1. The impact of the natural environment (different regions)
The selection of color-coated steel plates in different regions mainly considers the local wind and snow loads and corrosive environment. The wind and snow load is mainly considering the safety factor of the building. Although it is related to the mechanical properties of the color-coated steel plate, it is more related to the shape and thickness of the profiled steel plate and the connection between the plates.
It is relatively difficult to quantitatively describe the corrosion environment in an area, and there are many factors affecting the corrosion of color-coated steel plates. Such as: temperature, humidity, temperature difference between day and night, sunshine time and sunshine intensity, rainfall and acidity of rain, wind direction and speed, corrosive sediments, etc.
Elements of anti-corrosion effect of color-coated steel plate
They are coating type, coating thickness, coating supplier, coating type, coating thickness, pretreatment type, steel plate thickness, coating structure, etc.
Impact of construction design on corrosion
Installation or processing quality: it mainly reflects whether the coating is damaged during processing, whether it is processed when the coating is brittle at low temperature, the steel plate is damaged during installation, and the structural welding iron chips fall on the coating during installation. Cleaning the roof panel, etc., will cause corrosion of the material.
From so many introductions to the corrosion factors of color-coated steel plates, as well as the feedback of our users’ usage and the analysis of the results of exposure tests, our recommendations for use in different regions are as follows:
In plateaus with strong ultraviolet rays (southwest and northwest) and low latitudes (guangdong and south), consider color-coated steel plates with coatings with superior durability (PVDF coating, HDP coating, SMP coating, etc.). For high-humidity areas (most parts of the southern coast), coatings and coatings must be made of materials with excellent corrosion resistance, and the coating thickness and coating thickness must at least meet the requirements of national standards.
The use of color-coated steel plates at the seaside requires thick-coated color-coated steel plates or relatively dense coating varieties, because the chloride ion in seawater has a strong penetration ability, it can directly corrode through thin coatings or non-dense coatings The substrate coating, of course, the substrate must be galvanized or aluminum-zinc-plated material. Where the seawater can splash, it is not recommended to use color-coated steel plates.
In an industrial environment, the impact on color coating is mainly acid rain. These areas are concentrated in Hunan, Chongqing, Jiangxi and other areas. In connection with color coating using high zinc layer galvanized substrates, the color coating still needs to be thick and dense. In other areas that do not belong to the above-mentioned areas, the choice of using color-coated steel plates is relatively large, as long as they meet the national standards for color coating.
2. The impact of the use environment (different industries)
The use of color-coated steel plates in different industries is analyzed in two aspects. One is the outer plate of color-coated steel plates. Under normal circumstances, it is sufficient to choose according to different regions, but also to consider the impact of small environments, that is, whether there is corrosion in the vicinity The medium falls on the building envelope, such as the gas emitted by the boiler, sulfur dioxide dust, etc. This should be considered in the design of the height of the chimney and the main local wind direction.
In addition, there is also the tightness of the plant, it is also possible that the high temperature and humidity in the plant
Corrosive gas comes out and meets cold air outdoors to condense on the color-coated steel plate. This phenomenon should be avoided. It will accelerate the generation of local corrosion; Steel plate) or back paint (single-layer board). What needs to be explained here is that the inner panel of the roof is relatively easier to corrode than the inner panel of the wall. If workers can work in this environment, it is possible to use color-coated steel plates. However, the quality of the indoor environment or the investment of environmental protection devices will directly affect the service life of the painted steel plate.
Non-ferrous metal smelters (copper, zinc, aluminum, lead, etc.) are the most challenging years for color-coated steel plates. However, reasonable selection of materials, design, and environmental protection investment can ensure or increase the service life of color-coated steel plates. Replacement or maintenance can be done within 10 years. Iron and steel plants, power plants, etc. also produce corrosive media, but color-coated steel plates have long-term experience.
The machinery manufacturing industry (automobiles, steam turbines, machine tools, etc.) will basically not have a negative impact on the color coating corrosion, but it should be noted that these industries may have heat treatment furnaces, boilers, etc., which will also affect the local environment. Corrosion of coated steel plates, especially at processing damages or trims.
The industry of warehousing and logistics is developing rapidly, and the use of light steel is the most. It does not corrode the color-coated steel plate itself. Its selection of color-coated steel plate mainly considers the impact of the environment. Generally, such projects are concentrated in places with developed industries and heavy traffic , That is, the industrial environment and coastal areas.
The appearance and durability of public and civil buildings are the primary considerations for color-coated steel plates. Therefore, it is very important that the coating is resistant to discoloration, powdering, and the surface of the coating is complete and delicate. There are many people in public and civil buildings concerned, and they are close. Therefore, the choice of paint is generally PVDF or HDP, and light colors are mostly selected.
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