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Lifetime of galvanized layer on pipe against hot water flowing inside?

September 3, 2009

Dear Author,

I am a galvanizing engineer. One of our customer prospects came to me with pipe material to be galvanized. Before they send the material, they want me to answer their question first. They explain that the pipe will be used for circulation of water cooling (just common industrial water), the water temperature will be around 80-150 °C. How long (how many years) the life time of galvanizing layer in the inside of pipe will be? or in the other words, how fast the speed of corrosion per year with the mentioned situation?
Please advise me, which one is has longer durability between parkerizing and galvanizing? Your answer will be very valuable for me. Thank you very much for your support.
Best Regards,

Taufiq Abdoellah
galvanizing plant engineer - Jakarta, Indonesia

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First of two simultaneous responses --

The lifespan will depend on particulate matter, speed and turbulence or the water, pH, chlorides and sulfides in the water. The plate will last about 4 times longer at the low temp than the high temp.

James Watts
- Navarre, Florida
September 4, 2009

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Second of two simultaneous responses --

What thickness of zinc will you put on the inside of the pipe?

This will determine the life expectancy.

Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK

September 7, 2009