Richter RMI Series - Manual (Page 12)

Series RMI
Page 12
9470-050-en Revision 00
TM 7978 Edition 08/2010
The NPSHR available in the plant
should be at least 1,64 ft (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.
5.4.2 Nozzle loads
The pump can be subjected to nozzle loads in
accordance with DIN EN ISO 5199. See also TIS-No.
0541-02-0006.
Changes in the length of the piping caused by
temperature are to be allowed for by appropriate
measures, e.g. the installation of expansion joints.
5.4.3 Suction line
The suction lines must always be laid on a rising
gradient towards the pump. Otherwise, gas bubbles
may form which considerably reduce the suction line
cross section. Eccentric transition elements must be
installed between different pipe diameters.
Valves which disrupt the course of flow should not be
installed directly upstream of the pump.
Fig. 3
5.4.4 Supply lines
Supply lines should vent towards the reservoir and
are therefore to be laid with a constant downward
gradient towards the pump.
Should the piping internals upstream of the pump be
horizontal, a low point can, of course, be located
upstream of these internals.
From here the pipe is then laid with an upward
gradient to the pump so that the gas bubbles which
form here can escape through the pump.
Valves which disrupt the course of flow should not be
installed directly upstream of the pump.
5.4.5 Discharge line
Do not arrange the shut-off valve directly above the
pump but initially provide a transition section.
The discharge nozzle velocity of the medium can – if
necessary – be reduced.
5.4.6 Venting and evacuating
Venting can take place into the discharge line or
upstream of the discharge valve.
A venting line can also be used as a bypass, drain or
flushing line.
The pump housing is fitted with a drain connection
as a standard feature. Optionally, the drain bore can
be drilled.
See Fig. 4.
Bild 4
5.5 Pipe fittings
The following pipe fittings are available from Richter
on request:
Shut-off valves
Check valves
Sight glasses
Priming vessels
Strainers
Pressure gauges
Fig. 5