A hollow sandwich steel pipe concrete electric pole anticorrosion method

Abstract

The present application relates to the field of corrosion protection technology, in particular to a hollow sandwich steel pipe concrete pole corrosion protection method. According to the characteristics of different positions, the corresponding corrosion protection process is set, the inner steel pipe is sealed and physically isolated at both ends, the pole body surface is brushed with corrosion protection paint, and the flange node is brushed with corrosion protection paint and then covered with mineral paste. The anticorrosion oil paste is obtained by adding 10% calcium petroleum sulfonate and 2% oxidized petroleum grease barium soap in the base mineral anticorrosion paste. The hollow sandwich steel pipe concrete pole achieves the best corrosion protection effect, avoids the problems of environmental pollution and poor corrosion protection effect in heavy corrosion environment caused by traditional hot-dip galvanizing, and reduces the pole corrosion protection cost.

Description

Technical Field

[0001] This invention relates to the field of corrosion protection technology, specifically to a method for corrosion protection of hollow sandwich steel pipe concrete poles. Background Technology

[0002] Hollow-core steel-concrete composite poles are a new type of composite pole. Their structure consists of two concentric steel tubes of different diameters, with concrete poured between them to form a columnar structure. Under stress, the steel tubes restrain the concrete, improving its plasticity and toughness. The presence of concrete delays local buckling of the steel tubes. This prevents sudden failure of the steel pole under extreme external forces and enhances its resistance to extreme disasters. These composite poles feature high load-bearing capacity, high safety, convenient construction, and good economic efficiency, making them promising for applications in transmission lines and substations / converter stations.

[0003] The corrosion of steel components in the natural environment is a spontaneous and irreversible process. Taking effective anti-corrosion measures to delay the corrosion of composite power poles is crucial to ensuring their long-term effectiveness. Applying an anti-corrosion coating to the surface of the steel pipe is usually an effective method, as the coating acts as a barrier, preventing moisture, oxygen, and ions from entering the metal interface and causing oxidation-reduction reactions that corrode the steel pipe. Hot-dip galvanizing is currently the most widely used anti-corrosion technology for power transmission lines both domestically and internationally. Its main advantages are controllable zinc coating thickness, toughness, and surface condition, resulting in high corrosion resistance. However, hot-dip galvanizing has poor corrosion resistance in industrial atmospheric environments and coastal marine salt spray environments, leading to a short service life. Furthermore, both pickling and hot-dip galvanizing processes cause serious environmental pollution, subject to national environmental protection policies.

[0004] Chinese patent CN 113600462A describes a composite steel pipe with a composite coating formed by electrostatic powder spraying (CSP) in one step, followed by a second CSP to form a composite coating (CSP) in another step, and finally polyethylene coating. Both CSP and CSP include epoxy resin and nano-ceramic powder, with CSP also including an adhesive. Chinese patent CN 114933835A describes a two-layer anti-corrosion coating. The first layer is a chelate layer formed on the steel pipe surface by metallic iron and disodium ethylenediaminetetraacetate. This chelate layer improves both the corrosion resistance and surface roughness of the steel pipe, thus enhancing the adhesion of the anti-corrosion coating. The second layer is an anti-corrosion coating layer. The water-soluble acrylic resin in this layer is modified with 1-(3,4-dihydroxyphenyl)-2-aminoethanol, so that the carboxyl groups of the acrylic resin and the amino groups of 1-(3,4-dihydroxyphenyl)-2-aminoethanol react to achieve the purpose of grafting acrylic resin with 1-(3,4-dihydroxyphenyl)-2-aminoethanol. 1-(3,4-dihydroxyphenyl)-2-aminoethanol contains 3 hydroxyl groups, especially the two ortho-phenolic hydroxyl groups, which have excellent adhesion to the steel pipe surface, which can greatly improve the adhesion ability of the anti-corrosion coating to the steel pipe and make it less likely to fall off.

[0005] The aforementioned existing technologies primarily focus on improving anti-corrosion coatings and treatment processes, but do not provide specific solutions for corrosion protection of steel pipes with special structures or at pipe joints. Therefore, how to develop corresponding anti-corrosion processes based on the structure of special steel pipes is an urgent problem to be solved at this stage. Summary of the Invention

[0006] To address the current problems in corrosion protection of hollow steel tube concrete poles, this invention provides a method for corrosion protection of hollow steel tube concrete poles. Based on the characteristics of hollow steel tubes, appropriate anti-corrosion coatings and processes are implemented. This involves sealing both ends of the inner steel tube for physical isolation, applying anti-corrosion coating to the outer surface of the pole, and locally covering the flange joints with petrolatum paste. This achieves optimal corrosion protection for the composite pole, avoiding the environmental pollution and poor corrosion resistance in heavily corrosive environments associated with traditional hot-dip galvanizing, while also reducing the cost of pole corrosion protection.

