© 2000 Baker Hughes, a GE company – All rights reserved.
PV 411A Instruction Manual-English | 7
3.
Using the scissor-action handles, generate the approximate vacuum; then turn the
volume adjuster clockwise (in) to decrease the vacuum or turn the volume adjuster
counterclockwise (out) to increase the vacuum.
For low vacuum use the volume adjuster only.
3.2 Generating Pneumatic Pressure and Vacuum
(Figure A1)
Connect the pump as detailed in “Connecting the Pump” on page 5.
Note:
Compressing a gas generates heat. Gas heated or cooled in an enclosed volume
causes a pressure change. It is important to allow enough time for the heated gas to cool
and the pressure to stabilize.
The pumping required to generate a pressure depends on the volume of the system.
Therefore, keep the system volume to a minimum.
3.2.1 Pressure
1.
Turn the selector valve (7) fully clockwise (in) position.
2.
Operate the scissor-action handles (5) to generate the approximate pressure, allow
time for thermal stabilization.
3.
If necessary, use the volume adjuster (3) to adjust the required pressure.
4.
After attaining the required pressure operate the scissor-action handles (5) to
generate a higher pressure. Alternatively, vent the pressure to atmosphere by slowly
turning (counterclockwise) the selector valve (7) to the center position.
5.
After completion, depressurize the pump and disconnect from the pipes and
equipment.
3.2.2 Vacuum
1.
Turn the selector valve (7) fully counterclockwise (out) position.
2.
Operate the scissor-action handles (5) to generate the approximate vacuum, allow
time for thermal stabilization.
3.
If necessary, use the volume adjuster (3) to adjust the required vacuum.
4.
After attaining the required vacuum operate the scissor-action handles (5) to
generate a higher vacuum. Alternatively, vent atmosphere into the vacuum by slowly
turning (counterclockwise) the selector valve (7) to the center position.
5.
After completion, depressurize the pump and disconnect from the pipes and
equipment.
