The Galvanizing Process
Galvanizing is the practice of immersing clean, oxide-free iron or steel into molten zinc in order to form a zinc coating that is metallurgically bonded to the iron or steel's surface. The zinc coating protects the surface against corrosion by providing protection to the iron or steel in two ways.
1. It shields the base metal from the atmosphere
2. Because it is more electronegative than iron or steel, the zinc gives cathodic or sacrificial 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 fabricated and non-fabricated products such as wire, 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

The preparation steps consist of cleaning and pickling operations that free the surface of dirt, grease, rust and scale. The preflux 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. Finishing operations include quenching, removing excess zinc and inspection.

Benefits of Galvanizing
Complete covering of most complex steel product forms; even the most inaccessible spots are protected well with a zinc layer. Vital spots like angles and edges are protected far better than if they were sprayed or painted.

Lowest First Cost - Hot Dip Galvanizing is lower in first cost than many other commonly specified protective coatings for steel.

Less Maintenance/Lowest Long Term Cost - Even in cases where the initial cost of hot dip galvanizing is higher than alternative coatings, hot dip galvanizing is almost invariably more cost effective in the long term because it lasts longer and needs less maintenance.

Long Life - The life expectancy of hot dip galvanized coatings on typical structural members is far in excess of 50 years in most rural environments, and 20 to 25 years plus, even in severe urban and coastal exposure.

Reliability - Galvanizing at Metalplate is carried out to the appropriate ASTM Standards for hot dip galvanizing. Coating life and performance are reliable and predictable.

Toughest Coating - A hot dip galvanized coating has a unique metallurgical structure which gives outstanding resistance to mechanical damage in transport, erection, and service.

Automatic Protection For Damaged Areas - Hot Dip Galvanized coatings corrode preferentially to steel, providing cathodic or sacrificial protection to small areas of steel exposed through damage. Unlike organic coatings, small damaged areas need no touch up.

Complete Protection - Every part of a hot dip galvanized article is protected, even recesses, sharp corners and inaccessible areas. No coating applied to a structure or fabrication after completion can provide the same protection as hot dip galvanizing.

Ease of Inspection - Hot Dip Galvanized coatings are assessed readily by eye, and simple non-destructive thickness testing methods can be used. The hot dip galvanizing process is such that if coatings appear sound and continuous then they are sound and continuous.

Faster Erection Time - As hot dip galvanized steel members are received they are ready for use. No time is lost on-site in surface preparation, painting and inspection. When assembly of the structure is complete, it is immediately ready for use, or for the next construction stage.