[0007] The technical solution of the present invention is as follows: A method for corrosion protection of hollow steel-concrete composite utility poles includes pole body corrosion protection and joint corrosion protection; the pole body corrosion protection includes external steel pipe corrosion protection and internal steel pipe corrosion protection. The outer steel pipe is protected by brushing on anti-corrosion coating; the inner steel pipe is protected by sealing both ends of the inner steel pipe to physically isolate it from external corrosive agents. The node corrosion protection includes: applying anti-corrosion coating in atmospheric corrosion environments of C1-C4 level; and applying anti-corrosion coating in atmospheric corrosion environments of C5 and above level, followed by localized petrolatum coating for corrosion protection.

[0008] Furthermore, the corrosion prevention method includes the following steps: (1) Surface treatment: The surface treatment of steel components shall reach St2 or the original rust state; (2) Apply anti-corrosion coating to the outer steel pipe: Apply the coating from top to bottom and from inside to outside; (3) Physical isolation corrosion protection of inner steel pipe: use thin steel plate to seal the through holes on the upper and lower flanges of inner steel pipe with metal repair glue. After sealing, the height of the thin steel plate shall not be higher than the height of the flange. (4) Node corrosion protection: Apply anti-corrosion coating in atmospheric corrosion environment of C1-C4 level, and apply anti-corrosion coating in atmospheric corrosion environment of C5 and above level, followed by local petrolatum coating for corrosion protection.

[0009] Preferably, the primer used comprises two components, A and B. Component A mainly includes: 30-50 parts epoxy resin, 190-280 parts zinc powder, 2-4 parts rust conversion agent, 1-2 parts defoamer, 1-2 parts dispersant, 0.5-1 parts leveling agent, 20-30 parts solvent, and 4-6 parts silane coupling agent. Component B is 30-50 parts curing agent.

[0010] Preferably, the corrosion conversion agent is one or more of zinc chromate, zinc phosphate, and aluminum tripolyphosphate; And / or the defoamer is: BYK1681 and / or BYK054; And / or the dispersant is: BYK110 and / or BYK1165; And / or the leveling agent is: BYK-GO 8730 and / or BYK410; And / or the solvent is: xylene and / or n-butanol; And / or the curing agent is: ZY-2015C.

[0011] Preferably, the dry film thickness of the coating in step (2) should be no less than 100 μm, and the maximum coating thickness should not exceed 250 μm.

[0012] Preferably, the corrosion protection of the petrolatum coating includes: uniformly applying the corrosion-resistant grease without exposing the original color of the workpiece; filling with putty, shaping the putty, filling it between the fasteners, and compacting it to make a smooth transition between the fasteners and the steel substrate; wrapping with anti-corrosion tape, ensuring at least two layers at each location; and after wrapping with the anti-corrosion tape, forcefully smoothing the anti-corrosion tape to remove any air pockets.

[0013] Preferably, the anti-corrosion paste is a base petroleum grease anti-corrosion paste with the addition of 10% calcium petroleum sulfonate and 2% barium petroleum grease soap.

[0014] Preferably, the basic petrolatum anti-corrosion paste comprises the following raw materials in parts by weight: 25-35 parts paraffin wax, 110-130 parts petrolatum, 13-19 parts organic bentonite, 10-14 parts lanolin, 5-7 parts trinonylnaphthalene barium sulfate, and 3-5 parts mica powder.

[0015] St2 is based on the national standard GB / T 8923.1-2011, "Visual Assessment of Surface Cleanliness of Steel Surfaces Before Coating - Part 1: Rust Grades and Treatment Grades of Uncoated Steel Surfaces and Steel Surfaces After Complete Removal of Existing Coatings." The specific surface treatment grades for steel before coating in the national standard are shown in Table 1. Existing coatings typically require surface treatment to reach St3 or higher before application. The anti-corrosion process in this application only needs to reach St2.

