ISCO 4230 - Teflon Line Connector; Attaching the Teflon Bubble Line; Attaching the Vinyl Bubble Line

4230 Flow Meter
Section 3 Installation
3-11
should recognize that a larger bubble line will result in increased
power consumption, a concern if you must power the flow meter
by battery. You should keep the bubble rate at one to two bubbles
per second, regardless of bubble line size.
3.5.4 Teflon Line Connector The Teflon bubble line attaches to the flow meter with the Bubble
Line fitting on the side of the case and the silicone rubber tubing
connector. The tubing connector is a short length of 0.109 inch
(0.20 cm) ID, 0.192 inch (0.49 cm) OD silicone tubing attached to
a barbed fitting on the case.
The
1
/8" OD bubble line simply slips inside the silicone tubing,
forming a reliable union you can make and unmake without
tools. This type of tubing connector is superior to a ferrule or
compression type tubing fitting for this application due to its
simplicity of use (no tools required), its lack of small parts you
can easily lose or misplace (ferrules and nuts), and its long term
reliability when used with the semi-rigid bubble line Teflon
tubing.
3.5.5 Attaching the Teflon
Bubble Line
To attach the Teflon bubble line, first slip the 2 inch (5.1 cm)
length of
1
/4" (0.63 cm) ID vinyl tube included in the instrument
accessory package over the end of the bubble line. Grasp the sil-
icone tube to stiffen it and insert the end of the bubble line into
the silicone tube.
Slip the short length of vinyl tube over the union and force in
onto the shoulder of the barbed fitting. The purpose of the short
length of vinyl tube is to support the union, preventing fatigue or
kinking of the silicone tube.
To remove the bubble line from the tubing connector, first pull
the vinyl tube off of the barbed fitting and slip it down the bubble
line. Grasp the end of the silicone tube and then pull the bubble
line straight out of the silicone tube.
Several replacement lengths of the silicone tubing are included
in the instrument accessory package. Install them on the unit by
simply forcing the end of the tube over the barbed tubing con-
nector.
Note
Avoid placing too much tension on the silicone tube where it
attaches to the barbed fitting. Try to direct the Teflon tube
straight away from the fitting rather than at a sharp angle. This
will reduce the likelihood that the tubing will tear and leak
around the fitting.
3.5.6 Attaching the Vinyl
Bubble Line
The vinyl bubble line attaches directly to the barbed fitting.
Remove the silicone tube and slip the
1
/8" (0.32 cm) tubing over
the fitting.