and mixing, followed by drying to obtain modified silica.

[0027] In one embodiment of the present invention, the base oil includes mineral oil.

[0028] In one embodiment of the present invention, the isocyanate includes one or more of toluene diisocyanate, dimethyl diphenylmethane diisocyanate, and diphenylmethane diisocyanate.

[0029] In one embodiment of the present invention, the fatty alcohol includes palmitol.

[0030] A second aspect of the present invention provides a method for preparing a steel-cored aluminum stranded wire coated with anti-corrosion grease, used to prepare the steel-cored aluminum stranded wire coated with anti-corrosion grease provided in the first aspect of the present invention, comprising the following steps: S1. Twist aluminum wires around a steel core to form an aluminum stranded wire layer; S2. After mixing the raw materials for the anti-corrosion coating, apply the mixture to the outer surface of the aluminum stranded wire layer and cure it to form an anti-corrosion coating, thus obtaining anti-corrosion grease coated steel core aluminum stranded wire.

[0031] The present invention will now be described in detail with reference to preferred embodiments and comparative examples. The preferred embodiments of the invention described below can be modified in various ways, and therefore the scope of the invention should not be construed as limited to the preferred embodiments described in detail below. Preferred embodiments are provided to help those skilled in the art to more readily understand the invention.

[0032] Example 1 A method for preparing anti-corrosion grease-coated steel-cored aluminum stranded wire includes the following steps: S1. Twist aluminum wires around a steel core to form an aluminum stranded wire layer; S2. After mixing the raw materials for the anti-corrosion coating, apply the mixture to the outer surface of the aluminum stranded wire layer, control the coating thickness to 80μm, and cure to form an anti-corrosion coating, thus obtaining anti-corrosion grease-coated steel core aluminum stranded wire.

[0033] The raw materials for the anti-corrosion coating include the following components in parts by weight: 75 parts white mineral oil (10#), 6 parts toluene diisocyanate, 5 parts organic amine, 0.5 parts palmitol, and 1.5 parts silica (average particle size 20nm); the organic amine is composed of p-phenylenediamine and straight-chain aliphatic diamine (1,6-hexanediamine) in a mass ratio of 1:2.

[0034] Example 2 A method for preparing anti-corrosion grease-coated steel-cored aluminum stranded wire includes the following steps: S1. Twist aluminum wires around a steel core to form an aluminum stranded wire layer; S2. After mixing the raw materials for the anti-corrosion coating, apply the mixture to the outer surface of the aluminum stranded wire layer, control the coating thickness to 80μm, and cure to form an anti-corrosion coating, thus obtaining anti-corrosion grease-coated steel core aluminum stranded wire.

[0035] The raw materials for the anti-corrosion coating include the following components in parts by weight: 85 parts white mineral oil (10#), 10 parts toluene diisocyanate, 10 parts organic amine, 1.5 parts palmitol, and 3 parts silica (average particle size 40nm); the organic amine is composed of p-phenylenediamine and straight-chain aliphatic diamine (1,6-hexanediamine) in a mass ratio of 1:3.

[0036] Example 3 The only difference from Example 1 is that the organic amine is composed of p-phenylenediamine and a straight-chain aliphatic diamine (1,12-dodecanediamine) in a mass ratio of 1:2.

[0037] Example 4 The only difference from Example 1 is that the organic amine is composed of p-phenylenediamine in a mass ratio of 1:2 and a straight-chain aliphatic diamine (composed of 1,6-hexanediamine and 1,12-dodecanediamine in a mass ratio of 1:1).

[0038] Example 5 The only difference from Example 1 is that the organic amine is composed of p-phenylenediamine and a straight-chain aliphatic diamine (composed of 1,6-hexanediamine and 1,12-dodecanediamine in a mass ratio of 1:2) in a mass ratio of 1:2.

[0039] Example 6 Compared with Example 1, the only difference is that silica is replaced with an equal amount of modified silica. The preparation method of modified silica includes the following steps: dispersing silane coupling agent KH-550 in water, then adding silica (average particle size 20nm), mixing at 40°C for 1.5h, and drying to obtain modified silica; wherein the amount of silane coupling agent KH-550 added is 4% of the mass of silica, and the mass ratio of silica to water is 1:8.

[0040] Example 7 Compared with Example 1, the only difference is that silica is replaced with an equal amount of modified silica. The preparation method of modified silica includes the following steps: dispersing silane coupling agent KH-550 in water, then adding silica (average particle size 20nm), mixing at 40°C for 1.5h, and drying to obtain modified silica; wherein the amount of silane coupling agent KH-550 added is 6% of the mass of silica, and the mass ratio of silica to water is 1:8.

[0041] Example 8 Compared with Example 1, the only difference is that silica is replaced with an equal amount of modified silica. The preparation method of modified silica includes the following steps: dispersing silane coupling agent KH-792 in water, then adding silica (average particle size 20nm), mixing at 40°C for 1.5h, and drying to obtain modified silica; wherein the amount of silane coupling agent KH-792 added is 4% of the mass of silica, and the mass ratio of silica to water is 1:8.