[0016] Table 1 Cleaning Levels for Hand and Power Tools Beneficial effects of the present invention 1. Simple process and low cost This invention discloses a method for corrosion protection of hollow steel pipe concrete poles. By sealing both ends of the inner steel pipe for physical isolation and corrosion protection, brushing anti-corrosion coating on the outer surface of the pole body, and locally covering the flange joints with petrolatum paste, the best anti-corrosion effect of the composite pole is achieved. This method avoids the problems of environmental pollution and poor anti-corrosion effect in heavily corrosive environments caused by traditional hot-dip galvanizing, while also reducing the cost of pole corrosion protection.

[0017] 2. The corrosion protection effect meets the requirements of national standards. This application improves the corrosion resistance of flange joints by adding 10% calcium petroleum sulfonate and 2% barium soap of oxidized petroleum grease to a base petroleum grease anticorrosion paste. In accordance with GB / T 10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", a neutral salt spray test was conducted on hot-dip galvanized samples, anticorrosion samples of composite poles, and samples coated with petroleum grease paste for bolt connections in a salt spray test chamber. After 240 hours of testing, rust spots appeared on the hot-dip galvanized samples. After 1000 hours of testing, no red rust, blistering, or peeling was observed on the surface of the anticorrosion coated samples. After 1000 hours of testing, no red rust appeared on the outer surface of the samples coated with petroleum grease paste for bolt connections. Upon removal, no rust was found at the bolt connections. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a hollow-core concrete pole structure. Figure 2 This is a picture of the anti-corrosion construction site. Detailed Implementation

[0019] This application relates to a method for corrosion protection of hollow-core steel-concrete composite utility poles, which will be explained in detail below through specific embodiments.

[0020] Example 1 For a certain 110kV transmission line with an atmospheric corrosion rating of C2, the corrosion protection of hollow steel pipe concrete poles includes pole body corrosion protection and joint corrosion protection; the specific method is to seal and isolate the two ends of the inner steel pipe for corrosion protection, and to apply anti-corrosion coating to the outside of the pole body and joints.

[0021] The primer used in this embodiment includes two components, A and B. Component A includes the following raw materials in parts by weight: 50 parts epoxy resin, 190 parts zinc powder, 4 parts rust conversion agent (equal weights of zinc chromate, aluminum tripolyphosphate and zinc phosphate), 2 parts BYK1681, 2 parts BYK110, 0.5 parts BYK-GO 8730, 20 parts xylene solvent, and 6 parts silane coupling agent. Component B is 50 parts ZY-2015C. The topcoat uses commercially available acrylic polyurethane topcoat.

[0022] The anti-corrosion coating application includes: surface treatment, wiping the surface of the steel components with a damp cloth to remove loose rust and dirt; for stubborn loose rust and dirt, a wire brush can be used to clean it until it reaches St2 or the original rust state; and then applying the anti-corrosion coating. The coating includes a primer and a topcoat, each composed of component A and component B, respectively. Before application, components A and B should be thoroughly mixed. The coating should be applied from top to bottom and from the inside out. Application methods include brushing, spraying, and rolling. Each coat should be applied after the previous coat has fully dried. The coating area covers the exposed steel of the pole, including the pole and flange joints.

[0023] The dry film thickness of the coating is not less than 100 μm, and the maximum coating thickness is not more than 150 μm.

[0024] The physical isolation corrosion protection of the inner steel pipe is achieved by using a thin steel plate to seal the through holes on the upper and lower flanges of the inner steel pipe with metal repair adhesive, so that the inner surface of the steel pipe is in a closed space, which isolates the inner surface of the steel pipe from the external corrosive environment. After sealing, the height of the thin steel plate shall not be higher than the height of the flange.

[0025] According to GB / T 10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", a neutral salt spray test was conducted on the anti-corrosion substitute sample of the composite pole (the anti-corrosion process is the same as in Example 1, and the dry film thickness of the coating is 105.2 μm) and the hot-dip galvanized sample (coating thickness is 88.7 μm) in a salt spray test chamber. After 264 hours of testing, rust spots appeared on the hot-dip galvanized sample. After 1000 hours of operation, the anti-corrosion substitute sample of the composite pole showed no red rust, blistering, or peeling on the coating surface.

[0026] The cost of hot-dip galvanizing steel components is approximately 1500 yuan / ton, and the cost of applying anti-corrosion coating is approximately 100 yuan / square meter. For a 110kV hollow-core steel-concrete tension pole, the steel weighs approximately 18.6 tons, and the outer surface area of ​​the pole is approximately 112 square meters. The anti-corrosion cost using the anti-corrosion method of this invention is approximately 40% of the cost of hot-dip galvanizing.

