| PowderCoil™ Technologies
PowderCoilTM technology is an advanced, highly
automated, yet simple method of high speed powder coating a continuously
moving strip of steel. It utilizes the latest in application
and curing technology to produce one of the best coil to coil
pre-painted steels available.
Patented Powder Paint Technologies
Powder Jet: This patented powder
application technology was specifically developed to replace
continuous coil, spray gun technology.
The Powder Jet has no moving parts, pneumatically applying
powder paint directly to the moving metallic strip. The system
precisely controls the volume and width of the powder emission
to match the speed and size of the metallic strip. The metallic
strip is coated on one or both sides while the film thickness
is precisely controlled to customer specifications. The Powder
Jet utilizes focused line-source electrostatic charging technology
which results in particulate ionization many times greater
than gun systems. The applicator produces a 90% deposition
factor that enables the PowderCoil™ system to meet cost
and quality parameters comparable to any liquid coil coating
operation.
AdPhos NIR® Oven Curing Technology:
NIR® ovens
are the most technologically advanced powder coat curing systems
available today. The technology produces a focused,
high energy density field, that penetrates the coating and reacts
with the powder chemistry resulting in lighting fast melt-flow & curing
cycles. As NIR® radiation passes through the coating, it
reflects off the surface of the metallic substrate and thoroughly
cures the powder paint system. This principal allows for high
speed processing of difficult colors like yellow and white. Each
system is designed to precisely calibrate functionality in coordination
with line speed, strip width, powder chemistry and film thickness.
NIR® technology enables the PowderCoil™ system to operate
at high speeds while producing a fully cured, durable, and long
lasting paint system.

DuPont® Performance Powder Coatings (Ray-Tec®):
DuPont® Powder
Coating’s manufacture the Ray-Tec® brand
of high performance, fast curing, powder paint systems, specifically
designed for the PowderCoil™ technology. Ray-Tec® powders
are engineered to react with NIR® radiation resulting in
extremely fast and thorough cross-linking of thermoset powder
chemistries. Each formulation is blended to exacting customer
specifications for color, texture, visual characteristics and
performance requirements. Ray-Tec® powders are available
in a broad range of epoxy, polyester, hybrid and urethane formulations.
PowderCoil™ is Unique
PowderCoil™ is unique, compared to contemporary “gun” application
technology. Gun technology pneumatically conveys powder through
tubing into the gun which sprays the part. The powder flow is
dispersed and uncontained such that the ratio of applied powder
to unused powder can be as low as 60/40.
PowderCoil™,
on the other hand, utilizes a nozzle arrangement to
apply
powder to the strip. The special powder nozzle directs the powder
flow to the strip and controls the volume and velocity
of the powder. The width of the
nozzle is adjusted to the width of steel strip.
The transmission of charged powder particles occurs
in a focused single direction, through a precision sized horizontal
opening. A fluidized bed environment is created within the ejector
providing for uniform particulate distribution. Powder is pneumatically
driven through the electrostatic zone and exits the ejector developing
a wedge shaped spray pattern.
The width of the powder stream is easily controlled by varying
the width of the opening. The spray pattern and volume of powder
is consistent resulting in no coating overlap. The volume and velocity of the powder is governed
through the pneumatic pressure controls. Given pre-designed film
thickness the application rate is increased or decreased in correlation
with line speed. The PLC controls the entire process, removing
operator variance and inconsistent film builds.
What is Powder Coating?
Contemporary powder coating is an advanced method
of electrostatically applying a decorative and protective finish
to a wide range of materials and products used in industry and
by consumers. Some
refer to powder coating as “dry
paint.” Powder
coatings are applied using pneumatic pumps and either manual
or automatic electrostatic powder spray “guns” that
give the powder an electrical charge. The substrate to be coated
is grounded, so the charged powder is strongly attracted to it.
Once sprayed (coated) the article is then heated (baked) in either
a gas, electric or infrared oven until the powder particles melt
and fuse into a durable, solid paint film. Baking (curing) times
are a function of the film thickness, paint specifications and
performance requirements.
The development of First Precision's PowderCoil™ significantly
improves the powder painting process. Our patented PowderJet technology
is capable of overcoming the air boundary barrier that is present on
the metal surface in high-speed metal processing lines (100 - 500 ft/min).
This allows for the integration of powder painting in coil to coil
operations, whereas previous powder gun technology was confined to
small parts and slow-speed lines.
Powder Paint vs Liquid Paint
It’s fundamentally important to recognize
the difference between powder paint and liquid paint. As powder
paint is applied, essentially 100% of the material being applied
is paint. Liquid paint, by contrast, is composed of pigments,
resins, antifoaming agents, and most importantly, solvents.
These solvents are called VOC’s (volatile
organic compounds), i.e., acetone, benzene, dichloromethane,
ethanol, methanol, and toluene. Solvents serve as carriers to
allow the paint to flow, homogenize and dry. It’s in the
drying process that solvents separate from the solids. The solvents
must be contained and controlled such that less than 1% can escape
to the atmosphere. Capture, control and containment of 99+% of
solvent vapors is a very costly and environmentally problematic
issue.
Federal, state, and local regulations severely
limit the volume of VOC’s released into the atmosphere
and all liquid paint applicators are monitored regularly. Non-compliance
can threaten the business. Powder coatings have NO VOC’s,
hence dry paint.
Thermoset and Thermoplastic Coatings
There are two basic powder paint chemistries; thermosets
and thermoplastics. The First Precision LLC/PowderCoil™ technology
is capable of applying both thermoset and thermoplastic coatings.
Thermoset Coatings
Thermosets are characterized by temperature or radiation
driven chemical reactions which fuse the paint system thus curing and
stabilizing the coating. Thermosets are composed of high molecular weight
solid resins and crosslinkers. Finished thermoset coatings do not soften
when reheated. Once cured (fused) the coating forms a polymer network
which is highly resistant to coating breakdown. Thermosets can be high
or low gloss, flexible or hardened.
Thermosets are used for decorative applications (color,
gloss, and appearance) and functional (mar resistance, weatherability,
corrosion). Most systems
call for a dry film thickness (DFT) of between 0.8 mils – 4 mils.
PowderCoil™ is capable of producing a light or heavy DFT product in
(1) pass through the line. Most liquid paint lines would require two
or three
passes to duplicate PowderCoil™ DFT.
Thermoplastic Coatings
Thermoplastic systems, such as nylon, melt and flow when heated, yet unlike
thermosets, soften when reheated. Thermoplastic powders do not chemically
react during application or baking. They are commonly used as functional
coatings and typically are applied thicker than thermosets. Common uses
of these coatings are electrical insulation components, high corrosion
environments, high wear applications and appliance parts (freezer baskets,
dishwasher racks, etc).
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