Galvanizing Process

Hot Dip Galvanizing is widely regarded as one of the most effective methods of corrosion protection for steel and the most popular protective process for all external steelwork. The principle reason for this is a combination of cost effectiveness and the extended life expectancy provided by effective corrosion control.
Hot Dip Galvanizing is unique, tough, long lasting, self-healing and covers internal and external surfaces.

Hot Dip Galvanizing provides a barrier between all internal and external steel surfaces and their environment. The steel is given maximum protection through the formation of continuous, tough, alloy layers that result in a metallurgically bonded coating.
We have recently completed work on our state of the art Galvanizing Plant, and to this we have added the largest pot in the country.

Bath Size : 12m long x 2.0m wide x 3.2m deep
Double Dip : 22m long x 1.93m wide x 0.5m deep by appointment
Maximum Lift : 6.4 tonnes

The hot dip galvanizing process consists of 3 distinct phases

Pre-Treatment
Galvanizing
Inspection

Pre-Treatment

Pre Treatment for galvanizing consists of 4 separate stages

Inspection - Items are inspected to ensure they are safe & suitable to galvanize. This involves checking whether they are adequately vented. Surfaces are checked for signs of contamination with paint, grease, etc. as these will not be removed in the process and would cause the process to fail.
Pickling - Acid strips the steel surface back to clean base steel.
Fluxing - A flux solution is applied to the steel to assist with the galvanizing reaction.

Galvanizing

Material is immersed in molten zinc at a temperature of around 450 degrees until the temperature of the work is the same as the Zinc. During this process the molten zinc reacts with the surface of the steel to form a series of zinc/iron alloys. These alloy layers protect steel from corrosion for 30-40 years and more.
As work is removed from the zinc, the zinc on its surface will begin to solidify, as this happens excess zinc is removed to ensure a smooth finish.

Inspection

The galvanized steel is first visually inspected for its appearance and conformity to standard. Batches may then be non-destructively tested for coating thickness and uniformity.