[0027] Example 2 For a certain 110kV transmission line with an atmospheric corrosion rating of C4, the corrosion protection of hollow steel pipe concrete poles includes pole body corrosion protection and joint corrosion protection. The specific methods are: sealing and isolating both ends of the inner steel pipe for corrosion protection, brushing anti-corrosion coating on the outside of the pole body, and brushing anti-corrosion coating on the joints.

[0028] The primer used in this embodiment includes two components, A and B. Component A includes the following raw materials in parts by weight: 40 parts epoxy resin, 250 parts zinc powder, 4 parts aluminum tripolyphosphate and zinc phosphate, 1 part BYK054, 1 part BYK110, 0.5 parts BYK-GO 8730, 5 parts n-butanol, 15 parts xylene, and 6 parts silane coupling agent. Component B is 50 parts ZY-2015C. The topcoat uses commercially available acrylic polyurethane topcoat.

[0029] The anti-corrosion coating application includes: surface treatment, wiping the surface of the steel components with a damp cloth to remove loose rust and dirt, and cleaning stubborn loose rust and dirt with a wire brush to achieve St2 or original rust condition; applying the anti-corrosion coating, which includes a primer and a topcoat, each composed of component A and component B respectively. Before application, components A and B should be stirred evenly. The coating should be applied from top to bottom and from inside to outside. Application methods include brushing, spraying, and rolling. Each coat should be applied after the previous coat has fully dried. The coating area covers the exposed steel on the outside of the pole, including the pole and flange joints.

[0030] The dry film thickness of the coating is not less than 100 μm, and the maximum coating thickness is not more than 150 μm.

[0031] The physical isolation corrosion protection of the inner steel pipe is achieved by using a thin steel plate to seal the through holes on the upper and lower flanges of the inner steel pipe with metal repair adhesive, so that the inner surface of the steel pipe is in a closed space, which isolates the inner surface of the steel pipe from the external corrosive environment. After sealing, the height of the thin steel plate shall not be higher than the height of the flange.

[0032] According to GB / T 10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", a neutral salt spray test was conducted on the anti-corrosion substitute of the composite pole (the anti-corrosion process is the same as in Example 2, and the dry film thickness of the coating is 103.5 μm) and the hot-dip galvanized sample (coating thickness is 86.9 μm) in a salt spray test chamber. After 246 hours of testing, rust spots appeared on the hot-dip galvanized sample. After 1000 hours of operation, the anti-corrosion substitute of the composite pole showed no red rust, blistering, or peeling on the coating surface.

[0033] The cost of hot-dip galvanizing steel components is approximately 1500 yuan / ton, and the cost of applying anti-corrosion coating is approximately 100 yuan / square meter. For a 110kV hollow-core steel-concrete tension pole, the steel weighs approximately 18.6 tons, and the outer surface area of ​​the pole is approximately 112 square meters. The anti-corrosion cost using the anti-corrosion method of this invention is approximately 40% of the cost of hot-dip galvanizing.

[0034] Example 3 For a coastal 110kV transmission line with an atmospheric corrosion rating of C5, the corrosion protection of hollow steel pipe concrete poles includes pole body corrosion protection and joint corrosion protection. The specific methods are: sealing and isolating both ends of the inner steel pipe for corrosion protection, brushing anti-corrosion coating on the outside of the pole body for corrosion protection, brushing anti-corrosion coating on the joint connection and then applying local petrolatum paste for corrosion protection.

[0035] The primer used in this embodiment includes two components, A and B. Component A includes the following raw materials in parts by weight: 30 parts epoxy resin, 280 parts zinc powder, 2 parts zinc chromate, 1 part BYK054, 1 part BYK1165, 1 part BYK410, 30 parts solvent (equal amounts of xylene and n-butanol), and 4 parts silane coupling agent. Component B is 30 parts ZY-2015C. The topcoat uses commercially available acrylic polyurethane topcoat.

[0036] The basic petrolatum corrosion inhibitor consists of: 35 parts paraffin, 110 parts petrolatum, 13 parts organic bentonite, 14 parts lanolin, 7 parts trinonylnaphthalene barium sulfate, and 3 parts mica powder.

[0037] The anti-corrosion coating application includes: surface treatment, wiping the surface of the steel components with a damp cloth to remove loose rust and dirt, and cleaning stubborn loose rust and dirt with a wire brush to achieve St2 or original rust condition; applying the anti-corrosion coating, which includes a primer and a topcoat, each composed of component A and component B respectively. Before application, components A and B should be stirred evenly. The coating should be applied from top to bottom and from inside to outside. Application methods include brushing, spraying, and rolling. Each coat should be applied after the previous coat has fully dried. The coating area covers the exposed steel on the outside of the pole, including the pole and flange joints.

