Figure 5-18.--Vent fog precipitator.
The oil mist is caused when the oil gets warm in the
electrode. As the charged droplets progress up the
gear case and the air space of the entire lubricating
collector tube, they are subjected to the electrostatic
system. The larger mist droplets will settle by gravity.
field created between the high-voltage electrode and the
The fine mist will continue to rise, borne on air currents.
grounded collector tube. Since their charge is of the
same polarity as the high-voltage tube, the force of the
The vent fog precipitator employs the basic
electrostatic field forces them to the wall of the collector
phenomenon of electrostatic precipitation. The fine oil
tube, which is of opposite polarity. Here the oil is
mist borne on air currents vented in confined areas of
collected and flows back to the machinery reservoir.
machinery will rise and enter the bottom end of the
The oil-free air continues up and is vented to the
collector tube through the flame arrester assembly. The
atmosphere.
droplets are instantly charged by a heavy ion
concentration emanating from the ionizer electrode
The vent fog precipitator operates on 120-volt ac,
mounted on the end of the high-voltage repelling
60-hertz, single-phase power. The power pack is used
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