TA Instruments TMA 2940 CE, Operator'S Manual, Page: 82 / 178

Running Experiments
TA I
NSTRUMENTS
TMA 2940 CE 3–18
Using a Purge Gas
You can control the sample atmosphere during
TMA experiments by connecting a purge gas to
the system. You can purge the system using
inert gases or reactive gases such as air and
oxygen. The following gases can be used:
• Helium (recommended)
• Nitrogen
• Oxygen
• Dry, filtered air (to keep moisture, dirt, oil,
and debris out of the system).
If an inert atmosphere is needed, nitrogen gas
should be used. Close the furnace, and purge the
system with nitrogen for 10 minutes. Then
switch to helium gas for the experiment, if
desired. To ensure an inert environment for your
sample, a purge rate of 100 mL/min is suggested.
Enter the purge gas and flow rate information
using instrument control function; see the
software online documentation for details. The
sample purge connection is located on the right
side of the back of the TMA. See Chapter 2 for
installation details.
Suggestions
The following guidelines are offered for purging
the system:
• Pass the purge gas through a dryer
whenever you are working at subambient
temperatures, in order to remove any
moisture in the gas itself.