5.4 Piping
Before the pump is installed, both, the suction and supply lines as well as the discharge line are to be
cleaned.
Dirt or damage to the sealing surfaces is best avoided if the flange covers remain on the flanges until just
before installation.
Use flange gaskets suitable for the medium.
The screw tightening torques in
2.3 Tightening torques on page 12
are to be observed for tightening the
flange screws.
5.4.1 Nominal size
The operating design point of a centrifugal pump lies at the intersection of the pump curve and the pipe
curve. The pump curve is provided by the pump manufacturer. The pipe curve is determined using dia-
grams or PC programs.
Figure 6: Pump curve diagram
1.
Pump curve
2.
Operating design point
3.
Pipe curve
Under no circumstances can the nominal size of the piping be derived from the connected nominal size
of the pump.
The pipe nominal size can also be determined using the flow rate as a rough guide.
The velocity in the suction line should not exceed 2.0 m/s and 5.0 m/s in the discharge line.
When determining the suction line nominal size, the NPSH value (net positive suction head) must also
be observed. The NPSHR value required for the pump is specified in the data sheet.
CAUTION:
The NPSHR available in the plant should be at least 0.5 m higher than the NPSHR required
for the pump. Otherwise, this will lead to a drop in the delivery head, cavitation or even failure
of the pump.
5.4 Piping
20
Model ICM/ICMP Magnetic Drive Chemical Process Pump with Grease Bearing Lubrication Installation, Operation, and
Maintenance Manual
Содержание Goulds Pumps ICM
Страница 2: ......
