Conductor repair method

Abstract

The application provides a conductor repairing method. The method comprises the following steps: filling a conductor repairing material to a to-be-repaired part of a conductor, and then performing first solidification to form a repairing interface at the to-be-repaired part of the conductor; covering an insulating repairing material on the surface of the repairing interface, and then performing second solidification to form an insulating isolation film on the surface of the repairing interface; wherein the conductor repairing material comprises a polymer base material, an additive, metal powder and metal fibers; and the insulating repairing material comprises a polymer base material and an additive. By adding the metal powder and the metal fibers, the corrosion potential difference can be greatly reduced while the good conductivity is maintained; the self-solidified insulating waterproof isolation film is formed by using the insulating repairing material, and the self-solidified insulating waterproof isolation film has good corrosion resistance and high mechanical strength; the repairing process can be performed under low temperature conditions; the repaired conductor has good conductivity, corrosion resistance, waterproofness and mechanical properties; and the repaired conductor is suitable for repairing cable terminals.

Description

Technical Field

[0001] The present invention relates to the technical field of metal conductor repair, and in particular to a conductor repair method. Background Art

[0002] High-voltage cables and terminals are expensive to manufacture, but conductor corrosion, cracks, and other defects or failures are common. These defects necessitate replacement of the entire connector or cable, resulting in significant financial losses. Currently, no reliable technology for repairing metal conductors at low temperatures with corrosion resistance has been reported. Conventional repair methods can exacerbate corrosion due to the potential difference between the conductor and the repair material in the repaired area.

[0003] To prevent other materials and structures inside the cable from being damaged by high temperatures, high-temperature repair methods such as welding and melt casting cannot be used. Conventional repair materials are conductive carbon-based materials, which suffer from contact corrosion and crevice corrosion in the gaps between them and metal conductors. This is a deterioration phenomenon caused by the difference in corrosion potential between metal materials and dissimilar materials. In cable systems, current inevitably flows through the conductors, which causes their current density to be much higher than that of ordinary metal components, thereby increasing the migration rate of electrons and ions, causing corrosion to intensify, resulting in serious consequences such as hydrogen evolution and conductor damage. Repair materials need to meet high electrical conductivity while also having certain mechanical properties, bonding properties, etc.

[0004] At present, when using conductor repair materials on the market such as aluminum fillers (the matrix is ​​mainly epoxy resin) for repair, the following problems will arise: these materials have poor conductivity, low adhesion to conductors, inconvenient use, and a large difference in corrosion potential between them and the conductors (most of the conductive additives inside are carbon-based materials such as carbon black powder, graphene, and untreated carbon nanotubes). After repair, it is easy to cause contact corrosion and crevice corrosion of the conductor, and cannot effectively repair conductor damage in fields such as high-voltage cable transmission lines. Summary of the Invention

[0005] The main purpose of the present invention is to provide a conductor repair method to solve the problems in the prior art that conductor repair methods require high temperature repair, are difficult to implement, and are prone to conductor corrosion, reduced conductivity, and reduced reliability after repair.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a conductor repair method is provided, comprising the following steps: step S1, filling a conductor repair material into a portion of the conductor to be repaired, and then performing a first curing to form a repair interface at the portion of the conductor to be repaired; step S2, covering the surface of the repair interface with an insulating repair material, and then performing a second curing to form an insulating isolation film on the surface of the repair interface; wherein the conductor repair material comprises a polymer matrix, an additive, metal powder and metal fiber; and the insulating repair material comprises a polymer matrix and an additive.

[0007] Furthermore, the conductor repair material includes, by weight, 100 parts of a polymer matrix, 1 to 2 parts of an additive, 20 to 50 parts of metal powder, and 20 to 38 parts of metal fiber; the insulation repair material includes 100 parts of a polymer matrix and 1 to 2 parts of an additive.

[0008] Furthermore, the polymer matrix includes condensation silicone rubber and / or EVA; preferably, the condensation silicone rubber includes one or more of dealcoholized silicone rubber, deoximated silicone rubber and deacetone silicone rubber; and / or the VA content in the EVA is 18-40%.

[0009] Furthermore, the additive includes maleic anhydride and / or zeolite powder; preferably, the size of the zeolite powder is 100-8000 mesh.