[0038] The dry film thickness of the coating is not less than 120 μm, and the maximum coating thickness does not exceed 250 μm.

[0039] The physical isolation corrosion protection of the inner steel pipe is achieved by using a thin steel plate to seal the through holes on the upper and lower flanges of the inner steel pipe with metal repair adhesive, so that the inner surface of the steel pipe is in a closed space, isolating the inner surface of the steel pipe from the external corrosive environment. After sealing, the height of the thin steel plate shall not be higher than the height of the flange.

[0040] The petrolatum-based anti-corrosion coating includes: applying an anti-corrosion paste, which is a base petrolatum anti-corrosion paste with 10% calcium petroleum sulfonate and 2% oxidized petroleum ester barium soap added. The specific process is as follows: take a small amount of the anti-corrosion paste in the palm of your hand and spread it evenly on the surface of the flange joint after the anti-corrosion coating has been applied, ensuring the original color of the workpiece is not exposed. The amount of anti-corrosion paste used is 200g / m². 2 Left and right; Fill with putty, shape and fill the gaps between the fasteners, compact it to ensure a smooth transition between the fasteners and the steel substrate; Wrap with anti-corrosion tape, select an appropriate width of anti-corrosion tape according to the shape and size of the node, cut and wrap it around the outer surface of the node, ensuring at least two layers at each location. After wrapping the anti-corrosion tape, smooth it firmly to remove any air pockets.

[0041] According to GB / T 10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", neutral salt spray tests were conducted on hot-dip galvanized samples (coating thickness of 87.5 μm), anti-corrosion substitutes for composite poles (anti-corrosion process is the same as in Example 3, dry film thickness of coating is 121.8 μm), and substitutes for bolted connections coated with petrolatum (anti-corrosion process is the same as in Example 3) in a salt spray test chamber. After 240 hours of testing, rust spots appeared on the hot-dip galvanized samples. After 1000 hours of testing, no red rust, blistering, or peeling was observed on the surface of the anti-corrosion coated samples. After 1000 hours of testing, no red rust appeared on the outer surface of the bolted connections coated with petrolatum. Upon disassembly, no rust was found at the bolted connections.

[0042] The cost of hot-dip galvanizing steel components is approximately 1500 yuan / ton, the cost of applying anti-corrosion coating is approximately 120 yuan / square meter, and the cost of petrolatum coating is approximately 100 yuan / square meter. For a 110kV hollow-core steel-concrete terminal pole, the steel weighs approximately 17.1 tons, the outer surface area of ​​the pole is approximately 104 square meters, and the petrolatum coating area is approximately 10 square meters. The anti-corrosion cost using the anti-corrosion method of this invention is approximately 52% of the cost of hot-dip galvanizing.

[0043] Example 4 For a 110kV transmission line in a coastal heavy industrial area, the atmospheric corrosion level is C5. The corrosion protection of the hollow steel pipe concrete poles includes pole body corrosion protection and joint corrosion protection. The specific methods are: sealing and isolating both ends of the inner steel pipe for corrosion protection, brushing anti-corrosion coating on the outside of the pole body for corrosion protection, brushing anti-corrosion coating on the joint connection and then applying local petrolatum paste for corrosion protection.

[0044] The primer used in this embodiment includes two components, A and B. Component A includes the following raw materials in parts by weight: 30 parts epoxy resin, 240 parts zinc powder, 3 parts rust conversion agent (equal weights of zinc chromate, aluminum tripolyphosphate and zinc phosphate), 2 parts BYK054, 1 part BYK110, 1 part BYK-GO 8730, 17 parts xylene, 7 parts n-butanol, and 5 parts silane coupling agent. Component B is 30 parts ZY-2015C. The topcoat uses commercially available acrylic polyurethane topcoat.

[0045] The basic petrolatum corrosion inhibitor consists of: 30 parts paraffin, 120 parts petrolatum, 16 parts organic bentonite, 12 parts lanolin, 6 parts trinonylnaphthalene barium sulfate, and 4 parts mica powder.

