4 Degas the Sample
V
ACUUM
P
REPARATION
The vacuum preparation method should be used only with materials which are not likely to
fluidize.
Some fine-powdered samples such as controlled pore glass, fluid-cracking catalysts,
and carbon may be difficult to prepare by vacuum preparation. Such materials tend to
fluidize and float up the sample tube toward the vacuum source. Micromeritics
recommends that such samples be first prepared by flowing gas preparation and, if
necessary, then be subjected to vacuum preparation.
If sample has been accidentally sucked into the instrument, see
Vacuum Fittings on page 5 - 13
.
1. Turn all VAC/GAS control knobs to the OFF position. Ensure that the vacuum pump is
powered ON and that gas is being supplied to the degasser.
2. Attach a vacuum fitting to each piece of flexible tubing at a degas station to be used for
sample preparation.
1/2 in. or 12 mm O-ring and
ferrule (for 1/2 in. or 12 mm
sample tubes)
3/8 in. or 9 mm O-ring and
ferrule (for 3/8 in. or 9 mm
sample tubes)
3. Power on the VacPrep.
4. Set the temperature controller using the temperature set point.
5. Remove the stopper from the sample tube and attach the sample tube to the vacuum fitting.
a. Loosen the knurled retaining nut.
b. Insert the sample tube fully into the fitting. There will be a slight resistance as the tube
passes through the O-ring.
c. Turn the knurled retaining nut until it is finger-tight.
Tighten the fitting retaining nut only finger-tight. Over-tightening may break the
sample tube.
4 - 2
VacPrep Operator Manual
061-42802-01 (Rev B) — Apr 2021
