Electro-Galvanizing vs Hot-Dipped Galvanizing

Galvanized steel is coated with zinc to create a physical and chemical barrier that prevents corrosion. Galvanized steel has a longer lifespan and reduced maintenance costs over its life.

There are two types of Galvanized steel available, Hot-dipped and Electro-galvanized. The major difference between these two types is the production method.

Hot-dipped galvanized steel is dipped into a vat of molten zinc, which coats the steel. The galvanized steel is removed and allowed to cool. Structural shapes such as angles and channels are frequently hot-dipped. Hot-dip galvanization yields a strong, thick coating but generally has a dull gray finish. Hot-dip galvanization is known to have a very long life averaging between 20 to 50 years.

As its name indicates, Electro-galvanized steel is a plating process where the steel is placed in an electrically charged solution of zinc and saline. This causes the zinc to chemically bond to the conductive steel. Electro-plating is frequently used for coiled sheet steel, which is later formed into shapes such as c-purloins, and corrugated sheets or can be formed and welded into pipes and tubes. Often a UV-resistant polymer is applied after electro-plating to further protect the steel and provide a paintable surface that does not need to be primed. Generally, the layer formed by electro galvanization is extremely thin; hence the life expectancy of the layer is less than that of hot dipped material.

Manufacturers galvanize products in different ways to accommodate their intended purpose. Building materials designed for structural support are commonly hot-dipped to ensure durability and longevity. Products that are easily replaceable, like outdoor furniture and gardening tools, are more likely to be electro galvanized.

There are key factors to consider when choosing between electro-galvanized and hot dip galvanized products. For example, you can evaluate the physical location that the product will inhabit. Prolonged exposure to direct sunlight, moisture, and fallen debris from overhead trees will promote the effects of corrosion. Determine the item’s purpose. An ornamental item would not require the same level of protection as a structural item.