[0010] Furthermore, the size of the metal powder is 100 to 8000 mesh; preferably, the metal powder includes one or more of aluminum powder, copper powder, lead powder, nickel powder, silver powder, gold powder and platinum powder; more preferably, the metal powder includes aluminum powder and / or copper powder.

[0011] Furthermore, the diameter of the metal fiber is 10 to 30 μm, and the aspect ratio is 10 to 30; preferably, the metal fiber includes one or more of aluminum fiber, copper fiber, lead fiber, nickel fiber, silver fiber, gold fiber and platinum fiber; more preferably, the metal fiber includes aluminum fiber and / or copper fiber.

[0012] Furthermore, the first curing temperature is 0-50° C., and the time is 0.25-24 hours.

[0013] Furthermore, the second curing temperature is 0 to 50° C., and the time is 0.25 to 24 hours, preferably 10 to 15 hours.

[0014] Furthermore, the thickness of the insulating isolation film is 0.01 to 50 mm.

[0015] Furthermore, step S1 further includes the following steps: physically polishing and chemically cleaning the portion of the conductor to be repaired in sequence, and then filling the portion of the conductor to be repaired with a conductor repair material; preferably, chemical cleaning is performed using one or more of alcohol, water and toluene.

[0016] The present invention utilizes a polymer matrix with excellent adhesion to metal conductors for repair, and incorporates metal powder and metal fiber materials with corrosion potentials close to that of the conductor material. This significantly reduces the corrosion potential difference while maintaining good conductivity. After the conductor repair material has substantially repaired the conductor defect, an insulating repair material with the same base material as the conductor repair material is used to cover the resulting repair interface, forming a self-curing insulating and waterproof barrier membrane. This membrane exhibits excellent adhesion, eliminating the need for adhesives, and possesses excellent corrosion resistance and high mechanical strength.

[0017] The present invention provides a conductor repair method that is less susceptible to conductor corrosion and maintains high conductivity and reliability after repair. The repair process can be performed under low-temperature conditions or under power, maintaining the original properties of the metal conductor. The repaired conductor has good conductivity, water resistance, and mechanical properties, meeting the requirements for use in various harsh environments. The low-temperature repair method for metal conductors of the present invention has the advantages of simple operation, significant results, and a wide range of applications. It is suitable for repairing cable terminals, providing a new solution for maintaining and extending the service life of cable systems, and has broad application prospects in the field of repairing high-voltage system conductors. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 A schematic diagram of a repair process according to an embodiment of the present invention is shown;

[0020] Figure 2 The SEM morphology of the repaired surface of the repaired cable conductor after immersion in water according to Comparative Example 1 is shown;

[0021] Figure 3 The SEM morphology of the repaired surface of the repaired cable conductor after being soaked in water according to Example 1 of the present invention is shown. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0023] As described in the background of the present invention, the existing conductor repair methods have the problem that they require high temperature repair, are difficult to implement, and are prone to conductor corrosion, reduced conductivity, and reduced reliability after repair. In order to solve the above problems, in a typical embodiment of the present invention, a conductor repair method is provided, comprising the following steps: step S1, filling the conductor repair material into the part to be repaired of the conductor, and then performing a first curing to form a repair interface at the part to be repaired of the conductor; step S2, covering the surface of the repair interface with an insulating repair material, and then performing a second curing to form an insulating isolation film on the surface of the repair interface; wherein the conductor repair material includes a polymer matrix, an additive, a metal powder, and a metal fiber; and the insulating repair material includes a polymer matrix and an additive.

[0024] Specifically, the conductor repair material is first filled into the defects, cracks, and gaps of the conductor waiting to be repaired in the repair shape template (optional), and then the first curing is carried out. After the initial solidification, a repair interface is formed at the part of the conductor to be repaired; then the insulating repair material is covered on the surface of the repair interface, and the interface between the conductor repair material and the conductor is covered, and then a second curing is carried out to make the conductor repair material and the insulating repair material completely cured to form a self-curing insulating and waterproof isolation film on the surface of the repair interface, isolating the electrolyte and preventing the presence of electrolyte at the contact point of the two conductive materials, so as to eliminate contact corrosion and fill the gap between the two conductive materials, thereby eliminating crevice corrosion, so that the repaired conductor has good conductivity, corrosion resistance and mechanical properties.

