Difficulties in painting hot dip galvanized steel structures - Part 2

Hot dip Galvanising is not a very environmentally friendly process. The pretreatment includes acid picking that can potentially allow the ingress of hydrogen ions into the steel structures leading to hydrogen embrittlement also known as hydrogen induced / assisted cracking. The zinc bath also limits the size and shape of the structure to be galvanized. Other defects on the zinc layer such as flaking,, dross, pinholing can lead to surface imperfections. Zinc based coating techniques have greatly improved in recent times and the need to use environmentally and financially unfriendly galvanizing is replaced with activated zinc based coatings as primers. It is often combined with one or more layers of intermediate and top coats to form a long term corrosion resistant coating system as per ISO 12944 that can be maintained easily as well. Application of ambient temperature cured liquid paint saves time and money.