Powder
coating continues to gain in popularity as a versatile coating
with many uses. Among its advantages are environmental friendliness,
ease of color change and low material waste when powder is reclaimed
and reused.
Powder Line with Conveyor System
Finely ground powder paint can be applied by a number of different
methods. Most often, it is sprayed from manual or automatic guns
onto parts that have been electrostatically grounded. The powder
particles themselves are given a charge that allows them to be attracted
to the parts. This electrostatic method greatly decreases overspray
and waste.
One specialty application is the fluidized bed method, where parts
are heated and then dipped into an aerated tank filled with powder.
The hot parts retain a heavy coating which is then oven cured. Also,
very large objects may be coated on site through a flame spray process.
Powder is melted by the gun as it is applied, depositing a very
heavy coating on pipelines, water towers and the like.
Electrostatic powder systems require
pre-application pretreatment equipment to clean, protect and thoroughly
rinse the parts. Two ovens are required: one to dry the parts prior
to application and another to melt and cure the powder afterwards.
Coating is done with manual or automatic guns in a special booth
with the ability to reclaim and reuse excess powder. The booth itself
is located inside an environmental room, which controls temperature
and humidity for best results. High capacity powder coating systems
link all these processes together by conveyor.
Drawbacks: Application can be difficult to control with certain
shapes