Thermo Scientific Prima PRO, Руководство пользователя

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Technical Description: Inlet
Rapid Multi-Stream Sampler
Thermo Fisher Scientific Prima PRO & Sentinel PRO Mass Spectrometers User Guide C-17
sample tube / main shaft. Typically, one of the seals is retained in
the sample arm assembly and the other remains on the sample
tube / main shaft assembly. In some instances both seals may
remain on the sample tube / main shaft and can be left in place as
long as they are firmly seated.
Removal of the spring-loaded seal from the sample arm exposes
the
2 µm stainless steel mesh screen which acts as the filter. The
filter can be removed with a pointed tool but will be destroyed or
irreparably damaged in this process therefore ensure a spare is
available before removal. Care should be taken to avoid
damaging or scratching of the sample arm.
Press the new filter into place, a flat ended piece of 1/4” / 6 mm
diameter rod serves as a suitable tool, so that it is well seated in
the bottom of the hole. Replace the spring / seal assembly and
position the sample arm over the main body assembly in
approximately the correct orientation. Push into place. Ensure the
seal remains in place during this operation. Refit the four
retaining screws ensuring the head is correctly positioned over
the inlet port it was on when removed. Refit the sample return
seal and cover and finally, refit the stator cover.
General Inspection
Remove the stator cover. A good impression of the cleanliness of
the system can be made by inspection of the common exhaust
chamber and the inside of the stator cover. If there is evidence of
dust, liquid, or other residues then it may be advisable to inspect
the RMS further as detailed in the following sections. It is often
possible to determine which inlet ports are the source of any
contamination, particularly in the case of liquid residues. Check
the gas conditioning for any suspect streams.
Seal Inspection and Replacement
The rotary seals are difficult to remove, and could be damaged in
the process. It is advised that spares are available before starting
work.
Sample Arm Seal
Follow the instructions in
“Filter Replacement”
above to the
point where the sample arm is removed. Inspect the sealing edge
of the sample arm seal and if there is serious scoring or other
damage the seal should be replaced. Note that the design of the
inlet means that it is tolerant of leakage at this point and any
leakage would be in the cross port sense. There is no danger of an
ambient leak.