Richter V&A RMI Series, Инструкция по установке и эксплуатации

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Series RMI
Page 12
9430-050-en Revision 00
TM 9886 Edition 03/2018
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.
5.4.2 Nozzle loads
The pump can be subjected to nozzle loads acc. to
DIN EN ISO 5199. See also TIS 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 gra-
dient towards the pump. Otherwise, gas bubbles may
form which considerably reduce the suction line cross
section. Eccentric transition elements must be in-
stalled 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 gradi-
ent 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.
Fig. 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