Reasons for Rusting of Container Houses
The main reason for rusting of container houses is the chemical reaction between steel and moisture, oxygen, and other corrosive substances in the surrounding environment, leading to metal corrosion. Specific reasons are as follows:
Environmental factors: If container houses are in humid environments for a long time, such as coastal areas, rainy regions, or industrial zones with high humidity, the moisture in the air reacts with the iron on the surface of the steel to form iron oxide (rust). In addition, the chloride ions in the sea salt mist accelerate the corrosion of the steel, forming electrochemical rusting and speeding up the rusting process.
Inadequate anti-corrosion processes: If effective anti-corrosion processes, such as hot-dip galvanizing or high-quality anti-corrosion paint spraying, are not adopted during the manufacturing of container houses, the corrosion resistance of the steel will be significantly reduced. Hot-dip galvanizing forms a zinc layer by immersing the steel in a zinc bath, which can effectively isolate moisture and oxygen, but it is costly. Anti-corrosion paint spraying requires multiple layers of spraying, and the thickness and quality of the paint film directly affect the anti-corrosion effect. If the anti-corrosion process is not in place or only simple painting is done, the steel is prone to rusting.
Service life and maintenance: Although the design life of container houses can reach more than 20 years, after long-term use, the protective layer on the surface of the steel may fail due to wear, aging, or mechanical damage, allowing water and oxygen to penetrate and cause rusting. Regular inspection and maintenance, such as repainting or replacing damaged parts, are crucial for extending the service life. If maintenance is neglected, the rusting will gradually expand and may even lead to structural damage.
Design flaws: If the drainage system of container houses is not reasonably designed, such as having no slope in the gutter or a blocked outlet, rainwater may accumulate on the roof or at structural joints, soaking the steel for a long time and accelerating corrosion. In addition, improper waterproofing at the openings on the roof or walls can also be the starting point for rusting.
