Protecting steel is an essential factor in the economic utilization of steel in all applications. Every year rust and corrosion cause damage in steel and result in loss of several billion Riyals in buildings, plants, equipment, tools all over the Kingdom of Saudi Arabia.

Through the years companies used many corrosion prevention systems to protect its steel, like coating with epoxy or other type of protective paints. These systems can only provide a limited protection over a limited period of time. With time, coating will be compromised, from that point of time corrosion will begin spreading again beneath the protective coating film. Restoring the protection will require repeated treatments every time, resulting in higher risk of steel strength compromised and compounding costs over time for repeated inspection and treatment.

Hot dip galvanizing protects the steel surface against corrosion in two ways; it shield the base metal from atmosphere because it is more electronegative than iron, also the protective zinc layer will seal the steel surface metallurgically from its environment. If the surface is damaged in any way the remaining zinc in surrounding galvanized area will maintain the protection by the cathodic (or sacrificial action). This means galvanizing steel will provides the best quality, lowest risk and lowest long-term costs (in many cases also the lowest initial costs) compared to any other form of corrosion control and prevention

Hot dip galvanizing is also environmentally friendly since it will increase the expected life span of the steel products for many years (over 70 years), and since both steel and zinc are fully recyclable at the end of their service life without the loss of any of their chemical or physical properties.

Benefits of Utilizing Galvanized Steel

1. Durable Hot-dip galvanized steel delivers a maintenance-free corrosion protection for 75-100 years.
2. Economical (maintenance cost) Galvanizing requires no maintenance, the initial cost, of a bridge rail yard structure etc, is the final cost.
3. Sustainable and Recyclable Galvanizing steel lasts for many years, Zinc and steel are 100% recyclable without the loss of chemical or physical properties.
4. Safe since the galvanizing process applies zinc on difficult to reach corners as for the inside of poles, towers, and handrail; places where corrosion usually begins. Additionally; it lowers the risk of compromising steel quality because of its durability. Galvanized reinforcing steel in concrete bridge decks corrodes slowly and in such microscopic form it does not cause spelling of concrete like epoxy coating.

How we do it

Preparing the Steel items is most important to obtain best galvanizing quality. Items must first be clean (please refer to our website for more specific details on preparation of the fabricated items), so that it can be completely immersed in a series of pre-treatment baths to prepare the surface for galvanizing, and then be submerged in a bath of molten zinc at 450degree. Preparing also include making proper holes for hanging and proper draining the liquid zinc.

To insure high quality Hot Dip Galvanizing results, preparation should starts before delivering the steel items to galvanizing factory.
The hot dip galvanizing process consists of three distinct phases;

Pre Treatment for galvanizing consists of 4 separate stages

• Inspection – Items are inspected to ensure they are safe & suitable to galvanize. This involves checking for adequate venting, clean from welding slag and for any sign of steel surface contamination with paint, grease, etc. as these will not be removed in the pre-treatment process and would cause the process to fail.
• Degreasing – Steel is immersed in a degreasing solution which removes light oil contamination.
• Pickling – dipping in Acid tank will mill strips the steel surface to its original clean base steel.
• Fluxing – A flux solution is applied to the steel to clean from oxidization and 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 years to come.
• We add Aluminum with the zinc kettle to improve the anti corrosion properties of the coating and give a good finishing
• Steel is removed from the kettle then usually transferred to a quench tank where it is cooled to allow handling.

Post treatment

This will include the final inspection and final preparation

• Preparation includes clearing item from excess zinc and bundling in the finish product area.
• visual inspection; steel surface should be free from bare spots, blisters lumpiness, ash inclusion, white rust, general roughness
• coating thickness uniformity, this is usually tested using magnet thickness gage (non destructive test)
• Adhesion of the zinc to the steel surface. This is usually performed using Pivoted hammer.