The line proportioner can be designed for use in portable
applications or installed in fixed piping systems.
For
portable applications the proportioner is equipped
with
hose connections to allow installation in a hose line.
Foam
concentrate is normally supplied from 5-gallon
pails
through a pickup tube. As noted above these
proportioners
are sensitive to the back pressure. Therefore,
care must be used in matching the discharge nozzle
to
the proportioner as well as the amount of hose between
the line proportioner and the nozzle. Line
proportioners
can be equipped with a metering valve to
allow
the desired percentage to be field set.