MTR(E), MTC, MTA - Grundfos

Selection and sizing
Selection of pumps
Selection of pumps should be based on
• the duty point of the pump
• sizing data such as pressure loss as a result of
height differences, friction loss in the pipework,
pump efficiency etc.
• minimum inlet pressure - NPSHR.
1. Duty point of the pump
From a duty point it is possible to select a pump on the
basis of the curve charts shown in the chapter of
"Performance curves/Technical data starting on
page 38.
p
[kPa]
2000
1600
1200
800
400
0
H
[m]
240
220
200
180
160
140
120
100
80
60
40
20
0
P2
[kW]
2.4
1.6
0.8
0.0
NPSH
[m]
8
6
4
2
0
-8
-7
-6
-5
-4
-3
-2
-1
-2-1
-1-1
0 100 200 300 400 500 600 700 800 Q [l/min]
0 10 20 30 40 Q [m³/h]
Fig. 27 Example of a curve chart
MTRE 32
MTR,
Hz 60
ISO 9906 Annex A
1/1 P2
Eta
P2 2/3
0 100 200 300 400 500 600 700 800 Q [l/min]
NPSH
0 100 200 300 400 500 600 700 800 Q [l/min]
Eta
[%]
80
60
40
20
0
TM01 4305 3700
MTR(E), MTC, MTA
2. Sizing data
When sizing a pump the following must be taken into
account:
• Required flow rate and pressure at the point of use.
• Pressure loss as a result of height differences
(Hgeo ).
• Friction loss in the pipework (Hf ).
It may be necessary to account for pressure loss in
connection with long pipes, bends or valves, etc.
• Best efficiency at the estimated duty point.
• NPSHR value.
For calculation of the NPSHR value, see "Minimum
inlet pressure - NPSHR" on page 36.
33