Teledyne 3700, Installation And Operation Manual

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3700 Portable Samplers
Section 2 Setup Procedures
2-4
Once the coupler is attached to the pump tube, removal is dif-
ficult, and may require cutting the tube.
2.4.2 Attaching PTFE
Suction Line
Attach the PTFE line to the pump tubing by inserting the line
into the pump tubing and securing it with a suitable clamp.
2.4.3 Routing of the Suction
Line
Route the line from sampler to sampling point so that it is contin-
uously sloped downhill. This helps to drain the suction line when
the peristaltic pump reverses to purge the line, and minimizes
the possibility of cross contamination. When the sampler is used
in near freezing temperatures, drain the suction line thoroughly
to minimize the possibility of frozen liquid clogging the line.
2.5 Strainers
The
3
/
8
inch ID vinyl suction lines are shipped from the factory
with our standard weighted polypropylene strainer (Figure 2-2)
installed on one end of the suction line and a tubing coupling on
the other end.
Additionally, Teledyne Isco offers two low flow stainless steel
strainers (Figure 2-3) for
1
/
4
inch ID and
3
/
8
inch ID suction lines.
For sampling from highly acidic flow streams, a weighted, CPVC
plastic-coated strainer is available (Figure 2-4).
The use of the strainer is optional. When heavy suspended solids
are involved and flow stream velocities are significant, some field
investigation results indicate that more representative samples
are obtained without the strainer.
You can purchase bulk suction line without strainers. Refer to
the
Accessories List in the back of this manual. The strainer pre-
vents solid particles larger than a specific diameter from
entering and clogging the suction line. Teledyne Isco recom-
mends its use for bottom sampling or sampling from streams con-
taining large solids. The
1
/
4
-inch strainers supplied for use with
the
1
/
4
-inch ID suction line have
15
/
64
-inch (0.56 cm) diameter
holes. The
3
/
8
-inch strainers supplied for use with the vinyl or
PTFE
3
/
8
-inch ID suction line have
23
/
64
-inch (0.9 cm) diameter
holes.
Figure 2-2 Standard Weighted Polypropylene Strainer