MKS HPQ3, Руководство по оборудованию

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MKS Instruments UK Ltd
HPQ3 Hardware Manual – SP101019.101 October 2012
52
7.5 Ion Source cleaning
7.5.1 Cleaning while fitted to the analyser
Sometimes it is possible to clean the ion source without removing it from the analyser. For the user
who has the necessary equipment available including a means to suitably dry the analyser, it is
usually worth trying this method before removing or replacing the ion source.
However, it is likely only to be successful where the source is contaminated with loose or alcohol
soluble deposits.
Insert the analyser into the measuring cylinder so that the knife edge side of the flange rests on the
lip of the cylinder. Note the level which the ion source comes to on the measuring cylinder before
removing the analyser and filling the measuring cylinder with sufficient iso-propyl-alcohol to cover
the ion source only.
Note: the measuring cylinder should be of a diameter and length to accommodate the analyser.
Put the measuring cylinder into the ultra-sonic bath for 10 to 15 minutes.
Remove the analyser and allow any excess alcohol to drain off. Keep the analyser inverted
(feedthrough upper most) until it is dry.
Do not let any alcohol run down the analyser into the flange assembly as this may lead to
problems.
Check the condition of the ion source. A second or third wash may be required.
The ultra-sonic bath may loosen some of the screws in the ion source. Take care not to throw
these away when discarding the alcohol.
The analyser must be dried of cleaning solution before it can be used. We recommend the use of a
clean oven for this purpose. The oven should be set at 80
0
C and the analyser baked for at least
two hours.
Check the documentation on your cleaning solution for guidelines on handling the substance and
any fire or explosion risks involved.
After the bake period, check all the screws in the ion source are tight and re-fit the analyser to the
vacuum chamber.
A further bake under vacuum will be required to drive off any remaining residue.