[0025] The conductor repair material of the present invention uses metal powder and metal fibers as conductive fillers, with metal fibers having a similar corrosion potential to the conventional conductor being repaired. Metal fibers with similar corrosion potentials are used to construct a conductive network, and the addition of metal powders with similar corrosion potentials synergistically enhances conductivity. Using materials with similar corrosion potentials to the conductor for repair also helps reduce potential electrochemical reactions after repair, improving the stability of the repair effect.

[0026] The insulating repair material of the present invention is primarily used to isolate the interface between the conductor after initial repair and the conductor repair material. Because its resistivity is much higher than that of the conductor, current cannot flow through this layer. It also effectively isolates electrolytes and prevents contact corrosion. Furthermore, the insulating repair material shares the same non-metallic components as the conductor repair material and exhibits self-curing properties, eliminating the need for additional adhesives that can corrode metal surfaces. This improves moisture resistance at the repaired site, enhances corrosion resistance while maintaining adhesion, and extends the life of the conductor.

[0027] A schematic diagram of the repair process of an embodiment of the present invention is shown in FIG. Figure 1As shown, a small potential difference between the conductor repair material and the metal being repaired is a significant advantage because it can reduce or prevent the occurrence of electrochemical corrosion. If the potential difference between the two materials is small, the metal is less likely to be affected by electrochemical corrosion. This is because a smaller potential difference means less current is generated during electrochemical corrosion, reducing the dissolution and corrosion of the metal.

[0028] In addition, using an insulating separator with the same matrix as the conductor repair material (which can increase adhesion to the conductor repair material) to cover the interface between the conductor repair material and the metal material also helps prevent electrolytes from entering the contact interface, further reducing the risk of electrochemical corrosion. The insulating separator can prevent the penetration of electrolytes, thereby reducing the possibility of current passing through. Due to the high resistance, when contacting the metal surface, the current will bypass the insulating separator and flow from other locations. Therefore, the insulating separator protects the interface between the fragile conductor repair material and the material to be repaired, preventing the intrusion of moisture or other electrolytes, and reducing the risk of electrochemical corrosion.

[0029] In summary, the small potential difference between the conductor repair material and the metal material to be repaired, the isolation by the insulating isolation film, and the large resistance all help reduce the risk of electrochemical corrosion and protect the metal material from corrosion.

[0030] The present invention provides a conductor repair method that is less susceptible to conductor corrosion and maintains high conductivity and reliability after repair. The repair process can be performed under low-temperature conditions or under power, maintaining the original properties of the metal conductor. The repaired conductor has good conductivity, water resistance, and mechanical properties, meeting the requirements for use in various harsh environments. The low-temperature repair method for metal conductors of the present invention has the advantages of simple operation, significant results, and a wide range of applications. It is suitable for repairing cable terminals, providing a new solution for maintaining and extending the service life of cable systems, and has broad application prospects in the field of repairing high-voltage system conductors.

[0031] In a preferred embodiment, the conductor repair material comprises, by weight, 100 parts polymer matrix, 1-2 parts additive, 20-50 parts metal powder, and 20-38 parts metal fiber; the insulation repair material comprises 100 parts polymer matrix and 1-2 parts additive. This composition of the conductor repair material enhances conductivity by synergistically building a conductive network between the metal fiber and the metal powder, and also enhances corrosion resistance through the synergistic combination of the polymer matrix and the additive, further enhancing the reliability of the repair method.

[0032] In order to further improve the adhesion performance between the material used for conductor repair and the metal conductor and extend the service life of the conductor after repair, in a preferred embodiment, the polymer substrate includes condensation silicone rubber and / or EVA; preferably, the condensation silicone rubber includes one or more of dealcoholized silicone rubber, deoximated silicone rubber and deacetone silicone rubber; and / or the VA content in the EVA is 18-40%.

[0033] In a preferred embodiment, the additive includes maleic anhydride and / or zeolite powder; preferably, the zeolite powder has a size of 100 to 8000 mesh. These additives can better absorb small molecules released by the polymer substrate during curing, further preventing metal corrosion while ensuring a smooth surface.

