5. Installation
20
PNEG-2174
Sampler - Model GRA
Compressed Air Consumption
A complete sampling cycle requires that the sample cutter drive cylinder either extend or retract. To
determine the compressed air requirements to operate the sampler, multiply the consumption per cycle
(refer to chart) by the number of cycles per minute. The number calculated is the SCFM (Standard Cubic
Feet per Minute) of air required. A typical cycle takes between 1-2 seconds, depending on the sampler
size and speed control valve settings.
The pneumatic system on the sampler, consisting of the filter/regulator, directional control valve and air
cylinder was pre-plumbed and tested at the factory. The regulator is factory set at 80 PSI.
The regulator cannot increase downstream outlet pressure above the upstream inlet pressure. If the
pressure from the regulator is not sufficient to operate the cylinder, some means must be found to increase
the inlet pressure to the regulator. Recommended air supply pressure is 80-100 PSI.
Model/Size
Air Consumption per Sample Cycle @ 80 PSI
GRA-6 and 10
0.36 SCF
GRA-14 and 18
0.59 SCF
GRA-22, 26 and 30
0.91 SCF
