FEI Quanta FEG 250, Руководство пользователя, Страница: 200 / 228

System Options: CryoCleanerEC
9-52
FIGURE 9-45 PLASTIC CAP FILLING POSITION
PLASTIC CAP OPERATION POSITION
Removing Nitrogen Vessel
WA R N I N G !
Use the Safety pliers provided when handling the Nitrogen
vessel.
Removing the Nitrogen vessel depends on the level of contamination
found in the specimen chamber. If the level is unusually high then the
CryoCleaner could work continuously till improvement is seen,
otherwise normally after approximately 2 to 3 hours the Nitrogen
vessel can be removed.
Note:
It is not recommended to leave it inside the vacuum vessel after all
nitrogen evaporates, because contamination evaporates back to the
chamber.
1. Vent the specimen chamber (the excess LN2 starts to boil).
2. Unclip the Nitrogen vessel from the Vacuum vessel. Lift the
Nitrogen vessel out of the Vacuum vessel by the Safety pliers
placed under the ring on the neck of the Dewar cylinder.
3. Place the Lid over the Vacuum vessel to seal it from the
atmosphere (fix the clips). Pump the specimen chamber again,
however the microscope vacuum remains cleaner than before and
sample contamination is still reduced.
4. Remove the cap from the Nitrogen vessel and pour out the excess
LN2 into a suitable container.