[0034] During the specific implementation process, the conductive network construction filler with a similar corrosion potential to the conductor to be repaired can be flexibly determined according to the repair scenario. In a preferred embodiment, the size of the metal powder is 100 to 8000 mesh; preferably, the metal powder includes one or more of aluminum powder, copper powder, lead powder, nickel powder, silver powder, gold powder and platinum powder; more preferably, the metal powder includes aluminum powder and / or copper powder. The above-mentioned ultrafine spherical metal powder is conducive to utilizing its metallic properties to further enhance the conductivity of the conductive material, thereby further increasing the conductivity of the repaired conductor.

[0035] For similar reasons, during implementation, fiber fillers with similar corrosion potentials to the conductor being repaired can be flexibly selected based on the metal substrate being repaired to construct a conductive network. In a preferred embodiment, the metal fibers have a diameter of 10 to 30 μm and an aspect ratio of 10 to 30. Preferably, the metal fibers include one or more of aluminum fibers, copper fibers, lead fibers, nickel fibers, silver fibers, gold fibers, and platinum fibers. More preferably, the metal fibers include aluminum fibers and / or copper fibers.

[0036] In a preferred embodiment, the first curing temperature is 0-50° C. and the time is 0.25-24 hours, so that the conductor repair material can be initially cured to a more suitable degree, forming a repair interface that is more convenient for subsequent insulation repair material to cover.

[0037] In order to allow the conductor repair material and the insulation repair material to be more fully cured during the repair process, in a preferred embodiment, the second curing temperature is 0-50° C. and the time is 0.25-24 hours, preferably 10-15 hours.

[0038] In a preferred embodiment, the thickness of the insulating isolation film is 0.01 to 50 mm. The insulating isolation film of the above thickness can further improve the corrosion resistance and reliability of the repaired conductor.

[0039] In order to ensure that the portion of the conductor to be repaired is smooth and flat before repair, with no residual corrosion products, thereby facilitating the adhesion and retention of the repair material, in a preferred embodiment, step S1 further comprises the following steps: physically grinding and chemically cleaning the portion of the conductor to be repaired, followed by filling the portion of the conductor to be repaired with the conductor repair material; preferably, chemical cleaning is performed using one or more of alcohol, water, and toluene. Preferably, the conductor fracture (portion to be repaired) is cleaned using one or more of a knife, a cutter, a grinder, scissors, and pliers to remove corrosion products (if any) on the cross section, and the fracture is polished using one or more of a grinder and sandpaper.

[0040] Typically, but not limited to, the conductor repair material comprises 100 parts of a polymer matrix, 1 part, 1.5 parts, 2 parts, or a range consisting of any two of the additives, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, or a range consisting of any two of the metal powders, and 20 parts, 25 parts, 30 parts, 35 parts, 38 parts, or a range consisting of any two of the metal fibers; the insulation repair material comprises 100 parts of a polymer matrix, 1 part, 1.5 parts, 2 parts, or a range consisting of any two of the additives.

[0041] Typically, but not limited to, the size of the metal powder is 100 mesh, 1000 mesh, 2000 mesh, 3000 mesh, 4000 mesh, 5000 mesh, 6000 mesh, 7000 mesh, 8000 mesh, or a range consisting of any two of them; the diameter of the metal fiber is 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, or a range consisting of any two of them; and the aspect ratio is 10, 15, 20, 25, 30, or a range consisting of any two of them.

[0042] Typically, but not limitatively, the temperature of the first curing is 0°C, 10°C, 20°C, 30°C, 0°C, 50°C or a range consisting of any two of them, and the time is 0.25h, 1h, 2h, 5h, 10h, 15h, 20h, 24h or a range consisting of any two of them; the temperature of the second curing is 0°C, 10°C, 20°C, 30°C, 0°C, 50°C or a range consisting of any two of them, and the time is 0.25h, 1h, 2h, 5h, 10h, 15h, 20h, 24h or a range consisting of any two of them.

[0043] Typically, but not limiting, the thickness of the insulating isolation film is 0.01 mm, 1 mm, 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, or a range consisting of any two of these values.

[0044] The present application is further described in detail below with reference to specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in this application.

[0045] Unless otherwise specified, the conductor to be repaired in the Examples and Comparative Examples is a cable, and the materials used can be readily purchased from the market or prepared using conventional methods in the art. Exemplary sources are as follows:

[0046] Ultrafine spherical aluminum powder: Henan Yuanyang Powder Technology Co., Ltd., FLPG 7.5;

[0047] Short diameter aluminum micron fiber: homemade, aluminum wire was drawn using a wet continuous wire drawing machine at a drawing speed of about 1.0 m / min, with a vacuum degree of 10×10 -5 Pa, stretched from an outer diameter of 1.0 mm to 20 μm, and subsequently chopped using a fiber cutter with an aspect ratio of 20.

