Galvanized Steel

Hot-dip galvanizing (DIN EN ISO 1461) involves immersing steel in molten zinc at approximately 450 degrees Celsius, producing a thick, durable coating of 45-85 micrometres. Electro-galvanizing applies a thinner zinc layer (5-25 micrometres) through an electrochemical process. For structural and outdoor applications, hot-dip galvanized steel is strongly recommended due to its significantly longer service life and self-healing zinc-iron alloy layers.

The lifespan depends on the corrosivity category of the environment (EN ISO 9223). In a rural or suburban atmosphere (C2), hot-dip galvanized steel can last 50-100 years. In an industrial or coastal environment (C4), it typically lasts 25-40 years. Even in severe marine conditions (C5), galvanized coatings provide 15-25 years of protection before first maintenance is needed.

Yes, galvanized steel can be welded, but it requires specific precautions. The zinc coating must be removed in the weld zone (typically 10-25 mm from the joint), proper ventilation must be ensured, and after welding the affected area should be restored with zinc-rich paint or spray galvanizing. ULAMEX supplies galvanized products intended for bolted and welded structural connections.

The primary standard is DIN EN ISO 1461, which specifies minimum zinc coating thicknesses based on the material thickness of the galvanized component. For continuously galvanized steel strip and sheet, the relevant standard is EN 10346, which defines coating classes such as Z275, Z350 and Z450. For galvanized tubes, EN 10240 applies.

The number refers to the total zinc mass in grams per square metre on both sides of the steel. Z275 means 275 g/m2 (approximately 20 micrometres per side), Z350 means 350 g/m2 (25 micrometres per side), and Z450 means 450 g/m2 (32 micrometres per side). Higher coating classes provide greater corrosion resistance for more demanding environments.

The choice depends on the application. Galvanized steel offers excellent corrosion resistance at a lower cost and is ideal for structural, outdoor and agricultural applications. Stainless steel provides superior resistance to chemicals, high temperatures and aesthetic requirements (food processing, architecture, marine). For most construction and infrastructure projects, hot-dip galvanized steel is the more cost-effective solution.

White rust (zinc hydroxide/zinc carbonate) is a white, powdery deposit that can form on newly galvanized surfaces when moisture is trapped between stacked galvanized components. It is superficial and does not affect the long-term corrosion protection. Proper storage with adequate ventilation and spacing between components prevents white rust formation.

Yes. ULAMEX delivers galvanized profiles, fences, gratings and wire products to over 20 European countries. We maintain warehouse stock for prompt dispatch and provide full transportation logistics. Request a quote to receive availability, lead times and delivered pricing for your project.