Set Source Gas Pressures - Agilent Technologies 8860 Installation And First Startup

1 Installing the GC

Set source gas pressures

The pressure set at a tank regulator depends on these factors:
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Table 6
Table 6
Gas
Carrier
Air for FID, FPD
Hydrogen
Makeup gas
TCD Reference
Air for valve actuators
38
The inlet pressure needed to achieve the highest column flow rate required by your
method.
The pressure/flow relationship depends on the column or device involved. The best way
to address this is to begin at a moderate pressure level and adjust upward as needed.
A pressure difference of about 170 kPa (25 psi) across flow controlling devices enables
them to work properly.
The pressure limit of the weakest part of the supply system.
Swagelok fittings and copper tubing are more than adequate for the highest pressures
used in gas chromatography.
We recommend a maximum continuous operating pressure of 1170 kPa (170 psi) to
avoid excessive wear and leaks.
Traps are often the weakest part of the system. They should be labeled, either on the trap
itself or in accompanying literature, with a maximum operating pressure. Source
pressure must not exceed the lowest maximum operating pressure in the supply
system.
suggests starting values of source pressure.
Suggested starting pressures
Use
Packed column
Capillary columns
Detectors
Detectors
Detectors
TCD
Valves
Source pressure
410 kPa (60 psi)
550 kPa (80 psi)
550 kPa (80 psi)
410 kPa (60 psi)
410 kPa (60 psi)
410 kPa (60 psi)
345 kPa (50 psi)
Installation and First Startup