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NEWS & PICS

Grey Galvanized Steel – The “Grey Bar Effect”

Why does my galvanizing look Dull grey?

This out come is what we refer to as a ‘grey bar’ where the steel chemistry influences the metallurgic reaction that is galvanizing. The levels of phosphorous or silicon plus other elements in the steel can increase the iron content on the “eta” (top) layer resulting in a dull finish. This in no way is inferior or affects the performance of the coating, it just looks different as the photo’s depict. The spliced piece clearly shows the difference in steel chemistry reaction as obviously this member was immersed for the same time in each of the process tanks. This can be critical in architectual applications where asthetic’s are considered. Note while the ‘grey bar’ effect is dull it does accelerate the reaction resulting in almost double coating thickness.

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Paint Over Galvanizing Success Story

Contrary to perception. If applied correctly, as per the recommendations by the Galvanizers Association of Australia, paint co-exists adequately over galvanized steel. As exhibited at the Townsville Railway Station. Even the stainless steel used in construction has started to corrode.

If you are a designer and you want to design using the aesthetics of paint over galvanized steel here is a great example of it looking great and standing the test of time.

Click on the link above for more info on Paint over galvanizing

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Paint “Fails” – Woolworths Carpark – Mission Beach

These photos were taken only 4 years after this was built. The car park shade structure is already showing signs of huge amounts of corrosion. This not only looks unsightly, but it will eventually jeopardise the structural integrity of the shade structure. In the same car park, the bollards which were galvanized show no signs of compromise to its protective coating. Because the shade sail foundations are cast into the concrete it will present major issues in dealing with rectification.[nggallery id=1]

Paint “Fail” – Townsville Central

These photos are taken only 2 years after?construction?was completed. As you can see there is visible rust stains,?and compromised structural integrity.?Remedial works will be required to ensure the safety and aesthetics of the?building?albeit at significant cost.

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APG Galvanize Lavarack Barracks TSV

The Galvanizers Association of Australia have put together this excellent Case Study for the galvanizing of the steel structures for the Lavarack Barracks Townsville Army Base stage 4 of the development. We provided the protective surface coating for the structural steel components.

Click on this link to read the full case study