Technical Description: Inlet
Rapid Multi-Stream Sampler
Thermo Fisher Scientific
Prima PRO & Sentinel PRO Mass Spectrometers User Guide
C-21
To reassemble the flow sensor, first locate the o-rings in the recess in
the sample tube body. Then refit the bracket but leave the screws
quite loose at this point. Fit the flow sensor PCB assembly to the
bracket. Tighten down the PCB retaining screws and finally the
bracket retaining screws (via the holes in the PCB). This procedure
ensures the o-rings are correctly centred on the pressure transducer
tubes.
To refit the sample tube into the RMS, first remove the sample arm
so that the various seals can be assembled on to the end of the sample
tube without damage. Otherwise, reassembly is the reverse of
disassembly
The gas inlet fittings are screwed into the main body. The thread type
is 1/8" BSPP (alternatively G1/8, or ISO 228/1). This is a parallel
thread, so a gasket type seal is used between the fitting and the RMS
body, and not formed on the thread itself.
Caution!
Alternative threads such as 1/8” NPT or 1/8” BSPT are
similar but not identical. Damage WILL result if these are used.
A fitting may need to be removed in the event of damage to the
compression faces of the fitting, or in the event of contamination (a
pocket of contaminants may reside behind the fitting even after
flushing through).
Unscrew the fitting and replace / clean as required. The seal is
generally reusable but replace if in doubt.
The above procedures will have exposed all areas that can be wetted
by sample gas, and no further disassembly is required for complete
cleaning.
The RMS stator should be cleaned in situ.
Particulate contamination should be removed initially by blowing
with a clean inert gas, such as nitrogen. More stubborn
contamination can be removed by wiping with a tissue moistened
with clean isopropanol (specifically, free from non-volatile
impurities) or another suitable solvent. Difficult to access regions
may require cleaning in an ultrasonic bath. The ports in the main
body should be flushed through, working from the top downwards.
Solvents in pressurised (aerosol) containers are convenient for this
providing they meet the above requirements.
Do not use excessive solvent for cleaning elastomeric seals as it can
cause the seal to harden and subsequently fail or leak. All metallic
parts can be cleaned with solvents.
Inlet Ports
Cleaning
Procedure
