The Hazards of Rust, Traditional Rust Removal Methods, and the Characteristics and Applications of Rust Converters

We are all familiar with the formation of rust. Essentially, rust is the result of iron reacting with oxygen and water vapour in the air to form hydrated compounds of various iron oxides. The composition of rust is relatively complex and is usually represented simply as Fe₂O₃·xH₂O. Rust is a brittle, porous substance that fails to protect the underlying iron from corrosion. Consequently, over time, steel products may corrode into a pile of useless scrap. It is precisely for this reason that rust removal from metal surfaces is an essential step prior to anti-corrosion coating. With effective rust removal, surface protection can generally last for 5–6 years; however, if the surface is not properly treated, protection lasts only 4–6 months.

In the past, the rust removal methods we used included physical methods such as sanding with sandpaper and borax, as well as chemical methods such as electrolytic rust removal. However, in the last two years, a much-hyped rust remover has emerged, touted as ‘two-in-one’ or ‘three-in-one’, offering rust removal and protection in a single step. This product not only removes rust but also forms a protective film whilst doing so; in fact, it even eliminates the need for paint. This rust converter reduces the labour intensity of rust removal, extends the service life of the coating, and minimises the frequency of maintenance and the associated workload. It is particularly suitable for large-scale outdoor steel structures, where the sheer size of the structure makes surface preparation difficult; the rust converter is ideal for priming such large outdoor steel structures.

The key feature of this rust converter is that, for steel surfaces that have already rusted, there is no need for surface preparation such as grinding or sandblasting. Simply apply the rust converter directly to the rusted surface, where it will react chemically with the rust, converting it into a stable, protective black complex that becomes an integral part of the primer. Rust converters are widely used for anti-corrosion treatment on rusted surfaces of large metal steel structures, storage tanks, bridges, pipelines and similar applications.