English (GB)
11
3.5 Inlet pipe guidelines
3.5.1 Common guidelines
Avoid air pockets or turbulence in the inlet pipe
Never use reducers in a horizontal inlet pipe as shown in fig.
. Instead, use an eccentric reducer as
illustrated in fig.
3.5.2 Flooded systems
Closed systems and open systems where the liquid level is above the pump inlet.
3.5.3 Suction lift systems
Closed systems and open systems where the liquid level is below the pump inlet.
Install the inlet pipe sloping upwards towards the inlet port. Any high point in the pipe will be filled with air and
thus prevent proper operation of the pump. When reducing the pipe to the inlet port diameter, use an eccentric
reducer with the eccentric side down to avoid air pockets.
Correct
Wrong
TM
04
00
9
3
49
07
TM
04
00
9
2
49
07
Fig. 9
Correctly mounted reducer
Fig. 10
Reducers resulting in air pockets and
turbulence
Eccentric reducer
Turbulent flow
Air pocket
Concentric reducer
Correct
TM
04
01
4
8
49
07
Fig. 11
Correctly mounted inlet pipe
Eccentric reducer
Pipe sloping down
towards pump
Correct
Wrong
TM0
4
0
09
8 4
9
0
7
TM0
4
0
09
7 4
9
0
7
Fig. 12
Correctly mounted inlet pipe
Fig. 13
Inlet pipe resulting in air pockets
Eccentric reducer
Pipe sloping
up towards
pump
Eccentric reducer
Air pocket
Pipe sloping
down towards
pump