[0046] The anti-corrosion coating application includes: surface treatment, wiping the surface of the steel component with a damp cloth to remove loose rust and dirt; for stubborn loose rust and dirt, a wire brush can be used to clean it until it reaches St2 or the original rust state; applying the anti-corrosion coating, which includes a primer and a topcoat, each composed of component A and component B respectively. Before application, components A and B should be thoroughly mixed. The coating should be applied from top to bottom and from the inside out. Application methods include brushing, spraying, and rolling. Each coat should be applied after the previous coat has fully dried. The coating area covers the exposed steel of the pole, including the pole and flanges. Preferably, the dry film thickness of the coating is not less than 120 μm, and the maximum coating thickness does not exceed 200 μm.

[0047] The physical isolation corrosion protection of the inner steel pipe is achieved by using a thin steel plate to seal the through holes on the upper and lower flanges of the inner steel pipe with metal repair adhesive, so that the inner surface of the steel pipe is in a closed space, isolating the inner surface of the steel pipe from the external corrosive environment. After sealing, the height of the thin steel plate shall not be higher than the height of the flange.

[0048] The petrolatum-based anti-corrosion coating includes: applying an anti-corrosion paste, which is a base petrolatum anti-corrosion paste with 10% calcium petroleum sulfonate and 2% oxidized petroleum ester barium soap added. The specific process is as follows: take a small amount of the anti-corrosion paste in the palm of your hand and spread it evenly on the surface of the flange joint after the anti-corrosion coating has been applied, ensuring the original color of the workpiece is not exposed. The amount of anti-corrosion paste used is 200g / m². 2Left and right; Fill with putty, shape and fill the gaps between the fasteners, compact it to ensure a smooth transition between the fasteners and the steel substrate; Wrap with anti-corrosion tape, select an appropriate width of anti-corrosion tape according to the shape and size of the node, cut and wrap it around the outer surface of the node, ensuring at least two layers at each location. After wrapping the anti-corrosion tape, smooth it firmly to remove any air pockets.

[0049] According to GB / T 10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", a neutral salt spray test was conducted on hot-dip galvanized samples (coating thickness of 86.5 μm), anti-corrosion substitutes for composite poles (anti-corrosion process is the same as in Example 4, dry film thickness of coating is 123.3 μm), and substitutes for bolted connections coated with petrolatum (anti-corrosion process is the same as in Example 4) in a salt spray test chamber. After 248 hours of testing, rust spots appeared on the hot-dip galvanized samples. After 1000 hours of testing, the surface of the coated samples showed no red rust, blistering, or peeling. After 1000 hours of testing, no red rust appeared on the outer surface of the bolted connections coated with petrolatum. After peeling them off, no rust was found at the bolt connections.

[0050] The cost of hot-dip galvanizing steel components is approximately 1500 yuan / ton, the cost of applying anti-corrosion coating is approximately 120 yuan / square meter, and the cost of petrolatum coating is approximately 100 yuan / square meter. For a 110kV hollow-core steel-concrete terminal pole, the steel weighs approximately 17.1 tons, the outer surface area of ​​the pole is approximately 104 square meters, and the petrolatum coating area is approximately 10 square meters. The anti-corrosion cost using the anti-corrosion method of this invention is approximately 52% of the cost of hot-dip galvanizing.

[0051] Comparative Example 1 For a 110kV transmission line in a coastal heavy industrial area, the atmospheric corrosion level is C5. The corrosion protection of the hollow steel pipe concrete poles includes pole body corrosion protection and joint corrosion protection. The specific methods are: sealing and isolating both ends of the inner steel pipe for corrosion protection, brushing anti-corrosion coating on the outside of the pole body for corrosion protection, brushing anti-corrosion coating on the joint connection and then applying local petrolatum paste for corrosion protection.

[0052] The primer used in this comparative example consists of two components, A and B. Component A includes the following raw materials in parts by weight: 30 parts epoxy resin, 240 parts zinc powder, 3 parts rust conversion agent (equal weights of zinc chromate, aluminum tripolyphosphate and zinc phosphate), 2 parts BYK054, 1 part BYK110, 1 part BYK-GO 8730, 17 parts xylene, 7 parts n-butanol, and 5 parts silane coupling agent. Component B consists of 30 parts ZY-2015C. The topcoat uses commercially available acrylic polyurethane topcoat.

