26 | 180R9288_AQ109686503100en-001301
© Danfoss | 2023.12
Operation guide
Installation, Operation and Maintenance Manual for PAHT 20-90 pumps
5. Flow
The flow (Q
eff
) at various pressure (p
max
) can be
calculated with the following equation:
Q
eff
= Q
(th)
– [(Q
(th)
– Q (p
max
)) x (p / p
max
)]
The theoretical flow can be calculated with the
following equation:
V x n
Q
(th)
=
1000
At zero pressure the true flow equals the
theoretical flow Q
(th)
.
Q
(th)
:
Theoretical flow (l/min / gpm)
Q (p
max
): Flows at max. pressure (l/min and
gpm), see 4.1-4.4
p
max
:
Max pressure (barg / psig)
p:
Pressure (barg / psig)
V:
Displacement (cm
3
/ rev.)
n:
Motor speed (rpm)
5.1
PAHT 2-6.3 typical flow curves at max pressure
20
18
16
14
12
10
8
6
4
2
0
rpm
PAHT 2.0
PAHT 3.2
PAHT 4.0
PAHT 6.3
l/min
1
0
0
0
1
2
5
0
1
5
0
0
1
7
5
0
2
0
0
0
2
5
0
0
2
2
5
0
2
7
5
0
3
0
0
0
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
gpm
0
1
0
0
0
1
2
5
0
1
5
0
0
1
7
5
0
2
0
0
0
2
5
0
0
2
2
5
0
2
7
5
0
3
0
0
0
rpm
PAHT 6.3
PAHT 4.0
PAHT 3.2
PAHT 2.0