[0048] Example 1

[0049] The conductor repair material includes 100 parts of a polymer matrix (dealcoholized silicone rubber), 1.5 parts of an additive (maleic anhydride), 20 parts of ultrafine spherical aluminum powder, and 35 parts of metal fiber (short-diameter aluminum micron fiber). The conductor repair material is obtained by mixing the above materials for 1 hour.

[0050] The insulation repair material includes 100 parts of a polymer base material (dealcoholized silicone rubber) and 1.5 parts of an additive (maleic anhydride). The above materials are mixed for 1 hour to obtain the insulation repair material.

[0051] Step S1: cleaning and polishing the conductor fracture, cleaning the metal surface with anhydrous alcohol to make it smooth and flat; filling the conductor repair material into the conductor to be repaired part, and then performing a first curing at a temperature of 30° C. for 12 hours to form a repair interface at the conductor to be repaired part;

[0052] Step S2, covering the surface of the repair interface with an insulating repair material, and then performing a second curing at a temperature of 30° C. for 12 hours to form an insulating isolation film on the surface of the repair interface with a thickness of 30 mm.

[0053] Example 2

[0054] The conductor repair material includes 100 parts of a polymer matrix (EVA, VA content of 30%), 1.5 parts of an additive (maleic anhydride), 20 parts of ultrafine spherical aluminum powder, and 35 parts of metal fiber (short-diameter aluminum micron fiber). The conductor repair material is obtained by mixing the above materials for 1 hour.

[0055] The insulation repair material includes 100 parts of a polymer base material (dealcoholized silicone rubber) and 1.5 parts of an additive (maleic anhydride). The above materials are mixed for 1 hour to obtain the insulation repair material.

[0056] Step S1: cleaning and polishing the conductor fracture, cleaning the metal surface with anhydrous alcohol to make it smooth and flat; filling the conductor repair material into the conductor to be repaired part, and then performing a first curing at a temperature of 30° C. for 12 hours to form a repair interface at the conductor to be repaired part;

[0057] Step S2, covering the surface of the repair interface with an insulating repair material, and then performing a second curing at a temperature of 30° C. for 12 hours to form an insulating isolation film on the surface of the repair interface with a thickness of 30 mm.

[0058] Example 3

[0059] The difference from Example 1 is:

[0060] The conductor repair material includes 100 parts of a polymer matrix (EVA, VA content of 18%), 1 part of an additive (zeolite powder 100 mesh), 20 parts of a metal powder (aluminum powder, 100 mesh), and 38 parts of a metal fiber (aluminum fiber, diameter of 10 μm, aspect ratio of 10);

[0061] The insulation repair material includes 100 parts of a polymer base material (EVA, VA content of 18%) and 1 part of an additive (zeolite powder 100 meshes).

[0062] Example 4

[0063] The difference from Example 1 is:

[0064] The conductor repair material includes 100 parts of a polymer matrix (EVA, VA content of 40%), 2 parts of an additive (zeolite powder 8000 mesh), 50 parts of a metal powder (copper powder, 8000 mesh), and 20 parts of a metal fiber (copper fiber, diameter of 30 μm, aspect ratio of 30);

[0065] The insulation repair material includes 100 parts of a polymer base material (EVA, VA content of 40%) and 2 parts of an additive (zeolite powder 8000 mesh).

[0066] Example 5

[0067] The difference from Example 1 is:

[0068] Step S1: cleaning and polishing the conductor fracture, cleaning the metal surface with anhydrous alcohol to make it smooth and flat; filling the conductor repair material into the conductor to be repaired part, and then performing a first curing at a temperature of 0°C for 24 hours to form a repair interface at the conductor to be repaired part;

[0069] Step S2, covering the surface of the repair interface with an insulating repair material, and then performing a second curing at a temperature of 0° C. for 24 hours to form an insulating isolation film on the surface of the repair interface with a thickness of 50 mm.

