MKS Instruments UK Ltd
V2000-P Hardware Manual
– SP102006.103 March 2013
28
Mass spec maintenance
The only routine maintenance required by the quadrupole is to change the filaments. The filaments will wear out
in time and changing filaments is fully described in the Microvision 2 manual. Also, the ion source may need to
be cleaned which would be done as part of the filament replacement procedure, again this is fully described in
the Microvision 2 manual.
CAUTION
The quadrupole analyser is a delicate instrument which is
easily damaged and can be expensive to repair. The safest
place for the analyser is in its vacuum chamber, so leave the
analyser where it is until you have everything ready.
Removing the analyser
Before you can change the filaments or clean the ion source the quadrupole analyser must be removed from the
vacuum chamber. Before removing the analyser check that you have all the parts and tools ready for the
maintenance work. Also, have ready something to stand the analyser on, a small vice is useful for this.
The process valve fitted between the RGA chamber and the process chamber will allow the RGA chamber to be
vented to atmosphere without affecting the process chamber. We would recommend venting the RGA chamber
when the process chamber is not being run, just in case there is an unexpected accident.
To remove and replace the analyser you will need:
One pair of suitably sized spanners
One CF40 copper gasket
1.
Shut down the Vision 2000-P system.
2.
Make a note of the orientation of the analyser with respect to the vacuum chamber. This is most easily done
by making a mark on the vacuum chamber in line with the locking pip on the analyser’s feedthrough
housing.
3.
Remove the six M6 bolts.
4.
Carefully withdraw the analyser from the vacuum chamber. Leave the old copper gasket in place until you
are ready to fit the new one, it will help protect the knife edge from accidental damage.
Re-fitting the analyser
1.
Note the gas inlet tube on the top of the analyser source. Look into the vacuum chamber and note the
ceramic socket which the gas inlet tube must mate with when you re-fit the analyser.
2.
Clean, using a suitable solvent, and dry the new copper gasket then slip it over the analyser in place of the
old one.
3.
Carefully, insert the analyser into the vacuum chamber trying not to let the leads touch the wall of the
vacuum chamber. Make sure the gasket does not slip out of its slot as you push the flanges together. Make
sure that the gas inlet tube on the top of the analyser mates with the ceramic socket. When properly mated
the analyser flange should be flush with that of the vacuum chamber. If the two flanges are not parallel, the
gas inlet tube is not in the ceramic socket.
4.
Rotate the analyser flange so that it is in the correct orientation.
5.
Bolt the flanges together remembering to tighten opposite bolts equally.
6.
Re-fit the Microvision 2.
Detailed views and information on the analyser can be found in the Microvision2 user manual.
