Performance Curve: Air Operated Type
Required specification example: Find the pilot air pressure and pilot
air consumption for a discharge rate of 6
l
/min. <The transfer fluid is
fresh water (viscosity 1 mPa·s, specific gravity 1.0).>
Note 1) If the total lifting height is required instead of the discharge pressure, a dis-
charge 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 dis-
charge pressure of 0.1 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 = 0.3
MPa, and based on the proportional relationship to these lines, the pilot air
pressure for this point is approximately 0.25 MPa.
Required specification example: Find the pilot air pressure and pilot air
consumption for a discharge 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 100m Pa·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
첸
13)
Selection from Viscosity Characteristic Graph
Caution
PA3
첸
13
Flow Characteristics
PA3
첸
13
Air Consumption
PA5
첸
13
Air Consumption
PA5
첸
13
Flow Characteristics
0
Find the air consumption for operation with a 4 Hz switching cycle and
pilot air pressure of 0.3 MPa from the air consumption graph.
Selection procedures:
1. Look up from the 4 Hz switching cycle to find the intersection with SUP = 0.3 MPa.
2. From the point just found, draw a line to the Y-axis to find the air
consumption. The result is approximately 50
l
/min (ANR).
Calculating Air Consumption (PA3
첸
13)
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 (density, lifting range, transfer distance).
SUP = 0.5 MP
a
SUP = 0.3 MP
a
SUP = 0.2 MP
a
2
3
4
5
6
7
20
40
60
80
100
120
140
160
1
0
Cycle (Hz)
Air consumption (
l
/min [ANR])
Cycle (Hz)
Air consumption (
l
/min [ANR])
Viscosity Characteristics
(Flow rate correction for viscous fluids)
100
50
0
1
10
100
1000
Viscosity (mPa·s)
Ratio of discharge r
ate against fresh w
ater (%)
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
)
µ
ρ
0.5
0.4
0.3
0.2
0.1
0
Discharge pressure (MP
a)
2
4
6
8
10
12
SUP = 0.4 MPa
SUP = 0.2 MPa
SUP = 0.3 MPa
Discharge rate (
l
/min)
SUP = 0.5 MPa
Cycle 7 Hz
Cycle 5 Hz
Cycle 3 Hz
5
10
15
20
25
Discharge rate (
l
/min)
0.1
0.2
0.3
0.4
0.5
Discharge pressure (MP
a)
SUP = 0.2 MPa
SUP = 0.3 MPa
SUP = 0.5 MPa
SUP = 0.4 MPa
Cycle 5 Hz
Cycle 3 Hz
Cycle 1 Hz
0
50
100
150
200
250
300
1
3
2
5
4
7
6
SUP = 0.5 MP
a
SUP = 0.3 MPa
SUP = 0.4 MP
a
SUP = 0.2 MPa
673
Series
PA
Process Pump
Automatically Operated Type
PA
PAP
PAX
PB
PAF
PA
첸
PB
Summary of Contents for PA3000 Series
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