Series RMI-B
close-coupled design
Page
15
9430-005-en
Revision 03
TM 10456
Edition 06/2022
6.3 Shutdown
♦
Close discharge valve down to the position "mini-
mum flow rate"
♦
Switch motor off.
♦
Close discharge valve completely.
Only close the suction line if the pump is to be evacu-
ated 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, ob-
serve the local regulations.
If the pump has been operated with a charge-
able 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
Section 3.1
.
6.4 Restarting
When the pump is restarted, it must be ensured that all
the relative steps as described in
Section 6.1
are
repeated, depending on the progress of the shutdown
operation.
6.5 Improper operations and their
consequences (examples)
Inadmissible modes of 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) may
result from these inadmissible modes of operation;
their occurrence can only be prevented by adhering to
the intended use.
Operation with magnetic drive stopped:
♦
If no heat is dissipated, damage to the impeller and
drive magnet assembly may occur.
Pump is started up without medium :
♦
The plain bearings 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 closed too much :
♦
Pump may be destroyed due to overheating.
♦
Axial thrust too great.
Discharge valve opened 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.
Overrun of the admissible gas content:
♦
The flow may stop.
♦
Switch pump and vent off for renewed convey-
ance.
♦
Make sure that the gas content is not exceeded,
as described in the intended use.
