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7
General Maintenance
To Clean the EI HES
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7000/7010 Series TQ GC/MS Operating Manual
3
If the contamination is serious, such as an oil backflow into the analyzer,
seriously consider replacing the contaminated parts.
4
Abrasively clean the surfaces that contact the sample or ion beam.
Use an abrasive slurry of alumina powder and reagent-grade methanol on a
cotton swab. Use enough force to remove all discolorations. Polishing the
parts is not necessary; small scratches will not harm performance. Also,
abrasively clean the discolorations where electrons from the filaments
enter the source body.
CAUTION
If insulators are dirty, clean them with a cotton swab dampened with
reagent-grade methanol. If that does not clean the insulators, replace them. Do
not abrasively or ultrasonically clean the insulators.
Figure 54.
EI HES parts to be cleaned
Source body
Repeller
Entrance
lens (1)
Ion focus
lens (2)
Post extractor
lens 2 (3)
Post extractor
lens 1 (4)
Extractor
lens (5)
CAUTION
The filaments, source heater assembly, insulators, source mounting plate, and
filament block cannot be cleaned ultrasonically. Replace these components if
major contamination occurs.
CAUTION
Do not use the abrasive slurry on the source mount bushings.