First, the application of anti-corrosion coating. Steel structure plants, steel box girder bridges, TV towers, building antennas, transmission substations, steel poles and other outdoor steel structures, which are subject to climate change, sun and rain, and the surface is quickly oxidized due to prolonged exposure to the atmosphere. The formation of a layer of ferric oxide seriously affects the strength and service life of the steel structure. In order to prevent the oxidation of the surface of the steel structure, paint protection has generally been used in the past, and its anti-corruption period is generally 3-5 years, so it requires regular maintenance, Maintenance, the common method is to copy shovel paint, cost a lot of manpower and material resources. Now use steel surface spray zinc, aluminum spray process to protect, anti-corrosion life of up to 30 years without maintenance. Such as zinc-aluminum coating plus paint closure , the antiseptic is longer. The surface of the steel structure can only play the role of anode protection after zinc spraying and aluminum spraying, so as to achieve the purpose of long-term corrosion protection of steel structures. Therefore, many major projects and municipal projects in the country have been designated to adopt the technology. For example: the Yangtze River Three Gorges longer gate , Shanghai Oriental Pearl TV Tower, Yangpu Bridge main guardrail, Guangzhou city's inner ring elevated steel beam, steel antenna of Shanghai Securities Building, Pudong Airport Road Gonggou gas explosion pipeline, Shanghai South Bridge 500,000 kilowatts substation, etc., to ensure major projects Centennial plan. Second, anti-water corrosion coating. The steel sluice gate is the main steel structure controlling the water volume in the hydroelectric power station and reservoir. It is partially submerged in water for a long time. The surface is subject to microbial attack (such as adsorption of nail rakes, and its excrement is acidic). The other part is exposed to the atmosphere for a long period of time. In particular, the waterline part is affected by surfing and floating objects on the water surface, and at the same time, it is affected by high tides and low tides, which makes the surface of this part of the steel structure often wet and dry alternately, and is particularly prone to rust. Now the wire is used for zinc spraying and aluminum spraying. The process greatly improves the corrosion resistance of the steel gate, which is 5 to 6 times longer than the original paint process. Third, spray zinc, aluminum spray process and similar process performance comparison (hot dip galvanizing process) 1, hot dip galvanizing process pretreatment using pickling, phosphating process, the workpiece surface will have acid, lye residue, leaving the hidden danger of corrosion, so that the hot dip galvanized layer is easy to fall off. Spray zinc, aluminum spray process Pretreatment adopts sandblasting process, so the surface of the workpiece is very clean and rough, the surface is sprayed with zinc, there is no corrosion from inside to outside after sprayed with aluminum, so it will not produce zinc layer shedding phenomenon. 2, hot dip galvanizing process has a certain temperature, about 440 °C or so, so the workpiece will be deformed after hot-dip; and spray zinc, aluminum spraying process is very low temperature, the workpiece surface temperature <80 °C, so the workpiece is not deformed . 3, the use of hot-dip galvanizing process, the workpiece by the plating tank length × width × height restrictions; while the use of zinc spray, aluminum spray process without restrictions on the workpiece. 4, using hot-dip galvanizing process, there are still field repair problems. On-site installation, weld, loading and unloading, transportation damage, repair can only use paint, resulting in a breakthrough process. If using zinc spray, aluminum spray process, the scene Can use zinc spray, aluminum spray method to repair, to avoid a breakthrough process. 5. As the pretreatment of the hot-dip galvanizing process adopts pickling and phosphating, the surface of the workpiece has no roughness and poor adhesion of the coating. The pretreatment of the zinc spray and aluminum spray process adopts sand blasting, Sa ≥ 2.5 grade. Therefore, the workpiece surface roughness, coating adhesion is better. Tensile strength ≥ 0.6kg/mm2. 6, hot-dip galvanizing process is very serious pollution of water quality, environmental protection issues are very prominent. So thermal spray zinc, aluminum spray process in more and more widely.