Richter RMA-B Series (ASME) - Manual (Page 15)

Series RMA-B close-coupled design Page 15
9475-055-en Revision 14
TM 8256 Edition 06/2011
6.3 Shutdown
Close discharge valve down to the position
"minimum flow rate"
Switch motor off.
Close discharge valve completely.
Only close the suction line if the pump is to be
evacuated or dismantled.
For all work on the machine, make sure that
the motor cannot be inadvertently switched
on.
If the pump is to be evacuated or flushed,
observe the local regulations.
If the pump has been operated with a
chargeable liquid, it must be filled with inert
gas (e.g. nitrogen) to prevent an explosive
atmosphere.
It is recommended to wait one hour before the pump
is dismantled from the plant to permit static peak
charges to be eliminated.
If the pump is returned to the manufacturer's, clean
the pump very thoroughly.
See also Chapter 3.1.
6.4 Restarting
When the pump is restarted, it must be ensured that
all the relative steps as described in Chapter 6.1 are
repeated, depending on the progress of the shutdown
operation.
6.5 Improper operations and their
consequences (examples)
Improper operation, even for brief periods,
may result in serious damage to the unit.
In connection with explosion protection,
potential sources of ignition (overheating, electrostatic
and induced charges, mechanical and electric sparks)
can result from these inadmissible modes of
operation; their occurrence can only be prevented by
adhering to the intended use.
Pump is started up without medium :
If no heat is dissipated, damage to the inner and
drive magnet assemblies may occur.
Pump is started up without medium :
The plain bearing in the pump may be destroyed.
Other pump components may be destroyed due
to overheating.
Suction line not opened or not opened fully :
Pump is cavitating – material damage to pump
and plain bearings
Pump does not attain the required delivery head
or flow rate.
Pump may be destroyed due to overheating.
Discharge valve opened too much :
Pump may be destroyed due to overheating.
Axial thrust too great.
Discharge valve closed too much :
Pump can cavitate. Particularly severe with an
empty discharge line.
Risk of pressure surge.
Possible damage to the plain bearings.
Magnetic drive may stop.
Motor may be overloaded.
Suction valve and discharge valve closed :
Destruction due to rapid overheating and sharp
rise in pressure.
Control of the pump with the suction valve :
Cavitation – the volume may only be regulated on
the discharge side. Cavitation – the volume may
only be regulated on the discharge side.
Overrun of the admissible gas content:
The flow may stop.
Switch pump and vent off for renewed
conveyance.
Make sure that the gas content is not exceeded,
as described in the intended use.