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 (
N
et
P
ositive
S
uction
H
ead) must be
observed. The
NPSHR
-value required for the pump is specified in the data sheet.
The
NPSHA
-value available in the plant should be at least 0.5 m higher than the
NPSHR
-value required for the pump. Otherwise, this will lead to a drop in the delivery
head, cavitation or even failure of the pump.
2.5.5.2
Nozzle loads
The pump can be subjected to nozzle loads in accordance with ISO 5199 [MNKA, RMA, RSA:
ANSI/HI 9.6.2]. See also TIS 0541-02-006. Changes in the length of the piping caused by tempera-
ture are to be allowed for by appropriate measures, e.g. the installation of expansion joints.
2.5.5.3
Suction line
The suction lines must always be laid on a rising gradient towards the pump. Otherwise, gas bub-
bles may form which considerably reduce the suction line cross section. Eccentric transition ele-
ments must be installed between different pipe diameters. Valves which disrupt the course of flow
should not be installed directly upstream of the pump.
A
B
Fig. 6: Suction line
A Suction line
B Suction nozzle of pump
Safety and installation instructions for Richter pumps
Richter Pumpen /
pumps
Installation > Piping
20
Summary of Contents for MNK
Page 2: ...Richter Pumpen pumps 2...