[0053] The petrolatum-based anti-corrosion coating includes: applying an anti-corrosion paste, which is a base petrolatum anti-corrosion paste (comprising: 30 parts paraffin wax, 120 parts petrolatum, 16 parts organobentonite, 12 parts lanolin, 6 parts trinonylnaphthalene barium sulfate, and 4 parts mica powder). The specific process is as follows: take a small amount of the anti-corrosion paste in the palm of your hand and spread it evenly on the surface of the flange joint after the anti-corrosion coating has been applied, ensuring the original color of the workpiece is not exposed. The amount of anti-corrosion paste used is approximately 200 g / m². 2 Left and right; Fill with putty, shape and fill the gaps between the fasteners, compact it to ensure a smooth transition between the fasteners and the steel substrate; Wrap with anti-corrosion tape, select an appropriate width of anti-corrosion tape according to the shape and size of the node, cut and wrap it around the outer surface of the node, ensuring at least two layers at each location. After wrapping the anti-corrosion tape, smooth it firmly to remove any air pockets.

[0054] The remaining implementation methods are the same as in Example 4.

[0055] According to GB / T 10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", a neutral salt spray test was conducted on hot-dip galvanized samples (coating thickness of 86.5 μm), anti-corrosion substitutes for composite poles (anti-corrosion process is the same as in Example 4, dry film thickness of coating is 123.3 μm), and substitutes for bolted connections coated with petrolatum paste (anti-corrosion process is brushing on anti-corrosion coating and then applying localized and uniform anti-corrosion paste) in a salt spray test chamber. After 248 hours of testing, rust spots appeared on the hot-dip galvanized samples. After 1000 hours of testing, the coating surface of the brushed anti-corrosion coating samples showed no red rust, blistering, or peeling. After 1000 hours of testing, a small number of rust spots were found at the bolt corners of the bolt connections when the samples were peeled off.

[0056] The cost of hot-dip galvanizing steel components is approximately 1500 yuan / ton, the cost of applying anti-corrosion coating is approximately 120 yuan / square meter, and the cost of petrolatum coating is approximately 95 yuan / square meter. For a 110kV hollow-core steel pipe concrete terminal pole, the steel weighs approximately 17.1 tons, the outer surface area of ​​the pole is approximately 104 square meters, and the petrolatum coating area is approximately 10 square meters. The anti-corrosion cost using the anti-corrosion method of this invention is approximately 52% of the cost of hot-dip galvanizing.

[0057] Comparative Example 2 For a 110kV transmission line in a coastal heavy industrial area, the atmospheric corrosion level is C5. The corrosion protection of the hollow steel pipe concrete poles includes pole body corrosion protection and joint corrosion protection. The specific methods are: sealing and isolating both ends of the inner steel pipe for corrosion protection, brushing anti-corrosion coating on the outside of the pole body for corrosion protection, brushing anti-corrosion coating on the joint connection and then applying local petrolatum paste for corrosion protection.

[0058] The primer used in this comparative example consists of two components, A and B. Component A includes the following raw materials in parts by weight: 30 parts epoxy resin, 240 parts zinc powder, 3 parts rust conversion agent (equal weights of zinc chromate, aluminum tripolyphosphate and zinc phosphate), 2 parts BYK054, 1 part BYK110, 1 part BYK-GO 8730, 17 parts xylene, 7 parts n-butanol, and 5 parts silane coupling agent. Component B consists of 30 parts ZY-2015C. The topcoat uses commercially available acrylic polyurethane topcoat.

[0059] The basic petrolatum corrosion inhibitor consists of: 30 parts paraffin, 120 parts petrolatum, 16 parts organic bentonite, 12 parts lanolin, 6 parts trinonylnaphthalene barium sulfate, and 4 parts mica powder.

[0060] The petrolatum-based anti-corrosion coating includes: applying an anti-corrosion paste, which is a base petrolatum anti-corrosion paste with 10% calcium petroleum sulfonate added. The specific process is as follows: take a small amount of the anti-corrosion paste in the palm of your hand and spread it evenly on the surface of the flange joint after the anti-corrosion coating has been applied, ensuring the original color of the workpiece is not exposed. The amount of anti-corrosion paste used is 200g / m². 2 Left and right; Fill with putty, shape and fill the gaps between the fasteners, compact it to ensure a smooth transition between the fasteners and the steel substrate; Wrap with anti-corrosion tape, select an appropriate width of anti-corrosion tape according to the shape and size of the node, cut and wrap it around the outer surface of the node, ensuring at least two layers at each location. After wrapping the anti-corrosion tape, smooth it firmly to remove any air pockets.