[0070] Example 6

[0071] The difference from Example 1 is:

[0072] Step S1: cleaning and polishing the conductor fracture, cleaning the metal surface with anhydrous alcohol to make it smooth and flat; filling the conductor repair material into the conductor to be repaired part, and then performing a first curing at a temperature of 50° C. for a time of 0.25 h to form a repair interface at the conductor to be repaired part;

[0073] Step S2, covering the surface of the repair interface with an insulating repair material, and then performing a second curing at a temperature of 50° C. for 0.25 h to form an insulating isolation film on the surface of the repair interface with a thickness of 0.01 mm.

[0074] Comparative Example 1

[0075] The difference from Example 1 is that an aluminum repair agent (Hui Rui HR-8113 aluminum repair agent) is used to repair the conductor.

[0076] Comparative Example 2

[0077] The difference from Example 1 is that step S2 is not performed.

[0078] Performance testing:

[0079] The conductor repair materials and the repaired conductors of the above examples and comparative examples were subjected to performance tests. The results are shown in Tables 1 and 2.

[0080] Peel strength test: Peel strength was tested according to GB / T 2791-1995. The prepared conductor repair material was placed in a flat-plate vulcanizer at 120°C to form a 1cm×10cm×0.2cm specimen. The specimen was then press-formed with a 1cm×10cm×0.1cm aluminum sheet in the same flat-plate vulcanizer (EVA-based materials were hot-pressed at 120°C and 15 MPa for 15 minutes, while silicone rubber-based materials were hot-pressed at room temperature and 15 MPa for 15 minutes). This yielded a hot-pressed conductor repair material / aluminum sheet composite strip. The strip was then stretched using a tensile testing machine, and the resulting tensile force was used as the peel strength.

[0081] Conductivity test:The conductor repair material was pressed into a 10mm×10mm×3mm sheet. The polarization-depolarization curve was tested using three electrodes (the bottom electrode was connected to low voltage, the middle electrode was connected to high voltage, and the outer electrode at the high voltage end was grounded), and the conductive properties of the conductor were obtained by fitting.

[0082] Corrosion potential test: The conductor repair material was made into a 1cm×1cm×0.2mm thin sheet as an auxiliary electrode, clamped with a platinum electrode clamp and immersed in an electrolytic cell filled with 3.5% sodium chloride together with a 1cm×1cm×0.2mm aluminum working electrode and a saturated calomel reference electrode. The open circuit potential was tested using a Chenhua electrochemical workstation CHI760, and the time was set to 400s.

[0083] Neutral salt spray corrosion test: After the repaired conductor material has cured for 24 hours, its corrosion performance in a salt spray environment is evaluated according to standard GB / T12967.3-2022. The test samples are exposed to a salt spray environment containing sodium chloride (concentration of 50g / L) for 48 hours. The salt water solution is sprayed on the sample surface. The degree of corrosion of the samples is monitored and evaluated by visually observing the corrosion marks on the sample surface and calculating the corrosion area.

[0084] Current water corrosion test: After the repaired conductor material has cured for 24 hours, the repaired area is immersed in water and a 0.01 mA current is applied for 48 hours to observe the extent of corrosion at the connection. After the test is complete, SEM morphology is characterized (the insulating film covering the interface is removed during SEM testing to characterize the interface).

[0085] Table 1

[0086]

[0087] As can be seen from Table 1, compared with Comparative Example 1, the conductor repair material of Comparative Example 2 has higher peel strength, lower resistivity, and very low potential difference in corrosion potential, showing more superior performance; compared with Comparative Example 2, the conductor repair materials of each embodiment have good insulation properties.

[0088] Table 2

[0089]

[0090] As can be seen from the above, the appearance of Comparative Examples 1 and 2 showed corrosion on the surface, and the protection level was failed (level 8), with severe discoloration. In contrast, the samples of the examples showed no signs of corrosion on the surface, and the protection level was passed (level 9.5), with little or no discoloration. The results of the current immersion corrosion test show that the sample of Comparative Example 1 showed severe corrosion at the connection, while the sample of Example 1 showed almost no corrosion at the connection.

[0091] The SEM morphology of the repaired surface of the repaired cable conductor of Comparative Example 1 after soaking in water is shown in Figure 2 ; The SEM morphology of the repaired cable conductor of Example 1 after soaking in water is shown in the repaired surface Figure 3 As can be seen from the SEM image, in the current-immersion corrosion test, the degree of corrosion at the interface between the conductor to be repaired and the conductor repair material in Example 1 is relatively small, showing better corrosion resistance and insulation performance, and is suitable for repair work.

