Ametek Dycor Dymaxion Mass Spectrometer, User Manual

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Sampling System
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5-5
Replacing/Installing the Capillary
You will need a 3-meter length of 50 micron I.D. capillary (consult
factory before varying length) that will be long enough to span the
distance between the point at which the capillary attaches to the
capillary inlet valve and the point at which the free end connects to
the sample source.
1. Insert the capillary (4) through the nut (3) as shown in Figure 5-4.
2. Insert the capillary through the narrow end of the ferrule (2).
3. Insert the capillary into the capillary inlet valve fitting (1) to a depth of
about .75 inches (2 cm).
4. Tighten the nut (3) using a 1/4” wrench so that the nut compresses the
ferrule against the capillary to make an air-tight seal.
Use the mass spectrometer to ensure that there are no existing leaks in the
manifold when the capillary inlet valve is closed as follows:
• Using the Dycor System 2000 software, ensure that there is no air leak
by verifying that the 28 peak is more than 5X the height of the 32 peak,
and that there is no peak at 14.
Once you have verified that there are no air leaks with the capillary valve
closed, check the leak tightness of the capillary seal as follows:
• Insert the free end of the capillary (4) into a soft rubber material to plug
the end.
• Open the capillary inlet valve.
• Using the Dycor System 2000 software, ensure that there is no air leak
by verifying that the 28 peak is more than 5X the height of the 32 peak,
and that there is no peak at 14.
• If you do not see these conditions, tighten the nut until these conditions
exist.
Once you have verified that the connection has an air-tight seal, you can con-
nect the free end of the capillary tube to the sample source.
5. Use the M1442 Capillary Connector (5) in Figure 5-5 to attach the free
end of the capillary tube to the sample source.
NOTE

1
2
3
4
Figure 5-4.
Capillary inlet system.
1. Capillary Inlet Valve
2. Graphitized Vespel Ferrule
3. Capillary Nut
4. Fused Silica Capillary