[0042] Example 9 Compared with Example 6, the only difference is that the silane coupling agent KH-550 is replaced with an equal amount of silane coupling agent KH-550-silane coupling agent KH-792 in a mass ratio of 5:1.

[0043] Example 10 Compared with Example 6, the only difference is that the silane coupling agent KH-550 is replaced with an equal amount of silane coupling agent KH-550-silane coupling agent KH-792 in a mass ratio of 5:2.

[0044] Example 11 Compared with Example 6, the only difference is that the silane coupling agent KH-550 is replaced with an equal amount of silane coupling agent KH-550-silane coupling agent KH-792 in a mass ratio of 5:1.5.

[0045] Comparative Example 1 The only difference from Example 1 is that the organic amine is p-phenylenediamine.

[0046] Comparative Example 2 The only difference from Example 1 is that the organic amine is 1,6-hexanediamine.

[0047] Comparative Example 3 The only difference from Example 1 is that the organic amine is 1,12-dodecanediamine.

[0048] In accordance with the test requirements of GB / T 2423.17-2008, the steel-cored aluminum stranded wires of Examples 1-11 and Comparative Examples 1-3 were subjected to a 240-hour salt spray resistance test. The corrosion performance of the aged samples was evaluated by electrochemical potentiodynamic polarization method: the steel-cored aluminum stranded wire samples were immersed in a 3.5wt% NaCl solution, with the sample as the working electrode, a saturated calomel electrode as the reference electrode, and a platinum sheet as the auxiliary electrode. The corrosion current density was determined by potentiodynamic polarization method (scanning rate 0.5mV / s). The test results are shown in Table 1 below.

[0049] Table 1. Salt spray resistance test results of steel-cored aluminum stranded wires in Examples 1-11 and Comparative Examples 1-3

[0050] As shown in Table 1, the salt spray resistance time of Example 1 is greater than that of Comparative Examples 1 to 3. Specifically, compared with Example 1, Comparative Examples 1 to 3 changed the organic amine substances. Therefore, in this invention, the organic amine is limited to p-phenylenediamine and straight-chain aliphatic diamines with carbon chain lengths of C6 to C12, which can improve the salt spray resistance of steel-cored aluminum stranded wire.

[0051] The above are merely 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 within the protection scope of the present invention.

Claims

1. A type of anti-corrosion grease-coated steel-cored aluminum stranded wire, characterized in that, It includes a steel core, an aluminum stranded wire layer stranded around the steel core, and an anti-corrosion coating; the aluminum stranded wire layer is made of stranded aluminum wire, and the outer periphery of the aluminum stranded wire layer is coated with the anti-corrosion coating; the raw materials of the anti-corrosion coating include the following components in parts by weight: 75-85 parts base oil, 6-10 parts isocyanate, 5-10 parts organic amine, 0.5-1.5 parts fatty alcohol, and 1.5-3 parts anti-corrosion additive; the organic amine includes p-phenylenediamine in a mass ratio of 1:2-3 and straight-chain aliphatic diamine with a carbon chain length of C6-C12.

2. The anti-corrosion grease-coated steel-cored aluminum stranded wire according to claim 1, characterized in that, The linear aliphatic diamines with carbon chain lengths of C6 to C12 include 1,6-hexanediamine and 1,12-dodecanediamine in a mass ratio of 1:1 to 2.

3. The anti-corrosion grease-coated steel-cored aluminum stranded wire according to claim 1, characterized in that, The corrosion inhibitor includes modified silica, the raw materials of which include silica and modifier, and the modifier includes silane coupling agent KH-550 and silane coupling agent KH-792 in a mass ratio of 5:1~2.

4. The anti-corrosion grease-coated steel-cored aluminum stranded wire according to claim 3, characterized in that, The amount of the modifier added is 4% to 6% of the mass of silica.

5. The anti-corrosion grease-coated steel-cored aluminum stranded wire according to claim 3, characterized in that, The average particle size of the silica is 20~40nm.

6. The anti-corrosion grease-coated steel-cored aluminum stranded wire according to claim 3, characterized in that, The method for preparing the modified silica includes the following steps: dispersing the modifier in water, then adding silica and mixing, followed by drying to obtain the modified silica.

7. The anti-corrosion grease-coated steel-cored aluminum stranded wire according to claim 1, characterized in that, The base oil includes mineral oil.

8. The anti-corrosion grease-coated steel-cored aluminum stranded wire according to claim 1, characterized in that, The isocyanate includes one or more of toluene diisocyanate, dimethyl diphenylmethane diisocyanate, and diphenylmethane diisocyanate.

9. The anti-corrosion grease-coated steel-cored aluminum stranded wire according to claim 1, characterized in that, The fatty alcohols include palmitol.

10. A method for preparing anti-corrosion grease-coated steel-cored aluminum stranded wire, used to prepare the anti-corrosion grease-coated steel-cored aluminum stranded wire according to any one of claims 1 to 9, characterized in that, Includes the following steps: S1. Twist aluminum wires around a steel core to form an aluminum stranded wire layer; S2. After mixing the raw materials of the anti-corrosion coating, apply it to the outer surface of the aluminum stranded wire layer and cure it to form an anti-corrosion coating, thus obtaining anti-corrosion grease coated steel core aluminum stranded wire.

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