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Benefits
Galvanized steel can last for many decades if other supplementary measures are maintained, such as
paint coatings and additional sacrificial anodes. Corrosion in non-salty environments is caused mainly
by levels of sulfur dioxide in the air.

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Fig. 6. 14 Galvanizing scheme

Applications
The most common use for galvanized metal is construction steel, also known as mild steel. Every year
thousands of tons of steel products are getting coated with a thin layer of zinc. In developed countries
most larger cities have several galvanizing factories, and many items of steel manufacture are
galvanized for protection. Typically, these include: street furniture, building frameworks, balconies,
verandahs, staircases, ladders, walkways, and more. Hot dip galvanized steel is also used for making
steel frames as a basic construction material for steel frame buildings. 30
In the early 20th century, galvanized piping replaced previously-used cast iron and lead in cold-water
plumbing. Typically, galvanized piping rusts from the inside out, building up layers of plaque on the
inside of the piping, causing both water pressure problems and eventual pipe failure. These plaques
can flake off, leading to visible impurities in water and a slight metallic taste. The life expectancy of
galvanized piping is about 40–50 years, but it may vary on how well the pipes were built and installed.
Pipe longevity also depends on the thickness of zinc in the original galvanizing, which ranges on a scale
from G01 to G360 (Fig. 6. 15). 31

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