GE MOA 280i, Руководство по эксплуатации и обслуживанию

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GE Analytical Instruments ©2006
13-13
DLM 14291 Rev. A
drawn into the bubbler, bringing the pressure in the bubbler back to
atmospheric pressure.
•
When the union is removed and the bubbler is at atmospheric pressure,
disconnect the IFD line from the NOA frit restrictor.
Septum Replacement
After 50-100 injections, the septum on the purge vessel will need to be
replaced. The best procedure is to replace the septum on a regular basis after
a fixed number of injections. The number of injections will depend on the
gauge of the needle used, and whether the needle is bent or distorted. Large
gauge needles or needles with bent tips will core the septum and require more
frequent replacement than small gauge needles with sharp tips. To some
extent the ease of insertion can be used to tell when it is time to replace the
septum. With a new septum, some force is required to insert the needle, but
after many punctures, the septum loses its integrity and the needle can be
inserted without force. To replace the septum, follow the procedures to open
the purge vessel, then remove the old septum from the screw cap and discard.
Install the new septum with the Teflon side facing the reducing agent. The
lifetime of the septum can be extended by varying the location on the septum
when injecting.
Cleaning the Purge Vessel
After running samples, follow the procedure below to clean the purge vessel.
By following this procedure each time the purge vessel is used, clogging of the
glass frit in the purge vessel will be prevented. For nitrates, turn off the
circulating water bath and allow the glassware to cool before cleaning the
purge vessel. To clean the purge vessel:
•
Follow the procedures above to drain the reducing agent from the purge
vessel.