For those trying to choose an appropriate silo, it may be useful to understand the differences between a galvanized steel silo and a carbon steel silo with food paint.
Galvanized silo.
Galvanization is the process of applying a protective zinc coating to steel in order to prevent rusting. A thicker coating results in a longer lifespan for the steel.
In the market, you will find silo manufacturer using different Zinc coatings: Z-275, Z-375, Z-450, Z-600. The number represents the grams of zinc per square meter that the steel has in both sides (inner and outer faces).
For instance, the Z-600 coating contains 600 gr/m2 of Zinc and is equivalent to a thickness of 42 micras per side which makes it longer-lasting even in the most aggressive of atmospheres (as established in Standard ISO 9223).
Silos Spain takes it a step further, predominantly using sheet metal with an innovative metal coating called ProMag in our silo manufacturing. ProMag is a revolutionary alloy of aluminum, magnesium and zinc delivering exceptional protection in the harshest conditions and extending the material’s lifespan significantly. It offers excellent corrosion resistance, up to 10 times more than galvanised steel and nearly 5 times more than Z-600 galvanised steel (600gr/m2).
Painted carbon steel silo.
In the market, you’ll find various solutions, with the most common being plastic paint and epoxy paint. While epoxy paint contains a high zinc content, neither option is as robust as galvanized steel.
Due to the substantial investment required for a storage silo project, the high cost of painting the entire surface (labor, raw materials, extended installation time), the complexity of applying multi-layer paint, reduced final quality, and shorter service life of painted steel, we do not recommend this solution.
Painting should only be used as a maintenance system in case of rust formation.