| |
Powder coating is a method by which electrically charged powder
coating material is spray-applied to a grounded work piece.
Electrostatic attraction holds the powder to the part to be
coated until heat is added to flow the powder together and cure
it.
Since powder may adhere to the part for several hours, heat
curing can be done at the user's convenience. Should the uncured
powder coat become damaged or blemished during handling, the
powder can be simply blown off with air or vacuumed, and a new
coat applied.
System Components
An electrostatic powder coating system is comprised of a powder
feeder, power unit or electrostatic voltage generator, electrostatic
spray gun(s), and a powder recovery system.
Feed center
In the feed unit, powder is diffused by compressed air into
a fluid-like state. It is then siphoned out by the movement
of high velocity air flowing through a venturi and propelled
through powder feed tubing to the spray gun.
The feeder provides a controlled flow of powder to the spray
guns. Since powder and air volume are independently controlled,
dilution ratios can be adjusted to obtain the desired thickness
coverage needed to meet specific production requirements. The
feeder can provide sufficient discharge pressure and velocity
to feed a gun as remote as 50 feet away.
Power unit
A high-voltage, low-amperage power unit supplies an electrode
at the front of the gun. As the powder leaves the gun, the electrode
emits a field charge that is imparted to the coating material
as it is propelled toward the part. Once charged, the powder
particles are drawn and attach themselves to the grounded work
piece.
The power unit has sufficient voltage to assure maximum wraparound.
Voltage is operator adjustable up to 100 kV to minimize Faraday
Cage effect when spraying into corners and deep recesses, and
to ensure excellent wraparound and surface coverage on all surfaces
being sprayed.
Spray guns
Electrostatic powder guns are designed to shape the spray pattern
and impart an electrostatic charge to the powder. The spray
pattern is easily configured to accommodate the type of coating
used and the shape of the part being coated.
Please contact us for
more information.
All information in this website are from http://www.nordson.com,
which is our parent website.
Top
|
|
|
|
