Chapter 4 49
Installation
Installing the GC Column With the Column Positioning Tool
Following are instructions for installing the GC column into the Model 5380 PFPD
using the new PFPD column positioning tool (Part #318949). This tool simplifies
column installation and minimizes the possibility of creating performance prob-
lems during column installation. The column positioning tool allows the column to
be properly installed without removing the detector body.
The column must be reinstalled whenever the combustor support is changed or if
peak tailing, poor peak shape, or poor reproducibility are observed. To minimize
degradation of the column tip, do not operate the detector at temperatures that
exceed the recommended maximum temperature of the capillary column. For good
chromatographic performance by the PFPD, the end of the capillary column must
be square and extend 0.5 mm to 1.0 mm beyond the upper end of the combustor
support.
1. Refer to the appropriate GC injection manual for general instructions on how
to install a capillary column into the injector port.
2. Slide the GC column nut (Part #223057) onto the end of the capillary column.
Slide a Q/qy" ferrule that matches the outer diameter of the column onto the
end of the column, with the tapered end facing into the GC column nut (see
Figure 4.13).
3. With the ferrule and nut on the column, insert the column end into the detec-
tor base. Gently push the column up well beyond the top of the detector body
in order for the column to be cut outside of the detector body. Loosely fasten
the column nut into the end of the detector base. Tighten the column nut just
enough to have the ferrule gently gripping the column while still allowing
column movement.
4. Trim the top of the capillary column using a column scribe, and use a magni-
fying glass to verify that a square cut has been achieved. Ensure that no
column or scribe debris falls into the end of the column or the detector body.
5. Wipe the column with a clean, methanol-moistened, lint-free lab tissue.
6. Carefully pull the capillary column about 16–19 mm (0.625"–0.75") down
into the detector body. The column needs to be below the top of the combus-
tor support before inserting the column positioning tool.
7. Wipe the PFPD column positioning tool with a clean, methanol-moistened,
lint-free lab tissue.
Caution: The column positioning tool must be clean before inserting it into the
detector body. Any dirt or debris on the column positioning tool will
cause problems with PFPD performance.
8. Using a lab tissue, gently insert the column positioning tool into the detector
body (see Figure 4.15). The column positioning tool must rest on top of the
combustor support.
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