Galvanized Steel and How It Works

Our Light Duty Boltless Storage Racks are made of Galvanized Steel to ensure product durability and corrosion protection. Despite the fact that hot-dip galvanization was first practiced in the 17th century and subsequently widely applied by many industries, galvanized steel remains a mystery to many modern consumers.

What is Hot-dip Galvanizing?

The Galvanizing Process - - SIM WIN LIANG Singapore

Hot-dip galvanizing involves the immersion of steel work-pieces into a bath of molten zinc heated to a temperature of approximately 840 F. The zinc alloys with the surface of the base metal to form a protective finish. The zinc reacts with the oxygen in the atmosphere to form zinc oxide. The most important benefit of hot-dip galvanization is enhanced protection against corrosion.

Difference between Galvanizing and Powder Coating

A primary difference between galvanization and powder coating is the way they protect the surface of the work-piece. Galvanization provides sacrificial protection, meaning the finish will absorb corrosive materials before they can reach the metal object. Powder coating works by forming a protective barrier that prevents destructive materials from penetrating and reaching the surface. However, powder coating is porous and can easily damage under force or hard scratches. Once penetrated, the corrosion resistance is compromised and moisture and humidity can reach the underlying layer of metal easily. It is this very reason why users often find their metal racks corroding and rusting beneath the layer of powder-coat, that is supposed to protect it.

In Singapore, this is important as our humidity is relatively high and our storage racks are often in locations such as homes, bomb shelters, offices, retail shopping malls and industrial warehouses. With galvanized steel as the underlying material, even with no powder-coat or if the powder-coat is scratched, the underlying metal will not rust easily and spread internally beneath the layer of powder-coat.

Benefits of Galvanized Steel

  • Less Maintenance Required – Self-maintaining and thicker, resulting in maintenance cost of steel items is inevitably lower.
  • Longer Life – Under normal atmospheric condition, it can last in excess of 10 - 20 years, continually protecting steel against corrosive elements.
  • Lower Costs – Lower initial cost than a lot of other commonly specified corrosion protection coatings for steel, such as Stainless Steel.
  • Environmentally Friendly – The longevity of the maintenance-free coating provides environmental and economic benefits. Zinc exists naturally in the world so the zinc byproducts released into the atmosphere are not harmful.

Using Galvanization and Powder Coating Together

It’s possible to combine hot-dip galvanizing with powder coating to form a duplex system for protecting metal materials. The galvanized zinc serves as a base finish that enhances corrosion protection. The powder coating provides a top layer that slows down the rate in which corrosion consumes the underlying zinc. The powder coating can also improve the aesthetic appeal of the metal object.

January 31, 2020