Dover PSG Wilden PX220, Engineering, Operation & Maintenance

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H O W T O U S E T H I S E M S C U R V E
PX220/PX230 Performance 11 WILDEN PUMP & ENGINEERING, LLC
EMS CURVE SETTING 4 PERFORMANCE CURVE
Example 2.2
Determine air consumption at a specific
EMS setting.
Step 1 : Determine air X Factor. In order to determine
the air X Factor, identify the two air EMS set-
ting curves closest to the EMS setting estab-
lished in example 2.1 (in this case, the point
lies between the air curves for EMS setting
1 and 2). The point representing your EMS
setting (1.8) must be approximated and plot-
ted on the EMS curve along the horizontal
line representing your discharge pressure (in
this case, 40 psig). This air point is different
than the flow point plotted in example 2.1. Af-
ter estimating (or interpolating) this point on
the curve, draw a vertical line downward un-
til reaching the bottom scale on the chart and
identify the air X Factor (Figure 7).
Step 2
: Determine air consumption. Multiply your
setting 4 air consumption (14 scfm) value by
the air X Factor obtained above (0.40) to deter-
mine your actual air consumption.
In summary, for an application requiring 18.9 lpm
(5 gpm) against 2.8 bar (40 psig) discharge pressure,
the pump inlet air pressure should be set to 4.1 bar
(60 psig) and the EMS dial should be set to 1.8. The
pump would then consume 9.5 Nm
3
/h (5.6 scfm) of
compressed air.
Figure 6
0.40
air multiplier
Example data point =
Figure 7
10.2
gpm
Example data point =
For this example the air X Factor is 0.40.
14 scfm x 0.40 = 5.6 SCFM
EMS Air
Settings 1 & 2