Process

Galvanizing is the practice of immersing oxide free iron or steel into molten zinc in order to form a zinc coating that metalurgically bonded to the iron or steel's surface.

The zinc coating protects the surface against corrosion by providing protection to the steel in two ways:

• It shields the base metal from the atmosphere
• Because it is more electronegative than iron or steel, the zinc gives cathodic or sacrifical protection

Even if the surface becomes scratched and the base metal is exposed the zinc is slowly consumed while the iron or steel remains protected from corrosion. The hot dip galvanizing process is adaptable to coating nearly all types of products such as tanks, sheets, strip, pipes and tubes, fittings, hardware, wire cloth, hollow ware, and structural assemblies.

All galvanizing consists of four fundamental steps:

• Surface Preparation
• Prefluxing
• Galvanizing
• Finishing

Preparation steps consist of cleaning and pickling operations that free the surface of dirt, grease, rust, and scale.

The pre-flux step serves to dissolve any oxide that may have formed on the iron or steel surface after pickling and prevents further rust from forming.

Clean, oxide free work is galvanized by immersion into molten zinc.