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
WILDEN PUMP & ENGINEERING, LLC 10 PX220/PX230 Performance
EMS CURVE SETTING 4 PERFORMANCE CURVE
This is an example showing how to determine the inlet air
pressure and the EMS setting for your Pro-Flo X™ pump to
optimize the pump for a specific application. For this exam-
ple we will be using an application requirement of 18.9 lpm
(5 gpm) flow rate against 2.8 bar (40 psig) discharge pressure.
This example will illustrate how to calculate the air consump-
tion that could be expected at this operational point.
Step 1
: Establish inlet air pressure. Higher air pres-
sures will typically allow the pump to run
more efficiently, however, available plant air
pressure can vary greatly. If an operating
pressure of 6.9 bar (100 psig) is chosen when
plant air frequently dips to 6.2 bar (90 psig)
pump performance will vary. Choose an oper-
ating pressure that is within your compressed
air system's capabilities. For this example we
will choose 4.1 bar (60 psig).
Step 2 : Determine performance point at setting 4. For
this example an inlet air pressure of 4.1 bar
(60 psig) inlet air pressure has been chosen.
Locate the curve that represents the perfor-
mance of the pump with 4.1 bar (60 psig) inlet
air pressure. Mark the point where this curve
crosses the horizontal line representing 2.8
bar (40 psig) discharge pressure. After locat-
ing this point on the flow curve, draw a verti-
cal line downward until reaching the bottom
scale on the chart and identify the flow rate.
In our example it is 38.6 lpm (10.2 gpm). This
is the setting 4 flow rate. Observe the loca-
tion of the performance point relative to air
consumption curves and approximate air
consumption value. In our example setting
4 air consumption is 24 Nm
3
/h (14 scfm).
(See figure 4.)
Step 3
: Determine flow X Factor. Divide the required
flow rate 18.9 lpm (5 gpm) by the setting 4 flow
rate 38.6 lpm (10.2 gpm) to determine the flow
X Factor for the application.
Step 4
: Determine EMS setting from the flow
X Factor. Plot the point representing the flow
X Factor (0.49) and the application discharge
pressure 2.8 bar (40 psig) on the EMS curve.
This is done by following the horizontal 2.8
bar (40 psig) discharge pressure line until it
crosses the vertical 0.49 X Factor line. Typical-
ly, this point lies between two flow EMS set-
ting curves (in this case, the point lies between
the flow curves for EMS setting 1 and 2). Ob-
serve the location of the point relative to the
two curves it lies between and approximate
the EMS setting (Figure 5). For more precise
results you can mathematically interpolate be-
tween the two curves to determine the opti-
mal EMS setting.
5 gpm / 10.2 gpm = 0.49 (flow X Factor)
DETERMINE EMS SETTING
For this example the EMS setting is 1.8.
Figure 4
Example data point =
10.2
gpm flow multiplier
Figure 5
EMS Flow
Settings 1 & 2
Example 2.1
0.49