Smetco Inc
Smetco S-Fusion Electrostatic spray booth for mold control. (Concept drawing)

Smetco's S-Fusion Electrostatic Pallet Sprayer featuring ESS Electrostatic spray nozzles.

Smetco's S-Fusion Spray Systems featuring ESS Electrostactic Spray Nozzles and X-Mold anti-mold treatment:

While Smetco has built its name in pallet handling and recycling we have expanded our product line to meet the growing need to fight mold on pallets and cut wood stock. Working closely with ESS and X-Mold we have developed an Electrostatic Spray system that effectively applies anti-mold treatment that leaves pallets and cut stock nearly dry as it exits the spray booth while maintaining effective anti-mold treatment coverage.

Some of the many benefits are:

  • Mold free pallets and cut stock.
  • Fewer customer rejections due to mold related issues.
  • Reduced chemical usage.
  • Greatly reduced drying time as compared to a typical dip method.
  • Better coverage than standard spraying methods.

Smetco S-Fusion Spray Systems can be customized to fit any application need, Inline, stand alone, with automatic feed and automatic stacking. Systems can be built for specific pallet size or a range of sizes, short boards to long boards, plywood and many other materials. We are dedicated to providing solutions to your material handling needs.

What is "air-assisted electrostatic spraying?"

Air-assisted electrostatic sprayers produce electrically charged spray droplets which are carried to the target in an air stream. Electrical charges on the surface of the spray particles cause them to be attracted to the target where they are directed. Coulomb's Law says that opposites attract, or more specifically, unlike electrical charges attract to each other. Because of Coulombic forces when charged spray particles are near any object they will be attracted to that object. They will follow electric field lines and wrap around and coat all sides.

ESS takes advantage of this physical principle to allow spray applicators to do a better job and to lessen the environmental impact by allowing smaller amounts of less toxic chemicals to be used. In addition ESS uses air-assistance to help with spray delivery. Air is necessary in electrostatic spraying to cause the charged spray to push deep into complex targets, such as pallets.

The force of electrostatic attraction is strong if the droplets are small and the droplet charge is sufficiently high. ESS sprayers produce highly charged spray droplets using a unique "embedded" induction electrode design. The result is the droplets have a force of attraction of 75 times that of gravity. This means droplets will reverse direction and move upwards, against gravity, to coat hidden surfaces.

Electrostatics, with air-assist, plus the right droplet size is a good combination for the best spray job. In the photograph to the right electrostatically charged spray is shown coating a plant leaf. Spray droplets move along electric field lines (Coulombic Forces again) and reverse direction to coat the underside of the target. Droplet size is important. If droplets are too heavy (over 60 microns) then no matter how highly they are charged they won't reverse their direction against gravity. MaxCharge droplets are 30 to 40 microns in diameter and charging levels are normally 6 mC/liter. This size droplet with this high charge results in attraction forces over 75 times that of gravity.

The heart of the Smetco S-Fusion Spray System is the Max-Charge induction electrostatic nozzle from ESS.

The original induction charging air-assisted nozzle was invented by Dr. Ed Law at the University of Georgia. ESS has made many improvements to Dr. Law's original concept and the result is a simple, safe, and reliable electrostatic spray nozzle system. This novel induction charging method has been found to be the best way to charge spray in dirty and dusty environments.

Induction charging can produce a very high charge without using high voltages. Other types of charging methods, such as contact charging, use voltages that are much too high to be safe or reliable in dirty environments.

Air and liquid enter separately at the rear of the nozzle. The air moves at near-sonic speed through the nozzle and impacts the liquid at the tip.


This causes the formation of optimum size spray droplets of 30 to 40 microns in diameter. The air pressure needed is only 12 to 15 psi. At these low pressures the nozzles last a long time.


As the spray is atomized the liquid passes an electrode inside of the nozzle. Electrons are induced onto the liquid stream and the droplets leave the nozzle with a high negative charge.


The droplets are carried in an air stream towards the target. The closer the charged droplets get to the target, the stronger the electrostatic forces of attraction.


Charged droplets can travel long distances without losing their charge. The droplets follow electrical field lines of force and wrap around the target. Once droplets hit the target they immediately lose the electrical charge.


The MaxCharge™ nozzle design allows the use of many types of spray mixes, including heavy powders mixed in all types of liquids, and the nozzle is easy to disassemble for cleaning.

"It's that simple"

For protection from mold, a Smetco S-Fusion Spray System using ESS electrostatic nozzles can deliver a consistent coating of X-Mold anti-mold chemical and get the chemical into tiny cracks, crevasses, and hidden surfaces that would otherwise be missed. A Smetco S-Fusion Spray System will prove its worth by minimizing your mold problems and reducing the number of customer rejects while reducing overall costs.

The picture to the left demonstrates how electrostatic spraying out performs conventional spraying techniques.

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