[0092] As can be seen from the above, compared with the comparative examples, the embodiments of the present invention use a polymer matrix with good adhesion to the metal conductor for repair, and add metal powder and metal fiber materials with a corrosion potential close to that of the conductor material, which can significantly reduce the corrosion potential difference while maintaining good conductivity. After the conductor repair material has basically repaired the conductor defect, an insulating repair material with the same base material as the conductor repair material is used to cover the surface of the repaired area to form a self-curing insulating and waterproof isolation membrane. It has good adhesion and therefore does not require the addition of adhesives. It also has good corrosion resistance and high mechanical strength. The method of the present invention of first using a conductor repair material to repair the conductor and then covering the repair interface with an insulating repair material can overcome the problem of easy corrosion of the conductor after repair.

[0093] In addition, it can be seen that when all process parameters are within the preferred range of the present invention, the overall effect is better.

[0094] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A conductor repair method, characterized in that: The following steps are involved: Step S1, filling the conductor repair material into the portion to be repaired of the conductor, and then performing a first curing to form a repair interface at the portion to be repaired of the conductor; Step S2, covering the surface of the repair interface with an insulating repair material, and then performing a second curing to form an insulating isolation film on the surface of the repair interface; Wherein, the conductor repair material includes a polymer matrix, an additive, metal powder and metal fiber; the insulation repair material includes the polymer matrix and the additive.

2. The conductor repair method according to claim 1, characterized in that: By weight, The conductor repair material comprises 100 parts of the polymer matrix, 1 to 2 parts of the additive, 20 to 50 parts of the metal powder, and 20 to 38 parts of the metal fiber; The insulation repair material includes 100 parts of the polymer base material and 1 to 2 parts of the additive.

3. The conductor repair method according to claim 1 or 2, characterized in that: The polymer matrix includes condensation-type silicone rubber and / or EVA.

4. The conductor repair method according to claim 3, characterized in that: The condensation-type silicone rubber includes one or more of dealcohol-type silicone rubber, deoxime-type silicone rubber and deacetone-type silicone rubber; and / or the VA content in the EVA is 18-40%.

5. The conductor repair method according to claim 1 or 2, characterized in that: The additives include maleic anhydride and / or zeolite powder.

6. The conductor repair method according to claim 5, characterized in that: The size of the zeolite powder is 100-8000 mesh.

7. The conductor repair method according to claim 1 or 2, characterized in that: The size of the metal powder is 100-8000 mesh.

8. The conductor repair method according to claim 1 or 2, characterized in that: The metal powder includes one or more of aluminum powder, copper powder, lead powder, nickel powder, silver powder, gold powder and platinum powder.

9. The conductor repair method according to claim 1 or 2, characterized in that: The metal powder includes aluminum powder and / or copper powder.

10. The conductor repair method according to claim 1 or 2, characterized in that: The metal fiber has a diameter of 10-30 μm and an aspect ratio of 10-30.

11. The conductor repair method according to claim 1 or 2, characterized in that: The metal fibers include one or more of aluminum fibers, copper fibers, lead fibers, nickel fibers, silver fibers, gold fibers, and platinum fibers.

12. The conductor repair method according to claim 1 or 2, characterized in that: The metal fibers include aluminum fibers and / or copper fibers.

13. The conductor repair method according to claim 1 or 2, characterized in that: The temperature of the first curing is 0-50° C., and the time is 0.25-24 hours.

14. The conductor repair method according to claim 1 or 2, characterized in that: The second curing temperature is 0-50° C., and the curing time is 0.25-24 hours.

15. The conductor repair method according to claim 14, characterized in that: The second curing time is 10 to 15 hours.

16. The conductor repairing method according to claim 1 or 2, characterized in that: The thickness of the insulating isolation film is 0.01-50 mm.

17. The conductor repairing method according to claim 1 or 2, characterized in that: The step S1 further includes the following steps: physically polishing and chemically cleaning the portion of the conductor to be repaired in sequence, and then filling the portion of the conductor to be repaired with the conductor repair material.

18. The conductor repairing method according to claim 17, characterized in that: The chemical cleaning is performed using one or more of alcohol, water, and toluene.

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