SMC Networks PA3000 Series, Manual, Page: 4 / 29

Performance Curve: Automatically Operated Type
Required specifications example:
Find the pilot air pressure and pilot air consumption for a discharge rate of 6
l
/min and a discharge pressure of 0.25 MPa. <The transfer
fluid is fresh water (viscosity 1 mPa·s, specific gravity 1.0).>
∗
If the total lifting height is required instead of the discharge pressure, a discharge pressure of 0.1 MPa corresponds to a total lift of 10 m.
Selection procedures:
1. First mark the intersection point for a discharge rate of 6
l
/min and a discharge pressure of 0.25 MPa.
2. Find the pilot air pressure for the marked point. In this case, the point is between the discharge curves (solid lines) for SUP = 0.2 MPa and
SUP = 0.5 MPa, and based on the proportional relationship to these lines, the pilot air pressure for this point is approximately 0.38 MPa.
3. Next find the air consumption rate. Since the marked point is below the curve for 50
l
/min (ANR), the maximum rate will be about 50
l
/min (ANR).
Required specifications example:
Find the pilot air pressure and pilot air consumption for a dis-
charge rate of 2.7
l /min, and a viscosity of 100 mPa·s.
Selection procedures:
1. First find the ratio of the discharge rate for fresh water when
viscosity is 100 mPa·s from the graph below. It is determined
to be 45%.
2. Next, in the required specification example, the viscosity is 100
mPa·s and the discharge rate is 2.7 l /min. Since this is equivalent
to 45% of the discharge rate for fresh water, 2.7 l /min
÷
0.45 = 6
l /min, indicating that a discharge rate of 6 l /min is required for
fresh water.
3. Finally, find the pilot air pressure and pilot air consumption based
on selection from the flow characteristic graphs.
Selection from Flow Characteristic Graph ( PA3
첸첸
0)
Selection from Viscosity Characteristic Graph
Viscosity Characteristics
(Flow rate correction for viscous fluids)
Caution
1. These flow characteristics are for fresh water (viscosity 1 mPa·s, specific gravity 1.0).
2. The discharge rate differs greatly depending on properties (viscosity, specific gravity) of the fluid being
transferred and operating conditions (lifting range, transfer distance), etc.
3. Use 0.75 kW per 100
l
/min of air consumption as a guide for the relationship of the air consumption to the
compressor.
Caution
Viscosities up to 1000 mPa·s can be used.
Dynamic viscosity
ν
= Viscosity
µ
/Density
ρ
.
ν
=
ν
(10
–3
m
2
/s) =
µ
(mPa·s)/
ρ
(kg/m
3
)
PA3
첸첸
0
Flow Characteristics
PA5
첸첸
0
Flow Characteristics
0.6
0.5
0.4
0.3
0.2
0.1
0
Discharge rate ( l /min)
Discharge pressure (MPa)
SUP = 0.7 MPa
SUP = 0.5 MPa
SUP = 0.2 MPa
Air consumption 100
l
/min
(ANR)
Air consumption 50
l
/min (ANR)
SUP = 0.7 MPa
SUP = 0.5 MPa
SUP = 0.2 MPa
Air consumption 200
l
/min
(ANR)
Air consumption 100
l
/min (ANR)
10 20
0.6
0.5
0.4
0.3
0.2
0.1
0
Discharge rate ( l /min)
Discharge pressure (MPa)
10 30 40 50 20 60
100
50
0
1 10 100 1000
Viscosity (mPa·s)
Ratio of discharge rate against fresh water (%)
µ
ρ
672
Series
PA