About Galvanizing
People ask us many questions
about galvanizing so here is a quick FAQ. If you want to learn more
you can always do a search on your favorite search engine.
Q. What is hot-dipped galvanizing? A. Hot-dipped galvanizing is a two part process. First the steel is cleaned by being dipped into several baths of different chemicals to prep the surface. Then it is placed in a bath of molten zinc, removed and allowed to dry.
Q. Yeah so what does that do for the steel? A. The zinc reacts with the steel to form several layers, which are different mixtures of steel and zinc. These layers “sacrifice” themselves to the elements but at a rate that is far slower than the steel itself. These layers bond to the steel with an adhesion strength greater than 3500 pounds per square inch! In fact some of these layers are almost twice as hard as the steel itself. This makes the galvanizing extremely tough and less likely to be damaged unlike other coatings.
Q. Is it not true that in a salt spray test galvanizing doesn't hold up as well as other coatings? A. Yes this is true. However, a salt spray test is used to "accelerate nature" in order to make 25 days seem more like 25 years. A salt spray test is conducted by subjecting an item to a continuous salt spray until rust occurs. This continuous spray in effect “rubs off” the protective zinc coating. In actuality galvanizing performs extremely well when allowed to go through wet and dry cycles which much more closely represents nature. In fact galvanizing also performs well when completely immersed in water. So unless your applications are on a sea wall or half immersed in water, salt spray test results do not apply.
A. This is a tough question to answer. It depends on your application and if the finish is properly maintained. Well maintained galvanized coatings can protect steel in most cases more than 60 years and in some cases more than 100 years.
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