Brochure

Possible cause What to examine How to find the error
Increased leak loss.
Compare QH curves and power
curves. If the curve is a horizontal
displacement which decreases
when the head (the pressure
difference above the gap) falls,
there could be an increased leak l
oss. Leak loss is described in section
5.3.7. Measure the sealing diameter
on the rotating and fixed part.
Compare the results with the
specifications on the drawing.
Examine the pump for other
types of leak loss.
Replace the impeller seal.
Close all unwanted circuits.
0-series
Pump with leakage
40
35
30
25
20
15
10
5
0
H [m]
0 5 10 15 20 25 30 35
Q [m
^3
/h]
0-series
Pump with leakage
2200
2000
1800
1600
1400
1200
1000
800
500
H [m]
0 5 10 15 20 25 30 35
Q [m
^3
/h]
121
Table 3 (continued)