Powder coating is the process of coating a surface
in which a powder material is applied using an
electrostatic or compressed air method. The applied
powder is then heated (cured) to its melting point,
after which it flows to form a smooth film which
dries to a firm, durable finish very resistent to
scratches, cracking, peeling, UV rays and rust.
The entire
powder coating process involves several steps.
Very
generally:
a
blasting, stripping and/or solvent cleaning step to insure
the substrate is free of any oils, dirt, rust, mill scale,
etc; This is an additional charge
a
pretreatment step (an important step not done by all
coaters) during which the product is treated with a
pretreatment chemical or conversion coating, usually
phosphate or zinc based, to further protect it and improve
the surface for powder adherence;
rinse,
rinse, rinse..dry completely then
powder
coat, usually done with an electrostatic gun, but sometimes
in a fluidized bed;
finally,
FULLY cure the powder in the oven, generally at 375-400 deg.
F, 15-20 minutes (varies) , making sure the oven is
preheated to temp