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Maintenance Page
Note that if you want some comments from us concerning any
of the instrument maintenance that isn't on this page, then please feel free to
contact the
lab manager and ask.
I] EA
i) replacing quartz inserts
ii) replacing/repacking the
combustion tube
iii) replacing/repacking the
reduction tube
iv) repacking the Mg(ClO4)2
(magnesium perchlorate) water trap
v) cleaning the zero blank
autosampler
II] TC/EA
III] TIC/TOC
IV] GC/C-TC
V] GasBench
i)
VI] Mass Spec Maintenance
i) Oil Change
ii)
MAT 253 ion source
disassembly (this links to a power point presentation showing details
of disassembly)
I] EA Maintenance
i) replacing quartz inserts
| ii)
replacing/repacking the combustion tube
On September 26th, 2005 the Delta Plus and MAT 253 were shut down for an oil
change. As an extra safety, the main switch was turned off (which isn't
necessary or recommended in the future). As both the EA and TC/EA were
plugged into the Delta Plus, this meant that they were also shut off. The
rapid cooling of the combustion tube in the EA resulted in it cracking and
subsequently emptying the helium tank that is plumbed into it. This
unfortunate event was an
opportune moment to replace the combustion tube for the first time! We had
purchased an extra, prepacked combustion tube from Costech earlier so
the change was very easy. We now pack our own combustion tubes. The first picture on the right shows a new combustion tube with a
quartz insert in it. The second picture shows our used reduction tube after
an estimated 600 samples. Gas flow comes in through the bottom of the tube
where oxygen (as O2 or as NxOy) is trapped
in the form of CuO (black).
iii) replacing/repacking the
reduction tube
On the day that the combustion tube cracked, we
went ahead and replaced the reduction tube as well. Although the tube was in
perfect shape and could have been repacked, we chose to keep it for show and
tell and repacked a new tube with copper wire. |
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New, prepacked combustion tube with quartz
insert. Note that the prepacked tubes come with a piece of plastic tubing in
them that should be removed. |
Used reduction tube after an estimated
600 samples. Gas
flow comes in through the bottom where oxygen is trapped as CuO (the black
stuff). |
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iv) This is what your data will look like if you do not replace the
copper in the reduction reactor before it is depleted.
Note the peak occuring on the m/z 30 trace. This is NO (nitrous oxide) which
has obviously not been reduced in the reduction furnace. It's not a good thing
when all of the nitrogen has not been reduced to N2. If you see such
peaks in your data then your reduction reactor is probably spent. In general we
get about 1000 runs safely. After that we replace both the oxidation and
reduction reactors.
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Page last updated: April 16, 2007
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