[0061] According to GB / T 10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", a neutral salt spray test was conducted on hot-dip galvanized samples (coating thickness of 86.5 μm), anti-corrosion substitutes for composite poles (anti-corrosion process is the same as in Example 4, dry film thickness of coating is 123.3 μm), and substitutes for bolted connections coated with petrolatum paste (anti-corrosion process is brushing on anti-corrosion coating and then applying localized and uniform anti-corrosion paste) in a salt spray test chamber. After 248 hours of testing, rust spots appeared on the hot-dip galvanized samples. After 1000 hours of testing, the coating surface of the brushed anti-corrosion coating samples showed no red rust, blistering, or peeling. After 1000 hours of testing, a small number of rust spots were found at the bolt corners of the bolt connections when the samples were peeled off.

[0062] The cost of hot-dip galvanizing steel components is approximately 1500 yuan / ton, the cost of applying anti-corrosion coating is approximately 120 yuan / square meter, and the cost of petrolatum coating is approximately 95 yuan / square meter. For a 110kV hollow-core steel pipe concrete terminal pole, the steel weighs approximately 17.1 tons, the outer surface area of ​​the pole is approximately 104 square meters, and the petrolatum coating area is approximately 10 square meters. The anti-corrosion cost using the anti-corrosion method of this invention is approximately 52% of the cost of hot-dip galvanizing.

Claims

1. A method for corrosion protection of hollow-core steel-concrete composite utility poles, characterized in that, This includes corrosion protection for the pole body and corrosion protection for the joints; the corrosion protection for the pole body includes corrosion protection for the outer steel pipe and corrosion protection for the inner steel pipe. (1) Surface treatment: The surface treatment of steel components shall reach St2 or the original rust state; (2) The corrosion protection of the outer steel pipe is achieved by brushing anti-corrosion coating: the coating is applied from top to bottom and from inside to outside; (3) The corrosion protection of the inner steel pipe is to seal both ends of the inner steel pipe and physically isolate the external corrosive factors: use thin steel plate to seal the through holes on the upper and lower flanges of the inner steel pipe with metal repair glue, so that the inner surface of the steel pipe is in a closed space and the inner surface of the steel pipe is isolated from the external corrosive environment. After sealing, the height of the thin steel plate shall not be higher than the height of the flange. (4) The node corrosion protection includes: applying anti-corrosion coating in atmospheric corrosion environment of C1-C4 level; applying anti-corrosion coating in atmospheric corrosion environment of C5 and above level and then applying local petrolatum paste for corrosion protection; The corrosion protection process of the petrolatum coating includes: uniformly applying the corrosion-resistant paste without exposing the original color of the workpiece; filling with putty, shaping the putty, filling it between the fasteners, and compacting it to make a smooth transition between the fasteners and the steel substrate; wrapping with anti-corrosion tape, ensuring at least two layers in each part; and after wrapping with anti-corrosion tape, pressing the anti-corrosion tape firmly to remove any air. The corrosion-resistant grease is made by adding 10% calcium petroleum sulfonate and 2% barium petroleum oxidized soap to a base petroleum grease corrosion-resistant grease.

2. The corrosion protection method for hollow sandwich steel pipe concrete poles according to claim 1, characterized in that, The anti-corrosion coating used in step (2) or step (4) includes a primer and a topcoat. The primer includes two components, A and B. Component A includes 30-50 parts of epoxy resin, 190-280 parts of zinc powder, 2-4 parts of rust conversion agent, 1-2 parts of defoamer, 1-2 parts of dispersant, 0.5-1 part of leveling agent, 20-30 parts of solvent, and 4-6 parts of silane coupling agent. Component B is 30-50 parts of curing agent.

3. The corrosion protection method for hollow sandwich steel tube concrete poles according to claim 2, characterized in that, The corrosion conversion agent is one or more of zinc chromate, zinc phosphate, and aluminum tripolyphosphate.

4. The corrosion protection method for hollow sandwich steel tube concrete poles according to claim 2, characterized in that, The solvent is xylene and / or n-butanol.

5. The corrosion protection method for hollow sandwich steel tube concrete poles according to claim 1, characterized in that, In step (2), the maximum thickness of the anti-corrosion coating should not exceed 250 μm, and the thickness of the dry film formed after the anti-corrosion coating dries should not be less than 100 μm.

6. The corrosion protection method for hollow sandwich steel tube concrete poles according to claim 1, characterized in that, The basic petrolatum anti-corrosion paste comprises the following raw materials in parts by weight: 25-35 parts paraffin wax, 110-130 parts petrolatum, 13-19 parts organic bentonite, 10-14 parts lanolin, 5-7 parts trinonylnaphthalene barium sulfate, and 3-5 parts mica powder.

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