Galvanized iron cannot be used for articles in which food is to be contained
as zinc forms poisonous compounds upon coming in contact with meat or vegetable
acids. It is therefore used for articles which need a strong, non-rusting material,
and which are not intended for use as food containers. Such are:
Water pails, Ash sifters, Dish drainers, Garbage pails, Ash cans, Refrigerator pans.
Manufacture of Galvanized Iron
Zinc-plated ware is manufactured by two processes.
In the dipping process the sheet iron articles are first cleansed of any rust
or dirt by immersing them in dilute sulphuric or hydrochloric acid. They are
then washed in cold water, scoured with sand, and plunged into the zinc bath.
If flat sheets are being coated they are passed through two iron rollers to
smooth them. The thicker the sheets, the longer will be the time required to
coat them, as it is necessary for the iron to attain the same temperature as
the zinc before it will adhere well.
The electric process, otherwise known as "cold galvanizing" is growing more
successful every year. It is far more satisfactory in coating sheets than in
coating articles of irregular shape, as the electric current does not deposit
the zinc evenly on such shapes. The advantage of the electrical process is that
the toughness of the iron is not impaired by heating, as in the dipping process,
and the coating adheres better.
Care of Galvanized Ware
Only hot water and soap should be used in cleaning galvanized ware, as it
is easily attacked by chemicals. Stains may be removed by rubbing with kerosene,
followed by a thorough rinsing with hot water.