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5. OPERATING SUGGESTIONS
The liquid to be atomized flows through the entire converter, via a barbed port on the back of
the converter, and then the connected probe. It is recommended that plastic tubing chemically
compatible with the liquid to be atomized be used to connect the liquid delivery system to the
converter. Because soft tubing can easily expand and contract, making it difficult to accurately
control the flow of the liquid in critical applications, tubing elasticity should be given
consideration in intermittent applications where the flow will be rapidly interrupted. When the
atomized volume is critical, it can be beneficial to reverse the pump flow to prevent any
overspray.
Delivery systems such as valve-less metering pumps, syringe pumps or gear pumps are best
suited for atomization because their dispensation is steady and uniform. Valve-less metering
pumps and syringe pumps are recommended for critical applications. Peristaltic and piston
pumps produce a pulsating flow which is detrimental for many atomizing applications. They can
however give satisfactory performance when used in conjunction with pulse dampening devices.
Gravity feed systems could be considered for non-critical applications. Pressure reducing
regulators should be used when working with high pressure delivery systems.
Optimum atomization can only be obtained by empirically adjusting the amplitude and flow rate.
Typically the greater the flow rate, the greater the amplitude required. However, consideration
should be given not to set the amplitude too high in order to prevent uneven atomization and
probe cavitation. With very small volumes, a point is reached where the flow rate is so low that
inconsistent erratic atomization will take place.
Always energize the ultrasonics before starting the flow of liquid, and always terminate the liquid
flow prior to de-energizing the ultrasonics. Keeping the probe energized for more than 10
seconds without liquid flowing through it will cause the probe to overheat, adversely affecting
the atomizing process. When it is necessary to atomize a liquid intermittently, it is best to keep
the ultrasonics on, and cycle on and off the liquid flow to the probe.
Because the droplets typically drift downward at low velocity under the influence of gravity, the
probe should be mounted with tip facing downward, and air disturbances kept to a minimum.
Do not operate the probe when the ambient temperature or temperature of the liquid exceeds
140°F (60° C).
